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1987 ANNUAL REPORT

pe USDA-ARS
BIOLOGICAL CONTROL Or WEEDS
LABORATORY — EUROPE

RoME- ITALY

4 a he

BIOLOGICAL CONTROL OF WEEDS LABORATORY PERSONNEL

Paul H.. Dunn Research Entomologist, Research Leader

Pasquale Pecora Research Entomologist

Luca Fornasari Research Entomologist

Gaetano Campobasso ; Agricultural Research Assistant

Massimo Cristofaro Agricultural Research Clerk

Massimo Stazi Agricultural Research Clerk

Claudine Vincenti Administrative Clerk

Antonio Laregina Botanical. Technician

Rouhollah Sobhian Research Entomologist, American Embassy,
, Vienna, Austria, and Thessaloniki, Greece

Antonio. Taricone ’ Part-time Maintenance Man

Anna Claudia Pastorino PIT Laboratory Assistant

Pierluigi De Luca 4 .- ++ PIT Summer Helper

Cover photograph

By Tim McCabe, Information Service, ARS, USDA, Beltsville, Md.

Oxycesta geografica
(Lepidoptera: Noctuidae)

‘This moth was found in Romania. The female lays her eggs on the underside of a
leaf of Euphorbia virgata W. et K, and the neonate larvae move to the top of
the plant and make a silken tent which increases in size as the larvae grow.
The later instar larvae feed outside of the tent, but return to the tent to
rest. As the larvae mature they completely defoliate the plant on which the
eggs were laid as well as adjacent plants. The mature larvae migrate away from
the plants on which they have fed and pupate in dried leaves and plant trash.

NOT FOR PUBLICATION
NOTICE

The results of this report are preliminary and should not be quoted or
discussed in publications without permission of the responsible scientist. If
there is need to refer to this work, please correspond with the scientist and
include a copy of the pertinent portion of your manuscript. The work should
be cited as a personal communication and not in a bibliography. This report
has an extremely limited distribution and is intended only to provide a means
of communication among scientists and to provide a historical record of our
laboratory. :

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TABLE OF CONTENTS

INTRODUCTION page

ROME

LEAFY SPURGE (Euphorbia virgata spp. complex W. et K.)
Simyra dentinosa Freyer
Chamaesphecia sp. Bartel
Dasineura sp. nr. capsulae Kieffer
Aphthona | abdominalis Duftschm.
Collection and Survey Trips

YELLOW STARTHISTLE (Centaurea solstitialis L.)
Eustenopus villosus (Boheman

Collection and Survey Trips

DIFFUSE KNAPWEED (Centaurea diffusa Lam.)
Bangasternus fausti Reitter
Aceria centaureae (Nal.) (Petiton to import into quarantine)

GREECE (R. Sobhian)

LEAFY SPURGE (Euphorbia virgata spp. complex W. et K.)
Simyra dentinosa Freyer

YELLOW STARTHISTLE (Centaurea solstitialis L.)
Bangasternus orientalis Capiomont
Larinus curtus Hochhut
Eustenopus villosus (Boheman)
Chaetorellia hexachaeta Loew.

DIFFUSE KNAPWEED (Centaurea diffusa Lan.)
Bangasternus fausti Reitter

Pterolonche inspersa Stgr.
Aceria centaureae (Nal.)
Exploration
Miscellaneous
Shipments (insects, plants, plant parts)
PUBLICATIONS (ROME AND GREECE)
TRAVEL (ROME)
SHIPMENTS (ROME)
VISITORS (ROME)
INSECTS SENT FOR IDENTIFICATION

DISTRIBUTION LIST OF ANNUAL REPORT (PARTIAL)

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INTRODUCTION

The year 1987 was an active year for the Rome laboratory and good progress
was made toward clearing a number of natural enemies for release in 1989
through 1991.

In addition to the screening program a lot of effort was put into
collecting insects already cleared for release and colonization. A brief
overview of the activities associated with each target plant shows that the

_following collections were made for sending to the U.S. against the named

target plants.

Leafy spurge: Aphthona cyparissiae, Aphthona flava,
Aphthona czwalinae, Bayeria capitigena,

Oberea erythrocephala

Yellow starthistle: Bangasternus orientalis
Diffuse knapweed: Pterolonche inspersa
Convolvulus arvensis: Tyta luctosa

More importantly, there are a substantial number of insects in the
"pipeline" being cleared for introduction. This is an impressive list and
clearly indicates where the bulk of our research is concentrated. We are
currently working on clearing 12 arthropods and all of them are promising
candidates. A list of the target weeds, the natural enemies being screened
for their control, and the probable release date of these natural enemies

follows:

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WEED CANDIDATE NATURAL ENEMY PROPOSED

RELEASE DATE

Leafy spurge Aphthona abdominalis 1989
Chamaesphecia crassicornis 1989
Dasineura sp. 1989
Oxycesta geographica 1990
Simyra dentinosa 1989
Diffuse knapweed Bangasternus fausti 1989
Aceria centaurea 1990
Larinus minutus u 1989
Yellow starthistle Eustenopus villosus 1989
Larinus curtus 1991
Musk thistle Psylloides chalcomera 1989
Cheilosia corydon 1991

If our research program runs smoothly in 1988 and there are no surprises
it is conceivable, even possible, that 8 natural enemies will be ready for
release in 1989, another 2 in 1990 and another 2 in 1991, all against the
target weeds in our current list.

A new set of target weeds must be selected soon so the preliminary
library, herbarium, museum work and exploration can be started so the weeds
and candidate insects can be found and research started on these new insects
to replace those which are now in the process of being cleared for

introduction.

7, This is a Canadian project, financed by Agriculture Canada with CIBC
Delémont. We have a cooperative field trial in Thessaloniki, Greece being

conducted by Delémont and ARS (Sobhian) personnel.

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This is my 7th and last annual report because I am retiring shortly.
Preparing the annual report has never been my favorite occupation but ina
good year it provides a lot of satisfaction after it has all come together and
we can see the progress we have made during the year. This is the staff's and
Research Leader's opportunity to let our administrators see what they got and
what they are going to get for the support they have given us. When I look
back at this preface and the contents of the report, I feel like by leaving I
am jumping out of a moving train and have a vague feeling that I would like to
stay on board until we arrive at our destination and clear 4 or 6 or 8 insects

for release. This will be done, I just won't be on board.

It has been an interesting trip with great traveling companions and lots
of adventures and hard work. I want to thank all of you, (you know who you

are), who made these last 7 years an unforgettable experience.

Paul H. Dunn,

Director.

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LEAFY SPURGE PROJECT 1987

(P. Pecora, L. Fornasari, M. Cristofaro, M. Stazi)

Simyra dentinosa Freyer (Lepidoptera: Noctuidae)
Pasquale Pecora and Massimo Cristofaro

BIOLOGY NOTES

Adult emergence of Simyra dentinosa was recorded from 41 pupae, 21 of
which were individually distributed into 250 cc. cardboard containers and kept
in an outdoor insectary, and 20 were removed from their cocoons and put (10
each) into two plastic containers (15 x 15 x 20 cm.), buried within (6-8 cm.)
cornmeal. These containers were kept in a controlled temperature cabinet
(15 + 1°C.) from mid-June until early November and then moved to the outdoor
insectary until adult emergence was completed.

From the 21 pupae kept out-of-doors, 13 adults (8 females, 5 males) (62%)
emerged during the second half of April; 4 (30%) of these had malformed
wings. From pupae kept in cornmeal, 12 adults (5 females, 7 males) emerged in
the last week in April and 7 (58.3%) were malformed. In the laboratory adults
survived 4-10 days, sitting for hours on cage walls or on a plant with no
activity. No mating was observed.

Thirty eggs, collected on Buphorbia seguierana at Volvi Lake on April 5,
1987, were measured for size (diameter only). Also, the pre-eclosion period
and the percentage of egg fertility were recorded on a sample of 150
field-collected eggs, kept in an outdoor insectary.

The eggs, which were relatively flat, disclike, nearly circular, measured
0.87 + 0.05 mm. (n=30) in diameter (range = 0.76-0.96 mm.). They were light

yellow when first laid and turned dark brown in 3-5 days. The eggs were laid

3
in masses in nee e regular rows on the underside of single leaflets of
E. seguierana. The number of eggs/mass ranged between 61-241 (n=28). The
pre-eclosion period of 150 fresh laid field collected eggs, kept in a
laboratory room (temp. 20° + 3°C.) ranged from 16-19 days, and 95% were

fertile.

HOST SPECIFICITY TESTS

The test conducted in 1986 showed that S. dentinosa larvae could develop
only on plants in the genus Euphorbia. In 1987 host specificity studies were
completed on plants recorded in the literature as being attacked by other
Simyra spp., i.e. Triticum aestivum L., Secale cereale L., Phalaris
canariensis L., Poa pratensis L., Dactylis glomerata, Zea mays L. (sweet corn)
(Gramineae), Rheum rhabarbarum (Polygonaceae), Typha latifolia L.,
(Typhaceae), and several ornamental plants representing related superorders.
These were: Sedum album L. (Crassulaceae), Helianthemum apenninum L.
(Cistaceae), Fagopyrum tataricum (L.) Gaertn.; Asclepias syriaca L., A.
speciosa Torr. (Asclepiadaceae); Alyssum argenteum All. (Cruciferae), Iris
sibirica L. (Iridaceae).

Two larval survival tests were set up by using neonate larvae from eggs
collected near Volvi Lake (Greece) on E. seguierana at the beginning of April
1987. In one experiment (Test A) single first instars were tested, using 10
larvae for each plant species. Each larva was placed in a 500 cc. cardboard
cup which had a folded paper towel on the bottom to absorb any water and was
covered with a plastic lid in which a 5 cm. diameter central hole had been
made, and covered with nylon organdy to allow air exchange. A bouquet of
fresh leaves of the appropriate test plant was placed in the cup, and was

inspected and replaced twice weekly. At each inspection, the number of living

6
and dead larvae was recorded, and the amount of feeding was measured in mm“
by using a transparent plastic grid.

Since the larvae of S. dentinosa are gregarious until the 4th instar, a
more natural experiment (Test B) was made by using groups of neonate larvae on
potted plants, which were caged within transparent plastic tubes (20 cm.
diameter; 50 cm. height). Each potted plant represented one replicate and 10
first instar larvae were placed on each replicate. The species or varieties
of each plant tested, as well as the control plant, were replicated twice.

The larvae were left undisturbed except for the replacement of test plants
when necessary. The silk webs formed by colonies of larvae between successive
molts, were removed from the used test plants which had been replaced, and
were saved in 500 cc. paper cups. Later the width of the head capsules
contained in each silk web were measured, so the number of instars of 5.
dentinosa larvae which developed each of the various test plants was
determined. Both experiments were conducted in quarantine, under natural day
length and ambient temperature from April to May.

Complete larval development occurred only on the control plant (E.
seguierana). Minimal feeding was recorded on Helianthemum apeninum on 3
larvae in test A, and 4 larvae in test B molted to the 2nd instar. On the
other test plants no feeding was observed and the larvae died in 3-4 days

without molting (Table 1).

Ff
Table 1. Larval development of Simyra dentinosa on different plant species.

Testing made at the USDA Rome Laboratory in 197.

TEST A TEST B
No. Individuals Surviving To: No. Individuals Surviving To:
STAGE STAGE

DL sleet AV Vie Pups Adult I Il I IV VI Pup Adult

Euphorbia seguierana (Control) 10 TROCT 6 20m 2te 2Oe-20y 15015: el
Triticum aestivum 10 20
Secale cereale 10 20
Phalaris canariensis 10 20
Poa pratensis 10 20
Dactylis glomerata 10 20
Zea mays a “
Rheum rhabarbarum 10 2
‘Typha latifolia 10 2
Sedum alba 10 20
Helianthemm apeninm 10 Sy) 2 4
Fagopyrun tataricum 10 20
Asclepias syriaca 10 2

A. speciosa Torr. 10 20
Alyssum argenteum 10 2
Iris sibirica 10 20

Chamaesphecia sp. (Lepidoptera: Sesiidae)
(P. PECORA, and M. STAZI)

From infested roots of Euphorbia virgata “group”, collected at the end of
October 1986 near the Danube delta in Romania, only a few adults of C.
crassicornis emerged in July 1987. These adults laid only unfertile eggs, so
no host specificity tests were made. Another collection of infested roots,
containing various stages of larvae of C. crassicornis, was made in October
1987 in Romania. If adults emerge and we get fertile eggs, a larval survival
test will be conducted in 1988 on several closely related Kuphorbia spp. and

plants of economic importance.

Taxonomic investigations on the gall midge
Dasineura sp. near capsulae
(P. Pecora)

A European gall midge, whose larvae produce capsule-like galls on
Euphorbia spp., was selected in 1982 as a candidate for the biological control
of leafy spurge in North America. Host specificity tests, made at the USDA's
laboratories at Rome (Italy) and Albany (California) from 1983 to 1987, using
test insects from a population which occurs at S. Rossore (Central Italy) on
E. esula, demonstrated that this midge is able to develop only on plants in
the genus Euphorbia (subgenus Esula).

In the midge complex associated with Euphorbia spp. in Europe, four
species (Dasineura capsulae Kieffer, D. loewi (Mik), Perrissia corniflex
Kieffer, P. euphorbiarum Kieffer) which produce capsule-like galls have been
described (Kieffer 1901, Kieffer 1909, Houard 1908). Recently, Solinas and
Pecora (1984) Suggested, that in this complex, "only two good species
(D. capsulae and D. loewi) may remain". One of these "good species",

D. capsulae was recorded from E. cyparissias L., E. esula L., E. nicaeensis
Allioni, E. pithyusa L. (Kieffer 1901, Houard 1908), E. falcata L., E. lucida
Waldstein & Kitaibel (Buhr 1964) and the other, D. loewi, was found on

E. seguierana Necker (Buhr 1964).

Adults originating from larvae which produced capsule-like galls on
E. cyparissias and EH. esula, and which emerged in 1983, were identified as
Dasineura capsulae Kieffer by M. Solinas. Specimens of adult midges tested in
quarantine at Albany, California, in 1986, whose larvae came from E. esula

capsule-like galls collected at S. Rossore in mid-June 1985, were sent

10
by R.W. Pemberton, USDA/ARS Albany laboratory, to R.J. Gagné, USDA-ARS-SEL
(Systematic Entomology Taboreti cee) for identification. The specimens examined
by Gagné showed a shorter ovipositor than those illustrated by Solinas and
Pecora (1984). R.J. Gagné stated that "these specimens belong to neither D.
capsulae nor Bayeria capitigena, although they do belong to Dasineura in the
broad sense". Since the taxonomy of the midge complex associated with
Euphorbia spp. in Europe is not yet clear, R.J. Gagne suggested calling the
midge from E. esula "Dasineura sp. near capsulae" until it is properly
described and named. From the controversial results of the taxonomic
determinations it seems that two species have been taken from the E. esula and
E. cyparissias capsule-like galls, with one of the following scenarios:

er) That one of these species is an inquiline. Inquilines lay eggs in
galls already initiated by other species. Their larvae outcompete
and indirectly cause the death of the gallmaker;

(2) That many differently-shaped cyathium galls are formed on Euphorbia
Spp. Possibly, cyathium and leaf capsule galls occurring at
S. Rossore were produced by different species and were mixed during
the collection to provide material for host specificity testing.

(3) More than one species of gallmaker make the same kind of gall.
Possibly the species, collected in 1982/83, has now been replaced by
another species which now occupies the area.

In order to make an indepth study of the taxonomy of the complex of gall

midges on Euphorbia spp., R.J. Gagné travelled to Europe June 6 to 27, 1987.
The objectives of the trip were to study the types of gall midge species that

feed on Euphorbia spp.; to collect galls from which to rear new specimens, for

el
making neotypes for types that are lost; and to meet with European colleagues
to discuss various facets of this research. This trip was fruitful for
collecting different kinds of galls for museum work, and for consulting with

his European colleagues.

(a) Collection of biological material

R. J. Gagné collected cyathium and leafy capsule-like galls and rosette-like
galls both at S. Rossore (Italy) on E. esula and at Scharrachbergheim, 15 kms.

West of Strasbourg (France) on E. cyparissias.

(bd) Museum Work
Dr. Gagné visited the Entomologische Institut, Eidgenodssichen Techniche
Hochschule in Zurich, where the Bremi collection is deposited. Dr. H. Sauter,
curator of the insect collection at this Institute, allowed Gagné to borrow
certain types of the spurge midges. He also visited the College of St.
Augustin at Bitche, where Abbé J.J. Kieffer described hundreds of species of
gall midges, including several species from spurges. However, nothing

remained of the Kieffer collection.

On the way back to Rome, Dr. Gagné stopped in Florence at the Museo
Zoologico “La Specola", to see the collection of Rondani for the types of some
species in the genus Dasineura, to which the spurge midges presumably belong.
The types were not there; however, he found some additional types of spurge

midges collected by Bremi in Zurich.

12
Dr. Gagné, Professor Solinas and I met in Perugia, and explored the
possibility of the existence of two species of the capsule gall maker, one on
E. esula and one on E. ypariassias, and we arrived at the aforementioned
scenarios. Dr. Gagné stated that his major interest is to resolve the problem
of the types, in order to have available names for those spurge midges that
would be imported to North America as biological control agents of leafy

spurge.

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Aphthona abdominalis Duftschn.

L. Fornasari and M. Stazi

INTRODUCTION

This year additional testing was carried out to investigate, in different
ways,the host specificity of this flea beetle in the larval and adult stages,
and its ability to complete development on the six plants tested. Three tests
were made: an oogenesis test, a host suitability test, and a larval survival
test.
1. OOGENESIS TEST (LABORATORY)

MATERIALS AND METHODS

A no-choice test was conducted to assess the ability of A. abdominalis
overwintering adults to produce and lay eggs on six test plant species. In
addition to Euphorbia esula as control, the species screened were: E. supina,
E. maculata, E. tirucalli, EH. lathyris, E. marginata and Linum usitatissimun.
The adults used in this test were collected in the Rome laboratory garden on
September 9, 1986, and kept in outdoor cages with soil and wood chips as
shelter. Thewecharincnt started on April 2, 1987. The test plants were
presented as bouquets in cardboard cups (11 cm. diameter and 8 cm. high)
covered with a fine mesh nylon screen to allow aeration. Eight A. abdominalis
adults were put in each cup and 4 replications were made for each test plant.
Twice a week the bouquets were checked for oviposition and replaced with fresh
ones. As the adults died they were dissected to check for the presence and
condition of the eggs in the ovarioles. The experiment was conducted in a
laboratory room with natural light and the temperature ranging between 20 and

25°C. It ended when the last of the insects on the test plants died on

June 19, 1987.

14
RESULTS
Oviposition occured on the control (248 eggs) and on Euphorbia maculata
(12 eggs). Eggs were found on stems of the plants in the bouquet and on the
caps of the vials containing the bouquets. While the eggs laid on E. esula
hatched normally, the eggs laid on E. maculata did not hatch (temperature was
approximately 25°C R.H.=80-90%). No egg development was found during

dissection of the adults which had fed on the other test plant species,

2. HOST SUITABILITY TEST (LABORATORY)
MATERIALS AND METHODS

The objective of this test was to see if A. abdominalis could complete
development on the following test plants: E. maculata, E. Supina, E.
tirucalli, E. marginata. KE. esula was used as control. On August 6, 1987 ten
Ovipositing adults were placed on each potted plant, placed under transparent
plastic cylinders (60 om. high x 19 cm. dia.) with the top covered with
netting, and four screen covered holes (12 en. dia) on the sides to allow air
circulation. Four replications were made for each plant species tested and
the control. Fifteen days later (on August 21) these adults were recollected
and the tubes removed. On September 7 the plastic cages were replaced over

the plants, and checked daily for emergence of new adults.

RESULTS
From September 29 to October 9, 16 adults were found on the control. On

October 7, one adult was found on kK. marginata.

i)
3. LARVAL SURVIVAL TEST (LABORATORY)
MATERIALS AND METHODS

The objective of this trial, carried out in quarantine in June and July
1987, was to determine the ability of neonate larvae of A. abdominalis to
develop on these test plants, on which adult feeding activity had been
observed in the no-choice feeding tests made in the summer of 1984, 1986 and
1987. The following plant species were used: E. esula (from Italy) as
control, EH. marginata, HE. maculata, KE. supina, KH. lathyris, EH. tirucalli, E.
serpyllifolia, Ricinus communis and Linum usitatissimum. In previous testing
there was no feeding on L. usitatissimum, however, it was tested again because
of its economic importance.

Larvae used in this test came from eggs laid by adults collected in the
laboratory garden and caged in paper cups with E. esula bouquets as
oviposition plants. The eggs were kept in a temperature cabinet at a constant
temperature (25 e025 5C) on wet blotting paper in Petri dishes until eclosion
(about 8 days). Five neonate larvae were put on the root collar of the plants
at soil level and two weeks later transparent plastic tube cages (the same
kind used in the host suitability test) were placed over the plants. Five
replications were made of each test plant, thus 25 neonate larvae per test
plant species were used. Later, the number of adults emerging from each of
the plants was recorded.

RESULTS

A. abdominalis larvae completed their development only on the control, and
on E. lathyris. The larval development took about 30 days. From the control
7 adults (=28% survival) emerged in X 28.4 + 3.45 days. Seven adults (=28%

survival) also emerged from E. lathyris, taking about the same time x 28.4 +

3.64 days.

During the trial the temperature ranged from a minimum of 12°C to a
maximum of 35°C. The mean temperature range measured at 2-hour intervals was
17-30°C. The mean relative humidity was 54-75% with a minimum of 26% and a
maximum of 93%.

CONCLUDING REMARKS

This year testing was not extensive enough to define the host range of A.

abdominalis. Next year additional plants will be tested and an open field

test that we were unable to make in 1987 will be made.

Ly
Collection and Survey Trips
(P. PECORA, M. STAZI, M. CRISTOFARO, and A. LAREGINA)

Bayeria capitigena (Bremi) (Dipt.: Cecidomyiidae); (M. Stazi, M.
Cristofaro, collectors):

Five shipments of tip galls containing various larval instars and pupae of
B. capitigena were shipped to Albany, California. These galls were collected
on E. esula at S. Rossore, Italy on May 11 (140 galls), May 22 (320 galls),
May 29, (350 galls), June 3 (250 galls) and July 15 (220 galls). Twelve
working days were required to make these collections.

Dasineura capsulae Kieffer (Dipt.: Cecidomyiidae); (M. Stazi, M.
Cristofaro collectors):

About 8,000 mature larvae of D. capsulae were produced from 1100 galls
collected on E. esula at S. Rossore in mid-June 1987. These larvae were
transferred to 4500-ml. acrylic containers with a 3-4 cm. deep layer of moist
peat moss and fine sand mixture to hibernate until the following spring. Two
working days were spent to collect this stock of galls.

Oberea erythrocephala Schrank (Col: Cerambycidae); (M. Stazi, M.
Cristofaro collectors):

Adults of this longhorned beetle, collected on E. esula at S. Rossore on
June 3 (210 adults), June 15 (210 adults) and July 7 (97 adults), were shipped
to Albany, California for field releases. Six working days were needed to
collect these beetles.

Aphthona flava Guill. (Col.: Chrysomelidae); (M. Stazi, M. Cristofaro
collectors):

Four shipments of this flea beetle were sent to Albany, California for
field releases. These insects were collected on E. esula and E. cyparissias

on June 15 (1900 adults), June 22-30 (3100 adults), July 7 (700 adults) and

18
JULY el Ph GL5OC adults). Ten days were spent for these collections.

Aphthona cyparissiae (Koch) (Col.: Chrysomelidae); (P. Pecora, A. Laregina
collectors):

Two thousand eight hundred adults of A. cyparissiae were collected on E.
Cyparissiass near St. Polten (Austria) between June 19 and July 2, 1987. In
addition, 1000 adults of this flea beetle were collected on E. cyparissias and
200 on E. virgata in two localities near Gyor (Hungary) in the first week of
July. These insects were shipped to Albany, California for field release.
Eleven days were necessary for these collections.

Aphthona czZwalinae (Weise) (Col.: Chrysomelidae); (P. Pecora, A. Laregina
collectors):

Nine hundred adults were collected on E. esula in Eastern Austria on
July 1-2, 1987, and 100 adults were collected in Hungary (Gyor area) on E.
esula in the first week of July. Four days were spent collecting Aphthona
cyparissiae and A. czwalinae.

A trip was made to Romania and Czechoslovakia in mid-October by P. Pecora
and M. Cristofaro to collect Chamaesphecia crassicornis (Lep.: Sesiidae) and
Oxycesta geographica (Lep.: Noctuidae), and to locate new sites infested with
larvae of these species. One hundred fifty plants of E. virgata containing
larvae of C. crassicornis in various instars were collected in the Braila area
(Romania). Three hundred mature larvae of 0. geografica were collected on E,
virgata and E. stepposa in the same area. C. crassicornis larvae were also
found on E. virgata at Sturovo in Czechoslovakia. In this locality 22% of the

plants examined (n=120) were infested.

YELLOW STARTHISTLE PROJECT - 1987

Learornasari.

Eustenopus villosus (Boheman, 1836).
INTRODUCTION
The insect called Eustenopus abbreviatus Faust. and E. hirtus (Waltl) in
previous reports is in reality Eustenopus villosus (Boheman, 1836) (determined
by Dott. E. Colonnelli, Dipartimento di Biologia Animale e dell'Uomo, Viale
dell'Universita', 32 - Roma, Italy). This is the most recent and hopefully
final name, after a taxonomic revision of the genus that involved several

specialists in different countries.

In 1987 emphasis was placed on assessing the potential of EK. villosus as
biological control agent for yellow starthistle CYST) in=the-U.S< Testing was
confined to the host specificity of this weevil under no-choice (Test No. 1)
and choice (Test No. 2) conditions, on plant species present in the list
approved by the Technical Advisory Group on Biological Weed Control. In
another study (Test No. 3) the ability of E. villosus larvae to develop in
buds of various plant species was investigated. Adults collected in the field
on Centaurea solstitialis in Greece were used for these studies. When they
arrived at the Rome laboratory they were allowed to feed for at least 48 hours
on YST buds (obtained from Greek plants) before copulating pairs, i.e. a male

and a female, were selected for tests.

TEST 1 - ADULT FEEDING AND OVIPOSITION NO-CHOICE TEST.

METHODS

This test was conducted in a quarantine greenhouse (temp. = 22.5 + 4.07
C, range = 14 - 33°C; R.H. = 60.7 + 17.76%, range = 28 - 88%, and natural
lighting) on 21 plant species, listed in Table 1. Branches of each test plant
were caged in black, nylon tulle sleeve cages (a system previously used in
1985 and 1986). Two couples of E, villosus were caged on each potted plant and
there were 5 replicates of each test plant species. Weevils were permitted to
feed and oviposit for 7-10 days, then moved onto another fresh caged plant and
left for 7-10 days. This procedure was repeated until all the beetles died.
All the exposed buds were dissected to estimate and record the feeding damage
and count the number of eggs laid. In addition, dead adults were dissected to
determine sex, and to observe the condition of ovaries and the number of eggs
retained and not laid. This test started July 6 and finished August 27.

RESULTS

The results of this test are reported on Table 2 and the pattern of host
preference is illustrated in Fig. l.

Fig. 2 shows the total number of exposed and damaged or fed-on buds for
each species. The highest numbers of damaged buds, after the control, were
observed on Centaurea maculosa, C. paniculata, C. alba, C. scabiosa, C. cyanus
and C. calcitrapa. If we consider (Fig. 2) the percentage of damaged buds,
Safflower had the highest value (58.3%) after the control (87.8%), followed by
Centaurea paniculata (57.3%), C. scabiosa (51.0%), C. alba (49.1%), Cc. cyanus

(41.7%) and C. jacea (39.4%). On Gazania splendens 38.1% of the exposed buds

were fed on. A small percentage of buds Zinnia elegans (14.8%) and Achillea
millefolium (0.9%) were fed on. In spite of the feeding on Carthamus
tinctorius, no eggs were laid on this species under no-choice conditions,
confirming data from previous tests on safflower by Clement and Mimmocchi
(1986 Annual Report). They observed no development of the ovaries in EK,
villosus females fed on safflower under no-choice conditions and no
Oviposition. The 1986 tests also showed that under choice conditions "only
minor feeding was recorded on safflower (only on the leaves) when YST buds
were present".

Eighteen eggs were found (Fig. 4) on C. scabiosa, 8 on C. maculosa, 5 on
C. napifolia, 4 on C. jacea, and 107 on the control. The damage of
E. villosus was negligible to plants of economic (agricultural or ornamental)
importance tested, i.e. safflower, Gazania splendens and Zinnia elegans
(Wigs )e? The longevity of E. villosus was recorded and is shown in Fig. 5

In comparison to the control (x 21.8 + 8.54 days), its longevity was
considerable on Centaurea maculosa (x tee et 12.70 days), Carthamus tinctorius
(x 14.6 + 4.52 days) and Centaurea scabiosa (x 13.3 + 6.54 days). Examination
of the ovaries of efetingae tte in the test showed that well developed ovaries
were present only in the females which fed on the YST control. There was no
feeding or oviposition on Centaurea americana, but buds and flowers of this
species were infested with flies, whose larvae were found feeding in the
capitula. Because of this artifact, this test will be repeated next year

using insect-free plants.

TEST 2 - ADULT FEEDING AND OVIPOSITION CHOICE TEST.
METHODS
This test, started July 6 and finished August 12, was carried out ina
quarantine greenhouse (temp. = 22.2 + 3.950, range = s149-9556Cs sh eee Ores
17.62%, range = 31-88%, and natural lighting) using Cynara scolymus, Zinnia
elegans, Calendula officinalis, Centaurea americana as test plants, and
Centaurea solstitialis (Greece) as the control. A choice was given between
the YST control and each of the four test plant species. Each treatment was
replicated five times. Branches of YST and test plants were tied together and
caged inside black, nylon tulle sleeve cages. Two couples of E. villosus were
introduced into each cage. The test was terminated when a choice was no
longer available i.e., when YST branches were completely destroyed by the
beetles. All exposed buds were dissected to record feeding damage and number
of eggs laid.
RESULTS
The results of this test are reported on Table 3. Nibbling occurred on

three buds of Zinnia elegans and no feeding was recorded on the other test
plants. The yellow starthistle control plants were heavily damaged with
complete bud destruction, and eggs were laid only on the control. On Centaurea
americana neither feeding nor oviposition were observed, but this species will
be tested in 1988 again, because the buds were infested with larvae of

indigenous flies.

23
TEST 3 - FIRST INSTAR LARVAL SURVIVAL TEST.
METHODS

This test was made between July 23 and August 24 in a quarantine
greenhouse (temp. = 22.7 aoa oo erage 2eL5 852-05; RH. = Gl eel BO,
range = 28 - 87%, and natural lighting). These eggs were placed in 35 ml.
plastic cups provided with a layer of moistened (not wet) plaster of Paris on
the bottom.

The following plant species were used: Centaurea solstitialis (from
Greece) as control, and the test plants Carthamus tinctorius, Cynara scolymus,
Zinnia elegans, Calendula officinalis, Centaurea americana, C. cyanus, C.
scabiosa, C. napifolia, C. gacea and C. maculosa.

Neonate larvae from eggs kept in a temperature cabinet at the constant
temperature of 25°C were transferred with a fine brush into holes made in the
buds of the test plants with a scalpel (30 buds/plant species). The holes
were then covered with plant bud tissue. After about 25 days, or when the
plant condition required it, these buds were dissected.

RESULTS AND DISCUSSION

This test was conducted to try to overcome the difficulties encountered in
a similar study in 1986 (Clement and Mimmocchi, 1986 Annual Report). Last
year a test carried out placing fertile eggs into the test plants buds was not
successful, because when the eggs hatched the larvae were confronted with
altered plant tissue in the hole made to insert the egg into the bud. This
kind of tissue is not encountered in a normal oviposition hole. Problems
arose this year too, probably due to the fragility of first instar larvae,
even though maximum care was taken in handling them. Very few larvae
developed and reached the pupal stage on the control, thus the results

obtained on test plants were not appraisable. More work is needed on

technique.

24
CONCLUDING REMARKS
E. villosus studies confirmed that this weevil is a potential control

agent of yellow starthistle. In spite of the rather broad feeding spectrum
under no-choice conditions, normal oogenesis and oviposition occurred only on
the control, and scarcely on Centaurea scabiosa, C. maculosa, C. napifolia and
C. jacea under no-choice conditions. Appreciable feeding occurred only on the
plants of the genus Centaurea. Neither oogenesis, nor oviposition were
observed on safflower. Host specificity testing and studies on E. villosus

are expected to be completed in 1988.

Collection and Survey Trips.

In mid-June a trip was taken to Sicily to look for Larinus curtus in the
Palermo area, and to collect specimens of this weevil to be identified and
reared at the Rome laboratory for future testing. Several localities were
surveyed and about 300 adults were collected on Centaurea solstitialis subsp.
showii.

At the end of June a trip was taken to Greece to collect Eustenopus
villosus and to review the work going on with Larinus curtus and L. minutus
(the last one is presently under study by C.1.B.C.). Six hundred and sixty E.
villosus adults were collected in Doirani, to provide material for the 1987
Rome laboratory experiments. L. curtus was found in several sites and was
particularly abundant in Oreokastro, near Thessaloniki, where three people
collected 150 adults in about one hour. In that particular site YST is being
crowded out by grassy plants, thus endangering the L. curtus population. For
this reason, Dr. Sobhian is trying to develop a system for rearing large

numbers of this weevil at our laboratory in Greece.

MEETINGS ATTENDED
‘ International Symposium on Fruit Flies of Economic Importance (Workshop on

Research - Coordination CEC - IOBC). Rome, Italy, April 7-10, 1987.

ea OL Owd! .

List of plant species used in the no-choice adult feeding, oviposition and

longevity test with E. villosus.

10%.
aes
Ba
al
14,
13
LO.
17.
18.
19.
20.

aie

Centaurea solstitialis L. (Greece)
Silene vulgaris (Moench) Garcke
Antirrhinum majus L.

Zinnia elegans Jacq.

Aster principessa

Calendula officinalis L.

Achillea millefolium L.

Targetes erecta L.

Gazania splendens E.G. & A. Henderson
Carduus pycnocephalus L.
Cynara scolymus L.
Carthamus tinctorius L.
Centuarea scabiosa L.
Centuarea paniculata L.
Centaurea maculosa Lam.
Centaurea calcitrapa L.
Centaurea napifolia L.
Centaurea alba L.
Centaurea jacea L.
Centaurea cyanus L.

Centaurea americana Nutt.

Table 2. E. villosus 1987 adult feeding, oviposition and longevity no-choice test

Total Total Feeding* Total Total Longevity Bud
Plant Species No. eggs No. feeding Damage No. of No. of (days) diameter
laid punctures rating exposed damaged X+SD Range (m)
X + SD buds buds
fear siiredianisti tials peeeeiO7Eay sa 440 wae 2.250.452 OT LBS Tem
Silene vulgaris 0 0) 0 63 O fh ANG, EPiyis
Antirrhimm majus 0 0 0 46 0 Tees gums 1 2
Zimia elegans O 4 0.57+0.524 27 4 ednimem oem Os Le
Aster principessa O O 0 43 0 Te E70 TS)
Calendula officinalis e) QO O oo 0 iV cae Zoey
Achillea mllefolium 0 38) 0.86+0.378 ca. 2,000 19 8.3 + 2.83 PANE
(27 corymbs) (corymb 20:50
Targetes erecta O O O 28 O (hess) 9:12
Gazania splendens O 12 0.60+0.548 on 8 (ee ®) 14:17
Carduus pycnocephalus O 16 0.80+0.447 43 10 i ete 4: 6
Cynara scolymus O 0) 0 2, 0 (fe) 60:80
Carthamis tinctorius 0 32 1 % 21 14.6 + 4.52 10:14
Centuarea scabiosa 18 69 1.67+0.500 B 50 13.3 + 6.54 10:13
Centuarea paniculata 0 110 2 164 UW 12.1 a4. by
Centaurea maculosa 8 177 2 437 166 LT] 2 tle. 10 ig
Centaurea calcitrapa 0 54 2 138 49 Se] tepsiee BOs
Centaurea napifolia 5 aE 2 ng 50 10.8 + 4.35 5:08
Centaurea alba 0 69 2 116 57 H.8+5.68 8:12
Centaurea jacea 3 46 1.6240.517 99 3992+ 4.08 9:1
Centaurea cyanus 0 64 2 120 50 8.1+ 2.63 4:06
Centaurea americana 0 0 O 18 0 [is stital) 16:20

*Based on a scale of 0 to 3: O = no feeding; 1 = very little feeding, no effect on bud development; 2 = very
little feeding on a well developed capitula, but considerable damage to young buds; 3 = heavy damage, complete

bud destruction.

Table 3. E, villosus 1967 adult feeding and oviposition choice test

Total Total Feeding Total Total
Plant Species No. eggs No. feeding Damage No. of No. of
laid punctures rating 3/ exposed damaged

buds buds

ys 7.p.2/ YST yr Tp. Yoeel res YSDRMMGEPs

Cynara scolyms 6 O 35 O 47 5 27 O
Zinnia elegans 16 e) ep) 0.20+0.447 149 et ~D y)
Calendula officinalis 10 O 193 O 1 8644 92 O
Centaurea americana 14 O 49 O TO 26 44 O

ey, YST = Yellow starthistle

2/ TP = Test plant

3/ Based on a scale of O to 3: O = no feeding; 1 = very little feeding, no effect on bud development;

2 = very little feeding on a well developed capitula, but considerable damage to young buds; 3 = heavy

damage, complete bud destruction.

|
|
|

|
| |
vi

Bige «Js.

YST (CONTROL)

Cc. paniculata

Cc. scabiosa

Cc. alba

{a
IPS "

° cyanus

c. calcitrapa

Cc. napifolia

| Centaurea maculosa

Carthamus tinctorius

Achillea millefolium

Carduus pycnocephalus

Gazania splendens

Zinnia elegans

Silene vulgaris

Antirrhinum majus

Aster principessa
Calendula officinalis
Tagetes erecta

Cynara scolymus

Centaurea americana

Feeding damage in the no-choice test.

100 150 200 250

NO. OF FEEDING PUNCTURES

300

350

400

450

Fig. 2. Number and percentage of damaged buds in the no-choice test.

‘YST (CONTROL)

Centaurea maculosa

Cc. paniculata

Cc. alba

Cc. cCyanus

C. scabiosa

Cc. calcitrapa
C. jacea

Cc. napifolia
Carthamus tinc.

Achillea millet.

Carduus pycnoceph.

Gazania splendens

‘

Zinnia elegans

Silene vulgaris

Antirrhinum majus

Aster principessa

Calendula officin.

Tagetes erecta

Cynara scolymus

Centaurea americanaf]

CLP IL OEE LILES BOLE CLI ID ECE IELTS SAI IROL IMIG LL TILT EG)
et Cie
SLLL ELLA PLL ASSP AALS ff fl fea sf fea (38.0) 437

VLE RIAD Le TAI SLD A th IT ap BATA FATT Fe

CLL Le NAO

GILT IAS LEIS, (41957)

LLANE 61)

ee ee Le SS)

ALLEL LA (39.4)

Ame Se)

eAecd (58.3)

okerded (0,9) ca. 2000
HJ (23.2) 3
os
ed (38.1)
Peren ]
(14.8)
eRe eee a]
CJ Exposed buds
Sy
ciicd Buds with feeding damage
———————— ( ) % Exposed buds with feeding
damage
sean rere
ne)
a
0 50 100 150 200 250 300

NO’ OFT BUDS

YST (CONTROL)
Centaurea maculosa
C. paniculata

C. alba

Cc. cyanus

Cc. calcitrapa

C. napifolia

C. scabiosa

C. Jacea
Carthamus tinctorius

Achillea millefolium

Carduus Ppycnocephalus
Gazania splendens

Zinnia elegans

Silene vulgaris
Antirrhinum majus
Aster principessa
Calendula officinalis
Tagetes erecta

Cynara scolymus

Centaurea americana

* Based on a scale of 0 to 3:

cee

Feeding damage rating in the no-choice test.

(o>)

Re,

1 eee

FEEDING DAMAGE RATING*

ind 3

O= no feeding, no effect on bud development;
2= very little feeding on a well developed capitula,

but considerable da-

mage to young buds; 3= heavy damage, complete bud destruction.

1 We Ry Ox A

YST (CONTROI.)
Centaurea scabiosa
Cc. maculosa

C. napifolia

Cc. jacea

Cc. paniculata

Cc. alba
Cc. cyanus

Cc. calcitrapa

Cc. americana
Carthamus tinctorius

Achillea millefolium

Carduus pycnocephalus
Gazania splendens
Zinnia elegans

Silene vulgaris
Antirrhinum majus
Aster principessa
Calendula officinalis
Tagetes erecta

Cynara scolymus

NO.

50) 605570

EGGS LAID

80 90

100

110

Number of eggs laid on the test plants in the no-choice test.

Fig. 5. Adult longevity in the no-choice test.

YST (CONTROL)

Centaurea maculosa

Carthamus tinctorius

Centaurea scabiosa

C. paniculata
C. alba
C. napifolia
Cc. jacea

Cc. calcitrapa

Achillea millefolium
Centaurea cyanus
Zinnia elegans
Silene vulgaris

Antirrhinum majus

Aster principessa

Calendula officinalis

Tagetes erecta
Gazania splendens
Carduus pycnocephalus

Cynara scolymus

Centaurea americana

3) 10

MEAN ADULT LONGEVITY (DAYS)

a) To ee Oe

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Mer Pas 04!) 32 Pou

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Ma OO Bet

dh Sere

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a ota aaa a edge a

DIFFUSE KNAPWEED PROJECT 1987

Paul H. Dunn and G. Campobasso

Bangasternus fausti Reitter (Coleoptera: Curculionidae)
INTRODUCTION

For the fourth consecutive year we continued screening the seed-feeding
weevil Bangasternus fausti (Col.: Curculionidae). Research objectives for the
1987 research season were: (1) to collect live adults of B. fausti in Greece
to conduct tests at Rome, Italy, (2) to conduct oviposition, rae survival
and development tests in the laboratory, (3) to continue study of the biology
of the main species of diffuse knapweed in Greece.

Progress made under each objective is summarized below.

OBJECTIVE 1

MATERIALS AND METHODS

Living adults of B. fausti needed for conducting host specificity and
biological studies were collected in northern Greece between May 18 and
June 2. Emerging adults that had not started oviposition on the host
Centaurea diffusa were hand-collected and brought back to the Thessaloniki
laboratory where they were separated according to sex. Before sending the
adults to Rome, dead and injured weevils found in the collection were
discarded.

RESULTS
A total of 1,270 adults of B. fausti were packed and shipped to the Rome

laboratory. Only N=30 (2%) of weevils were found dead or injured.

OBJECTIVE 2
EXPERIMENTS

1. Oviposition on single plant

2. Multiple choice test

3. Larval survival test

MATERIALS AND METHODS

Test plants: Plant spp. used for these laboratory trials were taken from the
master list compiled in 1985-86. This year seventeen plant spp. in the genera
Centaurea, Carduus, Carlina, Arctiun, Silene, Calendula, Zinnia, Ranunculus,

Malva, Tagetes, Tanacetum, Anthiorhynum, and Cirsium were tested with B.

Tes oie

OVIPOSITION ON SINGLE PLANTS

MATERIALS AND METHODS

Prior to setting up the experiment at Rome, adults of B. fausti shipped
from the Thessaloniki laboratory were fed on plants of diffuse knapweed for
about 4 days to allow them to recover from possible travel stress. On June oH
these adults were placed on potted plants covered with transparent plastic
cylinder cages (20 cm. diam., height 70 cm.) with four holes (10 cm. dia.) in
the walls covered with nylon organdy and an organdy top kept in place with a
rubber band. On each potted plant 2 male and 2 female weevils were used. One
potted plant comprised 1 replicate. Test plants were inspected every three
days and adult feeding damage was quantified and recorded. The trial was set
up on a quarantine greenhouse with fluctuating temperature and humidity (min.
15°- max.31°C; Rh min. 30% - max. 75%) with a photoperiod of ca. 16 hours.
The test lasted until all adults died. Eggs found on test plants were counted

and

36
recorded and left undisturbed to ascertain if hatching larvae were able to
complete their life cycle on the test plant. A summary of the number of
replications, average egg production, average of seedheads infested is shown
in table l.

RESULTS

Table 1 provides details and results of the no-choice oviposition tests.
Oviposition occured only on plants in the genus Centaurea. The most infested
plant was control x 158 055.6 eggs/rep, followed by C. pseudoalba x aos oat
35.3 eggs/rep, C. alba x 21.5 + 27.8 eggs/rep, and C. cineraria x 3.3 et. 5
eggs/rep. Besides the controls, no larval development occurred on the other
Centaurea spp. even though flowerheads of these plants were superficially
Similar, morphologically, to those of the control. In our judgment, the most
probable causes of larval development failure were: (1) presence of feeding
deterrents, (2) hard tissue structure of seedhead involucral bracts, (3)
seedhead growth (of non-host plants) not synchronized with occurrence of first
instar larvae. Adult feeding damage was observed on Centaurea diffusa and
sometimes on C. alba and C. pseudoalba but not on the ornamental plant spp.

included in the test.

MULTIPLE CHOICE TEST

The object of this test was to determine if, in a cage situation, adults
of B. fausti would select any of the exposed test plants as hosts. The test
was conducted in a quarantine greenhouse with fluctuating temperature and
humidity (min. 15°C-max. 31°C, Rh min. 30%-max. 75%) with a photoperiod of ca.

16 hours. On June 5, six males and six females of B. fausti adults were caged

Di,
in pots each containing 3 test plants and a control plant, (C. diffusa - Greek
origin). Each pot was covered with a transparent plastic cylinder cage which
differed only in size (33 cm. diam.; 80 cm. height) from those used in the
previous experiment. There were 4 different combinations of test and control
plants (treatments) and each treatment was replicated 6 times except for
Centaurea panicula and Carduus thoermeri that were replicated 4 times. Plants
and insects were randomly combined and each pot served as a replicate.

RESULTS

The data obtained in the multiple choice test are summarized in table 4.
The failure of the insects to oviposit on any plants except the control and
Centaurea pseudoalba despite the different plant combinations offered in this
test, have confirmed B. fausti's high degree of specificity. Adult feeding
occurred mainly on controls, but occasionally the adults were observed to feed
on C. alba, C. cineraria, and C. napifolia, none of which are considered
plants of particular economic value. C. cineraria is, however, a common
ornamental.
FIRST INSTAR LARVAL SURVIVAL TEST

The following plant spp. were used for the lst instar larval survival
test: Centaurea diffusa (control), C. alba, C. pseudoalba, Cc. napifolia, C.
cineraria, C. paniculata, Cirsium lanceolatun, C, eriophorum, Carduus
thoermeri, Calendula officinalis, Zinna elegans, Tagetes erecta, Ranunculus
auricomus, Anthirrhynum majus, Malva silvestris, Tanacetum vulgare, Carlina
corimbosa, Arctium lappa, Silene vulgaris. Two buds each of the 5 test plant
replicates were infested with two fertile B. fausti eggs, (total of 20
eggs/test plant). The experiment was conducted in a quarantine greenhouse
with fluctuating temperature and humidity (min. 15°C-max. 5a C0. Rie dine

30%-max. 75%) with a photoperiod of ca. 16 hours. A fine camel brush was WSS

38
for inserting the fertile B. fausti eggs between the bracts of the buds on the
test plants, and all the infested buds were labelled. The experiment started
on June 10 and ended August 4.

RESULTS

Survival was seen in only one replicate. The validity of this experiment
was compromised by two polyphagous insects (Lepidoptera, Diptera), which had
oviposited into flower buds of test plants before the tested started, (test
plants had been kept outdoors for 15 days before use), ruining the seed head
content. Immature stages of both these unwanted insects were found while
dissecting test plants. Both insects are known pests of several plant
genera. The test will be repeated in 1988.

OBJECTIVE 3

Once we terminated B. fausti adult collection, three days were spent
surveying in northern Greece to locate new populations of different knapweeds
infested with B. fausti, Pterolonche inspersa, and Sphenoptera jugoslavica.

MATERIALS AND METHODS

On the road from Thessaloniki to Kavala several diffuse knapweed
infestations were seen. At each site, a random sample (n=50-100) of diffuse
knapweed plants were inspected, and dissected. The infestation rate of B.
fausti, P. inspersa, and S. jugoslavica was recorded as well as the plant
density/square meter at each site.

RESULTS

A total of five sites were investigated:

Site 1: South of Asprovolta, plant density 5-6 plants/sq. m. P. inspersa
larvae infestation 37%. S. jugoslavica larvae and pupae infestation 24%.

B. fausti adult infestation 19%.

Site 2: North of Asprovalta, plant density 10-12 plants/sq.n.

P. inspersa larvae infestation 3-42, S. jugoslavica not present, and B. fausti
adult infestation 42%.

Site 3: Southwest of Iraklitza, plant density 6-7 plants/sq.n.

P. inspersa and S. jugoslavica were not present. B. fausti adult infestation
2 he

Site 4: Elevtheropolis, plant density 1-2 plants/sq.n. P. inspersa
larvae, and B. fausti adults were not present. S. jugoslavica larvae and
pupae occurred in low percentage 2%.

Site 5: East of Kavala, plant density 10-15 plants/sq.m. P. inspersa
larvae infestation 40%, S. jugoslavica not present, and B. fausti adult
infestation 30%.

Figure 1 shows the collection sites discovered in Greece sofar.

OBJECTIVE 4

Examination of related thistles in the field still indicate that B. fausti
has a narrow host-spectrum and is confined to plants in the genus Centaurea.
At each visited site a random sample of 25-70 plants of Centaurea, Carduus,
Cirsium, Notobosis, Tyrimnus, Cnicus, Sylibum, and Onopordum were examined and

insects found were recorded. Results are presented in table 3A Bee.

40
CONCLUSIONS
The following positive points provide justification for considering the
seed weevil B. fausti as a safe and effective biological control agent for
diffuse and spotted knapweed:

1. Literature search and personal contacts with European curculionid
specialists did not provide any record of the weevil damaging plants
of economic value.

2. Laboratory studies are continuing to produce satisfactory results.
Weevil host spectrum is restricted to the genus Centaurea.

3. 3B. fausti is widely distributed in central and northern Greece, thus
massive collections can be made without too much effort.

4. Endangered American plants in the genus Cirsium were not accepted as
food by adults or larvae of B. fausti, nor were they accepted as an
oviposition substrate.

5. A single larva of this weevil is able to destroy 100% of seeds in one

seedhead.

Table 1. Summary of oviposition no-choice test of Bangasternus fausti, 1987.

TEST PLANTS

Centaurea diffusa (Control)
Centaurea pseudoalba
Centaurea alba

Centaurea cineraria
Centaurea napifolia
Centaurea paniculata
Cirsium lanceolatum
Cirsium eriophorum

Carduus thoermeri

Calendula officinalis

Zinnia elegans
Tagetes erecta
Ranunculus auricomus
Antirrhynum majus
Malva silvestris
Tanacetum vulgare

Carlina corimbosa

Arctium lappa
Silene vulgaris

TOTAL NO. OF
REPLICATES

DAN AKHA HAAN AHAN VD FN QW FS DW AO AW DW DO

TOTAL NO. OF NO. SEED HEADS NO. SEED HEADS

INSECTS IN EXPOSED/ REP INFESTED/ REP

REPLICATES Fee) (SD) X + (sD)

9 Of
12 12 239-5 | 0712.5) a0 115.6 (42.3)
12 12 15.0 (9.9) D702 5 (12.0)
12 12 WG) (4.6) 6.6 (3.7)
12 12 155 (2.3) 1.8 (2.6)
12 12 13.0 (5.2) 0.0 (0.0)
8 8 Ie plaz (37.5) 0.0 (0.0)
12 12 Bos (1.6) 0.0 (0.0)
2 12 2.0 (re 2)) 0.0 (0.0)
8 8 6.7 (3.0) 0.0 (0.0)
12 12 3.8 (2.7) 0.0 (0.0)
12 12 2.8 (0.4) 0.0 (0.0)
12 12 ey (2.4) 0.0 (0.0)
12 12 TO (2.4) 0.0 (0.0)
12 12 Dice (aS) 0.0 (0.0)
12 12 7.8 @es) 0.0 (0.0)
12 12 451 (20k) 0.0 (0.0)
12 12 Siaill CO%r7) 0.0 (0.0)
12 12 2a (@5,0)) 0.0 (0.0)
12 12 4.6 GO) 0.0 (0.0)

NO. EGGS
OVIPOSITED/REP
x (sD)
158.8 (53.6)
2505. (55D)
2125 parbeT.3)
3.3 (4.5)
0.0 (0.0)
0.0 (0.0)
0.0 (0.0)
0.0 (0.0)
0.0 (0.0)
0.0 (0.0)
0.0 (0.0)
0.0 (0.0)
0.0 (0.0)
0.0 (0.0)
0.0 (0.0)
0.0 (0.0)
0.0 (0.0)
0.0 (0.0)
0.0 (0.0)

SURVIVAL TIME OF

OF ADULTS IN DAYS

ous da ie)

Oy Be REO eat eee te eT ee

34.6
29.3
23.2
2lsl
13.5
Sale
10.5
ibg(s
11.2
Nae;
12.0
10.6
12.5
11.6
11.8
13.0
10.5
16.6
12.1

esl

(8.3)
(4.9
Gie4
(252)
C767}
(2.0
(2.49
(2.2)
(202
(2,0
(2.4)

(2.3)

(2.5)

Table 2. Summary of miltiple choice test of Bangasternus fausti, 1987.

TOTAL NO. OF # TOTAL NO. OF NO. SHED HEADS ~~ NO. SEED HEADS NO. EGGS

TEST PLANTS REPLICATES INSECTS IN EXPOSED/REP INFESTED/REP OVIPOSITED/REP
REPLICATES eae) x Seip) XK + (SD)

Centaurea diffusa (Control) ) 248.3 (111.8) 28.6 (9.7) 285.6 (%.3) )
Centaurea pseudoalba ) 1033 (2.5) 5.0 N52) bn Grea jay
Zinnia elegans ) 3 18 2.6 (0.5) 0.0 (0.0) 00> (0.09
Calendula officinalis ) 8.6 (1.5) O:0m (0.0) 0.02 (0.0 8)
Centaurea diffusa (Control) ) 331.0 (103.5) 187.0 (125.6) 265.6 (227.2) )
Centaurea alba ) 15.0 (4.0) 0.0 ©.0) O.0hs 020) 3
Arctium lappa ) 3 18 5.0 (0.4) 0.0 (0.0) 0:0 Oro)
Malva silvestris ) 6.0 (2.0) 0:05) (0.0) 0.0%) (O.0)83
Centaurea diffusa (Control) ) 483.6 (On) 31S 0N(168.5) 45250) (259.19) "
Centaurea cineraria ) 17,0 (7.9) O20 OO} 0.0 (0,0).
Cirsium lanceolatm ) 5} 18 2.6 (led) 00% (0.0) O07 5 5(0-0)8)
Carlina corimbosa ) 2.6 Geey) O02 210.0) ener a(syayl
Centaurea diffusa (Control) ) Dol.O (149.9) lol 6. (60s) mele. oom eee
Centaurea napifolia 14.6 (5.8) OF0.§ — (0.0) 0.0. (ory)
Silene vulgaris ) 3 18 4.6 (0.5) 0.0 70:0) 0.0 (0.G)e)
Antirrhymm majus ) 114.6 (35.7) OF (070) 0.0) (Oa
Centaurea diffusa (Control) ) Zoe (O.1) 237.0 (76.6)" s352.58) 27 crs
Cirsium eriphorum ) 3 18 13 (0.5) OrOme (020) 0.0 (010)®)
Tagetes erecta 1.6 (0.5) 0.07 10.0) 0.0; 8 (0,0) 9

@eeeoeoe e@eeeoeeeoeed e@eeeeeeeoeeooeeeoeeeeeeeee @eeeeoseeeeeeeeeeoeoeoeeeeeee @CCeeeSeeSeeeeseeeeeseeeeeeeeeeeeoeeee @eeeeoeeoeoooeeeod

Table 3A. Plant species associated with Diffuse Knapweed which were examined for
presence of Bangasternus fausti in Greece, June 1%.

LOCALITY

Asprovolta

PLANT SPECIES

Centaurea diffusa (Control)

. maculosa
salonitana
macedonica
rupestris
calcitrapa
4 solstitialis
iy altel
Jacea
cyanus
Carduus thoermeri
acanthoides
pycnocephalus
Cirsium eriophorum

‘ lanceolatun

; candelabrum

arvense

Notobasis syriaca
Tyrimms leucographus
Cnicus benedictus
Sylibm mariamm
Onopordum acanthium

illyricun

NO. PLANTS

EXAMINED INFESTED BY
B. fausti

65
49
36
23
23
41
23
41
37
45
67
39
54
32
40
32
40
32
ath
5
45
57

PLANTS

(27) 42%
(15) 31%
O

fe)

NO. ADULTS PRESENT

B. fausti

Table 5B. Plant species associated with Diffuse Knapweed which were examined for

LOCALITY

Iraklitsaa

PLANT SPECIES

Centaurea diffusa (Control)

maculosa
calci trapa
Carduus mutans

a pycnocephalus

e candicans

Cirsium arvense
Carthamus lanatus
Galactites tomentosa
Scolymis hispanicus

‘ maculatus
Onopordum illyricum
Carlina corymbosa

= acaulis
Syliibm mariamm
Echinops sphoerocephalus

is microcephalus
Cichorium intybus
Lactuca virosa

Cynara cardunculus

NO. PLANTS

De,
47

45
ue,

presence of Bangasternus fausti in Greece, June 197.

% PLANTS

(29) 59%
(19) 51%
O

NO, INSECTS PRESENT

3B. fausti

32
24

Table 3C. Plant species associated with Diffuse Knapweed which were examined for

presence of Bangasternus fausti in Greece, June 1987.

LOCALITY PLANT SPHCIES NO. PLANIS % PLANTS NO. INSECTS PRESENT
EXAMINED INFESTED B, fausti
ee Cane eae O82 en Ee ees
Palio’ Centaurea diffusa (Control) 47 (14) 30% 22
: alba 33 0 0
¥ salonitana 21 0 O
s rupestris 15 0 0
Carduus thoermeri 2g fe) @)
# pycnocephalus oi 0 0
Cirsium lanceolatum “4 6) O
; arvense 56 0 0
. eriophorum 21 O 0
Carthams lanatus 31 0 0
, dentatus 22 0 0
Scolyms maculatus 40 O 0
Onopordum acanthium 17 ) 0
a illyricum 19 0 O
Carlina corymbosa 32 O O
as acaulis 16 0 )
Sylitbun marian 33 0 0
Cichorium intybus 2 0 0

Cynara cardunculus 47 0 re)

Aceria centaureae Nal. (Acarina: Erophyidae)

Petition to Import the Eriophid Mite Aceria centaureae Nal.,
(a natural enemy of diffuse and spotted knapweeds)

into Quarantine in the United States for In-depth Testing.

Prepared by
Paul H. Dunn, Research Leader
Biological Control of Weeds Laboratory, USDA-ARS,

Rome, Italy.

INTRODUCTION

Aceria centaureae Nal. is a central European species of eriophyid mite
which causes severe leaf palin and sometimes death of rosettes of Centaurea
diffusa and some other Centaurea spp. In 1984 a colony of this mite was found
at Geroplatanos (Arnea), Greece by one of our staff scientists (Sobhian).

Preliminary out-of-doors trials showed that this mite would accept U.S.
biotypes of Centaurea diffusa as a host plant, and that it could be moved and
re-colonized in Thermi, where Dr. Sobhian's research facilities are located.
As a follow-up of the favorable results from these trials, a literature search
was made in 1986.

LITERATURE SURVEY
Reports of this mite are not common in the literature. There is no

information available on the biology but the information is adequate to

indteaterits distribution and host preferences.

Schroeder (1977), quoting Buhr 1964 mentions the pan-European distribution
of Aceria centaureae and gives Buhr'’s host records as Centaurea maculosa,

C. diffusa, C. micanthros and C. sadleriana. Schroeder (1977) also notes that
in surveys made by Commonwealth Institute of Biological Control (CIBC)
workers, the mite was found on C. maculosa in the Swiss Valais and on

C. diffusa near Lake Skutari in southern Yugoslavia. The mite has also been
reported in Italy by Nalepa (1898) and by Trotter and Cecconi (1903 ca.) on
Centaurea nigrescens and Centaurea scabiosa in the province of Treviso, in
Northern Italy. However, some of the host plants mentioned in the older
references are based on the presence of typical galls rather than on
examination of the mite. While they are probably correct, there remains some
question about the actual species of eriophyid concerned.

Henrik (1966) noted that the mite is a Central European species and that
slg cove be found throughout Hungary on Centaurea amara, C. maculosa,

C. scabiosa, C. sadleriana and C. pannonica. Houard (1908) adds Centaurea
(Staehelina) fructosa, C. alba, C. jacea, C. nigrescens, C. cineraria,

C. (Psephellus) delabata, C. rehenana, C. solstitialis, C. calcitrapa, and
C. aspera, C. aspera var. brevisetosus to the list of host plants as well as
the description of the galls on several of these plants.

Despite its wide distribution, the mite was not reported from plants other
than Centaurea spp. by the workers cited above. In the Review of Applied
Entomology (60 volumes 1913-1973) the mite was not mentioned. No reference to
the mite was found in "Insetti Dannosi all'Agricoltura" (della Beffa, 1961) or
in "Mites Injurious to Economic Plants (Jeppson et al., 1975). Since our
survey of the literature and the CIBC field survey showed the mite is not a
pest of cultivated plants or plants of ornamental importance, further testing

was in order.

49
FIELD TRIAL

In 1986 an open field trial was made in Greece using 6 native U.S. Cirsium
spp., 1 Greek Cirsium sp., and the oil-crop plant safflower (Carthamus
tinctorius) as test plants. This field trial was financed in part by an
extramural grant from the USDA-ARS Biological Control of Weeds Laboratory,
Rome, Italy, and was conducted by Dr. Byron Katsoyannos, Department of
Entomology, University of Thessaloniki, Thessaloniki, Greece.

The trial was set up in a randomized complete block design with 10
treatments (species of plants) replicated 10 times. The plant treatments in

the trial were:

1. Centaurea diffusa (control) Greek origin
2. Centaurea solstitialis (yellow starthistle) Greek origin
3. Carthamus tinctorius (safflower) oe Or. git
4. Cirsium creticum Greek origin
5. C. andersonii U,S.eOrie21n
6. C. brevistylum Deon Origin
7. C. cymosum Use. Orie2n
8.) C. occidentale UL Samora gin
9. C. pastoris Usow origin
10. C. undulatum U.5.. origin

The plants were infested by putting Centaurea diffusa galls containing

mites on the rosettes or growing points of the test plants.

50
RESULTS
At 6, 15, 24, and 32 days after the mites were placed on the test plants, 100%
of the diffuse knapweed and yellow starthistle plants in the trial had galls.
The yellow starthistle was less severely galled than the diffuse knapweed
control. None of the other plants in the test had galls or other evidence of
mite damage.
CONCLUSIONS

From the information available to date, we can say that Aceria centaurea
is stenophagous to the genus Centaurea, poses no apparent danger to safflower
or other cultivated crop or ornamental plants, nor to native North American
Cirsium spp. Further, there is no evidence that would make it suspect as a
pest of non-tested species of economic importance. The two native U.S.
species Centaurea rothrockii and C. americana were not available for testing.

Considering all these factors, I feel the mite does not pose a serious
threat to U.S. agriculture and is safe enough to introduce into quarantine in
the United States for an in-depth testing program to confirm its limited host
range and safety. Also, its possible impact on yellow starthistle and purple
starthistle will be explored. Permission is requested from the Technical
Advisory Group for the Biological Control of Weeds (APHIS) to introduce the
Pancidete mite into quarantine at Albany, California for further host

Specificity testing.

BIBLIOGRAPHY

Anonymous. Review of Applied Entomology, Series A, Agriculture, Vol.

1-61. Commonwealth Institute of Entomology, London.

della Beffa, G. 1961. Insetti Dannosi all'Agricoltura. Hoepli, Milano,

1106pp.

Henrick, F. 1966. Gubacsatkak Eriophyidae, Magyarorszag Allatvilaga

(Fauna Hungariae) XVIII Kotet (15 Fiizet):53.

Houard, C. 1908. Les Zoocécidies des Plantes d'Europe et du Bassin de la

Méditerranée. Vol.2 Dicotyédones 1248 pp. Hermann, Paris.

Houard, C. 1913. Les Zoocécidies des Plantes d'Europe et du Bassin de la

Méditerranée. Vol. 3 Supplement pp. 1249-1560. Hermann, Paris.

Nalepa, A. 1898. Eriophyidae (Phytoptidae), Das Tierreich (Acarina) 4.

Lieferung pp. 41. Verlag, Berlin.

Schroéder, D. 1977. Biotic Agents Attacking Diffuse and Spotted Knapweed
in Europe and their Prospective Suitability for Biological Control in
North America. pp. 108-131. Proc. Knapweed Symposium October 6-7

Kamloops, BC Canada, British Columbia Plant Science Head Committee.

Trstter A. end G. Cecconi, ca. 1903

Darwiotneceanl talica, Fasc. Vil No. 158. Fasc... 1X No. 22).

GREECE (R. Sobhian)

LEAFY SPURGE (Euphorbia virgata spp. complex)

Simyra dentinosa

A population of this insect was found feeding on Euphorbia seguieriana,
near Volvi Lake (ca. 40 km. east of Thessaloniki) in 1981. In 1983
preliminary studies in Greece showed that the female moth will oviposit on a
U.S. biotype of E. esula, and larvae can complete development on leafy spurge
plants of North American origin. Preliminary host specificity tests showed
that the host range of the insect is probably restricted to the genus
Kuphorbia (see annual report 1983), but since the insect was found on
Euphorbia seguieriana in Greece there was some feeling that it would not be a
promising candidate for biologial control of E. esula in the United States,
and thus no more attention was paid to the study of the insect for 2 years. I
suggested that we do a host specificity test of Simyra dentinosa in Rome in
1986 and provided them with Simyra eggs for the tests. The results were
promising so we decided to continue the host specificity testing and study the
biology of the insect in 1987. Over 2000 Simyra eggs and 400 E. seguieriana
plants (for control plants in the tests) were sent to Rome for the host
specificity testing.

The biology of the insect had been studied some in the previous years, but
it was not known where the larvae pupate or how they overwinter in the field.
In captivity they pupated on cage walls, among old food plants, paper towels,
etc. Extensive search for Simyra pupae around the host plants (root neck and
soil) or among various shrubs in the area was unsuccessful in 1983 and 1986.
Also, there was a paucity of information about natural larval mortality of the

insect.

Pupation Site

In order to find out where the larvae pupate in field, June 3 and 4 from
e200 to 715:00 hnrs,tdune Srfrom 12:30"°to 20r30 hrs™and June 6 fronm"G700) to
19:00 hrs were spent in the field watching mature larvae and trying to find
out what they do when they finish feeding, are ready for pupation and start
the rapid dispersal movement. The time spent in the field with the larvae
paid off. On June 5, at 18:30 I watched a mature larva as it fell from a
Euphorbia branch to the ground and crawled for about 1.5 meters in grass and
other weeds. It climbed a grass stem and stopped there for 35 minutes, after
which it crawled to another non-host plant (Capsella bursa pastoris Medic.)
and stopped there resting on a stem. The larva was observed for about an hour
while it stayed in the same spot, doing nothing. It was getting dark and a
cold wind was blowing, leaving the impression that the larva would stay at the
same spot overnight. Hoping to find it the next day the observation was
abandoned at 20:00 hrs. Next day, on June 6, at 08:00 observation at the same
location commenced. The larva was still resting on the same stem. The larva
had been emptying its stomach without feeding, and its body was more or less
translucent. At 09:05, when the temperature warmed up the larva crawled down
the stem to the ground and started moving rapidly towards a large Carduus
candicans W. et K. plant. It was moving at an unbelievable speed about 90
meters (0.9 kms.) per hour. After searching for about 10 minutes among the
old dry Carduus leaves, it left the plant and crawled to an Onopordum plant, 6
meters away from the Carduus plant, and started searching there again among
the old, dry, and twisted rosette leaves. At times. the larva would stop for a
few minutes inside the curled leaves. It was obviously searching for a
suitable location for pupation. After a while, it left the Onopordum plant

and crawled to a blackberry bush, where it stayed and searched for about 15

minutes.

Leaving this bush it crawled into a grainfield where I could not follow it
without disturbing it, so I returned the larva to the place where it had
started the journey in the morning. Again, it crawled toward the same Carduus
plant, as it had done previously and started searching among old dry rosette
leaves. It was difficult to follow the larva without disturbing it. Finally,
it became lost among the old Carduus leaves and other weeds, which formed a
dense mat of vegetation. Giving up the observations of this particular larva,
I started looking for another migrating larva. Fortunately one was found and
it was followed until it reached an Onopordum plant, where it started
searching among the old, dry, twisted, and curled leaves of the plant.
Searching for about 10 minutes, it found a half closed tube, formed by a
curled dry Onopordum rosette leaf. The larva entered the tube turning around
slowly, examining the hole. Finally it started to make a web and closed
itself in the tube by making a leathery silken cocoon inside the tube that was
not visible from outside, because it was covered with a coat of dry leaf
material. Searching among dry and twisted Onopordum leaves in the area for 10
minutes I found another cocoon and the question of the pupation site of Simyra
was definitely answered..,

Larval mortality: On May 18, 50 larvae of each stage (L

Mpa ah

a neh Set

Ly» L) were field collected and caged with fresh food, which was changed
every 3-4 days, until June 7, when they had all pupated. At the same time
(every 3-4 days) the cages were checked for cocoons of parasites which may
have exited from the the larvae. From May 24 to June 1, Apanteles wasp larvae
emerged only from the L, and Ly larvae, and formed clusters of cocoons.

The percentage of parasitism was low, only 7 (14%) of the 1 and 2 Ly

larvae were parasitized.

On May 28, 47 mature larvae were field collected and caged with fresh
food. All of them had pupated by June 3rd except for one larva which was
parasitized by Apanteles sp. A tachinid fly emerged from each of 3 Simyra
pupae on June 19. The rest of the pupae were kept for rearing adults.

On June 3 a large tachinid fly was observed ovipositing on a mature Simyra
larvae, in the field near Volvi Lake. The fly sat on a branch of the host
plant near a Simyra larva, and extruding her ovipositor laid one egg at a time
on an adjacent, accessible larva. There were 2 colonies of Simyra larvae on
separate Kuphorbia plants, about 2 meters apart. Each time the fly was
disturbed she left one of the colonies and flew directly to the other and
started to oviposit on larvae in that colony. Twenty mature Simyra larvae
were collected in the field and eheeced for tachinid eggs, which were visible
to the naked eye. The white eggs were similar to chicken eggs, in shape.

Five of the larvae (25%) in this group had been parasitized with the tachnid
eggs. Altogether, thirteen parasitized larvae were collected and checked
under the microscope for number of eggs and the position of the eggs on the
larvae. Nine larvae were parasitized with one egg/larva and these were
situated thusly: one with one egg on the head-capsule, one with one egg on
the dorsal side, and 7 with one egg on the ventral side. Two larvae had 2
eggs/larva, both on the ventral side. One larva had 3 eggs (all ventral) and
one larva had 4 eggs (all ventral). Most of the eggs were laid on the
anterior half of the larvae.

A group of 20 parasitized Simyra larvae were kept in a cage with fresh
food. They all made cocoons and pupated within 4 days. Seven adult tachinid
flies emerged from the cocoons between June 19 and 25 and were sent for

identification. Twelve cocoons found in the container were opened on July 3.

56
These are the results:

1 cocoon(s) contained a Simyra pupae

5 - - 1 dead fly/cocoon

4 a. 1 pupal exuvium of the fly in each
1 a ‘ 2 dead flies

il - 4 dead flies

Two pupal exuviae of the tachinid fly were found outside of the cocoons (the

larvae left the cocoons and pupated in the container).

Centaurea solstitialis Project (YST)

Bangasternus orientalis.

Adult weevils (more than 1,000 each year), were collected in the field in
Greece, and were released in the United States in 1985 and 1986. In 1987,
over 2,000 weevils were collected and sent to Albany, California for release.
The weevil became established during 1985-1986 in all release sites. At this
writing no information is available from the 1987 release. Due to the
successful establishment it was decided to make no further releases and wait
for the natural build-up of the population at the release sites.

Larinus curtus:

Adult Pestana! Since this insect is scarce and difficult to collect in
large numbers for screening tests, it was decided to rear the insect on caged
YST plants. Twelve YST plants were grown in a plot 2x2 m. On May 28 the

plants were caged in a 2x2x2 m. screen cage. At this time only a few of the

57
plants were budding so these buds were removed in order to be sure that no
other seedhead feeding insects were present in the cage to compete with L.
curtus. On June 24, 50 L. curtus adults were released in the cage. At this
time the plants were flowering. In the following 2 weeks the weevils were
mainly feeding or resting on the flowers and we were hoping to rear large
numbers of adults for our experiments in 1988. At the end of June the caged
YST plants were found to be infested with black aphids and all the plants had
dessicated by mid-July. Obviously the cage had protected the aphids from
their parasites and predators and allowed the aphids to build up a damaging
population. Six seed head samples of 20-150 heads each sample were collected
and examined for the rate of infestation from July 21 to September 22 and only
2 larvae and ll weevils were alive or had emerged. The results of the
dissection and examination are given in Table l.

Lack of pollination and early death of the plants were probably the
reasons why the number of adults produced was so low. It seems that
pollination and the subsequent development of achenes is essential for the
development of the larvae, because many dead larvae were found in the seed
heads with infertile and undeveloped seeds.

Host Preference: When L. curtus adults, labelled with nail polish,
were released in an experimental field plot in Thermi, some adults were found
on safflower as well as on YST Biante Following the above observation, a

preliminary host preference and oviposition test was carried out in Thermi.

give B.I. Katsoyannos, 1986 "Open field host selection test in Greece using
three indigenous arthropod species and several North American species of
Cirsium thistles". USDA-ARS grant No. 59-32U4-6-86.

fod

Table 1. Results of attempt to rear Larinus curtus on YST in a large field cage.

No. seedheads Larvae Pupae Adults
DATE examined alive dead frass only alive dead alive dead emerged
July 21 20 ~ 3 - 2 os = = ss
August 23 50 - 8 - - - 1 - =
August 14 30 - al - - - 2 i ~
August 27 50 BB Ha LaNe ts sugiheubome Soe belzuwell
September 7 99 - ol 3 ~ ~ 2 - 4
September 22 50 - 5 2 = = = = l
TOTAL 29g - 52 8 2 1 6 2 5

J/ Sterile undeveloped achenes in these heads.

On July 16, 1 male and 1 female weevils were caged on YST (no choice
treatment 1), on safflower (no choice treatment 2) and on YST-safflower (two
choice treatment 3) for host preference trials. There were 2 flowers of each
test plant in each cage, and each treatment was replicated 4 times. The
flowers were kept as bouquets in vials with water. The bouquets were checked,
5 times on the first day (at one-hour intervals), 3 times on the second day
and once on the third day. The number of adults seen on the flowers was
recorded at each observation. The results are shown in Table 2.

The adults preferred the YST flowers, but they also were found on
safflower flowers, even in 2-choice experiments. The adults fed on both YST
and safflower flowers. The amount of feeding was not quantified.

On July 20 and 21, all the flowers exposed to the adults were dissected
under a stereomicroscope and checked for presence or absence of L. curtus
eggs. The results are shown in Table 3.

No eggs were found in safflower flowers in either the no-choice or
two-choice trials, but 26 eggs (16 no-choice and 10 two-choice) were found on
YST flowers. Up to 5 eggs were laid in one YST flower head, and by July 21
all the eggs had hatched and the larvae were feeding on the achenes in the YST
flowerhead.

On the YST plants the ovipositing females insert their abdomen or
sometimes nearly their whole body into the YST flowers and deposit their eggs
inside the florets, near the developing achenes. On safflower flowers the
bracts keep the entrance to the capitulum so tightly closed at the apex that
the weevil cannot enter the florets with her abdomen or body to find a
suitable oviposition site, thus physical structure of the safflower flowers

does not permit access to the florets, which is necessary for oviposition.

60
Table 2. Number of L. curtus adults observed on safflower and YST in a

no-choice and 2-choice host preference (A) oviposition (B).

NO CHOICE TWO CHOICE
No. replicates YST SF SF LSE
No. of adults observed No. of adults observed
on the flowers on the flowers

in each replicate: in each replicate:

1 8 ff O aa

2 12 5 4 ih

3 14 i p aa

: ts a Ba ne

TOTAL aye 28 8 37

Tables. Number of L. curtus eggs found in YST and safflower in a no-choice

and 2-choice host preference-oviposition trial.

NO CHOICE TWO CHOICE
No. replicates YST SF SF YST
No. of eggs found in No. of eggs found in

each replicate each replicate

1 ui e) fe) al

2 3) fe) 0 4

5 8 fe) 0 A)

4 2 QO 0 4

Field Trial (Safflower):

On July 18, 25 L. curtus adults were labelled with nail polish and
released on a small plot of safflower (10x3 m) at the University Farm at
Thessaloniki. Most of the flower heads were in the post-flowering stage,
however, some flowers were present. On July 19 the flowers on the edge of the
plot were checked and 3 of the labelled L. curtus adults were found on then.

Collections for Albany and Rome: Two hundred L. curtus were field
collected and sent to Albany for host specificity tests, and another 200 were
collected by Paul Dunn and Luca Fornasari and me for experiments in Rome.

Kustenopus villosus:

Rearing adults on caged YST: The objective of the study was to rear large
numbers of E. villosus adults for various tests and future releases.

Nine YST plants were grown close together in a plot lxl m. The plants
were caged on June 9 in a black screen cage placed on a metal frame. All buds
were removed in order to elimimate any other seed feeders which may have been
present as larvae in the buds. On June 25, 30 E. villosus adults were
released in the cage. At some point, the cage wall was damaged so parasites
and tephritid flies entered the cage and nullifying the rearing experiment.

One hundred seed heads were collected from the caged plants on September
8, examined externally for oviposition sites, and dissected under a
stereomicroscope to determine the rate of infestation with the following

results.

The Eustenopus data are:

11 seed head(s) with living adults

rel oe a with dead adults
sjep it from which probably adults emerged
Bs hee C with dead pupae
ile, . feeding signs only (larvae missing)
1 as . dead larvae
Widget parasitized larvae

Other findings:

Five seed heads with Isocolus galls, 3 seed heads with tephritid pupae,
15 parasitized Eustenopus larvae, and 10 seed heads with Lasioderma sp.
(Colep.)

To find out where the adults overwinter, the cage was removed and the
plants and soil in the cage were searched for adults. One adult was found on
a twisted paper towel which had been put in the cage 2 weeks previously and 6
adults were found in the soft soil within the cage. The adults were
motionless but alive.

It is now clear why the adults that appear on plants in early Spring are
very often covered with mud.

Field Collections:

On September 9, 100 YST seed heads with at least one oviposition/feeding
scar/head were collected in the field near Thermi. The seed heads were
examined externally for number of oviposition/feeding scars and dissected
under a stereomicroscope to determine the fate of the larvae. Ninety nine
seed heads had one oviposition site each and 1 seed head had 2. The following
are the results:

2 seed heads with living adults

ipa: "from which adults probably emerged
4.8 "with parasitized pupae
22 al "with parasitized larvae
Hirbeay "dead larvae
siete # "missing larvae

To determine if some adults overwinter in the seed heads, a sample of 100
seed heads was collected and examined on September 28. Hight adults were
found in 8 seed heads, empty pupal cells were found in 44 seed heads, and 48
heads were uninfested. Adults (440) Eustenopus villosus were sent to Albany,
California for their studies and another (670) were collected by L.
Fornasari, Paul Dunn and me near Thessaloniki.

Chaetorellia hexachaeta:

Three thousand five hundred Centaurea cyanus seed heads infested with C.
hexachaeta were collected and sent to Albany, California on June 2. The
emerging adults were used to complete host specificity tests. Since no
negative results have been obtained, C. hexachaeta will probably be released
in the United States, against YST, in 1988 (C. Turner pers. comn.)

Field Trial (Multiple Candidate)

Preparation of a field experiment to determine host specificity of Larinus
curtus, Urophora sirunaseva (candidates for control of yellow starthistle),
and Larinus minutus (a candidate for biological control of Centaurea maculosa
and C, diffusa). The latter species, common in northern Greece, has been
under study by CIBC, Delémont for the past 3 years. Clive Stinson, the
scientist in charge of the CIBC project agreed to provide a technician to help

carry out the experiments in 1988.

Objectives: (1)
behavior of 3 insect
exposed equally to 7
demonstrate the host
the number of adults

species in the test.

64
To determine the dispersal, attraction and oviposition
Species (ep CUdmucr L. minutus and U. sirunaseva) when
Selected plant species-in a field experiment. (2) To
specificity of each of the 3 insect species by recording

which emerge from the harvested seed heads of each plant

Procedure:

1. A “Randomized Complete Block Design" experimental plot was established
at the University Farm, Thessaloniki, consisting of 7 treatments replicated 7
times. (see design figure l).

2. The size of each treatment block was 2x2 m.

3. Each treatment block will contain 3 individual plants of the species
designated for that treatment block, planted equidistant (40 cm. between
plants) in a triangular pattern in the center of each block.

4. The plant species to be used in the experiment were selected on the
basis of (a) taxonomic relationship, (b) native plant consideration,

5. Plants designated in the design as "A" safflower (cultivar Hartman)
and "D" artichoke (var. Green Globe) were provided by the USDA-ARS laboratory
in Albany, California; all others were supplied by the USDA Thessaloniki
Laboratory from local sources.

6. All plants to be maintained in good condition during the time that the
experiment is being conducted.

7. L. curtus adults will be collected on YST, males and females will be
separated and labelled with different colors. Two beetles (1 male, 1 female)
will be released in the center of each block (total of 98 weevils to be
released).

In early spring, before U. sirunaseva emerges, 100 YST seed heads,
infested with U. sirunaseva will be placed in the center of each block, so
that the emerging flies will have free choice of host plants from the

available test and control plants.

L. minutus adults will be collected on C. diffusa and C. maculosa, sexed
and labelled with different colors according to host plant from which they
were collected, allowing the investigators to keep track of the two biotypes
and find out if there are any differences in their dispersal and host
selection. Two beetles of each biotype (2 males, and 2 females) will be
released in the center of each block (total of 196 weevils to be returned to
the plot).

8. The day after release, weevils in each block will be examined for (a)
presence or absence of weevil (by color) on the test plants; (b) the presence
‘or absence of oviposition and/or feeding behavior (by color). Observations
will be made again 3 days after the release, then once weekly during the
oviposition period of the beetles.

Q. Behavior of U. sirunaseva and presence or absence on the test plants
will be recorded at each observation.

10. As soon as mature flower heads (post-flowering stage) appear on the
test plants they will be collected and all the heads from each plant bagged
together to capture the insects as they emerge. This procedure will be
repeated once weekly until the end of the season when no more flower heads are

produced by the test plants.

1-7

Fig. 1. Plot Plan of Randomized Complete Block Design For 1988 Field
Trial of Larinus curtus, Urophora sirunaseva and Larinus minutus

Block size 2 x 2 meters.

REPLICATES

TREATMENTS Pee eae 3 4 5 6 7

I BL/ F p2/ C ql/ B A
midniacsek fo vee tac Pievuaab Hegomead so’ Bole SARME: o} Sevan. to gens ee
eur iakiet ls. py Golple ceteten hone | snd NBs Wwe td Biba kee ies oe
i |. mY Ma AewuntwbeeAtcOy metas Oi peceaelr aes ae
MENG Vie tals hit she Ciaineiedle Be wey MELO Pew “ad: ein? a. ae ae
A twteds (al the Gas patos &: Matt) Ay pe, 9p cy) aR et aa)
ibbacat Néenivoetion? i Wevatawek .6.0) eee Re ae roe 2 ae

1/ Centaurea diffusa (B), Centaurea maculosa (G), and Cynara scolymus

(D): These species have been grown in their corresponding blocks on
Oetover 12,1937.

- Replications

I-VII - Treatments

[ei cs} {esl eh Sy ie)

- Carthamus tinctorius (cultivar 4440)

- Centaurea diffusa (Greek biotype)

- Centaurea solstitialis (Greek biotype)

- Cynara scolymus (U.S. Green Globe)

- Cirsium creticum (Greek biotype)

- Helianthus annuus (sunflower, Greek variety)

- Centaurea maculosa (Greek biotype)

68
11. All weevils and all Urophora flies will be pinned and labelled with
(a) replicate number, (b) treatment and (c) date of seed head collection, (d)
locality, then sent to specialists for identification. Since U. sirunaseva
overwinters as mature larvae, all flower heads collected from July to
September must be kept in a protected place until the adults emerge in the
spring of 1989.
12. Analyze and interpret data when determination of insects is
received. Plant species to be tested in design:
A. Carthamus tinctorus (Cultivar Hartman)
B. Centaurea diffusa (Greek biotype)
C. Centaurea solstitialis (Greek biotype)
D. Cynara scolymus (U.S. Green Globe)
E. Cirsium creticum (Greek biotype)
F. Heliathus annuus (Greek variety) sunflower

G. Centaurea maculosa (Greek biotype)

DIFFUSE KNAPWEED PROJECT - Centaurea diffusa

INTRODUCTION

Bangasternus fausti

Assistance was given to Gaetano Campobasso, who came to Thermi to collect
B. fausti weevils to complete the host specificity testing in Rome.

EXPERIMENTAL OBJECTIVES

1. To determine if the eggs of B. fausti are parasitized.

2. To study (a) the degree of natural mortality and (b) the seed
consumption (destruction) by the weevil.

MATERIAL AND METHODS

la. About 200 B. fausti eggs were collected in Thermi on June 10 and kept
on moist paper towels in a petri dish in our laboratory in order to capture
emerging parasites.

lb. Another sample of about 500 eggs collected with Paul Dunn and Luca
Fornasari were taken to Rome to check again for egg parasites.

2. Five seed head samples (100-105 mature seed heads infested with at
least one B. fausti egg per sample) were collected from August 2 to September
20 in Thermi and dissected under a stereomicroscope. Table 4 shows the
results of the dissections.

RESULTS

In trial l(a) with 200 eggs, some of the eggs hatched, but no parasites

emerged from them. In trial 1(b) with 500 eggs about 60 % of the eggs hatched

but no parasites emerged.

Table 4. Natural mortality rate of B. fausti at various stadia and rate of seed destruction.

Date ; NO. OF HEADS : EGGS i LARVAE 2 PUPAE 5 ADULTS

Collection:!Collected Infested Not !l/Head 2/Head No. No. Not ‘Alive Parasit. Missing:Alive Parasit..Emerged In Heads;

2 Infested. Eclosing Eclosing: or Dead 5 :
August 2 103 85 18(135)2/ 95 8 77 34 10(°) 24(18) 27 3(*) 9(°) 0 2(°)

: : |
Y= 7.5 X = 0.75 |

FIRSIS SRO RO AUR TIC ODO OOO COCCI ODU GOO OOCDEUTCOUC COSCO OOO UIGOOIC CODCOD OCR UIC OCC COUR OOOO SO GOO OSI OI 0) BOO IO I VO OIE I I

August 14 99 78 21(180) 98 7 53 48 nC) MEX) ng () 23(°) aC) |
x = 8.5

Wralale clcele aie Ceraioic ule ele eis e/olele clslalsisicia 6's cle 6(6.0.6'6 S/¢\0' 014. 0\o10's|6 0 (00 01610)e'6 14 810(0 e101 010 2 8'0\010 0/0 © 018 0.0/0. e 010 0/08 0 6'6 0.6 01 8.0 0,.0-615 6.0 SSS 0,8 os ie ie ake e ee eae ae acee

August 26 100 72 28(175) 100 ) 60 40 (e) TANG) 19 (0) 22(°) 2 (a) ro)
X = 6.2 |

ABAD OOUOCDODO DODO DOO OD COCODODUOOCU GC DUOUOCODOOLOOUC OCC OOOO ICO OO COOK SOK CH ROR ICA SIO EBT II NIETO OILS

September 11 100 100 0) 94 6 48 57 0) 19(4) 16 0) 12(7) 0) Oo |

x = 0.2

September 20 100 99 0 94 5e/ 53 55 0) 24(5) 10 f°) 16(*) fe) fe)

=
x = 0.2
AOS OOOO OOO DOO COUODOIOOD DUO CO OOOO ICO OO KCI A INO OI COICO ICIS ORCI SOOO ICSC HOI TOOT HORI SOOR RCE ISIC BCS EON IE IS III =

( ) = No. of seeds/heads in that category
SASS No. seeds/head

2/ 1 seed head had 3 eggs on it.

re:

In 97 seed heads, where an adult or a pupa developed, no seeds were
found. The developing larvae fed on the seeds, pappus hairs, and receptacles,
leaving only the bracts, inside of which the larvae made pupal cells.

In 105 seed heads, in which larvae were found (alive, parasitized, dead),
only 27 seeds were found (x = 0.25 seeds/head). In 67 uninfested seed heads
490 seeds were found (x = 7.3 seeds/head).

Pterolonche inspersa

P. inspersa eggs were collected for shipment to Albany, California to
infest C. diffusa rosettes in the U.S. and start a colony of the insect in
California. On July 29 and 30, 260 C. diffusa roots infested with P. inspersa
were collected around Kardia (near Thessaloniki). About 30% of the adults had
already emerged, 30% were pupae and 40% were still in larval stages. The
infested roots were placed in moist soil under 3 screen cages CixixiimS)icin
the field at the University Farm at Thessaloniki. Several potted C. diffusa
rosettes were placed under the cages to serve as an oviposition substrate for
the emerging adults. Adults started to emerge on August 2 and oviposition
started on August 3 and 4. Most of the eggs were laid on cage walls, and were
difficult to collect. Only 160 eggs were collected on August 5, 100 eggs on
August 6, and 25 eggs on August 10. Fortunately, a good population of
C. diffusa was found around Kardia, on which P. inspersa eggs were common, so
over 6000 eggs were collected from this location between August 7 and August
17. These were sent to Albany along with the eggs collected from the cages
(total 6,635). On August 10, 50 of the field collected eggs were examined and
15 (30%) had hatched.

Aceria centaurea

We were requested to send a sample of the diffuse knapweed gall mite

(Aceria centaurea) to Albany to start host specificity tests.

Also, Dott.ssa. Marisa Castagnoli, an Italian eriophid specialist in
Florence, has agreed to collaborate with us and wanted a colony of the mite to
Study its biology. The mite colony near Arnea where it has existed for the
past few years was visited on May 13 and 25, June 8, 22, and 27, and July 17
and 30, and no diffuse knapweed infested with the gall mite could be found in
the area. When collecting Bangasternus fausti around Thermi and collecting
Pterolonche inspersa larvae and eggs around Kardia no gall mite infestation on
C. diffusa was seen. However, another Aceria mite was discovered attacking
meristem tissue of C. diffusa plants, turning the growing points into
“witches'-brooms", which produced very small flower heads with no seed or just
a few deformed or poorly developed seeds per seed head. This mite was first
found on May 25, 1987 near Arnea at the Junction to Riza. In that report it
was called a bud mite because it was common on the bracts of the young flower
buds or on axillary buds throughout the season. The mite was also common in a
dense population of C. diffusa along the main Thessaloniki-New Mudania road,
near Kardia. Two samples of this mite were collected on August 11 and 17 for
shipment to Albany, California. Samples of the mite were collected for
identification, and given to Dott.ssa Castagnoli.

Some of the infested plants with the witches'-broom dry out and die during
the summer and fall, while others give rise to secondary growth from the root
neck. A sample of 8 "witches'-broom" plants and 25 rosettes were collected
from the location near Kardia on August 19 and checked for the mite. All the
plants were infested except 3 rosettes. Older rosettes with many dry leaves
were more heavily infested. Very small rosettes with just a few leaves also
were infested. On rosettes, the mites were found between the leaf petioles
around the root neck, and among the small axillary buds and young flower buds

of the old plants. A sample of 8 old plants with secondary growth and a

———

We
Sample of 12 rosettes were collected on August 28 near Arnea and examined for
the presence of the "bud" mite. All the plants were infested, except one
rosette. On September 14 a sample of 16 old plants and 12 rosettes were
collected near Kardia and examined. All the plants were infested with the
mite.

The same day a one-hour search for the gall mite was made at the location
near Kardia. Only 4 infested C. diffusa rosettes could be found. On
September 17, the location near Geroplatanos was visited, and in the
fifty-minute search, only 6 rosettes infested with the gall mite could be
found. Toward the junction to Riza a fallow wheat field was found, in which
many C. diffusa rosettes were found to be infested with the gall mite.

| On October 8, when Dott.ssa. Castagnoli visited our laboratory we went to
the field and collected samples of the gall mite as well as the bud mite. She
examined the samples in the laboratory and was very interested in getting
living material of both species for her studies. Next day, on October 9, I
collected 50 C. diffuse rosettes infested with the gall mite and 50 rosettes
infested with the bud mite at the location near Kardia. The material was
hand-carried by Dott.ssa. Castagnoli to Florence to study the biology of both
species as well as to confirm their identity.

The bud mite is more common and more effective than the gall mite. In 50
seed heads collected from infested witches’ broom Cc. diffusa plants, at the
junction to Riza, only 37 seeds could be found (x = 0.7 seeds/head). An
infested plant has many seed heads, most of which are so small that no seeds
develop in them. At the same time these plants bear a few larger heads in
which some seeds are found. The mite generally alters the plants' morphology,
the distance between the axillary buds on infested plants becoming reduced and

the whole plant being considerably deformed.

EXPLORATION: Large infestiations of both Eustenopus villosus and Larinus
curtus are difficult to find in northern Greece, therefore, it was decided to
search for new locations where larger numbers of adults could be collected in
the future. A three-day trip to eastern Greece, (Alexandropoli and Ardanio)
from July 7 to 9 and 4 half-day trips around Thessaloniki, in mid-June
revealed a few good locations. On the trip to eastern Greece 25 locations
were checked for presence of the two insects. L. curtus, found on ll
locations, was rare in 9 locations (a 30-minute search yielded 1-4 adults) and
common in 2 locations (in 10-minute and 30-minute searches, 21 and 13 adults
were found). The two good locations are 16 km. east of Kavala (800 meters
west of the junction to Nea Komi and 44 kn. east of Kavala, junction to
Thalasia).

E. villosus was found in 7 locations. One location was 44 kms. east of
Kavala and all other locations were around the village Ardanio (12 km west of
the Turkish border). The weevil was common only at one location, where 41
adults were collected in 30 minutes searching. In the other locations 1-10
adults were found in the 30 minutes spent searching each location. Dyer 30
new locations were examined around Thessaloniki. Only in one location were
good populations of both insects found. This location is on the
Thessaloniki-Oreokastro road (north-east of Thessaloniki). L. curtus was
present in nearly all locations around Thessaloniki but was rare (1-5 adults
per half hour search). E. villosus also was more or less common along the
same road to Oreokastro.

MISCELLANEOUS:

le-s.S. oCirsiumsingvitro:

A shipment of U.S. Cirsium plants, grown by tissue culture and still in

vitro, were shipped from the Rome laboratory to Thessaloniki. It was an

i
attempt to provide plants for transplanting in soil to be used in various
experiments in the future. The shipment arrived in Thessaloniki with 2 days
delay (sent air freight by Olympic Airline). Following the delay it was a
weekend and we could not get the plants because the customs office was
closed. Finally on Monday, May 18 the shipment was retrieved from the
airport, but by this time the plants were yellowish and some were dead. On
May 19, 1986 60 of the best looking small plants were transplanted into small
pots and kept in transparent plastic bags in a shady room. Preparation of
soil, pots, plstic bags, shady place, etc. were according to instructions but
all plants died within 3-4 weeks. A few plants produced new small leaves but
they died later. Most probably failure of the attempt was due to the long
time en route.

Cooperation with CIBC, Delémont: A sample of several hundred mature
C. cyanus seed heads infested with Chaetorellia hexachaeta collected from
Agios Prodromos and 500 mature seed heads of Mantisalka salmantica collected
near Thermi, were sent to Delémont on June 1, 1987. Also, 600 Larinus minutus
ee were collected near Thermi on Centaurea diffusa and near Triadi on
Cc. maculosa, and were sent to Delémont on June 23, 1987.

Cooperation with CSIRO, Montpellier: Four samples of Chondrilla juncea
seeds for use in isoenzyme studies were collected, (30 kms south, 30 kms
north, 30 kms east of Thessaloniki and one sample near Thessaloniki) in
September and October 1987. Over 20 seeds per individual plant were collected
from 20 to 28 separate plants at each location and were mailed to CSIRO on
October 13, 1987. In the course of the seed collection the larvae of a

tephritid fly was found feeding in the seed capsules of the C. juncea plants.

76
About 15 adults of the fly were reared out. They are probably known to CSIRO
researchers. If not it might be worthwhile to identify the species and see if
it is specific to C. juncea. We plan to send a few pinned specimens of the
fly to Montpellier

A Lepidopteran larva also was found feeding inside the seed capsules.
After the larva cleans out a seed capsule it leaves it and penetrates into
another one. In this way each larva destroys several seed capsules. About 20
larvae were collected and provided with fresh food in the laboratory. Four
larvae pupated in the sand placed in the cages with the food plants.

C. juncea populations were examined for rust infection in 9 locations
along the road from Kavala to Ardanio and Sufli (eastern Greece) and at least
15 locations around Thessaloniki, Drama, Halkidiki etc. Only individually
infested plants were found in several locations, but these were not collected.

Cooperation with the University of Thessaloniki: Necessary assistance was
provided to Professor Katsoyannos in his field experiment with the host
specificity test of L. curtus in Thessaloniki (collecting weevils, taking care
of plants, taking data etc.). He will present the results of the trial in his
final report. Assistance was also provided to I. Pittara for finishing her
doctoral thesis on the behavior and biology of C. hexachaeta.

A prefabricated building to serve as a laboratory is being donated to the
Department of Entomology by the U.S. Department of Agriculture, ARS, in
appreciation for housing, rent-free, for 7 years the Rome laboratory's program
in Greece. The building will become the property of the University of
Thessaloniki a soon as it is built but ARS has guaranteed use of the building
for 5 years after its completion with an optional 3 years’ use if necessary.
Space for one Greek scientist is provided in the building from the day

construction is completed.

10.
ils
12.
13.
14.

16.

las

18.

ths

Shipments - Insects, plants and plants parts:

March 30
Apri 22
May 27

June l

June 2
June 2
June 8
June 23

June 24

June 24
June 29
June 30
July 20
August 11

August ll

August 18

Euphorbia seguieriana-400 plants to Rome

Simyra dentinosa-2,000 eggs to Rome

Bangasternus fausti-1,500 adults to Rome

Samples of Centaurea cyanus and Mantisalka salmantica seed
heads to CIBC, Delémont

Bangasternus orientalis-2,050 adults to Albany, California
Centaurea cyanus-3,500 seed heads to Albany, CA.

a sample of C. diffusa infested with Aceria sp. to Rome
Larinus minutus-600 adults to CIBC, Delémont

A sample of C. diffusa plants infested with Aceria sp. to
Albany, California

Eustenopus villosus-440 adults to Albany, California
Eustenopus villosus-550 adults to Rome

Larinus curtus-200 adults to Albany, California
Eustenopus villosus-170 adults to Rome

Pterolonche inspersa-2,285 eggs to Albany, California

A sample of C. diffusa plants infested with Aceria sp. to
Albany, California

P. inspersa-4,3550 eggs to Albany, California

A sample of C. diffusa infested with Aceria sp. to Albany,
California

tephritid flies-114 specimens YST to Il. White, British

Museum, London

19.

20.

October 9

October 13

C. diffusa-50 plants infested with Aceria sp. (the gall mite)

and 50 plants infested with the Aceria bud mite to Dott.ssa.

Castagnoli, Florence.

C. juncea-4 seed samples to CSIRO, Montpellier.

‘ie

PUBLICATIONS

GREECE

D. M. Maddox and R. Sobhian. 1987. Field experiment to determine host

specificity and oviposition behavior of Bangasternus orientalis and

Bangasternus fausti (Coleoptera: Curculionidae), biological control

candidates for yellow starthistle and diffuse knapweed. Env. Entomol. 16
(3) 3645-648

R. Sobhian and I.S. Pittara. A contribution to the biology, phenology
and host specificity of Chaetorellia hexachaeta Loew (Dipt. Tephr.), a
possible candidate for the biological control of yellow starthistle

(Centuarea solstitialis L.). JZ. Ang. Entomol., in press.

Mareh 2-3

April 21-24

April 22-23

May 11-12

May 18-28

May 22-23

May 29-30

June
June
June
June
June
June

June

July
July

July

aha)
8-10
15-18
15-21
17-23
22-50

25-30

29-July 7

30-July 16

(Ge,
7-10

August 19-20

TRAVEL (ROME)

P. H. Dunn, G. Campobasso, L. Fornasari, T. Mimmocchi,

M. Stazi, M. Cristofaro, P. Pecora to Antibes to attend

the joint CIBC/CSIRO/BCWLE-ARS-USDA/IPP-University

Zagreb meeting.

G. Campobasso - Bari

M. Cristofaro - Perugia/Pisa

M. Cristofaro and P. Pecora - Pisa

G. Campobasso =- Greece (Thessaloniki & vicinity)

M. Cristofaro and M. Stazi - Pisa

P. Pecora - Perugia/Pisa/Bologna

M. Cristofaro and M. Stazi - Pisa

L. Fornasari - Palermo

P. Pecora and A. Laregina - Vienna, Austria.

M. Cristofaro and M. Stazi - Lucca/Piacenza/Pisa

P. H. Dunn and L. Fornasari - Greece (Thessaloniki &
vicinity )

G. Campobasso - Bari

P. Pecora and A. Laregina - Vienna, Austria and
Budapest, Hungary

M. Cristofaro and M. Stazi - Lucca/Pisa

R. Sobhian - Fanari, Alexandroupolis, Greece

M. Cristofaro and M. Stazi - Pisa

M. Cristofaro and M. Stazi - L'Aquila

81
September 21-22 M. Cristofaro and M. Stazi - Pisa
October 4-31 P. H. Dunn - U.S. (Home leave and consultation at

Beltsville and Albany)

October 8-12 G. Campobasso - Bari
October 11-22 M. Cristofaro and P. Pecora - Romania, Austria,
Czechoslovakia

November 4-5 M. Cristofaro and M. Stazi - Pisa

March 6
March 11
May 13
May 25
June l
June 6
June 12
June 19
June 24
July 1
July 6
July 9
July 13

JUL ye

April 27
May 7
May 13
May 13
July 8

sept. 2

N° SHIPPED

700
10,000
140
317
350
250

210

35
3,100
2,402
40

190

1,580

many
ca 150
ca 150
many
5 000

ca 150

SHIPMENTS
ROME LABORATORY

SPECIES SHIPPED

INSECTS
Eteobalea serratella (in roots)

Dasineura capsulae (larvae)

Bayeria capitigena (galls)
Bayeria capitigena (galls)
Bayeria capitigena (galls)

Bayeria capitigena (galls)
Tyta luctosa

Oberea erythrocephala
Aphthona czwalinae
Aphthona flava

Aphthona cyparissiae
Oberea erythrocephala
Aphthona cyparissiae

Aph thona flava

BOTANICAL MATERIAL
Uromyces scutellatus (spore)
Cirsium douglasii (in vitro)
Cirsium douglasii (in vitro)
Uromyces scutellatus (spore)
Centaurea alba (heads)

Cirsium andrewsii (in vitro)

DESTINATION

Delémont, CH

Albany,
Albany,
Albany,
Albany,
Albany,
Albany,
Albany,
Albany,
Albany,
Albany,
Albany,
Albany,

Albany,

Ft. Dietrich, MD
Delémont, CH
Thessaloniki, GR
Ft. Dietrich, MD
Delémont, CH

Delémont, CH

10.

ste

13's

14.

Loe

TO.

els

83
VISITORS
(in order of visit)

ROME LABORATORY

Dieohen Ls. Perkins, USDA, ARS, EPL, Paris.

Dr. Antonio Quacquarelli, Phytopathology Institute, Ministry of Agriculture
and Forestry, Rome.

Dott.ssa Paola del Serrone, Phytopathology Institute, Ministry of
Agriculture and Forestry, Rome.

Dr. Dieter Schoeder, CIBC Biological Control Laboratory, Delémont
Switzerland.

Dr. Pier Luigi Pasqualetto, University of Pisa.

Dr. Joe McCaffery, Department of Entomology, University of Idaho, Moscow.
Dr. Ken Hagen, Professor, Department of Biological Control, University of
California, Albany.

Dr. Jerry Onsager, USDA, ARS, Grasshopper Laboratory, Bozeman, MT.

Dr. T.J. Army, Deputy Administrator, NFS, Beltville, Md.

Mr. U. Schmetzer, European Correspondent, Chicago Tribune, Rome.

Professor G. Prendeville, Plant Science Department, University College,
Cork, Ireland.

Dr. Max Whitten, Chief, Division of Entomology, CSIRO, Canberra, Australia.
Dr. C. J. DeLoach, USDA, ARS, Temple, Texas.

Dott.ssa Marisa Castagnoli, Istituto Sperimentale per la Zoologia Agraria,
Firenze.

Dr. William Bruckart, USDA, ARS, Plant Disease Research Laboratory, Ft.
Dietrich, Frederick, Md.

Dr. Ray F. Moore, USDA, ARS, EPL, Béhoust, France.

Dr. George Schiebelreiter, Neulengbach, Austria.

INSECTS SENT FOR IDENTIFICATION

ORIGIN SHIPMENT N° IDENTIFICATION |

Parasites from 87-1 Braconidae: Cotesia sp. possibly

Simyra dentinosa vanessae (Remhard). Det. P. M. |
Marsh

Cecidomyiids from 87-2 Cecidomyiidae: Dasineura sp. not

leafy spurge capsulae. Det. R. J. Gagné

Cheilosia sp. (larvae 87-3 Not yet determined

from Cirsium palustre
and C. oleraceum collected

by Zwolfer in Germany

Tachinid parasite of 87-4 Not yet determined

Simyra dentinosa

| - | == Bons xed =a See i ol eee ca a

Distribution list of annual report (partial)

Agricultural Counselor, American Embassy, Rome, Italy

Agricultural Counselor, American Embassy, Athens, Greece

Andres, L.A., Albany, CA

Asian Parasite Lab., Seoul, Korea

Belcher, M., Librarian, Keith Turnbull Research Institute, P.0.Box 48,
Frankston 3199, Victoria, Australia

Biological Control Laboratory, Beijing, PRC

Boldt, P.E., Temple, TX

Bovey, R., College Station, TX

Buckingham, G.R., Gainesville, FL

Bruckart, W., Frederick, MD

Callihan, R.H., Chair, Technical Advisory Group on Biological Control of Weeds,
Moscow, ID

Carl, K., Delemont, Switzerland

Castagnoli, M. Istituto Zoologico Sperimentale, Florence, Italy

Christy, A.L., NPS, Beltsville, MD

CIBC, Trinidad, West Indies

Clement, S.L., Plant Germplasm Research, USDA, ARS, Pullman, Washington
NAL, Beltsville, MD

Commonwealth Istitute of Entomology, London, England

Cordo, H., Hurlingham, Argentina

Coulson, J.R., ARS Biological Control Documentation Center, Beltsville, MD

CSIRO, Biological Control of Weed Unit, Montpellier, France

Cunningham, G., Animal and Plant Health Inspection Service, Hyattsville, MD

Da Re, G., Stazione Forestale di Bosco Mesola, Ferrara, Italy

Defago, G., Zurich, Switzerland

86
De Loach, J., Temple, TX
De Marinis, A., Tenuta di San Rossore, Pisa, Italy
Drea, J.J., Beneficial Insects Laboratory, Beltsville, MD
Dowler, W.M., Frederick, MD
Domenichini, G., Universita Cattolica, Piacenza, Italy
Emiliani, G., Director, Tenuta di Castel Porziano, Rome, Italy
Fuester, R., Newark, DE
Gordh, G., Dept. Entomology, UCR, Riverside, CA
Greathead, D., CIBC, England
Harley, heles., CSIRO, Australia
Harriss be, Saskatchewan, Canada
Hawkes, R., Oregon
Hunter, <C., Sacramento, CA
Jessep, T., Christchurch, New Zealand
Kilic, U., @Ankara, Turkey
Kovalev, 0., Leningrad, USSR’
Klassen, W., NPS, Beltsville, MD
KincaidwD.R<, Beltsville, MD
Lavigne, R., Wyoming
Maceljski, M., Zagreb, Yugoslavia
Maddox, D., Albany, CA
Malva, C., International Institute of Genetics and Biophysics, CNR,
Naples, Italy
Matthews, FAO, Rome, Italy
McCarty, M.K., Lincoln, NE
Mayerdirk, D., Animal and Plant Health Inspection Service, Hyattsville, MD
Miller, Dok saweokl. Beltsville, MD

Mohyuddin, I., Rawalpindi, Pakistan

87
Moran, V.C.,Faculty of Science, University of Cape Town, Cape Town,
South Africa
Naumann, R., Bielefeld, West Germany
Nowierski, R., Bozeman, MT
Moore, R., Paris, France
Pschorn-Walker, Kiel, West Germany
Quacquarelli, A., Istituto Sperimentale per la Patologia Vegetale, Rome, Italy
Quimby, P., Stoneville, MS
Rees, N., Bozeman, MT
Rosenthal, S., Bozeman, MT
Sankaran, T., Bangalore, India
Schroeder, D., CIBC, Delemont, Switzerland
soper, R.S., NPS, Beltsville, MD
Spencer, N.R., Sydney, MT
Taylorson, ARS, Beltsville, MD
Tauber, M., Dept. Entomology, Cornell Univ., Ithaca, N.Y.
Tropical Fruit & Vegetable Res. Lab., Honolulu, HI
Turner, C., Albany, CA
Tzanakakis, M.E., University of Thessaloniki, Faculty of Geotechnical Science
and Parasitology, Thessaloniki, Greece
USDA/ARS Laboratory, Columbia, MO
Van Driesche, R., Amherst, MASS
Watson, A., Faculty of Agric., Ste. Anne de Bellevue, Canada
Whitten, M., CSIRO, Australia

Zwolfer, H., Bayreuth, West Germany

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