Historic, archived document

Do not assume content reflects current
scientific knowledge, policies, or practices

U. S. DEPARTMENT OF AGRICULTURE.

BUREAU OF PLANT INDUSTRY— BULLETIN NO. 200.

B. T. GALLOWAY, Chief of Bureau.

BREEDING NEW TYPES OF
EGYPTIAN COTTON.

BY

THOMAS H. KEARNEY,

Physiologist in Charge of Alkali and Drought Resistant
Plant Breeding Investigations.

Issued December 23, 1910.

WASHINGTON:

government printing office

1910.

BUREAU OF PLANT INDUSTRY.

Chief of Bureau, Beverly T. Galloway.
Assistant Chief of Bureau, 6. Harold Powell.
Editor, J. E. Rockwell.
Chief Clerk, James E. Jones.

Alkali and Drought Resistant Plant Breeding Investigations.

scientific staff.

Thomas H. Kearney, Physiologist in Charge.
H. L. Shantz, Physiologist.
A. C. Dillman, Assistant Physiologist.
200
9.

LETTER OF TRANSMITTAL.

U. S. Department of Agriculture,

Bureau or Plant Industry,

Office of the Chief,
Washington, D. C, August 18, 1910.
Sir : I have the honor to transmit herewith and to recommend for
publication as Bulletin No. 200 of the series of this Bureau the
accompanying manuscript, entitled "Breeding New Types of Egyp-
tian Cotton," by Mr. Thomas H. Kearney, Physiologist in Charge of
Alkali and Drought Resistant Plant Breeding Investigations.

As a result of experiments that have been carried on for the past
seven years in acclimatizing and breeding Egyptian cotton in the
southwestern United States, several distinct types have originated
from the stock of imported seed of the Mit Afifi variety with which
the work was begun. Two of these are as distinct in the characters of
the plants, bolls, and fiber as some of the newer varieties which have
originated in Egypt from the Mit Afifi. A third promising type is an
improved acclimatized strain of Mit Afifi rather than a new variety.
The principal object of the present publication is to describe the
leading characteristics of these promising varieties and strains and
the methods followed in the plant-breeding work. A brief account
is also given of the general progress of the acclimatization experi-
ments with Egyptian cotton during the year 1909.

The United States continues to import large quantities of staple
cotton. In 1909 the imports from Egypt amounted to 72.617,893
pounds, valued at $12,101,000. Spinners who have examined samples
of the acclimatized Egyptian fiber grown last year in the Southwest
pronounce it to be in every way as Avell adapted to their requirements
as imported cotton of corresponding grades.

The possibility of growing Egyptian cotton of good quality on the
irrigated lands of southern Arizona and southeastern California has
been demonstrated. Production on a large scale awaits the solution of
certain cultural and commercial problems which are now receiving
attention.

Respectfully,

G. H. Powell,
Acting Chief of Bureau.
Hon. James Wilson,

Secretary of Agriculture.

200

3

CONTENTS.

Page.

Introduction 7

New types developed 9

Methods of selection 10

The Yuma variety 13

History of the variety previous to 1909 13

Breeding experiments in 1909 15

Field test in 1909 16

Characters of the plants and fiber 17

Performance of nearly related types 18

Probable mutative origin of the Yuma variety 19

The Sonierton variety 20

History of the variety previous to 1909 20

Experiments in 1909 21

Characters of the plants and fiber 22

Performance of a nearly related type - 23

Probable mutative origin of the Sonierton variety 23

Strains Nos. 360, 361, and 362 24

Origin of the group - 24

Strain No. 360 24

Strain No. 361 25

History 25

Field test in 1909 26

Strain No. 362 27

General characteristics of strains Xos. 360, 361, and 362 28

Imported seed of Egyptian varieties tested in 1909 28

Miscellaneous experiments in 1909 29

Progeny of first-generation hybrids 29

Production of first-generation hybrids 29

Seed selection _ 30

Different dates of planting 30

Seed from different pickings 30

Irrigation 30

Present commercial status of Egyptian cotton in the United States 31

Conclusion 32

Summary 33

Description of plates 36

Index 37

200

5

ILLUSTRATIONS

Page.
Plate I. Fig. 1. — A fertile plant of acclimatized Egyptian cotton. Fig. 2. —

A plant of the Yuma variety of acclimatized Egyptian cotton 36

II. Typical bolls and bracts of Mit Ann Egyptian cotton grown from

imported seed 36

III. Typical bolls and bracts of the Yuma variety of acclimatized Egyp-

tian cotton 36

IV. Typical bolls and bracts of the Somerton variety of acclimatized

Egyptian cotton 36

200

6

B. P. I.— 611.

BREEDING NEW TYPES OF EGYPTIAN
COTTON."

INTRODUCTION.

The work of the Bureau of Plant Industry with Egyptian cotton
in the Southwestern States and Territories involves three closely
related but somewhat distinct lines of investigation, as follows:

(1) Plant-breeding investigations, the object of which is to secure
improved, high-yielding varieties and strains by the selection of
superior individuals producing fiber which represents the best com-
mercial types of Egyptian cotton. The present publication deals
mainly with this phase of the work.

(2) Acclimatization investigations, the object of which is to study
the diversity exhibited b}T imported and by more or less acclimatized
stocks when planted under different environmental conditions, so as
to ascertain what environments and what cultural conditions are
most favorable to uniformity, fruitfulness, and the production of
good lint in each stock.6

(3) The study of irrigation and other cultural methods for grow-
ing the crop and of industrial methods for preparing and market-
ing the product. These studies are directed by the officers of the
Bureau of Plant Industry who are in charge of the cooperative

0 The general results of the experiments with Egyptian cotton in the south-
western United States up to the end of the year 1908 were described in Bulle-
tin 128 of the Bureau of Plant Industry, entitled " Egyptian Cotton in the
Southwestern United States," and in Circular 29 of the same Bureau, entitled
" Experiments with Egyptian Cotton in 1908," both publications being by
Thomas H. Kearney and William A. Peterson.

& Some of the results of the investigations in this field by Mr. O. F. Cook
and his assistants are described in the following publications of the Bureau
of Plant Industry : Bulletin 147, entitled " Suppressed and Intensified Char-
acters in Cotton Hybrids," by O. F. Cook, 1909; Bulletin 156, "A Study of
Diversity in Egyptian Cotton," by O. F. Cook, Argyle McLachlan, and Rowland
M. Meade, 1909 ; Circular 42, " Origin of the Hindi Cotton," by O. F. Cook, 1909 ;
Circular 53, "Mutative Reversions in Cotton," by O. F. Cook, 1910.

200

7

8 BREEDING NEW TYPES OF EGYPTIAN COTTON.

work with the Reclamation Service and with the Office of Indian
Affairs, respectively. Mr. W. A. Peterson, superintendent of the
cooperative experiment farm of the reclamation project at Yuma,
Ariz., and Mr. E. W. Hudson, superintendent of the cooperative ex-
periment farm on the Pima Indian Reservation at Sacaton, Ariz.,
are in immediate charge of the cultural experiments. Most of the
experimental work with Egyptian cotton in the Southwest has thus
far been carried on at these two stations.

In 1909 the plant-breeding plats were located in the Yuma Valley a
and at Sacaton, Ariz. In the Yuma Valley two fields were planted
with bulk seed of the two most promising of the new types described
later, four fields were each planted with imported seed of one of
the Eg}7ptian \7arieties, and various smaller experimental plantings
were made. At Sacaton, in addition to the plant-breeding plat and the
plats grown from imported seed of Egyptian varieties, a field of 10
acres was grown from mixed seed of the " bulk selections " made at
Sacaton in 1908. In the Imperial Valley, California, small field
plantings of four different t}7pes of the acclimatized stock were made,
each in a different locality. Another of the acclimatized types was
tested at Glendale, near Los Angeles, Cal., alongside a planting of
newly imported seed of the Mit Afifi variety.

The results of the season's work were on the whole very encour-
aging. For the first time in the course of these experiments, fields of
several acres each were planted to high-bred varieties and strains,
each derived from a single individual plant selected in the breeding
nursery only two years previously. A gratifying degree of uni-
formity in the plants and fiber was exhibited. The best three of
these new types are described in detail in the present publication.
Two of them, the " Yuma " and the " Somerton " varieties, are so
distinct from the Mit Afifi variety, with which the breeding work
was begun, as to warrant the assumption that they constitute muta-
tions. The third (strain No. 361) is a typical Mit Afifi, but superior
in yield, earliness, and quality of the fiber to plants growm from
imported seed of that variety. This strain is apparently a product
of acclimatization and selection without the aid of mutation.

The great amount of diversity that manifested itself in the experi-
mental fields in 1908 was largely eliminated, partly as a result of
planting these selected stocks and partly through the application of
methods of " roguing " at an early stage in the development of the

° The experimental plantings in the Yuma Valley in 1909 were located near
the village of Somerton, about 14 miles south of the town of Yuma. In 1910
most of the experimental work near Yuma is located on the new cooperative
experiment farm situated on the California side of the Colorado River, about 7
miles above the town of Yuma.
200

NEW TYPES DEVELOPED. 9

plants which Mr. Cook has worked out as a result of his studies of
diversity. Samples of the fiber produced at Somerton and Sacaton
in 1909 were submitted to a number of buyers and spinners, who have
given uniformly favorable reports on its quality. Comparisons with
cotton of the corresponding grades imported from Egypt have in-
variably been favorable to the Arizona product.

NEW TYPES DEVELOPED.

The varieties and strains ° of Egyptian cotton described in this
paper were derived from a stock of seed of the Mit Afifi variety
imported from Egypt by the Office of Seed and Plant Introduction
and Distribution and tested at several localities in the Southwest in
1902. 6 They are all descended from individual-plant selections made
in the field at Carlsbad, N. Mex., that was planted with this seed.
In 1906 the surviving progenies of these selections were transferred
to Yuma, Ariz., and since then the breeding work has been continued
in that locality. In 1909 a plant-breeding nursery was started at
Sacaton, Ariz., with seed of a number of individual selections from
the progeny rows at Yuma of the previous year, in addition to seed
of a number of individual selections made in 1908 in the 10-acre field
at Sacaton.0

a In this bulletin the term " variety " is applied to such of the new forms as
can easily be distinguished from the original stock by their botanical charac-
ters. The two new varieties described are believed to have originated as muta-
tions. Where the differences are simply of degree — greater fruitfulness, earlier
ripening, longer and stronger fiber, etc. — and no evidence of mutation is shown,
the term " strain " is employed.

6 For an account of the earlier experiments, see Bulletin 128, Bureau of Plant
Industry, United States Department of Agriculture, 1908. pp. 34^5.

c The field planting of 1908 at Sacaton was made with mixed seed from the
1907 breeding rows at Yuma. As would be expected, considerable diversity was
noted among the plants in this field. A large number of individuals which
were superior to the average in fertility and in fiber qualities and which
appeared to be purely Egyptian in all their characters were marked and picked
separately. The mixed seed from these plants was used for planting the " gen-
eral field" at Sacaton in 1909, in order to ascertain the general fertility and
state of acclimatization of the stock after the removal of all hybrids and other
conspicuously inferior individuals and to afford a further opportunity for the
selection of desirable types of plants that might appear under the Sacaton con-
ditions. The result was a marked improvement in average fruitfulness and in
the quality of the fiber as compared with the 1908 field. The same method of
" bulk selection " was repeated in 1909. It will be interesting to compare the
performance of this second generation of bulk selections with that of carefully
selected varieties and strains derived from single individuals, which will also
be tested on a field scale at Sacaton in 1910.
59050°— Bui. 200—10 2

10 BREEDING NEW TYPES OF EGYPTIAN COTTON.

METHODS OF SELECTION.

The breeding methods employed have been very simple. At the
outset all the plants in the test field were examined, and those indi-
viduals which were most fruitful, ripened earliest, and had the largest
bolls and the best fiber were given numbered tags and were picked
separately. The seed cotton from these plants was then carefully
compared in the laboratory and the final selection of the most prom-
ising individuals was made.

The following year the seed from each of these selections was
planted in a progeny row, and each row was marked with the number
of the corresponding selection. When the bolls began to open in the
fall the rows were carefully worked over, and the best individuals
were selected. This process has been continued year after year.

As the work developed, the methods were improved. Latterly
more importance has been attached to the " projected efficiency " of
the individual selections as shown by the greater or lesser degree of
uniformity in the good qualities of their progeny. It is now the
practice to begin the work of selection each year by a general survey
and comparison of the progeny rows as units. As a result, many of
the rows can be rejected at once, either because the plants show too
much diversity or because their average fruitfulness, length of lint,
and other qualities are inferior. Further consideration is given to
only those rows which show a high degree of uniformity and in which
at least a majority of the individuals are desirable in all essential
qualities.0 The best individuals in the superior rows are then se-
lected by careful comparison in the field, the branching habit and
productiveness of the plants and the size of the bolls being noted
and the lint from a number of bolls on different parts of the plant be-
ing combed out and examined in respect to length, strength, and
general quality.

Evidence has accumulated to the effect that the type of branching
of the plant is one of the most important characters to be considered
in making selections. Plants which bear a large proportion of the
bolls on the fertile branches of the main stem, with a corresponding
reduction in the size of the " limbs," & are to be preferred because

aAn exception should be made to this rule in the case of strikingly superior
individuals which are so distinct as to warrant the belief that they are muta-
tions. Such individuals should be retained even if the rows in which they
occur are otherwise inferior, iD view of the generally admitted tendency of
mutations to be prepotent.

6 The distinction between the fertile branches and the " limbs," or large vege-
tative branches (which in Egyptian cotton are produced only at a few of the
lowest nodes of the main stem), is well expressed by Mr. O. F. Cook in Bulletin
156 of the Bureau of Plant Industry, p. 29: "The branches of the cotton plant
are of two definitely different forms. Fertile branches are horizontal or drooping.
200

NEW TYPES DEVELOPED. H

they are much easier to pick and because the ripe bolls are held up
better and escape contact with dust and mud. The ability to develop
fruiting branches at low nodes of the axis — in other words, to set a
" bottom crop " — is a desirable character, being an important factor
in great fruitfulness. The size of the bolls must be considered, not
only because large bolls make picking easier, but because this char-
acter is intimately associated with length of fiber.0 It was discovered
last }^ear that an examination of the breeding rows several weeks be-
fore the bolls begin to ripen is exceedingly helpful, since it is much
easier at that period to compare the different rows in respect to type
of plant and amount of diversity. The percentage of contamination
that has resulted from preA7ious crossing with other types is especially
easy to determine at this early stage.

The seed cotton from the preliminary selections made in the field
is picked separately, and the fiber is carefully examined and com-
pared on the seed in the laboratory. The seed cotton from each
plant is then ginned, and the color of the resulting fiber is deter-
mined by matching with imported samples of the different Egyptian
varieties.6 The average amount of fuzz on the seeds is also recorded
after ginning. By a careful comparison of the field notes on produc-
tiveness, earliness, vegetative characters of the plants, and size of the
bolls with the results of the examination of the fiber in the laboratory,
the final choice is made of the selections to be retained for planting
in progeny rows the following year, and the rest are discarded. The
more promising types are tested on a field scale by planting in differ-

Eacli joint bears a fruit bud. and tbe internodes are twisted to bring the
buds to tbe upper side. Sterile branches, or ' limbs,' are upright or ascending,
with long straight joints and no fruit buds. The sterile limbs are to be thought
of as subdivisions of the main stalk and have the same function. Like the
main stalk they can produce other branches which are fertile, but are them-
selves unable to set any flowers or fruits."

a Mr. O. F. Cook has called attention in Bulletin 159 of the Bureau of Plant
Industry, p. 45, to the existence of this correlation between the length of the
boll and the length of the fiber. The writer has observed that in Egyptian
cotton, although extremely long, narrow bolls sometimes contain inferior fiber,
very short, rounded bolls are never correlated with long lint.

1 Mit Afifi has the most deeply colored fiber. A comparison of the imported
sample of this variety, which has been used as a standard, with the band-painted
specimens of color tints given in Ridgway's " Nomenclature of Colors " (Boston,
1886) sbows tbe color of tbis sample to be very nearly intermediate between
" cream-buff " and " pinkish-buff " ; Nubari is somewhat lighter colored, corre-
sponding very nearly with tbe " cream color " of Ridgway ; Jannovitch fiber is
much lighter colored than Nubari and may be described as of a very pale tint
of cream color ; Abbasi fiber is white, tinged with cream. To conform with com-
mercial usage, however, the terms "brown" (Mit Afifi), " ligbt brown"
(Nubari), "cream colored" (Jannovitch), and "white" (Abbasi) will be used
in this paper.
200

12 BKEEDING NEW TYPES OF EGYPTIAN COTTON.

ent localities the mixed seed from the unselected plants in the progeny
rows. The degree to which the type maintains its uniformity and
desirable qualities of plant and fiber when grown in large fields,
especially if at different localities affording a considerable diversity
of climatic and soil conditions, is, of course, the final measure of its
agricultural value.

The types represented by progeny rows in the breeding nurseries at
Yuma and Sacaton in 1909 were designated by the following num-
bers: 300, 301, 310, 320, 330, 340, 350, 360, 361, 362, 363, 370, 380, 382,
383, and 390. Each of these numbers is that of an individual selection
made at Yuma in 1907 and of the corresponding progeny row grown
at Yuma in 1908. All types the numbers of which belong to the same
decade (as 300 and 301, 360 to 363, etc.) are closely related, having
been derived from the same individual plant selected at Yuma in
1906. All types numbered from 300 to 310, inclusive, came from one
individual selected in the field at Carlsbad, N. Mex., in 1902, and all
those numbered from 350 to 390, inclusive, are derived from several
individual selections made in the breeding nursery at the same place
in 1905.°

The progenies of numerous individual selections in each of the
above types were grown on the " plant-to-a-row " system in the
breeding nurseries at Yuma and at Sacaton in 1909. Strain No. 361
and the Yuma variety (No. 382) were tested on a field scale near
Yuma, seed from the unselected plants in the respective progeny
rows of 1908 having been used for these plantings. Selections from
the progeny rows of the following seven types have been planted in
the breeding nurseries of the present year (1910) at Yuma and
Sacaton: Nos. 301, 310, 360, 362, 370 (the Somerton variety), 382
(the Yuma variety), and 390.

Heretofore the various progeny rows of all the types represented
have been grown side by side in the breeding nurseries, with no at-
tempt to isolate one from another. Even under these conditions most
of the rows in 1909 showed a definite unity of type. This indicates a
strong tendency to prepotency in the characters of several of these
types, for in Arizona the Egyptian cotton generally crosses very freely
even with other species when grown near by, and a high percentage
of hybrids results.6 Hereafter, in order to prevent, if possible, any

a Owing to an accident to the stakes at the heads of most of the rows in the
breeding nursery of 1905, the detailed records of the earlier ancestry of strains
350 to 390 were lost, but they are all descended from the same stock of imported
Mit Afifi Egyptian seed that was grown at Carlsbad in 1902.

h Owing to the fact that plats of Upland varieties were grown in the neigh-
borhood of the breeding rows of Egyptian cotton at Yuma in 1907, many of
the progeny rows in 1908 contained a high percentage of hybrids. In one row
there were as many as 25 per cent of first-generation Egyptian-Upland hybrids.
200

NEW TYPES DEVELOPED. 13

contamination due to intercrossing of the different stocks, the progeny
rows of each of the most promising types will be isolated, as far as
practicable, from all cotton of different ancestry.

The three most promising types that have so far been developed in
the course of this breeding work are described in detail in the follow-
ing pages. The remaining types either appear less promising or
have not yet been sufficiently tested.

THE YUMA VARIETY.

Type No. 382, here designated the " Yuma " variety, is upon the
whole the most promising that has so far been developed in this breed-
ing work, and is the one which has been most thoroughly tested on a
field scale. In 1909 a field of 4^ acres near Yuma, Ariz., was planted
to this seed, and a high degree of uniformity was noted in the char-
acters of the plants, which were very productive and had large bolls
with lint of good quality. Seed of the Yuma variety was planted in
1910 at all localities where experiments with Egyptian types of cotton
were undertaken, in order to test its power of retaining its desirable
qualities under a variety of conditions of climate and soil.

HISTORY OF THE VARIETY PREVIOUS TO 1909.

The progenitor of the " Yuma " variety was a plant selected in the
breeding nursery at Carlsbad, N. Mex., in 1905. It was derived from
the stock of Mit Afifi Egyptian seed planted at Carlsbad in 1902,
from which all the other types described in this paper are likewise
descended. In the progeny row grown at Yuma, Ariz., in 1906 from
the Carlsbad selection an individual was selected which was char-
acterized by high productiveness, very large bolls, nearly smooth
seeds, a high percentage of lint (32 per cent), and fiber that was very
satisfactory in length, strength, and fineness. The progeny plants of
this selection in 1907 were of excellent average quality. One of the
selections, No. 382, from this progeny row was the immediate pro-
genitor of this variety. It was a very productive plant, with large,
long-pointed bolls, and its fiber was silky and lustrous, very strong,
and more than 1 J inches in length.0 The lint percentage (27) was
considerably lower than that of its progenitor in 1906.

The amount of crossing which takes place under these conditions in Arizona
seems far in excess of what has been observed by most cotton breeders in the
eastern United States. It can doubtless be attributed to the unusual abun-
dance of wild bees and other flower-visiting insects in the cotton fields during
the summer and early fall.

a Measurements of length of fiber are copied from the score cards of the year
the sample was grown. It is probable that the length was somewhat too favor-
ably estimated previous to 190S, the earlier practice having been to give the
200

14 BREEDING NEW TYPES OF EGYPTIAN COTTON.

The progeny row in 1908 from selection Xo. 382 was remarkably
uniform in the characters of the plants, bolls, and fiber.0 The plants
were characterized by great productiveness and by a habit of growth
(PI. I, fig. 2) that distinguished this row from all the other progeny
rows in the nursery. They had a tall, stout main stem, which gen-
erally greatly surpassed the limbs and bore an exceptionally large
proportion of the bolls. The bracts of the involucre were very large
and the bolls were long and pointed. The seeds were generally nearly
smooth. The average length of fiber equaled or exceeded that of any
other of the 1908 progeny rows, and the length throughout the row
was fairly uniform. The seed cotton from all the unselected plants in
this row was picked and ginned together. As measured by Mr. John
A. Walker,6 the resulting lint ranged from 1J to If inches in the first
picking. If to lT7<j inches in the second, and 1TV to H inches in the
third picking. In respect to fineness. Mr. Walker classed the lint
from the first two pickings as " fine " and that from the third picking
as " strictly fine and silky." He found the strength to be " fair "
in the first picking and " extra " in the second and third, but in all
three pickings the strength was slightly uneven. The color of the
lint from all the pickings was light brown.

Twenty individual selections were made in this row. and the seed
cotton from each was carefully compared. Although the fiber was
generally of high quality, there was much diversity among the differ-
ent plants and even on the same plant, especially as between the
first and the third pickings. In 13 of these plants the fiber had the
same color as imported samples of the Jannovitch variety (see foot-
note b. p. 11). in 1- plants the color was intermediate between Janno-
vitch and Xubari. in 1 plant the fiber was nearly as brown as Nu-
bari. and in another nearly as white as Abbasi. The maximum length
of fiber in the 20 selections ranged from ly% to 1-JJ inches, in 16
plants the length did not fall short of If inches, in 7 plants none of
the fiber was shorter than 1TV inches, and in 2 plants the minimum

fibers a decided pull in straightening thein out before measuring them. During
the last two years the fibers have been merely smoothed out, without applying
tension. It is therefore probable that the deterioration of the progeny of many of
the selections which is indicated by length of the fiber shown on the score cards
is apparent rather than real. It is believed that the method now followed gives
a better idea of the length as usually estimated commercially on samples of
ginned cotton; error, if any occurs, is in the direction of too great conservatism.

a This row contained only 4 per cent of first-generation Egyptian-Upland
hybrids, as compared with 6 to 25 per cent in eleven other rows in the breeding
nursery. The small percentage of hybrids in row 3S2 indicates a high degree
of prepotency in this type.

6 An expert grader of Egyptian cotton, employed by the Bureau of Plant In-
dustry to classify the lint from the different experimental plantings in Arizona
in 1908.
200

NEW TYPES DEVELOPED; 15

length was 1J inches. The variation in length on the same plant was
generally considerable, especially as between the first and the third
pickings. The fiber was uniformly silky and very fine, especially in
the later pickings. In nearly all plants the strength was satisfactory,
and in 7 out of the 20 it was highly so. The percentage of lint
varied considerably, having been only fairly good on 8 out of the 20
plants, while on the other 12 it was more satisfactory. In 10 out of
the 20 selections the seeds varied from nearly smooth to partly cov-
ered with fuzz, in 5 they wer© nearly smooth, and in the other 5
they varied from nearly smooth to completely fuzzy. The third pick-
ing almost always showed a higher percentage of nearly smooth seeds
than did the first.

V

BREEDING EXPERIMENTS IN 1909.

The seed from 14 of these selections was planted in 1909 in progeny
rows, 8 at Yuma and 6 at Sacaton. When inspected by Mr. Argyle
McLachlan on July 6, there was considerable diversity in 3 of the
8 rows at Yuma, although the foliage type (large, thick, dull-colored,
generally three-lobed leaves) was fairly uniform in all. In one row
no evident hybrids were found, while in the other rows 2 to 6 per
cent of the plants Avere hybrids and were roguecl out. In Septem-
ber the tendency to develop a stout main stem greatly overtopping the
limbs was found to be much less pronounced than in progeny row
No. 382 of 1908. The plants were generally productive and early
ripening, with long spreading or drooping fruiting branches well fur-
nished with bolls. The bracts were large, the bolls large and taper
pointed, and the seeds generally partly covered with fuzz.a The
color of the fiber was generally about that of imported Jannovitch,
but was frequently a deeper shade of brown. An unfavorable char-
acter was the readiness with which the ripe seed cotton dropped from
the open bolls, a peculiarity which necessitates frequent picking.
In 4 of the 8 rows at Yuma no selections were made, the fiber having
been uniformly short. In fact, none of the rows averaged nearly as
good in length of fiber as did th,e progeny row of 1908 in which their
progenitors were selected.

In the 6 rows at Sacaton the plants were very similar in habit,
foliage, shape of bolls, productiveness, early ripening, and fiber char-
acters to those at Yuma. One row contained no recognizable hybrids,
but from each of the other rows 1 to 5 hybrids or otherwise aberrant
individuals were roguecl out on August 3. Two of these rows were
later discarded, the fiber being uniformly too short to warrant making
selections.

a There is a general tendency to an increased development of fuzz on the seeds
in Egyptian cotton grown for several generations in the Southwest.
200

16 BEEEDIXG NEW TYPES OF EGYPTIAN COTTON.

Individual selections of the Yuma variety were made in 1909 in 4
of the progeny rows at Yuma aud in 4 of the rows at Sacaton. the
total number of selections being 16 at Yuma and 23 at Sacaton. In
addition to these. 32 individual selections were made in the large field
planted to this variety at Yuma, which is described in the following
paragraphs. The seed of these selected plants is being grown in
progeny rows at Yuma and Sacaton in 1910.

FIELD TEST IN 1909.

Seed from the unselected plants in progeny row Xo. 382, grown at
Yuma in 1908. was picked together and was used in 1909 for plant-
ing a field of 4J acres in the Yuma Valley. The soil was a rather
light loam, and although probably as uniform as could be found in
any area of equal size in that locality, there was sufficient difference
in soil texture in different parts of the field to cause certain spots to
dry out more rapidly after irrigation. The plants in these spots
were smaller, the leaves smaller and lighter colored, the flowers
opened earlier, and the bolls were generally smaller and opened
earlier than elsewhere in the field. The lint was also generally
shorter, coarser, and weaker on the plants growing in these spots.

From June 17 to June 22 this field was carefully inspected by Mr.
Argyle McLachlan, who rogued out about 2 per cent of the total
number of plants as being hybrids or otherwise conspicuously aber-
rant. On July 24 the field was again carefully examined by Mr.
McLachlan and the writer: the plants then appeared remarkably
uniform in branching habit, foliage, and other characters. Upon
closer examination about one-half of 1 per cent of the plants were
found to give indications of hybrid origin or were otherwise aberrant,
and these were removed. As the result of these two roguings. there-
fore, not more than 2J per cent of the entire stand of plants were
found to be appreciably different from the type of the variety. This
indicates a very satisfactory degree of uniformity and also a high
degree of prepotency, since the progeny row of 1908. which furnished
the seed for planting this field, was situated among rows of very
different types, in some of which there was a high percentage of
hybrids with Upland varieties. (See footnote I), p. 12.) Such diver-
sity as was exhibited later in the season by the plants that remained
after the second roguing seemed to be well within the limits of
individual fluctuation in a " pure " type.

The total yield from this field of 4^ acres was 7.390 pounds of seed
cotton, or 1.710 pounds per acre. On the basis of an average lint
percentage of 27.5 a this is equivalent to a yield of slightly above 475
pounds of fiber per -acre.

aA 25-pound sample of seed cotton from the first picking Yielded 29 per cent
of lint, an equal weight from the second picking 30.4 per cent, and an S5-pound
200

NEW TYPES DEVELOPED. 17

The relatively low percentage of lint given by the acclimatized
Egyptian cotton as compared with the percentages reported in Eg}^pt
and those obtained during the earlier years of the acclimatization
work in the Southwest is largely explained by an observation made
by Mr: McLachlan, who finds that the delinted seeds are considerably
larger and heavier in the acclimatized types as now developed. Mr.
McLachlan found that imported Mit Afifi seed cotton gave a lint
percentage of 33 to 35 and that the delinted seeds weighed only 10
grams per 100. The acclimatized Yuma variety, which gave only
27.5 per cent of lint, had seeds weighing 13 grams per 100. If the
seeds had weighed no more than imported Mit Afifi seeds the lint per-
centage of the Yuma variety would have been 33 (a satisfactory per-
centage for Egyptian cotton) instead of 27.5. Evidently, therefore,
no actual diminution in the quantity of lint on the individual seeds
has taken place during the process of acclimatization.

CHARACTERS OF THE PLAXTS AXD FIBER.

The distinctive features of most of the plants in this field were the
same as those of the select progeny rows of the Yuma variety as pre-
viously described. The plants (PL I. fig. 2) were large and showed a
strong tendency to develop a stout main stem surpassing the limbs in
height and to produce and retain their fruiting branches well toward
the base of the main stem and larger limbs.a The fruiting branches
were long and spreading or drooping and bore numerous bolls. The

sample front the third picking 27.2 per cent, giving an average for the three
pickings of 29 per cent. But since another sample of 50 pounds of seed cotton
made up of equal weights from each of the three pickings yielded only 26 per
cent of lint, it is deemed fair to take 27.5 per cent, the average of these two
results (29 and 26), as the closest possible approximation to the average lint
percentage for the entire product from this field, very little of the total having
been ginned at this writing.

a Mr. Argyle McLachlan early in the summer made a special study of the
plants in the 4-acre field with respect to fruiting branches. He found that the
first fruiting branch was developed at the ninth to fourteenth node from the
base of the stem as compared with the thirteenth to seventeenth node in a
planting of imported seed of the Mit Afifi variety. On thirty representative
plants from different parts of the field the average lowest node at which a
fruiting branch developed was the tenth. It has been pointed out by Mr. Cook
that ability to develop fruiting branches at low nodes of the stem, and hence
to set a " bottom crop," must considerably increase the earliness and yield of a
cotton plant.

The type of plant characteristic of the Yuma variety is described in Mr.
McLachlan's report as follows : " The plants are 6 to S feet tall with a leading
main stem, 5 or 6 vegetative branches nearly as long as the axis but loaded
with fruit and consequently spreading at an angle of 50 to 60 degrees, and above
them on the axis pendent fruiting branches — a plant of symmetrical, broad-
spreading, inverted-kite shape."
59050°— Bui. 200—10 3

18

BREEDING NEW TYPES OF EGYPTIAN COTTON.

leaves were large, comparatively dull green, and usually three lobed.
Even when five lobed the leaves were considerably longer than broad,
owing to the great length of the middle lobe. The bracts of the
involucre were exceptionally large and more or less connate at the
base, and the bolls were long and taper pointed (PI. III). The bolls
opened early and completely and there was a somewhat marked
tendency to drop the ripe seed cotton. The seeds were generally large
for an Egyptian type of cotton and bore a greater amount of fuzz
than is usually the case with seed of Mit Afifi cotton as grown in
Egypt. The fiber was of fair length (ranging from 1J to lTTe inches,
averaging probably If), of satisfactory strength and fineness, and of
a pale-brown color, intermediate between that of the Nubari and that
of the Jannovitch varieties, as represented by samples imported from
Egypt. (See footnote b, p. 11.)

The strength and fineness of the lint were tested by Mr. L. H.
Dewey, in charge of Fiber Investigations, the tests having been made
on three samples of the bulk cotton from unselected plants in the
general field. Two of the samples were from the second picking
only, while the third sample was made up of equal parts from the
first, second, and third pickings. Fiber ginned from the mixed seed
cotton of the unselected plants in one of the progeny rows of this
variety at Sacaton was also tested. The results of the tests were as
follows :

Table I. — Strength and diameter of fioer of the Yuma variety of acclimatized
Egyptian cotton grown at Yuma and at Sacaton. Ariz., in 1909.

Breaking strength.

Sample.

Average. Variation.

Diameter.

Average, i Variation.

Field at Yuma:

Second picking only <

First three pickings, equally mixed

Progenv toav at Sacaton

Grams.
6

Grams.
4 - 9. 5
4 -11
4-8.5
4. 5-11

Microns.
24

24.5
27
25.3

Microns.
18. 5-30
19 -30
22. 5-33. 5
22. 5-33. 5

PERFORMANCE OF NEARLY RELATED TYPES.

Tests made in 1909 of two other types (Nos. 380 and 381), closely
related to the Yuma variety (No. 382) are of interest as showing the
general excellence of this group. Both of these types are derived
from the same individual selection of 1906 which was the progenitor
of the Yuma variety. The progenitor of each was an individual
selection made in the same progeny row of 1907 in which plant 382
was selected. The progenies of the two selections of 1907 were
grown in rows in the breeding nursery at Yuma in 1908, and the
bulk seed from the unselected plants in each of these rows was used
for the plantings in 1909. One of these types (No. 384) was planted

200

NEW TYPES DEVELOPED. 19

near the town of El Centre in the Imperial Valley. California.
The plants were very uniform in branching habit and foliage and
showed only Egyptian characters, but one aberrant individual having
been found among the fifty or more plants in this plat. The fiber
was long, silky, and very strong — the best fiber of the Egyptian type
produced in the Imperial Valley in 1909. The other type (Xo. 380)
was planted in a test row at Yuma. The plants throughout the row
were productive and had long, pointed bolls and large bracts similar
to those of the Yuma variety. The seeds were generally smooth ; the
fiber averaged If inches in length and was silky, very strong, and
light colored.

PROBABLE MUTATIVE ORIGIN OF THE YUMA VARIETY.

The " Yuma " variety, type Xo. 382, was derived from imported
seed of the Mit Afifi Egyptian variety. Most of the strains which
have descended from the same original lot of seed are still typically
Mit Afifi in all their characters, as was evident from comparison with
plants grown from newly imported seed of that variety in 1908 and
1909. Nevertheless, this particular type now shows little resem-
blance to the parent variety. In the color of the lint it resembles
more nearly the Jannovitch variety. It is especially remarkable for
the long, taper-j)ointed bolls (PL III), which are much like those
of the Abbasi variety and are in marked contrast to the short, blunt
bolls of typical Mit Afifi (PL II). The manner of growth of the
j)lants, the characters of the foliage, and the large involucre bracts
are also diagnostic. The vegetative characters and the peculiarities
of the seed and fiber have recurred with conspicuous regularity
wherever seed of this variety or of nearly related types has been
planted. The distinctiveness of the characters and their remark-
able uniformity indicate that the variety originated as a mutation.0
The history of such Egyptian varieties as Abbasi and Jannovitch,
which are reported in Egypt to have developed from the widely
grown and older Mit Afifi variety, makes it altogether probable that

a The peculiar branching habit and foliage of the plants were not especially
noticed until 190S, when progeny row No. 382 was observed to stand out very
distinctively from all other rows in the breeding nursery. Yet the large size
of the bolls was noted as early as 1906 in the individual selection of that year,
from which this variety is descended. This, together with the close resem-
blance in the characters of the related type No. 380 (descended from the same
individual selection of 1906 which was the progenitor of the Yuma variety),
indicates that the mutation occurred at least as long ago as 1906. The incom-
pleteness of the records for the earlier years of this breeding work makes it
impossible to determine whether the actual mutation occurred earlier than 1906.
It is possible, although not probable, that it was present as an admixture in
the Mit Afifi seed imported from Egypt with which the work was begun in 1902.
200

20 BREEDING NEW TYPES OF EGYPTIAN COTTON.

they originated as mutations from that variety in the same manner
as the Yuma variety in this country.

THE SOMERTON VARIETY.

Type No. 370, here designated the " Somerton " variety, is remark-
able for the sharply defined characters of the plants and bolls, and is
like the Yuma variety in the great uniformity manifested in these re-
spects. It has not yet been adequately tested on a field scale, but the
progeny rows grown at Yuma and at Sacaton in 1909 showed it to
be a very distinct and definite type. It is being tested in field plant-
ings in 1910 in comparison with the Yuma variety.

HISTORY OF THE VARIETY PREVIOUS TO 1909.

The ancestry of the Somerton variety was similar to that of the
preceding down to the year 1905, when the individual plant selection
from which the Somerton variety is derived was made in the breeding
nursery at Carlsbad, N. Mex. This plant was fairly productive and
very early ripening and had small bolls and smooth seeds well covered
with lint (percentage, 33). The fiber was fairly uniform in length,
with an average of fully 1-J inches; it was brown in color, strong,
and very fine. In the 1906 progeny row at Yuma planted with seed
grown from this plant, the selected individual which was the progeni-
tor of the Somerton variety was a small, fairly well-shaped, very
productive, and early-ripening plant which had medium-sized bolls
and smooth seeds well furnished with lint (percentage, 30.5). The
fiber was 1J inches long, very uniform, light brown in color, strong,
and very fine. The 1907 progeny row from this plant was charac-
terized by exceptionally early ripening. One of the individual selec-
tions made in this row, No. 370, was the immediate progenitor of
the variety. It was an extremely productive plant, but the per-
centage of lint was only 26.5. The bolls were large ° and the fiber
was more than 1? inches in length, uniform, fine, fairly strong, and
cream colored.

Progeny row No. 370 contained in 1908 only 1.5 per cent of
hybrids, a remarkably small proportion as compared with most of
the other rows in the breeding nursery that year. (See footnote &,
page 12.) The plants in this row were large and very productive,
with a well-developed main stem surpassing the longest of the limbs.
The latter were spreading or ascending. The bolls were large and

° It will be noted that while the 1905 selection had small bolls and the 1906
plant only medium-sized bolls, the 1907 progenitor of this variety had large
bolls. While the bolls were increasing in size from year to year, the percentage
of lint was diminishing from 33 per cent in 1905 to 30.5 per cent in 1906 and
26.5 in 1907. (In regard to the decreased lint percentage, see p. 17.)
200

NEW TYPES DEVELOPED. 21

remarkably sharp pointed. The seed cotton from the unselected
plants in this row was picked and ginned together. The resulting
lint was light brown in color; that from the first two pickings was
classed by Mr. John A. Walker as " fine and strong " and that from
the third as "strictly fine, silky, and extra strong." In length of
fiber the first picking averaged If inches, the second ranged from
If to lT7e inches, and the third picking ranged from lT7y to 1-J inches.
The excellent luster of the fiber in this row was noted in the field.

The seed cotton from the ten individual selections of .1908 was
carefully compared. In seven of these the fiber was a little lighter
colored than imported Nubari cotton, in two the fiber was slightly
darker than imported Jannovitch, and in one the fiber was the same
color as Jannovitch. The extreme range of length among these ten
selections was from 1^ to If inches, but the fiber was generally at
least liV inches long. The average strength was inferior to that of
the selections from most of the other progeny rows of 1908. The
general appearance of the fiber was very similar in the ten selections
and indicated a distinct and uniform type. There was a strong
tendency to smooth seeds.

EXPERIMENTS IN 1909.

Eight of the selections from progeny row No. 370 of 1908 were
grown in progeny rows in 1909, six at Yuma and two at Sacaton.
The rows at Yuma when inspected by Mr. McLachlan on July 6
showed a higher degree of uniformity and a more distinctive type of
plant than any other group of progeny rows in the breeding nursery.
Only two of the rows showed any trace of contamination ; one con-
tained a single probable hybrid and another had two suspicious-
looking plants. The plants were bushy, large in diameter, with five
to eight limbs nearly as long as the main stem, the internodes of which
were unusually short. The leaves were exceptionally large and were
usually broader than long. They were five lobed, with deep clefts
between the lobes.a On July 23, when first inspected by the writer,
the plants in all the rows had an exceptionally vigorous appearance
and were distinguished by the unusually bright green color of the
foliage. The two progeny rows at Sacaton, inspected August 3.
showed the same type of plant and the same high degree of uni-
formity as the rows at Yuma. There were no obvious hybrids and
only one suspicious-looking individual in each row.

On September 23 the plants in the six rows at Yuma had grown
very large and were ripening late. The fruiting branches were set
well toward the base of the plant and were well furnished with bolls.

aA somewhat similar habit and type of foliage characterized the plants grown
at Yuma in 1909 from imported seed of the Nubari variety.
200

22 BREEDING NEW TYPES OF EGYPTIAN COTTON.

The seeds were generally smooth and rather poorly furnished with
lint.a Individual selections were finally made in only two of the
rows, the fiber in the other rows being too scanty and also inferior
in length. Numerous selections were made in the two rows at Saca-
ton, in both of which the plants were characterized by high average
fertility. The total number of individual selections of the Somerton
variety made in 1909 was twelve at Yuma and eighteen at Sacaton.

The seed cotton from all of the unselected plants in one of the
progeny rows at Sacaton was picked and ginned together. The lint
was light brown, corresponding in color with imported fiber of the
Xubari variety. The strength and diameter of the fiber were tested
by Mr. L. H. Dewey, who reported the average breaking strength as
6.3 grams (variation 3.6 to 11.5 grams) and the average diameter as 23
microns (variation 18.7 to 30 microns). This diameter indicates a
finer fiber than is shown by the fiber tests of the Yuma variety as
reported in Table I (p. 18).

Seed from the unselected plants in progeny row No. 370 of 1908
was planted in 1909 at Yuma, Ariz., and at Brawley, in the Im-
perial Valley. California. In the small planting at Yuma the plants
were of good average fertility, with generally large bolls and smooth
seeds. The fiber was satisfactory in length, reaching If inches on
many plants and falling below 1J inches on hardly any. It was of
good strength and medium fineness. In the 1-acre field planted with
this seed at Brawley the plants were very uniform in appearance,
and. with the exception of four hybrid individuals, showed only
pure Egyptian characters. The fruiting branches, which were well
furnished with bolls, were developed at low nodes on the stem. The
bolls were lars'e.

CHARACTERS OF THE PLANTS AND TIBER.

The Somerton variety as exemplified in the progeny rows at
Yuma and Sacaton in 1909 is characterized by a great spread of
branches, numerous long limbs, and long fruiting branches which
are developed well toward the base of the plant and bear numerous
bolls. The plants at about the time they begin to blossom have a
symmetrical, rounded, bushy appearance and are exceedingly leafy.
The large leaves are of a brighter green color and of softer texture than
in the Yuma variety. They are usually five lobecl and broader than
long, while in the Yuma variety they are generally three lobed and
considerably longer than broad. The bolls (PI. IV), which resemble

a The average percentage of lint obtained by ginning the seed cotton from the
thirty individual selections of the Somerton variety made at Yuma and Sacaton
was 25.1 per cent, as compared with 26.7 per cent for the thirty-nine individual
selections of the Yuma variety and 29.9 per cent for the eight selections of
strains Nos. 360 and 362.
200

NEW TYPES DEVELOPED. 23

those of the Abbasi Egyptian variety, are long and taper to an ex-
tremely sharp point, sharper than in the Yuma variety. The seeds
have a strong tendency to be smooth and are frequently devoid of
even the tuft of green or brown fuzz at each end which characterizes
the seeds of the Mit Afifi variety in Egypt, while in the Yuma varietv
the sides of the seeds are usually partly covered with fuzz. The lint
is very fine, but its percentage is less than in the Yuma variety. In
color it is usually darker, varying from that of the Jannovitch to
that of the Xubari varietv. It shows about the same rane;e of length
as that of the Yuma variety.

PERFORMANCE OF A NEARLY RELATED TYPE.

Seed from another individual selection from the same progeny
row of 1907 in which plant Xo. 370 was selected was grown at Yuma
in 1908. Seed from all the unselected plants in the 1908 row was
picked together and was used for planting a small plat in the neigh-
borhood of Los Angeles. Cal.. in 1909. alongside a similar planting
of imported seed of the Mit Afifi variety.0 The plants made only a
small growth, produced comparatively few bolls, and ripened very
late. On September 13. when none of the bolls had yet opened, no
difference could be detected between the plants from the acclimatized
and those from the imported seed, but in the quality of the fiber pro-
duced, the acclimatized ultimately proved very superior. The fiber
was fine and silky and excelled in strength any other cotton of the
Egyptian type grown in the Southwest in 1909. The average break-
ing strength, as reported by Mr. L. H. Dewey, was 8 grams (varia-
tion from 4: to 12 grams), and the average diameter 25 microns. As
compared with this the fiber produced by the plants from the newly
imported Mit Afifi seed in the same field was decidedly weaker and
coarser, its average breaking strength being 6.8 grams (variation
from 4 to 14.8 grams) and its average diameter being 30.6 microns.

PROBABLE MUTATIVE ORIGIX OF THE SOMERTOX VARIETY.

Like the Yuma variety the Somerton variety is very distinct from
the Mit Afifi stock with which this breeding work was begun and
shows a high degree of prepotency, as evidenced by the remarkable
uniformity which it has maintained notwithstanding abundant op-
portunities for crossing with other types. These facts give good

a This planting near Los Angeles, under the direction of Mr. O. F. Cook, was
made to ascertain the effect of very different climatic conditions upon the habit
of the plants and upon the expression of diversity in a stock that had been
acclimatized in the Colorado River region as compared with newly imported
seed. It was realized, of course, that the conditions in that part of California
are not favorable to cotton culture on a commercial scale.
200

24 BREEDING NEW TYPES OF EGYPTIAN COTTON.

ground for the belief that it has originated as a mutation. It is pos-
sible that the mutation occurred in 1907. since the breeding records
show that the 1905 ancestor of the strain had small bolls and the 1906
ancestor medium-sized bolls. The 1907 progenitor, which was the
first recorded as having large bolls, may well have been the original
mutant, but unfortunately no detailed description was made of the
vegetative characters of this plant. The plants of a nearly related
type grown near Los Angeles (p. 23) were so unlike those in any
planting of Egyptian types of cotton that has been made in the
Colorado Eiver region.0 that it was impossible to decide whether this
stock >hares the vegetative characters of the Somerton variety. If it
had been grown under similar conditions and had exhibited the same
characteristics, ample evidence would have been afforded that the
mutation must have occurred at least as early as 1906.

STRAINS NOS. 360. 3 61. AND 3 6 2.
ORTGIX OF THE GROVP.

The group of strains Xos. 360. 361. and 362. like the Yuma and Som-
erton varieties, was derived from an individual selection made at
Carlsbad. X. Mex.. in 1905, in a part of the breeding nursery where
the numbers of the progeny rows had been lost. The ancestry of
the group previous to 1905 is therefore unrecorded except that each
strain was derived from the same lot of imported Mit Afifi seed
used in beginning the breeding work in 1902. from which all the
varieties and strains described in this paper originated. An indi-
vidual selection in the progeny row from the Carlsbad plant grown
at Yuma in 1906 is the common ancestor of this group of strains.
The plants representing the progeny of the individual selected in 1906.
grown in a row at Yuma in 1907. were noted as being uniformly ex-
cellent. Three individual selections of that year, numbered as above.
are the direct progenitors of the three corresponding strains.

STRAIX NO. 3 60.

Selection Xo. 360 of 1907 was characterized by a satisfactory per-
centage of lint (30 per cent) and by fiber that was fully 1J inches
long, uniform in length, fine, and of a good brown color, but
rather inferior in strength. The 190S progeny row from this plant
contained about 11 per cent of hybrids. The remaining plants were

a The plants grown near Los Angeles, both from the acclimatized strain
and from imported Mit Afifi seed, were small, and they had few and short
limbs: they were conspicuously hairy and had a great deal of red color in the
stems and involucres. The bracts were broad, cordate, and deeply toothed.
The calyx was distinctly toothed, a character usually peculiar to Upland as
distinguished from Egyptian types. The stigmas were exceptionally short.
200

NEW TYPES DEVELOPED. 25

uniform and were typically Mit Afifi in their characters. They were
productive, ripened early, and produced fiber that was distinctly
brown in color. The seed cotton from the unselected plants in this
row was picked and ginned together. The lint had an average
length of If inches in the first picking and ranged from If to 1J
inches in the second picking. The strength and color were very
satisfactory in both pickings. Three individual selections were made
in this row, and the seed Avas planted in progeny rows in 1909, two
at Yuma and one at Sacaton. When examined July 6 one of the
rows at Yuma contained two and the other four unmistakable hybrid
individuals, and there was considerable diversity among the remain-
ing plants. The row at Sacaton, inspected August 3, contained no
obvious hybrids, but the plants were generally infertile, and the
row was discarded. In September one of the rows at Yuma was
decidedly inferior in the average length, strength, and fineness of
the fiber, and no selections were made; only one individual selection
was made in the other row at Yuma.

The seed cotton from the unselected plants in progeny row Xo. 360
of 1908 was picked and ginned together and the seed was planted at
Holtville, in the Imperial Valley, California, in 1909. The soil was
very sandy and the seed was planted late, consequently the yield was
small. ^Nevertheless, many of the plants showed a strong tendency to
produce a " bottom crop," developing fruiting branches at low nodes
on the stem. On a good percentage of the plants the fiber was satis-
factory in length and strength. There was considerable diversity in
the appearance and vegetative characters of the plants, and a large
number of hybrids and otherwise aberrant plants were ^removed at the
end of July.

STRAIN XO. 3 61.

History. — Individual selection Xo. 361 of 1907 was a much more
productive plant than Xo. 360, but otherwise greatly resembled it.
The seeds were abundantly furnished with lint, the percentage being
32. The fiber had all the characters of a good Mit Afifi and was very
fine, strong, and of a good brown color. The length exceeded 1\
inches and was very uniform. In 1908 the progeny row from this
plant contained about 6 per cent of hybrids. It was one of the most
uniformly fruitful and early-ripening rows in the breeding nursery.
The fiber was of typical Mit Afifi character, and was highly satisfac-
tory in fineness, color, and length, although the uniformity of length
was somewhat disappointing. The percentage of lint was good. All
seed from the unselected plants in this row was picked and ginned
together. Mr. John A. Walker reported on the lint from the first
picking that it has a "distinctly brown color. even throughout, showing
very little white, giving it a greater resemblance to regular Egyptian

200

26 BREEDING NEW TYPES OF EGYPTIAN COTTON.

(brown) than anything ginned to date; has also good lf-inch staple,
extra strong and silky. Can be regarded as very satisfactory cotton."
The second picking apparently contained a somewhat higher per-
centage of white fiber, but was otherwise similar. A careful exam-
ination of the seed cotton from eleven individual selections in this
row showed that in color it was slightly lighter than imported Xubari
fiber (footnote 5, p. 11) in all but two plants, in which is equaled
the Nubari. The selections were more uniform in their fiber char-
acters than those from most of the other progeny rows of 1908, the
uniformity having been especially marked in respect to color, strength,
and fineness.

Five progeny rows of strain No. 361 were grown at Yuma in 1909.
In all but one of the rows from one to three hybrid plants were found
on July G ; otherwise the plants were very similar in all the rows.
Unfortunately these five rows were planted in an unfavorable situa-
tion close to a row of cottonwood trees; they were consequently so
unproductive and the fiber was so short that no individual selections
could be made. The fiber showed more color than was exhibited in
the progeny rows of any other strain at Yuma in 1909.

Field test in 1909. — The bulk seed from the unselected plants in
progeny row Xo. 361 of 1908 was planted in 1909 in a field of 3 acres
near Yuma. On July 27, the evident hybrids having been roguecl out
early in the season, the field appeared very uniform. The plants
were rather strict in habit and did not develop fruiting branches at
the lower nodes,® which was doubtless chiefly owing to the rather late
planting and to lack of water for irrigation at critical times during
the summer. For the same reasons the yield from this field was low
and the lint was inferior in length and strength to what might have
been expected from the undoubted excellence of the stock. In dry
j^laces in the field the strength was especially inferior. There was
a marked tendency to uniformity in the characters of the plants and
fiber, and the percentage of probable hybrids or otherwise aberrant
individuals was small. The bolls held the ripe cotton better than
was observed with the Yuma variety. The fiber had an excellent
color, intermediate between that of Nubari and Mit Afifi (footnote
5, p. 11). A considerable number of typical plants in this field, dis-
tinguished from the average by greater fertility and better lint, were

a Mr. Argyle McLaclilan found that in fifteen representative plants from differ-
ent parts of this field the average lowest node of the main stem at which a
fruiting branch was developed was the fifteenth, hence not lower than in plant-
ings of imported seed of Egyptian varieties. On the other hand, in thirty
representative plants from different parts of the 4-acre field of the Yuma variety
the first fruiting branch was developed on the average at the tenth node of the
main stern. It should be observed, however, that the latter field was planted
three weeks earlier than the field of strain 361.
200

NEW TYPES DEVELOPED. 27

marked and the seed from these was picked together (bulk selection)
for planting a yield-test field in 1910. Ten individual selections were
also made by Mr. W. A. Peterson.

STRAIN NO. 3 62.

Individual selection No. 362 of 1907 was an exceedingly fruitful
plant, with a lint percentage of 29. The fiber was typically Mit Afifi
in character, had a good brown color, and was very fine in all but the
first picking.0 In length it exceeded 1J inches and showed a high
degree of uniformity. There was considerable variation in the
strength, the later pickings being inferior in this respect. The 1908
progeny row from this plant contained 7 per cent of hybrids. The
plants were very similar to those in row 361 (see above). They were
very productive and well shaped, with fruiting branches nearly to
the base of the stem. The bolls, which opened very early, varied
somewhat in size, but were generally medium sized for the Mit Afifi
variety. The fiber was of characteristic Mit Afifi type, very fine
and lustrous, strong, and well colored. There was a decided lack
of uniformity in length of fiber, but the average was about If inches.
The seed from the unselected plants in this row was picked and ginned
together. The lint was classed by Mr. Walker as " fine " in the first
picking and " strictly fine, silky " in the second picking. The length
ranged from 1J to If inches in the first and from If to 1 J inches in the
second picking. In both pickings the lint was " wasty." It was
" extra strong," but uneven in strength.

Seed cotton from eight individual selections from this row was
carefully examined, and proved very similar to that of the selections
in row 361. In color the fiber on four of the plants equaled imported
Mit Afifi, and on the other four equaled imported Xubari. The length
of the fiber on the different plants ranged from 1^ to lT9e inches, but
the average was 1T76 inches. The fiber was uniformly very fine and
generally strong. The lint percentage was good. The seeds varied
from smooth to partly covered with fuzz.

The seed of six individual selections was planted in progeny rows
at Yuma in 1909. TThen inspected on July 6 there were from one
to three evident hybrids in all but one of the rows, and there wa£
otherwise considerable diversity in foliage and branching habit. In
September the plants in all the rows appeared very similar in type
of plant and in the character of the bolls and lint. Eight individual
selections were made in the six rows.

a It was observed in 1908 that the fiber from the first picking in every lot of
cotton grown was coarser and rougher than that from the second and later
pickings. This was especially marked in early-ripening types, like No. 362,
and was doubtless due to the fact that the bolls opened and exposed the seed
cotton to the intense light and dry air long before the first picking was made.
200

28 BREEDING NEW TYPES OF EGYPTIAN COTTON.

GENERAL CHARACTERISTICS OF STRAINS NOS. 3 60, 3 61, AND 3 62.

The plants of strains Nos. 360, 361, and 362 grown in progeny
roAvs at Yuma in 1909 had an open habit (PL I, fig. 1) with a few
long, upright, slender limbs nearly equaling the main stem in length ;
the fruiting branches were long and slender, bearing comparatively
few bolls, and generally had a very long basal internode ; a the foliage
rather sparse ; the bolls short, rounded, and with a blunt tip (typical
Mit Afin bolls, see PL II) ; the seeds smooth or partly covered with
fuzz ; and the fiber generally short and strong, fine, and nearly as
brown in color as imported Mit Afin fiber. The percentage of lint
was much higher than in the Yuma and Somerton varieties, 25 pounds
of seed cotton from the " bulk selections " in the 3-acre field of strain
361 having yielded 31.6 per cent of lint.&

These strains constitute a uniform type which shows no marked
departure from typical Mit Afifi cotton as grown in Arizona from
imported seed, except that the j)lants are more productive and
develop fruiting branches at lower nodes on the stem, open their bolls
earlier, and produce lint of better quality. The high degree of uni-
formity exhibited by the plants in the 3-acre field of strain 361 at
Yuma in 1909 indicates a considerable degree of prepotency, since
the progeny row which produced this seed in 1908 was situated in
the breeding nursery among other rows of very different type, most
of which contained numerous mybrids (footnote 6, p. 12).

IMPORTED SEED OF EGYPTIAN VARIETIES TESTED IN 1909.

As a check on the progress of the acclimatization and selection and
in order to compare the amount and kinds of diversity shown by the
plants from newly imported seed with that of the acclimatized and
selected stocks, seed of the six leading Egyptian varieties (Mit Afifi,
Nubari, Jannovitch, Ashmuni, Abbasi, and Sultani) was planted in
alternate rows in the Yuma Valley and at Sacaton, Ariz. Larger
plantings (one-half acre to 1 acre) of the first four varieties were
also made in the Yuma Valley. A plat of imported Mit Afifi was

a This rather undesirable branching habit does not appear to be inherent in
these strains, but seems to be due mainly to the unfavorable situation of these
particular rows, which suffered several times during the season from lack of
moisture on account of the competition of a neighboring row of trees. In the
row which had the most favorable moisture conditions the plants were much
more productive, with fruiting branches developed well toward the base and
usually bearing five or six bolls each. In this row the bolls were larger than
in the others.

6 Mr. Argyle McLachlan found that 100 delinted seeds of strain 361 weighed
11.75 grams, while the same number of seeds from a sample of imported Mit
Afifi weighed only 10 grams. If the seeds weighed no more than the imported
(see p. 17), the lint percentage of strain 361 would therefore have been 35.3
instead of 31.6.
200

MISCELLANEOUS EXPERIMENTS IN 1909. 29

also grown alongside a planting of a select acclimatized stock derived
from the same variety at Glendale, near Los Angeles, Cal. (See
p. 23.)

The imported varieties differed widely in the amount of diversity
shown, this being least in the Mit Afifi and Xubari varieties and
greatest in Ashmuni. The Mit Afifi and Nubari varieties showed a
high degree of uniformity, indicating that the seed received from
Egypt was the result of careful selection in that country. The Mit
Afifi, as in all previous plantings of imported seed of that variety,
at all places where the comparative plantings were made, showed
itself very inferior to the acclimatized and selected stocks in yield,
earliness, and quality of the fiber. On the other hand, the Nubari,
although by no means equaling the* improved strains which have
resulted from several years of acclimatization and selection in the
Southwest, was decidedly superior in all these respects to any other
planting of newly imported seed which has been made in that region.
The yield from one-half acre of this variety was 514 pounds of seed
cotton, which was equivalent to 290 pounds of lint per acre, the per-
centage of lint being 28.1.

MISCELLANEOUS EXPERIMENTS IN 1909.

In addition to the plant-breeding experiments and the field tests
of acclimatized and imported stocks, a number of other experimental
plantings were made near Yuma, Ariz.

Progeny of first- generation hybrids. — Progeny rows of several first-
generation Upland-Egyptian hybrids selected in the breeding nurs-
ery of 1908 (see footnote b: p. 12) were grown. It was observed in
1908 that these first-generation hybrids, when compared with the
pure Egyptian plants in the rows in which they occurred, were very
superior in fruitfulness, size of bolls, and in the abundance, length,
and strength of the fiber. The progenies of the different individuals
in 1909 showed considerable difference in the amount of diversity and
m the degree in which the characters of the Egyptian or of the
Upland parent predominated. Xone of the plants in any of the rows
came near equaling the parent selections in productiveness or in the
quality of the fiber. Some of the first-generation hybrid parents had
very smooth seeds and others had completely fuzzy seeds. As a rule,
the progenies in 1909 showed no uniformity in their inheritance of
this character ; many fuzzy-seeded offspring were from smooth-seeded
parents, and vice versa. An examination of these hybrid progeny
rows gave no indication of the likelihood that a superior strain could
be developed by this method, and no selections were made in the
second generation.

Production of first- generation hybrids. — Under the direction of
Mr. O. F. Cook, Egyptian cotton was planted in rows alternating

200

30 BREEDING NEW TYPES OF EGYPTIAN COTTON.

with various Upland varieties in order to test the possibility of secur-
ing in this manner a stock of first-generation hybrid seed for com-
mercial planting." The early flowering of most of the Upland varie-
ties, as compared with the Egyptian, indicated that to use this
method successfully it might be necessary to select a late-flowering
Upland variety for the alternate plantings or else to plant the Up-
land cotton later than the Egyptian.

Seed selection. — Another experiment, carried on by Mr. Argyle
McLachlan, was the planting in separate rows of the different types
of seed selected from various imported and acclimatized lots, in
order to determine the possible advantage of sorting by hand cot-
ton seed that has become mixed by hybridization, and thus to elimi-
nate aberrant types before planting, thereby gaining greater uni-
formity in the crop and reducing the opportunity for further crossing.

Different dates of planting. — Row plantings of a single acclima-
tized stock were made on successive dates throughout the spring in
order to compare the effect of early with that of late planting under
otherwise uniform conditions upon the fruitfulness and lint quali-
ties of the plants, and to ascertain the best time for putting in the
seed. For various reasons this experiment gave no conclusive results,
but the matter is an important one and will be made the subject of
further experimentation. All the evidence so far obtained points to
the advantage of planting Egyptian cotton in the Colorado River
region as early in the spring as the weather will permit.

Seed from different pickings. — Seed from the different pickings of
several of the acclimatized stocks was planted in rows in order to
determine if possible whether the early or the late ripened seed is
the most desirable for planting. Only negative results were ob-
tained, none of the three pickings appearing to give generally better
results than either of the others, but it is not considered that this
problem has been finally solved.

Irrigation. — The conditions in 1909 with regard to the supply of
water for irrigation were so unfavorable that no special experiments
could be carried out to determine the best method of irrigating Egyp-
tian cotton. There is no question that the yield, uniformity, and
quality of the fiber, especially in respect to length and strength,
depend in a high degree upon the manner in which the plants are
irrigated. This is considered the most important cultural problem
remaining to be solved in connection with the production of this crop
in the Southwest.

"In a paper entitled " Suppressed and Intensified Characters in Cotton
Hybrids," Bulletin 147, Bureau of Plant Industry, United States Department
of Agriculture, pp. 15-16, Mr. Cook calls attention to the possible commercial
utilization of the superior qualities of first-generation hybrids of Egyptian with
Upland cotton.
200

COMMERCIAL STATUS OF EGYPTIAN COTTON.

31

PRESENT COMMERCIAL STATUS OF EGYPTIAN COTTON IN THE

UNITED STATES.

During the latter part of 1909 and the early months of 1910 all types
of cotton commanded unusually high prices. The condition of the
long-staple cotton market was especially abnormal owing to the opera-
tion of a number of independent causes. The advance of the boll weevil
in the cotton belt of the South has led to a feeling of uncertainty in the
localities which furnish the bulk of our supply of long-staple Upland
cotton. Furthermore, the 1909 crop in Egypt was an exceptionally
small one, and from all reports the quality of the fiber was unusually
poor. Various explanations are offered for the disquieting state of
affairs that exists in Egypt. It is widely believed that the construction
of the great dam at Assuan, in upper Egypt, and of " high line " canals.
with the consequent abundance of irrigating water and increased
opportunity for seepage, has resulted in raising the water table
throughout the cotton-growing provinces of the Delta to a point that
seriously injures the deep-rooted cotton plants.

Table II. — Average prices of Good Fair Egyptian and Middling Upland cottons
on the Boston market for each month from January to October. W09.a

Month.

Average price per
pound.

Month.

Average price per
pound.

Good Fair
Egyptian.

Middling

Upland.

Good Fair
Egyptian.

Middling
Upland.

Cents.

17.0
16.5
16.0
16.6
18.0

Cents.

*9.9

9.9

9.9

10.5

11.3

■

Cents.
18.5

19.9

Cents.

11.5

July

12.9

19.9

12.7

April

May

September > 20.2

October

13.2
14.4

" The average prices of Egyptian and Middling Upland cottons on the Boston and Liver-
pool markets during the ten years from 1898 to 1907, inclusive, are stated in Bulletin
12S, Bureau of Plant Industry. P- 25, tables 4 and 5. Prices during 190S are discussed
in Circular 29, Bureau of riant Industry, pp. 5 and 6.

Table III. — Average prices of different grades of Egyptian and of Middling
Upland cotton on the Boston market for each month from November, 1909, to
July. 1910.a

Average price per

pound.

Egyptian.

*

Low
grades.

Current.

Good

grades.

High

grades.

Middling
Upland.

Cents.

19 -224.

22^-25i

24 -26|

22 -27

221-28i

204-27#

19l-22f

172-22!

17i-20i

Cents.

20i-23f
24 -274
251-281
26 -32
274-334
23f-321
23±-26±
19J-26£
19i-212

Cents.
21f-25|

26 -29^

27 1-30 §

28^-33

324-34i

28i-33i

26|-30|

21J-30I

20I-22J

CenU.

23 -274

27J-31

29^-32}

311-35^

33i-36|

314-361

291-33

22|-33

212-244.

Cents.
15 -15|

December, 1 90y

15 -15|

Januarv, 1910

Februarv, 1910

March , 1910

April, 1910 . '.

15 -16f
15^15^
loyg-loA
15i^-15&

May, 1910

June, 1910

15&-15H
14| -15±

Julv, 1910

15* -16

a The prices for each month are the minimum and the maximum of the weekly prices
for each grade as quoted in the Commercial Bulletin, published at Boston.

200

32 BREEDING NEW TYPES OF EGYPTIAN COTTON.

It would be unwise to rely upon a maintenance of the recent very
high level of prices. During the ten years from 1898 to 1907. in-
clusive, the average price on the Boston market of all grades of
Egyptian cotton imported was 15.3 cent?, as compared with 0.5 cents
fur Middling Upland. During 190S the average price of Egyptian
cotton on the same market was 18.07 cent-, as compared with 11.11
cents for Middling Upland. It should be noted, however, that these
prices cover the total quantity of Egyptian cotton imported, much of
which belongs to very inferior grades. Fiber of a quality such as
experiments have demonstrated can be produced in the Southwest
would be expected to command a premium of several cents over the
average.

The total imports of Egyptian cotton into the United States during
the calendar year 1909 amounted to 72.617. 893 pounds, valued at
$12,101,000, as compared with 61,511,723 pound-, valued at $11,-
560,009, in 1908.

CONCLUSION.

In summing up the most important results of the breeding work
with Egyptian cotton in 1909. it is noted that the diversity caused
largely by crossing with other types of cotton, which in 190S seemed
to seriously threaten the future of the acclimatized stock, has to a
great extent disappeared. This is doubtless partly due to the plant-
ing of carefully selected types. The most promising of these is
apparently a mutation and -hows a strong tendency to be prepotent:
in other words, to maintain its uniformity even in the presence of
opportunity for crossing with other stocks". The application of
methods of eliminating hybrids and aberrant individuals before the
plants begin to open their flowers which Mr. Cook has worked out
as a result of his diversity studies has also greatly contributed to this
result.

The breeding work of the past -even years has developed several
superior -trains and two very distinct varieties which are now ready
for testing on a field scale. The two varieties — the Yuma and the
Somerton — developed from an imported stock of the Mit Ann vari-
ety, represent a wide departure from the characteristic parent type.
In their large, pointed bolls and lighter colored fiber they more nearly
approach other Egyptian varieties, which are also believed to be de-
rived from Mit Afifi and probably originated in the same manner
as " sports " or " mutations." One of the new strains represents typ-
ical Mit Afifi in the shape of its bolls and in the deeper color and other
characteristics of its fiber, but is notably superior to the average of
that variety, at least as grown in the United States from imported
seed. This -train, which was grown last year on a field scale, like-
wise exhibited a high degree of uniformity.

200

SUMMARY. 33

Experiments in 1909 with these well-marked new varieties indicate
that transfer to a new locality having somewhat different climatic
and soil conditions does not induce diversity to anything like the
extent that results when newly imported seed or mixed seed of dif-
ferent acclimatized stocks is planted in new places. Thus the very
distinct Yuma variety, which was first distinguished and very likely
originated at Yuma, Ariz., maintained its superior uniformity, pro-
ductiveness, and distinctive type of plants and of fiber when planted
under the decidedly different conditions existing at Sacaton, Ariz.,
and in the Imperial Valley, California. The equally distinct Som-
erton variety, which also probably originated near Yuma, maintained
its superiority to newly imported seed at Sacaton and at Los Angeles,
Cal., although in the latter locality, which represents an extreme de-
parture from the climatic conditions existing in the Yuma Valley,
the general appearance of the plants was very different. It is there-
fore apparent that the difficulties of " local adjustment " or adapta-
tion of an acclimatized strain to the varying climatic and soil condi-
tions of different localities in the region in which the acclimatization
has taken place are not likely to interfere seriously with the extensive
utilization of selected types possessing a high degree of prepotency
such as are described in this paper.

SUMMARY.

Several distinct and promising varieties and strains which have
resulted from the acclimatization and breeding experiments with
Egyptian cotton in the southwestern United States were tested on a
field scale in the Colorado River region in 1909 and gave very favor-
able results in regard to the quality and uniformity of the fiber
produced.

The results of the season's work showed that by planting carefully
selected types and by " roguing out " the markedly aberrant indi-
viduals early in the summer the degree of uniformity can be attained
which is demanded by the market for this class of cotton.

Diversity can be still further controlled and the fruitfulness of the
plants maintained by avoiding extremely light and extremely heavy
types of soil and by managing irrigation so that the plants are not
exposed to alternations of severe drought and excessive moisture.

Samples of the fiber produced in 1909 were submitted to a number
of spinners and other experts, who were unanimous in pronouncing
them equal in all respects to imported Egyptian cotton of correspond-
ing grades.

Two of the best types (the Yuma and Somerton varieties) are so
distinct from the Mit Afifi variety from which they have been derived
as to warrant the belief that they are mutations and have originated

200

34 BREEDING NEW TYPES OF EGYPTIAN COTTON.

in the same manner as Abbasi. Jannovitch. and other superior types
which have been developed in Egypt from the Mit Afifi variety.

A third type j strains B603 361, and 3'32 | resembles Mit AM in all
characters of the plants, bolls, and fiber, but the plants are much
more productive and produce fiber of better quality than those grown
in the same region from imported seed. This type is to be regarded
as an acclimatized and improved Mit Afifi rather than a new variety.

The Ytima variety was tested in a field of -1 acres near Yuma. Ariz..
in 1909. and showed a very satisfactory degree of uniformity in the
productiveness and habit of the plants and in the quality of the fiber.
It is characterized by a strong tendency to develop a stout main stem
greatly surpassing the limbs, and possesses long fruiting branches,
long taper-pointed bolls, and strong, silky, cream-colored fiber,
averaging about 14 inches in length.

The Somerton variety resembles the preceding in the length of its

bolls and in most of its fiber characters, but the bolls are more sharply

pointed, the seeds generally smoother, the percentage of lint smaller.

the plants more bushy, with a greater development of large

vegetative branches.

The group of strains Xos. 360, 361. an 1 362 nstitutes a uniform
type that i- very different from the Yuma and Somerton varieties.
The plants f open habit, with several large limbs nearly equaling

the main stem : short, plump, abruptly pointed bolls : and strong fiber
of medium length i averaging 1^ to If inches ) . In color the fiber is
almost as brown as that of imported Mit Afifi.

Other more or less distinct type- have been developed, but are either
I tisfactory or have not yet been sufficiently tested.

Import Is I of the principal Egyptian varieties was planted

in 1909 in Arizona in the vicinity of Yuma and at Sacaton. The

-ties differed greatly in the amount of individual diversity mani-

- ed. Xone of them equaled the acclimatized stocks in fruitfulness
or in quality of the lint.

Progenies of a number of first-generation Egyptian-Upland hy-
brids were grown near Yuma. The second-generation plants showed
excessive diversity of type, but none of them could compare with the
first-generation parents in yield or in excellence of the fiber.

The imports of cotton from Egypt into the United States during
the calendar year 1909 amounted to 72.617.^93 pounds, valued at
$12,11 L, . a- compared with 61.511. 723 pounds, valued at $11,-
. in 1908.
...

PLATES

200

35

DESCRIPTION OF PLATES.

Plate I. Fig. 1. — A fertile plant of acclimatized Egyptian cotton of the type
characteristic of strains Nos. 360, 361, and 362, with several large ascending
vegetative branches nearly as long as the main stem and bearing a con-
siderable percentage of the bolls. Grown near Yuma, Ariz., in 1908. Fig.
2. — A plant of the Yuma variety of acclimatized Egyptian cotton with a
tall, stout main stem bearing most of the bolls and with the vegetative
branches much reduced. Grown near Yuma, Ariz., in 1908.

Plate II. Typical bolls and bracts (natural size) of Mit Afifi Egyptian cotton
grown from imported seed near Yuma, Ariz., in 1908.

Plate III. Typical bolls and bracts (natural size) of the Yuma variety of accli-
matized Egyptian cotton grown near Yuma, Ariz., in 1909. Note the larger
and more pointed bolls as compared with typical Mit Afifi (PI. II).

Plate IV. Typical bolls and bracts (natural size) of the Somerton variety of
acclimatized Egyptian cotton grown near Yuma, Ariz., in 1909. The bolls
are more sharply pointed than in the Yuma variety (PI. III).
200
36

Bui. 200, Bureau of Plant Industry, U, S. Dept. of Agriculture.

Plate I

Fig. 1 .— A Fertile Plant of Acclimatized Egyptian Cotton.

Fig. 2.— A Plant of the Yuma Variety of Acclimatized Egyptian Cotton.

Bui. 200, Bureau of Plant Industry, U. S. Dept. of Agriculture.

Plate II.

Typical Bolls and Bracts of Mit Afifi Egyptian Cotton Grown from Imported

Seed.
(Natural size.)

Bui. 200, Bureau of Plant Industry, U. S. Dept. of Agriculture.

Plate III.

Typical Bolls and Bracts of the Yuma Variety of Acclimatized Egyptian Cotton.

(Natural size.)

Bui. 200, Bureau of Plant Industry, U. S. Dept. of Agriculture.

Plate IV.

Typical Bolls and Bracts of the Somerton Variety of Acclimatized Egyptian

Cotton.

(Natural size.)

INDEX

Abbasi cotton. See Cotton, Egyptian, varieties. page

Acclimatization, results of investigations. '. 7, 17, 23, 28, 29, 33

Arizona, cotton grown, quality 9, 29, 34

tendency to intercross ] 2-13

Ashmuni cotton. See Cotton, Egyptian, varieties.

Assuan, Egypt, construction of dam, effect on cotton crop 31

Bees, activity in pollination of cotton 13

Bolls of cotton, indicative of types 11, 18, 22, 28, 34, 36

Branches of cotton, fertile and vegetative distinguished 10-11

Branching, type indicative of character 10-11, 17, 22, 28, 34, 36

Brawley, Cal., cotton experiments 22

Breeding, plant, importance of early examination of cotton rows 11

location of plats .' 8, 9

methods 10-13

summary of results 32-34

Carlsbad, N. Mex., cotton experiments 9

Climate, factor in plant breeding 12, 23, 33

Color of fiber. See Fiber.

Colorado River region. See Experiments at Yuma and in the Imperial Valley.

Conclusion and summary of bulletin 32-34

Cook, O. F., cotton investigations " 7, 9, 10, 11, 17, 23, 29, 30, 32

Cooperation with Office of Indian Affairs 7-8

Reclamation Service 7-8

Cotton, Egyptian, development of new types 9-28

imports, 1909 32, 34

present commercial status in the United States 31-32

prices, Boston market 31-32, 34

tests of seed in 1909 28, 29

types, No. 300 12

300 to 340, origin 12

301 12

320. : 12

330 12

340 12

350 12

350 to 390, origin 12

360 12, 22, 24-25, 28, 34, 36

361 8, 12, 24-28, 34, 36

362 12, 22, 24, 27, 28, 34, 36

363 12

370, numerical designation of Somerton variety. . 20

380 12, 18, 19

382, numerical designation of Yuma variety 13

384 18

390 12

200 37

38 BREEDING NEW TYPES OF EGYPTIAN COTTON.

Page.

Cotton, Egyptian, varieties, Abbasi 11, 23, 28

Ashmuni 28, 29

Jannovitch 11, 14, 15, 18, 19, 21, 23, 28, 34

Mit Ann 8, 0, 11, 17, 23, 24, 28-29, 32-34, 36

Nubari 11, 21, 28, 29

Somerton 20-24, 32-34, 36

Sultani, imported for test 28

Yuma 13-20, 32-34, 36

experiments. See Experiments.

in Egypt, conditions affecting crop 31

Upland, growth at Yuma 12, 16, 30

prices, Boston market 31-32

See also, Acclimatization, Bolls, Branches, Branching, Breeding, Experi-
ments, Fiber, Foliage, Fuzz, Hybrids, Irrigation, Mutations, Seed, Yield, etc.

Culture, study of methods 7-8

Dewey, L. H., tests of lint 18, 22, 23

Egypt, construction of Assuan dam, effect on cotton crop 31

cotton crop in 1909 31

Egyptian cotton. See Cotton, Egyptian.

El Centro, Cal., cotton experiments 19

Experiments, cotton, at Yuma, Ariz 8, 9, 12, 13, 15, 16, 18-29, 33, 34, 36

in the Imperial Valley 8, 19, 22, 25, 33

methods of selection 10-13

miscellaneous 29-30

new types developed 8-28

Fiber of cotton, color determinations 11

quality determinations 13-15, 18-29, 32-34

Foliage of cotton, indicative of types 15, 16, 18, 19, 21, 22, 27, 28

Fuzz, development on seeds of American-grown cotton 11, 15, 18, 23, 27, 28, 29

Glendale, Cal., cotton experiments 8, 29

Holtville, Cal., cotton experiments 25

Hudson, E. W., cotton cultural work at Sacaton, Ariz 8

Hybridization of cotton, precautions to prevent 12-13

Hybrids among cottons under investigation 12-29, 34

first generation 12, 29, 34

Imperial Valley, Cal. See Experiments in the Imperial Valley.

Insects, activity in pollination of cotton 13

Intercrossing of cotton, precautions to prevent 12-13

Introduction to bulletin 7-9

Irrigation, factor of cotton investigations 7, 30, 33

Isolation to prevent intercrossing 12-13

Jannovitch cotton. See Cotton, Egyptian, varieties.

Kearney, T. H., and Peterson, W. A., on experiments with Egyptian cotton. . 7

Length of cotton fiber. See Fiber.

Limbs, definition of term as applied to cotton plant 10-11

Lint. See Fiber.

Los Angeles, Cal., cotton experiments 8, 23, 24, 29, 33

Luster of fiber of cotton, notable in Somerton variety 21

McLachlan, Argyle, observations 7, 15, 16, 17, 21, 26, 28, 30

Meade, R. M., on results of investigations 7

Mit Afifi cotton. See Cotton, Egyptian, varieties.

Mutations, origin of new varieties of cotton.. 19-20. 23-24, 32, 33-34

200

INDEX. 39

Page.
Nubari cotton. See Cotton, Egyptian, varieties.
Office of Indian Affairs. See Cooperation.

Seed and Plant Introduction, importation of cotton seed 9

Peterson, W. A., and Kearney, T. H., on experiments with Egyptian cotton. . 7

experimental cotton work at Yuma, Ariz 8, 27

Pickings of cotton, comparisons, experiments covering 30

Pima Indian Reservation. See Sacaton, Ariz.
Plant-breeding investigations. See Breeding.

Planting of cotton, different dates 30

Plates, descriptions ". 36

Pollination of cotton, unusual factors in Arizona 13

Prepotency, evidences of tendency in cotton 12, 16

Reclamation Service. See Cooperation.

Records of cotton strains 350 to 390, loss at Yuma 12

Ridgway, Robert, on colors 11

Roguing of cotton, application of method 8-9, 32, 33

Sacaton, Ariz., cotton experiments 8, 9, 12, 15, 16, 18, 20-22, 25, 28, 33, 34

Seed of cotton, comparison of different pickings 30

imported, tests in 1909 28

selection 30

Selection, use of method in cotton breeding work 9-13, 30

Soil, factor in plant breeding 12, 16, 25, 33

Somerton, Ariz., cotton experiments 8-9

variety of cotton. See Cotton, Egyptian, varieties.

Strain of cotton, definition 9

Strength of fiber. See Fiber.

Sultani cotton. See Cotton, Egyptian, varieties.

Summary of bulletin 33-34

Tests of imported cotton seed, 1909 28

Time of planting cotton, experiments covering 30

Types of cotton, new, developed 9-28

Variety of cotton, definition 9

See also Cotton, Egyptian, varieties.

Walker, J. A., on grades of cotton 14,21,25,27

Yield of cotton in 1909 16

Yuma, Ariz. See Experiments.

Valley. See Experiments at Yuma, Ariz.

variety of cotton. See Cotton, Egyptian, varieties.
200

o