Group Title: Berry/vegetable times.
Title: Berry/vegetable times. October 2005.
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Title: Berry/vegetable times. October 2005.
Uniform Title: Berry/vegetable times.
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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: October 2005
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Bibliographic ID: UF00087388
Volume ID: VID00038
Source Institution: University of Florida
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October 2005


Florida Cooperative Extension Service,
Hillsborough County
5339 CR 579, Seffner, FL 33584
(813) 744-5519 SC 541-5772
Alicia Whidden, Editor Mary Chernesky, Director
Gulf CoastResearchand Education Center
14625 County Road 672, Wimauma, FL 33598
(813) 634-0000 SC514-6890
Christine Cooley, Layout and Design
Craig K. Chandler, Co-Editor
Jack Rechcigl, Center Director

From your agent...
The Weather Outlook

The weather gums at
the Southeast Climate
Consortium are saying that
this winter is in a neutral
phase. This means there are
no moderating influences from
El Nino or La Nina to help
block freezing artic blasts so
the "front door" is open for
massive artic fronts to come
down and cause a major
freeze. Historically it is neutral
years when devastating freezes
have occurred.
Another weather cycle
apparently has started. The 30
year dry cycle, which started
in 1965, apparently ended
around 1995 and now we are
going into what they say will
be wetter conditions for the
next few decades. This is due
to the Atlantic Multidecadal
Oscillation or AMO. The
AMO lasts from 20 to 40
years and affects rainfall
throughout the US. Central
Florida is greatly impacted
since we receive 60% of our
annual rainfall during the
summer and this is when the
AMO has the greatest effect.
The AMO is a change in
temperature in the North
Atlantic Ocean and it only

takes one degree Fahrenheit
temperature difference to have
long lasting effects on rainfall.
The last time there was a
warm phase of the AMO
which lasted from 1925-1965
there was plenty of rainfall in
peninsular Florida even
though some areas of the US
received less. I know it is
hard to believe that right now
we are in a wet time since we
have had several very dry hot
weeks of weather. However,
by the end of August, many
areas in central Florida have
already received more rain
than their average yearly total.
So the water districts'
problem may not be one of
drought but of what to do with
all the extra rainfall.

,f&ciaz WhLdden
813-744-5519,ext. 134
ajwhidden@ifas. ufl. edu

(Continued on page 2)

IFAS is an Equal Employment Opportunity Affirmative Action Employer authored 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

October 2005

BerryNegetable Times

Berry/Vegetable Times

Early Season Disease Control
Natalia Peres and Jim Mertely

Root necrosis andAinhiitl u i ine fruit rot:
It is well-know that disease-free transplants are
one of the best means to minimize disease
problems during the season. However,
recognizing potential disease problems in
transplants is not always easy. Transplants
colonized by Colletotrichum acutatum often
appear healthy, although petiole lesions can be
occasionally found (Fig.1). In our last article,
we discussed our research findings on pre-
plant dip treatments to control root necrosis
caused by C. acutatum. This same fungus also
causes anthracnose fruit rot. Normally, few
fruit are affected by this disease when the first
crop is harvested in December and
January. This suggests that disease
management early in the season can be less
rigorous than those later on. Weekly
applications of captain from November through
January do not always improve early season
control of anthracnose or botrytis fruit rot.
However, these applications help to suppress
pathogen colonization and often increase
yields. Our present recommendation is to apply
a broad-spectrum protectant fungicide such as
Captan at the lower label rate early in the
season and to increase the rate in late January
or early February when disease pressure is
greater. Applications should start as soon as
possible after overhead irrigation has been
turned off. Cultivars vary in their resistance to
anthracnose fruit rot and this should be
considered when deciding on a fungicide
program. 'Sweet Charlie' and 'Carmine' are
highly resistant and regular applications of
Captan are usually sufficient for good
anthracnose control. 'Camarosa' and
'Treasure' are highly susceptible and Captan
applications should be combined with Abound,
Cabrio, or Switch later in the season. 'Festival'
is intermediate in susceptibility to anthracnose.

Powdery mildew:
Powdery mildew (Sphaerotheca macularis) is
a disease problem that often occurs early in the
season (Fig.2). Cultivars also differ widely in
their resistance to powdery mildew. 'Festival',
'Camarosa', and 'Winter Dawn' are fairly
susceptible to the disease. Fields with
susceptible cultivars should be surveyed
regularly during the early season. To control
powdery mildew on susceptible cultivars,
fungicides should be applied at the first sign of
disease. This is especially important when
using protectant fungicides such as elemental
sulfur. Systemic fungicides such as Nova,
Procure, and Topsin can control powdery
mildew if the pathogen population has not
become resistant to them. Strobilurin
fungicides such as Abound, Cabrio, and
Pristine are also effective in suppressing the
disease, but caution should be taken not to
exceed four to five applications per season.
Whenever possible, it is important to obtain
the information on their fungicide spray
programs from the nursery. Nursery
application of systemic fungicides that are also
labeled for field use should be considered on
the total limit of applications per crop season.

Angular leaf spot:
Disease-free transplants are also considered the
best way to avoid angular leaf spot caused by
Xanthomonasfragariae (Fig.3). The
development of the disease is favored by warm
days and cold nights usually observed early in
the season. Although copper fungicides can
suppress this disease, low rates should be used
to prevent phytotoxicity. Rain and overhead
irrigation are important means for dispersal of
this pathogen. Thus, minimizing the use of
overhead sprinklers during plant establishment
and for freeze protection will also reduce the
spread of the disease.

Colletotrichum crown rot:
Crown rot diseases also typically appear after
plant establishment early in the season. In

October 2005

Berry/Vegetable Times

Florida, Colletotrichum gloeosporioides is the
most common cause of crown rot disease
(Fig.4). Our most recent experiments suggest
that regular applications of Captan after crop
establishment should help to reduce losses to
Colletotrichum crown rot. In fields with a
history of the disease, applications of Topsin
M after rain events in the fall may also be
helpful. For more information, consult our
article on Colletotrichum crown rot in the May
issue of the Berry Times.

Fig.3. Angular leafspot symptoms on strawberry leaves

Fig. 1. Sporulation of Colletotrichum acutatum on

Fig. 4. Colletotrichum crown rot (C. gloeosporioides)

Fig.2. Powdery mildew symptoms on strawberry leaves

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

October 2005

Berry/Vegetable Times

Methyl Bromide and Field
Evaluation of Alternatives Fall 2005
J.W. Noling, UF/IFAS Citrus REC, J.P. Gilreath, UF/
IFAS Gulf Coast REC and Alicia Whidden,
Hillsborough Co. Extension Service

As we have reported in previous
newsletters, and as was presented at the recent
AgriTech 2005 Seminar in August, methyl
bromide availability continues to be one of the
hot topics of discussion within industry. Is it
any wonder since it was technically phased out
of production and use January 1, 2005 and is
now being made available to Florida
strawberry growers only through award of a
Critical Use Exemption (CUE). The CUE is a
temporary safety valve to make methyl
bromide available to users who have no other
economically viable or technically available
alternative to provide broad spectrum soilborne
pest and disease control. The CUE is an annual
award, designed by international agency to be
made more difficult to annually acquire. This
international agency United Nations Montreal
Protocol, also seeks to reduce the approved use
rate per acre every year, forcing growers to
annually produce with less. The total amount
of methyl bromide allowed for strawberry use
during the year is formula driven, relying on
use of remaining commercial stocks of methyl
bromide as part of the award, coupled with
those from other newly manufactured supplies.
So far, the industry has not experienced
shortage. This season it seems pretty clear, that
as long as someone is willing to pay $3 or
more per pound, methyl bromide availability is
not going to be a concern to strawberry
growers for fall 2005. What will it be next
year? How long before demands of reduced
use cannot be completely avoided through
political maneuvering, and shortages finally hit
the industry? Given current sentiments in
Washington, it is hard to conceive of a federal
rescue of methyl bromide for continued, even
judicious use. Unquestionably, there is
uncertainty about the future of Methyl

bromide, and since we cannot predict the
future, we believe growers should all be
developing a 'future plan' which explores and
minimizes dependence on methyl bromide as
the key component of their on- farm pest
management program.
If you have followed the results of
IFAS research efforts to identify methyl
bromide alternatives, you would recognize that
this is not going to be an easy, painless
substitution. It will involve new fumigants
such as Telone, Chloropicrin, Vapam, and
Kpam. It will involve separate applications of
different herbicides, applied before bedding
and maybe, depending on the problem, also
during the bedding operation. It will be a new
learning experience with new colored
cylinders, new odors, and even new production
practices for both broadcast and in-bed applied
herbicides and nematicides to name but a few.
We have never said it would be easy. What we
have said is that it will require patient and
willingness on the part of growers to
successfully and effectively implement. It will
require planning horizons which account for
unexpected delays, including breakdowns,
hurricanes and no-name storms.
There are other reasons to trial methyl
alternatives. For example, there is an
obligation, on the part of the strawberry
industry, to demonstrate to the international
agencies that ongoing efforts to trial the
alternatives is in effect. An industry goal is to
identify and document their use, including
their shortcomings and pest and yield
consequences if any. So, as important as it is
to your production plans, future CUE's are
dependent on some form of documentation
regarding the extent to which Florida
Strawberry Growers are not only trialing, but
implementing alternatives. Everything seems
to be linked together, one aspect influencing
the other and vise versa. And as far as we see
it, we have finally entered the time which we
call the 'plan able' future.

October 2005

Berry/Vegetable Times


Before proceeding, we would first like
to acknowledge our previous cooperators. We
surely would not know as much as we do if it
were not for a few visionary growers, who
through their generosity, provided onsite
access, equipment, labor, and other resources
to conduct replicated on-farm demonstration /
experimentation research. We would like to
thank those who have repeatedly allowed us to
advance the science on their farms. We are
also hopeful for new cooperators who will
allow us to expand into new areas of pest
management research, including influences of
the soil environment and production practice
on nematode population level and yield
consequence. This year our FALL 2005
RESEARCH PLANS are to characterize the
importance of:

1) The row middles as zones for survivorship
of sting nematode soil fumigant treatment
and as zones of origin for recolonization of
the strawberry bed.

2) The use of Vapam or Kpam as a post
harvest crop destruction tactic to
incrementally reduce nematode pest
population pressures at the conclusion of
the spring cropping season.

3) The use of Telone C35 (26 gal/a) and
Telone InLine ( 26 gal/a) applied in-bed as
an alternative to Methyl Bromide /
Chloropicrin for nematode and disease

4) The use of broadcast applied Devrinol (4 lb
ai./a) followed by an over the top bed spray
of Goal (2 qts/a) for strawberry weed

5) To evaluate the use of chisel plowing as a
means of destroying the soil compaction
layer prior to soil fumigation so as to

improve fumigant diffusion in soil and
nematode control.

6) To continue to evaluate the tolerance of
different strawberry cultivars to damage
caused by sting nematode in four grower
field demonstration trials.

7) To study the efficacy of different
formulations of methyl bromide applied
alone and or in various concentrations with
Chloropicrin for nematode, weed, and
disease control at the FSGA research farm.

8) To continue to evaluate the use of high
barrier and or virtually impermeable plastic
mulch films in conjunction with reduced
rates of methyl bromide and chloropicrin
for nematode and disease control and
strawberry crop yields.

We still believe it is imperative that
Florida strawberry growers actively continue
field testing of these alternatives, and to
collaborate, to the extent possible, with
University of Florida scientists involving
monitoring and documentation of treatment
differences within field demonstration trials.


1) For strawberry growers with nematode
problems, small-scale field evaluation of
Telone C-35 or Telone InLine, applied in-
row at application rates of 26 to 35 gallons
per treated acre.

2) For strawberry growers without nematode
problems, small-scale field evaluation of
chloropicrin alone, applied in-row at
application rates of 300 lb per treated acre,
should be considered for testing.

3) New formulations of methyl bromide/
chloropicrin such as 50 / 50, to determine

October 2005

Berry/Vegetable Times

the extent to which actual use of methyl
bromide can be reduced without
compromising yield or pest control.

4) For these small scale trials, use of
separately applied herbicide such as
Devrinol (4 lb ai./ acre) and or Goal (1-2
qt/a) should also be evaluated in
conjunction with the alternative fumigants
for weed control. For these trials, some
modification of fumigant injection
equipment may be required to be able to
dispense either Telone C35 or Chloropicrin
from 200 lb (15 gallon) pressurized
cylinders. Two weeks prior to Telone or
Chloropicrin application, growers should
consider deep chisel plowing of these
fields (or portions thereof) to destroy any
soil compaction or traffic layer, so as to
improve downward diffusion and overall
effectiveness of the alternative fumigants
in soil. And finally,

5) Consider the field installation of a roll or
two of a high barrier, virtually
impermeable (VIF) plastic mulch to
reduce field application rates and soil
emissions of methyl bromide or other
fumigants such as 1,3-D (Telone) and
Chloropicrin. Previous research has
repeatedly demonstrated that methyl
bromide use rate reductions upwards of
50% is possible without loss of pest control
or crop yield. Rate reductions of 20, 25, or
even 33% are suggested for small scale
treatment comparisons with a standard
dose of methyl bromide using a standard,
low density polyethylene mulch.

If a grower is interested in conducting a
field demonstration trial comparing an
alternative to methyl bromide, or simply
requires more information regarding the testing
process or a more complete enumeration and
description of other possible alternatives please
do not hesitate to contact either Alicia

Whidden (813 744-5519; or Dr. Joe Noling
(863- 956-1151 ext 1262);
jwn(, for more information.

Possible New Strawberry Pest
Jim Price, Gulf Coast REC

The Florida Department of Agriculture
and Consumer Services
Division of Plant Industry -
announced that the twobanded
Japanese weevil
(Pseudocneorhinus bifasciatus
Roelofs) has been discovered in
Florida for the first time. It was
collected in a soybean field in
the panhandle town of Chipley
(Washington County) and is a known pest of
woody ornamentals in the northern USA. It is
also known to feed on strawberries.
Adults of this insect feed on leaves and
the larvae feed on roots. Florida does not have
any current problems in strawberries with
daunting, root-feeding weevils as do many
other states. We do not know how this insect
would behave should it become established in
Florida's strawberry production areas, but it is
not considered an important pest of
strawberries where it presently thrives.
Members of the strawberry industry
should not be too concerned about this insect
presently. We must remain vigilant though to
detect any affinity to our strawberries early.
Photographs and additional information
can be found at the FDACS Website http//
www. doacs.

October 2005

Berry/Vegetable Times

The Potential of Particle Film
Technology for Improving Crop
Craig Chandler, GCREC

Current particle film technology is
based on kaolin, a white, non-swelling clay
that easily disperses in water and is chemically
inert. It is possible to produce kaolin particles
with specific sizes, shapes, and light reflective
properties, making them useful constituents in
paper, paint, cosmetics, and plastics. And
recent advances in kaolin processing,
formulating, and plant surface deposition
properties have opened new opportunities for
its use in agriculture.
The characteristics that make a particle
film effective include the following: spreads
and creates a uniform film; does not interfere
with gas exchange from the leaf; transmits
photosynthetically active light, but excludes
ultraviolet (UV) and infrared radiation to some
degree; alters insect/pathogen behavior on the
plant; and can be removed from harvested
commodities. Currently, a commercial particle
film material, Suriouind' crop protectant, is
being used on about 90% of the Pacific
Northwest pear acreage for the early season
control of psylla (the most important insect
pest of pear in the U.S.) and on approximately
20% of the apple acreage in Washington State
to reduce sunburn on the fruit.
Plant tissues coated with particle films
are altered visually and tactilely to insects.
Particle films also could alter the taste or smell
of the host plant. Laboratory experiments with
various insects have revealed that the primary
mechanisms of action are repellence or
deterrence of adults from treated foliage.
Particle film technology has the
potential to suppress some bacterial and fungal
diseases, presumably by physically interfering
with the infection process or by preventing the
adherence of inoculum to the plant surface, but
the environmental conditions and treatment
timing necessary for this to occur has yet to be

worked out in most cases.
Many horticultural characteristics,
including yield, have been improved by the
application of reflective kaolin particle film
materials. For example, in a California study,
the application of 3% Surround to citrus
reduced heat stress and resulted in higher yield
in two out of three years. However, the
interactions between environment, plant
species, and time of application need to be
determined to assure that the desired
horticultural response will occur and be of
economic value.
In preliminary studies at GCREC-
Dover during the 2003-04 and 2004-05
seasons, applications of Surround to
strawberry plants immediately after
establishment resulted in increased early yield.
This season at GCREC, 'Winter Dawn' plants
planted in late September will be treated with
Surround to reduce heat stress, and their early
yields will be compared to the yields of
untreated control plants.

'This article is based on a technical paper in
Horticultural Reviews, Volume 31, written by two
USDA scientists, soil scientist Michael Glenn and
entomologist Gary Puterka.

Chemically Speaking
Pesticide Regulations and Actions

On July 15, the Florida Department of
Agriculture and Consumer Services (FDACS)
conditionally registered the insecticide
dinotefuran (Venom 20SG) for control of
whiteflies, leafminers, thrips, and other insects
in fruiting vegetables, cucurbits, head and stem
brassica, grape, potato, and cotton. The EPA
registration number for the Valent U.S.A.
Corporation product is 33657-17- 59639.
(FDACS PREC Agenda, 8/4/05).

October 2005

Berry/Vegetable Times

The First Strawberry Season at the New
Christine Cooley, GCREC

The strawberry fields at the new Gulf
Coast REC have been prepped and are ready
for planting. The following companies are to
be thanked for their generous contributions to
the center which enables the faculty and staff
to continue their research. JayMar Farms for
the use of equipment and labor; James
Irrigation donated the drip tape for the
irrigation; ProSource worked with their
supplier, Pliant Corporation, to provide the
plastic mulch; and Chemical Dynamics for the
soil fertility management services. Thanks
also to the entire strawberry industry in Florida

which continues to use UF cultivars. This year
it is expected that the UF cultivar 'Festival'
will be planted on over 50% of the West
Central Florida acreage. At GCREC, the trials
will focus on a variety of cultivars including
the newest UF release, 'Winter Dawn'. The
staff and faculty at GCREC are looking
forward to starting the season at the new

Current employment opportunity at
Gulf Coast REC

Agricultural Assistant (OPS)

The UF Gulf Coast Research & Education
Center, located in Wimauma (just south of the
Brandon/Riverview area), is looking for a part
time Agriculture Assistant to work 3 days/
week. Candidates for this job must be able to
work independently, drive a tractor, use a
respirator, and be able to obtain a Pesticide
Applicator License upon employment.

Responsibilities will include the application of
fungicides for research trials, spray equipment
maintenance, planting and maintaining
greenhouse plants (irrigate, fertilize, weed, and
apply pesticides as needed), scouting for
insects, and assisting with the planting,
harvesting & grading of strawberries.

Contact Teresa Seijo at (813) 634-0000 Ext.
3137 or

The University of Florida is an Equal Opportunity
Employer. The selection process will be conducted in
accord with the provisions of Florida's "Government in
the Sunshine" and Public Records laws. Search
Committee meetings and interviews will be open to the
public, and all applications, resumes, and other
documents related to the search will be available for
public inspection.


October 2005

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