Historic, archived document
Do not assume content reflects current scientific knowledge, policies, or practices.
* a ae
*
$
YHE PLANT DISEASE REPORTER,
BI | BELTSVILLE, MARYLAND
Issued By
The Office of Mycology and Disease Survey
Supplement 47
Diseases of Fruit and Nut Crops
In the United States in 1925
June 15, 1926
BUREAU OF PLANT INDUSTRY
UNITED STATES DEPARTMENT OF AGRICULTURE
“f y steer at! :
| wit My
t
; . 4 .
Eee s g ‘2
[ dpa ly , * rc? , beer 2.4 a Sw - ‘ eee - x tue 2 * %
* ‘ J ee » r _ r a { 5] Aw i | ae m i i % 3 65 ‘ am eV Mae at a ee ra) ea ht i Ch J sf “ in ‘ee a
Me’, i
: { ae FAUT LUSDS FAO LHEMTANIAG SATATE
ta nN ay Neen
| de feat } Me el ee ei ; i ry Py a ih: hy ue.
rane i
167
DISEASES OF FRUIT AND NUT CROPS IN Ti
EB UNITED ‘STATES IN 1925
Prepared by
F. J. Schneiderhan, Collaborator, Plant Disease Survey and Assistant Pathologist, Virginia Agricultural Experiment Station.
SECTION ON CITRUS AND SUB-TROPICAL FRUITS
Prepared by
H. R- Fulton, Pathologist, Office of Fruit Disease Investigations, Bureau of Plant Industry.
Plant Disease Reporter Supplement 47
CON Pferduuetran vr. 4h. SCAT LA BLA 168 Noteworthy observations .......... 168 suggestions to collaborators ..... 170 Weather of 1925 ...-.eeeees eevee 17 Temefature tes sei lee. ve. gees Me 173 Precipitation <fsi.ntt. 39. 88: - 76 Fruit diseases of 1925 ....--.e-e. 150 Diseases of pome fruits ....... 180 Rapes 2Ste lls VT sé. Ow dy Five. 180 ag oav ed ivecestberst 130 Bigeen es. et. SVECE BORG Pe 194 Seat Pust ews ese se 199 Blackrot ...... SUG SS 2G ‘ 20. Besecr FER SiG. 232 Git: »» 207 BYagee .Pet.. .tistegee.ed 209 Blister canker .....see.. e212 Prusy Spov fwd 1642 0G ga «8 213 Beyueer® PEt! 466.86 ae et re Jonathan Spot «..sseeees .2a%) DROWNESLE sccdiccewsaencs 215 Sooty blotch and flyspeck 219 Powdery Mildew ..-e.eeeee ra MBG@Erots Jie wal da» sbis o's. « 220 Frost injury -«.... exsses Cel Hail injury «cccesecceeseee 222i Other GiSCaSeS «reece enes 222 General referenges ...... Be Pear Jb4. 2424204 ne se PEe ba 22 QUINCE we ee cere ee des eeneeeee 259 Diseases of stone fruits .. . 236 PEMOE. «cave Wene Rain ws s seQSbuY 236
mat
Lil
June 15, 1926
{TS
_BEOWNEOL | «oe og.2 95 «mes sree « 246 demteurl «ts dees caeee mms 2 50 CAD ne ote are Oye atete aie p imon's - 2Al Pacterial spot ...-.... »» 242 Blight «ee. nals Heme @ = ahs 2A5 VelRews: aves onis a9 ap sald - 2A5 Tittle peach a sas se shenies 247 Spray Anjury «-seccaseces 2A Winter and frost injury . 24 ther diseases «eseress . 248 General references ...... 2A9 Plum and. prune sscewrcescns er 49\0 Quest y veers ae- Ges Saws ods Peele , 1255 Hor ices | amd ae ogee agate tbls §, 259 Diseases of small fruits ...... 260 GLADE (see se wee de ew ewer es wen » 260 Lrawberry, -Besese ae vememsns 266 RAS PDOLLy secesecsessesevens 268 Blackberry «eseusscvesesdes - 275 Dewberry eeseesceece st Bedemes 277 TOSEM DEFY ecasceciweccsssus 278 Gurtanh os'sedesweues Ves Cabs 278 GOOSEDEVLY sere cece cece eeeee 279 Cranberry cescvecsesesees eu wo eee Blueberry essewesccvsscoacde 201 Me ARGree .me+9 8 Ckeeann* ames * 6 281 Diseases of sub-tropical fruits 282 Giteuri+caereecnd tanends anes 202 Din we go etabantanebens eens un 289 Date Palm «-eewsececees eeeee 290 Pineapple sesecrersseceeeces LOL
168
OLIV Gi as sep mace ae seen ee, COL . Pomegranate sseeseeeeseeseee 294 AV oC ad. meets wee mteeian al Diseases of nuts. da sevebvase +. 294 9 MANZO ssavestesvssevssesees 292 PECAN cevevecsccecesvseeesee LY PAPAYA wessceceressseeneses O92 English walnut cecccssesees sey GUAVE “diet eeecn cess beceee ks Boe Japanese walnut eessereeees ef Banana “fio. Ae. 4 Py ee. ode ie 295 PbS «2+ » apes(a mays mpretgane se <4 Pers immon"? e7- rvs 2 PG Ge ote 295 Almond; is. see teedewhett<eaces a BreadfruLt seine s kab eam 22 29d Coconut esecscevrecscsccevens 2g
INTRODUCTION
The reader of this summary will probably be impressed by the fact that the year 1925 was very unique in so far as it demonstrated, to an unusual ex- tent, the correlation of weather factors and disease occurrence on the fruit crops of the United States. It is suggested at this point that the reader first glance over the abstracts of the monthly conditions of temperature and precipitation and the departures from normal given on pages 174 to 179 in or- der to get a better -interpretation of the comparatively slight fungous.losses on fruits reported for 1925. It is a well-known fact that weather is prob— ably the most impertant factor in the occurrence, development, and spread of plant diseases in-any particular year. In view of the fact that the country-— wide status of the weather in 1925 was in many respects the most extraordinary of the past 50 years, it will be interesting to. note how this condition is re- flected in the comparatively slight losses suffered from fungous discascs of fruits. : ie .
The predominance of data on apple discases which is again apparent as in previous years is due, very likely, to the widespread distribution of the host, but-is out of proportion to the economic importance of this fruit com-
pared with the other fruits such as citrus, grapes, peaches, strawberries, ctces@
It was considered to be a worth-while departure from the procedure in previous summaries on: fruit discases to include at the very beginning of the 1925 summary’a bricf digest presenting what appears to the writer to be some
of the noteworthy and interesting contrititions for the year. This digest will ©
enable the reader to sclect those contritmtions and give them his detailed at- tention if he desires.
DIGEST OF NOTEWORTHY OBSERVATIONS. CONTAINED. IN THIS SUMMARY
The unusually small damage caused by fungous: diseases in 1925 was prob- ably the main factor in the production of a larger commercial apple crop than in 1924, in‘spite of the fact that the total. applic. production in: the United States was approximately seven-and-a-half million bushels. less than in'192d4. Country-wide weather conditions in 1925 were most unfavorable for the devel- opment and spread of fungous discascs of fruits.
a
169
Ascospore = jcothen ahudicg of Venturia inaequalis were given particu- lar emphasis in 1925. Data from Wisconsin, Minnesota, New York, Pennsylvania, New Jersey, West Virginia, Virginia, and Tennessee indicate a rad tae close correlation between dates of heaviest ascospore ejection and subsequent ins fection by this fungus. In the Northern States the heaviest spore ejections occurred previous to and during the prepink and pink stage of the blossoms. In the, Southern and East Central States the period of maximum ejection oc- curred somewhat later, just before and during pink and calyx closing periods. The result of this was to make the delayed dormant and prepink sprays rela- tively more important in the North than farther South. Unusually late scab infection caused most of the. losses from this disease in New York and Minne- sota in 1925.
Blotch control cpercmiameie with various fungicides Mave oer ikl ne re- sults in New Jersey, Ohio, Illinois, Tennessee, and Virginia. The relative control value of each blotch spray has been correlated with blotch spore exu- dation from cankered twigs in Virginia. The etiology and control of blotch 224 been treated in a very comprehensive manner by Guba (Illinois Sta. Bul. 25 witads Studies of cedar rust spore discharges and the correlation of percen- tage and intensity of rust infection on York Imperial apple leaves with dis- tance from uncut cedar tree areas were made in Virginia. Notable results in cedar rust control due to the cutting out of the intermediate host, the red cedar, were also reported from that state.
Injury of fruit by blackrot was directly correlated with codling moth injury in Virginia and Indiana. In Missouri blackrot followed hail injury, while in Minnesota it was reported following fireblight.
A new apple rot which looks like blackrot but which is caused by Botryosphaeria instead of Physalospora has been described by Shear, Fenner, and others.
Apple bitter rot spore oxudation studies in relation to rainfall were conducted at Winchester, Virginia. The first instance ever reported in the Hast of the overwintering of this fungus in twigs.and fruit infection from this source was observed at Winchester. Twig infection had. previously been reported in South Carolina. |
Bacillg%s amylovorus, causing blight on apples, pears, and quinces is one of the few diseases reported to be of greater prevalence than normally in the United States in 1925. It was reported on cherry from Michigan and Kansas. An. outstanding contribution treating of the behavior of Bacillus _ amylovorus was made by Nixon. Migration of the organism in the form of zoogloea through intercellular spaces and the formation of cysts within the central vacuoles and hibernation in this form were determined in this study.
Notable results in research on crowngall were recorded in 1925. Toxic relations between black walnuts and apples were reported by Sehneiderhan of Virginia
losses due to frost injury on apples, pears, peaches, cherries, and plums were very cxtensive in most of the North Central and East Central States in 1925. Frost injury was the limiting factor in many statos. The largest hail insurance adjustment ($53,000) ever ‘paid for injury in one apple orchard in the United States was reported from Mt. Jackson, Virginia.
A new apple canker and fruit rot (Gloeosporium perennans s) in Wath teton and Oregon was described by Zeller and Childs. A new storage disease resembl- ing soft scald of apples was reported from Oregone
170
‘Beisor dust apnited to ‘peaches two or three weeks béfere picking in rainy weather considerably reduced brownrot in:transit. The practicability of peach dusting in Georgia and cranberry aoe in New Jersey by using aire
planes is also mentioned. ‘“:: Pawe- years of investigation ‘by H. W. wh bee cient? on the overwintering habits of Bacterium pruni under Illinois corditions have shown that the com- ‘mon’source of initial infection is not the cankered twigs alone but also in- fected leaves. Anderson's work on the control of bacterial spot (Bacterium pruni) with sodium silico-fluoride also is notable. The preliminary results indicate the possibility of using this material as a fungicide to coritrol the disease. The reports on the non-occurrence of peach yellows in Illinois and | Indiana and on the local outbreak of it in Michigan are noteworthy. The role of Aphis rubiphila in the transmission of raspberry leafcurl has been deter- mined by Smith. The possibility of false blossom of cultivated cranberries — being caused by an infectious agent is indicated by the investigations car- ried on.by Stevens this year. Spraying experiments in pecan scab control cars . ried on by Demaree indicate that bordeaux mixture is the most effective fungi- cide, while Neal, of. Mi Sea Seeppay reports: ‘distinct advantages in’ using bordeau: oil: emulsion. , |
SOME SUGGESTIONS TO COLLABORATORS
Better Cooperation on the Part of Gusioamere eek Needed
The writer being a collaborator may be pardoned for offering some sug— gestions to his colleagues on this subject. There is great diversity in the © Quality and quantity of the data supplied. Not all the collaborators are contributing satisfactory data regarding the major crops in their state, even in cases in which certain’diseases are among the limiting factors in the pro-—
duction of these crops. The compilers of the annual disease summaries have — been greatly impressed by the small amount of information available regarding certain crops and from different states. An examination of the annual fruit and nut disease summarics of the past three years shows that every compiler
has made constructive suggestions for the improvement of the annual survey,
and there has been some improvement, particularly in the data submitted from — the Far West and from certain states west of the Mississippi. It is, however, plainly apparent to any one who makes a critical inspection of the data in- — cluded in the present summary that there is room for much additional improve- ment and that the annual compilations for the various crops cannot be of maxi-= mum usefulness unless more complete and accurate information is supplied.
In reviewing the attitude of former compilers the following quotations were taken from the last three annual fruit disease summaries:
Adams, J. F. Supplement 25: 268. 1922. "In summarizing the data by
collaborators in 1922 certain, conditions have been stated and suggestions made which are pertinent to disease problems in general. Greater cooperation
along certain lines indicated in the summary would assist materially in ex- plaining and coordinating disease conditions and contribute to the working out of more efficient control measures. The Plant Disease Survey affords a "clearing house! for brief reports on the results of investigations that might seriously-be delayed through other means of publication."
| ¢ | & Goa & , 171
| . . Orton, C. R. Supplement 35: 36. 1924. “Practically all of the re- ports in 1923 came from the eastern half of the United States, while only a
few scattered reports came from the rest of the country. From the great fruit~ producing state of California a very meager amount of information was avail- able. The Plant Disease Survey can never hope to carry out its purpose in
Q fully creditable way until full cooperation from collaborators in each
state is securcd."
Giddings, N. Je Supplement 439: 2. 1924. "During the next few years there is going to be a tremendous increase in the use of the records of the Plant Discase Survey Office and every one of the collaborators who does his best to turn in accurate and valuable data will be amply rcpaid in more ways than one.- Of course it is understood the plant-disease problems are of more importance in some states than others and that the facilities and funds are inadequate for mach plant-disease survey work in most of the states. That phase of the probicm is one which we must keep in mind, but in the meantime we can all do our best with the facilities that are available."
it is obvious that the plant-disease summaries cannot include all the details of pathological research and discase conditions in every state every year, but the most outstanding events can and ought ta be set forth clearly in a publication of this kind so that a plant pathologist in any state or in. foreign parts can by reading the summary ascertain such facts as are most im- portant in the disease status of any particular state.
There is little doubt thet the annual summaries of di‘sensea off, fruits; cereals, vegetables, and ornamentals are the most comprehensive effort in that direction made by any organization in the United States. If these summaries are not what they should be the fault lies with us. It indicates that we, the collaborators, are not properly informed of plant-disease conditions in our ‘own states or else we lack the time or the inclination to furnish the disease data. In either case we show a lack of appreciation of the increasing value. of these annual summaries and furthermore we are not availing ourselves of an opportunity to become better known as Bay topappologpe ts.
A New Annuel Report Form
Examination of the survey cards Filled out by coblaburaters during the past five years shows that less than 50 per cent of the data requested is ‘actually entered. This is the fault of cither the card or the collaborators. Upon the assumption that the former is the chicf causc, considerable thought. has “been given to the preparation of a new report blank, and previous com- pilers of the summaries have been requested to contribute their ideas .toward its formation. The result is a new survey card, which it is hoped will be. found considerably better than the one uscd hitherto. The varying termin- ology possible in former cards has been largely climinated by a simple check- ing of definite terms printcd on the new card. There are other features: which will obviously make it easier for the collaborator to submit his data. The
w form of survey card will be found following this discussion. It repre- <9 the effort of the Plant Disease Survey to get more definite data, to facilitate the making out of reports by the collaborators and te eliminate rrr features of the old cards as were deemed impracticable. As is noted on-
~~ cnet ere oor Waal Se
ee UntiiAncd panei? Tan ‘ cre Ieee : ee e = ele BIZeBp ey TUT FOP SSOTUN SUOTZSONN
-
EEE SBOE CN esauy TTe gonsue 04 ydulej48 you oq :Oy0N
-oyo ‘suoTPeATESqO Tensnun ‘sounsBelu Torzzuoo ‘yOm mou f94BUTYS® SSOT JO STseq ‘:syreuier Teasouey
——$—— eS eo Pepsns Lica “ \ ee ee ee eg eo eg ig OT eoEne i : Seca eae ee, aaa cee ee ore -anereamcanmee~auneerttir din ititls iet E a s R queystTsou i | I SS Oe. he Sees tpon Aion 4
LV ee ee ouNUUT soTpeTseA |
SSeOSTP OF (19949)
** *oTQusoaesuny ounyeroduey, UTeTOxH| ** ++ *oTQeuoART
zeok stuy
eSBesTp OF (090 ) SUOT}ETON TOUyeO/h
"OTA eIcCAejuy » BIN STON
uTBeTdxy) ss *eTQeioaRys | ! =
—
4s0y jf eeeeeeseeenraty suo fue jo | Uy UOTPOOFUT % uNWUTXeW|(AT*Q MOTO e3e4¢9 (fy.un09) (UM07 ) uTeTdx | 90ei4 yeu 9999487 cere eee ceorereceeses see OORT YT 'FGsscePe ap £2 SSOT. Tew] ‘oT *O 2AOqe see ee OTH (19040) (fep) ( 47-0 ) ,“ “(aPenD) seunsty 2sf ) sas fT am umes vag ft ° * Wres 1 8 eho + a ee gin gig ()pe184 729g ( )TROoT ( \Terouen “ssor0 ‘qtsueay ‘e8es0rs DqeTE
2 ‘eperg uT ssolT %| Oy SSOT ~- Kanlut ieok sTuq esBesTp fo JIeok STyy 943849 UT
Inutxeu jo pofiog joouvnrvedde papiooea ysoT[iey | woTynqTazstp oTydeasoon
sees equsTTs (70°U)) ‘*ssoT yon (79949) ***SSeT Yoru (799uU0) week oFB10AaB Uep e******SseT [teed OBer0OAe Jeee****s*sSsoT] aweoOk 4SeT **ATTETOLOUMOD UMOUZ YOU (79949 )- **-aqRBTOPOUl/UT OSBOSTP STUIs ****** owes jpyyTm poreduioo|+++*+***oures;yqtTm pouedmoo|++*s*ssuTqyueTd Teuotssoo00 \soueyoduy
|s+eseeppete ut uotzonpod %
gO DOUv TIOGUT opeveorre oro DOUST BASU eeoeeoeevrs CO 70OU! DOUN TB ADT dg Fe ee ae eS ne ee Oe dor9 Lessee efaoal *"o70W Yon : ***or0W Yon mo ON ee SS Ss See scrap ope ?e* TBO) “Amc es eee es ee ee ee ee ee ee de ee ee ee ee ee ee eee CC « (©F84S ) suTqutad PES PPO HOS PRO RS OO Se eae ae eee a eee aD fDi eee te alae dnd delet Etat (iy ~ Lalo ated yw, 2"
17
JO} posn oq OF Soede
er er ee ah
5 ae age, Cate F \ 1'74
‘
the forms, it ts-nat expected that all the information for which space is pro- vided wil] or can be supplied. Reports should be made only on matters regard- ing which reasonably definite and accurate information is available -~ in other words quality is mech more importent than quantity.
. -
Sugsestions for Im#dving Collaborators! Renorts
(1) More definite records in all states of dates of the first and maxi- mam appearance of diseases, dates of spray applications, dates of maximum in- jury to crops, and more careful judgment in making estimates of losses by dis- eases and other injuries to crops.
(2) A careful examination of annual field, laboratory, and other De- partmental reports for the purpose of selecting and submitting to the Plant Disease Survey the most important results obtained during the current year's work. ay (4) Every collaborator should send in the disease card of every crop, regardless of whether the disease occurs or whether the erep is grown in that particular state or not. Notation on the card whether the crop or the disease occurs would be a great help in nreparing the summaries at headguarters.
(4) Sending in of survey cards before the cliose of the year. This, wai greatly expedite the difficult task of compiling the data for the annual sum maries.
fie WE eee RR OF i ee
In many respects the weather conditions of 1925 were the most unique of the past 50 years. It was unusually hot and dry and the combination over most of the United States resulted in a smaller loss from fruit Gissases than in 1924 or in the average year. There were, Of course, 1 where dry, warm weather did not prevail. It is a difficult task to correla Weather With discase occurrence over so Jarge a gecgrapnical area as the United States. Specific correlations are possible only in limited areas of individual states, therefore, any statement made in this suypicment in regard to country-wide correlation of weather and fungous disease occurrence mst
necessarily be construed as a general average to which local exceptions will
OCcCUre
Bas It is unusual to have the month of April show above-normal temperatures
_invevery state in the Union. The average tomperature for the twelve months
Was above-normal in every state in 1925, which is another unique record. An examPsgtion of the data in table 35 shows thet of the months from April to September inclusive, the important growing months in the largest part of the United States, only May was subnormal in temperature. Extreme temperature
174
variations occurred in June when 124° was recorded in California and below freez-— ing temperatures in Montana and the Oregon mountain section. The only month which was considerably below normal in temperature was October, during which the temperatures in the central and northern states east of the Rocky Mountains were the lowest on record for that month during the past 50 years.
The following statements of the temperature conditions by months were abstracted from The Monthly Weather Review (Vol. 54. 1925).
January
This month was free from pronounced and widespread cold waves. The greater part of the month was marked by persistent regional contrasts of temp- erature conditions, some states or portions of states having lasting cold weather while others were experiencing very mild weather.
February
The outstanding feature of the month was the mild temperature experienced in practically all parts of the country. There was an absence of cold waves. The condition resulted probably from the greaibarometric depressions centering over the Gulf of Alaska.
March
March 1925, like February, was characterized by abéve-normal temperature in all parts of the United States except the extreme southern tip of Florida. It was the second month of above-normal temperatures in all parts of the country, a rare occurrence.
April
Like the months immediately preceding, April 1925 was comparatively Warm in practically all parts of the country, especially cast of the Mississippi and south of the Ohio. Thus, the temperature was above-normal for the three consecutive months.
May
In the eastern districts an outburst of summer temperatures was exper-— ienced on the 23d and 2Ath. This was suddenly brought to a close by a wave of cool weather that swept southward on the 25-26th. On the whole, the month was was warm in the West and cool in the East, the Rocky Mountains being the divid- ing line.
June
An unusual June hot spell persisted in central and eastern districts dur- ing the first ten days of the month... The average temperature for the month was above-normal, a characteristic of 1925 thus far, except during May. The maxi- mum temperature observed was 124° in California while below freczing temperatures were recorded in the northern mountains.
175
July
The first two weeks of July were hot over the greater part of the coun- try. During the third week, the temperatures continued high from the Rockies Westward. The last decade of the month was gratifyingly cooler. In the Carolinas, Georgia, and certain Northern Plateau regions the monthly means of temperature were among the highest 6n record.
August
This month like its immediate predecessor was warm and dry- The cool- est periods were during the first part of the month in portions of the central valleys, but mainly during the last decade over the remaining portions of the country. Readings below freezing were reported in all northern border states. In the mountains of Oregon a temperature of 14° was reached.
September
The single outstanding feature of this month was the sharply contrasted distribution of temperature in various sections of the country. September 1925 set a record for heat unsurpassed in the authentic history of the sec- tion east of the Mississippi am south of the Ohio drainage systems and will probably stand unsurpassed for as long a time in the future. The weather was moderately cool in districts west of the Rockies and below freezing tempera- tures were recorded in the northern tier of states.
October
This month is the first in 1925 having a temperature considerably below normal. No previous October in the past 50 years ar.more has had such low temperatures over nearly all central and northern districts from the Rocky Mountains eastward.
November
Important temperature changes were rapid and frequent but the monthly averages were mainly not far from normal. Average temperatures were above-— normal on the Pacific Coast, along the entire northern border, and over New England. A moderately cool area covered the southeastern states and other
districts east of the Mississippi except along the northern border, New England, /and Florida. The lowest temperature reported was 21° below zero in the moun- tains of Colorado.
a a
December
coli i tle! eld kil
West of the Rocky Mountains the weather was moderately warm throughout /the month, in fact, portions of the far Northwest had the highest December
averages Imowh. From the Great Plains eastward and generally over the south- ee the temperatures were below normal except in portions of the North
: Atlantic States and extreme southern Florida.
. In table 45 the data relative to the departures from normal of both _ temperature and precipitation for all states during April to September inclus- ive are given.
Op BAS
EP Enemies
176
‘ PRECIPITATION
The year 1925 will probably be long remembered as one of the driest in. the history of the United States Weather Bureau records. From January to October, the average precipitation throughout the country was far below nor- mal. In the southern Appalachian section, the drought was of unprecedented severity and duration, causing the oldest springs to dry up and resulting in geueral inconvenience and hardship. Nothing comparable to it is on record for the entire history of that section. It has been observed that even in years of sub-normal rainfall throughout the country certain spring or summer months will show above-normal precipitation, but in 1925 every month from January to October was sub-normal.
The following discussion treats of rainfall conditions by months dur-— ing 1925. This informtion was abstracted from The Monthly Weather Review
(Vol. 53- 1925).
January
Viewed as a whole, the month was one of scanty precipitation, except in south central, southeastern,east central and far northwestern states. Severe floods followed a considerable excess of rain in southeastern states. In California and Arizona the water shortage was serious.
February
This month was remarkably dry, particularly in the southern sections. From central Califormia northward, the precipitation was mainly above—normal. Serious drought conditions prevailed from central Texas and Oklahoma to the eastern coast. In the northern states the precipitation was less than ususl during this monthd,
March
A marked defieiency in precipitation existed over much of the country except New England, New York, and Montana. In certain sections of the cotton belt the rainfall was the least in 50 years. The drought in southern Cali- fornia was broken. In New Mexico a severe drought had existed for over a year.
April
Precipitation as a rule was mostly below normal except in Arkansas, Oklahoma, western and northern Texas, where the drought was relieved during the last decade of the month. The drought is becoming increasingly serious in Colorado and New Mexico.
May
A shortage of precipitation was rather general in central and eastern districts and curiously enough there were generous rains in California, suf~ ficiently heavy. to injure crops locally. All states had sub-normal rainfall except Florida, New Mexico, California, and Oregon.
177
June
This monthwwas warm and dry except in the Missouri and upper Mississ- ippi Valleys and New England where precipitation, was. greater than usual.
July
The monthly precipitation was far less than,normal throughout the coun- try except in New England and the east coast states as -far south as Maryland. Nevada had the heaviest precipitation on record while the Carolinas and Georgia had the lightest in 50. a ae The water''shortage in the southern Appalachian states was acute. ; : 3
August
This month, like its immediate predecessor, was very dry- In the South- east, the Soubwest and in ‘some north central states the drought of July was intensified with the result that a most serious ‘situation with regard to stock and even for domestic purposes eee in many localities.
september
September added ei bed to the long list of months ih 1925 deri cibat in precipitation, ,The. drought-in the southeastern ‘sections ofthe country ‘re- mained unbroken. -Favorable rains fell in Texas and northeastward to the Great lakes section. see
October
The plentiful precipitation over most districts was in sharp contrast to that of many of te months preceding and very generally relieved the severe drought in the. Southeast. Precipitation.was.far-in excess of the normal over the lower: ea aie Valley and Gulf States.
November
From the Rocky Mountains eastward the bulk of the precipitation occurred during the first half of the month. Above-normal: rainfall occurred in the southern Plains Lake area eastward to the Atlantic. BeJjow normal rainfall occurred from the upper Lakes westward ‘ine luding the Missouri Valley, the Plateau Section and the Pacific Coast States, except southern California. The ° November totals. in parts of Florida, agtably at Miami, were the Jargest on record on ee month. : oye
}
December | » 7 ¢
For’ the sountry as a whole.precipitation was ‘deficient in hearly mi the states, and even where in excess, the margins above-normal were small except in Florida and locally along the South Atlantic Coast. where. the excesses were mainly duc to-heavy rains attending the “tropical storm of the first and second. In the far West, precipitation was everywhere less than usual:in December, ex- _ cept along the immediate gost districts of pep nekep and in a few other small arease : “it 2
‘
ris ® OLf0r. S ey*or? Gr-t+s Gore- = GLtOe fF ecvqe i Ought Ege Seth tye re : “TET ee*e+ * O4°0- = ZQrO+? SO°O-? OQ*ae = T2*T~ + oe Pegede § 680s Altea eye - tele oe * pul Geos * ert © Goto+? goto TI°t> * Gest~' +: ory: Foote ¢ LTRs GreerteeeG- + cue OTYO pag0= © Vpre- = = Te"O+* Toto Voro= + Coto st? ofGe 2 GIOe * 690 BS Ethe teoky= = yele 8 oe ee cro: * Veter: <= Geeo7t Greor*.Ge"T= * 6o%o- t+: of d+ |} SQROF § SOF Sees ykye * Pace oe *£Y poe * GGhe- ee Te*t-? pGste* dete~ * Gras? G*oe = eO"tH ° a . Te atopes= § gtGy 2 S Sieg CG*T+ = Qo°O- + GQ°O-# QQ°T-? TO*T- * GE°T- t=? O'z+ + OTO ¢ Aeae t Fhe § geo 2 VGr ¢ ~ Sexe] 69°T+ = Q6°IT- * QBt0-! £910" Ga*tt 2 geeGeet? ahve F VSO ¢ VTE WG tee te + Gee oe Oy] ero = 2os2- = TG*O-'. ocBtstacy*T- * ge*y-43! G+ © Oto © Ofte gees ep T= § eee Se *SSTW figeo- * LisGe<rtecotort ogeess Giet- § Peteeot? age 2 Ste | OPT Mote ee 5 Our. oe “ely Of°V- = GOTOH = QT*OH! QFrO-? GO°T+ = Gert 22 9°S+ ¢ Teor *% StO+ § ZtOe § Q*T- 2 VOR ? ‘eld misc * Siege Pagesg=* Ghote? “6G Ts ¢ a 99 f2 gO, oF TG 8 Tae Ghent t- + ae e 13) WE'z- * ove Obte-? Tito? gpet- * 2bto~ tt Sele ot Sete ot Lote? Ogg 1 ives. 2 ONS Ss ae Goet~ © COse= et soT*C-? GOT Act i~ * Ve*tett oor & “C80 2 Togs HOD © iGte= © Gtaes © "Oo °N oer 9 grees (SCG? GL ere dear t~ + ecror at Cols 4, Toate” 2 LOreteetpe | Bey- * eee “BA CG*T- 3 vou= : ae 69°T=: o4,*T- : 11,°0- es AYE . T % G*eo- : O° V+ : 6°¢o- : )* 2+ > *pN-* Ted ered * Yetce Ss Gor Tet Gress spero- * egret? Gece FS EO= ¢ oe Teeeerepe tee t Gage @ sed t4,°0- . th*2- . QLte+s V9"0~: S6°0- : 22°T- “3 ar ‘ 6°07 . te ° TaiGe : g*e- : T*eh : “Poon ey e+ * Ges’ 3 TGpco+* 6G"Ont teto- + Geeoe Ff: 9°0+ ts EG + gre~seGaee Bpey= soe. as *k *h Go°O+ * gh*T- ¢§ GOroe! Thor! Cbro- * gorT--t: Tom ¢. TeO+ ¢ ot@ ot o's 2 Pee * 6*te eBay men
oe
oe ee ee ov es se ee
~ydeg
! am) OF O w
(SeyouT) uoTzeqyTdtoorg 8724S
Teusrou Wors sinzredaq
*(GZ6T *6G metasy soyqeey ATUQUOW] eangtnoTaSy fo ywouyzaedog So4eyg peqytuy Wows ueye} sounstZ) ; saequeydeg 04 [Ttudy - seqeqs hq T[TegutTes pue sanqeseduieq [Tewsou oy} wous eanqredog *Go oTqe,
179
/Z*O+? Legs 0G *0~:
G*O+?
9°0+? Oo *T+5 FQ°Or#
Gv°o-: TS*0+! L9*0+: CZ°Or? V6°t-?
NO rc WwW © e ° : OO May fo fall ie ° ° Oo & + <tcoO N\ ©
e
O
ob
O io) l
INIA ON eS Wo dst co MANA oe ee a Vi >». ss se MmMeOoeao ooacs
t+ + t+ + + SR, Re ine LO DC-N NY eS COQ) KACO 0 A NOOR avo SPN «ee e# @ ® So ' Sey He ee fn) aye) CO Gy Oe i futon eo Se es ae I er ee ae ee es ee ee ee oe ee ee ee Qn) r
NVLAO
e e
© (@)
be +
Oo N) r + NS) NO O +
Gece * 1o*O= 4 Got 40%0-* - feqme % genuny Tne : oun —ydoq : : : :
GO*O+#*
(SOYUOUT) UOTPeYTATOSA, ©
29° O+ cS *O+
LT°O~ V2*0- 90°0™ ov*o- CT 08
6L°O+ Ov"O=
Sie! O ig 2 "Olas Wate =
oT = 67°T~ va je ae ve>=
9G*2- Gis o- Vs Wind Qg*2~
: OT8T+ f2 [8G 8. yet) 8 yt 2 OMe § Olle 2S oe eS eee : GG®o+ 2t.e"oe & .2°T= 62 § S9°T+ ee SS eee UuOBdIQ
e aN) +
ae +
“USB + ouepl * AON Wegn *ZTdy
NY
r
© I
+
NV NY +
se hia
. «8
NY ) oo
a
ri XO e Sa + au {
-r +
< oT
°
ha tt +
2 e + ee
e dona +
!
Ree ons 4
Desi cae NV O +
eviny wo WN
4.
cO ro & +
*xoNl °N *OTOD “of “quo *e TO
Lo
oO» © I + +
ea
Nal <r Ss { O90n- + + ° + +
+
xh aot iy O +
e I e + s + . + ee
ro ee)
©
Te
sed
ae
ae O N ONMCO SO = Sie e e ode Pog + MAOH eO OHOMO e
J NANA eA + WN <FO ord 2 Ole
&
ON NNN wo LAS A + +
+
aN rr m4 + + « SO > +
se ee
e mc oO G:O + I
* Suey *IGON "med °S > s3eqd °N ‘IY
Ble + oe + +
ws
es + + e * ee
re $4
zr =i ahs
LO O e © + + + I ! + LO O*~O ++ +
LO r N
! + e fe +
! Fd
ee e
es
se
° ° Ol : BMOT
SO) N) > + + + +
OPN
CY O I + TE + ! a
: cO ° O+ os * C+ : : *uUUTIN [VSO + eae st Te 8 TT OG ei ee ee “STM
an a Oo + SPSMO10 WO RBMENM DO NYMEM On avo
NMOO + SA MMOD MOtmO OM SHA a BO). Cr Pe LOVIN) ELON No On st ems =
AN Shin LO Sa
Ook—Fexr WOxo ma t
G.O CN. ON. ~- Oh esc AON
+ 2
SS La RA ee
* ae Rey
a
Cay eat OnthaAicG a @ coy FG aia iae
8 UH ae SE oe S| +
+
2 LO ee
+
+ Oo co Min Cy erie Olt et
: *4yoTN
s
ee ae ee ‘ee
LOQqUa ~qdeg
ysneny
TTzay
s « r) o Saat, Eee ° » e
ee se ee
8445
ee ee _—_— fey °
sonnets SNCS
TeuAoU Wors sinjzredag eS ee
eee Ot VENOM See nore Lk SE aE Pia ES ee ee ee
180.
FRUIT DISEASES OF 1925
DISEASES OF POME FRUITS — APPIR .
The total apple production in the United States in 1925 was 164,616,000 bushels compared to 171,250,000 bushels in 1924. However, the comercial production in 1925.was: greater, amounting to 41,909,000 barrels compared with 28 , 063, 000 ee in 1924. The total estimated value of: the apple emop in 1925 is $207, 820,000.00 while that of 192% oe $08 3 000.00. In the erder of production the states .ranked as follows: Washington, New York, Idaho,’ Michigan, and Virginia. The state of ia ee peeeueee by far the largest crop of any of the states.
‘
- SCAB CAUSED BY VENTURIA INABQUALIS (CKE.) .ADERH.
Geographic distribution:
Compar atively efagiiet scab.was of minor importance” in the United States in 1925. As usual, it was co-existent with apple culture. :Of t States reporting, one, Tennessee, reported more scab than normal, while: = York, Groeotl, Cale arnia, and Tennessee reported more than.in 1924. From the information. at hand-it appears that scab was more prevalent'on the Pacific Coast and in New England than in other sections of, the country..
Relative prevalence
It is evident that the eee criterion for _estimating -a scab epiphy- totic in any particular year is to compare its prevalence with other years. The Plant Disease Survey has data on relative prevalence-of scab for. the eight-year period -1918- 1925, inclusive. The year 1925 represents one of. the low water marks for scab, during the past-eight yéars. ‘Table 36 shows the relative prevalence of scab in 1925 compared with 1924 and with the average year. Of the states, reporting, fourtcen-reported less scab than-norml, four reported normal, and one more than normal. Comparing scab prevalence in 1925 with: 192A, only five states, New York, New Hampshire, Oregon, | Tennessee, and Washington reported more scab, while fifteen, states Bee ee less, and five others, reported -the same’ as the year ‘previous.
J. F. Adams of Delaware reports, "Prevalence. mich less than last two years.. High-temperatures and smal] rainfall have-held disease in check. |
In Virginia, according to Fromme, "The crop for the state as a whole
is Quite free from. scab. and.there will be’ comparatively slight loss." From the ‘same state Schneiderhan reports, "Studies of scab infection cycles in 1924 and 1925 indicate a striking contrast. In 1924 there were four distinct cycles of infection, while in. 1925 there was only-.one- primary: cycle with practically no secondary infection." .
| 198. APPLE — Scab
From Ohio, Young reports, “Apple scab is of minor importance this year where any type of spraying or dusting was done."
In Minnesota, according to the Section of Plant Pathology, "During the rainy period early in September, considerable leaf infection developed in most of the apple regions. Up to this time there had been very little scab especially on the fruit which was almost entirely free."
From Washington, which produced the largest apple crop in the country. this year, the Department of Plant Pathology reports, "Apple scab has been very scarce in eastern Washington and imch less common and severe than usual in the western part of the state."
In Oregon, one of the few states reporting more scab than 192A, accord- ing to Barss, “Long continued cool, wet spring weather has resulted in an un- usual incidence of scab in susceptible varieties and in unsprayed and improp- erly protected orchards in western Oregon." In contrast to this statement we have that of Childs reporting from Hood River, Oregon, "Scab is not gener- ally prevalent in the Hood River Valley, but in the upper Valley near Parkdale some orchards showed from 15 to 20 per cent fruit infection this year."
In California, another state reporting more scad than last year, Milbrath says, "A large amount of late infection. Hardly an orchard in state without some scab."
From Manitoba, Canada, Bisby reports, "More scab than usual."
Table 36. Relative prevalence of apple scab in 1925 compared with 1924 and average vear.
: Prevaience compared -:: ; Prevalence compared State : with $2 State : with . : -: Average :3 : : Average New Hampshire : more =: # Iless :: Indiana ;: dess : Jegen Connecticut : same t same 2: Illinois : less : less New York — : more - oo :1 Micnigan : less : less New Jersey : less : oe :: Wisconsin ; less : less Delaware : less : —~-- 3; Minnesota : less : less Maryland > . less 2 -+-— 9: Towa less : less Virginia : less : less :: South Desleneee same : same West Virginia : less : less :: Kansas >: same :_ iless Tennessee : more -; more ° +1: New Mexico ; Same ¢ aaa North Carolina: less : less :: Idaho : os : less Alabama : same : sane :; Washington ; ---- : less Oklahoma : less ° ; less :: Oregon —_—_: more : ---- Arkansas : less : less :: Oalifornia : more : os Ohio : dess : —--- ie : $ Losses
Naturally the losses resulting from scab in the United States were considerably less than last year. In spite of the fact that a few states report greater prevalence, the actual reported loss in yield is less. New York, which reported greater prevalence this year than in 1924, had a loss of only 10 per cent compared to 20 per cent in 1924. In the United States as a whole, the total apple crop was smaller than in 1924 by approximately
182 APPLE ~ Scab
seven-and-a-half million bushels, while the commercial crop was approximately three-and-a-half million barrels larger. This is a significant fact, which may be explained partly at least, by a lighter toll taken by fungous diseases. _ The data in table 47 indicate& the losses from apple scab in all states reporting during the past eight years. The last line of this table, giving the losses for the United States, is probably the most significant and indi-. cates a yearly alternation of high and low scab losses. During the period re- corded, there have not been two successive years of high losses. The weather, particularly rainfall, from the prepink until the 5-week spray is probably the most important siggle factor in the determination of scab prevalence in any particular year, unless a typical late infection occurs, as reported in Minnesota and New York this year. However, late infections are eaeey as se- vere and injurious as the earlg type.
A digest of all the reports on scab for 1925 would seem to indicate that losses were minor in properly sprayed orchards. The discase was easily controllable because of weather conditions adverse to the fungus. The heaviest losses this year were due to late infection. |
Weather gn relation to scab in 1925
Weather conditions, as previously remarked, were unfavorable to scab development in 1925. In the Eastern Unitcd States the reports are very similar and mostly to the effect that conditions for initial infection were slightly unfavorable but that drought following the blooming period effectively reduced primary and sccondary infection. In Massachusetts the spring was dry, while July was wet. Delaware reports subnormal rainfall and above-normal temperature. Similar conditions prevailed in Virginia, North Carolina, Georgia, and all of the lower Appalachian Highland section. In Arkansas the weather was very dry. In the states of Ohio, Indiana, Illinois, Michigan, Minnesota, Iowa, Kansas, and South Dakota the carly srowing scason, particularly April and May, was very dry and warm thus preventing to a large extent the normal initial infec- tion.
In contrast to the above mentioned conditions, we have the Long-con- tinued, cool, wet, spring weather in Orcgon. In New York, according to D. D. Ward, in the New York College of Agriculture Weckly News Letter, June 22, (Onandaga County) -~ "Some apple scab injury on foliage is showing as a peut of the rainy period just at the close of blossoming. Very little of the Calyx application was applied prior to the rain."
Anderson (Illinois) reports on July 1, as follows, "May 15 was the date when scab was first observed at Urbana. Practicaily no scab in southern end of state on account of cxtremely dry spring. lightest infection ever known."
Bennett (Michigan) under date of September 1 says, "The dry weather has almost completely held scab in check. There is very little fruit infection on unsprayed trecs. Considcrable late infection is now showing up."
According to Vaughan (Wisconsin), "Harly infection much less than usual. This is associated with the extended drought of May. Extremely contrasting conditions prevailed in 1924 and 1925."
Schneiderhan reporting from Virginia says, "The total rainfall for April, May, and June, 1925, was 7.59 inches. Last year it was 18.16 inches. Approximatcly 70 per cent of the total annual ascospore discharge in 1925 oc- curred in April, too carly for normal infection. A light initial scab infec- tion resulted in practically no sccondary infection because of the extremely dry weather in May, June, and July. The year 1925 was most unfavorable for fungous development."
AV)
APPLE - Scab
Table 37. The percentage of reduction in yield duc to apple scab in the United States for the period 1918 to 1925 inclusive.
State : Percentage reduction in vicld due to apple scab
Meee l ¢. J922 » . 1044 2. Dee wane) = Average
bw
NWO)? Nf F OLN ORIN OO}
° ° ° s WOO HM HPAQUTUIA~JW MUTI COB BO UI WDB OY OWN OVID OWN HM COW
IN °
° Ww
e J
i WO HUI
7)
i Ww ) MW Wut |
ae ee es ee se e¢ ee e mM I NWNNM EWE OO) jb rh NIN fe ODF UW OW ONONOTINOOT EON BH! OW OF
Mee _ + : 8. ae _ So. - p+ Bs sockets N. He t 5. 10. - 3 Ens ee S, trflks f os > Ae Vt. = ud OL Te Se A, fay any horee aes Mass. ee Be SES es = ee a one 5. - 2) Be Ra» Ee - dea ee - ee eee ee - - A os) Conn. ree See a eae Qvho0 oF N. Y. 5. eno). a Se ales - ees +. Sieg. wae 10. :10. Nadi edo Lis. Ob : 2: ets a Oaks Sy lites hes ote Pa. fh Giosay ae ee Pee 40. | t. Aw cst BBs oe 212. . Del. - elles ~seae “han Age a gm ; LO. ‘5a oi Ae Md. t BAL als sy eee Si ele ee aah Qe : Va. 2 SISA : a gee oS yas cay : 18. A. : Oe Ws Va. t POLARS ; ys Ss ie aa Sa oe = : 4e N.C. i Balls?) I ea a a aero ie Cae Sé-C 1. ks a7 Hh > = t apie i Lee = oy Ga. igi lear, Lees vo HS ee as 6. 1 Pla. - ey = oe < oe : ~) = Ohio - steer Gis HOM rit ss 10. 0.5 : Ind. 4 : 3e yO . . ae a. £51. : 6. Be SME , > os. press 0.5 ; : 8 a : 5 egowsdaels é : A A eu hee 5 N. De So ‘aa Ce - : 3 - das ~ ° oS. D. a we Oe > 15. —— : ° ~ AeGe = ) Je . Nebr. ee : 8. ie’ 2 Ba es a = 30 le ° Kans. t ary ie Re bw: Fs 16 1.5 0.5 , Ky. He ee = ths = a ay 40. 20. 10% Lise Tenne 5. - 10. : 2G t We 2. 1. 10 pa Ala. oe A. pe oes ieee 4. 2. _ Maree 2 Miss. ~ t Ls ae: ~ t t - : O. la. - ae — > oo ppt os - - = : + Texas oo _ 0 5 vu 2 - w 2 6) i Okla. fo) t Se) hem - Be - : Bul Ark. Ze Died 8. 2s ee 0.5) 0.5 t , & : | Mont % , o a ee = see Ue = = % fe y lbs Wyo. Pe ast tact nied ; - ecisnmois «3 Colo. t t fe oh pe e 7 e) 7 ide N. Mex. = = O ~ = = - - ae. : 26 s 2s Arize ~s O si sis pe ) ae és Utah - - a = - ~ ° = ne
s PO od
cr & ct
OMpPo Oo
184 -APPIE - Scab
Data _on ascospore emission
It has been generally recognized, particularly during the past six years as a result of special studies correlating ascospore emission with infection, that the time of first emission and the period of maximal emission of asco- - spores are probably two of the most important factors in the determination of an epiphytotic of scab in any particular year. Comparing such northern apple producing sections as Wisconsin, Michigan, and New York with the more south- ern ones of Delaware, Maryland, Virginia, and West Virginia we find a differ- ent-correlation between initial ascospore emissions and vegetative advance- - ment of the tree. It is apparent that ascospores begin to discharge in these northern states when the trees have advanced comparatively little from dor- mancy, while in.the other states mentioned, first ascospore emissions usu-- ally occur just previous to and during the pink and blooming period. The re- Sult in the North is that the delayed dormant or prepink sprays are of rela- tively greater importance for scab control than in the states farther South.
Wisconsin: According to Keitt and Wilson (13) conditions affecting the abundance of ascospores of Venturia inaequalis and the time of their maturity and discharge are of much potential import- ance in relation to the development and prevention of epidemics of apple scab. A marked relationship was observed between the time of leaf fall and ascospore maturity. Under conditions studied, ascospores matured much earlier in leaves which fell in the garly autumn than in those which remained on the tree until -aifum or early winter. Temperature and moisture were shown to be factors of cardinal importance in determining the rate of development of ascocarps.
The work of Frey and Keitt (i) shows periodicity of asco- spore discharge in 1917. The presence of an. adequate amount of water was the most important requisite for spore discharge. Wetting by dew did not cause discharge. Conidia of the scab fungus were found in the air only during rainy periods particu- larly when rains were accompanied by strong wind.
Delaware: Adams (1) showed that the prevalence of the disease was found to be associated with ascospore discharge de ending upon weather conditions. The heavier infection in Sussex County Was found to be correlated with earlier maturity and discharge of ascospores.
Virginia: Four years of investigation at Winchester have enabled us to determine the relative control values of the so-called scab. sprays. The pink anc petal-fall sprays are the most important and account for approximately 60 per cent of the total control value. The 10-day spray is valued at 10 per cent and all of the remaining sprays at 10 per cent. Control values of scab sprays are correlated with ascospore ejection. The pink and petal-fall sprays are most valuable -because approximately 60 per cent of all ascospore ejections are intercepted or nullified by these sprays. (Schneiderhan)
185
APPLE ~ Scab
As a result of a request for special ascospore ejection data it was pos-— sible to prepare the following tables. Similar data for several years, a much more comprehensive knowledge of the regional behavior of ascospore emission wouid result. It is suggested that these and additional states report such or similar data next year.
If the same states would contribute
New York: During May, 1924 the rainfall was 4.5 inches. In°2925 it
was 1.4 inches.
The raigiroad estimate for scab-free fruit for
‘eq was AS per cent; for 1925 it was 75 per cent. Most of our scab in 1925 came ieee following a late primary infection. (Massey) .
Table 38. The dates of ascospore discharge, rainfall causing them, and the dates of spray 2 ak Vili Wayne County, New York,
1925.
Date
ee
‘Rainfall.
A wt
-Date of
of —— Sennen spray application
hen 1 May May May~ LO May -16 May 24 June 1
ee
15 .30 15
. 05
225 225 225
ated dormant, April 24 Ist pre-blossom, May 8 end pre-blossom, May 16 Calyx, May 20
act rcover; june 9
me mes ee _— ~
° (SS eee i eee eee ee.
Table 39. Dates of ascospore discharges, the extent of discharge together with rainfall causing them, and dates of spray application, New. Brunswick, New Jersey, 1925.
Rainfall.
(inches)
1.06 0.03 0.03 a 0.04 0.19 0.10 0.46 0.05
: Spore discharge : Spray application
of —
ate ae Pink Medium : - Medium ° g = Heavy : - Light ae - Light : - Light : Petal-fall Light Vie ~ Light : Wes Medium ; tea
a : 7-day
~=<~ — — —_- <—- _—_ — — -_- —- —|-— hl - _—_ — om Se a _ —
186
———
Similar data for Moorestown show that the first spore
APPLE - Scab , : Rainfall Date (inches). 0: se Spore dT SChar eee _Sprey application _
May 22 - _ 17-day . May 2A 0.49 Medium - May 25 0.52 Light - May. 26 a = _ May 27 » hi ehh = May 29 0.29 Ret alte - May 40 0.49 Medium _ June 10 sae Light - June 1 Bit Medium ° - June 1 -14 - Medium . ~ June 18 £ Medium - June 2) t - = June 22 t - = June 24 0.04 ~ = June 25 0.07 ~ = June 2 t - = June 2 0.04 - ~ June 40 1.49 ~ -
discharge oc-
was 56 days; 1923, 9
First scab appearance May 10.
Most important spray - Pink. : Unusually short ascospore discharge period of 31 days. In 1922 it Scie 1924, 61 days. ua
94 days;
curred on April 25. First scab infection occurred at Vineland, May 15. (Martin) Table Aes Heo é3ection data, Winchester, Virginia, 1925. adalah “i a Date ina ——— eieotion _ Spray Same! April 10 OA Light : Delayed dormant, : March 26 April 14 50 Heavy : Pink, April 12-16 ApriloLy ~ 1G Light | --- April 24 - LO Heavy --- Apri 2h 98 Very heavy : ac April 26 «16 Light : Petal-fall,: April 27 April 28 A5 Heavy Vee = Apri bk -29 £38 Light -—-- April 40 sy Medium --- May 4 0 ‘Light --- May 5 00 “Light : 10-day, May 11 May 22 ~74 Light : --- May 29 “19 ~ None : 4-weeks, ‘May 29
137° APPLE: - Scab
Table 4] indicates the importance of ascospore ejections of May in Vir- ginia. A striking correlation exists between rainfall causing ascospore dis- charges in May and yearly infection.
Table A], A four-year summary showing correlation of ascospore. ejection with rainfall and scab infection on unsprayed Stayman fruits at Winchester, Virginia.
elocal. ©) Tota = Lora
: Scab Year +:_Number of ejections and rainfall : ejec- : rain : period :infection : (per cent)
ADELE: : : - tions :(inches):
me2 2 A(2. 50): az. 63) ) :3(4.0
feet Oe 1G 2. OO. 56 95.5 ies + i(2. 33) 2 ACL.) :5(1.94y25(5. 351s 15: YA: 9A a2 a924 : 5(1.70) -:.7(10. 9) ees e540 14 Cl alongs) ae 61.9 fey: 9C3.50) : ae AW). SOC lee) «(ae 3: 7.59 31 6.5
(Sehneiderhan
-in ee TO
yr:
*Rainfall (inches
Scab development in Wisconsin was not sufficient to give a satis factony test of the various fungicidal programs used.
Table 42, Dates of ascospore discharges correlated with rainfall and spray applications, Sturgeon Bay, Wisconsin, 1925.
Bates. of. «= Rainfall in : discharge: inches __: Spray application April 26 -: trace : Delayed dormant fori 29°. trace : --- May 4 Pepe B08 : Wis May pr ae ee ie -~-- May Fo ees we Pre-pink May 11 Hi: Q.O01 : --- May 14 : Oe one --- May vi ; trace : --- May 1 - 0.09 © : ==> May 17 : 0.49 : Pink May el : 0.5 : eS May “4 : °Q.0 - --- fay 2 : 0.14 : -~-- May 29 go" 0s08 - chlbesi as June 2 gti 0.08 skh Peeve". June A : Gezorkt : --- June 5 chy 5 0.02 : Bt Da June 12 : — 0.36 H --- June 1% ; 1.45 --; 1O-day June 14 : O17 : ~-- June 15 ; 0.61 : Sortie June 1 : O. O04 : --- June 2 0.00 : --- June 27 0.09 : ---
meme eee Ole lees i Se Se Se ES
APPLE ~ Scab |
~
Dates ef .: Ratieat? an =
discharge _: inches —_: Spray application June 29 : 0.01 - --- July 2 - : 0.27 : Sy. et July 4 ° 0.09 = -_- —- — July 4 : Gs0t . : —~—--= July 7 ss 0.14 : a SOS July 5 Fs 0.46 ~ a July a : 0.14 : = ee *. Largest number discharged this date The heaviest
Gischarges of the season took place batecce May 55 and May 30. (Keitt & Wilson)
ilaryland:- The following abstract was prepared from a paper b n and SE ae entitled "Factors in Scab Development" read. before the Maryland State Horticultural Society:
"Leaves containing perithecia of the apple scab fungus were placed in moist chambers: in a greenhouse and outside. Temperature records were kept in. both locations. In the greenhouse the minimum temperature was ag F., the maximum g0°, and the average was approximately 60°. The minimum tem eee outside was 13°, the maximum 77°, and the-aver- age Ay, - The first ascospore discharge in es greenhouse occurred 25 days after the leaves were placed in the moist chamber. Under outside conditions the first discharge oc-— curred 26 days after exposing the leaves. Under the con- ditions of this experiment, it would seem that comparatively high temperatures do not increase the rate of ascospore de-—- velooment and that they develop just as rapidly at an aver- age Eeenor of 40° as they do at an average temperature ef 60°.
West Virginia: . The data on ascospore discharge for Jefferson and- Berkeley Counties, West Virginia, are practically the same as for Winchester. <A letter from E. C. Sherwood, (West Virginia) to F. J. Schneiderhan, (Vi irginia), under date of January il, 1925, states, "You may know, however, that your data at Win- chester correspond exactly with my field notes. I remember cnecking ‘them with your records at the time I visited your laboratory. You have my authority, therefore, for using your own, (Winchester), notes as typical of our conditions in that section." (§ neste) |
Pennsylvania: The dates of first ascospore ejection’-in Pennsylvania in 1925 Were BS allows |
April 16-17 Bedford and Alleghany Counties Aprai.49 Philadelphia and Delaware Counties
APPLE - Scab April 21 Center County April 28 First heavy discharge in Center County April 40 Franklin and Venango County
You will note from these dates that conditions in Pennsylvania are far from uniform. The most important spray for scab control varies with the region of the state under consideration. [In some regions this was the delayed dormant and in others as late as the pink. (Thurston)
Tennessee: First ascospore discharge at Knoxville was on March 20. This was not general. On April 12 an abundant discharge occurred. The dates of spray application were: delayed dormant, March 10; pre-pink, March 16; pink, March 24; calyx, April 16; 10- ae April 26; five-week, latter part of May. Period of heavies? discharge was just prior to April 12. The most important scab spray was the pink spray. First scab appearance May 15. (Andes)
? Le
illinois: No data on period of heaviest ascospore ejection but probably no discharge at all to speak of. I collected leaves containing
perithecia here at Urbana early in April and found mee would
discharge spores when moistened, but we did not have sufficient
rains reeling the maturing of the ascospores cs we about
discharge. (Anderson)
Minnesota: Apple scab, ordinarily considered to be one of the most in- jurious diseases of apples in Minnesota, was of negligible 1 portance, even in unsprayed orchards, dw#ring the season of 1925 Primary infection spots, which usually appear on the leaves about the middle of May, were not reported until the middle of dune and then only a few were found. No scab was reported on the fruit at any time during the summer and very little appeared on the jeaves until late fall, at which time secondary infection spots became quite abundant. The slow start of apple scabd and its failure to spread until late fall was undoubtedly due to weather conditions. Usually, ripe perithecia are abundant shortly after the first of May and before the leaf buds are open- Ripe peri- thecia, in the past season, were very scarce up to the middle of Mey, probably because of the extremely dry weather during April and the early part of May. At no time were perithecia abundant. (Sect. Pl. Path.)
Thee re tae
The following information was reported by Peterson of the Section of Plant Pathology, University of Minnesota.
fable 44. The probable dates of ascospore discharges in Minnesota in relation to dates of spray applications in 1925.
: Rainfall : Probable spore Date (inches) discharges
Soray dates
Mey: 21-3: 205 : Probably first >: Dormant, April 27 : >: spore discharge :
150
APPLE - Scab
5 + Batnrats : Probable spore :
Date... sot (inéheske a23 discharges : Spray dates
May +5 : 225 : Probably period : Pink, May l May lo ; 225 : of heaviest dis-—- : May 19° ¢ 1.00 its charge : Calyx, May 20 June 1 + -05 : Probably some dis-: 10-day, May 41 Hane es 73 -O7 : Charge at these : : : dates : Sr Tae : : : : ‘ eee:
First primary infection noted June 20.
No 5-week sprays applied.
Results: No scab in sprayed plots or in checks.
Dates of first appearance of scab in 925
The variation in the dates of first appearance of scab within any pars, Considering an area as large as the United States with the disease occurring in every state, this variation is still greater. In 1925 the earliest appearance of scab was noted on April 17 in Delaware (Adams). The latest initial infection by scab was observed on
ticular state from year to year may be wide.
month late for Minnesota."
e 22 in New Hampshire (Butler). In Minnesota, as reported by the Section Plant Bem OLOE ys "In the Twin Cities region and southern part of the state, imary infections apparently took place about June 1 which is approximately
In view of the fact that scab infection through the season may occur in several distinct cycles, as reported in Virginia and recorded on page the 1924 Supplement, the importance of the date of initial appearance may not
De very great in any particular year. A more cribing an epiphytotic of scab is the date of largely upon the periodicity of rainfall, the and secondary infection. It is true that the
an important bearing on secondary and total yearly infection, but t+ first appearance of scab may not be;:.and ugualas 4s AOL 5 primary infection cycle. We need more data from the various states relati
important consideration
ew
in des-
maximal appearance which depends chief causative factor of p extent of primary infection has
bhe dat
to the Seasonal behavior of the scab fungus following .initial infection.
In New York, according to Bucholz, "There
rimary
e of
at the peak-of the
Ta VY
was very little infection
carly in the season. In fact it was not noticed very much before summer. With
rainy periods in July, scab began to be apparent
able percentage developed."
Dates and location of earlicst reported appearance. of: s
April 17 Seaford Delaware —. May 18 - Dutchess Co. May 10 Winchester Virginia | May 26 Orono
May 10 Berkeley Co. West Virginia May 28 Amherst
May 13 Milford Connecticut June 4 Burke Co. May 15. Vineland New Jersey - June’ ll- St. Paul
iay. t5 Vineennes Indiana June 22 Durham
Poet te & e a
fay 15 Urbana Illinois
Mew York Maine Massachu North Minnes ot New Hamp
and by September a consider-
setts arolina shire
A A
APPLE - Scab.
Oy.
Of the states repor4 bing dates of first appearance of scab, seven report later, five earlier, and one the same date as in 192A.
Varietal susceptibility
The data on varietal susceptibility contributed by a collaborators ‘th year were very fragmentary and, therefore, imoossible of compilation in a pire 2 resentative manner. The same criticism was made for the 1924: data. The ques~ tion of varietal susceptibility to scab is an important one. An examination of the data presented during the past eight years shows wide differences. For in- stance, in 1925 Jonathan was reported as very susceptible in New Mexico, whi le in Virginia this variety is known to be fairly resistant. Other examples could - be cited. . | ;
Control
From a country-wide standpoint.apple scab was easily controlled by proper Spraying in 1925. The data presented by the collaborators indicate that where- ever the pre-pink, pink, petal-fall, and 10-day spray were carefully applied, | scab control was very satisfactory, except where late-season infection occurred.
The following reports indicate in a brief manner the scab control status in 1925.
Maine: Unsprayed Ben Davis plot showed 11 per cent of leaves infected |
and 1 per cent of fruit. In nearby commercial Ben Davis orchards,~ sprayed four times, no-scab was seen- Nearby unsprayed Ben Davis © commercial orchards up to 45 per Gent scab on fruitse MoIntosh sprayed five times, trace a, No twig infection.on trees. Nearby commercial orchards. of Mcintosh up to 96 per cent scab; sprayed five: ciaiess up to 85 per oent scab. (Folsom)
7 Cele
Massachusetts: Continued wet weathor during July has greatly increased secondary infection especiaily where the usual spray schedule was not closely folicwed. (Osmun & Davis)
New York: The most important sprays hapsened to be the calyx in Ontarioa Genesee Counties, and pink along tne Lake region, that “is}° im Niagara, Orlcans, Monroe, and a Counties » (Massey)
Delaware: Mostly lcaf infection. ‘Only stight Pruit infection in un-~ sprayed orchards. (Adams } e
faryland: Showing up on aie unsprayed or > ‘poorly sprayed trees on leaves and fruits. ‘None noted on twigs as. was the case last. year. Not so bad as last year. . (Jehle)
Virginia: Scab was easily controlled in i925. Favorable weather eori— ditions for both ascospore ejection and infection occurred between the pink, petal-fail,..and 10- day ‘spray but the unpresedented.
- drought checked. the spread of the disease. There was practically. no secondary scab infection in northern Virginia in 1925. Peace & Schneiderhan)}
‘
APPLE -— Scab
Ohio: Of minér importance this year where any type of spraying or dust—. ing has been done. Weather conditions were not favorable for its development. (Young)
Indiana: Not serious except in unsprayed trees. (Gardner)
Tilinois: The season started with unusually high temperatures. This resulted in practically the entire absence of the pre-bloom in- fection of apple scab. I examined hundreds of trees for ‘scab Where in previous years one could not glance at a tree without Seeing scab spots, yet this season I was able to find but a very few infections. I am of the opinion that there has never been a season more unfavorable for apple scab. (Anderson)
Michigan: There is very little fruit infection on unsprayed trees. Considerable late leaf infection is now showing up. (Bennett)
Missouri: Heavy loss in unsprayed orchards in Dallas, Green, and Polk Countics. (lManeval)
Oregon; Five scab Ee with dry lime-sulfur or lime-sulfur followed by sulfur at cal 15 days, and 30 days applied. Bad weather conditions wally is a a for severity. In Lane County ac- cording to Fruit Inspector C..E. Stewart, loss was total on un- sprayed trees in many cases; and in some cases 15 to 45 per cent in sprayed orchards. (Barss)
According to a letter from Childs (Hood River), "In years past we have found that no particular spray is the most important one; this importance varying with seasonal conditions. On the average, - I believe the delayed dormant and pink applications are the most important considering the climatic conditions in this area."
For the control of apple scab in scabby orchards Butler (8) recommends a pre Veen pink, and calyx spray of Bordeaux mixture 2-2-50, and a 14-day W i time su ie bY ur 1-5 0 6
Recent literature
1. Adams, J. F. The spore discharge of the apple scab fungus in Dela- waree Delaware Agr. Exp. Sta. Bul. i140: ca 1925.
By and T. F. Manns. (Report of) Department of plant path- ology and soil bacteriology. Delaware Agr. Exp. Sta. Bul. 149; ed-29. 1925. Notes on the value of casein compounds: in connection with or- chard spraying.
4- Anderson, H. W. Apple and pear scab and apple blotch. Trans. I11- inois Sta. Hort. Soc. 53 (1920): 264-370. 1925. |
A. Bagenal, N. B., W. Goodwin, E. S. Salmon, and W. M. Ware. Spraying experiments against apple scab. Jour. Min. Agr. Great Britain 32: 137-149. May 1925.
Working on the susceptible variety Bismarck in England, they
10.
il.
12.
Keitt, G. W. Studies of apple scab inf
APPIE — Scab
found scab lesions on lcaves before blossom opening necessitat~ ing the application of a ges spray. Bordeaux mixture (€=8-100) snd lime sulfur (1 ~29) produced the best results, Lime~sulfur caused dropping of young fruits while Bordeaux mixture did not.
Ballou, F. H. and I. P. Lewis. Spraying for apple scab and apple. blotch. Ohio Agr. Exp. Stat. Monthl. Bul. 10: 50-52. Mare-Apr.- 1925- |
Birciinghan, W. A. Experiments for the control of black spot of due to the fungus Venturia inaequalis (Cke) Aderh.° Agr. Gaz
South Wales 37: 665- 606, Sept. 1925.
Biclaniay: H. “Gantrar of black spot Venturia inaequalis (Cke.}) Aderh. Agr. Gaz. New South Wales 36: 737-750. Oct. 1925.
Butler, O. Control of apple scab. New Hampshire Agr. Expe Stae’ Circ.
25; 1-0, 1925, Doran, W. Le Experiments on the control of apple scab and black rot and spray injury in 1924. Massachusetts Agr. Exp. Sta. Pulse 222;
1-10. 1925.
Primary infection of leaves was prevented equally well by lime-sulfur solution, Bordeaux mixture, and dry-mix sulfur-lime. The addition of calcium caseinate spreader to a jime+sulfur and lead arsenate spray did not result in increased protection against scab.
Frey, C. N. The cytology and physiology of Venturia inaequalis
(Cke.) Wint. Trans. Wisconsin Acad. Sci. 21: 303-343. 192A. Experiments thus far performed show that the minimal tem perature for infection is not more oh 6° oO. and the maximal: not less than 26° C. It is probable that fur ther work will ex- tend the lower temperature limit. ae ‘optim temperatire for infection was near 20° C. which agree args Sed with the optimum
for germination of ascospores and growtt q
and G. W. Keitt. Studies of spore dissemination of Venturia inaequalis (Cke.) Wint. in relation to seasonal develop- ment of apple scab. Jour. Agr. Res. 30: 527-5d0. -1925.
: ection under controlled ‘con- ditions. (Abstract) Phytopath. 16: 77. Jan. 1926. :
and E. E. Wilson. Studies on the developmer nt of: the
= 5 , ; 4
ascigerous stage of Venturia inacoualis in nature. ( ract} =F a = me
Phytopath. i6: 77. Jan. 1926.
Kendall, J. C. Toxicity of fungic Hampshire Agr. Exp. Sta. Bul. 2 197).
Doran (9) carried on experiments to determine the effect on:
Hig 78 APPLES -— Scab; Blotch spores of adding arsenious oxide, lead arsenate and calcium arsen-— ate to lime-sulfur solutions. It is reported that lead arsenate through its decomposition, and arsenious oxide increased the tox- icity of the solutions but the addition of calcium arsenate only slightly decreased the percentage of spore germination. 15- Salmon, E. S., and W. M. Ware. Biological observations on-apple "scab" or "black spot". Jour. Pomol. and Hort. Sei. A: 240- 2A9. June 1925. f = > a > 16. Schenk, P. J. Appel- en pereschurft. Floralia 46: 244-245. Apr. 7 Cj‘ (> 1925- i7- Stover, /. G. Apple seab costs Ohio 70; 000 bushels a year. Agr. Student Ohio Univ. 41: 104-185. Apr. 1925. IG. Thomas, P. He Black spot control. Tasmania Dept. Agr. Fruit Div. Buke 116: 1-6.) 16ebs 19. Black spot control. Fruit, Flower & Veg. Trades Journ. 8: 244-2556 Aug. 29, 1925- 20. Whetzel, H. H. The story of the apple scab and its control. Proc. : . _ = a New York State Hort. Soc. 70: 159-lo2- 1925- fl. Young, He. C. and R. C. Walton. Spray injury to apple. Phytopath. 92 405-415- 1925. BIOTCH CAUSED BY PHYLLOSTICTA SOLITARTA ELL. & EV. “ 7 * a
+
east of the Mississippi: A a the Mississippi and only one wes
Relative prevalence
considering the country as Jent in 1925 than in 192A and the With that of 192A, only inois, Indiana, Jersey reported less. |
— of the 1925 prevalence mal this year, while the & ler from
nce was reported ir
y Ohio and Tennessee reported Kansas, West Virginia, Virginia, Delaware, Wisconsin and Alebama
ma jority Maryland, }
ion of blotch was limited largely to t of the reports for 1925 came from ve reports was received from east of
a whole blotch was considerably less preva— average year. Comparing the 1925 prevalence more, while Kentucky, T11-— Maryland, and New reported the same as in 1924. A with normal shows that no state reported more of collaborators reported less. Yew Jersey, Tennessee, Wisconsin, and
- Nor=
eS Oe
: iF yc Try APPLE — Blotch
Loss
Losses
losses from blotch for 1925 were a minor consideration in fruit produc-— tion, the data indicating that they were considerably below normal, .and Since _ the apple crops in the blotch areas were smaller than usual the total aggregate loss in the United States was comparatively sitehte
Table 44. Estimated losses from blotch as reported by collaborators, menue
es | ae States-reporting-. ::Percentage: States reporting eS up ie eA LOSS 10 : Alabama |» es vale : Maryland, Indiana, A : Kansas, Kentucky | ss _( PEllinois, Arkansag- : : North Carolina, Iowa, :: -7/5 : New Jersey ; Tennessee, Mississ- :: trace : Delaware, Virginia, ippi © one. - pet : West Virginia, South -
aire oe ONTO, Texas “ Bue . ; Dakota, Nebraska
s ee °
West Virginia: Much more than usual on Ben Davis in Berkeley and Jefferson Counties. (Sherwood)
‘ Virginia: 4s prevalent as usual in infested orchards but not cheoked by the drouth as scab and other diseases. (Fromme) S
Oklahoma: This is probably the worst disease of the fruit, affecting fully 60 per cent of the fruit of Missouri eae Ben: Davis. in unsprayed orchards. (Rolfs) Ve
Arkansas: Very little in principal apple section in Washington and Benton Counties. Common at lower altitudes in central and said ern parts where little spraying is done. (Young) ees
Ohio: Blotch is more general throughout the southern part of the state. than it has been for several years and is seus considerable: loss « (Young )
Tllinois: Blotch was very late appearing due to dry weather and when | it finally appeared the few primary infections were not numerous enough. to cause loss. (Anderson) ?
Weather relations
* The lack of normal rainfall appears to be the most important factor in hibiting the disease this year. This lack of rainfall prevented the normad exudation of spores from the cankered twigs, resulting in a minimum of infeo-. tion. Young. of Ohio reports, "Unfavorable temperature relations." Gardner .of Indiana says, "Hot,:-dry April and May unfavorable." Anderson of Tllinois’ re: ports, "An ofpmomsly dry spring .resulted in almost pigs control of apple eam
APPLé - Blotch : ae
Dates and location of earliest renorted
April Franklin Co. Kentucky . June 11 Lawrence Indiana
May 18 Pulaski . Tliinois June 15 Holmdel New Jersey
June lexington Kentucky October 6 Wild Rose Wisconsin
June 5 Crozet Virginia
Spore emergence and infection data
New Jersey: Thirty apples were bagged each week starting May if and con— tinuing until June 40. On unbagged apples first infection was observed on June 22. All apples bagged on May 18 were cfean. Of hose bagged May 20, 1.1 per cent showed blotch, those bagged
June 1 showed 0.04 per cent blotch, while 50 per cent of the © fruit bagged on June 8 was infected. Most of the apples bagged after this date showed aoadgen van ene In this orchard the i7- day application was made on 26 and the 28-day spray, June 2h (Martin)
Virginia: Pirst fruit lesions noted at Crozet June 5 and at Winchester
June 12. Records of exudation of conidia from twig cankers ob-. tained at both Crozet and Winchester to date are as follows:
Crozet Winch ester
May 2A May 24
June 6 June 7
June 24 June 18
June 27 June 2A
ee July A
- (Fromme)
Varietal susceptibility
The data on varietal ei reed Was not specific enough to compile therefore, cuote the collaborators.
WNew Te = La a a ae ee 23 5 = 2 f - New Jersey: Most severe on Smith Cider. Found on Alexander. (Martin)
Wisconsin: Most noticeable on Northwest Greening and an unnamed yelloz sweet apple. (Vaughan)
Virginia: The only susceptible varieties found in Virgin nia are North— western Greening, Ben Davis, and Limber Twig. (| (Schne iderhan)
: Most serious on Dutchess, Early Harvest, and Ben Davis. Not serious where thoroughly sprayed. (McClintock) i In nursery. Early varieties most seas a hae (Fackler) ae
An interesting report on varietal susceptibility for 1925 was that of Gardner. He tsayst i
>=
"The mogt recent discovery is that of the presence of apple Rage blotth @ankers on = ench-grown seedlings. This at once raises a * ates aS-to whether or not this disease occurs in france."
ear) Se)
APPLE — Blotch Quoting the saine colleborator further:
"In addition to previous records, fruit infection has been found on Bald:7in and on twigs and:fruit of Cortlandt. We have Found blotch ..1 sevon nurseries in southern Indiana, on Kensas grown Svcedlings and on French secdlings in one nursery." —
Control data were reported from Virginia by Schneiderhan and from New Jersey by Martin.
It is apparent that in the New Jersey experiment, block 4, sprayed with 1~40 lime-sulfur, two and three weeks after petal fall, and with Bordeaux, four and six weeks after petal-fall, produced the best results.
Table 45. Biotech control results in New Jersey, 1925.
Clean : Salable : Unsalable
Block ¢ per cent : per cent ;: per cent Pe wae Pi Oke” meee awe awh So ae Drop _: te nner 108 2509 EPecpeeoresPigk 1: 00.s be db.A _ Drop : =- : =~ : == Cee a. icky ~naeees eS 1.6
Drop ; Foie : “On : ET. ieee sPick 2 | Agel || Sfai/gG.2 + <% au. 7 Drop : Sa or Check ....-Pick ; : : ae! Drop : cheat e Se! : ol All except the check plot received the @glayed dormant, pink, petal-fall, and 7-day applications of 1 to 40 lime sulfur. Block 1 received also an application of 1 to 40 lime~sulfur at 17 days: and 2-4-50 Bordeaux mixture 4 and 6 weeks after petal-fall. Block 2 treat- ed in a similar manner was given an additional appli- cation of Bordeaux mixture 8 weéks after petal-fall. Block 4 received 1. to AO lime-sulfur 2 and 4 weeks after petal-~fall, the 17-day spray being omitted, and * then received applications of Bordeaux 4 and 6 weeks after petal-fall as in the case of block 1. Block 4 Was sprayed with lime-sulfur 17 days and 4 and 6 weeks after petal-fall. (Martin)
| In Virginia the relative control values of the three important blotch Sprays Were determined. The program of sprays was as follows: Ten days «arter ‘petal-fall (lime-sulfur 1 to 40) ; four wecks (Bordeaux, 3-5-50) ; seven weeks (Bordeaux 3-5-50). Of the four plots used, one reccived all of the sprays and in cach of: the other plots one spray was omitted which cnabled us to check the control effected against the full program. In a fifth plot, dry-mix sulfur- lime was applicd three times. The control data follow: Pike
x
198 | re. | APPLE -— Blotch
Yable AG. The relative values of three blotch sprays on North~ western Greening Trait at Winehester,, Vireiniag 9c on
: Blotch-free fruit : Number of fruits
Plot : Spray omitted : (per cent) : examined * 1 +: 10-day (May 15) : 207 F691: 2 : A-week (June 2) 59 A : 2453 4: Y-week (June 29). ; 94..0 : 3094 4; None (full program): Saas : pul 5 : Full program (Dry- : 70 : 7276 mix only) : Check : 34.2 } A682
1. Four weeks spray most important for blotch control in 1925.
2. Dry-mix sulfur-lime not as effective as lime-sulfur and Bor- deaux this year. | see
4. Value of four weeks spray is correlated with conidial exuda= tion. It was the most important blotch spray because it nullified approximately 58 per cent of total conidial exu- dations. (Schneiderhan)
Delaware; Trees with twig infection carefully sprayed with Bordeaux _ showed no fruit infection. Dry weather against prevalence of the disease this year. (Adams) seu
indiana: Spraying at petal-fall two, four, and six weeks gave good control on Dutchess and Ben Davis in southern Indiana. Bor- deaux mixture 2-A-50 and lime-sulfur 1 to AO effective. Blotch was not at all difficult to control this season. Canker eradi- cation in young orchards gives excellent promise of complete elimination of the discase with indications that special blotch sprays may be omitted by the fourth year after the cankers are removed. (Gardner)
Guba (2), (Illinois) for the control of apple blotch, recommends prun- ing and spraying. All pruning should be done prior to the application of the dormant spray. For the dormant spray, commercial lime-sulfur 1 to 8 or copper sulfate 1 to 10 it recommended. The dormant spray is to be followed with two applications of lime-~sulfur at intervals of two to three weeks after petal- fall followed by three or four applications of Bordeaux mixture.
According to Ballou and Lewis (1)
"The three-year average per cent of sound blotch-free fruit produced on the seven plots on which Bordeaux of different strength was used are 97.8, 95.9, 99.1, 98.7, 99.3, 99.7, and 100 respect-— ime bye (ihe firet=plot, 97.0 per cent, was sprayed with 0.75-2.25-50 Bordeaux; the last, 100 percent, with 2-6-50 Bordeaux. .The three- year average for the unsprayed check plot is 14.7 per cent. The five lime-sulfur plots gave three year averages of 94.4, [6.7 98.1, 93.5, and 99.5 per cent respectively."
199 APPLE — Blotch
McClintock and Sherbakoff (4) recommend that for blotch control on early apples at least four summer sprays be applied beginning with the calyx spray and following at intervals of two weeks. Either lime-sulfur or Bordeaux if thoroughly applied should control blotch.
Recent literature on blotch
- eee eailou, F. Hy and —. Ps lewis. Spraying for apple scab and apple blotch. Ohio Agr. Exp. Sta. Month. Bul. 10: 50-52. Mar.—Apr. Sea | in :
2. Guba, E. F. Phyllosticta leafspot, fruit blotch, and-canker of the apple: lts eticlogy and control. Illinois Agr. Exp. Sta. Bul.
256; 481-557. 1925.
Be Heslety Le Ke Apple blotch control. Proc. Tennessee Hort. Soc. 19: £9-55. alge .
A. McClintock, J. A., and C. D. Sherbakoff. Spraying early apples for biotch control. Tennessee Agr. Exp. Sta. Bul. 142: 105 1925.
he Martin, W. H. Plant discases of New Jersey. VIII. Blotch. A serious disease of the apple. New Jersey Agr. 7 (12): 10-11. Dec. 1925.
6. Thomas, H. E. Apple blotch in New York state. Phytopath. 15: 246- C47. 19256
7. Walton, R. C. Apple Blotch.e Pennsylvania Agr. Exp. Sta. Bul. 196: ivest i) Tally’ 192%
CEDAR RUST CAUSED BY GYMNOSPORANGIUM JUNIPERI-VIRGINIANAE SCHW.
Geographic distribution
The geographic distribution of cedar rust as reported for 1925 was simi- az to other years. This, of course, is due to the peculiar nature of the dis- ease and is determined very largely by the distribution of the red cedar. Cedar Tust. infection in 1925 was exceptionally light. Only three states reported . @reater prevalence than for 1924 or normal. These states are Iowa, Minnesota, and Kansase
In Minnesota according to a letter from E. C. Stakman,
“The: explanation lies in the fact that we had tropical rains almost from June 1 to about June 20.. There was a total of 4.75 inches of rain during June,......-. There also were many minor showers, at least almost every day and sometimes several times a day. Not only that but there were rather heavy winds. The conditions, therefore, were ideal for the gelatinization of the cedar galls, for the germination of the teliospores and the distribution of sporidia.".
200 APPLE - Cedar rust ‘|
Considering the fact that twenty-—Tis that in! ming of them the disease was exce 1925 was year of comparatively slight in
jionalily slight, we perictiae kde I ection for the country as a whole.
hy bg oO ch <4
Tadle 4/7. Prevalence of cedar rust in 1925 compared with 192A and with normale Pah Compared= to, T9240 3 2 Compared to normal 2 More *" less” ¥.. Same. =:- Mores... tess 4 sees Minn. : Mass. : Conn. >: Minn. : Mass. : Conn. Iowa : Del. ; Ala. >: Lowa > Del. : Md. Kans. : Md. : hich. :: Kans. s Vae > Ala. == > Va, e Wise a eee x Ws Wee : Mich. —_ = W. Var ‘ Sot er ae . 3. Bare YT iss = S75. Gata = eee ks Be : Ark. 2 soles —= en Sat ee : Tenn. ee seat = (hs =: Ni Car: oe = hls {= 2200+ ae ie ale aes > Tenn. -- : Ohio > oo 2200-- gn Ld dee 2 oo -- s Ind. 2 = 2200 : oo :oo-- -- ae > -- 22 00-- : oo-- -) = Losses The average loss from cedar rust in the United States for the six-year period, 1918-1924, inclusive was approximately 1 per cent. The loss in 1924 is considerably below that average. Even in states where cedar rust is usu ally of great importance, like Pennsylvania, West Virginia, Virginia, Marylee and Ohic, the disease caused only slight damage in 1925.
mated losses caused by cedar rust in the United States
Percentage: States reporting ::Percentage: sates reporting loss : $3 loss : A ; Lowa :: trace : Maine, New Hampshire, 4 : Virginia BAe : Massachusetts, Rhode 1.5 : North Carolina 32 : Island, Connecticut, New B >: New York, West Vir- :: : Jersey, Deiaware, South ; ginia, South Dakota :: : Carolina, Ohio, Indiana, “5 : Connecticut, Mary— ais : <llinois, Michigan, Wis- > land, Minnesota, a : consin, Missouri, North : Kansas, Tennessee, :: : Dakota; Nebraska, Kentucky : Arkansas 5 : Alabama, Mississippi Okla-
Massachusetts: Crabapple trees which have been highly infected with ‘ Se = os ub a8 + a the disease bear very little this year. (Davis!
201 APPIE -— Cedar rust
Connecticut: Little scrious injury reported. (Stoddard & Hun )
age is very heavy in some orchards of Rome thy, York Imperial, and Jonathan. (Wagoner)
Delaware: Considerable reduction in prevalence during the last two ms )
Virginia: Caused considerable injury in orchards subject to severe ner
r = = ee { \ exposure of cedars but generally lighter than last year. (Fromme/ West Virginia: Much less this year than in 1924. (Giddings)
fruit spot and some serious leafspot and defoliation. 7 . ck)
5 = i, es S
ively little damage caused by this organism during ent year. (Rolfs)
Arkansas: Much Jess than last year. Not enough to cause defoliation in any isolated cases. (Young)
vy
~
ndiana: Light foliage infection; trace on fruit. Too dry in April am May. (Gardner)
kK4
: Rust has been observed as less thare usual this year at Gays ts Mills. (Vaughan) Minnesota: Considcradie rust on apples has been found in certain lo- Galities particularly Albert Lea, Taylors Falls, and Fillmore a o
eet. Plant Path.)
Missouri: There has been very little cedar rust this year. (Bregger)
——- +
Weather’ relations
With local exceptions, weather conditions
in the United States for 1925 Were very unfavorable to infection. The important factor, as in some other
diseases was the absence of normal rainfall, which in the case of cedar rust is necessary for t b
a the protrusion of the teleosori and subsequent production of spores.
Spore discharges
The following data relating to spore development were received from Je F. Adams of Delaware:
"“Teiia maturing on cedars April 24. Pycnia on leaves of Early Ripe observed May 7. Very little infection observed to date ( July 15) and considerable recuction in prevalence in last two years."
202 : APPLE - Cedar rust
From Virginia, which has for years reported the greatest economic loss § ’ : | Be
from cedar rust in the United States, the following statement concerning spore
discharges was submitted.
"A heavily infected small cedar tree planted in the laboratory ,
grounds at Winchester was used for demonstration of infection and
spore discharge. It was planted between two small York treés, one of Which was covered with a muslin bag, the other uncovered. Defoliation
to the extent of 80 per cent occurred June 15 on the uncovered tree. Removing the muslin bag July 19 revealed no infection on the covered
tree. This demonstration of infection was used to good advantage as propaganda for cedar eradication campaigns."
Table 49. The dates and the nature of discharges of teliospores from cedar tree galls, together with rainfall in inches, Winches- ter, Virginia.
Rainfall : Spore 4% « Ranma 5 Spore Date : (inches) : discharge :: Date : (inches) discharge April 2: -06 Sifent lb auey Sion 08 > Slight April LO: OA s) Shen t «= May LO: e15 : Medium April dA 250 sity HSS is geet My aoe 074. 2 *Heamy fora t Ake - LO : Heavy ee May 2A: ao ile : Heavy Koval 24 - LO : Heavy a2, Nel 2 219 © pagbetee Apr b Abs 98 .: Heavy :: June f : , 12 : Medium April 26: 10 ; Slight :: June 8: 50 : Medium April 28: yi : Heavy :: June ae 15 +: Medium Porat. 29 > «5 Soe eeany ven duney Lox «20 : Medium April 40: °59 : Heavy sir June, 25: 48 - Very. Mey 4° £0 e Heavy a : : slight (Schneiderhan
Dates and locations of earliest reported appearance of cedar rust, 1825
May ‘7 Seaford Delaware June 11 North Stonington ¢ Connecticut J May 11 Winchester Virginia June 11 Raleigh Nors Carolin Mey 20 Amherst Massachusetts dune 11 Knox County Indiana . May 25 Springhill Tennessee -June 24 Kandiyohi County Minnesota June g Orange County New York July 7 Shiloh New Jersey June 9 Clemson College South Carolina duly 20 Dartington Wisconsin
Varietal susceptibility
New York, Ulster County: On Rome Beauty, Wealthy, York Imperial, and Jonathan. (Chupp)
New Jersey: Found on Star. (Martin) Virginia: Susceptible varieties in Virginia are Rome Beauty, York In- perial, Jonathan, and Ben Davis. (Fromme)
APPLE -— Cedar rust
Tennessee; Less on Transparent, more on Early Ripe and Early Harvest. : MeClintock)
Wisconsin: Confined mostly to Wealthy as far as economic importauce is concerned. Found on twigs of Goodhue variety at Waterloo. (Vaughan) |
Minnesota: Ornamental crab (Pyfus ioensis) extremely susceptible. Twigs
s as well as leaves attacked. Wealthy most susceptible. (Sect. Plant Path.)
Control.
Such data as were received for control deal primarily with the eradica-— tion of cedar trees. An idea of the extent of cedar tree eradication in Vir- ginia will be gained from a digest of data furnished by W. J. Schoene, of the Virginia State Crop Pest Commission, under whose direction this work was car- ried out. This information is included here because it represents a successful effort on a large scale to eradicate: the intermediate host of a heteroecious fungus affecting apples.
"The total acreage reported cut over in 1922-1924 was approximately 200,000, at an expense to the growers of approximately $30,000. From 192% to 1925 an additional 61,817 acres were cleared of cedars. The cost of removing cedar sprouts during this period was $4,959.36. A most conservative estimate of the returns in increased production resulting from cedar eradication for one year (19243) is $500,000."
Virginia: Seasonal weather conditions will determine very largely the intensity of infection by cedar rust. In 1925 a safe cedar-—free zone was approximately two miles in extent. Cedar rust infection in 1925 was the lightest during the past four years. The two- mile zone would probably not be so safe in a year of heavy in- fection. Notable decrease of rust injury is found on apples with- in a mile of cedar trees.
Table 50. leaf infection of York in relation to distance from uncut cedar tree areas, Mt. Jackson, Virginia, 1925.
Distance. : Percentage of : Average number ©)
(miles) leaf infection lesi er leaf aa ~ 7 <3 - 11.7 pay fa0%, 343 3.10 2 ; 5762 A.%2 Bape" 20.0 : Ose
Spraying as a means of cedar rust control of apples is not practicable. Data prepared from plots of fully sprayed and un- sprayed Rome Beauty during four years, 1922-1925, indicate that no appreciable sontrol of cedar rust resulted from applying a full program of sprays. (Fromme & Schneiderhan)
204 APPIE. — Cedar rust; Blackrot
According to Schoene et al (4) it appears that orchards in which the av- erage infection does not exceed two or three spots per leaf will mature the crop normally. Injury is noticeable when the number exceeds three spots, even under favorable conditions for apple production. Serious defoliation and re- duction in crop occurs when the number of spots reach 8 to 10 per leaf, and as many as 20 spots per leaf produce such severe injury that the fruit stops grow- ing when about one-third mature.
Recent literature on cedar rust
1. Atwood, G. G. The red cedar (Juniperus virginiana). A menace to apple production in New York State. Circ. Dept. Farms & Mar-— kevs, New York 2775 tei2.. 1925.
2. Campfield, W. S. Cedar rust control. Rep. Virginia State Hort. Soc. 28: 33-30. 1924.
4- McCubbin, W. A. Apple rust and its control. Bul. Pennsylvania Dept. Agr. 3 (15): 1-10. Sept. 1, 1925. General bulletin No. Z1i.
A. Schoene, W. J., C.- R. Willey, and L. R. Cagle. Cedar_spots and ruit losse Quart. Bul. Virginia State Crop Pest Commission
6 (2): 1-86. 19252
5. Talbert, T. J. Cedar rust of apples in Missouri. Missouri Agr. Exp. Stas Circ.195: 1-8. Apr. 1925.
6. Waite, M. B. Apple cedar rust control. Proc. Ann. Blister Rust Gonf. 10: 9-44. 1925. ;
BLACKROT OF APPLE CAUSED BY PHYSALOSPORA MALORUM (PK.) SHEAR
relative prevalence, and irmortance
zeographic distribution
Twenty-seven states reported on blackrot in 1925. No radical differ-— ence in geographic distribution was noted. It may be stated again, however, that blackrot is more severe in the southern, south central, and eastern states where the temperature is slightly higher than in the northern states. Of the twenty-seven reports submitted, eight reported the same prevalence as in 192A, five reported less, and only two reported more. Those reporting the same prev-— alence as 1924 are Connecticut, Ohio, Michigan, ‘Minnesota, Iowa, Kansas, Tennessee, and Kentucky. Those reporting less are Delaware, Maryland, West Virginia, South Carolina, and Indiana. the two states reporting more were New Hampshire and Virginia.
In summing up the cepeesolganet on relative prevalence we conclude, that in 1925 blackrot was slightly less prevalent in the United States than in 1924 or luring the average year. Following are some of the. reports from collaborators.
205 APPLE ~ Blackrot
New Jersey: Blackrot is comparatively unimportant this year being re- ported only from a few orchards. (Martin)
Maryland: Plentiful in unsprayed or improverly sprayed orchards, es-— pecially where dead wood has not been pruned out. (Jearle)
West Virginia: Quite prevalent. (Giddings) " ee aiaeit pices has been a moderate amount of blackrot. (Bregger) Nature a in jury It was Showene worth while to include comments from cullaborators re-
garding the relative importance of fruit, leaf, and branch infection in their respective states.
New Jersey: Observed on leaves, fruit, and twigs. (Martin) Delaware: Slight leaf infection. Early fruit infection. (Adams)
Virginia: Blackrot injury in Virginia results from leaf and fruit in- fection, the latter being most important. A striking relation existed in Virginia between blackrot infection and fruit injury caused by codling moth. This insect was the cause of.the heav— fest losses to apples in Virginia in 1925. The heavy prevalence of bDlackrot this year is due very largely to worm injury through which the fungus gained entrance. A slight amount of blackrot infection also follows calyx-end injury. (Schneiderhan)
Tennessee: Leafspot, defoliation, and some fruit rot. (McClintock) Kentucky: lLeafspot quite common. (McGill & Valleau)
South Carolina: Cankers on nursery stock moderate. Fruit rot in or- Ghards slight. (Fenner)
Alabama: Leafspotting and defoliation. Some fruit rot. (Miles & Blain) Arkansas: Frog-eye leafspot very abundant on unsprayed trees. (Young )
Indiana: Fruit rot following bruises, haii injury, or worm injury. Some calyx infection. (Gardner)
Michigan: Cankers on limbs. faeitetes
Minnesota: Follows fireblight; slight injury to fruit.: No leafspot ~~ recorded this year. (Sect. Plant Path.)
Wissouri: In most cases blackrot follows hail injury. (Bregger)
Losses
- The losses from blackrot injury in the United States this year were less
than normal. The accompanying table 51 gives the percentages reported from the different states.
206
PLE. = Blachroy
Table hi... Estimated losses from Bisekrot as reported by collaborators,
Che vae rhe Percentage: States reporeugwercentaess ng wo LOSS td ee eos ae ee ee ——- : Termessee . eyo a va dar LC ema me it chews New Hampsnire, fs! a Mary Tad. ie > Vermont, New York, 5 2 Georgia, Lowa, Onto: =: ; New Jersey,-West Vir— 2 : Nortn Carolina er -° ginia, South Carolina, a) pe VL ei me 2 4% 2 a : Lllinois, Minnesota, i 2, VONnneCLicuL,. Meena sss > Kensas, Kentucky, 7 gan, Rhode Islade, <: - Colorado; euisiana; :. Mississippi :¢ : South Dakota, Cali- 05 > Delavare, .L mdi ane sue = |. > jx gue : Alabama | ee :
The effect of weather noted on other diseases of fruits applies also,uo biackror. “ Since spore ee results only from soaking of cankered twigs, the ;
vericdicity and emount of rainfall.in any locality will determine largely she Diackro®t infection, particularly on fruit which has been injured by in-— ee
New York (Wayne County): This disease is appearing in ee Amounts with the wet, weather, but it is mech less abundant than last Vege: te. ie Mills, New York State Coll. Agr. Weekly News
North Carolina; Less prevalent on account of drouth. (Lehman & Fant) fh : E :
Arzsansas: Not common this year in the apple section ‘of normwester Arkensas. The dry spring apparently unfavorable. (Young) -
Indiana: Dry April and May unfavorable. (Gardner)
A record of first appearances of blackrot as reported by the collabor-— ators follows:
Dawes anc Toeation. Or earliest rr
March 28 Rodman South Carolina . May 2 Mower ' New York April 23 Lawrence Indiana “May se - Columbia Count; New York pepe 27 ‘Blacksburg Virginia June 11 . North Stonington ‘Connscecm: May 10 Springhill — Tennessee July 14. Wilton New Hampshire
Varietal susceptibility
Delaware: Early Ripe leaf infection noted for April 22 and fruit in- fection (mostly calyx) July 9 at Seaford. Giada
, 207 ‘ APPLE - Blackrot; Bitter rot
Virginia: Mostly on Ben Davis; Grimes, Delicious, and Yorks following worm injury. Calyx injury caused by spray burn followed by blackrot. mostly in Ben Davis. (Fromme & Schneiderhan)
Tennessee: Rapeéial ly Bad Wafepot on Yellow Transparent and Dutchess. (McClintock)
-IAdiana: Frog-eye noted on Transparent and Rome. (Gardner)” Control Cee Oe Se talbedineelitliseniertoti bear ae According to, Doran (1)
"In the Baldwin orchard there were three times as many leaves with frog-eye leafspot on check trees as on those dusted with sulfur. In this orchard, 7.2 per cent of the fruit on the check trees became in- fected with blackrot, while the disease was present on only 0.9 per cent of the fruit dusted with sulfur." , ;
Attempts made to discover the causal pase a: ik eck in Pennsylvania were reported. by Walton (A) to be unsuccessful.
Fenner (2) has described a rot of apple which is very similar to black- rot, but which is caused-by Botryosphaeria ribis. Shear et al (3) have com- pared the morphology of this fungus and of Physalospora malorun.
Recent literature on blackrot —
1. Doran, W. Le Experiments on the control of apple scab and blackrot and spray injury in 1924. Massachusetts Agr. Exp. Sta. Bul. 222; 10 pp- (unnumbered). 1925. | Beh
2. Fenner, E- Aline. <A rot of apples caused by Botryosphaeria ribis. Phytopath. 15:-230-234. Apr. 1925.
4. Shear, C. Le, Neil EH. Stevens, and Marguerite S. Wilcox. Botryos- io, 8. and Physalospora in the eastern United States. Mycologia
7 98-107. 1925.
4. Walton, R. G. Black rot of apple. In Pennsylvania Agr. Exp. Sta. Bul. 196 (Ann. Rept. Director 1924-25) + 18. 1925.
—o ROT CAUSED BY GLOMERELLA Co a (STON.) SPAULD. & SCHRENK
During the past six years the data submitted by collaborators indicate » that Virginia, North Carolina, South Carolina, Georgia, Tennessee, Alabama, and Mississippi have suffered the most severe losses from bitter rot in the United States. The status of this disease in 1925 may readily be judged by the fact that none of the above mentioned states have reported more bitter rot than usual ard most of them have reported less. We infer, therefore, that this dis-
208 APPLE ~ Bitter rot
ease was not only below normal in prevalence,. but, that the economic*-. losses in the country Were srailler than usual. ,
The heaviest loss from bitter rot in the United States in 1925 was re- ported from North Carolina where this disease caused a total crop reduction of 4 per cent. Following is a brief table ind country in 1925. |
Table 52. Estimated losses from bitter rot as reported by collaborators, oO v= Percentage: States reporting s:percenvage: tates reporting
loss : a: loss :
3) : North Carolina :: ‘trace ; Maine, New York, Massa-
Es : Maryland We :. chusetts, Rhode Island, Con-
1 : Georgia, Alabama, Ohio, :: : necticut, New Jersey, West
: Tennessee ve > Virginia, Nebraska, South
5 7) Varernia, Pilinors a : Carolina, Louisiana, Ken- 025 : Delaware -f- > tucky, Arkansas, Kansas, ~L : Indiana =| : .South Dekota, Colorado
‘
(a= © ct @) tn $9
nd location of earliest appearance of bitter rot, 1925
March 26 Rodman South Carolina July 6 Knox County Indiana
May 16 Lawrence County Missouri August 8 New; Brunswick New Jersey
July -- - Tilinois August JG °"™seetore Delaware
July 4 Crozet Virginia September 4 Norwalk Connecticut No c
lear-cut statements concerning susceptibility or resistance of var- Ss were made. In-Delaware the disease was reported_.on King David; .in Vir— ippin, Ben Davis, and Smoke House; Indiana on Jonathan, Grimes,
ransparent, and Ben Davis. The worst infection, according to Gardner (Indiana), was found on low hanging fruit. TIllinois reported bitter rot on Jonathan, Sen
nad Grimes. fery few reports on weather relations were received. Only three states reported more bitter rot than last year then normal. These were Indiana, Ill- inois, and Maryland. In Indiana, according to Gariiner, "The high rainfall of July, August, and September was favorable to the disease." In Illinois, ac— cording to Anderson and Tehon, "Mid-season rains started infection but dry sum- mer prevented further infection and trouble." .
The following report on spore exudation was received from Schneiderhan of Virginia:
"The commonest method of over-—wintering of bit&er rot in Virginia is in’ bitter rot mummics. The remval of bitter rot mummies together with a few bordeaux sprays will easily control this disease in this state. In 1925 spore cxudation records were kept at Winchester. The Following table of this record is prescnted."
Healt, ° 209 APPLE - Bitter rot; Blight
Table §4 The dates and amounts of spore exudations from bitter rot mummigs, together with the rainfall causing these exu- dations, Winchester, Virginia, 1925.
—— i
: : Rernrakt Date : Exudation Pires fa oe
June 14 : Slight : abi
June 18 : Heavy : o2
June 24 : Heavy : A
SUAS ee! Heevy : 76
July A : Hoavy : 4%
July 15 ; Heavy ; -'70
July 21 : Slight : ~90
"In experimenting on the control valuc of bitter rot mummy removal
at Winchester, it was found in 1924 and 1925 that in spite “of careful demumiitecaticn of certain isclated Smoke House trees, the disease ap- peared in mid-season and caused a total loss in two large trees. This Suggested another means of carrying over the discase. An examination
ase of twigs just above heavily infected apoles showed a somewhat cankercd condition, although the term 'cankert docs not describe the corditions of these twigs, which were roughcned-with partly ore bark. AS a result of inoculation experiments it was proved conclusively that these twigs were infected. This is the first report of twig infection of bitter rot north of South Carolina. Further investigat: in Virginia Will be conducted next year in an cffort mine,
ditional varietics in which the bitter rot fungus is ca only in mimmics, but also in twigs."
BLIGHT CAUSED BY BACILLUS AMYLOVORUS (BURR.) TREV.
This disease appeared in cpiphytotic form in a large number of states this year. It was particularly severe in the largest apple production soctions of the country, like New York, Michigan, Washington, and Oregon, but exception-— ally heavy loss was reported aiso from such southern states as Georgia and Alabama., :
Of tne states reporting on the prevalence of blight this year, fifteen reported more than in 1924, nine reported lcss, and seven the same» Compared to normal prevalence, twelve reported morc, ten less, am five the same. We infer, therefore, that the average prevalcnce in the United States is not only greatergthan that for 192A but also greater than normal. .\ better idea of the Situation in the various states can be gained from the following quotations.
Massachusetts: Severe blossom and twig infection throughout the state.
Quince scems to suffer more than apple. Relatively little on pear. (Osman & Davis) | |
Now York: Extremely severe on apples and pears this year over the cn- tire states (Chupp)
210 ‘ APPIE — Blight
Delaware: Much less than Jast year. Appeared last week of May and very little spread observed. (Adams) ‘
Virginia: Slight injury. First appearance, May 10 at Winchester and Crozet. Said to inereasc rapidly for about a week, but after that subsided with comparatively little injury. atermed
p aS aD West Virginia: About as usual; no serious outbreaks. (Giddings) south Carolina: Present in about the usual amount. ( Ludw ig)
Georgia: in spite of extremely dry weather blossom—bli ght on apples eems to be unusually bad this vear. oe s)
Oklanoma: ing infections abu ee: on Jonathan and Een Davis early in spring. Leaf infections were abundant in June, but since then they have gradually ae speared without material damage. (Rolfs)
Arkansas: Severe on several varieties. Appeared later than last year and continued later. In general not so Severe as last year but ° é = \ more important. (Young) Tilinois: Extremely bad throughout state. .Worse blossom blight in ten
years. (Anderson) Indiana: Very serious. (Gardner)
Michigan: Blight is everywhere present and has caused heavy loss. ‘There appeared to be an unusually high percentage of cankers active in
the spring. (Bennett)
Wisconsin: Additional reports indicate fireblight to be more widespread and destructive than for many years. t is causing great damage to home orchards. (Vaughan)
Minnesota: Unusually severe on all susceptible varieties throughout the state. The most susccptible varieties of apple are gradu-— ally being kitled off. Hxcept for fireblight apples were very free from dissase this year. (Sect. Plant Path. )
Missouri: Fireblight of apples has been particularly severe this season. (Bregger)
Nebraska: Much more prevalent and worse than last year. (Peltier)
Kansas: Unusually severe this spring. Worse damage in older orchards. . This year's crop was decidedly reduced due to blossomblight and y p 5 & next yearts Ce a hancicapped due to spur blight. Loss con- servatively estimated at 5 per cent for the state. (White)
Oregon: In the } Milton-Freewater district it occurred in all orchards and on practically all varieties. (Barss)
The relative prevalence of blight is shown in table Ay
: 211 APPLE ~ Blight
Table 544 Relative prevalence of apple blight in 1925 compared with 1924 and average yeare
: Prevalence compareds: : Prevalence compared State : with =e State : with
: : Average :: : : Average
: ear Ae : : ear Connecticut : same : same ‘is et Lines : same : more New York ~ more : more :: Michigan : same : more New Jersey - same ; less :: Wisconsin - more : more Delaware : less ; same :: Minnesota : more : more Maryland : less ; less :: Lowa ; more > ---- Vimginia : less : less >: Missouri : same 2 0o---- West Virginia : more : less :: South Dakota : less : dless Kentucky - more : more :: Nebraska : more 2 ea Tennessee : less : less :: Kansas : more : more North Carolina : same : same :: Montana : less : less South Carolina : less : less :: New Mexico : more : same Georgia : nore : more :: Idaho : less : Jess Alabama ; more soe :: Washington : more : mere Arkansas : less : same :: Oregon : more : more Ohio : more : less :: California : game : same Indi ana ; more ; more ay : =
: Me: SRE Sar N IE : :
.-- = me eo ew mie
res
Blight was reported on all parts of the tree except the roots. The severest losses occasioned this year were apparently in the form of blossom and twig blights. Although in some states severe blight cankers resulted and in Minnesota entire trees were killed, the disease caused the most immediate injury in the form of blossom blight which preventcd the setting of fruit. It is apparent that unusually heavy twig infection in 1925 in conjunction with favorable weather conditions in 1926 will result in a very severe loss next year if weather conditions are favorable.
The losses from fireblight for 1925 were very heavy throughout the coun- try. In certain states, particularly Minnesota, New York, and Michigan, it wa: nearly as important as scab.
Table 5)... Estimated losses from blight as reported by collaborators, 1925. |
Percentage: States reporting ::Percentage: | States reporting
loss : 23 loss 8 : Michigan, Kentucky = ee | : South Carolina, Ark- 7 : New York eve : ansas, Washington, o : Minnesota, lowa, Kan- :: * Oregon sas, Mississippi 2: 025 : Connecticut 4 : Maryland, Wisconsin :: trace : Maine, New Hampshire, 4 : North Carolina, South :: : Vermont, Rhode Island, : Dakota, New Mexico zt : New Jersey, Delaware, 2645 : Alabama 2: : Virginia, West Vir- 2
+: Indtang, Eldineis, a : ginia, Georgia, Idaho, : Ohio, Texas : Montana, Wyoming ,Colorads
A ee em .
ae APPLE - Blight ~
“The record of the’ ot a appearance of bl ight | in 1 the various ‘states in jen is an Abe 5
Pe th ee . a re ce . ame OL SEES ht Y " +
Maron” penede Alabama May 19 Westminster South Carolina April 10 Knoxville Tennessee ¢ May a wMlassauiy-" Delaware
April 20 Anna _ Illinois | (May 26 Mower County Minnesota
May Columbia Missouri: - “June Habersham’ ~~ ~Georgia
fay Lincoln Nebraska June 2 Shiloh New Jersey May 10 Winchester Virginia June 24 Unionville . Connecticut May 11 Genesee New York
Control
Wisconsin: Door County fruit growers have organized a campaign to eradi- cate the blight by severe pruning in badly blighted orchards near Fish Creek to protect the large noldings, at St curgeon Bay. (Vaughan)
Barnett (1) reports the results of treatment ina Tonaeiaen necheae heav- ily infected with fireblight. The infected parts of the trees were excised and the wounds disinfected with Reimer's combination of cyanide and bichloride of mercury followed by the application of a mixture composed of one part water in
hree parts waterglass. Only 21 out of 574 wounds thus treated showed evidence of active infection when inspected. The article emphasizes the importance of eliminating hold-over cankers, planting resistant varieties, retarding ithe rate.of twig growth, and controlling«insect pests, particularly aphids.
fn outstanding contribution to our knowledge of the cytology and over~ oe ees habits of Bacillus amylovorus resulted from the investigation of Nixon (2). An abstract of his paper presented at the Kansas City meeting has Deen printed in Phytopathology.
Recent literature on blight
ie Barneua,) Re ds; aur scasons! work with fireblight on apples. Proce Amer. Soc. Hort. Sci. 21: 292-296. 1925.
ee Nogen,. be due Migration and trancformation of Bacillus amylovorus
in apple tissue. (Abstract) Phytopath. 16: 7[* Jane 1926. Se. Beals da Le ApPLe plight, question end answer exercises Minn. Hort. 54: 172-174. June 1965+
A, Talbert, 2. 2d. mere blight oa apples and “pears. , Missouri Agr. Exp. Stas Cire: 137: PB rece TAL G..19 ane: SR aE Se
BLISTER CANKSR CAUSED BY “ae Meine DCE ele TUL.
The nature of this disease is such that wide variations in its preva- lence cannot be expected. Blister canker in the United States may be said to be a typical Ben Davis disease, EI ii) in old orchards, since very few of the other important sole aut varieties seem to.suffer from it. Iv is a well-known fact that in years, of e2 cbreme drouth _ severely cankered trees
F — as Pw.s - . Pe Seem es i bah? dan -
215 APPLE - Blister canker; Fruit spot
will show greater evidence of injury and the rate. of killing of severely in- feeted trees will be greater than in years of average moisture. This fact was very noticeable this year in Virginia, according to Fromme who reports on this disease, "Unusually noticeable because of dry season."
Nothing new can be added to the general data on this disease as re- ported in previous supplements. Comparcd to last year the prevalence was practically the same. Of the cleven states reporting on this disease, ten re- ported the same prevalence as 1924 and one other reported less. Only Virginia, Illinois, Kansas, and Tennessee reported blister canker to be important in 1925
Delaware: Generally prevalent in neglected trees. No noticeable in- crease observed. (Adams)
Tennessee: Important in neglected orchards. Observed only in eastern Tennessce. (Peacock)
Oklahoma: & ‘ee. conmon Bape ake in many of the orchards of the state. (Rolfs)
Arkansas: Becoming less. important as susceptible varieties like Ben Davis are being eliminated. Better care of orchards also ef- fective. (Dept. Plant Path.)
Tilinois: Worse on Ben Davis, especially in the western portion of Bie ine state where Ben Davis is the main crop. (Anderson & Tehon)
Kansas: Important. Ben Davis seems to be most susceptible. eaiehen discase on account of killing older plantings. (White)
Losses
Only five states reported losses, among them New York, Maryland, Tenn- essee, and Virginia reported a trace, while Illinois reported 1 per cent. No information was reccived relative to control’ measures.
FRUIT SPOT CAUSED BY PHOMA POMI PASS.
Fruit spot was negligible in Peete ub in the United States this year. Only seven states reported on its relative prevalence while eleven simply re- ported it to be present. During the past five years this discase has been of considerable importance in certain states. In favorable years it is one of the important discases of applcs in the Hudson Valley, but this year no re- ports were reccived from New York.
From the limited data available.for 1925 we conclude that fruit spot was unusually late in appearance. According to Martin of New Jersey, "In most cases the disease did not appear until after harvest. This discase was not Severe if the apples were placed in storage." From Delaware, which has for Several years reported considerable loss, only a trace was reported for this year on the late crop. According to Young of Arkansas, "Less than usual at this time. Dry spring apparcntly unfavorable." Michigan reports it to be of
214 | APPLE — Fruit spot; Bitter pit
"minor importance." Vaughan of Wisconsin states, "None seen or reported." Ac-— cording to the Department of Plant Pathology (Weshington), "Not reported but known to occur in the central and eastern Washingten apple Section."
Delaware, Maryland, and West Virginia reported a trace of loss, while in Ohio and New Jersey -5 and .25 per cent respectively was estimated.
BITTER PIT, NON-PARASITIC
Bitter pit is one of the few diseases reported in 1925 to be of greater prevalence than in 1924 or in the average year- Fourteen states reported on this disease, eight of which reported more than in 1924, five the same, and only one less. The states reporting more were New Hampshire, New York, Indi- ana, Michigan, Idaho, California, and New Jersey. Those reporting the same prevalence as last year were Connecticut, Maryland, West Virginia, Ohio, and Minnesota. Only Kentucky reported less.
serious losses were reported from vhio, Indiana, Virginia, Michigan, and California. In the last mentioned state, the entire crop was ruined in some orchards. Only three states reported data on losses. These were Virginia, 5 per cent; Maryland, -5 per cent; and West Virginia, 1 per cent. The follow-— ing dates of first appearance of bitter pit were received.
Dates and location of carlicst reported appearance of bitter pit, 1925.
_—=<
August & Wilton New Hampshire September @1 Wallingford Connecticut August 20 Saugatuck Michigan september 27 St. Paul Minnesota September 1 Gatlinburg Tennessee september 40 Orange Co. Indiana september 5 Winchester Virginie . October 6 Flemington New Jersey
Only four states reported on varictal susceptibility to bitter pit. In Virginia this disease is most important on Yorks. It also affects Ben Davis and Delicious. In indiana it was serious this year on Stayman and Delicious. Michigan reports bitter pit on Baldwin.
It is usually assumed in the literature on the subject of bitter pit that the sunken spots and the laying down of the corky tissue is the result of an improperly . «balanced water supply. Various theories have been advarced to explain the development of this disease. In view of the comparatively heavy prevalence in 1925 it seems reasonable to assume that the abnormally deficient rainfall in the states reporting the heaviest losses from this disease is the important factor. :
Virginia: The unusually large York fruit in the upper Valley of Vir- ginia were particularly subject to bitter pit injury in 1925. York is the most important commercial variety in this section and by far the most susceptible to bitter pit injury. Seasonal conditions in this state were such as to cause an unusual early sizing up of fruit. A large percentage of Yorks were of normal size on September 1 but considerable growth took piace after that date. The Largest sized fruit produced in four years was the result. (Schneiderhan)
APPLE ~ Jonathan spot; Crowngall JONATHAN SPOT, CAUSH UNDETERMINED
This disease was slightly more prevalent this year than last. Although it is not a serious factor resulting in large general losses It is important Jo¢alily. Idaho, which pracueqeiaer third largest crop in the United States in 1925, reported more Jonathan spou in 1924 and also more than normal. None of the-states reporting indicated that this trouble was of great importance in iJeaj. lowe irepor Us tat ah was a iserisusi factor in stored: Truit.. In) Tennessee Baskin stated that it occurred only in storage. In Minnesota, according to the Division of Plant Pathology, it was in a few orchards of Wealthys only- Hunger~- ford of Idaho reports that it was more imoortant than usual and appeared earlier
CROWNGALL CAUSED BY BACTERIUM TUMEFACIENS EFS. & TOWN.
From the reports of collaborators in 1925 we infer that crowngall preva- lence in the United States this year was about the same as last year and as in normal yearse Kansas reports 25 per cent of nursery stock infected by this dis- ease in the Kaw Valley. As in previous years it was reported chiefly from those states in which the nursery business is important. A Few quotations from var-
lous collaborators follow: ;
Tennessee: On one-year old trees 15 to 20 percent, on two-year old trees ~ 60 to 70 per cent. (Fackler)
Arkansas: Nursery losses great. Not certain how much of this is true
crowngall. (Dept. Plant Path.)
Wisconsin: yr. A. J. Riker who has inspected the largest Wisconsin nur—
series reports more of the bacterial gall than usual with. much less of the excess calius or root knot. (Vaughan) . Fi S = © = 1+} 1 tr 6 Ge Minnesota: Found where the apples are grown; mostly in the lower two thirds of the state. (Dept. Plant Path.)
Crowngall surveys
During the fall of 1925 A. J. Riker of Wisconsin and J. H. Muncie of Towa made surveys of nurseries to ascertain the amounts of excess callus, true bacterial gall, hairy root, and gail and root knot found on nursery stock.
The generel notes of Riker's survey prepared from nursery inspections in Michigan, New York, Connecticut,, Pennsylvania, Maryland, West Virginia, Ohio, and Indiana and submitted to the Plant Disease Survey is as follows:
1. “Bacterial gall was widely distrituited but was present on only avery small heedees of the trees examined except at one Nursery in
Michigan.
216 APPLE — Crowngall
2. “Much less excess callus was found on apple where budding was practiced. in contrast with places where grafting was done, except in three nurseries where unusual care was taken to make well—fitted grafts.
4. "In general the amount of root knot on apple in the northeast Where the practice of budding predominates is much less than in the middle west where grafting predominates.
A. "Grafting of apple trees has been largely discontinued in the northeast because of the larger amount os root knots and less well- developed root systems which develop on grafted stock.
5» “Bacterial gall was found widely distributed on peach, but with the exception of one none was present on only a very Pleas per- centage of the trees examined.'
Muncie's inspections were made in Iowa, Kansas, Missouri, Indiana, New York, Virginia, Tennessee, and Alabama. The summary of his observations fol- lows ‘
1. "True crowngall was as widespread in the eastern and. southern states visited as in the central western states.
2. "With the exception of one nursery, non-pathogenic knots at the union of grafted trees was also as Widespread and as frequently found as in the middle western nurseries.
%. “Budding is more generally practiced in the eastern states and this reduces losses due to callus knots on apple.
"True crowngall on peach was oa in every nursery visited but only in slight amounts.
5. “Hairy root on budded apples was abundant in all nurseries visited but especially so in the southern states. This appeared for the most part to be non-pathogenic. No manifest&tion of hairy root was seen on peach."
Crowngall investigations
Studies on the relation of crowngall to apple nursery stock have been continued in Iowa and Wisconsin. Riker and Keitt (4) report:
"Tsolation stydies were made on 227 apple trees, representative of lots of stock submitted as crowngall rejects by 12 nurseries in six states. Less than two per cent of these trees yielded Bacterium tume- faciens Smith and Tom. Tests of the isolation technique on n known crowngall material gave positive results from 4A to Ab plants. A study of the trees which failed to yield the cromegall organism showed most of the malformations to be associated with pooriy fitted grafts. ‘Various types of misfittcd grafts were grown experimentally in com-
i oo : 9 .
APPIE -— Crovmgall a
parison with well-—fitted gra¥ts. Malformations could be induced or pre- vented almost at will by the tyne of fit. An examination of samples of freshly prepared commercial grafts from cight nurseries showed misfits in sufficient numbers and types to account for all the root knot re- ported by these nurseries. The following types of misfit appear to
jead commonly to the more severe callus overgrowths: cion tip long, cign Jarger than stock, graft too loosely wranvped. Wrapping grafts with clotl Waxed paper, or medical adhesive tape reduced the amount of callus de— velopment. The results ths far available give promise that the major portion of the callus overgrowths at the unions of grafted apples may be prevented by modifications in grafting practice."
Muncie (2) says:
"Three distinct types of hairy root have been observed on French apple Pagis es namely: (1) the woolly:knot form, arising from a dis- tinct gall; (2) the simple form Hees by Stewart; (4) the type in Which fine fibrous roots arise in clusters from the tap root."
The same writer (4) reports:
"Work has been continued on water donduction in galled and normal piece-root grafted ttfo-year cut-—back Wealthy, Jonathan, and Salome apple. The reduction in water flow through galled Wealthy, Salome, and Jonathan trees was 69.7, 21. {, and 47.2 per cent respectively. Lateral roots arising from above or opposite the gall may in some cases counteract the oostruction offered by the gall. |
"Young tomato plants were set in-soil infested with Bacterium tume- faciens and inoculated by injuring the stem at the surface of the soil and smearing the wound with the infested soil. Typical crowngall re- sulted up to 102 days after infesting the soil."
According to Sherbakoff (6)
"In a single experiment sulfur applied at the rate of 600 pounds pe: acre appeared to reduce the number and size of the crowngalls produced on nursery apple trees. The sulfur was applied t6 alternate rows and thoroughly mixed with soil in the furrow before the grafts were set."
Waite and Siegler (7) have reported on control by aise soa treatment of pe grafts; ‘ . Ssaglie dey. Semone
"In the experi ments of 1925 the organic mercury treatment was given
2,169 grafts, representing a number of different Varieties with the sean that the total number of trees obtained at digging time wi*h both large and smail galls amounted to 6. ‘ per cent, as compared with 32.6 per cent on 2,019 untreated grafts of the same veneget es which were used as checks. The proportion of the total number of gails in the grafts of all varieties was 2 per cent and in the untreated or checx grafts 28. 7 per cent.
"The following treatment of apple grafts for the control of crown-— gall is recommended as a result of a large number of experiments over ¢é number of years: ;
218 Sy 4 APPLE -— Crowngall
"(1) Select seedlings free from hairy-root and crowngall infection.
"(2) ‘After washing,: dip for 10 minutes uncut. seedling and scions in a solution consisting of one part of hydzoxymercurichlcrophenol* to 400 parts of water (approximately at the rate of one ounce to three gallons}. In this as well as in subsequent dips do not rinse with water, and kecp the solution in cither a wooden or a nonmetallic con- tainer.
"(3) Dip the grafts, which shouid be well fitted and carefully wrapped, in this same freshly made solution for about five seconds.
"(A) Store grafts under cool conditions and dip grafts for about _five seconds in a freshly made solution of the mercury compound immedi- ately before planting.
"(5) Keep the bench on which the grafting is done, as well as-all grafting tools, disinfected by frequent washings with a germicide."
*Obtainable on market in powdcred form under the trade name "Semesan."
Recent literature on crowngall
1. McClintock, J. A. Progress report on crowngall experiments con-— ‘ducted at the University of Tennessee Experiment Station. Proc. Tennessee State HoSt. Soc. 19: 66-88. 1924.
2. Muncie, J. H. Hairy root of apple seedlings. (Abstract) Phytopath. 1G? AVG. Man. 1926.
ae iin The effect of crowmgall on young apple and peach trees and longevity of Bacterium tumefaciens in the soil. (Abstract) Phytopath. 16: 79. Jan. 1926.
A. Riker, A. J., and G W. Keitt. Studies of crowngall and callus ‘ overgrowths on apple grafts. (Abstract) Phytopath. 16: 73 Jane ae
De Crowngall in relation to nursery
stock. Science 62; 184-185. Aug. 21, 1925.
6. Sherbakoff, C. De Effect of soil treatment with sulfur upon crown- gall in nursery apple trees. Phytopath. 15: 105-109. 1925.
(: Waite, M. B., and E. A. Sicgler- A method for the Saget of crown- gall in the apple nursery. U. S..Dopt. Agr. Cir. 376 : $86. Sian 1926.
APPLE - Sooty blotch; Flyspeck; Powdery mildew
SOOTY BLOTCH AND FLYSPSCK CAUSED BY GIOFODES POMIGENA ei yo Ag Sx COLBY AND LEPTOTHYRIUM POMI (MONT. & FR.) SACC
Only cight states reported on sooty blotch in 1925. This disease al- though of minor importance in the country as a whole has been known to cause serious losses in certain lecalities. On certain varieties like York, Stayman, Black Twig, and Ben Davis, it is serious in poorly sprayed orchards in Marylenc, West Virginia, and Virginia.
Connecticut reports more sooty blotch than in 1924, Delaware reports less Virginia more, and Wisconsin the same as 124 No state reported more tha normal prevalence in 1925.
The following statements describe the disease status in certain states:
Connecticut: More than average year with prominence gaincd toward end
of season on light skinned varicties. (Clinton)
a
A
Virginia: General and important in poorly sprayed orchards. «a common cause Of culls. fEohne sidernan
Indiana: Serious in unsprayed orchards. Worst on light colored varie- ties such as Grimes and Northwestern Greening. (Ga ardner)
Michigan: About as usual, found mostly on Talman Sweet (Tollman) variet. in unsprayed orchards. (Vaughan)
Minnesota: Considerable blotch developed in the Albert Lea section. It Was present on ail varieties, but most conspicuous on Greenings.
(Sect. Plant Path.)
Dates of earliest reported appearance were reported as follows:
August 19 Wyoming Delaware September 10 Winchester Virginia September 22 Milford Connecticut
Recent literature
1. Kendall, J. C. Sooty mould. (Data from work conducted by 0. R. Butler). In New Hampshire Agr. Exp. Sta. Bul. 216 (Rept. of
Director 1924); 14-15.. 1925. §
POWDERY MIIDEW CAUSED BY PODOSPHAERA LEUCOTRICHA (ELL. & EV.) SAIM.
s
Although this disease is of minor importance in the United States it has been known to cause scrious losscs on certain varieties. The Jonathan s
be particularly susceptible to powdery mildew infection and this varicty been known to be severely injured as a result of twig growth following the killing of terminal leaves. Twelve statcs reported on powdery mildew in In regard to the prevalence of this disease compared both with 1924 and
220
APPIE -~ Powdery mildew; Rootrots
normal, three states, Velaware, Indiana, and California, reported greater preva-— lence; three, Connecticut, New York, and Oregon, reported less: while Maryland,
Virginia, West Virginia, Michigan, Wisconsin, and New Mexico reported the same prevalence.
Powdery mildew is an early scason discase as will be indicated by the dates of first appearance.
Dates and location of carlicst reported appearance _ of powdery mildew, 1925
Mey 1 Winehekter: Virginie June 4 Mt. Holly New Jersey May 7 Yalesville Connecticut July. 24 Hennepin County Minnesota May 18 Dutchess County “New York eek 28 Gibson County Indiana May 22 Bridgeville Delaware
Notes from collaborators
New Jersey: Powdery mildew was found in abundance on Rome Beauty in - Burlington County. (Martin)
Delaware: More general than usual. Common on Stayman, Rome Beauty, and Transparent. (Adams)
Virginia: First observed May 1 at Crozet and caused some local injury there and at Winchester; especially on Jonathan and Stayman. (Frome) :
“Tennessee: Fairly important. Causes leaf and twig defoliation. Con- fined to Rome Beauty and Jonathan. (Baskin)
. Minnesota: Causes partial defoliation in nurseries. Chiefly found on young trees in nurseries. (Dept. Plant Path.) 3
Black rootrot caused by Xylaria spp.
i. is very probable that black rootrot is more prevalent than the usual stimates would seem to indicate. It is particularly prevalent in the south- ern states where it sometimes causes severe losses in old orchards. The follow- ing reports throw some light on the status of this disease in 1925.
Virginia: Percentage of tree death greater than in normal years. The dry season evidently caused many trees to die during the year wnaich would ordinarly have survived for another year or so with normal rainfall. (Fromme & Schne iderhan)
Kentucky: Very important; widely distributed. Perhaps 1 per cent of trees dying per year. (Magill & Valleau)
3 oe APPLE -— Roqtrots; Frost injury
Tennessee: More Xylaria than last year. Trees die while leaves and fruit remain. Found on Ben Davis and Grimes. (Baskin)
Mushroom rootrot caused by Armillaria mellea Vahl) Quel.
This is another minor disease of apples. Only two states reported losses in 1925 and these were New York and West Virginia, both reporting a trace. Sixteen states prepared a report on this disease and of these thirteen reported it to be unknown in the state.
Other rootrots Ozonium omnivorum Shear was reported by Taubenhaus as "Very important in
the black lands of Texas, where apples cannot be grown on account of it." Undetermined rootrots of various types were reported from several states.
FROST INJURY
From the data submitted by the collaborators, shown in the accompanying table, frost injury in certain states was by far the largest factor causing loss to apple production this year.
Table 56, Estimated losses from frost injury as reported by collaborators, 1925.
- Percentage: State reporting loss : 80 : South Dakota 50 : Lowa | 49 : Virginia 25 : West Virginia, Maryland, Minnesota 20 : Ohio 10 : Michigan
Delaware: Frequent frosts occurred during Avril. Blossoming varieties hurt mostly. (Adams)
Virginia: frosts on April 21 with a temperature of 28 degrees were gen- eral in the Vailey of Virginia and caused a loss of AO per cent. The blossoms were killed, leaves severely injured, and the fruit showed a high percentage of russeting and frost rings. (Schneidernan)
Indiana: Frost May 25 was very serious. Worst russet and lopsidedness of Ben Davis resulted in southern Indiana. (Gardner)
Illinois: General frost May 24 and 24 caused serious losses in all sections of the state and deformed apples were common due to the advanced stage of the fruit. It was not generally killed outright. (Anderson)
eee APPIE - Frost injury; Hail injury; Other diseases
Minnesota: Frost tended to thin amount of fruit on trees, but did not cut down crop as much as at first supposed. (Div. Plant Path.)
HAIL INJURY
Severe losses were reported as a result of hail injury in Connecticut, West Virginia, Virginia, Minnesota, and Iowa. From Virginia, Schneiderhan re- ports the following:
"Hail losses throughout Virginia have been so severe locally during the past four years that all insurance companies have been doing busi- ness at considerable loss. The result has been the rapid increase of premiums for this type of insurance. The largest single hail loss on apples ever adjusted in the United States occurred in an orchard near Mt. Jackson, Virginia. This orchard was insured for nO, O00, and as a result of an 80 per cent adjustment the insurance company paid to the
owner $53, LOY 65."
OTHER DISEASES: AND INJURIES’
There are very many miscellaneous diseases and injuries of apples of con- Siderable importance locally but unimportant from a country-wide standpoint. It is manifestly impossible to go into a detailed description of some of these dis- Gases in a) summary ‘or this*krne, therefore, we shall give brief quotations from collaborators Gy Le them and give a list of the recent literature , with them.
Alternaria sp., blossom-end rot - New Jersey.
Botrytis sp., fruit rot.— Washington.
Cephalothecium roseum Cda., pink rot — New York.
Cercospora mali Bll. & Ev., leafspot - Texas.
Coniothyrium sp. - reported from Washington.
Gloeosporium perennans Zeller & Childs, perennial canker.
For some years difficulty has been encountered in controlling what was thought to be Neofabraeca malicorticis in certain orchards in the Hood River Valley, Oregon. It has now been ascertained that at least one of the reasons for this is that there are the two distinct but similar forms. One is the common Neofabraea and the other a new fungus (Gloeosporium ee oe & Childs.) For the disease caused by the latter Zeller and Childs (50) have pro- posed the name perennial canker. | The known distribution of the disease ranges from the Okanogan Valley,
British Columbia, to the Willamette Valley, Oregon. It has also been reported from the Spokane and Wenatchee Valleys in Washington, and from certain stations along both’ sides of the. Columbia River and especially the | Hood River Valley where it has spread rapidly. It causes serious damage in some localities.
Neofabraea malicorticis (Cordley) Jack., anthracnose — Washington and Oregon. According to Zeller (Oregon), growers spray to control it, so there is comparatively little loss in the better commercial orchards.
22% APPLE - Other diseases
Nectria galligena Bres., Huropean canker - New York, Maryland, Washing- ton, and Oregon. It was of no great economic importance anywhere.
Penicillium expansum, rot - causing loss in transit, Texas.
Phytophthora cactorum (Leb. & Cohn) Schroet., rot - New York and Indiana. According to Gardner (Indiana), "It is rather serious locally. High rainfall favorable. Noted first on drops under trees, later in the packing sheds.”
Valsa leucostoma (Pers. Fr., dieback — Missouri.
Volutslla fructi Stevens & Hall, rot - West Virginia.
Measles (undet.) reported from New Mexico and West Virginia. According to Leonian, (West Virginia), measles were found in two orchards and were con- fined to Delicious trees. The-disease apparently spread very slowly in these orchards, as in the last four years it has advanced not more than one row of , trees. Each infected tree forms a center of infection so that spots of measled trees were found throughout that. part of the orchard where the Delicious trees were planted. Infected trees are stunted, branches die back ,in severe cases and in the course of a few ycars: the trees become worthless. The symptoms do not appear during the growing season but they manifest themsclves in the iate fall and winter. Apparently severe pruning of infectcd wood checks the disease. According to Crawford (New Mexico), "Measles occur all over the state where. Jonathan are grown..- Most severe on alkaline soil.
Mosaic (chlorosis) - was reported on Baldwins in New York.
Rosette (non-par.) = Idaho.
A new discase resembling scald was observed in packing houses in several of the Northwestern apple districts during the past scason. Apparently this trouble was found only on apples which had remained for sometime unwrapped in contact with some of the vencered tops and-bottoms which were introduced for use in making apple boxes this season. Only that portion of the surface of the apple which had apparently been in contact with the wood was affected?
Leroy Childs, Superintendent of the Hood River Experiment Station, states that he and Gordon G. Brown, Station Horticulturist, are making observations concerning this new apple affliction. They have accumulated a number of com-— mon woods employed for box-making purposes, and have placed apples thereon to determine the effect. Owing to the fact that much confusion exists among lumbermen, relative to the succific names of the various woods involved, thev have sent samples of all the wood received to Stanford University, for the pur- pose of getting a determination of each species of wood tested, so that they may accurately determine such woods _as may cause injury. Mr. Childs states that they have obtained injury on wood that has been called Yellow Fir, Oregon Pine, and a material just labelled Fir, all. of which he believes are Douglas for =(hepu,ye. G. In U. S. Dept. Agr. Bur. Agrs Beon. Fruit. & Veg. Diy. letter 6: 138. Mar. 27, 1925.) |
Internal breakdown (non-par.) - Minnesota, VYashington, and Idaho. In Idaho, according to Hungerford, it was especially bad on Rome Beauty, Winesap, anc Jonathan.
Spot necrosis (non-par.) -— reported fron three counties-in ied: Incompatibility of black walnut* and apple trees — Schneiderhan (36) of Virginia reported the death of apple trees in the proximity of a black wal- nut trees The area of toxicity coincided with the area of development of black walnut roots.
Winter injury -— Oklahoma, Bee yet and Oregon. According to Barss of Oregon it was important this year, being severe in the Willamette and Hood River Valleys, and worse on old than on young trees in the latter section.
224 APPLE -— Other diseases
Spray injury — New Jersey, Washington, Connecticut, Delaware, Indiana, and Virginia. In New Jersey severe leaf injury followed the use of A—5-50 Bordeaux. In another orchard where sulfur—lead—lime dust was used there was a severe burning of the center or the*tear. “In the: orehards sprayed with dry—mix sulfur—lime, brown circular areas resembling frog-eye were observed. In Indiana Bordeaux oaused russet on Ben Davis, sulfur sunburn was noted on Rome and iinnard and sulfur dust injury occurred in the experimental orchard at Lafayette.
In Virginia Schneiderhan-(36) reported experiments on the results of us- ing lime-sulfur alone and in combination with lead arsenate and calcium casei- nate; Bordeaux mixture 3-450; lead arsenate; copper hydrate; and dry-mix sul- fur lime. Spraying these materials at a temperature of 51° F., resulted in se- vere russeting: by Bordeaux mixture and copper hydrate but no injury from the other materials. However, applying at 94° F. resulted in severe injury from the lime-sulfur combinations and no injury from Bordeaux, copper hydrate, lead arsenate and dry-mix. The maximum injury following Bordeaux occurred 20 days after application, while the maximum injury following lime-sulfur was noted five days after. The use of calcium caseinatein combination with lime- sulfur and lead-~arsenate reduced spray injury 20 per cent.
Drouth injury - reported from five states. In a certain part of Texas, according to Taubenhaus, it caused a loss of 50 per cent. In Arkansas, many trees were killed or weakened by dry weather according to Young.
Sunscald (non-par.) — Delaware, New York, Arkansas. According to Adams of Delaware, "Sunscald became very prevalent on fruit the first week in June. Karly Ripe, Transparent, Dutchess, and York Imperial showed greater injury than ‘previously observed."
Disease surveys
! The eae apple disease survey pibedt ca this year was by Hurt of Virginia, (table 57)- Table 57. Apple diseases and other injuries found on Pippin, Winesap, York, Stayman, and Ben Davis in 42 orchards, Crozet, Vir-
Bite. a2 ys.
:Per cent infected:Maximum percentage: Average percentage
Disease = orchards : Of Inteckron : of infection Scab : 25.0 : 25.0 - 015 Cedar rust : ape ele : : 215 : trace Bitter rot 9.4 1A. gi trace Blotch : 6.2 : 2,0 pits 09
yo Biagle rot, ° : Belge 1.0 : | «2 - Flyspeck : trace Po es ae iN trace Russet : Ge : CP 4 2 059 Sooty blotch : 652" : trace : trace Pireblight - O° : O : 6) Bitter pit Shae bo) ie eae 02 Water core Bebe 8) : Oeis isis 0
Spray burn : 375 : Ah wt : 58
225 APPLE - Miscellancous literature
Recent literature on miscellancous apple diseases, apple spraying, etc.
1.
14.
15.
Anon. Apple transport problems. Investigations by a scientific ex-. pedition from the food investigation board. South Africa Fruit Grow. 12: 269-271. Aug. 1925. ons main
Anon. Experiments on keeping apples in oiled wrappers. Jour. Min. Agr. Great Britain 32: 626- 629. Oct. 1925.
Anon. Tratamiento eficaz para combatir la 'fumagina't de la Manzana 'Cara Suciat. (Control of flyspeck of the ‘Cara Sucia! apple Min. Agr. Nac. (Buenos Aires) Secc. Prop. e-Inform. Circ. A468: 3-7, 1925.
Baker, C. E. How oiled Wraps prevent scald on apples. Better
Frit 20,( 20). 31-12. fu 1925.
Bhosalé, Yn P. . iow temperature and root injury of the apple. Amer.
Fruit Grower 45 (4): 12. 1925.
Birmingham, W. A. An uncommon watercore condition in apples. Agr. Gaz. New South Wales 36: 59-62. Jan. 1925.
Blake, M. A. Apples are injured by severe drought. Marked differ- ence in varietal resistance. New Jersey State Hort. Soc. News 6: 132. Nov. 1925.
Briton-—Jones, H. R.- On the diseases known as 'bark canker' and die back' in fruit trees. Jour. Pomol. & Hort.-Science 4: 162-183. fae
Brooks, F. T. Polyporus adustus (Willd.) Fr. as a wound parasite of apple trees. Trans. British Mycol. Soc. 10: 225-226. 192%.
Brown, BE. Apple leaf scorch. Gard. Chron. III, 77: 440. June 1925.
Brown, We. <A study of forms of Fusarium occurring on. the apple fruit. Rep. Proc. Imp. Bot. Conf. London 1924: 339-346. 1925.
Carne, W. M. Cracking and russeting of Dunn's and other apples. doure Dept. Agr. Western Australia IT, 2:.214. June 1925.
Carrick, D. B., and J. Qskamp. Storage scald of apples. Cornell Univ. Coll. der. Ext. Serv. Bul. 128: 1-10. Sept. 1925.
Dillon Weston, W. A..R.e A a sey note on the perithecia of Nectria galligena. Ann. Appl. Biol. 12: 398. 1925.
‘Doran, W. L.. Experiments on the control of apple-scab and black rot
and spray:‘injury in 1924. Massachusetts Agr. Exp. Sta. Bul. 222: 10 pp» unnumbered. 1925.
226
16.
ry:
226
az
41.
APPLE - Miscellaneous Literature
Durham, H.. He ‘Apple leaf scorch....Gard. Chron. -III, 7/% 3'72-373- May 30, 1925.
- Apple leaf scorch. Gard. Chron. ITT, 78: 44. July es oe ANS 2sg oe ; ae a ae ‘
Eriksson, J. Phytopathologische Mitteilungen I. Ark. Bote 19 (6): 1-29. Apr. 1925. - Fusarium wilkommi.
Fenner, HE. Aline. A rot of apples caused by Botryosphaeria ribis. Pike gS F aT aeas ag
mace, H. Le The new spray materials. Canad. Hort. 48: 27-28; 46-48. Feb. 1925.
Hatton, R. G., and N. H. Grubb. Field observations on the incidence of leaf scorch upon the appies- Jour. Pomol. & Hort. Sci. 4: 65-~ (+. dane I92¥ pe Ms, } ee hax
ledrick, U. P. Winter injury of fruit trees. Amer. Fruit Grow. Mag. 45 (4): 3, 39+ Apr. 1925. ee 7
Hooker, H. D. Cages hydroxide as a sites Minute for bordeaux. Proc. Amer. Soc. Hort. Sci. 21: V5 176. 1925.
Horne, A. S. Fungal diseases of stored apples. Rep. Proc. Imp.
Bot. Conf. London 1924: 363-372. 1925.
E. -Crown- or-collar rot. Syatui: Advocate 60: 5543. Apr.
Kidd, M- N., and A. Beaumont. An experimental study of the fungal invasion mie in storage with particular reference to in- vasion through the lenticels. Mem. Food Invest. Bd. Great Britain 60; 14A-33+ 1925. Reprinted from Ann. Appl. Biol. Feb. 1925.
Lang, J. H. The development of "scald" in cold stored apples. Fruit World Australasia 26: 62-63. Feb. -1925-.
McClelland, N., and Le W. Tiller. Flesh collapse in apples, season sleip Influence of variety, maturity and. cold storage conditions. Pruit World Australasia 26: eer, a2. July 1, 1925.
gees, W. J-, and D. Folsom. Apple spraying and dusting experiments 1918 to 1924. Maine Agr Exp. Sta. Bul. 325: 126-184. July 1925.
Motz, F. A., FP. J. Schneiderhan, and W. J. Schoene. Spray infor- mation for Virginia fruit growers. Virginia Agr. & Mech. Coll. & Poly. Inst. Ext. Div. Bul. 94: 1-21. Jan. 1925.
Potter, G. F. Winter injury to apple roots. Fruit Belt a (11): Se 25. Nov a 192 he :
Se
38.
39°
Shear, C- I-, Ne Bs Stevens, and Me°S. Wilcox. Botryo eore
APPLE —~ Miscellaneous Literature
Ramsey, G. B., and L. F. Butler. Ammonia injury of fruits and vegetables in ey ae (Abstract) Phytopath. 16: 74. Jan.
2
Rhoads, A. S. Apple measles. Amer. Fruit Grow. Mag. AH (1): li-12. Jan. 1925.
Rose, D. H., and C. C. Lindegren. Phytophthora rot of pears and apples. Jour. Agr. Res. 40: A63~-468 . Mars Le ig25~
Ruth, W. Ae Prevention of apple scald with oiled papers. Transe Illinois State Hort. Soc. 58 (1924): 229-232. 1925.
Schneiderhan, F. J. (Osea disease studies in northern Virginia. Virginia Agr. Exp. Sta. Bul. 245: 1-45- Feb. 1926.
aeria and Physalospora in the eastern United States. Mycologia 1’: clom 107. May-June 1925.
Smith, A. J. Brown heart in Australian apple shipments. Spec. Rep. oe Invest. Bd. Great Britain 22: 25 ppe 1925.
smith, H. V. Cold oe experiments. Oiled wrappers prevent scaid in Granny Smith apples at Batlow, New South Wales. Fruit World Australasia 26: 107. Mar. 1925. at
Swartwout, H. G. Treatment of apple canker diseases. Missouri Agr. ta. Bul. 228 (Ann. Rept. Divector 1923-24): 59. 1925. |
owingle, C. F. Stem—borne rudimentary roots of apple — frequently confused with crowngall. U.S. Dept. Agr. Off. Rec. A (30); 5. dey 294.1925,
Burr-knot of apple trees -— its relation to crowngall : . 8 r eee % and to vegetative propagation. Jour. Heredity lo: 412-420. 1925.
Thomas, H. Ee Root and crown rot of apple. Proc. New York State Hort. Soc. 70: 171. 1925. oye
Thomas, P. H. Re-grafting apple trees. . The fungus disease Poly- sti¢tus verSicolor is often-troublesome. Some helpful sugges= tions. Fruit World Australasia 26:66. Feb. 1925.
Togashi, Ke ‘Some’ studies on a Japanese apple canker and its causal fungus; Valsa mali. Jour. Coll. Agr. Hokkaido Imp. Univ. Sap-
pore, Japa te: 265-324. Dec. ain
Cc n v
Van Poeteren, N. Verslag over de Psu acedibeaien van den Planten- ziektenkundigen Dienst in het jarr 1924. (Report of the activi- ties of the Phytopathological Service in the year 192A). Versi. en Meded Plantenzicktenkundigen Dienst de Wageningen Al: 62. 1925.
2238
APPLS ~—-Miscellaneous Literature PEAR — Blight
tar apple trees at Bengen were defoliated by a leafspot which bore immature fruiting bodies resembling pycnidia of Phyllos— ticta mali.
A7. Wallace, T. Apple leaf scorch. Gard. Chron. IIT, 62: 455-456.
48. Whetzel, H. H. The future of dusting. Trans. Penin. Hort. Soc. 360 (1924): 26-33. 1925.
A9. Young, H. C., and R. C. Walton. Spray in 15: 405-415. July 1925.
hO. Zeller, S. M., and Le. R. Childs. Perennial canker of apple trees. (A preliminary report.) Oregon Agr. Exp. Sta. Bul. 217: 1-17. Aug. 1925.
reduction of pears in the United States in 1925 was 19,820,000
The total p ared to 18,868,000 bushels in 1924. The total value of the 1925 0
bushels comp:
ee are = P B ‘a
crop was $27,944,000.00 while that of 192A was §26,693,000.00. In order of
their production, the states ranked as follows in 1925; California, New York, is
Washington, Oregon, and New Jersey. The state of California produced more than ears as any other state.
BLIGHT CAUSED BY BACILLUS AMYLOVORUS (BURR.) TREV.
Blight is co-extensive with pear culture and for a long period of years it has been the most serious disease of this fruit in the United States. Weather comitions in 1925 appear to have been particularly favorable for development and spread of the causal organism on apples and pears. Blight was corisiderably more prevalent in 1925 than in 1924. Of the 26 states reporting, the disease was more prevalent in 11, the same in 10, and less in 5 states. Those report— ing more were New York, Delaware, Alabama, Indiana, Illinois, Wisconsin, Iowa, Nebraska, Kansas, Oregon, and California. Compared to normal prevalence, states reported more, 6 less, and 7 the same. The 8 states reporting more than normal prevalence were Alabama, Illinois, Wisconsin, Kansas, Oregon, California, and Kentucky.
The following figures indicate such losses as were reported by the var-— ious states:
we ea ee
— se e.hlUh CCU Cll ee
224 sifgien ta - ‘Blight
Table 58. Hatinerted teeden from pear blight as din aat kg by collaborators,
qd 256 ‘Percentage: States reporting ::Percentage: States reporting OS ae 7 °:.-.: Loss =) : Georgia, Alabama | Bie A ; Kansas 20 : New York . Se 5 : Ohio: 18 : North Carolina a 2 : Texas 16 : California oH ie) 2 Delaware 15° =: Kentucky 2: ut : Virginia ~ 10 : South Carolina, Iowa, :: +) $: Connecticut : Michigan; I}linois as trace : West Virginia, Maine, 8 : Maryland su : New Jersey, Wisconsin, Bis ikea: Idaho
April 24 Urbana Tliinois June A New Brunswick New Jersey
April 25 Raleigh -- ° North Carolina June 10°. Seaford Delarare
May 1 Portsmouth Virginia July 10 Seabrook Néw Hampshire May 8 Lincoln | | Nebraska July 24 Hadlyme Connecticut May 19 Clemson College South Carolina August. 19 Milwaukee Wisconsin
May 21 Ulster County New York We have the following reports from collaborators:
New York (Ontario County): Fireblight has taken an exceptionally heavy toll this year, wiping out quite a few pear orchards. (Burrell) (Yates County) - Mixed pear orchard including the Seackel pear practically ruined for this year. (Raymond)
Delaware: First observed June 10. Has developed more rapidly and gen- eral distribution is greater than on apples Slight increase over last year. (Adams )
Georgia: Vigorous blossom and shoot blight in the spring. Only slow development after first week in April due to drouth of April and May. Renewed activity beginning the tenth of June in twig blight and canker forms. Fruit rot common but: not. severe. (Boyd)
Mississippi: Scrious blossom blight in many localities; 15 and 20 per cent loss. (Neal)
Oklahoma: Not so destructive as last year on the pear. Quite plentiful “on some varieties of doa (Rol fs)
\
Ohio: Very destructive iit onth outs Ohio this. year. _ (Young)
Missouri: Particularly severe this past season. (Bregger) |
ce ode PEAR - Blight
Nebraska: Much more prevalent and serious than last year. (Peltier)
Kansas: Unusually severe as blossom and twig blight this spring. Num- erous reports from all over the state, especially the northeast— ern section and Arkansas Valtey section, reported the disease as being present in-practically 100 per cent of the.orchards, es— pecially the older ones where it was doing its Worst damage.
This year's crop was Mecidedly reduced due to blossom blight and next year!s crop is handicapped already due to twig and spur blight. (White) :
Washington: Excessive damage along the Snake and in the Yakima Valleys. It has been prevalent in the Walla Walla section on apples and pears -but doing most damage to the latter. (Dept. Plant Path. )
Oregon: . In the Milton-Freewater district practically all trees were af- fected according to R. F. Wilbur, fruit inspector.. In Jackson County it has been. reported more severe than for several years peor heavy loss. Of no conseguence in the Hood River Valley.
Barss | ;
California:. Disease so bad in some regions that thrifty eight-year oid orchards were almost ruined. Some orchards didn't produce a crope Disease occurred in foot-hill sections where it is not of usual occurrence. (Milbrath)
The important work of Nixon (2) showing transformation and migration of Bacillus amylovorus in the holdover cankers has already been mentioned under apple.
‘In California, according to Heppner (1), the demam for Japanese pear stocks has decreased considerably in favor of French stock. The change is traceable directly to pear blight.
According to Waite (3):
"Pear blight occasionally attacks the fruit of summer. apples up to maturity but has never been found on mature winter apples or pears at harvest time or during winter storage, and under ordinary inocula- tion conditions the organism will not attack such fruit. The author shows, however, that under damp chamber conditions Bacillus amylovorus can attack the tissues of mature, winter apples, and also rose cuttings. Roses have never been found attacked by pear blight out of doors." ACP WS Ro BOLL) Abstr.)
Recent literature on pear blight (see also apple blight)
le Heppner, M. Je Recent root stock developments. -Amer. Fruit Grow. AH (4): 10, 50. 1925.
em Mixeny “Tels Migration and transformation of Bacillus any Lovorus in apple tissue. Phytopath. 16: 77- 1926.
3% Waite, M. B. pdare es infection of rose cuttings and of mature re fruit. Official Rec. U. 5s Dept. Agr. A: ps. 5. Aug. 192%
a
NO CN f4!
PEAR - Scab SCAB CAUSED BY VENTURIA PYRINA ADERH.
» Compared with normal, and 19 eu. prevalence, pear scab was less important in 1925. Thirteen states reported it and among them, 4 reported more than’in 1924, 6 less, and 4 the same. Those reporting more were New York, Oregon, California, and New Jersey. Only nine collaborators compared the 1925 preva- lence with normal. Of these, one state, Oregon, reported more than normal, 5 less, and 4 the same.
It is quite apparent that the heaviest losses in the country occurred in California, Michigan, and Oregon.
Table 59. Estimated losses from pear scab as reported by collaborators,
1925. Percentage: States reporting ::Percentage: States reporting. - Loss : era 23 oss 2 4 : California ae 5 : New Jersey @ : Michigan 2% trace +: New York, Virginia, 1.5 : Connecticut ge : Maine, West Vir- aL. : Maryland, Alabama, :: : ginia, Georgia, Wis— Oregon, Ohio 23) : consin, [owa, Kentucky
Dates and location of earliest reported appearance of scab, 1925
May A Dover. Delaware July 24 Essex Connecticut May 15 Winchester ( VERSUS. August 19 Milwaukee Wisconsin June 29 Genesee County New York “August 23 Middlesex New Jersey
Delaware: Very slight infection this year. (Adams) New York: Considerable on Flomish Beauty. (Chupp & Pierstorf#)
Virginia: Only one case noted at Winchester on Seckel pears, May 15. (Schneiderhan)
Sr Bn: There has been very little scab present. Susceptible varie- ties even when unsprayed showed very small amount. (Bennett)
Oregon: Worse than it has been for several years due to prolonged spring rains and cool weather. (Barss)
Lane County, - Very prevalent on most varicties. Loss on Bartletts 10 to 15 per cents other varieties 15 to 20 per cent. In unsprayed orchards the losses are, yy Ce 80 per cent. (Stewart)
232
PEAR — Loafblight ; Leafspot; Winter injury
LEAPBLIGHT CAUSED BY FABRAEA MACULATA (LEV.) ATK.
This discase has been- particularly destructive in New Jersey, Delaware, and Maryland. It is known to occur wherever pears are grown, but in recent years the most serious losses have been reported from the Middle &tlantic States. This disease also was less prevalent in 1925 than normally or in 192A. No state reported greater prevalence of this disease than for normal, three states reported less, and Maryland, in which the disease seems to be particularly Severe, reported the same. Leafblight appeared on May 14 in Taine Ps May 10 in Virginia, and July 7 in New Jersey.
Massachusetts: A serious case of this disease on nursery stock was noted in Amherst. (Osmuin & Davis)
Delaware: Where copper sprays were used only a trace of infection was found. Neglected trees ae defoliation on Jaky 275 but much
less than last year. (Adams)
Florida: Common over the northern section of the state. (Rhoades)
LEAFSPOT CAUSED BY MYCOSPHAERELLA SENTINA (FR.) SCHROET.
The reports on this disease indicate that it was less important- this year than usual. From the standpoint of economic importance it ranks as a minor disease. Jn Virginia it is the commonest disease of pears, but the loss occasioned: by it there is minor because pears are not grown extensively.
New York; Serious on neglected trees. (Chupp & Pierstorff)
Virginia: The commonest leaf disease of pears but of no great economic importance. (Schneiderhan]
Georgia: Less prevalent than last year. Probably due to drouth in April and May. Sale
Michigan: Present in nearly all orchards but of no economic importance. (Bemett) WINTER INJURY Winter injury seems to have been particularly severe during the winter of 1924 and 1925.
Alabama: Considerable injury caused by trees going into dormancy in poor condition. (Miles & Blain)
24%
PEAR -— Winter injury; European canker; Blackrot
fllinois: Pears nearly all killed by low winter temperatures December 26, 27, and 28, 192A. (Anderson & Tehon)
Michigan: In some orchards more than 50 per cent of the fruit will show some form of frost marking. (Bennett)
Minnesota: Pears grown on fruit breeding farm severely injured during the winter, Several trees killed. (Dept. Plant Path.)
Idaho: Severe freeze of December 1924 caused very large amount of injury. (Hungerford) aan
EUROPEAN CANKER CAUSED BY NECTRIA GALLIGENA BRES.
European canker was reported from Washington and Oregon. In the latter state it was said to be very important more severe than usual. It occurred in western Oregon including the Hood River Valley. Concerning the disease S. M. Zeller, of Oregon writes as follows: ;
; !
"Always more serious in seasons following extreme cold, as in 1920 and this year. Thin-barked more susceptible than thick-barked varieties. According to prevalence observed Surprise, D'Anjou, Bosc, Howell, Bartlett most susceptible in order named. Few cases on Winter Nelis and Comice.
In one orchard at Corvallis, in 96 trees of Oreille 81/3 per cent had trunks cankered, while of 408 trees of Surprise 445 per cent had cankered trunks.
"In 1922 a 3-year old orchard of 140 acres of Surprise near Grants Pass had 42 per cent of the trunks cankered. The disease was cut out according to the following recommendations and has not returned since.
"Control - 1. Where infection extends into the cambium it is cleaned ous thoroughly.
"2. Cases of superficial canker are merely scarified.
"2. All cleaned wounds are .coated with Bordeaux paste made up in raw linseed oil, using Sherwin-Williams “Fungi-Dordo" dust, stirring the oil into Until a thick paint is formed.
"A. Spray with Bordcaux 4-A-50 before first fall rains, and after leaf fall if possible (a large number of infections take place through fresh leaf sears), to prevent new infections. It is very important to spray before the fall rains." |
Recent literature 1. Dillon Weston, W. A. R.- A preliminary note on the perithecia of
Nectria galligena. Ann. Appl. Biol. 12: 398-400. July 1925.
BLACKROT CAUSED BY PHYSALOSPORA MALORUM
No unusual reports of this disease occurred in 1925. The same general prevalence as in previous years was reported. Maryland reported 5 per cent ioss.
23h
PEAR ~— Miscellaneous Diseases; Litereture .
MISCELLANEOUS DISEASES AND INJURIES
Black end (non-par.), Washington, California. From'the latter state W. fT. Horne reports the- trouble increasing and rather widely distributed. It occurs largely on individual trees scattcred through the orchards. According to Horne it seems to be worse on trees of Japanese stoek in situations with fluctuating water conditions. Milbrath estimates 0.5 per cent loss in Califor- nia on account of it. In Washington it was reported several times from the Yakima Valley.
Cercospora minima Tr. & Earle, leafspot, noted on sand: pear at Gaines- Wade, Florida.
Chlorosis due to excess of lime, Texas.
orticium stevensii (Noack) Burt,» hypochnose, Florida (defoliates trees
and kills back the young limbs).
Gloeodes pomigena (Schw.) Colby (Phyllachora po migona (Schw.) Sacc.) sooty blotch, Connecticut, New York.
ee perennans Zcller & Childs, perennial canker, Oregon.
Gymnosporangium blasdalcanum (Dict. & Holw.) Kern, incense cedar rust, Oregon. "Not important, occurs in western Oregon, especially in Lano County, but is not a factor in the crop as a whole." (Barss)
Hendersonia foliorum Fekl., leafspot, Florida.
Qzonium ommivorum Shear, rootrot, Oklahoma, Texas.
Red leaf (non-par.), New York, ay common on Kicffers.
Ring canker (undct.), California. |
Septobasidium eri Posie (Berk. & Curt.) Pat., Lidierd aici? Texas. . (Reported as Thelephora retiformis). :
Recent literature on pear diseases
l. Hartman, Henry. The control of core break-down :in pears. Oregon Agr. Exp. Sta. Bul. 216: 1-16. 1925.
a= Hendrickson, Ao He A pelea condition of pear trees. Proc. Amer. Soc. Hort. Sci. 21: 87-90. 1925. Also Blue Anchor 2: 6, 25-26. Nov. 1925.
3. Lipman, C. B., and A. Gordon. Further studies on new methods in the physiology and pathology of plants. Jour. Gen. Physiol. 7: 615- 623. 1925. Chemical injections. sake .
A. Milad, Y. The distribution of iron in eles pear trees. Proc. fimer., Soe. Hort. sei. 2ls 93-98. Ser 25 5
5. Ramsey, G. B.,and L. F. Butler. Ammonia injury of fruits and vege- tables. (Abstract) Phytopath. 16: 73- Jan. 1926.
6. Rose, D. H., and C. C. Lindegren. Phytophthora rot of pears and apples. Jour. Agr. Res. 40: A63-A68. Mars 1, 2925«
a se
235 PEAR ~ Miscellaneous Litcrature QUINCE - Leafblight; Blight; Rust
{> Van Poeteren, Ne Versilag over dc Werkzaamheden van den Planternziek- tenkundigen Dienst in het jaar 1924. (Report of the activitics of the, Phytopathological Service in the year 1924.) Versl. en Meded. Plantenzicktenkundigen Dienst te Wageningen 41; 62 jer 1925<
QUINCE ©
: { LEAFBLIGHT CAUSED BY FABRABA MACULATA (LEV.) ATK.
Only six states réported on this disease. It was reported to be impor- tant in Connecticut where it occurred in greater prevalence than normally, and in New York the loss was estimated at 1 to 5 per cent. Defoliation followed a Severe attack in certain parts of New York and Delaware.
Dates and location of earliest reported appearance of leafblight, 1925
Borat 14 Clemson College South Carolina July 20 Monroe County. New York July Seaford Delaware _ July 22 Wellingford Connecticut
BLIGHT CAUSED- BY BACILLUS AMYLOVORUS (BURR.) TREV.
Ten states reported on fireblight of quince. It is noteworthy that this organism affected quinces only slightly in 1925, while, as we have seen, it Was the only disease of apples and pears which showed greater prevalence than normally. Only Massachusetts reported more blight on quince than in 1924. In that state, according to Davis, it was more prevalent on quince than on pear Or apple. The only considerable losses reported were 10 per cent from Maryland and 4 to 5 per cent from New York.
Dates and location of earliest reported appearance of blight, 1925
May 20 Amherst Massachusetts June 14 Middlesex County New Jersey June 11 Georgetown Delaware June 22 LaPorte Indiana
RUST CAUSED BY GYMNOSPORANGIUM GERMINALE (SCHW.) KERN
Quince rust was reported from six states, New Hampshire, Massachusetts, Connecticut, Maryland, Virginia, West Virginia, and Alabamae Maryland and Virginia reported normal amounts, while New Hampshire reported more than nor- mal prevalence.
236 , QUINCE - Rust; Miscellancous ‘Diseases; Literature. PEACH» — Brownrot
Dates and location of carlicst reported appearance of rust, 192 we:
June 10 Durham New Hampshire June 19 Strasburg Virginia August 1 Saybrook Connecticut
MISCELLANEOUS DISHASES AND INJURIES
Frost - Maryland (2 per cent loss). Michigan, fruit reduced to the ex- bent of AQ per cent.
Glomerella, cingulata (Ston.).Spauld. & Schrenk, bitter rot, Connecticut.
Aerial galls, according to McClintock (1) aerial galls on quince are not crowngall but are Similar to the “burr knots" described by Swingle (2) on apple and pear.
Recent literature gees ; ls McClintock, J. A. Acrial galls of quince. (Abstract) Phytopath. 16: 73.4 Jan. 1925. :
2. SWingle, C. F. Burr-—knots of apple trees - its relation to crowngall and to vegetative propagation. Jour. Heredity 16: 412-4205 Ie Se
DISHASES- OF STONE FRUITS
The total peach production in 1925 was estimated to be Ab, 565,000 bushels compared with ra 119,000 bushels for 192A. The total value of the peach crop in 1925 was $65,0 i 000. OO compared with $65,679,000.00 in 1924. In the order of production in 1925, the states ranked as follows, California, Georgia, Arkansas, New York, and Texas. .The state of California oe as more than twice as many peaches as any other state.
Drouth and frost injury were very largely instrumental in reducing peach production in such states as Georgia, Virginia, Maryland, and West Virginia.
Fungous and bacterial diseases and other injuries of peaches were consid— erably less prevalent in 1925 than the year previous and normally. The total money loss due to diseases was very much less this year not only because of a lower average prevalence but also because the crop was comparatively small.
BROWNROT CAUSED BY SCLEROTINIA FRUCTICOLA (WINT.) REHM (S. AMERICANA (WORMAID) NORTON & EZEKIEL) ;
Brownrot of peaches was considerably less prevalent this year than in 1924 and normally. Only two states, Connecticut and New York, reported more
237 PEACH -— Brownrot
than in 1924. Of the other states, eight reported less, and six the same preva- lence as in 1924. Two states, New Jersey and Delaware, reported more than nor- mal prevalence, eight reported less, and five the same. We infer; therefore, that brownrot was of less importance this year than usually due, as mentioned in a number of reports, to dry weather.
Table 60. Estimated losses from brownrot as reported by collaborators, tS iaore .
Percentage: Otates reporting ::Percentage: States reporting
loss : 28 Loss
HO : South Carolina mr Teac New vondls
7 : Maryland Beenie : Virginia, Ohio
5 : Arkansas, North Caro- ar Taal ’ Delaware, Indiana, Kan-
; line, Michigan | ™ ae > sas, Alabama, Texas A. : New Jersey, Connecticut :: : -5: .:. Georgia D
Kentucky, New Mexico 28 trace : West Virginia, Illinois
California, which produces by far the largest crop of peaches in the United States, did not report any loss from brownrot.
As in previous years, this disease manifested itself chiefly in the form of twig blight and fruit rot. The first mentioned form was considerably less important this year than usual due to dry weather at the time of blooming.
Dates and location of earliest reported appearance of brownrot, 1925
February 17 Frogmore South Carolina June 2 Waite Co. North Caroli Aprad "25 Burlington Coe New Jersey June 5 Dover Delaware May 15 Fort Valley Georgia July 28 Weatherfield Connecticut
June 1 Divtehess Co. New York Sept. 10 Leesburg Virginia
New Jersey: Severe blossom blight in some orchards. Heavy losses from fruit rot in others. (Martin)
Virginia: An unusually severe infection by brownrot was noted at Lees- burg on Bilyeu variety. In spite of the fact that one block of these peaches was sprayed eight times with dry-mix and the other block was sprayed five times with dry-mix and then dusted with sulfur dust on August 25, September 17 and 24, the crop in this orchard was practically a total loss. Fruit infection to the ex- tent of 45 per cent appeared before fruit was ripe. The drops in these blocks showed 100 per cent infection. A conservative esti- mate of total fruit infection ia 80 per cent. This orchard was
“very severely infested in 1924 and unless the disease is checked by a pre-—blossom spray and severe pruning, this mtire block of trees will have to be destroyed because it is acting as the center of infection to the other peaches in the orchard, which is the largest in Virginia. (Schneiderhan)
Georgia (Fort Valley): Not commercially important due to dry weather throughout the growing season. Apothecia were first observed in orchards March 2. This date is probably four to six days late as
238 ey
‘PEACH ~ -Brownrot
some of the apothooia } Oa ee up. -No apothecia found
after March 14. Blossom-blight.with the accompanying twig ca ankers |
did not attain any commercial importanec even:on the very suSCCD—_ tible varictics such as Uneeda and Mayflower. - The. Summer con-_. tinued hot and dry, but on October 23, following a short period
of rainy weather, aburdant rot was noted. on fruit.in small orchards
of late Boagies (Dunegan) Florida: Glscieagt on ee fruit generally: ‘in the-northern part of the? state. (Rhoads)...
Seema a ee eee fees
Ohio: Causing quite considerable losses in home orchards. Very Little of the disease is noted in commercial orchards. (Young)
Indiana: A scrious eubbyons peared ina PR Cee seciehes: si 8 of Krum- mels in Knox County -in Scptember.’: This orchard. had been thor- oughly sprayed and the difficulty is attributed to the high per- centage of .growth. cracks that occurred as a result of the Sept- ember reins. (Gardner) NOMI Woks)
Oregon: Of some impor tance © in tho Willamette ee especis abil on Late paplkee eRe
According to the report of the Chief of the Bureau of Plant Industry ..(5) for the year ending June 30, 1925, the application of sulfur dust two or three weeks before picking. time in Gcorgia hrs reduced the development of-brownrot on peaches in transit in cases where rains were comaon curing the picking sea son; ” but in drier weather, this dusting has been unneecssary and of little value. A delay of a few hours in cooling peaches makes a decided difference in the char- acter and amount of the rots that develop, Jater..an Crensihy Brownrot spores lodged in cuts and bruises on the peach develop even at a a temperature of AL” ie but spores on the surface of the peach seldom develop rot at this temperature. At A3° F - and higher spores dusted on the Seni caused a fairly .rapid develop- ment of rot without the aid of cuts and bruises in the skin. . Dusting peaches by the use of OU gay appears to be promising in Gcorgia.
Barss (1) has reported that much loss is experienced annually. in orchards of the Pacific Northwest: from western British Columbia to western ‘Oregon and perhaps farther south, from blighting of blossoms and killing of spurs, ard sometimes cankering and girdling of twigs and smaller branches, followed by a negligible amount of fruit rot, caused by a species of Monilia differing from that ordinarily reported as "Selerotinia cinerea" to: which the name Monilia -oregonensis Barss & Posey has been given. . The principal hosts attacked are apricots, sour and swect cherrics, prunes, ‘peaches, and pears, and quince and epple fruit has been found infected. The:fungus winters in the blighted parts. Apothecia were not found, and were not acatinth under conditions favorable for their formtion in "Ss. cinerea." ;
Ezekiel (A) studic@ cultures of Me. oregonensls. eee from Barss, and also of a fungus isolated from decayed peaches, cherries, and apricots sent from California by B. A. Rudolph, and reported that "These were compared with a large population of other single-spore cultures, also collected in this country, and now all assigned to S. americana, and with §. cinerea and 8S. fructigena cultures from England and Holland. Of the California and-Oregon strains mentioned above, all except that on apricot were found to be trmue.S. cinerea." |
‘ ‘ ; : e ; f iy i
y
249 PEACH - Brownrot; Leafourl
Recent literature on brownrot
1. Barss, H. P. Serious blossom blight in Pacific Northwest orchards due to a species of Monilia. (Abstract) Phytopath. 15: 126. 139 Pag sth ae
es Brooks, Gay ard D. F. Fisher. TP saad for brownrot in the North— “West. Amor. ‘Fruit’ Grow. Mag. AD (6): 10, ay, 5h. sume 19255 Also Blue Anchor 2 (9): 18-19, 36-37. Sept. 1925.
4+ Ezckicl, W. Nw. Fruit-rotting Sclerotinias II. The American brownrot fungi. Maryland Agr. Exp. Sta. Bul. 271: 87-142. Oct. 1924.
A. Presence of the European brownrot fungus in Americas Phytopath- 15: 535-542. 1925.
h» Ho esc lieis C. Me Plant diseases of Alou dunes: Brownrot of stone fruits. New ees Agr. (3): by. Aug. 1925.
6. Muhloman, G. We The eee of Sclerotinia cinerea. Bot. Gaz. 30: 325-330. Nov. 1925.
{> Schneiderhan, F. G., and R. H. Hurt. The dry-mix spray for peaches. Virginia Agr. Exp. Sta. Bul. 239: 1-16. Jan. 1925.
8. Taylor, W. A. Report.of the Chief of the Pureau of Plant Industry 1925: 1-36. 1925. (Unnumbered report, U. S. Dept. Agr.)
IEAFCURL CAUSED BY EXOASCUS DEFORMANS (BERK.) FCKL..
Peach leafcurl is one of the best known and most widely distributed dis- eases of this fruit in the United States. The records show that there is no sharp geographical limitation to this disease, although certain states, particu- larly New York, Pennsylvania, Maryland, Michigan, and PE CER. have reported the greatest losses. The relation between cool, wet weather at the time of bud ex- pansion and infection is well-known. Nothing new has been contributed in ios to the knowledge of this discase, although an exccllent resumé of the whole sub- ject has been given by Coons (1).
In 1925 leafcurl was considerably less prevalent than in the previous year and normally. Only three states, Delaware, Kensas, and California, re- ported a greater prevalence than 1924, while ten states reported less, and six the same prevalence as last year. Comparing this ycar'ts prevalence with normal only two states, Delaware and Kansas, reported more, eleven states reported less, and five the same as normal.
Lossés resulting from peach leafcurl this year were not severe. The records of the past cight years indicate that crop losses to the extent of 20 per cent have been reported. This year the highest loss, 4 per cent, was re- ported from Kansas and Maryland. A number of reports, including those from Vassachusetts, New Jersey, Delaware, Maryland, Virginia, Oregon, and California, stated that the disease was abundant in unsprayed or poorly sprayed orchards, o:' where spray was applied late.
2A0
Table 61. Estimated losses from leafcurl as reported by collaborators, 1925. ! baie Ae Percentage: States reporting ::Percentage: States reporting TOSS. 2 gels loss | 4 : Maryland, Kansas =e trace : New York, West Virginia, a, : South Carolinas: Northen.) «© ..<.<¢,j)dhabeme, Liliness, : Carolina, Oregon a : Michigan, Maine, Ken- heh : Delaware, Texas © ai : tucky, Oklahoma, Ark- dig : New Mexico, Michigan :: ; ansas, Idaho . oF : New Jersey, Virginia,:: Be ails orn oe Ohio, California 3
= cf °
Dates and location of earliest reported appearance of leafcurl, 1925
fpret if). Crozet . a: Virginia May 6 Dutchess County New York April 14 Clemson College South Carolina May 15 Vineland New Jersey April om -~+- Delaware June 1 --- New Hampshire
April 24 Orange County Indi ana
: Some interesting and informative reports were: submitted by various col- laborators. Among them the following are noteworthy.
Delaware: Injury noted on leaf and shoot. Was general throughout the State. Delay in putting on dormant spray favored greater general increase over last year. (Adams)
illinois: No leafcurl wes observed in the peach growing section this year in sprayed orchards regardless wnether sprayed with oil-emul- SEOn or Lime—sulfur: (Anderson) a
Kansas: lLeafcurl is evidently more severe in the southeast part of the state than normally due to a very wet spring. ‘Some defoliation has been reported as due to leafcurl. In general a dormant spray of lime-sulfur has given’ satisfactory control. (White)
Washington: Present in both eastern and western Washington, but less abundant than’usual. Not in the central irrigated valleys. (Dept. Plants Path.) |
Oregon: General and serious wherever not controlled. Prolonged cool,wet spring. <A grower in the Willamette Valley reports "Very bad in most orchards as the spraying was delayed due to rainy weather at spray time." Can be controlled perfectly by winter spraying with Bordeaux. Elberta is the only commercial variety severely affected by leafcurl, but this variety is quite largely grown. (Barss)
Califomia: It appears now that fruit was affected. This was deformed. Growers sprayed too late on account of the rains. (Milbrath)
PEACH ~ leafcurl; Scab
Recent siterature on leafsurl
1. Coons, G. H. Old and new facts about peach lea&fcurl. “Amer. Fruit - — - = ne a 7 a 4 Fea Grow. 45 (2): 33, 46-47, 53. 1925.
2. Encke, F. von. Die Krauselkrankheit desrPf
n irsichs. Deut. Obst— u. Gemiiseb. Zeit. 71: 207-208. May 22, 1925.
4- Mix, A. J. .The weather and peach leafcurl in eastern Kansas in 192A.
Phytopath. 15: 244-245. 1925.
SCAB CAUSED BY CLADOSPORIUM CARPOPHILUM THUEM.
Pao
Scab appeared to be far less prevalent this year than usual, as indicated Dy the fact that only one state, Delaware, reported more of the disease than normal, while ten reported less, and two the same. The same figures are tru of the comparison between the 1925 prevaience and that of 1924 with the exce] tion that only Connecticut in addition to Delaware reported more scab.
scab is provably easier to control in average seasons than any other fungous disease of the peach. The regular spray programs applied in 19255 saded by weather corditions distinctly unfavorable to the development and spread of the fungus, especially in the southern and castern Appalachian section, resulted in avery low loss this year. The following table gives the losses reported.
a o
Table 02. Kstimted losses. from scab as reported by collaborators, 1925. Percentage: States reporting ::Percentage: States reporting loss : ~S loss : 2 : North Carolina a 275 ; Connecticut JPG : Maryland, Georgia ot 5) : Virgerea, New Jorsey 1 2 Siorida, sitesi ok trace’ ': New York, West Vir— » Delaware, Mississippi ss* e “Sina. Niekican, : Texas, lene eerice @uae & > Kansas \
eo. @ s e °
Dates and location of earliest reported appearance of scab, 1925
fpril 20 Burlington New Jersey July 2 Crozet - Virginia
April 24 Lawrence County Indiana wiiy. cc.” Cheras south Carolina Pere) Bridgeville Delaware fugust 1 Westville Connecticut June 17 Powersville Georgia August 10,Green County New York
A record of conidial development on cankered peach twigs at Crozet, Vir- ginia, kept by Hurt, table 6%, indicates that conidia are procuced over a com- paratively long period of time and after practically every rain.
PHACH -— Scab; Bactcrial spot
Table 6%. Data concerning peach scab conidial production, : Crozet, Virginia, 1925 (from R. H. Hurt).
: ¢) CRE dda
Date we Ol ar OC ue oa Onli (inches) May 24 : Light : Qe! June é : Medium : rey June 24 : Heavy : hue June 27/ : Heavy 4 0.0% July 6 : Heavy : 0.95 July 8 : Heavy : 0.60 July J : Medium : 0. 49 August 4 : Light : 0320 August 9 : Heavy : 0.75 August 10° 7; Light : 0.19 Augusity dy ous Heavy : 0.55 Avews st. desis Heavy : O.24 AGL ee Cee iight : O.11
ve eo
Delaware: Heavy twig infection. Slight increase on fruit. (Adams) Virginia: Unusually late in appearing. (Fromme) North Carolina: Rather prevalent despite the drouth. (Fant)
Georgia (Fort Valley): Due to dry weather, scab was not commercially important except in neglcctcd orchards. First evidence of dis- ease seen on May 4 on Blibertas. On June.17 the disease was found on unsprayed sccdlings near Powersville, Georgia. The spots on these fruits were fairly numerous. Later, July 8, it was found on commercial fruit at picking time in an orchard thag had not been properly cared for. Numerous cankers on the twigs were probably the source of the infection. Following the first rains in October after a long dry period, numerous scab spots de= veloped upon unsprayed foliage. he fungus was sporulating vigor- ously on the spots and cultures were readily obtained. Leaves bearing these spots could still be collected in the early part of November but at this time the spots were not as large nor as numerous although they wore sporulating freely. (Dunegan)
Ohio: Scab is ouite gencral throughout the central portion of the state, especially in unsprayed orchards. (Young)
,
my
BACTERIAL SPOT CAUSED BY BACTERIUM PRUNI EFS.
Compared to previous years, bacterial spot was very much less prevalent. Only two states, New York and Kansas, reported more shot-hole than in 192A, and only Kansas reported more than normal, while nine states reported less than nor- mal, and eleven less than 1924.
PHACH — Bactcrial spot
The losses in iges Were Nob great, the heavicst reported berg \F per cent in North Carolina.
The accompanying table 64, gives the.losscs reported from the various states.
Table 64. Estimated losses from bacterial spot as reported by eee
Percentage: States reporting ::Percentage: States reporting loss : oS loss : 5- : North Carolina Rika trace ; New Jersey, Maryland, J : flabame, Texas, Kan-:: : Virginia, Michigan, sy Sas, New York i : Fowa, Arizona a oni wogs aN :
. ° ee °
the states reporting losses, the Elberta and Hale varieties seem to have _ the most suscentible.
+
Datss and location of rlicst reported - marance cf bactoria lL spat,.I92
April. 29. Fort Véelley Georgia Junc 2@o Moore County North Carolina
May 7 Lawrence County Indiana June 2 range County Now York
May 14 Bridgoville Delaware July 22 McBee South Carolina
May 17 Winchester Virginia July 29° Bridgeton New Jersey
May 29 Ozark Lilinois
ew York: Reported as rather gencral but it is difficult to determine
how much was caused by this injury or by spraying. Heavy loss of foliage in a few orchards of Niagara County. (Chupp .& Picrstorfz)
ai air aG this time fencrally ilcss than last yeans)! Heavy twig infcction .found ony Epc FIPSst Gime on Biber ba May 28. ) oO 3
inspectors report damage to Hales and
North Carolina: Shippin a s high as 30 per cent in some instances. (Fant)
i Elbcrtas running
Georgia: Duc to dry scason, this discase is of minor importance in Fort Valley bolt. Initial infection could be attributed directly to bacteria overwintering on the twigs. First noted April 29. These spots on the fruit were smali and contained practically pure cul-— tures of the organism. No defoliation observed during the season. No twig cankers found on the 1925 wood. (Dunegan)
Oklahoma: Not picntiful as last year. Very little fruit injury by this organism during this season. Icaf infections more or less plenti-
ful in most orchards. (Rolfs)
Indiana: Too dry in April and May. (Gardner)
244
PEACH - Bacterial spot
Illinois; Bacterial shot—hole as late this season due to the dry weathes during the period when initial infection usually takes place. Defoliation in fertilized orchards was not as severe as in those not nitrated. Mainly on Elberta and Hale. Very little fruit infection and foliage inclined to hold better than usual. (Anderson & Tehon)
Kansas: Common and serious this year in Coffey County. Sixty-five to seventy-five per cent of twigs killed tack as much as half of last year's growth. (‘hite)
es - .
In 1925 an advance seems to have been made in the control of bacterial spot as a result of work done by Anderson (2) of Illinois. He reported as follows: | pied:
"Spraying ex ‘(periments on peach for control of bacterial snot (shot- hole) during 1925 at Urbana, Iliinois, demonstrated the vossibility of control with a spray of sodium silicofluoride in water. Preliminary laboratory tests proved this substance effective in preventing growth in broth cultures in dilutions of 1-4,C00. Seven appiications were made, ten to fourteen days apart. Various concentrations were used. One containing two pounds in 50 gallons of water proved satisfactory. The checks showed from 10 to 90 per cent diseased leaves on October 1, while very few in- feetions could be found on the sprayed trees. t is provable from the dates of infection that only three of the seven sprays would have been necessary for control. Suliur sprays first gave increased infection over the checks, due probadly to wetting the trees during spraying. Later the checks were more heavily infected. No injury to the foliage resulted from the use of the sodium silicofluoride, neither in the orchards nor in the greenhouse where preliminaryttssts were made. This season's weather condi- tions were so abnormal, howcver, that no assurance can be given that that injury wWiil not result in other seasons. Copper sprays, including two brands of colloidal copper and Pordsaux mixture, caused serious spray in- mury 2 "
The same author (3) also contributed the results of five years of inves- igation on the overwintering habits of Bacterium pruni under Tilinois condi- ons, indicating that the pathogeni¢ organism does not overwinter entirely in cankers on twigs as reported from other states but also on ieaves. No diffi- cuity was experienced in isolating the bacterium from leaves in the spring. The exact method of inoculation is not known but the author assumes that the bact-— crla occurring in the gelatinous masses are blown as dust to the grecn leaves and when moistened fqoe cause infection.
Recent literature on bacterial spot
1. Adams, J. F. The defoliation of peach trees in relation to spray materials and bacterial shct-nole. Trans. Penin. Hort. Soc. 38: i7-e2l. 1925. .
2. Anderson, H. W. Control of bacterial spot of peach with sodium silicofluoride. (Abstract) Phytopath. 16; 79-80. Jan. 1926.
; | ; ;
————— ee
245 PEACH ~ Bacterial spot; Blight; Yellows
4. Overwintering of Bacterium pruni- Phytopath. 16:
--55-57. Jan. 1926.
Meee Ue ie Shot-hole or bacterial spot of peach. Amer. Fruit Grow. Mag. 45 (2): 26, 38-39. 1925.
Some observations on bacterial shot—hole of peach. Trends. Pilot Ste te Port. SOC. 58: A88-497. LUG dare
oe ente, Ra hy.” Biaele spot or bacterial crack of the peach. Trans. Penin. Hort. Soc. 40: 15-16. LS NElaye
BLIGHT CAUSED BY CORYNEUM BETJERINCKII OUD.
Peach blight was reported from Ohio, Michigan, Colorado, Idaho, Washing— ton, Oregon, and California. California reported a crop reduction of 4 per cent eS TO nti Cisease, which Is Or more importence in the far western, than in the Eeceern and Southern Staces. . Other losses, reported were Ohio, 1, per cent, and Michigan and Colorado, a trace.
Michigan: No varictal resistance noted. Five sprays as applied failed to give satisfactory control. (Bennett)
idea: -Prevalent in Northern, idaho, especially where, San. Jose, seate as present. The spray for that pest seems to control Conyneum blight. (Hungerford)
Washington: Known to occur in practically all sections of the state. (Dept. Plant Path.)
Oregon: leaf, tvig, and fruit spot; bud blight west of Cascades. Twenty wer ecnl of stone Pruvos reported badly spotted in Rogue River Vallcy. Good control where sprayed. (Barss)
aettormia: Found in central California in the cling peach district. The fungus was active much longer than usual. Found it active in May on new wood. (Milbrath) Recent literature 1. Duruz, W. P. California peach blight or shot-hole fungus. Blue Anchor 2 (2): 15, 38. 1925. YELLOWS (CAUSE UNDETERMINED }
From the 10 reports submitted we conclude that yellows occurred about as usual in most of the states, although in Ohio and Michigan it was reported in greater. prevalence than normal. In New York it was reported occurring scatter-
PEACH — Yellows
ingly in Greene and Columbia Cowyaties. Massachusetts reports the disease as be- coming less important. In Michigan it was reported more prevalent this year than usual, occurring in such amounts as to assume the nature of an epiphytotic.- Concerning the situation in that state, C. W. Bennett writes as follows:
"T have spent about two wecks this summer visiting various orchards in which yellows is present and I think we can be very sure that yellows is present in quite a number of orchards in the state, (chiefly in Ber- rien and Van Buren Counties)--- A great many trecs have been condemned by inspectors."
The question as to whether yellows is gradually disappearing is an impor: *
tant one. Accordingly collaborators in a numoer of states on the outer border of the original yellows area were asked as to whether or not yellows occurred in their states. The two negative replies from Indiana and Illinois follow:
"We feel quite confident that peach yellows does not occur in Indiana at the present time.. Neither Doctor Jackson nor I have ever Seen any cases of the disease and I think we have been in most of the commercial peach orchards. Furthermore, the men in. the Horticultural Department who know the commercial orchards from one end of the state to the other, assure me that there is none of the disease present and that there has not been any for a considerable period of time. t seems very strange that such a discase could disappear so completely, but neverthe- less such seems to be the case." (Gardner) |
Writing about peach yellows in Iilinois, Anderson states:
"T think I have becn in every peach orchard in the state, of any size, and have scen them at various seasons of the year. I can say with the utmost confidence that peach yellows docs not occur in this state and probably never has occurred with one possible exception. Professor Burrill reported peach yellows as appearing here at one time in the nine- ties, but while he saved specimens of this discase which indicate yel- lows, I am not satisficd that this was the real cause of the condition.
LT am Quite sure that I am safc in saying that the discase has not occur- red in Illinois during the last ten years."
Table 65. Estimated losses from yellows as reported by collaborators,
1925. Percentage: States reporting ::Percentage: States reporting loss : ae loss : 2 s Maryland, New Jersey =:: 025 : Delaware : Connecticut, Ohio ae trace : Massachusetts, New York, “5 s Michigan is : Virginia, West Virginia
Yellows was reported from Massachusetts, Connecticut, New York, New Jersey,
Delaware, Maryland, West Virginia, Virginia, Ohio, and Michigan. No reports were received from Pennsylvania but it is know to exist there. It was noted July 24 at Hadlyme, Connecticut, and on July 6 in Greene County, New York.
2A7 PEACH - Little Peach; Spray injury ;
LITTLE PEACH
Little peach was reported from Michigan, New York, New Jersey, Delaware, and Maryland. In Michigan it was said to be of considerable importance locally, occurring chiefly in the west central part of. state.
SPRAY INJURY
If there is one particular phase:of spray information that needs clari- fying it is the spray injury problem. Fundamental research is necessary to es- tablish both the particular set of weather, chemical, and other factors combin- ing to cause spray injury; and also the especial features of arsenical, lime- sulfur, and other types, of which we have only a hazy and indefinite conception at present. |
Peaches are particularly susceptible and in the aggregate great losses result in the United States each year. In 1925, apparently, a smaller amount occurred than last year.
New Jersey: Where the amount of lead arsenate in dry-mix was reduced to one pound, only slight injury was observed. (Dept. Plant Path.)
Delaware: Spray injury observed May 22 as typical spotting and marginal burning. Cold, wet weather has predisposed leaves to injury. Dust injury very slight when applied during day compared with night dusting. (Adams)
south Carolina: "Sulphocide" at the rate of 3/4 gallons to 150 gallons of water applied to Mayflower peach resulted in spotting and red- dening of leaves around patches of spray residue. Later, many of the svots fell out leaving a shot—hole effect. (Iudwig)
Indiana: Bordeaux sprays applied April 9, 23, and May 6 resulted in shot-hole effect on leaves. Injury was apparent June 5. (Gardner)
Farley (1) presents certain recommendations among which are the following:
1. Jead arsenate alone or in combination with lime should never be applied to growing peach trees.
2. One pound of powdered lead arsenate to 50 gallons of standard dry-mix is the maximum compatible with safety during growing season.
4. Hydrated lime containing 90 per cent or more of calcium oxide should be used in preparing dry-mix.
4. Great care must be exercised in weighing ingredients before mixing them in the spray tank.
245
PEACH ~ Winter and frost injury; Miscellaneous Diseases Recent literature
i. Farley, Arthur J. Spray injury to peaches. Amer. Fruit Grower
AS (6): 12, is eee WINTER AND FROST INJURY
The same serious aspect of frost injury and freezing of buds discussed under this heading for apple injury, holds true for peachesa There can be no doubt that whenever frost injury is general the total aggregate losses are greater than from any other single cause. This fact is brought out clearly in the 1925 report on frost injury of peaches. Percentage losses reporged weré Maryland, 75 per cent; Virginia, 90 per cent; West Virginia, 99 per cent; Michi- gan, 05 per cent; and Iowa, 50 per cent; while reports from other states not giving definite estimates indicate severe injury.
Delaware: Blossoms killed on April 7; temperature Sussex County 29° F. The percentage losses to different varieties in Kent County were as follows: Elberta, 50 per cent; Carman, 40 per cent; Georgia Belle, 50 per cent. (Adams)
Arkansas: Blossom injury in northern counties cut down edd enormously. (Dept. Plant Path. ) res
Illinois: Temperature of 8 to 20 degrees below zero killed fruit buds except in extreme southern section of the state. (Anderson & Tehon)
Michigan: Blossoms killed by late Prost: most severe in Berrien County. (Bennett)
Utah: Utah was hard hit by the cold weather last winter and while a few favored spots will have a fair crop the Sane the state over is very severe. (Kingsbury)
Idaho: Fifty per cent of the trees in the state killed by severe frost of December 1924. (Hungerford)
Colorado: At Palisades near Grand Junction, Colorado, there were heavy losses in peach orchards due to excessively low temperatures of the preceding winter. The weak trees suffered more than the vig- orous ones. (Brooks) . | a
MISCELLANEOUS DISEASES AND INJURIES
Armillaria mellea (Vahl.) Quel., rootrot, Texas (trace). Bacterium tumefaciens EFS. & Town., anaes Texas (quite prevalent), New Mexico (slight importance), South Carolina (serious in most old orchards and nurseries), Arizona (2 per cent loss). In Georgia 0. OC. Boyd reported as follows: “Several orchards of Hiley, Georgia Belle, and Elberta in Mitchell and Dougherty Counties beginning to lose foliage due to the disease; trees 4 to years old. One orchard, 5 per cent of trees lost."
249 PEACH — ee sous Diseases; Literature persicae |
eee porsiee Sacc., Sees mildew was reported from Florida and Georgia.
‘Clitocybe monadéipha ‘(Morg.) Sacc’., rootrot, Oklahoma aed loss in southern part of state on newly cleared land). ae
Diplodia natalensis Ev., footrot, Florida (not common on peach but caused considerable damage as a footrot of oy trees and.a limb blight of older trees).
' Fusarium spp., rot, California (5).
Heterodera radicicola (Greef) Muell. (Caconema Peepers (Greet) Cobb), root 7 South Carolina (common). Me Hw
' Phoma persicae Sacc., canker, Delaware.
QZonium omnivorum Shear, Texas rootrot, Texas (trace; unimportant), Arizona, (4 per cent loss).
a nigricaris Ehr., Rhizopus rot. Common rot in transit and during marketing (2).
Sphaerotheca pannosa (Wallr.) re, petnes na ilen: Of minor importance in Oregon, -Texas, and New York.
Valsa leucostoma (Pers.}) Fr., dieback, Missouri.
An undetermined leaf and twig blight associated with Fusarium and Rhynchosporium proved troublesome in Coffee and Cherokee Counties, Kansas, ac- cording to R. P. White. 7
Chlorosis (non-par. ), Texas, New Mexico (extremely common this year. Apparently securing : at least temporary relief by the use of iron sulfate).
Mottle leaf (undet. Vy New Jersey (not serious, trace injury, observed in Monmouth and Cape May Counties)
Phoney disease, The phoney disease of peaches in Georgia has been in- creasing in severity. The diseased trees in the old infested areas have in- creased and thé general area has extended quite widely year by year but, so far as known, has not spread beyond the state.of Georgia. At the present-rate of progress, however, it may be expected to reach other states in a very few years. The results of all experiments to control this trouble have been as- tonishingly negative. A tree once affected always continues to be diseased. The absence of any effect of soils, fertilizers, or other.treatment points away from physiological or nutritional types of disease. This trouble, there- fore, stands out distinctly as the least understood of ail fruit diseases, if not of all plant diseases. (Rept. of the Chief, Bureau of, Plant Industry. to the Secretary of Agriculture for the fiscal year ended June 40, 1925).
Recent literature on peach diseases
1. Adams,‘ J. F. The ReaPSeear lesions on peach trees. . Trans. Penin.
_Hort.. Soc. 49 (192A). 22-20. 1925... ead sc i
a eer
2. Anderson, H. W. Rhizopus ret of peaches. Phytopath. i5: 122-124, Feb. 1925. | -3.° Briton-—Jones, H. R. On the diseases known as 'bark canker! and die
back in fruit trees. Jour. Pomol. & Hort. Sci. 4: 162-183...1925,
A. ae BE. D. A storage rot:of peaches caused by a new species of .Choanephora. Phytopath..15: 607-610. Oct. 1925.
5. McClintock, J. Ae Uncongenialty a limiting factor in the use of disease resistant stock. Proc. Amer. Soc. Hort. Sci. 21: 419- 520. “29h.
250 PEACH - Miscellaneous Literature. PLUM and PRUNE ~ Brownrot
6. Plakidas, A. G. Fusarium rot of the peach. Phytopath. 15: 92.98.
7+ Roberts, J. W. Unusual defoliation of peach trees due to active chlorine. U. S. Dept. gr. Off. Rec. 4 (33): 5. Aug. 1925.
8. Smith, R. E. and E. H. Smith. Further studies on Pythiaceous infec- tion of deciduous fruit trees in California. Phytopath. 15: 389- 404. 1925. : ; amr $2
9. Tryon, H. Gumming of dripaceous fruit trees. Queensland Agr. Jour. 24: 120-122. Aug. 1925. .
PLUM AND PRUNE
BROWNROT CAUSED BY SCIEROTINIA FRUCTICOLA (WINT.) REHM. (S. AMERICANA) (WORMALD) NORTON & EZEKIEL
Although slightly less in the aggregate than in 1924 and normally, brown- rot of plums was, as usual, an important economic factor. Twenty-two states reported on brownrot and of these, only three, Massachusetts, Connecticut, and Oregon reported more of the disease than in 1924, while six states reported | less, and the remainder the same prevalence as 1924. Massachusetts, Delaware, | and Oregon reported more brownrot than in averageiiyears. New Jersey, West Vir- ginia, Arkansas, Ohio, and Michigan reported less, while Connecticut, Maryland, Alabama, Louisiana, North Dakota, Kansas, and New Mexico: reported the same prevalence as in average years. The losses reported by the collaborators for . 1925 were as follows: a. |
Table 66. Estimated losses from brownrot as reported by collaborators,
1925. Percentage: States reporting : :Percentage: States reporting loss : :: loss 10 : Ohio os A : Kansas, West Virginia, 8 : Wisconsin a : Georgia 7 : New York, Maryland’ ws | oH .» Delaware, fess. } ee : Connecticut, New Jersey,:: trace ; Virginia, Maine, Minne- : Michigan a : sota, North Dakota, 4. : Kentucky 23 ; California, Arkansas: 2 : New Mexico ; |
——————— ee ee
=
PLUM - Brownrot soa knot ort
Dates and Location of PE iC Pad appearance of brownrot, 1925
May 1 Newark | Delaware : . August 10 Middlesex New Jersey Nay 13 Douglas County Oregon. ~-u- August 25 Madison Wisconsin July 24 Hadlyme ‘Connecticut . August 51 Steel County Minnesota
Oklahoma: Quite plentiful in eastern Oklahoma. Not so abundant in western Oklahoma this year. (Rolfs)
Ohio: Outbreaks are apparently common now owing to the recent rains and to the fact that plums are ripening. (Hesler)
Minnesota: Sapa and Opata varieties found very susceptible to brownrot. (Sect. Plant Path.)
North Dakota: Plum and sand cherry hybrids very susceptible. (Brentzel )
Oregon: Very severe in early part of season; general but not serious at harvest time. In some orchards of Petites at least 50 per cent of the green fruit was attacxed during May, Fresent to a slight extent in Italians also. Over 95 per cent of the prunes grown in Oregon are Italian prunes. (Barss)
Recent literature on brownrot (see also under seach) 1, Lees, A. H., and H. R. Britton-Jones. Plum ashis and brownrot con- BPGle. Jour, Pomed ic. om, Sci... 4; J96-199.... dame lees,
woe etiam, J.d., Ne On. Pervier, and H. 0. Triebold, Bilochemistry oF plant diseases, V. Relation between susceptibility to brownrot in plums and physical and chemical properties. Bot. Gaz. 80: 121- 124... Q0et., 1925.
—— KNOT CAUSED BY PLOWRIGHTIA MORBOSA (SCHW.) SACS.
This disease was not reported as serious in any state this year. [In most caSes it was said to be of very slight importance, although common in neg-~ lected orchards or on wild plun.
Table 67. Estimated losses from black knot as repvortec by collacorators,
Boo Percentage: States reporting > :Percentage: States resorting _loss “if loss 4 > New Mexico A iS : Michigan re : New York, West Virginia:: trace. ;: Virginia, Texas, [lli- a. : Maryland nois, [owa
ae 4 s
. ae oe
ee PLUM - Leafspot; Pockets; Bacterial spot
IEAFSPOT CAUSED BY COCCOMYCES PRUNOPHORAE HIG.
Of six states reporting on leafspot of plum, four indicated less preva-~ lence than normal. The disease was of no economic importance this year, the highest loss reported being a trace to 2 per cent from New York. New Jersey, Maryland, and Michigan reported a trace of loss. In Alabama it was seen on wild plums, causing defoliation.
POCKETS CAUSED BY EXOASCUS PRUNI FCKL. AND E. COMMUNIS. SADEB.
These diseases were reported from Maryland (trace), West Virginia (merely observed), Florida (very common on wild plums wherever grown; 100 per cent fruit infected in many cases), Texas (very prevalent due to cold, late spring), Michigan (of little importance), Wisconsin (same as usual, mostly in northern counties, of major importance on American plums in northern Wisconsin), Minnesota (unimportant, plums were almost a complete failure on account of frost}, | North Dakota (not as common as usual, wild plums, choke cherries and hybrids of these are very susceptible), Nebraska (considerable), Kansas (on wild plum mostly, one report on cultivated plum), New Mexico (same as usual, slight importance).
BACTERIAL SPOT CAUSED BY BACTERIUM PRUNI EFS. . ;
Bacterial spot was reported to be unimportant on plum, the only loss esti- mate greater than a trace being one~half per cent in Texas.
New York: Never very important. Although reported repeatedly as general, it is difficult to determine how much is this disease, and how much is spray injury or Coccomyces. (Chupp & Pierstorff)
Georgia: This disease did not assume any commercial importance in the few plum orchards in the Fort Valley section. One orchard}, which in) So eAN hae: O5 per cent of the trees showing dead or dying twigs caused by this organism, had only a slight infection in 1925 and no dead twigs due to girdling by cankers. (Dunegan)
Oklahoma: The foliage and twigs of all the Japanesé varieties are more or less infected. Foliage injury not so mrked as-last season. (Rolfs) |
Minnesota: Found on Red Wing plums only. lLeaves only affected. No fruit on trees because of frost. (Sect. Plant Path.)
Other states reporting its occurrence on plum are Delaware, Maryland, Alabama, Louisiana, Arkansas, Ohio, and Michigan. An interesting report on the relative susceptibility of plum varieties in the variety orchard of the Ohio Axperiment Station was prepared by Hesler (Pl. Dis. Reporter 7: 86-88. Sept. 15, 1925). The only variety particularly susceptible to infection on leaves, twigs, and fruits was "Gee Whiz". None of the best commercial Domestica plums
PLUM ~— Bacterial: spot; Frost injury; Drought injury
were susceptible, with the exception of Coates Improved French prune, which showed heavy infection on fruit pedicels. The commercial imported Damsons were slso free of the disease. The triflora plums, Shiro and Burbank, were the only commercially valuable varieties that’ showed high susceptibility.
WINTER AND FROST INJURY
The states of Delaware, Maryland, Michigan, Wisconsin, Minnesota, Iowa, and South Dakota report great reduction in the crop due to killing of the blos- soms by late frosts. In some of these states this injury was a limiting factor in crop production. For instance, in Maryland the loss was thought to be about JO per cent due to killing of young fruits by a May freeze. In Michigan AO per cent loss on account of late frost.occurred, while in Minnesota and Iowa 90 and 50 per cent loss was estimated respectively. The crop was practically a total . failure in Minnesota.
Idaho: We found considerable winter injury on prunes in the Payette and Boise Valleys. The location of the injury was usually on the south side of the trunk or in the crotch and often extended from the ground line up to the lower branches and in some cases the ex- posed branches were also affected. In some instances the general growth conditions of the tree did not seem to have been affected, but in others, the branches immediately above the injury were dy- ing. A Cytospora was present on some of the injured areas. (Brooks)
Washington: Italian prunes in the Walla Walla section particularly and also more or less generally over eastern and central Washington have shown a particularly heavy drop at the time the fruits were nearly full grown. Many of the fruits not dropping showed drought spot or gum spot in the flesh of the fruit. The condition was analyzed to be largely the result of severe winter injury to the trees during December 192A. This delayed effect of winter injury reduced the yield of marketable fruit to a small fraction of what was expected by growers. Injury was also apparent on the tree in the form of delayed effect of injury to twigs and branches. On the branches the progressive effect of winter injury became evi- dent after the advent of dry, hot weather. On those branches where this progressive yellowing and death took place the entire set of fruit either dropped off or was of such poor quality as to be of no value. This delayed effect of winter injury coupled with the reduced set.of fruit caused by spring frosts was a severe blow
to the industzy in the affected regions. (Dept. Plant Path.)
DROUGHT INJURY
leafroll and fruit drop, of unknown cause but probably due to lack of moisture, was more severe than for.the last five years in Idaho, according to Hungerford.
Leafrolling and dropping cue to excessive transpiration and drought fol- lowing a cool,wet spring was more important than usual in Oregon. It does not
254 PLUM ~ Drought injury; Other Diseases
usually occur in the irrigated sections of the eastern part, but in 1925 it was general throughout the state. Barss said that injury to growth and fruit set. tingis expected to show up next spring.
Gum_spot_of fruit was general and very important in both eastern and wes- tern Oregon. ts occurrence is unusual in irrigated sections in eastern Oregon, where it showed up this year. t was especially bad in the Milton-Freewater district, where 80 to 85 per cent of the prunes were graded second grade due to this trouble. (Barss)
OTHER DISEASES AND INJURIES
Armillaria mellea (Veh1) Quel., rootrot, Oregon (general in western part on old oak land}.
Bacterium tumefaciens EFS. & Town., crowngall, Florida (on nursery stock), Oregon (probably general but only locally important).
Fumago vagans Pers., sooty mold, Washington.
Ozonium omnivorum Shear, rootrot, Arizona (1 per cent loss}.
Fodosphaera oxyacanthae (DC.) DBy., powdery mildew, Florida (causing ser- ious twig blight on growing trees).
Tranzschelia punctate (Pers.)} Arth., rust, Florida, Texas, California, and Oregon. In Florida it was collected on wild plants near Gainesville on which it caused defoliation in the late summer. In Oregon, according to H. P. Barss, in one four-year old orchard this disease caused bad defoliation in Date prunes, aS much as D cent in spots, while Italians alongside were not badly affected. in another orchard in the same county, however, Jtalians Were ser tously affected. In California, Milbrath reports it in the central and north- ern parts of the state causing a loss estimted at 0-5 per cent.
Valsa leucostoma (Pers.) Fr., dieback, Texas, Missouri, Kansas.
Black-end (non-par.), Washington.
Chlorosis (too much lime), Texas (traces).
Rough bark disease (non-par.), Washington (on Italian prune).
Leafspot (non-par.), Washington (Yakima Co.)
ry
Sian oat 1 ey
~J <1 ©
Recent literature on plum diseases “ P 3 “ a = = 7 T 4 BR} 1. Ducomet, V. La rouilie du prunier. Rev. Path. Veg. & Entom. Agr. im BT ahd
ll: 202-207. ct.-Dec-. i92d.
2. Entomologists and pliant pathologists of the Agricultural Experiment otations and Colleges of Agriculture. Spray Calendars for var- - 7 ae we : Z d lous sections of -the country. mer. Fruit. Grow. Mag. 45 (2): Feb. 1925.
4- Mix, A. J- Biological and cultural studies of Exoascus mirabilis. Phytopath. 15: 214-222. 1925.
4. Smith, R. H., and E. H. Smith. Further studies on Pythiaceous in- fection of deciduous fruit trees in California. Phytopath. 15:
309-A0A. 1925.
255 CHERRY ~ Brownrot
CHERRY
BROWNROT CAUSED BY SCIEROTINIA FRUCTICOLA (WINT.) REHM (S. AMERICANA (WORMALD) NORTON & EZEKIEL)
This disease seemed to be of comparatively slight importance in most of che cherry producing states this year. Only Indiana and Oregon reported greater than average prevalence. >
The losses from brownrot of cherries for 1925 were reported as follows:
Table 68. Estimated losses from brownrot as reported by collaborators, 1925. Percentage: States reporting -::Percentage: States reporting fewest se ee OSs! 4 | | 10 : California, Maryland 2% 1.5 ; New York e : Michigan ; o: ut : Ohio; “diianois A : New Jersey ft -5 : Wisconsin 4 : Connecticut, Oregon gee 25 2 Delaware 2 : New Mexico, South Car-:: trace :; West Virginia, Iowa, o—oling, Virginie, Ark=<*- i: 2 to Maine, Ken tatkey
2 ansas “a :
==
New York: Better control measures this year because canners brought pres-.
sure to bear on the growers. (Chupp & Pierstorff)
: No blossom blight has ever been nioted in Arkansas. (Dept. Plant
Indiana: Serious fruit rot in southern Indiana; 10 to 15 per cent inci- dence reported in a car from Floyd County PERS ah by United States inspectors. (Gardner)
Kansas: Found on small green cherries. Unusual. (White)
Abundant blossom blight and severe rot of green and ripened fruit. spraying not a general practice for this disease. Weather very favorable. Dry, hot weather in late June and July checked the outbreak Lai seal! (Barss)
Oregon:
California: Very bad. Occurred in all cherry districts, causing loss of 10 per cent. Disease followed spring rains. (Milbrath)
“According to Brooks and Fisher (1) spraying for the control of brownrot in the northwest cherry sections has been very successful. The disease is said to be one of the most serious problems in successful cherry growing and market- ing in that section. ; “ey
256
~_ -
Recent literature ‘a ae
1. Brooks, Charles and. D. F. Fisher. Sor
ay the Northwest. Amer. Fruit Grow. 45>
g for brownrot control in )ts 105 28g SAsen 192
LEAFSPOT CAUSED BY COCCOMYCES HIEMALIS HIG.
: ‘a Bes: - Of the 1b states reporting on leafspot, 11 reported less than normal prevalence, while Connecticut and Oregon reported more than usual. Dry weather
Was mentioned, in many. cases, as the cause of the reduced amount of leafspot.
> i : ~ Table 09. Estimated losses from leafspot as reported by collaborators, | ES 2 ian ees ee eee ‘ Percentage: © Statés’ reporting - ::Percentage:.. States reporting . loss : bol ee 2: _loss : 10 : Mary land ‘. “45 : New York, New Jersey, 5 : Michigan, Towa o: : Ohio, Lllinois, Wis= 2 : Kentucky +3 :- consin fi : Kansas, Virginia 2 “trace : Delaware, West Virginia, : a ih '. bie Pre Sis
New Jersey: Not important this year. Appeared late.in the season. The
weather was hot and dry at picking time and consequently the dis— e was not ‘Severe. (Martin)
Florida; lLeafspot was apparently in all sections of the state where & plant grew- It was of little importance, however. (Weber)
Michigan: Of some importance locally; minor in the southern half of the state, but heavy, late infection in northern half. lIate infection result of dews. Pemperature rela tively high during the period of infection. (Bennett)
n: Leafspot is not feared by leading cherry growers because it so well kept under control by spraying. Lime sulfur and arsen- of lead applied wet is a general practice. Some minor dusting
being tried out. (Vaughan)
Missouri: Much damage to unsprayed trees which were often Manaw ) (Maneval
Nebraska: Common and severe. (Goss) Kansas: .Checked by proper spraying with bordeaux or lime-sulfur. (White) Oregon: Unusually abundant in western Oregon; caused much damage to small
crop of sweet cherries set. Attacked pedicels, as well as leaves, and caused shrivelling of ifruit. Long, cool, wet spring. (Barss).
:
257 CHERRY ~ Tesreeee: Frost injury; Winter injury
Observations on leafspot in Rae gonad n (2) show infection is caused by spores discharged about June 15. In cool, moist weather the spray program will hold the disease in check.
Dutton and Wells (1) give a brief desoription of the disease and some data as to its effect on yield and growth of trees. Trees defoliated in prev- ious years were found to produce relatively few small blossoms. The total pro- duction and the vigor of the trees following defoliation were greatly reduced. In the control investigations, the authors found that Pyrox could not be used satisfactorily on cherries because of serious foliage injury. lLime-sulfur is satisfactory for control, caused no foliage injury and did not reduce the size of the fruit.. The authors recommend liquid lime+sulfur diluted at the rate of three gallons to a hundred for the control of leafspot on sour cherries in Michigan.
Recent literature
1. Dutton, W. C., and H. M. Wells. Cherry leafspot: ‘Residual effects end Gotrol <)\MichizaniAgrejExp. Stas Buls 2475-05. 19254
Po RURSe let ie te, °F. TBs Morrison, and W. H. Ebling. Plant disease in-
vestigations of the Wisconsin Station. In (Annual Report of Dir- ector) Wisconsin Agr. Exp. Sta. Bul. 373: 5-16. 1925.
PROST INJURY
Considerably more than normal frost injury was reported from Delaware, Maryland, Virginia, Illinois, Michigan, Wisconsin, Iowa, and Idaho. High losses were reported from some of these states as indicated by the following table:
Table 70. Estimated losses from frost as reported by collaborators,
1925). Percentage: ‘States reporting | ::Percentage: States reporting LoS iaaee Pee ae | ie loss 90 : Maryland, Virginia 23 25 + Wisconsin 80 : Lowa ie i) see : New Mexico 50 : Michigan sire mie Oi
WINTER INJURY
Washington: Cherries in all parts of the state were severely injured by the sudden drop in temperature which occurred in December. Some trees were killed outright, but others were injured so that parts have continued to succumb at various times as the season progresses, (Dept. Plant Path.)
2508
CHSRRY — Misceliancous Diseases
MISC | LLANES OUS DISEAS aS AND INJURIES
Armillaria mellea (Vahl) Quel., rootrot, Washington.
Blight reported from Michigan and Kansasg Bacillus enylovorus was iso- lated from the Kansas material in Kansas. A letter from Bennett of Mi chigan reports as follows: "Your may be interested to know that we found.considerable fireblight on cherry fruits in Michigan this summer. I have’ isolated the or— ganism and have obtained typical fireblight. on apple and pear fruits and on apple twigs, so that I think there is very little doubt but that the cherry spot was caused by Baciilus amylovorus."
Bacterium cerasi Griffin, bacterial gummosis was unusually severe on sweet cherries in Oregon, according’ to Barss, "The results of this. disease seem to be unusually severe this season. In the first place the extreme low: temperatures (below zero) of the last Christmas season may have accelerated the canker and girdling ee eet’ of the bacteria attacking tree bodies of sweet cher ries. In the second place the cool, moist spring seemed to provide an:. unusual amount of spur blight. and leafspotting. These leafspot areas are aber large. They frequently drop out and leave a lacy effect on the trees."
Barss (1) says that this disease is the greatest problem in young sweet cherry orchards in Oregon and Washington. Sour cherries are not attacked.
_ Bacterium pruni EFS., bacterial spot, New York.
Bacterium tumefaciens EFS. & Town., crowmgall, Washington.
Cercosvora cerasella Sacc., leafspot, Florida.
Cladosporium carpophilum Thuem., scab, Iowa.
ExOascus cerasi (Fckl.) Sadeb., witches! broom, Washington, Oregon.
Podospheera oxyacanthae (Fr.) D By., powdery mildew, was reported to be more prevalent in New Jerscy than usual, causing 5 per cent loss in Iowa, and presen., bus, er no importance, in Connecticut and New York
An undetermined powdery mildew was reported for the first time on cher- ries in Minnesota. : "Powery mildew stunting Sand cherry and Zumbra cherry in nursery rows at Owatonna. Not on other varieties." (Div. Plant Path.)
Arsenical injury caused considerable loss on Morellos in New York. Ac- cording to oe and Pierstorff the canners served notice on the growers this spring that unless the cherries were sprayed well enough to keep the maggot down to a cent or less the crop would not be accepted. Consequently, many growers used too much arsenic and caused serious injury on ripening Morello fyuit- In one large orchard in Niagara County where the grower put on too heavy applications, from 5 to 50 per cent of the fruit on diffcrent trees was destroyed. Similar oe was reported from Orleans, Monroe, and Wayne Count-— ies.
Gummosis (Undet.}) was reported on Schmidt sweet cherries in Ontario. County, New York; and Washington.
Leaf crinkle (cause unknown, probably soil deficiency), Ideho (noted in several orchards in Lewiston region. leaves have somewhat the appearance o mosaic infected plants).
A physiological trouble of sour cherries in reported by Frank from west— ern Washington as very abundant on Montmorency, less abundant on Morella, in ary Seasons. The fruit is gla ee bitter tasting, and may be brown inside. (Dept. Plant Path.) i ASO et : ou Tranzschelia punctata froin ) Arth., rust,, South Carolina.
APRICOT _ Miscellaneous Discases
Recent literature on sherry diseases
1. Barss, H. P. Avoidance of bacterial gummosis of cherry. Better Prout 19° (is dane 1925.
2. Brown, WW. H. ‘The cherry in New South Wales. A discussion of the probloms. Agr. Gaz. New South Wales 36: 121-134, 199-208. 1925.
45- Marre, F. Le Botrytis des cerisicrs. Jour. Agr. Prat. AS. year? Nan-arsin) AGe Is
APRICOT
Blig ht, Said tobe due to Bacillus _anylovorus (Burr. ) Treve, Was re- ported from Florida and Texas. :
Bacterial spot due to Bacterium pruni EPS. was reported from Texas.
oe duc to Bacterium tumefacios EFS. & Town. caused a loss esti- mated at 1.5 per cent in Arizona, according to Streets.
Scab causcd by Cladosporium carpophilum Thucm. was reported from Texas (loss one-half per cent).
Blight caused by Coryneum beijerinckii Oud. was said by Hungerford to be, as usual, the most important disease of apricots in Idaho. It was general and destructive in California, according to Milbrath, who estimated a loss of 6 per cent.
Rootknot caused by Heterodera radicicola (Grecf) Mucll., (Caconema radicicola (Grecf) Cobb), was reported from Arizona (caused the death of a young apricot tree near Phoenix).
Rootrot caused by Ozonium omnivorum Shear killed about one per cent of the trees in the soxthern half of Arizona (Strects).
Blossom and twig blight caused by.Sclerotinia fructicola Rehm (S. ameri- cana (Wormald) Norton & Ezckiel) was an important factor in the Santa Clara, Sacramento, and San Joaquin Valleys of sen eo according to Milbrath, who estimated a loss of 5 per cent. Rudolph (5) states that the Monilia blossom blight of apricots has become increasingly destructive in California in recent years, due most probably to extensive planting of susceptible varieties. In favorable seasons it may be followed by fruit rot. The Sclerotinia stage is very rare in California. Control is difficult, but may be attained by succes- sive spraying with Bordeaux 8-8-50. Sulfur compounds should not be used, since the apricot is exccedingly liable to sulfur injury. ,
Green fruit rot caused by Sclerotinia sclerotiorum (Lib.) Mass. caused considerable loss in some orchards in California. The.reduction in yield for the state was cstimated by Milbrath at one-half per cont.
Black heart caused by Verticillium sp. (2 alboatrum Reinke & Berth.)
"A considerable factor throughout California; loss .2 per cont. There seems to be some correlation between potato and fruit tree infection by Verticillium." (Milbrath)
: Fruit spot (undct.) was reported from Kansas. "Alternaria and Venturia spores in lesions. Looks like scab spots.. Lesions brown, sunken, firm at first. later they become larger, more sunken, and softer." (White)
260 GRAPE — Blackrot
Recent literature on apricot discases
ie Anon. Peach DLignt, shop-nole fungus, and the peach twig borer. Blue Anchor 2 (11); 16, 33. Nov. 2925.
2- Entomologists and plant pathologists of the agricultural experi- ment stations’ and colleges of agriculture. Spray calendars Tor various sections of the country. Amer. Fruit Grower Mag. 45 (2). Beis ae ys
4. Hoerner, G. R. Advances achieved in orchard dusting. Better Fruit
19 (Ode I-05, 28 ene 4925.
A. Nicholls, W. H. Apricot growing. Diseases. Jour. Dept. Agr. Victoria 23: 105-100. Feb. 1925.
5. Rudokph, B. A. Monilia blossom blight (brown rot) of apricots. Galifornia Agr \' Hips) Ste. Bul. 4032 1-55. ‘Feb’. 1925.
6. Smith, R. E., and E. H. Smith. Further studies on Pythiaceous in- fection of deciduous fruit trees in California. Phytopath. 14;
309-404. 1925.
DISEASES OF SMALL FRUITS
GRAPE
The total grape production in the United States in 1925 was 1,967,160 tons compared to 1,763, 742 tons “im 1924. The total-crop value in-i925-was $66 ,969,323.00 while that of 192A was $73,227,580.00. In the order of produc- tion the states ranked as follows in 1925, California, New York, Michigan, Ohio, and Pennsylvania.
The survey of the various diseases which have caused economic losses to the grape crop indicates that in 1925 the loss from fungous injury and other Causes Was considerably below normal.
BLACKROT CAUSED BY GUIGNARDIA BIDWELLII (ELL.) VIALA & RAVAZ
Of the states reporting on blackrot of grapes in 1925 only one reported greater prevalence than in 1924 or normally. This is a very exceptional record for blackrot, which, for a long period of years has been the most important dis— ease of grapes in the eastern United States. Eleven out of eighteen states re- ported less.than average prevalence. The only states from which reports of serious injury were received were Maryland, Kentucky, and South Carolina. The 'losses reported are given’ in table 71...”
261 GRAPE ~— Blackrot
Table 71. Estimated losses from blackrot as reported by collaborators,
1925. Percenzage: States reporting °: Percentage: States reporting loss : pitta 02M: loss 10 : Maryland oe SS) : Delaware, Alabama 8 : Kentucky Fi 2 : New Mexico v : Virginia BA 1 : West Virginia 5) : South Carolina, Miss- :: 45 --Ohio, [iteis, Conn= issippi, Georgia, 2 2 ecbicut Idano, Texas su trace :; Arkansas, Wisconsin, A : North Carolina vs : Kansas, New York
omer ates sae
Dates and location of earliest reported appearance of blackrot Ie
June 9 Westminster South Carolina June 22 Erie County New York June 15. Thomas Georgia July 12 New Brunswick New Jersey June 22 Newark Delaware duly 21 » Westford Connecticut
Virginia: The only disease of cconomic importance this season on Mus— catine grapes in Tidewater region. (McWhorter)
North Carolina: lIess prevalent on account of dry weather. (Fant)
betmeta: Mostly Leatspot injury.“ Only siight’ injury te. frure 1 epereed from southernmost counties. (Dunegan)
Florida: Reported from several widely scattered points in the state. Although the fruit of Muscatine varieties is quite resistant
the leaves are quite susceptible. (Dept. Plant Path.)
Louisiana: Some Muscatine grave varieties severely diseased. Others entirely free. (Tims)
Oklahoma; This parasite is umasually destructive this season, especi-
ally in the eastern part of the state where as high as 50 per cent.
of the crop in some of the unsprayed orchards has been destroyed. (Rolfs)
Ohio; 23S severe in the state than last year. In fach wery DL Etie vne= ported. (Young)
Michigan: Little or no loss in most vineyards. Difficult to find any trace of rot in many plantings. (Bennett)
Manns and Adams (2) found that infection may occur any time after the new shoot is one inch long, although the macroscopic lesions may not appear un- til the fruit is two-thirds or more grown. No number of sprayings can. control blackrot after initial infection has taken place. Dry weather may arrest the disease. Primary infection at the base of new shoots is thought to be the means of carrying over infection for the succecding year.
262 7 rae GRAPE — Downy mildew
Recent literature on blackrot _
1. Guba; BH. Fo Blackrot, and mildew of the Vine. Amer. Fruit Grower
45 (5): 1. deen
2. Manns, T.-F., and J. F. Adams. (Report of) Dept. of Pl. Path. and Soil Bat Pare eay + In Delaware Agr. Exp. Sta. Bul. 139: 24-29. 4925 | :
DOWNY MILDEW CAUSED BY PLASMOPARA VITICOLA (BERK. & CURT.) BERL. & DETONI
Downy mi rae was of considerably less importance this year than in aver- age years, only Minnesota reporting greater than average prevalence.- New Hamp- shire, New lork, Delaware, Virginia, Ohio, and Indiana reported downy mildew to be of slight importance. Losses were estimated as follows: Maryland, 2 per cent; Alabama, 1 per cent; Ohio, .5 per cent; Virginia, Kansas, and Arizona, a trace.
Dates and location of earliest revorted appearance of downy mildew, 192
July 4 Madison Wisconsin August 12 Maryland July 7 St. Paul Minnesota August 13 Indianapolis . Indiana July 20 Stratford Connecticut August 15 Dover | New Hampshire July 20 Green County New Jersey August 1 Freehold -. Delaware
Massachusetts: Widespread but development checked by dry weather. (Osmun & Davis)
‘New York: Rare on cultivated grapes. Common on wild grapes. (Chupp)
Maryland: The chief cause of premature defoliatién of Niagara grapes in at least one vineyard. It was present on practically all of the vines of this variety and as a result of it, many of the leaves were curling, dying, and falling prematurely. (Haskell)
Illinois: Dry weather throughout most of the season reduced mildew. (Anderson & Tehon)
Recent literature
1. Cadoret, A- la bouillie basique bieue contre le mildiou. Compt. Rend. Acad. Agr. France ll: 686-6868. July 1925.
2. Guba, E. F. “Blackrot and mildews of the vine. Amer. Fruit Grower
45 (5): 12. 1925.
4. Kotte, We Observations sur: la Wes evans de certains hybrides au mildiou et au roterbrenner. (Observations on the resistance of certain hybrids ” to miiiew and. 'roterbrenner'). Prog. Agre et Vitic. 83: 13-15. 1925. : | : ea
263
GRAPE -— Powdery mildew; Anthracnose
4. Manuel, H. Le. Downy mildew of the grape. Agr. Gaz. New South Wales. 36: 751-752. Oct. 1925;%
5. Ravaz, L. Chronique: le temps. - Le mildiou. (Current events: The weather. - Mildew.} Prog. Agr. et Vitic. 83: 581-586. 1925.
POWDERY MILDEW CAUSED BY UNCINULA NECATOR (SCHW.) BURR.
The only state, of the ten reporting the disease, in which powdery mildew was said to be important was Califormmia, where a loss of 2 per cent was esti- ~ mated by Milbrath.
Illinois: Very slight irfection. General throughout the state late in season. (Anderson & Tehon)
Michigan: A small amount of mildew is present on the leaves in a few vineyards. Generally rare. (Bennett)
Oregon: Not very important. Probably general with host. Controlled with sulfur-dust. (Barss) —
California: An important factor. Continuous dusting saved many crops. (Milbrath).
Recent literature
1- Castle, C. B. Combination tractor and sulfur blower. Amer. Fruit Grow. 45 (4): 22. 1925.
2. Guba, E. F.. Blackrot and mildews of the vine. Amer. Fruit Grow. fe ory tes Teh.
4. Fonzes—-Diacon. La lutte contre l'oidium. Progr. Agr. et Vitic. 83:
16-18; 40-42. 1925.
A. Vermorel, V. Le permanganate de potasse contre l'oidium. Prog. fer. & Vities 64; 60-03. July 26, 1925.
ANTHRACNOSE CAUSED BY SPHACELOMA AMPELINUM D BYs (GLOEOSPORIUM ‘MPELOPHAGUM (PASS.) SACC.)
Anthracnose was reported this year from Delaware, Maryland, Florida, Alabama, Mississippi, Kansas, and Porto Rico. Delaware: Found overwintering on canes. (Adams)
Florida: Of frequent occurrence throughout the grape growing sections. (Rhoads)
264 GRAPE — anthracnose; Deadarm; otged frost ie Other Diseases
ae than 1 per cent.
Mississippi: Light Bu and, Shight damage. Beal) ite es ; Kansas: .One ronarh nie nse ak ae ee ae (White)
-DEADARM CAUSED BY CRYPTOSPORELLA VITICOLA (REDDICK) SHEAR
Deadarm was reported: from New. York, Delaware, South Carolina, and Kansas. The first appearance noted in New York was on June 12 in Orleans Courntty. In south Carolina it first appeared on ssh el, at Waterloo, and in Kansas on June 9 ee ak Doniphan varie :
Sra harice, . Present in (Chautauqua district most commonly. (Chupp ‘&
Pierstorff) South Carolina: Slight to moderate injury locally. In vineyards in Sand Hill and Piedmont regions. (Fenner ein
SPRING FROST INJURY
Frost injury as a factor of grape. Re was very great in ee some of the ees statements follow:
Wisconsin: Temperatures were low enough to kill buds and vines, _The
vines started growth after being killed back by the frost but — only a few Diegeuae a eie en second ‘eres, (Vaughan)
Frost on May 23 and 24 killed’ pack | vines to the old wood in Also killed all the blossoms. New set: of blossoms (Anderson & Tehon)
Tilinois: many cases. produced 10-per cent of crop.
Virginia: Complete killing on higher cue eades Geter
_ OTHER DISEASES. AND. INJURIES "_
crowngall, was reported from Florida
Bacterium tumefaciens EFS. & Town., also.on an unidentified variety at
(found on Alicante Bouschet: at Grand Isiand; Dade City. - Rhoads), Michigan, New Mexico, Washington, and Oregon. Botrvtis sp., gray mold rot, was important in some sections of Oregon, _ Causing rot of fruit on the vine and after picking. In the vicinity of: Grants Pass the loss on Tokays was about 25 per cent. .Rains” at picking time favored its development. -In California also it was much more prevalent than usual and’ was Serious in many localities, especially in the’ coastal cna ceike OCU ET Ens:
as a blossom rot in the spring and internal cluster rot. in the fall. : a grat! Red
GRAPE - Other Diseases; Miscellaneous Literature
Clitocybe monadelpha (Morgan) Sacc., according to Rhoads (10) causes a common and sometimes destructive rootrot in the Ozark section of Missouri, ar probably in other southern states.
Exosporium sp.-, Florida.
Heterddera radicicola (Greef) Muell. (Caconema radicicola (Greef) Cobb} root knot, California (loss 1.5 per cent).
Isariopsis clavispora (Berk. & Curt.) Sacc., leafspot, South Carolina (unimportant); Florida (causes premature defoliation).
felanconium fuligineum Leesernee & Viela) Cav., bitter rot, Delaware, Florida.
Ozonium omnivorum Shear, rootrot, Texas, Arizona.
Pestalozzia uvicola Speg., leafblight, Delaware, Florida, Ohio (said by~ Young to be new to state).
Septobasidium sp.-, Florida.
Chlorosis (non-par. ) Common in Tees ee to excess of lime) and New Mexico. ry. Mosaic, cause unknown, New York, Westchester County. A mosaic-like trou- ble affected one plant, which showed mottled leaves, dwarfed growth, and set no fruit, while other plants in the same arbor set fruit abundantly. (cea
Recent literature on grape diseases
1. Bioletti, F. fT. Black measles. Calif. Grape Grow. 6 (9): {= Sepus ge deo
2. Castella, F. de. Vine black spot and erinose. Jour. Dept. Agr. Vaetoria 24; 442-4455). «July 19256:
AI
Faes, H. Les Rotate? resistant a la chlorose. Progr. Agr. et Vitic. 83; 85. Jan. 25, 1925.
An cei Re. Les noc cenee (eonel.] IV. Ie pourridie des vignes de-~ terminé par le Roesleria ue aeer. Traitement Jardinage 12: 328- ae JULY LG 2h
He jae a B., and P. Patev. Die gefundenden Reben-Krankheiten in Bul- garien. Rev. Inst. Rech. Agron. Bulgarie 4: 2-4, ella AN. Tee (Germany summary) :
6. Pfeiffer, GC. Der Grind oder die.Mauke, Krebs der Reben. Kranke Piianze 2: 16-20. 1925. | .
7+ Ravaz, L. Y a-t-il des vignes resistantes au pourridie? Prog. Agric. 6t Vitices 42: 174-175-.. 1925.
8. Ravaz, Le and G. Verge. Sur une maladie de la vigne, 1'excoriose. Compt. Rend. Acad. Sci. Paris 180: 313-315. 1925. Phoma flaccida associated.
9- Rhoads, Arthur S. The principles and practices in the prevention of
grape diseases. Florida Fruits and Flowers 3: 16, 18-20. OP oi
10. Rhoads, A. S. Rootrot of the grapevine in Missouri caused by Clito-— cybe tabescens (Scop. ) Bres. Jour. Agr. Res. 30: 341-364. 1925.
266 STRAWBERRY — Gee Leafscorch
STRAWBERRY
LEAFSPOT CAUSED BY MYCOSPHAERELLA FRAGARIAB (TUL.). LIND.
It is noteworthy that leafspot : ‘of. Pbessenes TlLes seemed to be eonsider- ably above the average in prevalence in 1925... New. York and Iowa reported the Same prevalence.as in 1924, but New :Hampshire,_ Virginia, Connecticut, Louisiana, and Kansas reported more. According to the collaborators, the losses caused were as follows: Kansas, 3.per cent; asa 6 per. a New York, 1.5 per cent; Texas, J. per cent. Ne , :
Dates and location of earliest reported appearance of lJeafspot, 1925
February 15. Denham Springs ieuadshanay: . Jans 22). : reen County New York May f Lawrence County Indiana July.15 Portsmouth New Hempshire May Neosho. _. Kansas _ October 8 - Westport Connecticut
Vermont: Believe that it is above normal in:severity. Have had at least one report where it was really destructive. (Iutman)
New York: Very common and frequently destructive. Most injury when spots appeared on fruit pedicels. (Chupp)
Louisiana: Found quite commonly on plants shipped in from Arkansas. It appeared as early as February 15 and continued to the end of the strawberry season about the last of May. (Edgerton & Tims)
Illinois: Very light on account of dry spring. (Anderson)
Kansas: Unusually severe: this season. The frost of May 24 reduced the crop about one-half in this state. This was followed by abundant ” leafspot infection causing 100 per cent death of plants by June 15 in some cases. If cevere weather is experienced this winter it is probable that many larze commercial patches will be des- troyed due to the weakened condition of the plants. (White)
Varietal susceptibility to eee Of strawberries was reported as fol- -lows by White of Kensas:
Severe infection - Burrill, Magic.Gem, Kellog Prize, Cooper. Moderate infection — Gibber, Eblong, Dunlap.
Slight infection —~ Howard, Baton.
Very slight infecticn ~ Kéllogg Premier.
LEAFSCORCH CAUSED BY DIPLOCARPON EARLIANA (ELL. & EV.) WOLF
This disease was reported from New York, Delawarc, Maryland, Indiana, and California. It was said to be more phe a ia in ere this year.
coy N@RAWBERRY — Leafscorch; Stem nematode; Rootrots; Other Diseases
According to Horne of California, it occurred on wild strawberries trans— planted from lake Tahoe district. The fungus developed in both places but did not spread to other varieties at Berkeley.
According to Birmingham (1) the control of leafscorch consists mainly in the selection of resistant varieties, the destruction of diseased material, and early spraying with bordeaux mixture.
Recent literature
1. Birmingham, W. W. lLeafscorch of strawberry. Agr. Gaz. New South Wales 36; 213-214. Mar. 1925.
STEM NEMATODE, TYLENCHUS DIPSACI (KUHN) BAST.
According to McKay of Oregon, this is the first year that the nematode disease has been found away from the coast on cultivated strawberries except at Corvallis. The grower who reported it said that about 10) per cent of the plants, in a half-acre of old clover land, were badly affected. Young plants from the Same source, planted at the same time on land adjoining this patch, but that had been in oats the previous year, had only 3 per cent infection. It is not known definitely whether the clover strain goes to the strawberry or vice versa, but there is some evidence to the effect that it does.
ROOTROTS DUE TO VARIOUS FACTORS
Maine, Massachusetts, Connecticut, New York, Florida, louisiana, Jiianews, Wisconsin, and Colorado reported rootrot.
Faorida: Rootrot has been the most troublesome and destructive disease during the past season in strawberry. plants in Florida. It has been reported from practically every strawberry growing region and the losses from this disease in many instanees have been consider- able. In most cases the diseased plants yielded a Fusarium. There may be other associated organisms that may be important. (Rhoads)
Massachusetts: Instances of 10 to 20 per cent loss of plants due to rootrot. (Osmun & Doran)
New York: Important in some soils. Rootrot follows any weakening of the plant. Jn one field in Nassau County the loss wiil probably be 90 per cent of the crop. (Chupnp)
OTHER DISEASES AND INJURIES
Botrytis rot was reported from Delaware, Virginia, Arkansas, Indiana, Oregon, California, and Connecticut. Barss reported that in Oregon it was very serious this year due to wet weather throughout the spring picking season. A loss of 4 per cent was estimated by Milbrath in California.
265 STRAWBERRY ~ Other Disesses; Miscellaneous Saab. ic
RASPBERRY —- Anthracnose
Dendrophoma obscurans (B12. & Ev.) H. W. Anderson, leaf blotch, New York, Indiana, and Florida. According to the anual report of Florida it was found | for the first time in that state in two widely separated sections... This is
the first report from New York, aiso (specimen in Pathological Collections).
Phytophthora sp., Arkansas. Rot, apparently caused by Phytophthora:is ~ present to a limited wee | Dry weather appears not to have favored rot in the field. (Dept. Plant Path.)
Rhizopus nigricans Ehr., leak, Indiana, Virginia.
Sclerotinia sclerotiorum (Lib. ) Mass-, Florida (seattered, not important).
Sphaerotheca humuli (DC.) Burr, powdery mildew, New York, Maine.
Chlorosis caused by too mich lime was reported from Texas. In Idaho a Bias of unknown cause was very important yellowing the leaves, rotting the crowns, and killing the plents. It was very important in southern Idaho on strawberries,under irrigation.
Mosaic (undet.) --Reported from New York and Canada.
Yellows (undet. ) Wisconsin ( Arome badly yellowed. Other varieties ad- Jacent not diseased), Minnesote (moderately abundant on some varieties), Oregon (present in western On ehes and possibly widely distributed).
Recent ae ieee on strawberry diseases 1. Beaumont, A- Strawberry diseases in Devon and Cornwall. Asime.- Rept. Dept. Plant Path. Seale-Hayne Agr. Coll. 1 (1925-1924): 12-43: 1925?
2. Chifflot, J. Maladies cryptogamiques attaquant les Pr aicmeey Rev. Hort. Algerie 29: 113-116. June 1925.
4. Richards, B. L. Plant Pathology. In Utah Agr. Exp. Sta. Bul. 192 (Bienn..Rept. Director 1923-24): 50-61. 1925.
ic
Stevens, N. E. Strawberry diseases. U. S. Dept. Agr. Farm. Bull. 1458: 1-10. Aug. 1925.
ig
ANTHRACNOSE CAUSED BY PLC TODISCELLA VE NETA (SPEG.) BURK.
This disease, which has been reported chiefly from sections east of the Mississippi River, is cne of the most important raspberry diseases of the eastern part of the United States. Of the twenty-one states reporting it in 1925, none reported more than usual, while in rere (Cs there was said to be much less, and in West Virginia, Kentucky, and Michigan less than usual. How-
ever, aS will be seen from the loss estimates given in Soli fe, and from the -- 9%
gGuotations followiz the disease. was of ver eee eS importance. ?
269 RASPBERRY — Anthracnose
Table 72. Estimated losses from anthracnose as reported by collaborators,
1925. Percentage: States reporting ::Percentage: States reportin
loss = oe loss :
2h : Arkansas 4. 4 : Minnesota
20 : Pennsylvania 2 225 : New York
16 : Wisconsin, Kansas ats 1 : West Virginia, Illinois, 6 : Lowa, Indiana aus : Michigan, North Dakota 1 : Maryland =e trace. : Virginia
Dates and location of earliest revorted appearance of anthracnose, 1925
May 19 Atlantic New Jersey July 9 Conway New Hampshire June 1 Pennsylvania July 14 Branford Connecticut June 22 Erie New York
Massachusetts: Rarely seen in the last two years. (Osmun & Davis)
Connecticut: Serious on black varieties Eldorado and Plum Farmer. (Clinton) |
New York (Erie County): Considerable anthracnose on purples and blacks was Found. Some fields have as high as 95 per cent infection. Tay lor) Pennsylvania: Bad all over state. Lesions on canes, petioles, leaves, and fruit. We have demonstrated conclusively that it can be con~ troiled by thorough spraying. {Krout)
Arkansas: Very important all over state. Very little attempt at control. (Dept. Plant Path.)
Indiana: Limiting factor in commercial plantings. Delayed dormant spray of lime-sulfur 1-10 controls. Dietz reports disease is being con-— trolled in nurseries by the spray. (Gardner)
Tllinois: Very slight since light infection on canes did not reduce vitality. General, but worse in northern section of the state. Very dry in spring. On black raspberries. (Anderfon & Tehon)
Wisconsin: Major disease, especially in blackcaps. More on red rasp- berry than ever before. Rapid spread to blackcaps eariy in the spring. Killing canes. (Vaughan)
Minnesota: Important with some varieties. Of the red varieties, Sunheam and Ohta apparently very susceptible. A two-acre vlanting of - ime \ Sunbeam ruined by anthracnose. (Div- Plant Path.
Kansas: Twenty to fifty per cent cane infection; up to 100 per cent leaf infection. (White)
270 RASPBERRY - Anthracnose; Crowngall
Oregon: Not a limiting factor on cane fruits in Oregon. Climatic con- ditions apparently unfavorable. Occurs on blackcaps to a very limited extent. oe
According to Baker (1), in the past ten years some states have reported a decrease in acreage as great as 00 per cent, due to anthracnose, while others report annual losses of.25 to 50 per cent of the crop. afihesenly suroemiey veo control disease is by careful and thorough spraying.
Burkholder (2) reports the delayed dormant spray alone if thoroughly ap- plied,will hold the disease in check, provided that spraying is started not later than the spring of the second growing season.
Wilcox (4) discusses the risk of injuring the plants in following the Spray methods ordinarily recommerded at present.
es Oe
Recent literature
1. Baker, C. E. Raspberry anthrecnose and its control. Better Crops A: 10-11, 45. Mar. 1925,
2. Burkholder, C. L- Raspberry anthracnose preventives. American Fruit Grower 45 (4): 16. 1925.
3- Wilcox, R. B. The spraying of black raspberries. American Fruit Grower 45 (2): 4, 20, 23. 1925-
CROWNGALL CAUSED BY BACTERIUM TUMEFACIENS EFS. & TOV
Crowngall was reported to be of slight importance in West Virginia, Massachusetts, and New Mexico, but of considerable importance in Michigan, Minnesota, Iowa, and Washington. Six states reported loss estimates as fol- lows: Michigan, 10 per cent; Iowa, 6 per cent; Pennsylvania and Kansas, 4 Ber cent; Minnesota and New Mexico, 2 per cent.
New York: Crowngall found mostly on La France Lae in Westchester County. (Chupp & Pierstorf£)
Pennsylvania: We are eliminating this disease from new patches by using plants from our rogued plantations. It-is decreasing in Pennsyl- vania. (Krout)
Ohio: At present crovmgalil is not a serious problem of raspberry grow- ers in Ohio. Raspberry plants grown in Ohio seem to be gener- ally free from galls. Where fields are found heavily infested the plants have as a rule been purchased in other states. (Rept. Plant Pathologists, Northern Ohio Exp. Sta.)
Indiana: Mostiy on red raspberry. Found also on purple and black rasp- berry this season. (Gardner)
Michigan: Statewide, but most severe in Berrien County. (Benne tt )
271
RASPBERRY -— Crowngali; Leafcurl
re * . . . * * / Wisconsin; .Major disease in many orchard nurseries. (Vaughan) Minnesota: - About 75 por cent in new planting on soil previously
planted to badly galled rcse bushes. Plants from same stock but
on otier soil he
Washington: The crowngall situ lings have apparently
ation is important. recovered. (Frank)
leafcurl of raspberries was
Caps, but of slight imocrtance in Onio and New Mexico.
only a trace of gall. (Div. Plant Path.)
Badly infected seed-
reported to De serious in Indiana on black- The losses revorted
were: Pennsylvania, 5 per cent; Maryland and Michigan, 4 per cent; North Dakota,
@ per cent; Iowa, trace.
Dates and location of earliest reported senpearance of leafcurl, 1925 June 1 New Castle Pennsylvania June 2A Tndiana June 15 Warrens Wisconsin July 14 Meriden Connecticut New York: Almost all of the berries in the Brandt section of Erie County are aifected with leafcurl. (Taylor) Pennsylvania: Occurs in Pemsyivania only on the reds and purples. It is not of common occurrence. ( Krout) Michigan: Cumberland and Cuthbert only commersial varieties affected. (Bennett) Wisconsin: Practically wiped out on nursery planting stock. (Vaughan)
Minnesota; Minnesota No. 2 apparently quite sub
jeet, 20 per planting.
Marlborough and Cuthbert susceptible.
cent in one Sect. Plant Path.)
The relation of insects to the transmission of raspberry leafcurl is dis- cussed by Smith (1) His conclusions are: } "1. -Aphis ruviphila, Patch, was the only insect carrier
of rasp-
Pennsylvania estimated 60 per cent; New York and Minnesota, 15 per cent;
berry keafcurl a mong several insects used. 2. The aphids must feed upon a diseased plant before be scoming a carrier. 4. The infective agent is not carried over Winter within the egg from the fall gencoration to the spring forms. 4. The invective agent is not inherited by the offspring
in vivipar.cus ‘red raspberries but
repoduction.
W 5 | Ss
5: Ieefeurl transmitted from black to not from red ta black varicties."
(UNDET. )
MOS ATC
s
The losses reported as due to mosaic of raspberry were comparatively high.
Michigen,
RASPESRRY '=.liosaics
12 per cent; Iowa, 8 per cent: Maryland, 2 per cent; and California, “S~per Cente ous
In New Tork, according to Chupp, “Mosaic is the mest seri Ciscase of redcaps."®
The disease was reported to be on the increase in Massechusetts and very impor- tant in Michigan.
Dates and location of carlicest reported anpearance of meseic, 1925
ee me ee ee ee
May 19 Atlantic New Jersey July 2 Grange Connecticut June 1 Grecne County New York July 12 Durham New Hampshire June 1 Pennsylvania
Connecticut: Found on June, Cuthbert (bad), Perfection, St. Regis, Letham, Columbian, and Winfield. (Clinton & Hunt)
Pennsylvania: Columbian probably somewhat resistant. Roguing, which has - been practiced in Pennsylvania Yor three years, has given very good results. We have for distribution this year 200,000 disease-free
plants. (Krout) Now Jersey: Symptoms masked by high temperatures in early summer. (Martin)
Ohio: Ong cf the lim miting factors of groving raspberries in this state (Young)
Wisconsin: Major trouble with red raspberries. Fifty-four nurseries could not be issued general certificat because of infection in Latham and King. (Vaughan)
=>
Minnesota: [Latham generally afi
© Q
ted. Ries y thirty-two certified plant- ings in the state. By roguing, selection, and isolation, the amount of clean propagative sto ck has inerebeeelStepenntaae ee Regis apparently resistant, but they are of minor commercial im— portance. (Sect. Plant Path.)
According to Stakman (2), mosaic is very common on Wild raspberries in northern Minnesota and Canada. The varieties Marlboro, Cuthbert, Redpath, and King are quite susceptible, while Latham is generally infected but yields weil in spite of the disease. Herbert, Sunbdeam, St. Regis, Columbian, Donoborough, Ranere and several others seem to be fairly resistant, especially if not grown near susceptidle varieties.
Wilcox (4) reported that:
"Certain types of raspberry mosaic are masked during not weather Mottled leaves formed curing cool weather retain their mottling, but new leaves developed during hot weather a 7 :
"Rubus innominatus, infected with one type of transmissibie mosaic, was found to be. not only peculiarly smsitive to temperature changes, but recorded these changes by very conspicuous leaf markings. Such in- fected canes, accompanied by a record of their growth during the summer, showed correlation between the Se of seemingly healthy leaves
.and the occurrence of periods of high maximim temperatures. Study of this relationship indicates that for the ae aa of Rubus innominatus the critical temperature is approximetcly 75°F. (24°C.)"
ea RASPBERRY — Streak: Leafspot; SnurSiight
aspberry streak pti jar srom Cenneeticut and Oregon, - From the latter state Zoller reports, "The aiseese is confined to two-plantings of the biackeap variety Curbariand at Gresham;. and causes very slight injury; although hac Percentage “of (infcctian 28 vary High. Strecking on the-canes isimasked at low temperatures. (Joaf iottling appears during cool weather or spring."
w Q,
Recent ee ee
mene ee en ee ee ee ee
ce eon, Poy ts . The relation of insects to the transmission of raspberry learcurl. Jour. Econ. Entom. 18: BOO 5. dune 125s
2.. Shéiman. H.C. Raspberry mosaic. Minnesota Horticulturist 53: 85- 87. 1925.
4-. Wilcox, R. B. Observations on mesking of raspberry mosaic by high temperature. (Abstract) Phytopeth. 16: 80. Jan. 1926.
LEAFSPOT CAUSED BY MYCOSPHAERELLA RUBE ROARK (SEPTOPIA RUBI WEST.)
Leafspot of raspberry was reported from Maine, New York, New Jersey, Tilinois, Towa, -Kansas, and California. In California it caused a loss esti- mated at 6 per cent, while in Iowa, the loss reported was 4 ver cent.
Tilincis; An unusually early outbreak of Leafspot Wa " {llincis,- on May 4. The spots were weli forme
—
noted -at Quincy, a few pycnidia
could be found at that Lime. (H. W. Anderson) Kansas: Important this year. Lesions on cdnes and buds killed on sev-
erely infected canes. ‘The disease caused carly defoliation. (‘Thite) yal
Balioemie:s- Very serious in the state this year. (Milbrath)
Porto Rico: Apparently was brought in on plants from Florida. (Cook)
SPURBLIGHT CAUSED BY MYCOSPHAERELLA RUBINA (PK.) -JAOZ.
Spurblight was reported from New York, Wiscens.in, Minnesota, North Dakota, and Oregon. In Wisconsin, Minnesota, and North Dakota it was one of the most important raspberry diseases. ,
New York: Fairly common but seldom serious. (Chupp & Pierstorff)
Wisconsin: Very gereral. One of the major troubles of red raspberries. (Vaughan)
eva RASPBERRY - Spurblight; Spring frost injury; Other Diseases
Minnesota: In some plantings it was apparently correlated with winter injury. Estimated loss 2 per cent. Ohta generally free. King and Latham usuaily infected, probably less in Latham than in King plantings. (Sect. Plant Path.)
Oregon: Very bad in the Ashland district; some damage following winter injury in the Willamette Valley. It occurs throughout western Oregon, but the only district where it is really serious is the Ashland district of southern Oregon. There is some indication that drouth or other unfavorable weather conditions during the year the canes make their growth favor the development of this fungus the succeeding year. It occurred especially on red rasp- berry, but often on winter-~injured blackcaps. Spraying with Bordeaux 4-43-70 when canes are from A to & inches high, 15 to 18 inch inches, and 36 inches, has given rather satisfactory results, al- though the first two applications are all that are really neces- sary. Cuthbert is the only variety grown commercially. (Zeller)
SPRING FROST INJURY
The losses reported as a result of frost injury this year were as fol- lows: Minnesota, 40 per cent; Michigan, 10 per cent; Iowa, 6 per cent; Maryland, h per cent.
Wisconsin: Frost injury found even on the so-called winter~proof Latham. (Vaughan)
Minnesota: Latham, which is ordinarily winter-hard; badly affected, es- pecially on low rich soil. Sunbeam and Ohta apparently are winter- hardy. (Div. Plant Path.)
South Dakota: Although there was much damage to other fruits the rasp- berry escaped. (Evans)
OTHER DISEASES AND INJURIES
Armillaria mellea (Vahl.) Quel., rootrot, Washington. (Frank)
Ascospora ruborum (Oud.) Zeller (5), leafspot, reported from Washington and Oregon. Zeller stated that, "This is the commonest fungus in western Oregon but it is questionable how much damage it does. It prevents winter-injured plants from recovering when they might otherwise produce a good crop."
Botrytis sp-, gray mold rot, Connecticut (one report), New York (seen oc- casionally), and Washington. In Washington it was probably the cause of blight of the newly formed fruit according to Arthur Frank.
Cercospora sp-, leafspot, Florida. tk eg
Gymnoconia interstitialis (Schl.} Lagh., orange rust, Michigan and Wis- consin. See blackberry.
-RASPBERRY - Other Diseases 279 BLACKBERRY — Orange rust
Phragmidium imitans Arth., leaf rust, Washington, Oregon. According. to Zeller of Oregon, “This rust is very prevalent this year causing the usual leaf lesion but the serious phase of the disease is the cane lesion produced at the base Causing a brittleness." In Washington it is prevalent in the Puget Sound regione ? :
- Phyllosticta sp., leafspot, Florida. sphaerotheca humili (pc.) Burr., A powdery mildew, probably this species, was reported from Oregon. According to Zeller it is limited to the Munger var-— icty, on which it is very serious, affecting canes as well as leaves. sn unac- termined powdery mildew occurred on red varieties in Indiana.
Wee aetiice elhocabram Reinke G@ Berth., bluestem, wilt (4, 6, 7]. Very destructive on black raspberrics in New York, according to Chupp and Pierstorff. Also reported from Ohio and Washington.
| Bacterial blight (undet.) reported from Washington causing a twig blight on the variety Antwerp. (Frank) | |
Recent Literature on raspberry diseases
1. Atwood, G. G. Raspberry diseases and control measures. Circ. Dept. Farms & Markets; New York 280: ll p. 1925.
2. Colby, A. S. The raspberry disease situation in Illinois. News Letter Illinois State Hort. S38. 1925 (4). May 10, 1925.
5- Frank, A. 192A information on winter. injury, mosaic and other dis- eases of raspberries in western Washington. Proc. Washington tate Hort. Assoc. 2: 126-135. 1925.
A. Harris, R. V. The dlue stripe wilt of the raspberry. Jour. Pomol. & Hore. OGL. As 22teeegn sune 1925. |
5. Zeller, S. M. Coryneum ruborum Oud. and its ascogenous stage. Mycologia 17: 54-Al. Jan.-Feb. 1925.
6. bate OL A case of Verticillium wilt (blue stem) (V. alboatrum)
lack raspberry in Oregon. (Abstract) Phytopath. 15: 125-126.
7+ Gandel, G. Le Why raspberries "run out". West. Fruit Y CAD Ss Fa apote .1Y25-
BLACKBERRY
ORANGE RUST CAUSED BY GYMNOCONIA INTERSTITIALIS (SCHL.) LAGH. AND KUNKELIA NITENS (SCHW.) ARTH.
Of the 17 states reporting on orange rust of blackberry not one indicated gfeeter prevalence of this disease than last year or in normal years. arkansas Yetorted it to be very important and in Wisconsin it was the major disease.
27 BLACKBERRY ~ Orange rust; Anthracnose; Other Discases
Table 75. Estimated losses from orange rust as reported by collaborators,
1925. : Percentage: States reporting ::Porcentage: States reportin loss__: Eee SSE a 3 Arkansas, Iowa ih Se 5 : Pennsylvania 4 re : Michigan of trace : New York ‘ y : West Virginia,Maryland : |
Dates and location of earliest reported appearance of orange rust, 1925
April 11 Calhoun South Carolina June 8 Greene County New Jersey April 12 Raleigh North Carolina June 21 Plymouth Connecticut April 15 Middlesex Pennsylvania July 6 Hillsboro New Hampshire May 7 Orange County Indiana
Pennsylvania: This discase is not very common on the blackberry where the patch is well cared for. (Krout)
Florida: Very severe on blackberries in this state. (Dept. Plant Path.)
Michigan: More destructive on black raspberry than on blackberry. (Bennett)
Wisconsin: Major importance this year. Noted considerable on red rasp-
berries in La Crosse and Washakie Counties. Came late, after September 1. (Vaughan)
ANTHRACNOSE CAUSED BY PLECTODISCELLA VENETA (SPEG.) BURK. Anthracnose of blackberry was of slight importance in 1925 according to the reports submitted. Arkansas and Iowa reported losses of 1 per cent.
Pennsylvania: Only a trace (less than one-cigth of 1 per cent) of this disease can be found on plantations well cared for. (Krout)
Florida: Well distributed over the state and is doing considerable dam— age. (Dept. Plant Path.)
Oklahoma: Causing considerable loss especially in plantations where the
plants were weakened by adverse weather and soil conditions. (Rolfs)
OTHER DISEASES AND INJURIES
_ Bacterium tumefacicns EFS. & Town., crowmgall, New York (on wild black- berry}; Florida, Washington.
25 | By BLACKBERRY & Other’ Diseases (( DEWBERRY — Diseases
Botrytis fruit rot, Massachusctts. "Rotting of ripened berrics common with considerable damage. A Botrytis is most frequently isolated but Rhizopus and Penicillium also present." (Davis) —
CcphaleuroS: virescens Kze., algal leafspot, Florida.
See rubi Sacc., pioeen, Florida, Louisiana (common).
Fusisporium 1 rubi Wint., double blossom, Delaware, Florida. According to Adams of Delaware, this is i first infection observed in a commercial planting in Delaware. In Florida it was reported sevcral times from various sections of EAC state doing considerable damage. .
' Mycosphacrella mbi Roark, leafspot, reported from New Jersey (not impor- tant), Florida (occasional), Louisiana (common), Texas (prevalent), Indiana ec), and Towa Oop
Canker (undet.) An undetermined canker associated with Coryneum and Phomopsis was observed in Washington.
Dwarf disease (viras), reported from Oregon by Zeller (1), "Causes dwarf- ing of canes and stubbiness of onds of canes similar to streak, but no streaking of canes. As far as know, this discasce occurs only on the Pacific coast. The most susceptible host is Phenomenal blackberry, which should not be planted. Have never seen a planting of this varicty, or one containing this variety, that did not have some dwarf. Transmitted to loganberries wherever they are planted With Phenomenal."
Frost injury, Michigan reported 43 per cent loss. In Wisconsin frost in- Jury was a major trouble while in Illinois, according to Anderson, blackberrics cre Gamagcd more seriously by the frost of May 24, than were raspberrics.
Mosaic (undct.) A mottled appearance of leaves observed at Middlesex, New Jersey, “August 16.
Reeent Llitcrature on blackberry diseases
ier eek LOP, S. M. Some facts about loganberry "dwarf". (Abstract) Phycopachs 15: -125.)) Bebe 1925. |
EWBERRY —
Anthracnose caused by Plicctodiscella veneta (Speg.) Burk. was reported from New York and South Carolina. According to Fenner of South Carolina, “Anthracnose was important but not serious. It occurred in local areas of the sand Hill and Coastal Plain regions, wherever the crop was grown. New growth _. became infected from old canes which remained uncut. Bordeaux sprays have con-~ trolled the discase."
Dutton (1) recommends, as a result of three years! experiments on the control of dewberry anthracnose, a dclayed dormant application of lime-sulfur 5-100 with the addition of one pound of calcium caSeinate, to be followed about a week before blooming by an application of Bordeaux mitture An 100.
Leafspot caused by Mycosphaerella. rubi Roark, Delaware (generally preva— lent. in commercial ee a Orange rust caused by Gymnoconia interstitialis (Schl. ) Lagh., reported Prom Dutchess County, New York. ; ? oa Shee
278 LOG ee TO CURRANT:
Recent literature on dewberry diseases
1. Dutton, W. C. Spraying dewberries for anthracnose. Mich. Sta.- 5 Spec. Bule 144: 4-13- 1925-
2. Matthews, C. D. Dewberry growing. Amer. Fruit Grow. Mag. 45 (6): 5, 14-15. June 1925. Two most serious troubles are anthracnose and double blossom.
Anthracnose caused by Plectodiscella veneta (Spveg.) Burk. was reported from Washington.
Crowngall caused by Bacterium tumefaciens EFS. & Town. was reported from Washington.
Dwarf (virus) (1) was reported by Zeller from western Oregon, "Keeping out Phenomenal biackberry, which is always affected, and roguing give effective control. Quite common but can probably be controlled."
leafspot caused by Mycosphaerella rubi Roark. According to Zeller, this leafs spo of is very common in Oregon, but is “easily controlled by Bordeaux sprays.
Mosaic (undet.) was reported from Washington.
cee eee caused by Mycosphaerella rubina (Pk.) Jacq., leafspot, Oregon
(limited to winter injured plants causing what at the growers call gray bark).
VEX
Winter injury. Regarding winter injury in Oregon 5. M. Zeller of Oregon
"In the Willamette. Valley about 60 per cent of the canes were killed outrignt and the 40 per cent remaining had a very favorable spring with r and intermitt ent rainfall until the second or third week in er, this favorable weather was conducive to the production at surface and a large set of fruit on fruiting canes and an e growth, thus with the hot weather late in June, r cent loss in the berries set was brought about “The partially winter injured canes could not supply e to the developing fruits which died before maturity. ially ripe berries were sunburned."
Recent literature
1. Zeller, S. M. Some fects about loganberry "dwarf". (Abstract) athe: 15: 1260, «A925.
rd +e) eal Ch w O a)
CURRANT
Leafspot caused by Mycosphaerella grossulariae (Fr.) Lind., New York (statewide, less than usual)- -. Anthracnose caused by Pseudopeziza ribis Kleb., New Jersey (unimportant), Oregon (general with host).
CURRANT TO CRANBERRY
Rust caused by _Puccinia grossulariae (Schun.) Lagh., Winnepeg, Canada.
Blister rust caused by Cromer tum ribicols Fisch., (See white iy bene Supplement A
Powdery re caused by Sphasrotheca ‘mors-uvae (Schw.) Burk. & Curt., Washington arid Manitoba, Canada (rather injurious this year).
Scald (high temperature), New York. |
Reversion discase (unmdet.) An interesting article by A+ H. Lees on means of infection with the reversion disease of black currants appeared (2).
. eae
1. Anon. Reversion disease of black currants. Big bud. Fruit, Flower and Veg. Trades. Journ. 47: 670-671, June.1925.
2. lees, A. H. Reversion disease of black currants: Means of infection. Ann. Appl. Biol. 12: 199-210. May 1925.
GOOSEBERRY
Anthracnose caused by Psuedopeziza ribis Kleb., was reported from New Jersey, Indiana, and Oregon. -In ‘the Willamette Valley of Oregon, according to Barss, much more than normal was reported and a loss of 10 per cent was estimated. Serious defoliation occurred in many cases, with resulting damage to the vitality of the bushes which will probably affect next year's crop.
Powdery mildew caused by Sphaerotheca mors-uvae (Schw.) Berk. & Curt., Wisconsin, Washington, Oregon.
Rust caused by Puccinia grossulariae beeen) sites was reported to have caused a 2 per cent loss in Iowa.
Die~back, Botrytis sp., Washington.
=
Recent literature
Le Colby, A- S.- Control of the leafspots on gooseberries. Amer. Fruit Grow. Mag. 45 (7): 24. 1925.
2. Dietrich, G. Bekémpfung des amerikanischen Stachelbeermehltaues. (eertre 1 of American gooseberry mildew). Deut. Obst- u. Gemuseb.- Zeit. 71: 80-81. Feb. 13, 1925.
3. Hahn. Die Winterbehandlung des Stachelbeermehltaues. (The dormant tréatment of gooseberry mildew). Gartenw.. 29: 188-190. 1925.
CRANBERRY
Bli ht, ‘more of this trouble occurred in Wisconsin this year than usual, aecording to S. B. Fracker. He reported that seventy-five per cent of fruit stopped development at pin-head size.
250 CRANBERRY
Faise blossom, According to Stevens (4) observations on false blossom of cranberry seem to indicate that this trouble is infectious. It-is thought that false blossom was not due entirely to poor cultural conditions because it of%en occurs in well-drained and well-cultivated.bogs. The author suggests that unti the cause of the disease has been definite’ determined it is unwise to plant vines from bogs where the disease occurs. According to S. B. Fracker, this disease Seems to be increasing slowly in Wisconsin where it was slignatly more prevalent than usual. Aside from the frost this is considered a major trouble in cranberry production in that state. Apparently a temporary improvement is induced by hold-— ing winter flood until July 1. It was found on A8 of 61 marshes examined, and for the first time in history in three wild bors.
— -
Cranberry Diseases in Washington and Oregon
The following report was submitted on cranberry diseases in Washington and Oregon in 1925 by H. F. Bain: of the Office of Fruit Disease Investigations, United States Department of Agriculture:
"The 1925 cranberry crop in the,Pacific Coast region was the largest on record, chiefly due to the uniformly good yicld on most of the Wash ing- ton bogs. As in past years, very little field loss was caused by fungi Hard-rot or cotton-ball, caused by Sclerotinia oxycocci Wor., was preacite in a few ecied but on the whole this discase was less abundant than usual. Such vine diseases as rose-bloom (Exobasidium oxycocci Rost. y3 red. leaf- nit (Fck1.) Wor.) and black stem spot “(eaused ue an -undes-
vere also less abundant than in an average yea
"The Derries kept well in storage, in contrast to the experiences of some year The usual species of fungi. were found in culture made from berries which rotted in storage. In a series of 750 such quleunesy the end-rot organism ( Busines cum putrefaciens Shear) developed in 63 pee
cher fungi eben occurred less frequently were Botryt joo rtis a Junata Shear, Sporonema oxycocci Shear, and Sporonema pulvinatum Shear."
Discase Control by Airplane Dusting
An interesting powa ieee in the movie rod of cranberry diseascs by dust— ing from airplanes has been reported (Ue: Ss Dept. Agr. Official Re cord A (51): 6. Dec. 24, 1925}. | }
"The airplane dusting of cranberry bogs undertaken at Pemberton, New
Jerscy, during the annual meeting of the American Cranberry Growers'Associ- ation, August oe 1925, was little more than-a demonstration of the-practi-
_cability of so handling an airplane as to give satisfactory distribution of the dust on cranberries.
"That copper limc dust will greatly reduce the fruit rots of cran-
berrics has been proven by three years! work with hand dusting machines in Massachusetts. The airplane apparatus at Pemberton indicated that a fairly satisfactory application of dust may be obtained by airplanc.
"If practicable, airplane dusting offers certain advantages in ad- dition to the speed of the operation over any other known means of apply-— ing fungicides to cranberry bogs. In cultivated bogs the cranberry vines
cover the ground completely like the grass in a well-kept yard. spraying or dusting operations necessitate a certain amount of trampling
281 CRANBERRY TO MULBERRY
Which is generally believed to be injurious.
"One difficulty encountered in arranging for the demonstration at
Pemberton was to find a bog having a satisfactory landing place near by. Few cranberry bogs are located near large open ficlds. Most large bogs have, however, good-sized reservoirs or ponds near by, and it has been
suggested that a hydroplane should be used for dusting cranberry bogs."
Recent literature on cranberry diseases ..
ae
2
5.
Anon. <Acroplanec wins friends among cranberry growers. New Jersey femieulture 7 (10)+ 13, 15. Oct. 192. }
Beckwith, C. S. Cranberry disease work in New Jersey. Proc. Amer. Guenberry Grows Assets 95g debe L925.
Morse, S. F. Airplane dusting for cranberry pest control. Proc. Amer. Cranberry Grow. Assoc. 56: 4-5, 8. 1925.
Stevens, Neil E. Field observations on false blossom of the culti- vated cranberry. Phytopath. 15: 85-91. 1925.
Notes on Rlueberry and cranberry disenses. Proc.
fer. Crenbeorry Grewers Assoc..55: 7, 10. 1925.
BLUEBERRY
ss Leafs pot caused by Phyllosticta sp., reported from Palm Beach County, Florida, July 7.
Stem rust caused. by Calyptospora columnaris (Alb. & Schw.) Kuehn was re-
ported from Minnesota where it is said to be fairly common in the northeastern part of the state.
Recent litcrature
ee
Stevens, Ncil EB. Notes on blueberry and cranberry discases. Proc. Amer. Cranberry Growers Assoc. 55: 7, 10. 1925.
MU LBERRY
)
Ordinary.
1
Texas rootrat caused by Ozorium omnivorum Shear was reported as prevalent | on mulberries growing in the black lands of Texas.
Popcorn disease caused by Sclerotinia carunculoides Sisler & Jenkins was
reported with specimens from Telfair County, Georgia, by 0. C. Boyd and from Alabama by W. L. Blain.
CITRUS FRUITS -— Citrus canker; Citrus blast; Melanose
SUR-TROPIGAL PRL?
a
Oo
t- A 13 fe 4]
a
=)
' aj
< zn
ee ee
Prepared by H. R. Fulton
Diseases Gaused by or Attributed to Parasites
CITRUS CANKER CAUSED BY BACTERIUM CITRI (HASSE) JEHIE
~
district of Louisiana’ (Bde ext ered Mareh, 1925, at Rca, in Alabama or
Citrus canker was _repor ted to be common on oranges in ee Bayou Lafourche \ Sis
- .In Florida five infected trees were discov—
ney Were all de spe No canker was observed Texas, according to collaborators.
CITRUS BLAST CA USED BY BACTERIUM CITRAREPACIENS
PSEUROM ons CITRIPUTEALS )
'
Lek
California: - Prevalencé.'about,
oe) GOL
the same as usual; causes death of leaves, areas surrounding lee f scars, and of seme twigs; occurs in orthern California; usually anak in March and April; sweet
range susceptible, lemon a little less so. (Fawcett)
MELANOSE CAUSED EY PHOMOPSIS CITRI FANCETT
=
Meianose was LS se to be a reemit, but unimnortent in Alabama and
Louisiana. The following .reports were ireceived from Florida and Arizona.
Florida: Severe this Seasen as a rosult of
considerable rain occurring betere ‘tie 22
ruit reached the immune state. Excellent control > 5 . - \ was secured with Bordsaux-oil emulsion. (Rhoeds!
Less severe than usual. About 75 per cent of the citrus oy
plantings’ moreor less severely infested. One application of
' Bordeaux-o0il emulsion made, in late April or early May gives good control. (Winston)
+f Arizona: On leaves of sweet seedling orange, Pima County. first report from state. (Streets)
Vote t See &:RRA CA. P. S02. |
Probably
ne) Oo A
CETRUS FRUITS — Stem end; Senb; Blue mold rot
CITRUS STEM END ROT CAUSED BY PHOMOPSIS CITRI YAVCETT AND DIPLODTA NATALENSIS EV. AND OTHSR FUNGI |
In Alabama and Louisiana stem end rot was said to be of slight importance.
Other reports received are as follows:
Florida: About as prevalent as usual. (Rhoads) More than usual. More prevalent in groves during the fall than has been the case since 1918. (Winston)
California: Stem end rot caused by Diplodia sp. and by Dothiorella ribis was of ion importance in long storage of fruit from coastal section Phomopsis californica was less prevalent than last year, and was es obably of minor importance, except on storage lemons.
Porto Rico: Common, causing losses in shipment. (Cook & Tucker)
‘CITRUS SCAB CAUSED BY SPHACELOMA SP. (S. FAWCETTI JENKINS; SPOROTRICHUM CITRI BUTLER)
Florida: More severe than usual in some sections when weather conditions favored development. (Rhoads)
About the same as usual, of major importance in low damp situ- ations. About 75 per cent of grapefruit plantings more or less infested. A late dormant avplication of Bordeaux-oil emulsion gives better control than any other time. (Winston)
Alabama: as usual; controlled by spraying. (Miles & Blain) ious on nese oranges where not controlled by Bordeaux mixture applied to the very young fruit, beginning with petal drop,
(@)
Sam Ser
Louisiana: Common in satsuma oranges, as usual. (Edgerton) Texas: Unimportant, traces. (Tau benhaus }
Porto Rico: Abundant, the most important citrus disease on the island; good results from use of Bordeaux mixture. (Cook & Tucker)
BLUE MOLD AND GREEN MOLD ROTS CAUSED BY PENICILLIUM ITALICUM WEHMER AND
P. DIGITATUM (FR.) SACC.
Penicillium rot was reported by Fulton to be of very slight importance
in Alabama, while Cook and Tucker ssid that it was common in Porto Rico. Re= ports from Florida and Califomia are as follows:
CITRUS. FRUITS - Blue mold rot; Anthracnose; Footrot
Florida: This form of decay is far more prevalent Than In TeCeny Veume. eBSoe ;clably during Ths, Pali era ecard y Wimiceds. exoessive rains ag- é seems that the fiult was un-
BrTaVALeG, Ue mie (serie neue ti also. ax has not given das much control as Was ex—
usually, bengler. ene \
pected. (Winston)
Both types of rot common everywhere; oo wash has effec-
Walizornias sini tively controlled the common green mold (7. digitatum) but has not boen entirely successful against tae blue contact mold (P.
italicun). (Pewoott)
IENTTP ATTRIBUTED TO GULTETOTRIGHUM
ANTHRACNOSE AND CITRUS WETRERTTt | : GLOBOSP Cas Lal! DES. PEA tea | | >
Anthracnose Was reported to. be of minor AMOK LANGC « Besides the statc- ments quoted below, reports were received from ‘Louisiana, Texas, and Porto Rico, Tucke Ye
Where it is-sometimes sovere, according to Cook and
Florida: ‘Usual occurrence; of minor importance; probably not a realiaie= ease, bub a manifestation following root drowming, starwou om, frostuinjury, drowth » ete. Giana
Gommon and widespread through out state but no more severe than ex
diseases. ‘Withertip is tne Tine
the citrus Section of ane and. cannot be considered major
é —- 4
S¢ x develop most abundantly on trees, whose viruality has becn oatly reduecd for any reason, es-= pecially from drougnat. Ne a te eauscd some damage to fruit
locally. (Rhoads) Alabama: Not important. (Mi Lin asyswow frail ° | (Fu ton) 7 a
ina) aS ee ie satsuma oranges in long storage.
California: Usually a minor tr: ‘e characterized by spotting or slow
rotting of fruits. (Feawee. )
FOOTROT ATTRIBUTED TO PHYDHTHORA TERRESTRIS SHERB,
Florida: Usual prevalence; banking with clay to induce root formation 6iven goodl results in. one: in-
uu eam girdled base scems to have
a stanec. (Rhoads)
Or nce importance on secdling orange and grapelruit, trees; sweet orange, rough lemon, grapefruit and sour orange stocks are in the order given; aeration of the crown
increasingly resistant gives good results, especiaily when roots are painted with a
bluestone paste. (Winston)
Texas: Same as usual; only a few trees affected and progress of the dis- ease is slow; cleaning and painting with Bordeaux successful.
(Alsmeyer )
285
CITRUS FRUITS ~ Fruit. rots; Gummosis
FRUIT ROTS CAUSED BY VARIOUS ORGANISMS
Black rot caused by Alternaria citri Pierce, Florida, "Of occasional oc-— Currence usually as blossom end ro%." " (Fulton); Alabama, "On satsuma oranges in long storage." (Fulton); California, “Hard, crn decay at stylar end of oranges, especially Washington Navels, was more prevalent than usual, and fairly impor- tant although only a small percent of all oranges involved; Alternaria rot of lemons was about the same as usual, and was important in stock held in iong storage." (Fawcett)
Brown rot caused by Pythiacystis citrophthora EH. H. & R. E. Sm., Californ "Occurrence was less than usual, associated with less than normal moisture durin season of greatest prevalence, from November to February; lemons are most suscep-— tible, followed by oranges; controlled by spraying the ground and lower branches with 4~4-50 Bordeaux mixture." (Fawcett) .
Grey mold rot caused by Botrytis cinerea Pers., Galiforia, "Occurred principally on lemon fruit, and was less prevalent than usual. (Fawcett)
oclerotinia rot caused by Sclerotinia sclerotiorum (Tib.)} Mass., alifor= nia, "Less prevalent than usual, attributeble to. loss than-norma’l. olskure ; at— tacks -tetions prinéipally in storage." (Fawcett)
Fusarium rot caused by Fusarium spp., Florida, "Of minor importance usu- aily as a form of blossom-end rot of oO oranges."(Fulton); Alabama, "Of minor im- portance as a cause of decay in long storage."(Fulton); California, "A:minor de- cay of citrus fruits, firm to soft and pliable." (F Fawcett) ia
Qospora rot caused by Oospora citri-aurantii ©. 0. Sm., pee a than usual; follows insect puncturing of mature fruit in wet weathe " (Folt California, "A sour, watery storage rot of lemons, of minor Pie ee: beca isan of less long storage." (Fawcett)
Aspergillus rot caused by Aspe rei Llus | niger Tiegh. was reported from Florida and California; of minor importance, favored by high temperature.
Trichoderma rot caused by Trichoderma lignorum (Tode) Harz, California, "A minor decay of citrus fruits, leathery and chocolate brown." (Fawcett)
GUMMOSIS DUE TO VARIOUS ORGANISMS
DR ye
Pythiacystis gummosis: caused by Pythiacystis citrophthora EH. H. & R. HE. om., California, ieee eh than - usual, moisture being less than normal; causes death of bark on trunk and roots and is coextensive with citrus plantings; greatest. injury in spring and summer; lemon, sweet orange ae ereper tues stocks SUScepti- ble; ig ate and sour orange stocks resistant." (Fawcett)
Botrytis gummosis caused by Botrytis cinerea Pers., California, "Was of minor Chane being less than normal, the season being relatively dry; preva- demt in the moister coastal regions; causes death of bark on trunk of lemons." (Fawcett } i | Diplodia gummosis caused by Diplodia sp., California, "Occurs mostly * On lemon in moister coastal sections causing death of local areas of bark and wood." (Fawcett) » a
‘Dothiorella gummosis caused by Dothiorella ribis (Fekl.) Sacc., Ca lifornic, wa newly recognized discase causing death of areas of bark with formation of. gum pockets on lemon trunks in moister coastal sections; lemons are most susceptible.
Fawcett) |
ed
Ui & o) oF) | e)
4
S (olay
VU
v
'
BS)
rnica Fawc., € i
Non-—Parasitic
iS GI
rite
diseases;
a
Uy Li Ui
i a a aehoSee ad i Ak } i | ) : AN US DLA, L
~ Uu
FR. 4
286
oC
+ —
eee
}
EASES
oads e w
commune Fr. Z = =
tly on dea
of footrot lesions at the
ais
i
zophy! lu fot. (Rh
(Vahl) Quel., C O}
~
>
& Del 4
t
BR PARASITIC D
A
tT +
less frequen
Sch L Di
~
liea
0
,
me
is
at iJ 2
it wood r}4
aeaa
>
ro au} = ee W) UW bs. tS Hes nN YD wo EN Qg -»s re (ese Hh oS 42 +3 rf pee) O fy acy oO | i Ftp Ww +4 ‘yc te | © hi Ww Omi rel red fey cad) Ce oo | e W Py, oO ca u) ic) fa 3] > cll of &4 a) ra] © si] 42 | «rt ‘Ol E 4 C_) Sp aot ri rl jon} 1a) Cl] a) tn) Oy) v Ci wo a ~ Oy Ot Ry ret ics Om) hee oan) Py Ae a) Oleg Oo} a op) rt (@) +a iis S
icO.«
ns Kunze, n Porto R
orchards -1
Guros Viresce
to a few localities and most preva!
a ey Ve
= 1 ; ih
Wi ilG it
anh Or T ae, FF.tmit sJs-lick UGA
yt
ae ee aa
Ce
’ wz
yom ow, Scalbavyilwt ¥
CO
v) j Set £3 C-™ TH of oO w @
fy Oh Pat
+ rn
=
—
S oat i
QO, By © os 2 hiss | m Op ae = filed cS wf OO a Ug e a : G4 P= " ria] rt . e es of fd a) re oa] 1 oD) A. el x 4 ved ou 4° ee wy (ible) ie) Mw & & rl C4 oO ate fy eof (eo) 42 op) ~ ret) GQ) ae (= 43 | ee = n 2 a | be oOo o as Md w | oO rl Oo ® 49 r4 — WD] ” =| ap 80 © : ® & ert rat Grd oO ie) wo -~ O Pp» OQ ed rm Gg cad Ww wo +) 5 poate 2 . oi ai © of OLY oF GS WO edihe 4D) ”) © rt wl] e S| ee) eo: | ie) ine} er] O O + fed & = Sate (al a QO, oO] Oo B ff © Y > s o wo ¢ o| c, 2 cS rhe! rel ) nl wy 4) Hi W) ES “fe { sar, nN Y. © | e lca fay seed QO 44 wi ® 45 ey ee eieloy, +4 wo F YG o ht { ine) cal ® wo S45 an ft Gal
™e
Oo Wr ett fe Cabo | oP fly fey} Sa) ‘ ae 1 os w re] é ay ark yy co) b Oo (ch fy ) ja CO) Sat oO
-*
MN cccurrence.*
TIO
FA. iz ~
Us
4 en
7A qu
Y
=
+
mh ai
hey ar (OW fre
_*
- 2
eo Né va)
4 UNE "©
Was reported of!
eS,
mes wherever edg
H
3
ens:
unting oO
UL
nornless 1 i
is tumefaci
aused s
— se vY \ i 4 nscon
a: ray o ?
\
jo Sp a | ae
u yntro
LY e > -
Bo. good ¢:
h Wa Pa ~ . em ives
— «0 AD
CITRUS FRUITS - Non-Parasitic diseases
Frenching or Lime chlorosis was reported by Rhoads as being common and Widely distributed in Florida. Winston reports less than usual and of minor importance; humus corrects the trouble. In California there is manifested a uniform yellowing of leaves where there is a calcareous substratum which prob- ably bringsabout an iron deficiency. (Fawcett)
Mottle leaf was probably less than usual in California; investigations indicate a probable inability of the tree to satisfy its calcium requirements when the soil reaction is too alkaline. (Fawcett).
Gummosis (undet.) was reported by Rhoads as being widespread and fre- Quently quite destructive, with tangerine trees appearing to be particularly susceptible in Florida. Winston reports it to he about the same as usual, of minor importance in Florida, and says that caustic disinfectant washes fre- quently cure the disease. Cook reports the disease as being severe sometimes in Porto Rico, and recommends treatment with carbolineum.
Psorosis (undet.) was reported by Rhoads and by Winston to be about the Same as usual in Florida. Winston stated that it is of minor importance, and that caustic disinfectant paints or washes apparently cure the disease. Cali- fornia, "About the same as usual, affecting bark and wood of trunk and large limbs; coextensive with sweet oranges in the state, and the most importent dis- ease; grapefruit and occasionally tangerines are also affected; scraping method of treatment successful." (Fawcett) |
Blight (apparently non-par.) was reported by Rhoads to be less common than formerly in Florida. It occurs most frequently on soils more or less Closely underlaid by a coquina rock, less commonly on soils with a clay subsoil. Usually it is caused by a deficiency in the supply of available soil moisture during the dry season of the year, but often by excessive soil moisture for long periods in poorly drained situations with resultant death of roots. Winstor reports it to be of minor importance in Florida except in a few localities where it is killing quite a few trees.
Peteca (cause uncertain) was of minor importance in California, being probably less than usual; it occurred in winter on lemon fruits producing char- acteristic sunken spots or pits in the rind. (Fawcett)
Endoxerosis (Internal decline) attributed to water relation in part, was fairly important in California, Cane anG internal drying and browning of fruit of ae only. (Fawcett)
ruit splitting (non-par.) about the same as usual in Florida; usually Fae When heavy rains follow a period of drought in late summer or fall. (Rhoads)
Frost injury was not recomed from Florida, Alabama, or Louisiana. Ac- cording to Alsmayer, of Texas, the fruit was frozen on the trees the last week in December 1925, in Hidalgo and Cameron Counties, and the trees were moderately damaged.
Lightning injury. Several cases were reported in Florida, according to Rhoads. Winston reports more than usual in Florida, causing minor damage.
Recent litereture -on various citrus diseases
1. Barger, W. F. Treating oranges with borax solution for control of blue and green mold. California Citrograph 10: 149. 1925.
2. and L. A. Hawkins. Borax as disinfectant for citmris fruit. Citrus Indust. 6 (9): 8-9, 24. 1925.
288
10.
ae Be te.
14.
ql.
iG
16.
17.
CITRUS FRUITS = Miscellaneous diterature
“ger, W. Rey and” i. A Hawkins. Borax as a reat cient, for citrus iruit. Jour. Agric. Res. 3: _169- 192." -1925.
saintiteieinda: He “pe Revort on internal decline (cite eel es of Lem- ons. California Citrograph 10: e274, 294, 305. 1925.
Blanchard, V. F. ‘Treatment of frost injured. feed and. fruit. Cali- fornia Citrograph 10: “eA, 180-182. Mar. yee
Bragdon, K. Ee Spray with Bo rdeaux- ond tor senen of melanose. Florida Grow. 42 (10): 15. sept. 5, 1925. hie
Carne, W. M. Blue mold on oranges. Jour. Dept. Agr. Western Aus-— tralia II, 2: 206+292. 1925. a ter, Citrus brow rot. Jour. Dept. Agr. Western Australia
Citrus diseases. Brown rot and leaf blight. Jour. Dept. Agr. Western Australia II, 1: 519-522. Dec. 1924.
Doidge, E. M. Brown rot in citrus fruits (Pythiacystis citrophthora R. and BE. Smith.) Jour. Ree Agr. South Africa 10: 499-503. June 1925. | Pian 3 )
Fawcett, H. S. epee a Gee on bark diseases of citrus trees in sicily. Phytopath. 15: Al-4e.- pee (1925. :
Bark diseases of citrus trees in California. lair
fornia Agr. Exp. Sta. Bull. 395: ‘161. Oct. Ba
The decay of citrus Pouded. on arrival and in storage at eastern markets» — ca Citrograph 10: 79, oe GC Gas
1925.
Fulton, H. Re and J. J. Bowman. Preliminary results with the borax treatment of citrus fruits for the prevention of blue mold rot. Citrus Indust. 6 (3): 20; 30, 32, 34. Mar. 1925.
Relative susceptibility of citrus Opariioe sees attack by Gloeosporium limetticolum (Clausen). Jour. Agric. Res. 30:
629-635. 1925.
Hddawoni: Re W. Citrus trunk and ‘root disease es a Grower 45 (2): 5, AA-A5 1925. ; es
Jenkins, Anna E. The citrus scab fungus. Phytopath. 15: 99-104. 1925)
Kamat, M. N. Gummosis of citrus treess Poona Agr. Coll. Mag. 17: 86.88. Sept. 1925.
CITRUS FRUITS — Miscellaneous Literature FIG
19. Kater, .J« Ms Morphology and life his tory of Polytomella citri sp. nov. Biol. Bull. #9: 213-236. Sept. 1925.
cQ. Katzprowsky, S. Formaldchyde gas, a possible control of decay in lemons. California Citrograph 10: 254. May 1925.
21. Kay, A. 0. Soil moisture studies in relation to diseased tree con- ditions in Brevard County. Citrus Indust. 6 (8); 5-9, 22—25.
1925.
22. Lambert, M. BE. The present status of the citrus seab fungus - 2 recent discovery. Citrus Indust. 6(4): TEL es) AOR ie) Shean
23. lee, H. A. The comparative resistance to footrot of various citrus species as root stocks. Philipp. Jour. Sci. 27; 2A3-254. June Giaige
el. lLewcock, H. K. A citrus bacteriosis occurring in South Australia. (Abstract) Phytopath. 16: 80. Jan. 1926.
2). Smith, J. L. Safeguarding Satsumas from damage by cold waves. florida Grower 42 (11): 7. 1925.
26. Stevens, Neli E. and Marguerite S. Wilsos. The citrus stem—end rot "Diplodia;" its life history and relation to Sphaeropsis malorum. Phytopath. 15: 442-540. 1925. .
eis Webver,.H. J. A comparative study of the citrus industry of South Africa. Bul. Dept. Agr. South Africa 1925 ¢46): 1-106. 1925.
26. Wickens, G. W. Exanthema of citrus trees. Rep. Proc. Imp. Bou,
Conf. London 192A; S535 7% 1925.
ej*s ~Winston, J..Ri, J. J» Bowman, and W..J. Bach.. Relative suscepti- bility of some rutacecous plants to attack by the citrus-scab fun- gus. Jour. Agr. Res. 40; 1087-1093. 1925.
Soe-uNanston, J. a Control me lanose and thereby prevent “ammoniation." Cris Tadust, o (ae 9, 4G, Al. Aer. 1925.
Soi Commercial control of citrus metanose in Fiocrida in
oe
1923. Proc. Florida State Hort. Soc. 37 (1924); 127-129. 192A.
FIG
Rust caused by Physopella fici (Cast.) Arth. was reported as less than usual in Georgia (Boyd) and Louisiana (Ndgerton). Unimportant in Texas. (Taubenhaus)
leafspot caused by Cercospora sp..was reported as prevalent in Georgia (Boyd) and Texas (Taubenhaus) |
290 FIG TO DATE PAIM
finthracnose caused by Glomerella cingulata (Ston.) Spauld. & Schrenk was reported é as Sia ata in South Carolina (Fenner) ‘and Georgia (Boyd).
Soft rot causing a loss of 5 per cent in Georgia was attributed to A Asper- —
gillus sp. and Rhizopus spe, according to Boyd, this amount being less than usual due to dry 4 weather. According to Taubenhaus of Texas a loss of one-half per cent was estimated for soured fruits, cause unknown.
Limb blight caused by Corticium sp. was reported from Georgia by Boyd.
Twig blight was reported from Washington by Frank as caused, by Botrytis spay Canker caused by Tubercu laria fici Edgerton was found in about 50 per cen ty
of the plantings in Georgia, causing a a loss of h per cent, through Bonn of twigs and limbs, and in some cases entire trees. (Boyd )
Canker Boies by Macrophoma fici Alm. & Cam. was reported from Texas. Giepeennsusl
Texas root rot caused by Ozonium omnivorum Shear was prevalent in the black lands of Texas, causing Slight loss. (Taubenhaus) ‘Reported as threaten- ing damage in Arizona.
Rootknot Aude by Heterodera radicicola (Greef) Muell. (Caconema radici- cola (Greef) Cobb) was reported from a nursery in Georgia. (Boyd) Prevalent in Texas causing trace of damage. (Taubenhaus) |
Premature “reppi ng (non-par. ') was very prevalent in Texas. (Taubenhaus)
Recent literature on fig diseases
i. Brown, Nelije A. BA mabe on a rot of the Smyrna fig in Californias Science n.s. 62; 288. 1925.
2. Caldis, Panos D. A rot of the Smyrna fig in California. Science n.’.
62: 161-162. 192m.
5. Fairbanks; R. Bs Thelfile industry in Texas. Amer. Fruit Grower AS
(Aye Cy. 20s. Ieee
4. Maffei, L. Sul parassitismo di Phomopsis cinerescens (Sacc.) Trav. sopra i rami del Fici. (Cn the parasitism of Phomopsis cineres-— cens (Sacc.) Trav. on the branches of the Fig.) Riv. Patol. Veg.
15: 37-A7- 1925.
5+ Phillips, E. H., E. H. Smith, and R. E. Smith. Fig smt. Cakhifornia
Agr. Exp. Sta. Bul. 487; 1438. 1925.
DATE PAIM
Rust caused by Graphiola phoenicis (Moug.) Poit. Unimportant in Texas Taubenhaus); Porto Rico (Cook). Leafspot caused by Exosporium palmivorum Sacc., Texas (unimportant).
Pestalozzia blight caused Dy Pestalozzia pe , Texas (unimportant) .
Recent liter ature
ee EMO ss BE. Sur Le maladie du "Bayoud" des palmiers de Figuig. Compt. Rend. Soc. Biol. Paris 92: 137- 130." ialn. Les
291 PINEAPPLE TO AVOCADO
Fruit rot caused by Thiclavionpsis paradoxa (de Seyn.) Hochn. was reported from Porto Rico as sometimes severe on fruit; unimportant during 1925. (Cook) This disease was reported by Roldan as new to the Philippine Islands.
Chlorosis, due to too much lime,-was reported from Porto Rico. Good re- | sults were obtained from spraying with iron sulfate. (Cook)
Rootrot (cause not given) was reported as troublesome in Florida.
———
Recent literature
1. lyman, L. T. The rootrot problem from the field standpoint. Ann. Short Course Pineapple Prod. Hawaii Univ. Ext. Serv. Dept. A: 99- IO. 192).
2. Roldan, E. F. The soft rot of pineapple in the Philippines and other Gountries. Philipp. Agr. 15: 597-405. Feb. 1925.
4- Sideris, C. P. Physiological and pathological studies on pineapples.
Ann. Short Course Pineapple Prod. Hawaii Univ. Ext. Serv. Dept. A:
87-99. 1925.
OLIVE
Knot or tubercle disease caused by Bacterium savastanoi EFS. was reported from California as being more serious than usual, killing many limbs or twigs; occurs only in Sacramento and lower San Joaquin Valleys; favored by copious Spring and winter rains; Manzanillo variety mainly attacked. (Horne)
Dry rot (soft nose), probably physiological, was reported to be more ser- ious than usual in California. Losses as high as 50 per cent.occurred in some orchards; fruit. soft at end, shrivels, and spoils; mostly confined to Sevillano variety. (Horne)
Recent literature
1. lLaubert, R. Die Zweigkrankheit der Oliven. (The branch disease of olives.) Gartenwelt 29: 502. 1925.
AVOC ADO
scab caused by Sphaceloma sp. was reported as widespread in Florida caus- ing serious leaf spotting.
Anthracnose caused by Colletotrichum gloeosporioides Penz. was reported as destructive on young fruit and on succulent new growth in Florida. Common but unimportant in Porto Rico. (Cook & Tucker)
AVOCADO TO PAPAYA
leafspot caused by Pestalozzia guepini. Desm. was reported as local in Florida. In Porto Rico it kills young scedlings and branches on larger trees. (Cook) It is unimportant in Texas.
Leafspot caused by Phyllosticta sp. was repor ted to be of little impor- tance in Florida. . far spot caused by Phyllachora gratissima was = epee as being common in high". places in Porto Rico. (Cook & Tucker) .
Southern blight caused by Sclorotium rolfsii Sacc. was ee as occurr— ing in one instance on nursery plants in Florida.
Footrot (cause not indicated) caused some loss in eae egal 5 and newly set trees in Florida; not serious.
Algal leafspot t caused by Cephaleuros virescens Kunze % was reported as not Serious in Florida. Very common in Porto Rico.
Recent literature
i. Anon. Avocado black cae can be controlled by Bordeaux mixture. Florida Grow. 31 (1): 34. Jan. 3, 1925.
2. Horne, Wm. T. Preliminary ae: on avocado fruit denis (Abstract)
Phytopath. 16: 80. Jan. 1926.
oo me ce in ek ei
MANGO |
Anthracnose caused by Colletotrichum gloeosporioides Penz- was reported as being,Widespread and destructive in Florida, ee the fruit and twi LES, and caus¢ daming-off of seedlings. Common in Porto Ric |
Leafspot caused by Pestalozzia guepini Desm. Sap oe from Porto Ric 0. ; : .
BEE caused by Septoria sp. was reported as unimportant in Florida. Sooty mold caused by Meliola mangiferae Earle was reported to be common in Porto Rico. - .
Withertip caused by Diplodia sp. was reported as not severe in Porto Rico.
Trunk galls (cause not indicated) were reported from Porto Rico»
eAPAYA
leafspot caused by Pucciniopsis caricae Earle was reported to be wide- spread but unimportant in Florida; also reported from Porto Rico.
Recent literature i. Mowry, Harold. Papaya culture. Florida Grower 42 (3): 36. 1925 . e. Uphof, J. C. TH. Das Verhalten von Pucciniopsis caricae Earle auf der Papaya (Carica papaya) in Florida. (Pucciniopsis caricae '
Earle, on Carica papaya in Florida.) Zeitschr. Pflanzenkrankh. 35: 118-122. 1925.
| 293 GUAVA TO PERSIMMON
- GUAVA
Anthracnose caused by Colletotrichum gloeosporioides Penz. was reported from Florida; in one oe ae Ok pplaa young fruit and leaves. Abundant in Porto Rico.
Leafspot and fruitrot caused by Gloeosporium psidii Del. was reported from several localities in Florida.
. Leafspot caused by Pestalozzia sp. was found in a few localities in Florida; unimportant. |
Root and trunk rot caused by Clitocybe monadelpha (Ne eee Sacc. (C. tabe-
scens (Scop.) Bres.) was reported from a number of localities in Florida.
te
BANANA
Anthracnose caused by Gloeosporium musarum Cke. & Mass. was reported as common on all varieties in Porto Rico. (Cook & Tucker)
Wilt caused by Fusarium cubense EFS. was reported to te destructive on certain varieties throughout Porto Rico. (Cook & Tucker)
Recent literature -
1. Ashby, S. F. Researches on Panama disease. Proc. West. Indian Agr.
Conf. 9 (1924): 51-53. 1925.
2. Benson, A. H. Leafspot on bananas. Queansl. Agr. Jour. 24: 392-494. (Oct. 1925.
54- Campbell, J. G. C. Banana diseases in Vitilevu. Agric. Circ. Dept. Agr. Fiji 5: 67-75. Jan.-June 1925.
4. Hansford, C. G. Some remarks on questions raised by the Panama dis- ease of bananas. Proc. West Indian Agr. Conf. 9 (1924); Al-5O.
1925.
Ae and J. B. Sutherland. Panama disease of bananas. Jour. Jamaica Agr. Soc. 29: 247-240. 1925.
6. Tryon, H. Banana - internal fruit discoloration. Queensland Agr. Jour. 24: 122-1245. 1925.
PERS IMMON
Leafspot caused by Cercospora sp. was reported to be general in the coastal plain region of Georgia, causing are ae Found generally in Florida but causing little damage.
leafspot caused by A guepini Desm. was reported to be very com- mon in Florida, causing defoliation in late fall.
294 PERSIMMON TO POMMGRANATE PECAN - Seab
leafspet caused by Ramularia sp. was reported from western Florida.
Black-mold caised by Macrosporium sp. was reported from western Florida, causing some defoliation. -
leaf speck caused by Leptothyr ium’ pomk - (Mont. & Fre) ‘Sacc. was more or less common on the fruits in Florida.
Anthracnose caused. by. Gloevosporium di Loar Ell. & Ev. was | general! y found in'Florida, causing some withertip.
iypochnose caused by Corticium stevens ii Burt was reported from one lo- ~cality in Florida. Une st : |
BREADFRUIT.
Rust caused by Uredo artocarvi Berk. & Br. was reported from Porto Rico. (Tucker) aera
“Algal. learspot Causee by —— virescens Kunze was reported from Porto Rico. (Tucker) oe
POMEGRANATE
‘leafspot caused by Cercospora Se Heald & hairs was sean from Florida as unimportant. Anthracnose caused by Colletotr ichum sp+ was reported on fenit and twigs
DISEASES OF NUTS
S ee PEC AN
SCAB CAUSED BY FUSICLADIUM EFFUSUM WINT.
Pecan scab is probably the most important disease of this crop.
‘
South Carolina: less than usual. Occurred: throughout the Sandhill region
northward to the edge of Piedmont area. (Fcmer)
Georgia: Pecan scab was very important in spite of general shortage of rainfall. Estimated-loss 5 per cent. Most prevalent in the southernmost countics, especially in heavy plantings of Schleys. Rainfall during May, June, and July being lighter and iess fre- guent than usual acecunted for less injury than usual. Delmas were a total Joss in most sections. Alleys and Schleys were less susceptible and scabbing about same. Much. less on Van Deman than cm Mobile and FProtcher ‘showing considersble nut infection. ( Boyd ;
‘e 29 PECAN — Scab; Powdery miidew; Rosette
Florida: Common wherever the host was growing in the state. The dis- ease was generally worse than last year. Of considerable ecoromic
importance. (Weber) Mississippi: Light infection on account of drouth. (Beal)
According to Demaree (1) all fungicides tried were found inferior to Bordeaux mixture in controlling scab. Bopdeaux, however, causes severe foliage injury urder certain conditions. Data from four orchards indicate that the cost of spraying pecans ranges from 40 to 95 cents per tree. Dusts were found to be of little value. Topworking of susceptible varieties, orchard sanitation, in- cluding plowing, and spraying with Bordeaux are recommended.
Working under Mississippi conditions Neal (2) reports the results of Bordeaux-oil emulsion for pecan scab control.
- “After the success we have obtained with it in pecan spraying under Mississippi conditions, especially for combating scab during wet seasons, we believe it far superior to the plain Bordeaux mixture, Bordeaux fish oil soap, or other fungicides which we have used."
Recent literature
1. Anon. Spray pecans this summer and control scab disease. Citrus Industr. 6 (6): 14. June 1925.
2. Demaree, J. B. Progress report on pecan scab spraying experiments. Proc. 24d Ann. Conv. Nat. Pecan Growers Assoc. 192A: 53-61. Be iege
53- Demaree, J. B. Apparent limitations to pecan scab control. Amer. Nut Jour. 12: Al-A42. Mar. 1925.
4. Neal, D- C. Bordeaux-oil emision for pecan scab control. Proc. 24d Ann. Conv. Nat. Pecan Growers Assoc. 192A: 61-63. 1925.
POWDERY MILDEW CAUSED BY MICROSPHAERA ALNI (WALLR.) WINT.
~~ \
This disease was reported from Georgia, Florida, and Texas. According to Boyd of Georgia, the varieties Mobile and Success in one orchard were heavily infected. In Florida, according to Weber, it was common on nursery stock where it caused considerable damge but otherwise was not Serious.
ROSETTE (UNKNOWN) Rosette Mi sdeeed from South Carolina, Georgia, Florida, Texas, and Kansas. A 10 per cent loss was reported oe Geo gia. Georgia: Seen on all of the varieties common here. Trees: aifected.with
this disease usually set very lightly or not at all. Many Badly affected trees lost their eatiesines entirely dur ing Mebaether and
6 e ECAN — Rosette; Other Diseases WALNUT — Bacterial blight-
October. Most serious disease of the state. Recommend improve— ~— ment of soil by cultivation and fertilization, especially the addition of organic matter. (Boyd)
Recent litcrature
i. Skinner, J. J. and J. Be Denaree. . Relation ot soil conditions and orchard mnagement to the rosette of pecan trees. U. S. Dept. Agr. Bul. 1378: 1216. Feb. 1926.
OTHER DISEASES AND INJURIES
Bacterium tumefaciens EFS. & Towm., crowngall, Florida (on a few seed- lings, not common). |
Botryosphacria berengeriana De Not te, Gieback, South Carolina (serious locally), and Florida (common and occasionally serious).
Cercospora fusaa (Heald & Wolf) semend. Rand, brown leafspot, Georgia, Florida, and Texas. In Georgia, brown spot was reported by Boyd to be "Of minor importance this year, except on trees affected with rosette."
Corticium stevensii, Florida (not common}
Glome rella cingulata (Ston.) Spauld. & Schrenk, anthracnose, Georgia (very little importance), Florida.
Microstroms juglandi (Bereng.) Sacc., leafspot, Florida.
Mycosphaerella convexula bait ate Mus Rand, leaf blotch, Florida. Pestalozzia uvicola, leafspot, Florida (Pea but not ea Phyllosticte caryae Pk., leafspot, Geo rgia (slight importance).
'. Blackpit (non-par.). Reported from Georgia where it was thought to cause 2 per Cent loss. According to Boyd, Frotcher and Schley were injured most heav- ily, ae of 5 to 15 per cent being noted. One planting of Delmas were begin- | ning to rosette to the extent of 35 per cent loss while Stewart and Schley in the same ie were not materially affected.
Die-back (undet.), Kansas (slight).
, Mouse ear bono Florida (not common. On bearing trees and nursery stock). peo
Texas root rot, Texas, Arizona. (Ozonium omnivorum Shear]
Recent literature
(il. Mahan, F. Aw. Spray injury to pecan trees. Nat. Pecan Exchange News | 2: 6-7. May 1925.
e. Wenzel, O. J. Woodrot in pecan trees. Nat. Pecan Echange News 2; 9-12. July 1925. ,
ral
ENGLISH WAINUT BACTERIAL BLIGHT CAUSED BY BACTERIUM JUGLANDIS (N. B. PIERCE) EFS.
This ,disease was reported to be very important in Oregon where it caused a loss estimated Jat 44 per cent and in California where the loss Was estimated
ay ENGLISH WAINUT TO AIMOND ;
at 4 per cent. According to Barss of Oregon, much more bacterial blight oc- curred this year than in 1924. Some of the larger growers reported it worse on seedling trees than on grafted trees while usually the reverse is true. Milbrath, of California, reported the disease worse this year than last year in all parts of the state.
JAPANESE WALNUT
Rosette (undet.) South Carolina. "Have had one report about September 1 of the rosette disease on Japanese walnut.. It resembles pecan rosette a good deal. A detailed description cannot be. given as the disease was not seen in the field. This is the first time-I have seen the disease on this host." (Ludwig)
Bacterial blight caused by Bacillus coryli was said by Barss to be much less prevalent than in 1924 in Oregon, but it-is always an important disease in that state especially on young trees the years old or on the small wood of Older trees.
AIMOND
Scab caused by Cladosporium cna ig Thuem., Oregon (no importance).
Brownrot caused by Sclerotinia cinerea (Bon.) Schroet., Californias |. (worse this year than last, destructive on Drake variety; blossom and twig in- fection in the San Joaquin Valley.)
Rust caused by Tranzschelia punctata (Pers. ) Arth., California, (worse than last y year causing promture leaf dropping.) :
Recent literature
1. Smith, R. E. and BE. H. Smith. Further studies on Je Leegons in- fection of deciduous fruit trees in California. Phytopath. £5 %
309-404. 1925.
oo uylor, BR. H. and G. 1, Phillips The almond in California. Cali+ fornia Agr. Exp. Sta. Circ. 284: 1-57. Apr. i925.
all
* 298
COCONUT - Budrot; Miscellaneous Diseases; Literature.
COCONUT
_ BUDROT CAUSED BY PHYTOPHTHORA FABERI MAUB.
This disease was reported from Porto Rico and Florida. In Porto Rico it was severe along the west coast. According to A. S. Rhoads, of Florida, | "Phytophthora faberi has not been found in the saith central and southwestern portions of the state, but is generally distributed along the southeast coast where 95 per cent of the coconuts are found. In a nursery near Miami 12 per cent of the plants have been destroyed by budrot. From 450 collections of bud- ‘rotted plants, 68 have yielded Phytophthora faberi. In making isolations from
budrotted plants such organisms as bacteria, yeasts, Nematodes, etc. are found associated with the condition, but their true role has not been determined.
MISCELLANEOUS DISEASES AND INJURIES
Colletotrichum sp., anthracnose, Florida and Porto Rico. "This organism — occasionally causes a premature falling of the fruit. Not important in Porto Raeo = (Cookd: In Florida it is coexistent with the host, causes severe spott- ing of the leaves and petioles and is of. some impo rtanée to young plants.
Exosporium sp-, leafspot, Florida (few cases, of minor importance).
Pestalozzia palmarum Cke., leafspot, reported from Florida (general, some damage on nursery plants) and Porto Rico.
Phyllosticta spa, leafspot, Florida (quite common on leaves but of little: or no importance). |
Thielaviopsis paradoxa (De Seyn.) Hoehn., ee ae disease, Porto Rico and the Philippine Islands. According to Roldan (11) this organism caus- ing softrot of pineapple, pineapple disease of sugar cane, and coconut stem- bleeding disease recently broke out in the Philippines. It is-present also. in @ Hawaii, Java, West Indies, India, Ceylon, and southern United States. . . ‘In Florida a disease called "bitten leaf" and caused by this same fungus | ‘was found quite generally on both young and old plants. In this case the chief 7
damage was the curling of the leaflets and occasional destruction of ee buds : Has been found to attack also the roots of y ota plants.
Recent literature
1. Ashby, S. F. -Budrots of the coconut palm in the West Indies. Rep. Proc. Imp. Bot. Conf. London 1924: 153-158. 1925.
A, Red ring disease of the coconut. Proc. West. Indian~*
Agr. Conf. 9: 164-172, 1925.
Bote Budrot of coconut eae in Pore Rico. Tropical haricalture er Ag Cee ts 1025.
4. Butler, E. J. Budrot of coconut and other palms. Rep. Proc. Imp. Bot. Conf. London 1924: 145-154- 1925.
-
16.
299 COCONUT - Miscellaneous Literature ~
Dowson, W. J. Some observations on the budrot disease of coconut palms on the east coast of Africa. Rep. Proc. Imp. Bot. Conf. London 192A: 159-lo1. 1925.
Gaddg, C. H. Inoculation experiments with Phytophthora faberi Maubl. Yearbook Dept. Agr. Ceylon 1925: 15-17. 1925. —
Nowell, W. Coconut budrot in Trinidad. Reo. Proc. Imp. Bot. Conf. London 1924: 161-162. 1925. |
Coconut budrot in Trinidad. Trop. Agr. 64: 277. May 192) Newell, Wilmon. Report of plant commissioner for the biennium end- ing June 30, 1924. Florida State Plant Bd. Quart. Bul. 9: 59-117. LS ay
Petch, T. A thread blight on coconuts. Yearbook Dept. Agr. Ceylon
1925: 27-20. 1925.
Roldan, EH. F. The soft rot of pineapple in the Philippines and Other countries. Philipp. Agr. 14: 397-405. Feb. 1925.
Sharples, A. Observations on budrot of Palms. Rept. Imper. Bot. Cont. London 1924: 147-153. 1925.
Shepherd, H. F. S. Une maladie suspecte des racines du cocotier. Rev. Agr. Ile Maurice 1925: 402-A8A. May-June 1925.
Tucker, C. M. Coconut budrot experiments in Porto Rico. Science 61:
186-187. 1925.
Controlling coconut budrot. West India Comm. Circ.
AG= Lt. Jane 192).
Mesures de controle de la pourriture du coeur du
cocotier. Rev. Agr. Ile Maurice 1925: 421-422. Mar.-April 1925.
* Ga ‘i i Pa A. E A AEE: Wag ; Pinirmeo to). he eee H ‘ 7 te cs x
a ae Ph a * ES ears Br eae SOON: CERES: | Lee
‘ “ $2 vag 1 } SS ae ’ a oe ey ey Bit to) 7. Ofte . ay ‘Tes pS a nee Pai biol Ub Peete em, : : Tee eee AB aia Sipe kg ee EB a A aR: ‘ f3 7 — ty f é ak iia | ik Ox Sipe ies > 4 pa 2 “ i { 5 re nee ; Ni Py Rik: ge te eo ee . SSM leas WE his oR: Or. Aa Be Ons 3 ; , ‘eis ; f : : 4 é » - , } i " 5 d } sy ' p , i m H a: Bart! LO Ls oe ? ce 5 a, “5 ‘ple v1 . 4 if oat date * tie ay / Ne Nie cpt S ta ; ra ne 2? = suey po +5 [: Poe i ae fe ™ >! ‘ . Eee, <% «cals : ’ Se St of, ae MDS oe heb SESS he SERRE ae ma sey) wT ae ; = : 4 J ; nt Ape. ae re ae t) aS 2 J HACER ei a b i ” s E ; ried ? 4 Le 2 Msi bee Ses) § ai tot ere (eee ne OR a ; ha phe: > by eg 3 ' a sf idea ee ay fray G Reais Saye Wb ie A hg 4% ¢ ets a5 ? - “ Z ee eat | ; ~ae* aah) 3 MG é ‘ i ; : = i ; wee i = ) - ‘ ‘ . : # ee ry 7 ¥ +e oy Ji a a ? ne 5 Ve 5 - : 5 . : + & Fs oh 1 ide ve wy) via aor Ao A oe od 5 ne +P % ae » . Y Pa ad eka) x 5 ee ait} Pe ae ¢ A id 4 yet ‘ aa E = A ee 2a, Pe Py by #. ve; 3 eS <a 1 a cat wD ; a i ¥ 4 mre te OT ae . ela ¥ as Erie ne ae * oj . ay re rake ire we a y ee: \ : si a Cy = : oe ee a a ater tne s . +2 3 A tae Wie CE ROD 2 edie bees Bea hod sine Pao . Fa oF Y . Phi » . 9 ia < P 07 e) ates ri aeX p P 4 . ER he SERS f08 Pires iin : wi 5. eae i z Day 4 : © J pes * mm * Bay a slats oi ren ae p ‘ ie i ‘ A ne ee Ma ORF, : , : ee: 3 +P etary i) dee, Fx = ry fe ae eo ee a $i ‘as Pee 2 ; pare 4S tito - tao + % +f z ree eae 4 Rik. Bs ie : et ores ote MBE} Boa 33 ca} ty Stee H - , Mists igs Sie : ook ra p a ‘ine '
ze