Group Title: Berry/vegetable times.
Title: Berry/vegetable times. March 2004.
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 Material Information
Title: Berry/vegetable times. March 2004.
Uniform Title: Berry/vegetable times.
Physical Description: Newspaper
Creator: Gulf Coast Research and Education Center, Institute of Food and Agricultural Sciences, University of Florida
Publisher: Gulf Coast Research and Education Center, University of Florida
Gulf Coast Research and Education Center
Publication Date: March 2004
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Bibliographic ID: UF00087388
Volume ID: VID00026
Source Institution: University of Florida
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Berry/Vegetable Times

SEmi AB A Ltir.I &iL

In this issue...
The Effectiveness of Various Page 2
Insecticides to Control Blueberry
Gall Midge
Getting the Most Out of Page 4
Important Considerations for Page 5
Double Cropping
Virus in Yellow Squash in Hills- Page 5
borough County
NASGA Tours GCREC Dover Page 6
New Strawberry Pest Found

GCREC Balm Update Page 7

Chemically Speaking Page 7

Healthy Links Page 7

- --- -- -I RI lI

I (?ifa'ulll e dIIII ,

From Your Extension

The grower meeting held in
February at the Hillsborough Exten-
sion office on peaches, plums and
blueberries had an excellent turnout
and I want to thank the speakers for
a great program and our sponsors for
their support of the meeting. There
is a great deal of interest in alterna-
tive crops from new growers as well
as seasoned growers who are looking
to diversify.
Dr. Jeff Williamson of the
Horticultural Department at UF
spoke on peaches, plums and blue-
berries with low chill requirements
for our area. The peaches and plums
recommended for commercial crops
in this area are the early season fruit
that are smaller than the large fruit
we see in the stores in the summer.
This area has a marketing window to
provide fresh peaches when they are
not available from other parts of the
US. New blueberry varieties were
discussed and Dr. Williamson feels
this area still has the marketing win-
dow from March through April
where we are the only place in the
world to have fresh blueberries. Dr.
Oscar Liburd from the Entomology
Department at UF spoke on scouting
methods for thrips in blueberries and
A monthly newsletter of the University of Florida IFAS,
Gulf Coast Research and Education Center, and Florida
Cooperative Extension Service
Hillsborough County Cooperative Ext Service
5339 CR 579, Seffner, FL 33584
(813) 744-5519 SC 541-5772
Alicia Whdden, Editor Mary Chernesky, Director
Gulf Coast Research and Education Center
13138 Lewis Gallagher Road, Dover, FL 33527
(813) 744-6630 SC 512-1160
Christine Cooley, Layout and Design
Jack Rechcigl, Director
http //gcrec ifas ufl edu

what has given the best control in
trials he has conducted. Dr. Barbara
Smith of the USDA-ARS Lab in
Poplarville, MS spoke on blueberry
diseases in the southeast US and the
symptoms and control measures for
these diseases.
Again thanks to our speak-
ers and to the sponsors- Syngenta,
Dow, BASF and Farm Credit Bu-
reau- for a great meeting!

Alicia Whidden

Summary of New
Insecticides and
Miticides for Florida
James F. Price and Curtis A.

The strawberry industry has
struggled through periods when too
few insecticides and miticides were
available to solve serious production
problems. That is not the case now,
as in recent years several important
new insecticides and miticides have
been registered for use, and more are
During 2003, three new
active ingredients formulated into
four products were approved for
insect and mite control in strawberry.
Additionally, there are seven other
active ingredients that may be regis-
tered in 2004 and the next few years.
This report discusses the three new
products now available to strawberry
(Continued on page 2)

IFAS is an Equal Employment Opportuity Affirmative Action Employer authonzed to provide research, educational information and other services only to individuals and institutions that
function without regard to race, color, sex, age, handicap, or national origin U S Department of Agnculture, Cooperative Extension Service, University of Flonda, IFAS, Florida A & M
University Cooperative Extension Program, and EBoards of the County Commissioners Cooperating

Berry/Vegetable Times

March 2004

t1 .6

Volume IV Issue 3

Berry/Vegetable Times

producers and the active ingredients
that should become available in the
near future.
Products Registered in
2003. Zeal? (etoxazole) is a miti-
cide registered by Valent USA Corp.
in strawberries to control spider
mites, lygus bugs, tarnished plant
bugs and spittlebugs. It acts primar-
ily as an ovicide and larvacide (in
this case, the egg and the first stage
after the mite egg hatches). In this
regard, it performs as a miticide
much like Savey? hexythiazox, al-
though it is currently believed to
possess a unique mode of action and
should not confer cross-resistance
with hexythiazox in spider mites.
Only one application is permitted in
a growing season and it can be ap-
plied within 1 day of harvest. It car-
ries the signal word "Caution".
Admire' (imidacloprid) is
registered by Bayer Crop Science in
strawberries for control of aphids
and whiteflies that affect production
in Florida (there is an additional reg-
istration for perennial strawberries to
control the white grub complex). It
is a systemic insecticide that is ap-
plied to the soil to be moved through
the roots into the leaves. One appli-
cation is permitted in Florida's an-
nual production system, but it must
be applied no later than 2 weeks be-
fore harvest. It carries the signal
word "Caution".
Provado7 (imidacloprid)
also is registered by Bayer Crop Sci-
ences for the control of aphids,
whiteflies, and spittlebugs. This
formulation of imidacloprid is for
foliar application and should not be
used in a season that Admire? was
used. Three applications are permit-
ted but 7 days must elapse between
the last application and harvest.
There are strict precautions neces-
sary to protect honeybees. Provado?
carries the signal word "Caution".
Sluggo? (iron phosphate)
bait is registered by Monterey
Chemical in strawberries for control
of snails and slugs. It carries the
signal word "Caution".

Products Expected in 2004 blueberries had not been correctly

or later. There are several new in-
secticides and miticides expected to
be registered in 2004 and beyond.
These include the miticides: Kane-
mite? acequinocyl by Arvesta Corp.,
Fujimite? fenpyroximate by Nichino
America, Mesa? milbemectin by
Gowan Co., Nexter? pyridaben by
BASF Corp. (is a miticide and insec-
ticide (especially for whiteflies)).
These expected products
also include the insecticides: Knack
7 pyriproxyfen by Valent USA Corp.
(aphids and whiteflies), Intrepid7
methoxyfenozide by Dow Agro-
Sciences lepidopterouss larvae
"worms") andActara7 (foliar) and
Platinum? (soil) thiamethoxam by
Syngenta Crop Protection (aphids,
thrips and whiteflies).
These are the most new
insecticides and miticides to be
available or expected for strawber-
ries in many years. With the proper
use of these products, strawberry
growers should possess the chemical
tools necessary to develop effective
IPM programs for years to come.

(It is the responsibility of the appli-
cation personnel to ensure that all
label directions are understood and

The Effectiveness of
Various Insecticides to
Control Blueberry Gall
Oscar Liburd
Entomology and Nematology De-

The blueberry gall midge
[Cranberry tipworm] Dasineura oxy-
coccana (Johnson) [Fig. 1] is the pri-
mary insect pest infesting rabbiteye
blueberries, Vaccinium ashei Reade,
in the southeastern United States.
Prior to 1992, floral bud abortion
caused by gall midge in rabbiteye

diagnosed, and therefore chemical
control had not been recommended.
Since then, blueberry gall midge
infestations have increased signifi-
cantly, destroying up to 80% of flo-
ral buds on susceptible rabbiteye
cultivars. During 2003, the effec-
tiveness of several insecticides for
controlling blueberry gall midge was
conducted in a heavily infested rab-
biteye planting. The planting was a
4-ha block and contained 'Climax'
and 'Tifblue' cultivars.

Fig. 1. Blueberry gall midge.

Seven insecticides treat-
ments were evaluated including Di-
azinon, at a rate of 1.8 L / ha.
Malathion at a rate of 1.8 L / ha,
Thiamethoxam at a rate of 0.3 L / ha,
Spinosad (SpinTor 2SC) at a rate of
0.4 L / ha (high rate), Azadirachtin
(Ecozin 3% EC, Amvac, Los Ange-
les, CA) at a rate of 0.6 L / ha and
Kaolin clay (Surround WP, Engel-
hard Corporation, Iselin, NJ) at a rate
of 28 kg / ha and an untreated con-
trol block. Insecticides were applied
on 14 and 28 February and 14 March
2003, during stages 2 to 4 of bud
development. All insecticides were
applied using an airblast sprayer.
Insecticide efficacy was evaluated by
randomly selecting 200 floral buds
per insecticide treatment per cultivar
(50 buds per replicate) weekly. Bud
(Continued on page 3)

Volume IV Issue 3

Berry/Vegetable Times



LL 120'

>b b


n '

Diazinon Malathion Thlamethoxam Spinosad

Azadirachtin Kaolin Clay Untreated


Fig. 2. .Effect of selected insecticides on infestation of rabbiteye cv. 'Climax' floral buds by
blueberry gall midge (2003). Means followed by the same letter are not significantly different,
P 0.05, LSD Test.

S 100
S 80 a
C14 ab
W 60- ab

%O 40

-j 20-
C 0


Fig. 3. Effect of selected insecticides on infestation of rabbiteye cv. 'Tifblue' floral
buds by D.. .. I' I. Means followed by the same letter are not significantly
different, P= 0.05, LSD Test.

pressed larval infestation compared
with the control, with the exception
of malathion, which was as effective
as diazinon on the first sampling date
(Table 1 on Page 4). Similar results
were recorded for 'Tifblue' floral
buds, with diazinon significantly
reducing larval infestation compared
with all other insecticide treatments
(Fig. 3). Spinosad, imidacloprid, and
thiamethoxam demonstrated minimal
suppression of blueberry gall midge
though not at the levels needed for
adequate control. Interestingly, kao-
lin clay appeared to increase infesta-
tion of blueberry gall midge. It is
uncertain why this phenomenon oc-
curred although the color of the kao-
lin residues on the buds may have
increased their attractiveness to blue-
berry gall midge. Diazinon was the
most effective compound for control
of blueberry gall midge, followed by
malathion, in both 'Climax' and
'Tifblue' cultivars. Unfortunately,
since these compounds are OPs, their
future use in blueberry programs
may be threatened due to FQPA
regulations. Future studies during
2004 will evaluate the efficacy of
additional reduced-risk insecticides
on gall midge.

samples from the cultivar 'Climax'
were collected on 17 and 23 Febru-
ary and 2 March, for a total of 600
floral buds per insecticide treatment.
Buds from the cultivar 'Tifblue' de-
veloped approximately one week
after 'Climax,' therefore, sampling
was conducted on the same dates (17
and 23 February and 2 March) as
well as 10 March, for a total of 800
floral buds. All bud samples were
transferred to 15-cm plastic petri

dishes containing moistened filter
paper and held at 27C under 14L: 10
D conditions for 10 days to allow
larvae to emerge. The total number
of emergent larvae was recorded.
Results & Discussion. Di-
azinon-treated floral buds had sig-
nificantly fewer blueberry gall midge
larvae compared with buds treated
with other compounds (Fig. 2). Fur-
thermore, none of the other insecti-
cides evaluated significantly sup-

Volume IV Issue 3

Berry/Vegetable Times

Table 1. Effect of selected insecticides on infestation of rabbiteye floral
buds by D. oxycoccana 12I 1 i ).

Mean* number D. oxycoccana

Sampling date

Treatment 17 Feb 23 Feb 2 Mar 10 Mar


Diazinon 2.3a 6.8 4.8a -

Malathion 2.0a 25.3 20.5b -

Thiamethoxam 10.5b 8.3 27.5b -

Spinosad 11.5b 19.5 24.5b -

Azadirachtin 16.3b 30.0 35.5bc -

Kaolin clay 20.0b 47.8 72.0c -

Untreated control 15.5b 15.5 35.3bc -


Diazinon 0.0 2.3 0.8a 10.0

Malathion 0.0 2.0 11.8b 20.0

Thiamethoxam 0.0 2.0 19.8b 29.0

Spinosad 0.3 3.8 18.3b 17.0

Azadirachtin 0.3 5.3 31.3b 20.5

Kaolin clay 0.0 15.8 28.3b 23.3

Untreated control 0.3 13.0 29.3b 17.3

*LS-Means within columns followed by the same letter are not significantly difference, P
0.05 Analysis was performed on square-root transformed data, but means shown reflect un-
transformed data. Treatment effectiveness was evaluated by allowing larvae to emerge from
infested buds.

Getting the Most Out of
Craig Chandler

My wife does most of the
grocery shopping in our family, but
sometimes I accompany her, or I'll
pick up a few things from the super-
market on my way home from work.
I try to make a point of walking

through the produce section to take a
look at the strawberries. This sea-
son, I've been especially interested
in noting the condition of 'Festival'
fruit. Generally its appearance has
been very good. But I have seen
packs containing more than a few
light (orange) colored fruit, indicat-
ing that these particular fruit were
harvested at less than optimum ripe-
ness. These fruit tend to be overly

firm and lack the sweetness that
would come with another day or two
on the bush. This is unfortunate be-
cause I think 'Festival' has the inher-
ent firmness and skin toughness that
allows it to be harvested at optimum
eating quality and still be resistant to
bruising. (Harvesting only fruit that
are at optimum ripeness, however,
may not be practical when daytime
temperatures are in the 80s and
nighttime temperatures are in the
60s. Fruit tends to ripen more
quickly under these conditions, and
light colored fruit left on the bush
may be over-ripe by the next pick-
'Festival' fruit typically
turn an orangish-red before mellow-
ing into a deep red. It is this deep
red (on all sides of the fruit) that
indicates the fruit has reached opti-
mum ripeness. Sometimes the top-
side of the fruit will become deep red
before the bottom side (or the side
touching the plastic). Harvesting
only fruit that are at optimum ripe-
ness would require careful observa-
tion by the pickers. If they have any
doubt as to a fruit's ripeness, they
should turn the fruit to inspect its
backside -- before removing it from
the plant. Careful observation can
also spot fruit that have small sap
beetle holes in them, or Botrytis in-
fections that are partially or wholly
hidden by the calyxes fruit that
may look perfectly fine to a frenzied
picker. This level of observation
requires the picker to move more
slowly, resulting in fewer trays har-
vested per picker. This, of course,
would increase the cost of harvest, as
pickers would have to be compen-
sated for their extra diligence. But it
would result in a superior product,
and hopefully greater customer satis-
faction and demand.

(Continued on page 5)

Volume IV Issue 3

Berry/Vegetable Times

Important Virus in Yellow Squash
Considerations for in Hillsborough County
Double Cropping Alicia Whidden Hillsborough Co.
John R. Duval ext. agent II & Susan Webb -
assoc. professor., Entomology.
The time has come once and Nematology. Dept.
Vegetarian 01-04
again to turn part of our attention Vegetarian 01-04
away from the production of straw-
berry and on to other crops. Inter- In October 2003 in Hills-
borough County, a field of 'Gentry'
planting secondary crops (cucurbits orouh ouny a el o e
and peppers) among existing straw- yellow crookneck squash was se-
berries is a great means of getting the verely affected by the watermelon
So o p i strain of papaya ringspot virus
most out of fumigation, plastic
mulch, and drip tubing. Certain (PRSV-W) (Fig. 1), formerly called
management practices must be WMV-1. PRSV-W infects cucurbits
almost exclusively but does not in-
adopted to allow for the simultane- almost exclusively but does not in-
ous growing of these crops in the fect papaya. It is the most important
field. First and foremost is proper of the aphid-transmitted viruses af-
pre. fecting cantaloupe, watermelon, and
pesticide selection for controlling
insects and diseases. Pesticides such squash in central and south Florida.
as Switch and Topsin Mcannot be The virus is spread in a nonpersistent
applied to strawberries when other manner by over 20 species of aphids.
applied to strawberries when other
crops are present in the field due to Aphids do not retain the virus for
labeling restriction on the second very long but can acquire and trans-
mit it in very brief probes of the leaf
crop. Labels for all pesticides should it in very brief probes of the leaf
be read carefully to ensure that they surface.
can be used on both crops. Sec- Both folage and fruit
only, fertilization needs to be symptoms observed in 'Gentry' were
slightly increased to meet the needs severe. The leaves of the plants were
of both crops. Strawberries, since distorted and mottled, with the newer
of both crops. Strawberries, since
Leaves reduced in size and very nar-
they are well established, will be
able to out compete the secondary row laciniatee or filiform). The
crop for nutrients. However, an in- squash were knobby instead of
crease in fertilization of 10-15% smooth with green veining over the
should supply enough material for fruit. Yield was greatly reduced. In
established strawberries and young this field, you could see where the
establishing ccurbits and peppers virus had first infected squash on the
establishing cucurbits and peppers. .
north side where an old abandoned
Lastly, once strawberries are no north sde where an old abandoned
longer being harvested the bushes orange grove overgrown with weeds
d be r d f t t o was present. It was easy to tell that
should be removed from the top of
the bed. Excessive vegetation can the plants next to the grove had been
infected at an early age. By the time
reduce the quality of secondary cropsfected at an ear a B the tme
of harvesting, the plants on this side
(such as when a cantaloupe rests on a of harvesting, the plants on this side
rotting strawberry plant), interfere of the field were severely stunted
with application of spray materials, and were distorted with little to no
and harbor insects and diseases. fruit. The fruits present were small
and harbor insects and diseases.
Making a few simple management and gnarled with much green vein-
decisions can help guarantee a suc- ing. The spread of the virus through
Sl s b the field appeared to follow the pre-
cessful late season berry crop and
secondary crop and increase mone- vailing wids. As you moved south
tary returns to the farm. across the field away from the grove,
symptoms were milder. More distant
plants had normal lower leaves and
fruit with only the upper portion of
the plants and youngest fruit dis-

torted, indicating that these plants
had been infected later than plants
near the grove.
The grower noticed no
aphids on the plants but it is unlikely
that he would have noticed transient
winged aphids without using yellow

Fig. 1. PRSV-W symptoms in squash. Photo
credit: Gary Simonne.

Fig. 2. Balsam apple growing on a ditch bank
in southwest Florida. Photo credit: Warren

(Continued on page 6)

Volume IV Issue 3

Berry/Vegetable Times

sticky traps or yellow pan traps to
monitor their presence. To transmit
the virus, the aphid does not have to
be settling down to feed on the
squash but can be merely probing the
surface of the leaf to determine if the
plant is a suitable host. In the proc-
ess, it can acquire virus from an in-
fected squash plant and move it to
another or transmit a virus that it
may have already acquired. Most
insecticides do not act quickly
enough to prevent transmission.
Many of the aphid vectors are tran-
sients coming from weeds and do not
reproduce on cucurbits. Melon
aphid, which does reproduce on
squash, can transmit the virus but
may not be an important vector be-
cause it does not move as readily as
aphids looking for other host plants.
Samples were collected from the
field and tested by ELISA for nine
viruses known to infect cucurbits. Of
39 samples, 38 were positive for
PSRV-W. The sample not infected
with PRSV-W had severe viral
symptoms. We were able to repro-
duce the symptoms by rubbing the
sap from the ground sample onto
squash seedlings in the greenhouse.
Further tests are being done to deter-
mine what this virus might be. Nine
samples of the predominant weed in
the abandoned grove, balsam apple,
(Momordica charantia), were also
tested (Fig. 2). The vines of this
weed almost covered some of the old
trees. All of balsam apple samples
were positive for PRSV-W, although
no sample had obvious symptoms.
This weed and another, creeping
cucumber (Melothria pendula), have
been shown in the past to be impor-
tant sources of PRSV-W.
The grower also had three
varieties of zucchini squash
('Dividend', 'Cash Flow', and
'Payroll') growing just east of the
block of yellow squash. The zucchini
did very well all season. Only at the
very end of the season were mild
virus symptoms seen on 'Dividend'
and 'Cash Flow'. None was seen on
'Payroll'. According to Rogers

(Syngenta Seeds), 'Payroll' has tol-
erance to zucchini yellow mosaic
virus (ZYMV) and watermelon mo-
saic virus (WMV-2) (also found in
Florida), 'Dividend' has tolerance to
these two viruses and cucumber mo-
saic virus (CMV), and 'Cash Flow'
has tolerance to ZYMV. No claim is
made for tolerance to PRSV-W, al-
though in this case it appears that
these varieties may not develop se-
vere symptoms when infected. How-
ever, no samples of the zucchini va-
rieties were tested.

Christine Cooley

Gulf Coast Research and
Education Center hosted a tour for
the North American Strawberry
Growers Association on what had to
be one of the most beautiful days of
this past February. Nearly 200 par-
ticipants came to the center to learn
about strawberry production and the
research taking place at GCREC.
Each of the center's faculty as well
as faculty from Gainesville, Braden-
ton and Lake Alfred participated in
the event. Brief program presenta-
tions, an exhibit area and bedding
demonstration gave the NASGA
group insight on Florida strawberry
production. For lunch, the group
was treated to a wild game cookout
including swamp cabbage, wild boar,
turkey, and alligator, and entertain-
ment was provided by Billy and the
Boys, a local bluegrass band. How-
ever, the highlight for most of the
visitors was the alligator wrestling
demonstration from Gatorland.
Thanks to everyone who participated
and to NASGA for the opportunity
to showcase the center and the re-
search provided to the local straw-
berry industry.

A beautiful, warm Florida day provided the
perfect backdrop for the NASGA tour at
GCREC Dover.

The bedding equipment and demonstration
was organized by BBI Produce, Inc.

Gatorland wrestlers entertained and
educated the NASGA group, most of
whom had never seen a live alligator.

Even UF employees, like Joanie Souder,
were able to interact with some of
Florida's wildlife .

Volume IV Issue 3

Berry/Vegetable Times

New Strawberry Pest
James Price

On 5 March 2004, staff at
GCREC Dover discovered a few
locations on the farm where about a
half dozen mature strawberry plants
were wilting and dying. Their in-
vestigations revealed a 3% inch white
grub weevil larva on or in the root
crown. All white roots had been
severed. The preliminary identifica-
tion is Diaprepes root weevil, known
in the area for problems in citrus and
ornamental nurseries. Please report
any discoveries of this new problem
in area strawberry to Hillsborough
Co. vegetables/strawberry extension
agent Alicia Whidden (813) 744-
5519 ext. 134 or strawberry ento-
mologist Jim Price (941) 751-7636
ext. 246.

GCREC Balm Update
Christine Cooley

Work continues at the new
research center that will house both
Dover and Bradenton faculty and
staff in early 2005. Now that the
property has been cleared of hun-
dreds of citrus trees, the infrastruc-
ture and building foundations are
being constructed. The photos be-
low show the progress taking place.
The center is slated to be a state-of-
the-art research center and the pride

Building foundations are being completed.

of UF/IFAS. Updates on the con-
struction can be found on the
GCREC website http://

navy cquipmltcI is1 a suic sigl ui cosulsiuc-
tion in Balm.

Chemically Speaking
February 2004

Based on a request by IR-
4, time-limited tolerances have been
established for residues of the fungi-
cide cyprodinil in strawberry and
onion (dry bulb or green). The toler-
ances expire on 12/31/04. (Federal
Register, 12/31/03.)

UF Biotech Affiliated
Company to Produce Biological
Nematicide. Pasteuria Bioscience,
located at UF's Biotechnology De-
velopment Institute in Alachua is
beginning to gear up for commercial
production of the bacterium Pas-
teuris penetrans, a known nematode
control agent. Two venture capital
companies have recently invested
$750,000 into the company, which
has developed a method to mass rear
the organism and make it affordable
on a farm scale.
With the imminent loss of
materials such as methyl bromide
and fenamiphoas (1 c!,. i. .I! .), the
market for new nematicides is large,
as these pest annually cause an esti-
mated $100 billion in damage. The
investors believe the market may
well be worth hundreds of millions
of dollars each year. The company
plans to begin field testing of the
produce this spring, beginning with

micro -plot trials on crops such as
tomato, peanut, and cucumber. (The
High Springs Herald, 1/1/04.)

Health and Nutrition
Related Links

To learn more about health
and nutrition, including the nutri-
tional benefits of berries, visit the
following sites:

American Dietetic Association
www. eatright. org/Public

Produce For Better Health Founda-

Sports, Cardiovascular and Wellness

United States Department of Food
and Agriculture

United States National Agricultural

Vegetarian Diets

State of Michigan Dept. of Agricul-
www.michigan. gov/mda/0%

US Highbush Blueberry Council


Food Hbc/Berries Hbc.htm

Volume IV Issue 3

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