Group Title: Berry/vegetable times.
Title: Berry/vegetable times. February 2002.
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 Material Information
Title: Berry/vegetable times. February 2002.
Uniform Title: Berry/vegetable times.
Physical Description: Newspaper
Creator: Gulf Coast Research and Education Center, Institute of Food and Agricultural Sciences, University of Florida, University of Florida
Publisher: Gulf Coast Research and Education Center, University of Florida
Place of Publication: Dover
Publication Date: February 2002
 Record Information
Bibliographic ID: UF00087388
Volume ID: VID00002
Source Institution: University of Florida
Rights Management: All rights reserved by the source institution and holding location.


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IntsluLt if F nd and gtcrulturrldQcen~cr
A monthly newsletter of the University of Florida Institute of Food and Agricultural Sciences, Gulf Coast Research and Education Center, and Florida Cooperative Extension Service.
Gulf Coast Research and Education Center, 13138 Lewis Gallagher Road, Dover, FL 33527 (813) 744-6630 SC512-1160 Website: http//
Editors: Dan Legard (legard2( & Craig Chandler I .. ,,1l .dII i )esign & Layout: Christine Manley (cmanlev(&; Director: Jack Rechcigl
February 2002

Carolina Geranium Contributes to
Spider Mite Problem
Jim Price

Soon after
transplants are set,
tiny Carolina
geranium seedlings
begin to appear and
by January these
weeds can become
large. As Carolina Carolina geranium.
geranium plants grow they become excellent
reproductive hosts for the twospotted spider mite
and the tumid spider mite (the purple-red

ar ;

Spider mite.

colored mite),
complicating the
management of these
The weed is not
such a problem when it
grows from a transplant
hole in the plastic mulch,
because in that

position miticide applications will kill resident
mites on both the weed and the strawberry.
Unfortunately, the Carolina geranium can grow
in the row middles, row ends, on field and
access road margins
and on fallow,
recently tilled fields,
places not normally
treated with miticides.
Spider mite
populations increase
on the Carolina
geraniums in these
places and transfer to
the strawberry crop,
insuring a regular re- Leaf inspection.

infestation. The mites can walk from the weeds
to nearby strawberry plants or be carried greater
distances in air currents on strands of silk they
Good weed management is essential for
growers depending on miticides for spider mite
control. The condition is not so problematic for
growers depending on biological control with
Phytoseiulus persimilis. This predator easily
finds the available mites on the weeds and controls
the pest mites. Growers can evaluate their
vulnerability to the problem by finding the
Carolina geranium on their farm and surveying
the underside of the leaves for spider mites.
Growers who use biological control should find
predators about as often as spider mites. The
Carolina geranium problem presents another
good reason to consider biological control of
spider mites. For more information on spider
mite control visit this link on our website

New SpinTorR 2SC
Tool in Strawberry
Jim Price

SpinTor 2SC
(spinosad), by Dow
recently was
approved for use in

is a Valuable

Leaf tier caterpillar.

strawberry to control
armyworms, omnivorous leaf tier,
strawberry leaf roller, and thrips. This
product represents an important addition to
the collection of insecticides available to

strawberry growers.
SpinTor is a new type of
insecticide that is a combination of two
toxins (spinosins A and D, thus the common
name "spinosad") obtained from the
fermentation of a soil microorganism,
Saccharopolyspora spinosa (an
actinomycete). It possesses a favorable pre-

Volume 2

Issue 2

harvest interval (PHI 1 day) and re-entry
interval (REI 4 hours) and is compatible
with many beneficial insects and mites.
However, SpinTor is very toxic to
honeybees exposed to direct spray and it
should be applied only in the early morning
or late afternoon when honeybees are not
foraging. SpinTor is a contact and stomach
poison and is not systemic in the plant. A
suitable adjuvant and an excellent spraying
technique may enhance the ability of
SpinTor to contact and kill thrips in
flowers where they are protected.
Growers who employ Phytoseiulus
persimilis for spider mite management may
welcome this product for thrips control,
given that no other material now available
has this unique combination of thrips
control, compatibility with P. persimilis and
short REI and PHI. When using this product
to control caterpillars, the egg or young
larval stages should be the target. This
timing makes regular scouting of the crop
important. Four (6 ounces/acre) to seven (4
ounces/acre) applications can be made to a
crop, depending on the rate used. In no case
can more that 29 ounces/are be applied to a
The industry is fortunate to have an
additional choice of caterpillar and thrips control
agents. Good resistance management practices
such as scouting, applying SpinTor only when
conditions warrant, and rotating among classes
of chemicals are important for the long life of
this product in the strawberry industry.

From an Aussie Point of View
Mark Herrington, Sr. Horticulturist
(Breeding) Queensland Horticulture

Some thoughts from 'an Aussie' visiting
your enchanting state. Firstly, I am grateful to
have had this opportunity. It has been rewarding
and stimulating to work with Dr. Chandler and
the UF strawberry team at Dover, and to meet a
number of growers. The Florida strawberry
industry has a major asset in this UF group as
you would all know already. Part of my work
here was to work with Dr. Chandler on methods

to better select parents and new varieties. One
of the first questions that arises in this work is,
what should a variety be like?
The bottom line is that the consumer
must be happy to buy strawberries; in fact, the
consumer should be excited to buy them. Our
job, the job of everyone in the production and
marketing chain from the breeder, researcher
and the grower through the retailer is to offer
strawberry fruit that are exciting or at least
pleasurable to eat. We, who are lower in the
chain, can be happy with a profit, but the
consumer only buys strawberries for the
experience, so we need to make sure they have a
good experience.
We in the strawberry industry know that
not all strawberries will give the same
experience to a consumer. Now, you will have
noticed that different people like different types
of apples. The same is true with strawberries.
However, while one can choose from a variety
of 'named' apples in the supermarket, at present
the consumer does not get the choice for
strawberries. Consumers should know that
different varieties of strawberries give different
experiences. Then they can choose the
experience (variety) they like. It is better to
have to make a choice between this name or that
name (variety) of strawberry than between a
strawberry and another fruit. A good name for
the variety adds to the experience.
The consumer may have to pay more to
get their preferred variety, but they will do that
if they had a good experience. G'day!

Reminder on using bloom sprays to
control Botrytis fruit
Dan Legard

As the weather warms
up and the strawberries began
to flower heavily, I would like Strawberry blossoms.
to remind growers and consultants about some
of the keys for controlling Botrytis fruit rot.
Research conducted at the Dover research center
has found that
fungicide applications
during the peak
bloom period in
February are the most
effective way to

Botrytis fruit rot.

Volume 2

Issue 2

control Botrytis. Weekly applications of captain
or thiram at full-labeled rate during the last two
months of the season can provide excellent
control of Botrytis. However during peak bloom
periods in February we found that two to four
bloom applications of Elevate? and/or Switch2
combined with the weekly applications of captain
or thiram provided the best control of Botrytis
fruit rot. We recommend that growers continue
to apply captain with the Elevate and/or Switch
applications if they want to also control
anthracnose fruit rot. Additional information on
controlling Botrytis fruit rot can be found on our
website at in our
Production Guide.

New powdery mildew fungicide in the
Dan Legard

Dow AgroSciences is working with
University researchers and IR-4 to complete
studies needed to bring a new fungicide called
quinoxyfen to market. This fungicide is only
effective against fungi that cause powdery
mildew and is classified as a reduced risk
fungicide. This means that it has low toxicity
and is compatible with IPM programs. On
strawberry quinoxyfen has provided excellent
control of powdery mildew in research trials
conducted by Dr. Doug Gubler at the University
of Califomia- Davis. Quinoxyfen has a unique
mode of action for controlling fungi making it
an excellent rotation partner for managing
fungicide resistance in powdery mildew. This
product will probably be called Quintec but will
not get a full label for strawberry until 2004-
2005. For more information on powdery
mildew control visit our website at the following
provides control information, and this link will
provide a list of fungicide recommendations
fungicide recommendations 2000.htm

Petiole Sap Testing
John R. Duval

Monitoring the nutritional status of
strawberry plants over the course of the season

is critical for optimizing yields. Deficiencies in
the early season can decrease yields later in the
year. Analysis of plant tissue is the best way to
determine how well a fertilization program is
meeting the demands of strawberry growth.
There are means to determine the plants nitrogen
(nitrate) and potassium levels directly in the
field. The use of hand held ion specific
electrodes (Cardy meters) provide a simple and
effective way of doing this. Ten to 15 petioles
are removed randomly from actively growing
plants then pressed to remove sap from the
petioles. This sap is then placed on the electrode
and a value in parts per million is given for the
specific ion. This information can be used to
increase or decrease the fertilization. The
sufficiency range of values for N (nitrate) and K
are given below. These numbers are a guide.
Weather conditions may decrease (if
temperatures are cool) or increase (if
temperatures are warm) desirable N and K
values during December, January, and February.



Petiole sap concentration (ppm)

N (nitrate)

K (potassium)

Center Update Christine Manley

Our center was recently host to one of the largest tour
groups in our history. Garst Seed Company located
in Indiana organized a tour of 400 people to GCREC-
Dover on February 5th. Guests were introduced to
each program involved in our research, and of course,
invited to taste our fruit. Each program had a station
set up at the front field or near the greenhouses, and
the tour proved to be a great success with many
compliments and probing questions from the
participants. Garst Seed Company specializes in
soybeans and corn. Their annual conference is held
in different locations throughout the country and
always includes an agricultural education day. The
participants also visited a tropical fish farm during
their tour day. With 3 busloads per hour over 5

sessions, our faculty and staff had their work cut out
for them. Photos of the event are on the next page.

Volume 2

Issue 2

John Hogue and Curtis Nagel, in Dr. Jim Dr. John Duval described cultural
Price's program, explained the procedure for management practices to the group.
using biological vs. chemical control of
twospotted spider mites.

Dr. Dan Legard introduced our guests to diseases that affect Florida strawberries.

The use of trade names in this pubhcation 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 andfollow dire ctons on the manufacturer's label
The Institute of Food and Agricultural Sciences is an equal opportunity/affirmative action employer authorized 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.


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