Cooperative Extension Service  ________________________________________________ Institute of Food and Agricultural Sciences

Although Tropical Storm Isidore gave Florida a wide berth as it passed into the Gulf last week, rain bands associated with the storm bought widely scattered showers to most areas of South Florida in passage.  Overall, hot and wet weather punctuated by scattered afternoon showers continues to be the norm.  Temperatures in most areas have been averaging a few degrees above normal with high in the upper 80’s to low 90’as and nighttime lows in the mid 70’s.  Rainfall totals have varied widely across the area with some areas receiving from 3 – 5 inches will other places saw only trace amounts.

Fall and winter crop planting and land preparation is actively progressing going strong across all south Florida growing areas.   Respondents in the Homestead area report that land preparation is moving into high gear now that threats from 'Isidore' and 'Lili' are either past or passing and planting of tomato, pepper, eggplant, squash, cucumber, bean, and a variety of specialty and ethnic crops is underway.  Rain and threats of rain from Isidore caused a few delays in operations in some areas but in general most growers indicate that operations are going according to schedule.

Okra harvest remains active in Dade County.  Reports indicate very light supplies of cucumbers, eggplants, peppers and squash are beginning to come onto the market from various South Florida locations

FAWN Weather Summary

Date	Air Temp (°F)		Rainfall Hours Below Certain Temperature          (hours)
	Min	Max	(Inches)	40°F	45°F	50°F	55°F	60°F	65°F	70°F	75°F
Ft L'dale
9/17 - 10/2/02	75.1	91.1	1.21	0.0	0.0	0.0	0.0	0.0	0.0	0.0	0.0
Ft Pierce
9/17 - 10/2/02	70.3	92.6	0.17	0.0	0.0	0.0	0.0	0.0	0.0	0.0	47.1
Homestead
9/17 - 10/2/02	73.4	90.2	2.42	0.0	0.0	0.0	0.0	0.0	0.0	0.0	20.2
Immokalee
9/17 - 10/2/02	72.5	92.6	0.0*	0.0	0.0	0.0	0.0	0.0	0.0	0.0	60.9

* Note due to technical difficulties no rainfall totals are available from Immokalee

The short term forecast from the National Weather Service in Miami calls for drier conditions over the next few days as Hurricane Lili moves into the central Gulf of Mexico allowing less humid air to move over the peninsula.  The forecast for the next few days calls for a chance of afternoon and evening showers and thunderstorms each day with lows in the lower to mid 70s and highs in the lower 90s.

For additional information, visit the National Weather Service in Miami website at http://www.srh.noaa.gov.mia

Insect and disease activity continues to be relatively light in most places.

Around Immokalee, growers and scouts are reporting that worm pressure has increased marginally following the full moon but overall worm pressure is still below last season.  Scouting reports indicate that beet armyworms are the most common but fruitworms, hornworms, southern armyworms and loopers are also being found.  Fall armyworms are beginning to show up on sweet corn.  Specialty growers report a medium to high incidence of leaftiers in vegetable amaranth.  Growers report good control with Bt, Confirm, Spintor and Avaunt.

Melonworm pressure is reported to be very high in cucurbits around southwest Florida.

Respondents in Homestead indicate that worms have been consistent on a wide variety of crops with southern armyworms, beet armyworms, fruit worms, loopers, and horn worms all being found.

Reports from Palm Beach area also note an increase in worm activity.  Scouts indicate significant beet armyworm pressure in pepper.  Growers are also seeing southern armyworms and respondents indicate that loopers are the “worm of the week” in tomatoes.  Imported cabbageworms have been active in specialty crops.

The beet armyworm Spodoptera exigua H. originated in Southeast Asia. It was first discovered in North America about 1876, and reached Florida in 1924.  Seasonal activity varies considerably according to temperature. In Florida, all stages can be found throughout the year, although development rate and overall abundance are reduced during the winter months. The life cycle can be completed in as few as 24 days, and six generations have been reared during five months of summer weather in Florida.

Eggs are laid in clusters of 50 to 150 eggs per mass.  Normal egg production is about 300 to 600 per female. Eggs are deposited on the lower surface of the leaf, often near blossoms and the tips of branches. The eggs are greenish to white in color, and covered with a layer of whitish scales that gives the egg mass a fuzzy or cottony appearance. Eggs hatch in two to three days during warm weather.

There normally are five larval instars.  The larvae are pale green or yellow in color during early instars, but acquire a dark lateral stripe during the fourth instar.  The larva of beet armyworm may be confused with southern armyworm, Spodoptera eridania, but southern armyworm can be distinguished by the presence of a large dark spot laterally on the first abdominal segment that disrupts the lateral stripe.

The moths are moderately sized, the wingspan measuring 25 to 30 mm. The forewings are mottled gray and brown, and normally with an irregular banding pattern and a light colored bean-shaped spot. The hind wings are a more uniform gray or white color, and trimmed with a dark line at the margin.

The beet armyworm has a wide host range. Susceptible vegetable crops include asparagus, bean, beet, broccoli, cabbage, cauliflower, celery, , corn, cowpea, eggplant, lettuce, onion, pea, pepper, potato, radish, spinach, sweet potato, tomato, and turnip. Weeds suitable for larval development, include lambsquarters, mullein, pigweed, purslane, Russian thistle, and parthenium.

Larvae feed on both foliage and fruit.  Young larvae feed gregariously and skeletonize foliage. As they mature, larvae become solitary and eat large irregular holes in foliage.  Tomato fruit is most susceptible to injury, especially near fruit maturity, but beet armyworm is not considered to be as threatening to tomato as is the corn earworm, Helicoverpa zea.

Pheromone traps can be used to detect the presence of adult beet armyworm. The Florida Tomato Scouting Guide recommends an action threshold of 1 larvae per 6 plant pre-bloom and 1 larvae or egg per field post-bloom.  Regular monitoring of crops, probably about twice per week, is recommended because adults frequently invade from surrounding crops or weeds.

Numerous native natural enemies have adapted to this pest.  These include both predators and parasitoids.  Fungal diseases and a nuclear polyhedrosis virus may also inflict some mortality.  The important mortality factors vary among crops, and among geographic regions.

Insecticide resistance has become a problem in management of this insect and growers are advised to rotate insecticide classes.  Intensive use of insecticides for armyworm control in vegetables may also stimulate outbreaks of other pests, such as leafminer.

B.T. products provide fair control.  Only products made from the aizawai strains such as Agree and Zentari are recommended.

In recent years, a number of new effective lep materials based on “new” chemistry have been released.  These include Avaunt, Confirm and Spintor.  The new chemistry has several advantages over Bt’s including rainfastness, and some translaminar activity.  In addition, these products are somewhat selective and relatively soft on beneficials.

Some the older products also have a place in a rotation.  These products are very active, quick acting, economical, and have broad -spectrum activity.  They are especially useful in getting things back under control when pressure is high or population get out of control.  Includes in this group are the synthetic pyrethroids – Ambush, Asana, Baythroid, Fury, Mustang, Pounce etc., the carbamates – Sevin, Lannate and the OP’s – Diazinon, Guthion, Lorsban, and Monitor.

There have been reports of growers finding a few pinworms on tomato and eggplant transplants from East Coast production areas.  There have been no reports of these persisting in the field.

Respondents are reporting very low levels of leafminer activity in all areas.  Reports from Homestead indicate leafminer numbers are low overall, but are starting to build in beans.

Around Palm Beach, a few leafminers are being seen on eggplant and older tomatoes.

In southwest Florida, growers are reporting low levels of leafminer activity mainly on ends of rows and field margins.  Scouts report seeing a few adults and stippling here and there.

Reports from Homestead indicate that cucumber beetles widespread on beans, pepper, eggplant, and cucurbits.   Cucumber beetles are also reportedly active on beans in the Devil’s Garden area.

There are a few reports of adult pepper weevils beginning to show in traps around southwest Florida.

Reports from Immokalee indicate that broadmites appear to be on the rise in pepper fields and also in some eggplant.  Growers indicate that frequent rain is making it difficult to get much control with sulfur.

A few red spider mites have been noted in Palm Beach on eggplant.  These are largely confined to field margins and areas adjacent to ditch banks.

Growers and scouts in Palm Beach and Homestead also report seeing low but widely scattered broad mites on pepper and eggplant.   Reports indicate they are showing up just as plants start to bloom.  Broad mites are also being reported on basil.

Whitefly numbers are relatively low in all areas on most crops.

Respondents from Palm Beach have indicated some increase in numbers and have noted the presence of nymphs in older tomato fields that are a few weeks from harvest.  Growers are applying Knack and Courier as the effect of soil applied nicotinoids wear off.

Around Immokalee, whiteflies populations have reached high levels in a few squash fields where no nicotinoid was applied at planting.  Silverleaf symptoms have been noted in several of these locations.

To date, disease pressure has been light in most areas.

On the east Coast, reports indicate that bacterial leaf spot is present on pepper but that the incidence is low and occurrence spotty.   Bacterial spot is more widespread in tomato but incidence and severity remain low.

Scouts in Homestead indicate that the incidence and severity of bacterial spot being seen in tomato and pepper seems to depend on varieties more than a particular spray program.

Around southwest Florida, bacterial spot is spreading both in tomato and pepper.  In a few places, where infections came in early and rainfall has been high, reports indicate that bacteria is rampant in some tomato fields with infection at moderate levels and creeping higher into the canopy.

Growers and scouts on both coasts report finding a very low percentage of Tomato Yellow Leaf Curl infected tomatoes.  In most instances infected plants are few and far between although a few reports of infection rates approaching 1 % in older tomato fields have come in.

Growers from across south Florida continue to report finding transplants infected with a variety of diseases including bacterial leaf spot, pythium and Alternaria in trays coming from the plant house.  Part of an entire IPM approach to disease management should include inspecting transplants for problems prior to setting them in the field.

Reports from Palm Beach indicate no further problems with tobacco mosaic virus on jalapeno peppers.   Indications are that the disease is associated with infected seed lots.

A few isolated reports of southern blight are coming in from scattered areas around southwest Florida as well as Palm Beach County. Tomato plants with southern blight (Sclerotium rolfsii) display lesions on the stem at or near the soil line. These lesions develop rapidly, girdling the stem and resulting in a sudden and permanent wilting of the plant. White mats of mycelia are produced on the stem and in the adjacent soil.  In a few days, tiny tan to brown spherical sclerotia about 0.06 inches in diameter appears on the mycelial mat. The presence of abundant sclerotia is a good diagnostic feature.

Respondents around southwest Florida report that the incidence of damping off due to pythium appears to have declined somewhat in recent days.  There have been a few isolated reports of aerial pythium on tomato.

Reports from the east Coast indicate that Phythophtora capsici continues to be a problem on pepper as well as tomato and eggplant.  Although the incidence is generally low, 2- 3% infection rates have been noted in some fields that received heavy rainfall in recent weeks.

An isolated case of Cercospora leaf spot was reported on tomato in Immokalee.
 

Up Coming Meetings

Palm Beach County

October 16, 2002       General Standards/Core Test Review      8 AM - 10 AM
                                   Agricultural Row Crop Test Review s            1 PM - 3 PM
                                   Testing - Any Category                                 8 AM - 4 PM

                                   Belle Glade Extension Office
                                   2976 State Road 15
                                   Belle Glade

                                  Call 561- 996-1655 for more information.

St Lucie County

October 15, 2002      WPS Train- The Trainer   9:30 AM – Noon

                                   St Lucie County Extension Office
                                   8400 Picos Road
                                   Fort Pierce

                                  Call 772-462-1660 to for more information.

Southwest Florida

October 10, 2002        WPS Handler Training – Spanish   9:00 AM to Noon
                                    WPS Handler Training – English   1:00 PM – 3:00 PM
                                     Hendry County Extension Office
                                     1085 Pratt Boulevard
                                      LaBelle, Florida

                                     Contact 863-674-4092 for details.    Cost - $2.50

October 17, 2002       Vegetable Growers Meeting         6:00 – 8:00 PM
                                   Pepper Diseases and DuPont Product Up-date

                                    UF/IFAS Southwest Florida Research and Education Center
                                    Hwy, 29
                                    Immokalee

                                     Contact 863-674-4092 for details.

Why Fungicides Fail

Fungicides are an essential part of many vegetable disease management programs.  These crop protectants are not “magic bullets” and their use should not be looked upon as the sole disease management tactic for any vegetable crop.

Using fungicides as part of an integrated disease management program, along with varietal resistance and cultural practices that favor plant growth and development, will give the best results.  Several factors must be considered when deciding which fungicide to use and when to use it.

Fungicide Type - There are two broad categories of fungicides: protectant and curative.  The most common are protectant fungicides that must be applied before the plant is infected.  These fungicides are effective only where they are applied, so good coverage is essential.  Commonly used protectant fungicides for vegetables are Bravo (chlorothalonil, Syngenta) and mancozeb.

Curative fungicides can stop a disease even after it has begun, although there is usually a window of several days after infection when a disease can be cured.  These fungicides stop pathogens from growing in the plant tissues, and/or inhibit the pathogen from reproducing.

Most curative fungicides are systemic, meaning they can move through the plant from the point they are applied.  Ridomil Gold (mefenoxam, Syngenta) is an example of a curative fungicide.  Some of the newer fungicides, such as the strobilurins, e.g. Flint (trifloxystrobin, Bayer) and Quadris (azoxystrobin, Syngenta), are protectants but also have the local systemic activity.

Timing Of Application -When to apply fungicides depends on the biology of the pathogen, the weather, the rate of growth of the crop and the manufacturer’s suggested application interval.  For example, late blight of tomatoes can expand from a small number of plants to a full-blown epidemic in a few days if weather conditions are right (cool and wet).  Other diseases, such as early blight, progress more slowly, allowing a little less vigilance in fungicide application.  Most pathogens have distinct temperature and moisture optima, so knowing what these are will help with the timing of applications

Fungicide Failure - A common cause of fungicide failure is using the wrong one.  No fungicide is effective against all plant pathogens.  None work on viruses and phytoplasmas, and only a few inhibit bacterial diseases.

For example, Ridomil Gold is active against diseases caused by Pythium and Phtophthora, and against white rust and the downy mildews, but is ineffective against fungi in other genera such as Rhizoctonia and Sclerotinia.  Protectant fungicides generally have broader activity than curative systemic fungicides, which usually have a more specific mode of action.

Diseases caused by bacteria are problematic and, to date, only copper compounds and the plant activator Actigard (Syngenta) have shown the ability to reduce the severity of bacterial diseases.

Application Methods and Rates - When applying fungicides, the objective is to maximize coverage and minimize drift.  There are many nozzles and sprayers available, and nozzle pressure, tractor speed, and spray volume can all be adjusted for each formulation and crop.

Fungicides may fail if they are washed off the plant’s leaves, therefore many manufacturers recommend the use of spreader/stickers to increase both coverage and rain fastness.  Dosage also is critical for disease control.

Overuse or improper use can lead to fungicide failure and resistance to pathogens.  For example, Ridomil no longer controls late blight of tomatoes because resistance to the product has developed worldwide over the past decade.

Resistance tends to develop faster in pathogens that reproduce and spread quickly, such as bacteria and airborne spore forming fungi including those causing rust and powdery mildew.  Resistance also is more likely to develop with fungicides that have a very targeted mode of action.  The strobilurin fungicides, including Quadris and Flint, are in this category and resistance management strategies are included on the labels to assure that the fungicides are used properly.  These strategies primarily consist of limits on the total number of applications that can be made, and alternation with fungicides with a different mode of action.

When fungicides are used properly, they are valuable disease management tools.  However, proper use requires a good understanding not only of the positive characteristics of particular fungicides, but also of their limitation.

By Sally Miller, Richard Derksen, and Richard Riedel
American Vegetable Grower
September 2002

Pesticide Label Up Dates
 

• Avaunt, DuPont:  REI:  12 hours; PHI: three days; for control of tomato fruitworm, beet armyworm, southern armyworm and loopers in eggplant.  Note:  Do not apply more than 14 oz. of Avaunt per acre, per crop.  Minimum spray interval is five days.

• Avaunt, DuPont:  REI:  12 Hours; PHI: three days; for control of beet armyworm (low numbers), diamondback moth, cabbage looper, imported cabbageworm in Chinese leafy and root vegetables (Chinese broccoli, napa, Chinese mustard cabbage and kohlrabi).  Do not apply more than 14 oz. (four applications at the maximum rate) per crop per season.  Minimum interval between sprays is three days.

• The EPA has granted a specific exemption under Section 18 for the use of Sandea for the control of purple and yellow nutsedge in tomato.  A total of 43,200 acres of tomatoes may be treated in Florida.  A maximum of 0.094 lbs. of active ingredient or 2ox. of Sandea 75DF may be applied per acre per year.  Applications are to be made using ground equipment.  Aerial applications are prohibited.  A total of two applications per year of Sandea 75DF may be applied as either: (1) one pre-transplant soil surface of 0.5 to 0.75 oz. Sandea 42DF, (2) one “over-the- top” application 14 days after transplanting of 0.5-0.75 oz. product or (3) post-emergence application(s) of up to 1 oz. product to the row middles between planted rows of tomatoes may be made.

• Dual Magnum just received a TPR label for use under mulch in pepper.  For pre-transplant application, apply as a directed spray to pre-formed beds.  Apply to the soil surface of the bed as the last step immediately prior to the plastic-laying operation.  Apply using non-air assisted ground application field sprayers only, at a maximum rate of 0.064-0.95 lbs.  AI per acre in a minimum of 10 gallons of water per acre.  Do not harvest within 60 days of application or make more than two applications per crop.  Authorization and waiver agreements must be obtained from TPR, 407-894-1351, and signed prior to use.

• BASF received federal registration for Cabrio fungicide yesterday, Oct. 1, 2002.  Florida approval anticipated in November.  The Federal Label covers the following vegetables: Tomato, Pepper, Eggplant and Fruiting Vegetables - anthracnose, early blight, powdery mildew, Septoria leaf spot and late blight, Cucurbit Vegetables – Alternaria blight, anthracnose, Cercospora leaf spot, downy mildew, gummy stem blight, Microdochium blight, powdery mildew and target leaf spot, Carrot, Radish and Root Vegetables – Alternaria leaf spot, Cercospora leaf spot, powdery mildew and white rust, Onion and Bulb Vegetables – Alternaria purple blotch, powdery mildew and downy mildew.

To reserve a place contact Ed Jennings at 352-793-6376.

Quotable Quotes

You need only two tools. WD-40 and duct tape. If it doesn't move and it should, use WD-40.  If it moves and shouldn't, use the tape. – Anon.

Friends are quiet angels who lift us to our feet when our wings have trouble remembering how to fly. –Anon.

I have never let my schooling interfere with my education. -- Mark Twain

He had discovered a great law of human action, without knowing it - namely, that in order to make a man or a boy covet a thing, it is only necessary to make the thing difficult to obtain. -- Mark Twain

On the Lighter Side

Men vs. Women:

NICKNAMES  - If Laura, Suzanne, Debra and Rose go out for lunch, they will call each other Laura, Suzanne, Debra and Rose.

If Mike, Charlie, Bob and John go out, they will affectionately refer to each other as Fat Boy, Godzilla,              Peanut-Head and Scrappy.

EATING OUT - When the bill arrives, Mike, Charlie, Bob and John will each throw in $20, even though it's only for $32.50.  None of them will have anything smaller, and none will actually admit they want change back.

When the girls get their bill, out come the pocket calculators.

MONEY - A man will pay $2 for a $1 item he wants.

A woman will pay $1 for a $2 item that she doesn't want.

ARGUMENTS  - A woman has the last word in any argument.

Anything a man says after that is the beginning of a new argument.

MARRIAGE  - A woman marries a man expecting he will change, but he doesn't.

A man marries a woman expecting that she won't change and she does.

OFFSPRING - A woman knows all about her children. She knows about dentist appointments and romances, best friends, favorite foods, secret fears and hopes and dreams.

A man is vaguely aware of some short people living in the house.
 

WHERE GOD AIN'T

He was just a little boy, on a week's first day.
He was wandering home from Sunday School, and dawdling on the way.
He scuffed his shoes into the grass; he found a caterpillar.
He found a fluffy milkweed pod, and blew out all the "filler."
A bird's nest in a tree overhead, so wisely placed on high.
Was just another wonder that caught his eager eye.

A neighbor watched his zigzag course, and hailed him from the lawn;
Asked him where he'd been that day and what was going on.
"I've been to Bible School," he said and turned a piece of sod.
He picked up a wiggly worm replying, "I've learned a lot of God."

M'm very fine way," the neighbor said, for a boy to spend his time."
"If you'll tell me where God is, I'll give you a brand new dime."
Quick as a flash the answer came! Nor were his accents faint.
"I'll give you a dollar, Mister, if you can tell me where God ain't.
 

Contributors include: Joel Allingham/AgriCare, Inc, Karen Armbrester/SWFREC, Jim Connor/SWFREC, Bruce Corbitt/West Coast Tomato Growers, Fred Heald/Farmers Supply, Sarah Hornsby/AgCropCon, Cecil Howell/H&R Farm, Bruce Johnson/General Crop Management, Leon Lucas/Glades Crop Care, Gene McAvoy/Hendry County Extension, Alice McGhee/Thomas Produce, Jimmy Morales/Pro Source One, Tim Nychk/Nychk Bros. Farm, Chuck Obern/C+B Farm, Dr Ken Pernezny/EREC, Dr. Pam Roberts/SWFREC, Nancy Roe/Farming Systems Research, Wes Roan/6 L's, Kevin Seitzinger/Gargiulo, Jay Shivler/ F& F Farm, Ken Shuler/Stephen's Produce, John Stanford/LNA Farm, Mike Stanford/MED Farms, Dr. Phil Stansly/SWFREC, Eugene Tolar/Red Star Farms, Dr.Charlie Vavrina/SWFREC, Mark and Donna Verbeck/GulfCoast Ag.

The SW Florida Pest and Disease Hotline is compiled by Gene McAvoy and is issued on a biweekly basis by the Hendry County Cooperative Extension Office as a service to the vegetable industry.

Gene McAvoy
Extension Agent II
Vegetable/Ornamental Horticulture             863-674-4092 phone
Hendry County Extension Office                863-860-8811 mobile  Nextel agnet 28950
PO Box 68                                                863-674-4097 fax
LaBelle, FL 33975                                 GMcAvoy@mail.ifas.ufl.edu
 
 

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