Cooperative Extension Service 
                                                   ________________________________________________

Institute of Food and Agricultural Sciences



Hendry County Cooperative Extension Office
PO Box 68
Labelle, Florida 33975
863-674-4092


            Southwest Florida Vegetable Newsletter

November / December  2000

Index:

Calendar
Note from Gene
Methyl bromide: Are there effective alternatives?
EPA Issues Final Rule Regarding Section 18 Exemptions
New Tools
Never Use Other Chemicals As Pesticides
EBDC/ETU National Drinking Water Program
Preventative Medicine - Manage Fungicides Now to Thwart Resistance Later
Nematodes
EPA Findings
Organic Info Sources
Tomato Juice Fights Pneumonia
Pesticide Potpourri
Move Over Habanero
EPA Says Bt is OK
Federal News
Vegetable Producers at Risk
Health and the Environment
On the Lighter Side

Calendar

January 11 - 12, 2001         Florida Certified Crop Advisor Exam Study Workshop
                                            Citrus Research & Education Center, Lake Alfred, Florida
                                            Call FFAA at (863) 293-4827 to register

January 23, 2001              Production and Utilization of Composted Waste Materials to Improve Soils
                                          for Horticultural Cropping Systems
                                          Tropical Research and Education Center, 18905 SW. 280 St.
                                          Homestead Florida
                                          Contact Dr Monica Ozores-Hampton at 305-246-6340

February 2, 2001               Florida Certified Crop Advisor Exams (International and Southeast Regional)
                                           South Florida Community College, Avon Park, Florida   8 a.m. until 4 p.m.
                                           Note: the registration deadline for the exam was December 15, 2000

April 22-26, 2001              85th Annual Meeting of the Potato Association of America
                                          St. Augustine, Florida.

Hosted by the University of Florida/IFAS Hastings Research and Education Center, the conference will provide a forum for the presentation of new scientific information, conduct business of the association and facilitate fellowship among colleagues. The conference theme is Potato Plant Health into the New Millennium. Three days of stimulating paper sessions will be kicked off with a dynamic symposium entitled, "Impact of New and Emerging Diseases and Technologies on Potato Seed Certification" co-sponsored by the Certification and Pathology Sections of the PAA. Emphasis will be on challenging soil-borne diseases.
Oral and poster abstracts are being accepted through January 10, 2001.

For more information visit the conference web site: http://www.ifas.ufl.edu/~conferweb/paa/ or contact the University of Florida, IFAS Office of Conferences by phone (352) 392-5930 or by fax (352) 392-9734, or by Email: mtatlock@ifas.ufl.edu

August 3, 2001              Florida Certified Crop Advisor Exams
                                       South Florida Community College,  Avon Park, Florida
                                      Call FFAA at (863) 293-4827 for registration information.
 

Return to Index
Note from Gene

Gene McAvoy 
Vegetable Extension Agent II 
Hendry County Extension Office 
PO Box 68 
LaBelle, Florida, 33975 
863-674-4092 

gmcavoy@ifas.ufl.edu

Hope this finds you all well as we approach the New Year.  Looking back at some of the events of the past year and some that are just playing out as this newsletter is being published, it once again appears that agriculture will be called on to do more with less.

Provisions of the Everglades Forever Act now coming into force will dictate that growers in the C-139 basin reassess the method of applying phosphorus and possibly the amount of phosphorus used in vegetable production.  This is not an isolated phenomena - restrictions on fertilizers - particularly nitrogen and phosphorus - promise to become more widespread throughout the area.

The long-standing drought that has afflicted south Florida for the past few seasons, in conjunction with low lake and ground water levels will likely result restrictions on the amount of water available to growers before the end of the season.

As disheartening as some of these events may be, agriculture has always demonstrated tremendous resiliency and has emerged even stronger and more competitive in the face of adversity.

Without a doubt, the extension service and the state land-grant colleges have played a major role in supporting and promoting agricultural productivity and ensuring it's competitiveness, ever since the late 1800’s with the passage of the Morrill and Hatch Acts which laid the ground work for agricultural research and cooperative extension in the United States. Although extension in Florida has evolved overtime with changes in demographics and the changing needs of our clients,  we still maintain a fundamental commitment to agriculture - with a focus on sustaining it, helping it remain competitive, and keeping it profitable.

My colleagues and I acknowledge that in order to be able to help growers put research based knowledge to work to improve their lives and businesses, we must continue to build partnerships and coalitions with individuals, organizations, government agencies, and agricultural businesses around issues of mutual concern; and strive to help participants make informed choices using the best science based knowledge available.

With this in mind, those of us involved with the vegetable industry in southwest Florida have made a New Years resolution to make ourselves more responsive to growers needs.  We have allocated increased time for visits to growers fields and intend to give growers needs priority in our research and extension programming.

There is a catch, however, we need your help to allow us to better serve you.  You need to let us know what your problems are,  invite a researcher out to the farm, is there some on-farm trial that interests you?  We hope that we can work together to seek solutions for problems facing the industry.

Wishing you the very happy and prosperous New Year!

Return to Index
Methyl bromide: Are there effective alternatives?
The complete phase out of methyl bromide use in the United States by the year 2005 is causing concern among a number of growers, particularly fruit and vegetable growers in Florida and California.  This, combined with the likely loss of additional organophosphates (OPs) and carbamates under the Food Quality Protection Act (FQPA), is resulting in a search for effective alternatives– in many cases, alternatives that would fit in well with existing IPM programs.

This analysis of whether such alternatives do exist and how effective they are was prepared by the American Farm Bureau Federation (AFBF) and represents AFBF's opinion.

There has been a lot of activity surrounding the effort to find an alternative to methyl bromide.  To begin the process of finding a methyl bromide alternative, the United Nations Environment Programme (UNEP) formed the Methyl Bromide Technical Options Committee (MBTOC).  In a report issued in 1998, MBTOC says that “alternatives have been identified for virtually all uses of methyl bromide, and many of them are in use in different places around the world.”  The U.S. Environmental Protection Agency (EPA) agrees and says basically the same thing “similar pest control can be achieved with a combination of alternatives, materials, methods, and application practices.”

While Farm Bureau agrees that there are good replacements for methyl bromide for certain uses, as the MBTOC and EPA suggest, most of the replacements are either too costly, far less effective, or impractical to implement on farms. And for many other uses, there still aren't any effective replacements for methyl bromide.

To demonstrate its belief that effective methyl bromide replacements exist, EPA has published a periodic list of case studies to demonstrate “the fact that materials do exist which can manage pests where methyl bromide is now used.”  In 1995, EPA listed heat sterilization (steam) as its top alternative.  While heat sterilization does provide effective control for some pests now controlled by methyl bromide, it does so at a snail's pace while consuming enormous amounts of energy, water and money.  This is a technology that cannot be practically implemented on farms.

Current heat sterilization technology consists of a 25 million BTU heat exchanger capable of heating 250 to 300 gallons of water per minute to 200 -230 degrees.  Hot or boiling water produced by the heat exchanger is injected into the soil at a depth of up to 12 inches.  A 6 foot wide unit is pulled through a field by a tractor at a speed of 0.1789 miles per hour.  With this size unit and at those speeds, treatment of a 50 acre strawberry field would take 16 days of 24 hour operation.

Worse yet, this technology uses up to 70,000 gallons of water and 3,000 gallons of diesel fuel per acre.  Treating a 50 acre field would therefore consume 3.5 million gallons of water and 15,000 gallons of diesel fuel.  And heat sterilization doesn't kill anything other than nematodes.  More pesticides are needed for insect, weed and disease control.  While heat sterilization looked promising in 1995, EPA and MBTOC have now moved it off their list of effective alternatives.

Composting and the addition of manure, bio-solids, broccoli mulch and other organic materials also appear to have some promise at controlling a wide range of soil pests.  Again, however, composting is an alternative that cannot be practically implemented on farms.

Research by USDA's Agricultural Research Service and the University of Florida has shown similar marketable yields for pepper and tomatoes by replacing methyl bromide with solarization and the addition of a number of soil amendments including yard waste, poultry   manure and biosolids.  In fact, some of these combinations produce higher marketable yields than methyl bromide treated plots under certain conditions.  Conversely, in some test plots nematode populations actually increased, resulting in lower marketable yields.

In order to achieve these results, soil amendments had to be added at the rate of up to 60 tons/acre.  While this type of system might work on small acre plots, implementing this on a  widespread basis will be impossible.  Applying soil amendments to Florida's 40,000 acres of tomatoes at 60 tons/acre means 2.4 million tons are needed to cover all of Florida's tomato land.  A fully loaded truck can transport 20 tons.  Therefore, 120,000 truckloads would be needed for Florida's tomato acres.  A 1,000 acre farm will need 3,000 truckloads annually.  Costs for these types of soil amendments, including delivery, are conservatively estimated at $10/ton.  Costs will be much higher if yard wastes must be hauled from either Ft. Myers or the Miami area.  Costs for a 1,000 acre farm would equal $600,000 annually.

Non chemical treatments

The MBTOC/EPA list also consists of the following non chemical treatments that MBTOC and EPA say offer promise, but come with limitations which limit their use and applicability for commercial agriculture.  These alternatives include:

Crop rotation: Rotating crops to break up insect, disease and weed pressure has been an accepted and effective practice for centuries.  While crop rotation is somewhat effective, it is not economically feasible for a grower of a high value commodity (i.e., tomatoes, strawberries) to rotate to a crop (i.e., rye) that provides low or negative grower returns.

Flooding: Florida research indicates that soil flooding actually increases weed pressure and decreases marketable yields in tomato trials.  Plus, due to water restrictions in California and desert regions around the world, soil flooding cannot be considered a viable option.

Soil-less culture: The use of soil-less media have proven effective on small scale plots in greenhouses, but are not economically feasible or practical for large acreage.

Cover crops: Planting a 2 or 3 year cover crop before planting a crop dependent on methyl bromide (i.e., strawberry) is effective, but provides negative grower returns.

Resistant varieties: Many of these new resistant varieties include genetically modified plants, which are promising, but may meet with significant consumer resistance.

Solarization: Solarization means clear plastic is laid on the soil to heat the soil to temperatures high enough to kill pests.  Unfortunately, solarization only works in areas where the sun shines for long periods uninterrupted by clouds and where land can be left fallow for up to three months.  Very few areas in the U.S. meet these criteria.

Other alternatives

There are some good chemical alternatives to methyl bromide that are already available. The most prominent of these alternatives are 1, 3-Dichloropropene (Telone*), chloropicrin and metam-sodium.  In fact, Telone* when combined with chloropicrin and applied with drop irrigation under gas impermeable plastic tarps appears to be a viable alternative in both California and Florida.

Telone*, however, faces regulatory problems of its own.  For example, California regulations on Telone* prevent its application within 300 feet of any inhabited structure.  Chloropicrin also faces restrictions which may limit its use and effectiveness as a methyl bromide alternative.  Plus, the Telone* chloropicrin combination increases pre-harvest costs.

One of the problems encountered by researchers working on methyl bromide alternatives has been transferring technologies from the lab into commercial application.  For example, insects and nematodes raised in laboratory conditions do not react the same as feral insects.  Also, some methyl bromide alternatives work well in the lab, but perform poorly in the field when temperature fluctuations, unusual rainfall, wind and other weather conditions affect the performance of alternatives.

In the laboratory, conditions can be very closely monitored and controlled.  Researchers have learned that some methyl bromide alternatives require specific and complicated steps and techniques in order to be effective.  That same level of control is usually not available in large-scale, commercial trials.  As a result, technologies that looked promising in the lab haven't always transferred well when brought into the real world.

Gemplers
December 2000
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EPA Issues Final Rule Regarding  Section 18 Exemptions 
The EPA has issued a final rule regarding pesticide tolerances associated with emergency exemptions (Section 18).

No pesticide may be applied to a food crop unless the EPA establishes a tolerance for the pesticide on that particular food.  In an emergency, however, the Agency may grant permission for growers to apply pesticides to foods for which the pesticides are not registered.  In the old days, an emergency exemption was essentially an exemption from tolerance.  Under FQPA, the Agency must establish a tolerance if the emergency pesticide will be applied to a food.  To establish the tolerance, the EPA must determine that the pesticide application will not endanger children.  Keep in mind, the grower has an emergency, so the Agency must decide on the tolerance quickly.

This final rule is intended to ensure timely action from EPA by codifying the process used by EPA to establish a time limited tolerance for an emergency exemption.  Time limited tolerances will typically be set for 24 months to allow the treated crop from the emergency application to clear the channels of trade.  This final rule does not change the process that has been in place for several years.  The final rule can be read in the Federal Register at
http://www.access.gpo.gov/su_docs/aces/aces140.html

The Georgia Pest Management Newsletter
November 2000
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New Tools
Scientists with USDA report that a new strain of Beauvaria bassiana, BB-1200, is more effective than commercial strains against a variety of lepidopteran pests.  The USDA observed greater activity against all lepidopterans tested, including fall armyworm, beet armyworm, black cutworm, corn borer, and cabbage looper. B. bassiana (GHA) has been available commercially since 1995, but applications have been limited to the greenhouse.  For more information, contact Stephen Wraight at spw4@cornell.edu

Agricultural Research, 11-00

A strain of a fungal insect pathogen (Paecilomyces fumosoroseus Apopka 97) effective against greenhouse whitefly is moving toward registration in Europe.  The European product will be called PreFeRal.  There is not a commercial product currently marketed in the U.S.  Look for a similar product to be registered here soon.  Typically, biological products are much easier and cheaper to register with U.S. EPA.    Visit these web sites for more information.
http://www.biobest.be/eng/EPaecilomycesText.html

http://www.entomology.wisc.edu/mbcn/kyf403.html

IPMnet NEWS #83
November 2000
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NEVER USE OTHER CHEMICALS AS PESTICIDES!
Never use other chemicals as pesticides!

In many cases, other chemicals are going to be more dangerous and less effective for controlling the pests.  Gasoline is probably the all-time favorite for things like ants and yellow  jackets.  Gasoline is highly toxic, explosive, persistent, and carcinogenic; it penetrates the skin, and the fumes can cause irreversible brain damage.  Would you buy or use any pesticide with those qualities?

The Georgia Pest Management Newsletter
November 2000
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EBDC/ETU NATIONAL DRINKING WATER PROGRAM
This questionnaire has been prepared by the EBDC/ETU Task Force and LFR Levine/Fricke.  The intent of this questionnaire is twofold:  1) to inform you about the EBDC/ETU National Drinking Water Monitoring Program Survey and 2) to ask for your help and participation in this survey.  Please take a moment to read over the following information and, if your are interested in participating, fill out the questionnaire and return it to the contact below.

Some of the manufacturers of EBDCs and members of the Task Force include BASF Corporation; Griffin, LLC; Elf Atochem North America, Inc.; and Rohm and Haas Company.  The Task Force is sponsoring the EBDC/ETU National Drinking Water Program in order to collect groundwater data necessary to maintain their current registration of EBDC products.  The continued EPA approval of EBDC's is contingent upon the results of this study.

EBDC products are a class of chemical compounds used as fungicides to protect trees, nuts, fruits, and vegetable crops.  Some of the products containing EBDCs include Manex, Maneb, Dithane, Mancozeb, and Metiram.

Study Information

Questionnaire

If you are interested in participating in the program, please answer the following questions and return the completed questionnaire to SpencerMitchell.    If you have any questions, do not hesitate to call Spencer Mitchell at (850) 422-2555 or email: Spencer.Mitchell@lfr.com.
Thank you for your time and your interest in participating in the EBDC/ETU National Drinking Water Program.

1)  Has your crop been treated with EBDC compounds in the past 10 years?        Yes,        No.  If yes, which EBDC compound(s) were applied:                                                   Total acres treated:                .

2)  Approximately how close is your drinking water well to an EBDC use area?               (feet).

3)  Approximately how deep is groundwater in your area?                 (feet).

4)  How many drinking water wells do you own (include wells for home, packing houses, and barns)           .

5)  Approximately how deep is your drinking water well?                     (feet).
 

6)  Name:
     Address:
     City:                                        State:            Zip:
     Phone Number(s):

7)  Please indicate the location of your crop and well on the space provided.                  Indicate North
 
 
 
 

Comments:
 

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Preventative Medicine 
Manage Fungicides Now to Thwart Resistance Later
Your mother always told you that too much of a good thing may be bad, and mother knows best.  Using strobilurins, a relatively new class of fungicides, too often may speed organisms developing resistance to them.  A group of pesticide manufacturers, in conjunction with the Fungicide Resistance Action Committee, has developed management guidelines they hope will stave off resistance.  Key to their plan is rotating products with different modes of action and effective disease management.

By following the recommendations, you'll be able to slow resistance development and continue to have strobilurins as well as other fungicides as part of your disease-fighting toolbox for years to come.  Strobilurins include Abound and Quadris from Zeneca Ag Products, Flint from Novartis Crop Protection and Sovran from BASF Corp.

The guidelines by the manufacturers were prompted by a handful of diseases worldwide that have shown spotty resistance to strobilurins.  Among diseases affecting fruits and vegetables, only cucurbit powdery mildew appears to have developed resistance to the new chemistry so far.  The resistance is widespread in Japan, Taiwan and southern Spain in field and greenhouse melon and cucumber crops.  Researchers monitoring the situation have found no resistant strains in the United States or Mexico.

The 3 R=s: Rotate, rotate, rotate

One of the key components of the resistance management plan is to rotate different modes of action and not just different products, says Jerry Minore, BASF market manager for trees, vines and vegetables. "(Sovran, Flint and Abound/Quadris) are all in the same class of chemistry," Minore says. "They all attack the fungus with the same mode of action and at the same site."

Products that have modes of action different from strobilurins include sulfur, copper, sterol inhibitors and EBDCs.

The resistance recommendations do not take a blanket approach to all diseases on all crops.  Instead, the STAR (Strobilurin -Type Action and Resistance) Working Group factors in an organisms ability to become resistant to the chemistry.

The organisms causing late blight in potatoes and tomatoes (Phythophthora infestans), powdery mildew in cucurbits (Sphaerotheca fuliginea) and botrytis in grapes (Botrytis cinerea) are termed "high risk," meaning the potential to develop fungicide resistance is high.  Although the organisms that cause powdery mildew in grapes (Uncinula necator) and scab on apples (Venturia inaequalis) can develop resistance to fungicides, the potential is lower.

Know your diseases

Just as important as resistance management or maybe more so is disease identification, says Jim Wagner, a pest control advisor and partner in Hughson Chemical Co.

By properly identifying the disease, you, your consultant or PCA can prescribe the proper program to target the pests.
With the addition. of some of the newer classes of chemistry, Wagner says the job has gotten easier.  "I think our biggest concerns were what products we were going to lose," says Wagner, who spends most of his time helping almond growers.
"When we had Benlate only, our concern was what was going to happen in the future. Then came Rovral, followed by the sterol inhibitors.  The SIs have done two things:  They've broadened our disease spectrum as well as give us a different type of chemistry."

In almonds, growers typically apply two to three fungicides during bloom, so avoiding sequential applications isn't as critical as in other crops, where growers apply several additional applications of fungicides, Wagner says.

In stone fruit, for example, growers apply two to three fungicidal bloom sprays followed by several additional applications of fungicide with at least two fungicide sprays before harvest.

"When we had Benlate, we knew a resistance problem was going to develop," says Wagner, who used to work for DuPont Ag Products.  So the company educated stone fruit growers about the importance of combining two or more fungicides or using alternative chemistries.

Don't let history repeat

Dr. Alan MacNab, a Penn State University plant pathologist, is a strong supporter of resistance management and points to metalaxyl resistance as an example. "During the past decade, resistance developed in the late blight population," MacNab says.  "Before that time, metalaxyl (Ridomil) was oustanding for the control of late blight.  But where resistance developed, metalaxyl appeared to be almost worthless for late blight."

"After late blight developed resistance to metalaxyl, we didn't have anything that was nearly as good.  It is a tremendous loss to the growers when resistance does develop, so it's really worth while to do whatever needs to be done to make sure resistance does not develop."

How to Fight Fungicide Resistance

The following guidelines were developed by the Fungicide Resistance Action Committee. As with any fungicide, apply it according to manufacuturer's recommendations for the target disease or complex at the specific crop growth stage.  Effective disease management is a critical parameter in delaying the build-up of resistant pathogen populations.

Cucurbit Vegetables

Apply a maximum of three STAR sprays per crop.
Use a maximum of one STAR spray out of three fungicide applications.
Do not use consecutive applications of STAR fungicides.
Alternate STAR fungicides with fungicides from a different cross-resistance group.
Alternate STAR fungicides between successive crops.

Potatoes

Apply no more than one application before alternating to an unrelated fungicide that is effective in controlling the causal fungus.
Apply no more than six total applications per season.

Tomatoes

Apply no more than one application before alternating to an unrelated fungicide that is effective in controlling the late blight fungus.
For all other diseases, apply no more than tree sequential applications before alternating to an unrelated fungicide.
Apply no more than five total applications per season.

The Grower
September 2000
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Nematodes
Plant parasitic nematodes are microscopic roundworms which live in the soil and attack the roots of plants.  Crop production problems induced by nematodes generally occur as a result of root dysfunction, reducing rooting volume and foraging and utilization efficiency of water and nutrients.  Many different genera and species of nematodes can be important to crop production in Florida.  In many cases a mixed community of plant parasitic nematodes is present in a field, rather than having a single species occurring alone.  In general, the most widespread and economically important nematode species include the rootknot nematode, Meloidogyne spp., and sting nematode, Belonolaimus longicaudatus.  The host range of these nematodes, as with others, include most if not all of the commercially grown vegetables within the state.  Yield reductions can be extensive but vary significantly between plant and nematode species.  In addition to the direct crop damage caused by nematodes, many of these species predispose plants to infection by fungal or bacterial pathogens or transmit virus diseases, which contributes to additional yield reductions.

Biology and Life History

Most species of plant parasitic nematodes have a relatively simple life cycle consisting of the egg, four larval stages and the adult male and female.  Development of the first stage larvae occurs within the egg where the first molt occurs.  Second stage larvae hatch from eggs to find and infect plant roots or in some cases foliar tissues.  Host finding or movement in soil occurs within surface films of water surrounding soil particles and root surfaces.  Depending on species, feeding will occur along the root surface or in other species like rootknot, young larval stages will invade root tissue, establishing permanent feeding sites within the root.  Second stage larvae will then molt three times, to become adult male or female.  For most species of nematodes, as many as 50 to 100 eggs are produced per female,  while in others such as rootknot, upwards of 2000 may be produced.  Under suitable environmental conditions, the eggs hatch and new larvae emerge to complete the life cycle within 4 to 8 weeks depending on temperature.  Nematode development is generally most rapid within an optimal soil temperature range of 70 to 800F.

Symptoms

Typical symptoms of nematode injury can involve both aboveground and below ground plant parts.  Foliar symptoms of nematode infestation of roots generally involve stunting and general unthriftiness, premature wilting and slow recovery to improved soil moisture conditions, leaf chlorosis (yellowing) and other symptoms characteristic of nutrient deficiency.  An increased rate of ethylene production, thought to be largely responsible for symptom expression in tomato, has been shown to be closely associated with rootknot nematode root infection and gall formation.  Plants exhibiting stunted or decline symptoms usually occur in patches of variable growth rather than as a overall decline of plants within an entire field.

The time in which symptoms of plant injury occur is related to nematode population density, crop susceptibility, and prevailing environmental conditions.  For example, under heavy nematode infestation, crop seedlings or transplants may fail to develop, maintaining a stunted condition, or die, causing poor or patchy stand development.  Under less severe infestation levels, symptom expression may be delayed until later in the crop season after a number of nematode reproductive cycles have been completed on the crop.  In this case aboveground symptoms will not always be readily apparent early within crop development, but with time and reduction in root system size and function, symptoms become more pronounced and diagnostic.

Root symptoms induced by sting or rootknot nematodes can oftentimes be as specific as aboveground symptoms.  Sting nematode can be very injurious, causing infected plants to form a tight mat of short roots, assuming a swollen appearance.  New root initials generally are killed by heavy infestations of the sting nematode, a symptom reminiscent of fertilizer salt burn.  Root symptoms induced by rootknot cause swollen areas (galls) on the roots of infected plants.  Gall size may range from a few spherical swellings to extensive areas of elongated, convoluted, tumorous swellings which result from exposure to multiple and repeated infections.  Symptoms of root galling can in most cases provide positive diagnostic confirmation of nematode presence, infection severity, and potential for crop damage.

Damage

For most crop and nematode combinations the damage caused by nematodes has not been accurately determined.  Most vegetable crops produced in Florida are susceptible to nematode injury, particularly by rootknot and sting nematodes.  Plant symptoms and yield reductions are often directly related to preplant infestation levels in soil and to other environmental stresses imposed upon the plant during crop growth.  As infestation levels increase so then does the amount of damage and yield loss.  In general, the mere presence of rootknot or sting nematodes suggests a potentially serious problem, particularly on sandy ground during the fall when soil temperatures favor high levels of nematode activity.  At very high levels, typical of those which might occur under double cropping, plants may be killed.  Older transplants, unlike direct seed, may tolerate higher initial population levels without incurring a significant a yield loss.

Field Diagnosis and Sampling

Because of their microscopic size and irregular field distribution, soil and root tissue samples are usually required to determine whether nematodes are causing poor crop growth or to determine the need for nematode management.  For nematodes, sampling and management is a preplant or postharvest consideration because if a problem develops in a newly planted crop there are currently no postplant corrective measures available to rectify the problem completely once established.  Nematode density and distribution within a field must therefore be accurately determined before planting, to guarantee that a representative sample is collected from the field. Nematode species identification is currently only of practical value when rotation schemes or resistant varieties are available for nematode management.  This information must then be coupled with some estimate of the expected damage to formulate an appropriate nematode control strategy.

Advisory or Predictive Sample:  Samples taken to predict the risk of nematode injury to a newly planted crop must be taken well in advance of planting to allow for sample analysis and treatment periods if so required.  For best results, sample for nematodes at the end of the growing season, before crop destruction, when nematodes are most numerous and easiest to detect.  Collect soil and root samples from 10 to 20 field locations using a cylindrical sampling tube, or if unavailable, a trowel or shovel. Since most species of nematodes are concentrated in the crop rooting zone, samples should be collected to a soil depth of 6 to 10 inches.  Sample in a regular pattern over the area, emphasizing removal of samples across rows rather than along rows.  One sample should represent no more than 10 acres for relatively low-value crops and no more than 5 acres for high-value crops.  Fields which have different crops (or varieties) during the past season or which have obvious differences either in soil type or previous history of cropping problems should be sampled separately.  Sample only when soil moisture is appropriate for working the field, avoiding extremely dry or wet soil conditions.

Diagnostics on Established Plants: roots and soil cores should be removed to a depth of 6 to 10 inches from 10 to 20 suspect plants.  Avoid dead or dying plants, since dead or decomposing roots will often harbor few nematodes.  For seedlings or young transplants, excavation of individual plants may be required to insure sufficient quantities of infested roots and soil.  Submission of additional samples from adjacent areas of good growth should also be considered for comparative purposes.
For either type of sample, once all soil cores or samples are collected, the entire sample should then be mixed thoroughly but carefully, and a 1 to 2 pint sub sample removed to an appropriately labeled plastic bag.  Remember to include sufficient feeder roots.  The plastic bag will prevent drying of the sample and guarantee an intact sample upon arrival at the laboratory.  Never subject the sample(s) to overheating, freezing, drying, or to prolonged periods of direct sunlight.  Samples should always be submitted immediately to a commercial laboratory or to the University of Florida Nematode Assay Laboratory for analysis.  If sample submission is delayed, then temporary refrigerated storage at temperatures of 40 to 600F is recommended.

Recognizing that the rootknot nematode causes the formation of large swollen areas or galls on the root systems of susceptible crops, relative population levels and field distribution of this nematode can be largely determined by simple examination of the crop root system for root gall severity.  Root gall severity is a simple measure of the proportion of the root system which is galled.  Immediately after final harvest, a sufficient number of plants should be carefully removed from soil and examined to characterize the nature and extent of the problem within the field.  In general, soil population levels increase with root gall severity.  This form of sampling can in many cases provide immediate confirmation of a nematode problem and allows mapping of current field infestation.  As inferred previously, the detection of any level of root galling usually suggests a nematode problem for planting a susceptible crop, particularly within the immediate areas from which the galled plant(s) were recovered.

General Management Considerations

Currently nematode management considerations include crop rotation of less susceptible crops or resistant varieties, cultural and tillage practices, use of transplants, and preplant nematicide treatments.  Where practical, these practices are generally integrated into the summer or winter "off-season" cropping sequence.  It should be recognized that not all land management and cultural control practices are equally effective in controlling plant parasitic nematodes and varying degrees of nematode control should be expected.  These methods, unlike other chemical methods, tend to reduce nematode populations gradually over time.  Farm specific conditions, such as soil type, temperature, moisture, can be very important in determining whether different cultural practices can be effectively utilized for nematode management.

Dr Joe Noling
University of Florida
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EPA Findings
The EPA finds that most malathion uses do not trigger health concerns. Malathion, an organophosphate insecticide, is registered for use on dozens of agricultural crops and for many residential uses.  It is also used for mosquito control and medfly eradication.

There has been some concern about malathion as a carcinogen, but EPA considers current evidence unreliable.  The Agency classifies malathion as "suggestive of carcinogenicity but insufficient to assess human carcinogenic potential."

Some risks have raised EPA concern: handler exposure during residential application and toddler exposure following application.  Increased requirements for personal protective equipment and engineering controls are expected to mitigate applicator risks.  Additionally, EPA is likely to push for containers that are less likely to break.

The Agency also has some concern about environmental risks for bees, birds, some mammals, and fish.  It is expected that buffers, lower application rates, fewer applications, etc. will mitigate environmental risks.

The Georgia Pest Management Newsletter
December 2000
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Organic Info Sources
Appropriate Technology Transfer for Rural Areas (ATTRA) program maintains an extensive Web site on organic plug and transplant production at http://www.attra.org/attra/pub/plugs.html.  The site lists many resources, as well as recipes for organic media mixes.  Or contact ATTRA at P.O. Box 3657, Fayetteville, AR 72702;  800-346-9140; fax 501-442-9842.

Growing for Market is a monthly newsletter for market growers that covers all phases of small-scale and organic production and marketing.  You can reach the editor, Lynn Byczynski at PO. Box 3747, Lawrence, KS 66046; 800-307-8949;  http://www.growingformarket.com.

The Organic Trade Association (OTA) is an industry clearing house for information and an advocate for organic practices.  Contact OTA at 74 Fairview St., PO. Box 547, Greenfield, MA 01302; 413-774-7511; http:// www.ota.com.

Veteran grower Jay Martin recommends The New Organic Grower, by Eliot Coleman.  It's put out by Chelsea Green Publishing, P.O. Box 428, Gates/Briggs Building, #205, White River Junction, VT 05001; 800-639-4099; http://www.chelseagreen.com.

Florida Grower
November 2000
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Tomato Juice Fights Pneumonia
Scientists are working hard to create a not-too-distant future where tomatoes may cure pneumonia, potatoes prevent diarrhea, and corn enhances immune systems.  Some of those scientists are now working to apply the tools of biotechnology to introduce proteins into plants that can be used to fight human viruses capable of causing pneumonia, cholera, and tuberculosis.

Far-fetched?  Not for a researcher at the University of Illinois, Champaign-Urbana, where Professor of Plant Genetics Shuyler Korban works to develop a vaccine in the form of tomato juice capable of inoculating individuals susceptible to the virus RSB and the pneumonia it can cause.  Made from genetically modified tomatoes, Korban hopes to have the vaccine ready for human consumption by 2005.  But don't look for it on a supermarket shelf, the vaccine will be made from prescription tomatoes.

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Pesticide Potpourri
Registration and Tolerance Actions

Bayer has added use on citrus and celery to their Admire (imidacloprid) label.

Due to the high cost for re-registration, Novartis will not support indoor applications of Diazinon which will eliminate uses in greenhouses, residential settings, commercial buildings, hospitals, schools, museums, sport facilities, stores and warehouses.

Due to the high cost of re-registration, Iquinosa has requested EPA to delete from their Lindane label use on celery, collards, kale, kohlrabi, mustard greens, and Swiss chard.  Unless withdrawn the deletions will be effective 2/4/2000.

Aventis has added use by chemigation on potatoes to their Phaser (endosulfan) label.

Zeneca has added usage on tomatoes and tomatillo to control various insects such as loopers, cutworms, hornworms, flea hoppers, aphids and whiteflies to their label for Warrior (lambda cyhalothrin).

Rohm & Haas has added use on garlic, shallots and gourds to their Dithane M-45 label.

Due to registration costs BASF will delete several uses from their vinclozolin product labels.  They will delete onions and raspberries from the label with sale of the product for these crops until 01/01/2000 and the last day of usage is 09/01/2000.  On kiwi fruit and Belgium endive which will be deleted from the label by 12/31/2001, the last day for sale is 12/31/2002 and the last day for usage is 11/30/2003.  On ornamentals the last day for sale is 07/15/2000 and the last day for use is 09/01/2001.  On lettuce and succulent beans the last day for sale is 07/15/2005 and the last day for usage is 09/30/2005.
(Agrichemical News, October 15, 2000)

Section 18 Emergency Exemption

EPA, under provisions of Section 18 of FIFRA, has issued a specific exemption for the use of Quadris Flowable Fungicide (azoxystrobin) for control of anthracnose on strawberries.  The exemption will expire on May 31, 2001. Section 18 labeling must be in the possession of the user at the time of pesticide application.

EPA's draft final rule on plant pesticides (now called plant incorporated protectants) was sent to USDA for 30 day prepublication review, September 15.

FQPA SPOTLIGHT
September 29, 2000

The United States District Court in Washington granted a summary judgement to the Food and Drug Administration (FDA) dismissing a lawsuit filed by the Alliance for Bio-Integrity, an opponent of biotechnology.  The judge upheld FDA policy on genetically modified food and rejected the Alliance for Bio-Integrity's attack that the lack of labeling and mandatory safety testing violated safety laws.  The decision reaffirms the FDA's 1992 policy statement that said genetically modified foods were generally recognized as safe and would not be regulated as food additives.  This policy also said labeling of such foods was not required because genetic engineering did not change food in any material way.

American Crop Protection Association
October 4, 2000
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Move Over Habanero

SCIENTISTS in India claim they have a chili variety that literally smokes the famed "world's hottest!" Mexican habanero pepper.

"Tests by a team of experts here have confirmed that Naga Jolokia, a specialty from the northeast, is now the world's hottest chili,"  S.C. Das told the Associated Press. Das is the deputy director of the Defense Research Laboratory in the garrison town of Tezpur.

He said that the Naga Jolokia, or Capsicum frutescens, surpasses the tongue-burning ability of the Red Savina Habanero, a Mexican chili that has been known as the world's hottest.  Das claims the Naga Jolokia measured 855 Scoville units, compared to 577 for the Habanero in tests.

Vegetable Grower
November 2000
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EPA Says Bt is OK
AN EPA preliminary draft risk assessment for Bt corn, cotton, and potato plant pesticides offers a major boost to proponents of the technology.

The report states that Bt crops offer the advantages of higher yields, reduced use of farm chemicals, and lower levels of ground-water contamination.

"EPA believes that significant benefits accrue to growers, the public, and the environment from the availability and use of certain Bt plant pesticides," the report said. "For ... Bt potatoes, the major benefits predicted were a reduction in the use of chemical pesticides."

The report also found that after five years of use by U.S. growers, there has been no incidence of insect resistance to Bt corn, cotton, or potato plants.

Vegetable Grower
November 2000
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Federal News
The EPA is generating considerable interest with an upcoming decision regarding an anti microbial wash.  Proctor & Gamble hopes to market - Fit Fruit and Vegetable Rinse.  The company claims that the product will kill germs as well as removing pesticides, wax, dirt, etc.  The EPA gained jurisdiction when the company claimed the product would control pests, i.e., bacteria.  The claims of pesticide, wax, and dirt removal are not covered under EPA mandates.  Antibacterial products of this nature are a new area for the Agency.

If this product is approved, look for similar items to follow.  Society has become so concerned about bacteria that some scientists are concerned that we may be compromising development of the human immune system.

Pesticide & Environmental News, 9-7-00
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Vegetable Producers at Risk
Vegetable producers are at particular risk from FQPA decisions because many of the concerns focus on produce; additionally, vegetable crops represent a relatively small financial incentive for pesticide companies.  A lack of knowledge also exacerbates the problem.  In many cases, EPA has little or no information concerning production of vegetables.  As a result, Agency decisions may be based upon unreliable assumptions.

The Georgia Pest Management Newsletter
December 2000
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Health and the Environment
In the public mind, pesticides are often linked with cancer, but the facts do not support this supposition.  According to the Georgia Cancer Data Report, tobacco accounts for 30% of cancer deaths.  Another third are related to diet, nutrition, and lack of exercise.  The highlights of the Georgia report appeared in the October issue of Georgia Epidemiology: pesticides are not mentioned.

Many people are up in arms about pesticide and cancer, but their efforts may be misplaced.  Only about 20% of Georgian adults consumed five or more fruits or vegetables per day; less than 1/3 have regular exercise.  We should not waste resources on pesticides that would be better used elsewhere.

To obtain a copy of the Georgia Cancer Data Report, visit http://www.ph.dhr.state.ga.us/

The Georgia Pest Management Newsletter
December 2000
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On the Lighter Side
A farmer got pulled over by a state trooper for speeding, and the trooper started to lecture the farmer about his speed, and in general began to throw his weight around to try to make the farmer uncomfortable.  Finally, the trooper got around to writing out the ticket, and as he was doing that he kept swatting at some flies that were buzzing around his head.

The farmer said, "Having some problems with circle flies there, are ya?"

The trooper stopped writing the ticket and said, "Well yeah, if that's what they are. I never heard of circle flies."

So the farmer says, "Well, circle flies are common on farms.  See, they're called circle flies because they're almost always found circling around the back end of a horse."

The trooper says, "Oh," and goes back to writing the ticket.  Then after a minute he stops and says, "Hey wait a minute, are you trying to call me a horse's ass?"

The farmer says, "Oh no, officer.  I have too much respect for law enforcement and police officers to even think about calling you a horse's ass."

The trooper says, "Well, that's a good thing," and goes back to writing the ticket.

After a long pause, the farmer says, "Hard to fool them flies though."
 
DRIVING STYLES
Chicago: One hand on wheel, one hand on horn.

New York: One hand on wheel, one finger out window.

New Jersey: One hand on wheel, one finger out window, cutting across all lanes of traffic.

Ohio, but driving in Florida: Both hands on wheel, eyes shut, both feet on brake, quivering in terror.

West Virginia: Four-wheel drive pickup truck, shotgun mounted in rear window, beer cans on floor, squirrel tails attached to antenna.

Florida: Two hands gripping wheel, blue hair barely visible above window level, driving 35 on the Interstate in the left lane with the left blinker on.

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