Title: Berry/vegetable times
Full Citation
Permanent Link: http://ufdc.ufl.edu/UF00087388/00063
 Material Information
Title: Berry/vegetable times
Physical Description: Serial
Language: English
Creator: Gulf Coast Research and Education Center, Institute of Food and Agricultural Sciences
Publisher: Gulf Coast Research and Education Center
Place of Publication: Gainesville, Fla.
Publication Date: September 2009
 Record Information
Bibliographic ID: UF00087388
Volume ID: VID00063
Source Institution: University of Florida
Holding Location: University of Florida
Rights Management: All rights reserved by the source institution and holding location.


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SBerry/Vegetable Times

September 2009

Calendar of Events

Sept. 15 & Oct. 13, 2009
Pesticide License Testing.
Hillsborough County
Extension Office, Seffner. 9
am. For more information call
Mary Beth Henry at 813-744-
5519 ext. 103.


October 28, 2009
Free Registration at
Sessions on
Vegetables, Strawberries
Blueberries, Blackberries
and Peaches
Sustainable Water Use
Methyl Bromide Updates
Field Tours

A University of Florida/IFAS and Florida
Cooperative Extension Service
Hillsborough County, 5339 CR 579
Seffner, FL 33584 (813) 744-5519
Joe Pergola, County Extension Director
Alicia Whidden, Editor
Gulf Coast Research & Education Center
14625 County Road 672,
Wimauma, FL 33598 (813) 634-0000
Jack Rechcigl, Center Director
Christine Cooley, Layout and Design
James F. Price, Co-Editor

From/ Your A g-e-t
Renewing Your Pesticide License With FDACS

Growers who have had to renew their Private
Applicator Restricted Pesticide License recently have found
that they had a very long wait to receive their new license.
After talking with the FDACS Bureau of Compliance
Monitoring which handles your license renewals, I found that
due to budget cuts their department has taken from the state
that they are short staffed and things are taking longer to get
done. First your renewal goes to a finance department that
processes your payment and that is taking at least a week
longer and then it goes to the person that checks your
paperwork and issues the new license and they tell me they
are taking about a week longer than in the past. With all the
delays in processing you could find your operation without a
(Continued on page 2)

New Spotted Wing Drosophila to Attack Florida
James F. Price and Curtis Nagle

A new pest has arrived in Hillsborough Co. that could
affect production of strawberry, blueberry, raspberry and
other thin, soft-skinned fruit. In August, 2009, the spotted
wing drosophila (SWD) (Drosophila suzukii (Matsumura),
Diptera:Drosophilidae) was discovered in the northeast corner
of the county after having been known about 1 year in
California and for less time in Washington.
This fly, originating in the Orient, appears very much
like the common drosophila flies that accumulate on over-ripe
bananas, flats of strawberries left without refrigeration, old
fallen citrus, and other fruit beginning to spoil. In fact, both
are small, have prominent red eyes and, indeed, are closely
related. Wing tips of SWD males have a dark spot that is
lacking in our common drosophila (Fig. 1).
(Continued on page 2)

IFAS is an Equal Employment OpportuntyAffirmative Action Employer authorized to provide research, educational formation and other services only to individuals and institutions that
function without regard to race, color, sex, age, handicap, or national orgin U S Department ofAgriculture, Cooperative Extension Service, Umversity of Flonda, IFAS, Florida A & M
Umnversity Cooperative Extension Program, and Boards of the County Commissioners Cooperating

(Continued from page 1)
license during a critical time in your
production season.
To try to prevent a delay in receiving
your license renewal, here are some things I
would advise you to do. When you receive
your license renewal in the mail, which
typically comes 6-8 weeks before your
license will expire, have your paperwork
ready and send it in right away. The longer
you wait the greater the chance you will not
get your renewal back before the expiration
date. Know your renewal date and be sure
you have the continuing education units
(CEUs) you need for renewal before you get
your renewal notice. For a Private Applicator
license you need 4 Private Applicator CEUs
and 4 CORE CEUs for every 4 year renewal
cycle. Do not wait until the renewal notice
comes in to try to find all your credits. Call
me early and we can start working on the
credits so you can have them by the time you
receive your renewal notice. Fill out your
renewal paperwork and don't forget to
include the check for the renewal fee. Be
sure on your CEU paperwork that you have
filled in the top part of the paperwork with
your information and be sure to sign the
CEU form. Also be sure you mail in the
correct number of CEUs for each category.
You can always have more but you must
have at least 4 for each category. If you have
any questions give me a call.
Here's hoping we have good weather
for the start of the season,
AllCoiW/ Whid-dev
813-744-5519 ext. 134

(Continued from page 1)

Female SWD possess serrations on their egg
laying organ that can cut soft surfaces of
sound fruit to lay eggs inside. Common
drosophilid flies are without that modified

Fig. 1. Male spotted wing drosophila. Photo courtesy
of G. Arakelian, Los Angeles County Agricultural
Commissioner/Weights & Measures Department.

ovipositor. SWD eggs that hatch inside fruit
become white maggots that can soften and ruin
fruit in the field or can accompany harvested
fruit undiscovered until the fruit are in
consumers' hands. There presently are no
restrictions to be placed on fruit from infested
This group of small flies often is called
the pomace flies, vinegar flies, or the fruit
flies, but use of "fruit flies" in this case is
confusing since that common name applies to
larger flies, the Tephritidae, often problematic
and reported in the news media. Tephritids
include banded winged flies of concern such as
Mediterranean fruit fly, Caribbean fruit fly,
Oriental fruit fly, Mexican fruit fly, and others.
Drosophilid flies are not closely related to
tephritid flies and management of the two
groups can be vastly different. For instance,
rare outbreaks of Mediterranean fruit fly in
Florida are managed in part with mass releases
of sterilized male Mediterranean fruit flies.
This technique has not been developed for
drosophilids and is impractical to consider in
most cases.
The SWD is expected to survive well in
Florida's climate and, given the swift
(Continued on page 3)

'~> KS

P-ot I -

(Continuedfrom page 2)
colonization of California, strawberry
growers should expect to encounter this fly
in winter 2010 and beyond. The degree of
interference to production is clearly
unknown. However, management plans are
surfacing. Below are tactics that can be
applied as conditions warrant. Presently
there are no action thresholds established or
even farm-level scouting protocols
established. Presence of SWD on a farm
could be ascertained by sweep-netting and
observing Drosophila spp. attracted to
strategically placed bait containers of rotting
fruit or of bait prepared from aged bananas
mixed with a package of yeast activated by
warm water.
Management practices immediately
available in Florida for SWD are those used
to manage our common drosophilids.
Additional techniques of adapting tephritid
fruit fly baits with toxicants are being
considered and developed for strawberries,
but some problems exist in transferring the
procedure to the SWD/strawberry system.
The most important progress in
managing this new pest will be achieved by
implementing cultural practices that deny
SWD its breeding sites and kill immature
SWD inside infested fruit. This can be
achieved in a strawberry field by removing
marketable berries quickly, before they are
infested, and removing and properly
disposing unmarketable fruit and the
immature insects they may harbor.
Strawberry fruit disposal should go
beyond the common practice of dropping
unsalable fruit into the row middle. Any
fruit not to be sold should be collected and
buried or collected, covered, and sent to
municipal disposal sites.
Additionally, applications of
appropriate insecticides should be made as
SWD appear. Insecticides presently
approved for Drosophila spp. fly control
include malathion, diazinon, and pyrethrum

based products (Table 1/Page 4) targeted to
adults. There are no insecticides available for
maggot control inside fruit. It is unknown how
long residues of malathion or diazinon could
be effective to kill SWD flies, but the effective
period of pyrethrum is very short.
Consequently, repeated applications at close
intervals may be required under heavy
pressure, for populations of mixed life stages,
or when flies move from outside sources into
fruiting fields. When these conditions do not
exist, applications perhaps could be held to one
lifecycle or longer, probably 10 days to 2
weeks or longer during much of Florida's fruit
production period.
A component oftephritid management
often includes large droplet applications of
protein-based bait such as Nulure mixed with
an insecticide or GF-120 bait manufactured
with spinosad insecticide. It is uncertain if
such tools can be effective for SWD under any
circumstances. However, it is known that
problems maintaining adequate moisture level
will exist in the bait residues used in a SWD/
strawberry system. And it may be problematic
to deliver sufficient quantities of effective bait
and toxicant mixture in an environment of
heavy feeding pressure by common
drosophilid flies.
Production by vigilant and responsive
strawberry growers in Florida probably will
not be reduced by this new pest, so long as the
present management tools remain effective and
available and growers cooperate to manage
SWD throughout the area. New management
measures must be developed, though, to assure
long-term control and to reduce the impacts
that presently available insecticides can have
on Orius spp., Phytoseiuluspersimilis, and
other naturally occurring or applied beneficial
useful in Florida strawberry production.

(Continued on page 4)

(Continued from page 3)
Sources andAdditional Information

Bolda, M. 2008. New fruit fly pest in strawberries and caneberries. University of California, Agriculture and
Natural Resources Blogs, Strawberries and Caneberries, 21 November 2008 http://ucanr.org/blogs/blogcore/
postdetail.cfm?postnum=821), viewed 1 Sep 2009.

Bolda, M. 2009. Update on the cherry vinegar fly, Drosophila suzukii, now known as the spotted wing Drosophila.
University of California, Agriculture and Natural Resources Blogs, Strawberries and Caneberries, July 9,
2009, http://ucanr.org/blogs/blogcore/postdetail.cfm?postnum=1483, viewed 1 Sep 2009.

Bolda, M. 2009. Drosophila suzukii update. University of California, Agriculture and Natural Resources Blogs,
Strawberries and Caneberries, June 3, 2009. http://ucanr.org/blogs/blogcore/postdetail.cfm?postnum=1351,
viewed 1 Sep 2009.

Cline, H. 2009. CVF causing widespread damage. Western Farm Press, 6 July 2009, http://westerfarmpress.com/
citrus/cherry-fruit-fly-0706/), viewed 24 July 2009

Delfinado, M. D. & D. E. Hardy. 1977. A catalog of the Diptera of the oriental region. Vol III Suborder
Cyclorrhapha. The University Press of Hawaii, Honolulu. x + 854 pp

Kaneshiro, K. Y. 1983. Drosophila (Sophophora) suzukii (Matsumura). Proceedings Hawaiian Entomological
Society 24: 179.

Kanzawa, T.1936. Studies on Drosophila suzukii Mats. Journal of Plant Protection (Tokyo) 23: 66-70. 127-132,
183-191. Abstract in Review of Applied Entomology 24: 315.

Kanzawa, T.1939. Studies on Drosophila suzukii Mats. Kofu, Yamanashi Agric. Exp. Sta. 49 pp. Abstract in
Review of Applied Entomology 29: 622.

Steck, G.J., W. Dixon, & D. Dean. 2009. Spotted wing drosophila, Drosophila suzukii (Matsumura) (Diptera:
Drosophilidae), a fruit pest new to North America. Pest Alert. Florida Dept. Agric. and Consumer
Services, Div. of Plant Industry. hulp \\1\\ fl-dpi.com/enpp/ento/drosophila suzukii.html#pagecontent,
viewed 1 Sep 2009.

Uchino, K. 2005. Distribution and seasonal occurrence of cherry Drosophila, Drosophila suzukii (Diptera:
Drosophilidae), injurious to blueberry in Chiba Prefecture. Annual report of the Kanto Tosan Plant
Protection Society 52: 95-97.

University of California Cooperative Extension, Mariposa County. Be on the look out for spotted wing
Drosophila.http://cemariposa.ucdavis.edu/files/67726.pdf, viewed 1 Sep 2009.

van der Linde, Kim. 2009. Zaprionus indianus distribution in the United States. hip \\ \\\ kIuvdlinde.com/
professional/Zaprionus%20distribution%20US.html, viewed on 1 Sep 2009.

Table 1. Insecticides available in Florida for management of Drosophila spp. flies on strawberries.
Active Ingredient Common Name REI PHI Mode of Action Code
Malathion Malathion 12 hours 3 days 1B
Diazinon Diazinon 24 hours 5 days 1B
Pyrethrum Pyganic 12 hours 0 days 3
Pyrethrum with Piperonyl butoxide Pyrenone 12 hours 0 days 3

The New Kid on the
Breeding Block.
Vance M. Whitaker

A couple of weeks
ago at the Agritech
meeting, Dr. Craig
Chandler announced that
he has been experimenting with cloning
technology. Instead of hiring a new breeder,
he instead decided to clone himself. To
prove it he showed a current picture of me
alongside a picture of himself as a PhD
graduate. Even I had to admit that our
pictures looked alike. I also have to admit
that getting a clone of Craig Chandler must
be quite tempting considering his success in
generating great cultivars for Florida
strawberry production. His varieties,
particularly 'Festival' and now 'Radiance',
have been great steps forward, and he has
more promising selections coming through
the pipeline.
In reality we are different people,
beginning with our backgrounds. I grew up
in the small town of Oak Ridge, NC amidst
rolling hills and tobacco fields. I cultivated a
love for plants and eventually went to North
Carolina State University to study
horticulture. I later pursued my graduate
studies at the University of Minnesota. My
wife Terri and I started our family there, and
I am blessed to have Isaac (3.5 yrs) and
Claire (1.5 yrs). Aside from learning
important things in Minnesota like how to
live in 30 below zero temperatures without
dying of frostbite and drive in a blizzard, I
really enjoyed fishing in the summers and
took several trips to the Canadian border.
Needless to say, I'm looking forward to
Florida fishing, and I won't be missing the
Minnesota winter!
During my first year I will be
learning the breeding process at Craig's
elbow. I'm grateful he's staying this season
to ease the transition. I would also like to

enlist your help as I learn how you grow
strawberries. I plan to visit as many of you as I
can, and I would also like to extend an open
invitation to the growers to visit the GCREC at
any time. I plan to learn a lot as I observe your
operations, and I welcome your input and
All of you should know from the start
that I am committed to continuing Craig's
progress in developing Florida varieties. We
have a great team of researchers working on
strawberry at the University of Florida.
Together, I believe we can make continued
progress using all the tools at our disposal,
including traditional breeding and new
technologies. I'm excited for what the future

Fighting Phytophthora Crown Rot
Jim Mertely and Natalia Peres, Sept 2009

Crown rot diseases often start early in
the season, and may kill strawberry plants even
before they begin to produce. Crown rots are
caused by different fungi including
Colletotrichum (the cause of anthracnose
crown rots), Macrophomina (charcoal rot), and
Phytophthora (Phytophthora crown rot).
Colletotrichum spp. have been responsible for
the majority of plant losses in our area.
However, Phytophthora crown rots are gaining
in importance and deserve more attention.
P. cactorum has been identified as the
main cause of Phytophthora crown rot in
Florida. Other species may also be involved,
but in general, all the Phytophthora produce
similar reddish brown infected areas inside
diseased crowns (Fig. 1). Once the crown is
sufficiently damaged, which may take a few
days to a few weeks, the top wilts and dies
(Fig. 2). Phytophthora species are commonly
called water molds, but actually are more
closely elated to brown algae than to the fungi.
They produce several types of spores, the most
(Continued on page 6)

(Continued from page 5)
interesting of which is the zoospore.
Zoospores have tiny flagella that allow them
to swim in water films on the plant surface
and in the soil water matrix. For this reason,
infection is more likely to occur under wet
conditions, in low spots, or in poorly drained
soils. These conditions may occur in the

Fig. 1. Internal crown rot symptoms.

Fig. 2. Plant collapse due to crown rot.

nurseries resulting in infected transplants that
are eventually set in Florida fields.
Visual examination of the transplants
is not a practical way to determine if
Phytophthora is present. Waiting until many
plants show symptoms in the field is also a
poor option, particularly for susceptible
cultivars. Based on our general observations,
the Florida cultivars Carmine, Sweet Charlie,

Florida Radiance, and Winter Dawn are highly
susceptible to Phytophthora crown rot, while
Florida Festival is more resistant. Florida-
grown cultivars will be tested for susceptibility
to Phytophthora crown rot in a variety trial at
the Gulf Coast Research and Education Center
(GCREC) this fall. Similar trials in California
have shown that Catalina, Diamante, and
Ventana are susceptible while Aromas,
Camarosa, and Camino Real are moderately to
highly resistant.
To control Phytophthora in highly
susceptible cultivars, growers should consider
a preventative program. Two different
chemistries are available for this use. One is
mefenoxam (metalaxyl), the active ingredient
in Ridomil Gold and Metastar. These products
are injected through the drip tape and are
highly effective against Phytophthora diseases
in many crops. In strawberries, they have also
been used curatively, i.e, after the first diseased
plants are observed in the field. A serious
drawback is that one application costs from
$50 to $100 per acre, and two applications may
be needed to treat a seriously diseased crop.
Products containing potassium phosphite or
potassium salts of phosphorus acid are less
expensive alternatives. This group includes
the phosphite fungicides Fosphite, Fungi-Phite,
Helena Prophyt, K-Phite, Phostrol, and Topaz
and the related aluminum derivatives Aliette,
Legion, and Linebacker. Phosphites and their
derivatives are generally applied as foliar
sprays, although some are also labeled for drip
application. Members of this group are not
curative, and multiple applications are needed
beginning immediately after the plants are
watered in. The effectiveness of a combined
program consisting of a single curative
application of Ridomil Gold or Metastar
followed by foliar applications of a phosphite
needs to be investigated.
Biological products such as Actinovate
and Rhapsody are also labeled for the control
of Phytophthora crown rot in strawberries.
(Continued on page 7)

(Continuedfrom page 6)
Similar products may become available over
the next few years. Research is needed to
determine whether these products provide an
acceptable level of control under Florida
Growers of Phytophthora-resistant
cultivars may also see plants collapse and die
early in the season. Although Phytophthora
crown rot could be involved, the true culprit
may be another crown or root rot pathogen.
In these cases, we strongly recommend
submitting a sample to the UF Plant
Diagnostic Lab at GCREC. There, the
pathogen will be isolated and identified, and
control recommendations will be provided,
usually within 3 to 5 days. A good sample
consists of 5 to 6 plants in early stages of
collapse or decline with their roots still
intact. Place the plants in a plastic bag to
keep the roots from drying out but do not add
extra water to the bag. Any questions
concerning samples and sampling can be
directed to Dr. Jim Mertely at (813) 633-
4131 (0) or (813) 434-7543 (cell).
Remember that the GCREC Plant Diagnostic
Lab is now charging a fee. Checks for $40
should be made to the University of Florida.

Notes on Cultural Practices
Considering Including Sulfur as
Part of the Fertilization Program for
Bielinski M. Santos

Sulfur (S) is a structural component
of the essential amino acids methionine and
cysteine, which are building blocks for many
proteins in plants. However, fertilization
programs for vegetable and small fruit crops
have traditionally focused on the application
of other elements (e.g. nitrogen, phosphorus
and potassium). There were two main
reasons why little attention has been paid to
S fertilization. First, S was a common

component of widely used fertilizers, such as
triple super phosphate and ammonium sulfate.
Second, there were significant atmospheric
inputs from acid rain generated from burning S
-loaded fossil fuels used in industries and by
motor vehicles. Nevertheless, this situation has
dramatically changed during the last decade.
Granular and liquid fertilizers no longer rely
heavily on sulfates, and stringent federal and
state environmental regulations have reduced
the incidence of acid rain. Therefore, S
deficiencies are likely to occur.
In most crops, typical S deficiencies are
generalized leaf yellowing or light green
foliage with weak plant vigor. These
symptoms are very similar to those caused by
the lack of other major nutrients, particularly
nitrogen. This frequently confounds the ability
of growers, researchers and extensionists to
diagnose S deficiencies correctly. Deep sandy
soils in west central and southwest Florida
have modest organic matter content, reducing
the capacity for S retention. Thus S leaching is
likely to occur before root absorption takes
Research conducted at the GCREC has
shown significant strawberry yield responses
(up to 11%) to S fertilizers. There are a variety
of S-containing fertilizers in today's market:
Ammonium sulfate (21% N, 24% S), sulfate of
potash (42% K, 18% S), liquid calcium
thiosulfate (10% S), and elemental S (90% S),
among others. In the case of the latter,
microbes in the soil convert the elemental S to
the sulfate ion, which is what plants absorb.
This S source is widely used to lower pH
because it generates acidity in the soil. If a
grower has applied elemental S in the
strawberry field during the last year, probably
the S levels in the soil are sufficient for
satisfactory crop growth. Conversely, using
certain drip line cleaners, such as diluted
sulfuric acid, indirectly provide S to the crop.
In any case, having a S source either
preplant granular (elemental S or a sulfate-
(Continued on page 8)

(Continuedfrom page 7)
based fertilizer) or as a drip-applied
formulation (calcium, potassium or
magnesium thiosulfates) will provide the S
strawberry needs for quick establishment and
flowering. It has been determined that a S
rate between 25 and 50 lb/acre may suffice
the crop. Also, it appears that there is little
difference among sources (i.e. granular and
liquid), as long as the nutrient is present and
available in the soil during root development
and first flowering. It is recommended to
perform at least one foliar nutrient test during
the season to check the status of this
nutrient, which should be from 0.3 to 0.5% in
the upper mature leaves during mid-

Methyl Bromide Transition
Strategy: A Fall 2009 Focus on
Drip Fumigation under Old and
New Plastic
J.W. Noling and Alicia Whidden

The fumigation season in the Plant
City area started in mid August, and in a
timeframe much earlier than usual in our
opinion. In previous years, the fumigation
season has always seemed to begin in a mad
dash just after Labor Day. In driving around
the area, there also appears to be about 30%
less new plastic being laid this fall than there
was last fall. In these fields of 'old, twice-
used' plastic, growers are planning to double
crop 10, 20 and even 30 acre fields with a
second crop of strawberries. We have to
confess, some of these fields are overgrown
with weeds in the middles and plant holes,
while in other fields the low cost 1 mil
plastic from the previous season is brittle and
zippering easily under pressure. We have to
believe that these fields may produce some
disappointing results for double cropped
The primary appeal in double

cropping berries after berries is to save money.
Other growers trialing the double crop concept
are not quite sure how much money is actually
being saved when actual field and plastic
maintenance and herbiciding costs are factored
into overall production costs. We are of the
opinion that there was a lot of berries produced
last year but many growers didn't get the
prices needed to make it a truly profitable
cropping season. The decreased supply of
methyl bromide with possibility of shortages,
coupled with the increased price of $5.70 / lb
for a formulation of 50% methyl bromide and
50% chloropicrin (which most growers don't
seem to care for in first place) also has
encouraged growers to try something different
and economical. Finally, there were the
observations and testimonials from a few of
the double cropping pioneers in the industry
which made a huge difference in comfort level
and attitude about trying something new.
For double cropped strawberry with an
existing bed and plastic mulch cover, the
choice for method of fumigant application
becomes very simplified. Only a drip, rather
than chisel applied fumigant, can be used for
bed treatment. One of the reasons why
bedding may have started earlier this year
might be because many growers after bedding,
will put out a drip fumigant and will need the
extra time to establish the irrigation and wait
for the fumigant to dissipate. So it seems that
there will be a considerable amount of drip
fumigation going on this season under both old
and new plastic. Maybe as much as about 40%
of the acreage.
As we reported at AgriTech, there is
also a lot of drip fumigation going on in
California strawberry as well. This past year,
55% of the 37,000 acres of California
strawberry were using Telone Inline, and to
some extent Chloropicrin EC to replace methyl
bromide soil fumigation. Vapam HL was also
often used in sequential combination, being
applied 7 days after InLine or Chloropicrin EC,
(Continued on page 9)

(Continued from page 8)
for weed control. With high levels of
production and pest control efficacy
maintained, California has set an
encouraging precedent for drip applications
of the soil fumigants as effective alternatives
to methyl bromide and chloropicrin soil
fumigation for strawberries.
In our last newsletter we expressed
concern about the reliance on drip fumigants
like Vapam and K-PAM for crop termination
and as preplant treatments for the fall double
crop of strawberry. We really didn't like the
idea of 'bettin the farm' on a new, largely
untested, production practice. Our concerns
were based on likely application procedures
which would include Mazzei injectors
(which can seriously rob pressure and emitter
flow) and injection schedules which were not
long enough or of suitable chemical
In general, our concerns were based
on applications where these products would
be applied too quickly, producing a series of
circular wetted zones (spots) or only in a
relatively narrow strip down the middle of
the bed with little or only limited gas phase
movement into the shoulders. We
rationalized that this would likely leave a
relatively high level of surviving nematodes
in the shoulders of the bed which could
remain or migrate into deeper soil only to
return after planting.
We were also aware however that a
full summer of solar heating of a black
plastic covered bed might provide an
appreciable level of thermal control of the
nematode. In May, we placed a number of
recording temperature sensors at 5 and 12
inch soil depths on both the east and west
bed shoulders and at the bed center. We
were pleasantly surprised to discover how
temperatures could cycle between 85 and
118 F on a daily basis for the duration of the
summer for all bed shoulder locations and to
a somewhat lesser degree even in the bed

middle (Fig. 2). Sting nematode has well
defined optimal temperatures for growth,
development, and reproduction and these are
all typically defined in the range of 75 to 900 F
at most.
In the absence of food, lipid reserves
are burned faster at higher temperature, and
nematodes which do not die from temperature
induced heat stress, are more than likely to die
from starvation. So, it would seem that maybe
the drip treatment for a double cropped bed
doesn't need to be perfect if the fields are
maintained weed free and the beds are allowed
to bake in the sun all summer long. Given the
number of fields trialing double cropping, we
shall soon be able to see whether the
performance of the drip applied fumigants was
complemented by these daily acts of mother
What are the drip fumigants that are
going to be used in Florida strawberry this
season? Nothing new there, they will include
Vapam HL (75 gpa), K-PAM HL (60 gpa),
Telone EC (12 gpa), Telone Inline (35 gpa),
Chloropicrin EC (200 lb/a), or Pic Clor 60 EC
(300 lb/a).
In recent years we have demonstrated
the value of drip treatments both as crop
termination treatments in the spring and as
preplant treatments in the fall under new
plastic. This past year we were able to show
that two drip tapes per bed, rather than one,
significantly improved nematode control and
strawberry yield (Fig. 1). Even with methyl
bromide applied by chisels in the row before
planting, there was an increase in berry yield
which could not be attributed to the fumigation
effect, but more likely to the improved
nutrition and water availability with the second
This same research demonstrated that
PIC Clor 60, even at 300 lb/a did not really do
a very good job of controlling sting nematode
because of the reduced rates of Telone applied
at the expense of the increased level of
(Continued on page 10)

(Continuedfrom page 9)
chloropicrin. It simply was not enough
Telone for a high nematode pressure field.
Looked at another way, there was too much
chloropicrin, not a particularly effective
nematicide, for a hot nematode field. This
fall we will focus our research on Telone
Inline as a fall treatment in combination with
different spring crop termination treatments
such as Telone EC (10-12 gal), Vapam (75
gpa), or Kpam (60 gpa). We will also focus
on prebed applications of Telone C35, chisel
applied to flat ground in advance of bed
formation to avoid respirator requirements
for workers in the field when it is applied in-
bed with backswept knives. We would like
to conclude, as we have in other newsletter
articles, with a bulleted list of considerations
that growers should be aware of and follow
to the extent possible for all drip applied


Maintain adequate soil moisture prior to drip
fumigation. Do not begin fumigant injection until the
bed is preirrigated. Fumigants move vertically in
dry soils and need water filled pore spaces to
encourage lateral movement of the water front.

Start with a clean, leak-free drip tape (chlorine,
acids, peroxides).

During injection, insure adequate / uniform line
pressure (10 psi) between and along rows. Monitor
line pressures at row ends, particularly if a Mazzei
Injector is used for chemical injection. Injection
periods should be extended if suitable pressure (10
psi) cannot be achieved. Growers should remember

Fig. 1

that one word describes fumigation uniformity along
and between field rows: PRESSURE.

Very high end-of-season nematode populations
require maximum label rates of fumigant application.
Remember, there is no way to effectively control the
nematode after planting.

Insure lethal concentration of fumigant in irrigation
water for sting nematode control (1000 ppm Telone II
or Telone Inline; 1500 ppm Vapam; 2800 ppm
KPAM). Do not inject a Telone product at greater
than 1500 ppm or Chloropicrin at greater than 1500
ppm because of possibilities for irreparable damage to

To maximize lateral spread of the fumigant in
water phase (50-60% of bed with single tape), plan to
inject fumigant at least 3 hrs (i.e., 200 minutes or
more). Split applications are not recommended since
they have not demonstrated improved lateral
movement and persistence of fumigant gases across
the bed. Also, avoid the temptation of reducing the
injection period of the fumigant because of wet,
saturated soils, and weather forecasts predicting
additional rainfall. Short injections to wet soils will
produce disappointing results. A new level of patience
we believe is in order.

Consider a second drip tape to improve lateral
distribution of the fumigant in water phase (75-85%)
and cross bed movement in gas phase, as well as to
increase fumigant performance, crop yield, and pest
control efficacy.

Under new plastic, burial of the drip tape 1 to 2
inches should prevent line kinking of the drip tape
along the row. It does however make it more difficult
to replace if the need arises.

Flush the irrigation system and drip tape following
fumigant injection for at least 20-30 minutes. Consider
longest / farthest run distance and 2x tube volumes.

Do not assume that main and submain valves

Fig. 2

Times Goes II
Electronic &

Due to budget cuts, UF has
eliminated bulk mail, so starting this October
BVT will no longer be mailed. If you are
currently receiving a paper copy of the newsletter
and would like to continue receiving the
information it contains, please contact Christine
Cooley at ccooley@ufl.edu or 813-634-
0000. You can also view current and past issues
on our strawberry website at http://
strawberry.ifas.ufl.edu. Limited copies will be
made available at the Hillsborough County
Extension Office and at GCREC in Balm.

Vegetable crops lose maneb and
gain new Bravo uses, while the
EPA delays review to expand the
mancozeb label.
Gary E. Vallad

Last spring, United Phosphorus, the sole
registrant of technical maneb voluntarily
cancelled the registration for maneb. For several
vegetable crops, maneb is the only broad-
spectrum fungicide available. A registration for
mancozeb, an ideal broad-spectrum replacement
for maneb, was submitted to the EPA for review
this summer. However, the review date for this
petition has now been postponed until March
2010. This has reignited fears that existing
stocks of maneb will be gone before the end of
2009. Florida pepper producers would be most
adversely impacted by such a shortage, as they
rely on maneb for mixing with copper-based
fungicides to control bacterial spot caused by
Xanthomonas euvesicatoria (formerly X
campestris pv. vesicatoria) in which copper-
tolerant isolates are predominant throughout the
state. Mancozeb and maneb are both
dithiocarbamate fungicides commonly used as
protectants against a broad spectrum of fungal
pathogens on numerous vegetable and fruit crops.
Mancozeb is also labeled as a common tank mix
partner with copper-based pesticides for the
control of foliar diseases caused by bacterial

pathogens, such as phytopathogenic species of
Xanthomonas and Pseudomonas on tomato, but not
pepper. An attempt this spring to develop a
Section 18, crisis exemption, for mancozeb on
pepper was abandoned, as maneb supplies were
found to be adequate. A new survey in August
reached a similar conclusion. While there should
be adequate stocks of maneb available for this fall
and the following spring, there is no guarantee that
supplies won't be redistributed if a demand arises
elsewhere (ie. Mexico/California). As a
precaution, pepper growers should contact their
local distributor to ensure adequate availability
through next spring. Hopefully, at such time, the
EPA will have reviewed the mancozeb registration
which will include expanded usage on several
vegetable crops, including pepper. A letter was
also sent by Mike Aerts of the Florida Fruit and
Vegetable Association, urging the EPA to expedite
the review for the new uses of mancozeb.
Regardless, a new label will probably not be
available for use until the summer of 2010 at the
earliest and many other crops will still remain
orphaned with no broad-spectrum fungicide
available (see table below).
Growers should also be aware that the EPA
did approve the addition of several new vegetable
uses to the Bravo (chlorothalonil) label. These
additions are summarized in the table below.
Growers using old stocks should contact their
distributor for the new label. The expansion of the
Bravo label will satisfy some of the needs for broad
-spectrum fungicide control in crops orphaned by
the loss of maneb. Unfortunately, Bravo
(chlorothalonil) is not effective against bacterial
diseases and will not replace maneb as an effective
tank-mix partner with copper for the control
bacterial spot on pepper or other vegetables.

Listing of Florida vegetable crops affected
by the loss of maneb, and Bravo
(chlorothalonil) label expansion on Page 12.

Please remember...
The use of trade names in this publication is solely for
the purpose of providing specific information. It is not a
guarantee or warranty of the products named and does
not signify that they are approved to the exclusion of
others of suitable composition. Use pesticides safely.
Read and follow directions on the manufacturer's label.

Florida vegetable crops affected by the loss of maneb, and Bravo (chlorothalonil) label expansion.

Registration status as of August 2009
Crop (existing stocks) Mancozeb Chlorothalonil
Mancozeb Petitioned Crops
Broccoli Yes No* Yes
Cabbage Yes No* Yes
Lettuce Yes No* No
Peppers Yes No* Yes
Pumpkins Yes No* Yes
Squash, winter Yes No* Yes
Orphaned Crops lack supporting petition for mancozeb
Beans, dry Yes No Yes
Brussels sprouts Yes No Yes
Cauliflower Yes No Yes
Chinese cabbage Yes No Yes
Collards Yes No No
Endive Yes No No
Eggplant Yes No Yes
Kale Yes No No
Kohlrabi Yes No Yes
Mustard greens Yes No No
Onion, green Yes No Yes
Turnip tops Yes No No
*New mancozeb uses being sought by Dow, DuPont, or IR-4; expected March 2010.

Pesticide Registrations and Actions
* Based on a request by IR-4, the EPA has approved tolerances for the fungicide cyazofamid
(Ranman). Tolerances of importance to Florida include okra and fruiting vegetables (group
8). (Federal Register, 7/8/09).
* Based on a request by IR-4, the EPA has approved tolerances for the insecticide/miticide fenpy-
roximate (Portal). Tolerances of importance to Florida include cucumber, okra, melon (group
9A), and fruiting vegetables (group 8). (Federal Register, 7/29/09).
* Based on a request by IR-4, the EPA has approved tolerances for the insecticide indoxacarb
(Avaunt). Tolerances of importance to Florida include bushberry (blueberry). (Federal Regis-
ter, 7/10/09).
* Based on a request by IR-4 and Bayer CropScience, the EPA has approved tolerances for the
fungicide fenamidone (Reason). Tolerances of importance to Florida include cilantro, okra,
turnip greens, and root vegetables except radish (group 1B). (Federal Register, 7/15/09).

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