SOUTH FLORIDA VEGETABLE PEST AND DISEASE...
Transcript of SOUTH FLORIDA VEGETABLE PEST AND DISEASE...
Palm Beach County Extension 559 N. Military Trail WPB, Florida 3315 Phone (561) 233-1700
May 8, 2017
Most of South Florida received some much-needed rain over the past couple of weeks with reports
ranging from of less than an inch to over 7 inches depending on the location. Heavy rains in some areas
damaged crops resulting in losses. Growers reported hail in a few places.
Temperatures have been relatively mild with daytime highs ranging from the upper 70’s to low 90’s and
night time temps ranging from the 50’s to the 60’s. Frontal passage over the past weekend bought a
refreshing but short lived cool down with overnight lows in the 50’s.
FAWN Weather Summary
Date Air Temp °F Rainfall Ave Relative Humidity ET (Inches/Day)
Min Max (Inches) (Percent) (Average)
Balm
4/11 – 5/8/17 50.11 95.65 1.09 70 0.16
Belle Glade
4/11 – 5/8/17 54.61 90.99 5.45 82 0.16
Clewiston
4/11 – 5/8/17 52.86 92.32 2.39 76 0.16
Ft Lauderdale
4/11 – 5/8/17 60.24 87.46 7.50 75 0.16
Homestead
4/11 – 5/8/17 55.58 89.89 3.44 77 0.15
Immokalee
4/11 – 5/8/17 50.70 95.54 4.51 77 0.15
Okeechobee
4/11 – 5/8/17 45.91 94.91 2.75 77 0.16
Wellington
4/11 – 5/8/17 55.94 86.56 2.45 75 0.16
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SOUTH FLORIDA
VEGETABLE PEST AND DISEASE
HOTLINE
Palm
Beach
County
An ugly season is rapidly coming to an ugly end in much of south Florida, in some cases prematurely, due
to heavy insect pressure and hot weather. Whiteflies, thrips, weevils and viruses are taking their toll on
many crops. A variety of crops are coming to market including cabbage, collards, cucumber, eggplant, escarole,
green beans, herbs, kale, mustard, peppers, potatoes, radishes, squash, sweet corn, Swiss chard, tomato,
watermelon and a variety of specialty items.
The National Weather Service forecast indicates that surface high pressure will remain in place across
Florida through much of the upcoming week, leading to an extended period of dry weather and mostly
sunny skies. Generally light winds are expected across South Florida outside of local sea breezes during the
afternoon and early evening hours. Stray light shower may occur along with a slight increase in cloud cover in
conjunction with the sea breeze development each afternoon The next appreciable rain chances may come next
weekend as a weak frontal system approaches.
After a relatively cool start to the week, temperatures will increase moderately through the remainder of
the week back to above normal, with highs in the mid-80s to lower 90s, and lows ranging from the mid-
60s to mid-70s.
For additional information, visit the National Weather Service in Miami website at http://www.srh.noaa.gov/mfl/newpage/index.html
Insects
Whiteflies
Reports indicate that whitefly numbers in the Manatee Ruskin area are increasing along with TYLCV in
many fields. Respondents indicate that sprays targeted at spider mites are helping suppress whiteflies in some
places.
Around Immokalee, growers and scouts report that whiteflies are everywhere and have increased in
number over the past few weeks in many places. Whiteflies are causing issues with sooty mold in several
crops and irregular ripening has been an issue and resulted in losses in some fields. Whitefly vectored viruses
are widespread and severe in some cases causing losses in tomato and watermelon and other cucurbits.
Respondents in Miami Dade County indicate that whitefly remains common on eggplant, squash and
oriental vegetables.
In the Palm Beach area, whiteflies are high in tomato, squash and eggplant, and have become a problem
especially in Palm Beach County.
Whiteflies are causing problems around Homestead with bean golden mosaic virus becoming common in
green beans.
Reports indicate that TYLCV is moving in places especially where growers are not using TYLCV
resistant cultivars, and cucurbit leaf crumple virus has become widespread in watermelons and cucurbit
yellow stunting disorder virus is also becoming common in watermelon as well. Increasing incidence and
severity of vine decline (squash vein yellowing virus) is also being reported in watermelon. Some tomato fields
in SW Florida are also experiencing a high percentage of irregular ripening.
As noted above this spring is shaping up to be a bad season for whitefly and attendant problems
including virus in tomatoes and melons, silverleaf in squash and irregular ripening in tomato.
Irregular ripening is a physiological disorder unrelated to virus but caused by feeding of whitefly
nymphs, not adults. The threshold for irregular ripening is 1 nymph per 2 leaflets. Nymphs are best
monitored on the underside of the lower (5-7th node) leaves.
The whitefly situation has been exacerbated by a warm mild dry winter and the fact that many tomato
fields around South Florida have been abandoned after one pick due to low prices. In addition, due to
low prices growers have been reluctant to spray. Even though most of the abandoned acreage has been
sprayed with an herbicide, in many cases, there is still plenty of green living tissue to support whiteflies as well
as other pests and diseases. Some fields, have literally have clouds of whiteflies streaming out of them and
settling on nearby spring plantings. This situation is not playing out well for spring crops.
Field hygiene including rapid and timely crop destruction and clean up should be a high priority and
should be an integral part of the overall strategy for managing whitefly populations, TYLCV incidence,
and insecticide resistance. These practices will help reduce the onset of the initial infestation of whitefly,
regardless of biotype, and lower the initial infestation level during the cropping period.
Disrupt the virus-whitefly cycle in winter by creating as long a break in time and/or space as possible
between fall and spring crops, especially tomato, cucurbits and other crops where whitefly vectored
viruses are an issue.
Promptly and efficiently destroy all vegetable crops within 5 days of final harvest to decrease whitefly
numbers and sources of plant viruses like TYLCV.
Destroy old crops quickly and thoroughly after harvest, killing whiteflies and prevent re-growth.
Spray first with a tank mix of pyrethroid and malathion to kill whiteflies in the old crop. Use a contact
desiccant (“burn down”) herbicide in conjunction with a heavy application of oil (not less than 3 % emulsion)
and a non-ionic adjuvant to destroy crop plants and to kill whiteflies quickly.
Time burn down sprays to avoid crop destruction during windy periods, especially when prevailing
winds are blowing whiteflies toward adjacent plantings.
Treat spring plantings of tomato with a systemic insecticide in the transplant water. (Table 1). If on drip,
make a second soil application in 30 days using a systemic insecticide of different mode of action
Scout crops every week and apply insecticides as needed to maintain control. Target nymphs once the threat of
immigration from old crops has passed (Table 2).
Table 1: Systemic insecticides applied to soil for whitefly control
Common name Mode of Action Trade Names Rates
Imidacloprid 4A Various Check Label
Thiamethoxam 4A Platinum 75 SG 1.66 - 3.67
4A Venom 70%
Scorpion 35 SL
Certador 10%
5 - 7.5 oz/ac
9 -1 0.5 fl oz/ac
32.5 - 47.5 fl oz/ac
Flurpyradifuron 4D Sivanto 200 SL 21-28 fl oz/ac
Verimark 28 Verimark 18.7% 5-10 fl oz/ac
Table 2: Efficacy Ratings for Insecticides and Miticides on Tomato
Whiteflies Other pests controlled
MOA
Active
Ingredient Whiteflies
Southern
Armyworm
Spider
mites Stinkbugs Leafminer
4A dinotefuran E** G
4A imidacloprid E**
4A thiamethoxam E** G
4D flupyradifurone E**
23 spiromesifen E† E
23 spirotetramat E† G
7C pyriproxyfen E†
28 cyantraniliprole E** E E
1B malathion G*
3A beta-cyfluthrin G* F G
3A bifenthrin G* G
3A esfenvalerate G* G
3A fenpropathrin G* F F
3A
lambda
cyhalothrin G* F
3A permethrin G* G
3A
zeta-
cypermethrin G* G F
4A acetamiprid G
9 pymetrozine G†
16 buprofezin G†
21 A fenpyroxiamate G G
4A clothianidin F**
- horticultural
mineral oil F† G
- Azadiractin F†
- Soap,
insecticidal F†
* OP+Pyrethroids tank mix.
** Most Effective as a drench.
† Effective primarily against nymphs
Check labels before using any pesticide.
For more whitefly management tips – see:
Recommendations for Management of Whiteflies, Whitefly-Transmitted Viruses, and Insecticide
Resistance for Production of Cucurbit Crops in Florida - http://edis.ifas.ufl.edu/in871
Management of Whiteflies, Whitefly-Vectored Plant Virus, and Insecticide Resistance for Vegetable
Production in Southern Florida - http://edis.ifas.ufl.edu/in695
Spider mites
With hot dry conditions, spider mites are flaring up in several locations around South Florida on
cucurbits, eggplant and tomatoes.
Respondents in the Manatee Ruskin area indicate that growers are battling with Spidermites in tomato
and note they are literally killing some plants in worse affected locations.
Pepper Weevil
Pepper weevils are widespread in pepper fields around Southwest Florida and numbers are building as
the season nears an end. Some growers report having abandoned fields where weevils have gotten out of
control and many pepper fields no longer have buds, or growing points from weevil damage and some eggplant
fields are getting hammered with significant bud damage as well.
Reports from East Coast production areas indicate that pepper weevil numbers are high to extremely
high in all counties and will curtail extended production in some older pepper fields. Weevil are high in
eggs and requiring frequent sprays to protect fruit.
Scouting is importance as with other pests to detect infestations at an early stage. In the absence of Vydate,
growers may want to look at Exirel, Actara, Rimon, Dimilin and the pyrethroids to knock down adults. Growers
should be aware that you cannot spray your way out of this problem but need to take a pro-active IPM approach
throughout the season including good sanitation and destruction of old fields and separation of planting in time
and space with a crop-free period between fall and spring plantings where practicable.
Worms
Around Southwest Florida, there are a few armyworms around, and loopers are increasing in melons and
tomatoes. Reports indicate that diamondback moths are increasing and causing some problems in crucifers.
On the East Coast, diamond back moth larvae continue to cause damage to crucifers.
Reports from the Ruskin area indicate that worms are still an issue, with pinworm, beet armyworm,
loopers and loopers attacking tomatoes and other crops. Diamondback moths remain active in crucifers and
have reached high numbers in some fields.
Around Homestead, army worms are active in remaining crops.
Respondents in the Glades indicate that armyworms are spotty in corn as the crop moves away from the
Lake and pressure low to very low in most places. Southern armyworms are reportedly causing some issues
in other vegetables on the muck.
Thrips
Growers and scouts report a significant increase in thrips pressure in most areas.
On the East Coast, respondents indicate thrips are increasing and have built up in the last of the peppers
and tomatoes in Palm Beach County resulting in some fruit damage. Thrips from range from almost none
to high in tomato, pepper and eggplant depending on location. Numbers are generally higher around Palm
Beach and lower in Martin and St Lucie with some exceptions. Scouts report they are mostly western flower
thrips with a sprinkling of Thrips palmi.
Melon thrips continue to cause problems around Miami Dade County. Reports indicate numbers are high
in eggplants and adults are being found in squash, cucumber, beans and okra as well.
Scouts continue to report finding a few thrips vectored groundnut ringspot virus and tomato chlorotic
spot virus infected plants here and there around South Florida but.
Around Southwest Florida, Thrips palmi are also becoming serious problems in several pepper fields, as
well as some eggplants and they are also starting to bronze some leaves in some watermelon fields.
Growers report that where present they have been a challenge to control and some crops have been lost.
Around Hillsborough County, thrips numbers remain fairly low in most places.
Growers and scouts should learn to identify thrips species and take a soft IPM approach to reduce
numbers and favor beneficial insects such as minute pirate bug which have been shown to help control
populations.
Radiant, Movento, Torac, Exirel and Requiem in rotation can be used to manage thrips. Addition of non-
ionic surfactant in tank mix to will increase effectiveness on insecticides.
Aphids
Around South Florida aphids are around but are mostly insignificant compared to other insect issues.
Growers and scouts in Southwest Florida, report that aphids are patchy and have required control in
several places especially in organic crops.
In the EAA, aphids are still an issue in sweet corn resulting in honey dew and sooty mold on the ears as
the corn nears maturity. They are present in low numbers throughout the growing cycle, but tend to flare up
at the end. The numbers on the flags and silks are low while most the colonies (which remain small) are located
on the underside of leaves up and down the plant. Aphids are also showing up in leafy greens and brassicas. as
well.
Lesser cornstalk borer
Around the Glades, lesser cornstalk borer trap counts have dropped significantly in recent days.
Broad Mites
Around Southwest Florida, broad mites remain widely present and persistent in pepper and eggplant.
Growers and scouts on the East Coast report a downward trend in broad mite pressure apart from some
hotspots where they remain a problem.
Silkfly
In the EAA, silk flies continue to be an issue in sweet corn with the highest numbers being around the
lake. Levels of both adults and immatures can be characterized as low.
Growers should scout corn fields carefully for silk fly infestation. Certis Bait pellets have shown significant
reduction of adults and silkfly damage on corn ears. Pyrethroids can also be used to reduce silk fly adults.
Leafminer
Leafminers appear to be declining in most locations although they are still around and causing some
problems in the Manatee Ruskin area.
Diseases
Diseases caused by fungal and bacterial pathogens have been relatively low but this may change because
of recent rains.
Late Blight
Growers and scouts in SW Florida reported a flare up of late blight in a few locations around Southwest
Florida in conjunction with recent rains.
Bacterial Spot
On the East Coast, bacterial spot is low but growers should keep an eye on non- resistant pepper and
tomato after recent rains.
Low levels of bacterial spot are present in the Manatee Ruskin area.
Target Spot
Mostly low levels of target spot are reported around the South Florida
Early Blight
Alternaria is increasing on tomato around south Florida. Some of this is associated with leafminer damage.
Low levels of early blight have also been reported around Manatee County.
Powdery Mildew
Growers and scouts report powdery mildew is starting to increase in some watermelons and is also
increasing in squash around Southwest Florida.
Powdery mildew is present in cucumber and squash around Palm Beach County and is also starting to
show up on some Cubanelle pepper as well.
Growers and scouts indicate that powdery mildew is widespread in cucurbits around Homestead
including squash and bitter melon.
Dill producers are reporting some issues with powdery mildew on dill.
Growers are getting good control with products like Fontelis, Quintec, Torino, and Rally.
Downy Mildew
On the East Coast, downy mildew has jumped on mature squash in recent days.
Around Immokalee, downy mildew is active in cucumbers and starting up in some watermelons and in
cantaloupe.
Downy mildew is also present on squash in Homestead.
Downy mildew continues to plague basil producers and is increasing with cooler humid nights and foggy
conditions.
Phytophthora
Reports from Palm Beach County indicate Phytophthora is causing problems in some older pepper in
areas where it is traditional a problem. It is also hitting some eggplant where fruit are becoming infected on
the ground as well as some double crop squash.
Phytophthora is causing some problems around Homestead and in Devils Garden following recent heavy
rains.
Tomato Chlorotic Spot Virus
Tomato chlorotic spot virus (TCSV) is mostly low and stable but can be found in all counties in South
Florida.
Early symptoms of infection are difficult to diagnose. In young infected plants the characteristic symptoms
consist of inward cupping of leaves and leaves that develop a bronze cast followed by dark necrotic spots.
Tomato chlorotic spot virus causes necrosis in tomato leaves and stems, and causes ringspots and other
deformations of the fruit. The symptoms are nearly identical to those of groundnut ringspot virus and
laboratory diagnosis is necessary to distinguish on from the other.
Common purslane has been identified as an alternate host, so growers should pay attention to weed
management.
The use of virus-free transplants, insecticides to control thrips, rouging infected plants, SAR elicitors
such as Actigard, and UV-reflective mulch will likely be effective managing TCSV.
Tomato Yellow Leaf Curl
A few scattered TYLCV infected plants have been reported in tomatoes in all production areas around
South Florida.
On the East Coast TYLC is increasing in some older tomato.
TYLCV is present and increasing around Manatee County.
TYLCV is increasing quickly in many fields around SW Florida and has reached infection rates have
surpassed 50% or more in some older fields and is showing up more frequently in younger fields.
With the huge number of whitefly moving off abandoned fields, lack of cold weather and very high
whitefly counts being reported in many fields, the situation is ripe for virus to explode in the spring crop. Growers would be advised to rapidly and efficiently destroy abandoned fields and aggressively target whiteflies
in younger plantings.
Watermelon mosaic virus
Growers in few locations around Southwest Florida are experiencing problems with widespread mosaic
in melons and squash at levels higher than we have seen for the past few years.
Growers and scouts in Homestead report mosaic virus is common in squash.
Cucurbit leaf crumple virus
Around Homestead, cucurbit leaf crumple virus is widely present in squash.
In Southwest Florida, cucurbit crumple leaf virus is widely present and increasing in watermelons.
Cucurbit yellow stunting disorder virus
Cucurbit yellow stunting disorder virus is now becoming more common in watermelons around South
Florida.
Vine Decline
Scouts report that squash vein yellowing virus (SqVYV) (aka vine decline) is present in several
watermelon fields around Southwest Florida.
Cucurbit Virus Advisory
Cucurbit crumple leaf virus (CuLCrV) along with squash vein yellowing virus (SqVYV) (aka vine
decline) and Cucurbit yellow stunting disorder virus (CYSDV) are all whitefly transmitted viruses which
have appeared relatively recently in Florida. Scouts are already finding all three viruses in watermelon
around SW Florida.
The fact that watermelon growers around SW Florida saw major issues with CYSDV last spring and a
re-emergence of vine decline (SqVYV) after several relatively quiet years, coupled with the fact that
CuLCrV is widely present at low levels in squash and water melons this past fall suggests growers should
be alert this spring and practice aggressive scouting and whitefly management in these crops.
We have had another relatively mild winter to date without any cold weather to take out the wild
cucurbit hosts (balsam apple, bur cucumber etc.) of these viruses so there is high probability that these
viruses could over winter and be ready to jump into spring plantings.
In addition, we are seeing very high whitefly numbers around SW Florida. Even though these are
primarily moving out of tomato (a non-host), they are hunger and could acquire one or more of these
viruses while moving around before settling down in a squash or melon field.
As you may know Georgia watermelon producers experienced major issues with cucurbit crumple leaf
virus this fall. Crumple leaf also infects beans and caused major issues in beans as well.
As a result, we are seeing unprecedented levels of these whitefly vectored viruses in spring watermelon
production (and other cucurbits) in South Florida.
Cucurbit Virus Update
Three whitefly-transmitted viruses are currently known to infect watermelon, squash and other cucurbits
in Florida: Squash vein yellowing virus (SqVYV), Cucurbit leaf crumple virus (CuLCrV) and Cucurbit
yellow stunting disorder virus (CYSDV). The most devastating of these is SqVYV, which is the cause of
viral watermelon vine decline first described in 2003 in Florida. CuLCrV and CYSDV were more recently
introduced to Florida, and have generally been more common than SqVYV until the past two winter growing
seasons.
To further complicate symptoms observed, several aphid-transmitted viruses including Papaya ringspot
virus (PRSV) are also regularly detected in Florida cucurbit crops. CuLCrV, CYSDV and PRSV have
predominated in many locations but SqVYV (and viral watermelon vine decline) has once again been detected
in all major peninsular watermelon production areas during the current growing season.
Initial symptoms of SqVYV infection in watermelon are petiole necrosis and leaf wilt (often near vine tips) that
rapidly progress to plant collapse. Watermelon fruit develop internal discoloration and necrosis in the rind and
degradation of the flesh. Often these symptoms appear just before harvest.
Cucurbit crops and weeds are the only reported hosts for SqVYV, and many only display mild vein
yellowing symptoms on leaves. Yellow summer squash is perhaps most affected because fruits develop green
lines that run lengthwise on the yellow skin. A limited number of vining cucurbits other than watermelon
develop vine decline symptoms but these species are generally not important crops in Florida.
In contrast, CuLCrV or CYSDV infection leads to chlorosis (yellowing) of watermelon leaves.
For CuLCrV, this is most often a bright yellow chlorosis (like Tomato yellow leaf curl virus in tomato)
that appears near the tip of the vines. This is often accompanied by severe distortion of the leaves (the
“crumple” symptom for which the virus is named).
For CYSDV, this is most often a pale-yellow chlorosis that appears in the older leaves near the crown of
the plant.
In addition to cucurbits in Florida, CuLCrV has been detected in green bean and CYSDV has been
detected in pigweed.
Symptoms of PRSV and other aphid-transmitted viruses commonly appear on watermelon and squash
leaves as a mosaic of light and dark green. Sometimes this may be accompanied by blistering of the leaves.
The major economic impact of SqVYV infection of watermelon is from the reduction in fruit weight and
quality. Fruit rind and flesh colors are altered from those of non-infected plants often rendering them
unmarketable. Fruit sucrose content is reduced and fruit acid content is increased. The only other documented
fruit impact of SqVYV is on yellow summer squash as noted above.
Cucurbit weeds including balsam apple (Momordica charantia), creeping cucumber (Melothria pendula)
and smellmelon (Cucumis melo var. dudaim) serve as reservoirs for these viruses and the whitefly and
aphid vectors. Although symptoms are not always obvious, cucurbit weed management remains an important
part of cucurbit virus management plans.
There is presently no genetic resistance to whitefly-transmitted viruses in commercially-available
cucurbit cultivars. Management tactics presently focus on managing the vector. In addition to controlling
cucurbit weeds, prompt destruction of harvested fields is key to reducing the viral source (inoculum). It is
recommended that crops be sprayed with a fast-acting herbicide such as gramoxone combined with a crop oil to
reduce migration of viruliferous whiteflies from the field. Early season protection of the crop is crucial.
Metalized plastic mulches have a repellant effect on whiteflies as well as aphids and thrips, and can
reduce early infections. Black or white plastic mulches with a central metalized band are also available to help
protect young crops.
Soil and drip applied systemic insecticides are important tools for providing early and mid-season
protection from whiteflies. Insecticides with systemic activity for whitefly management include the
neonicotinoids Admire (imidacloprid), Platinum (thiamethoxam) and Venom (dinotefuran), the butenolide
Sivanto Prime (flupyradifurone) and the diamide Verimark/Exirel (cyazypyr). Most of these insecticides have
pollinator protection warning instructions on the label. Soil application of insecticides and nighttime application
of foliar insecticides may reduce, but will not eliminate, impacts on pollinators. The insect growth regulators
Knack (pyriproxifen) and Courier (buprofezin) will reduce the number of viable whitefly eggs and prevent
nymphs from completing development. Biopesticides including insecticidal soap (M-Pede) and Beauvaria
bassiana products (Botanigard, Mycotrol) can help reduce whitefly numbers when used repeatedly.
A treatment window of 4-5 weeks should be used to plan insecticide rotations for management of
whiteflies in cucurbits. The purpose of the treatment window approach is to avoid applying the same mode of
action to successive generations of the same pest. For example, cucurbits could be treated at planting with
Verimark, followed by a foliar application of Exirel a few weeks later, before blooms are abundant. A
neonicotinoid could be applied through the drip at week five followed by a foliar application of Sivanto, which
has limited contact impact on pollinators. This approach would confine the use of diamides to the first five-
week treatment window, and the use of neonicotinoids and butenolides, which have the same mode of action, to
the second five-week treatment window.
Always read and follow label instructions when using insecticides.
This information was provided by Scott Adkins (USDA ARS Ft Pierce) and Hugh Smith (University of
Florida, Gulf Coast Research and Education Center).
See Recommendations for Management of Whiteflies, Whitefly-Transmitted Viruses, and Insecticide
Resistance for Production of Cucurbit Crops in Florida - http://edis.ifas.ufl.edu/in871
Efficacy Table for Single Mode of Action Insecticides and Miticides Labeled for Cucurbit Vegetables in
Florida - https://www.scribd.com/document/341391847/Efficacy-Insecticides-Cucurbits-003
Corn leaf blight
Growers and scouts in the EAA are seeing low levels of northern corn leaf blight in sweet corn.
Northern corn leaf blight caused by the fungus Exserohilum turcicum.
Initial symptoms of the NCLB include yellow spots that develop on the foliage. These enlarge to form tan
or straw-colored dead areas about 4 to 6 inches long and one half inch wide. NCLB produces a long, elliptical
lesion, while those of southern corn leaf spot tend to be oblong and much smaller than those produced by
NCLB.
Lesions caused by southern corn leaf blight are much smaller (up to ½ inch wide and 1-inch-long) than
those caused by northern corn leaf blight. SCLB blight lesions are also lighter in color (light tan to brown),
and have parallel sides rather than the tapering sides of lesions caused by E. turcicum.
Northern corn leaf blight, like southern corn leaf blight, moves from the lower canopy to the upper
canopy. Fungal sporulation may be observed with a hand lens on foliar lesions following periods of high
humidity. When severe, lesions may become so numerous that they coalesce and turn the entire leaf necrotic.
Bean Rust
Reports from the Glades indicate that mostly low levels rust are becoming common in susceptible beans
varieties.
Initial signs of bean rust on common bean include fungal sori, seen as small white specks under the leaf
epidermis, and rust colored pustules. These pustules are found mainly on the underside of the leaf and are
often surrounded by a chlorotic ring.
Bean Golden Mosaic
Growers and scouts in Homestead report that bean golden mosaic virus is increasing in green beans
around the area.
News You Can Use
Sanitation, Sanitation, Sanitation...
Once again as we near the end of the deal, growers are reminded of the importance of sanitation in an integrated
pest management program. Disease and insects do not magically materialize to plague growers. Many require
a living host to carry them from one season to another. In fact, many of the problems that we are experiencing
this spring with pests like whiteflies and weevils can be partially attributed to the failure to promptly and
efficiently clean up fall crops setting the stage for problems this spring.
Field sanitation is one of the most important tactics in vegetable pest and disease management. One of the best
things that growers can do for themselves and their neighbors is to clean up crop residues promptly after
harvest. Sanitation is an important IPM technique that should not be over looked as an effective, preventative
tool against many vegetable pest and disease problems. Sanitation includes any practice that eradicates or
reduces the amount of pathogen inoculum, pests, or weed seeds present and thus helps reduce or eliminate
subsequent pest and disease problems.
Prompt crop destruction at the end of the season will immediately end the production of disease inoculum and
insects and eliminate the spread of diseases and pests to any other host plants in the vicinity. Downy and
powdery mildew on melons can spread via wind from older, diseased plants to plants in surrounding fields that
are still maturing. These diseases are obligate parasites. This means that they can only grow and multiply on
living host tissue. Some plant pathogens, such as the bacterium that causes bacterial spot of tomato and pepper,
are unable to survive for extended periods of time outside of the host tissue. Plowing or disking under infected
plant debris helps not only by covering up the inoculum but also speeds up the disintegration of plant tissue and
kills the pathogen. Good sanitation will help control several important vegetable pathogens.
Cull piles should not be neglected as several scouts over the past few years have reported that they have found
both insects and diseases such as TYLCV, late blight, whiteflies and others in volunteer plants springing up
around cull piles.
Soil tillage can destroy insects and expose them to birds and other predators. It can also speed the breakdown of
plant residues that harbor insects and plant pathogens. By either allowing the organic matter in a field to
decompose completely before you plant the next crop and /or allowing a fallow period between crops, you can
enhance the control of many insects and diseases.
Destruction of tomato vines will kill off white fly populations and eliminate transmission of the tomato yellow
leaf curl and other viruses to subsequent crops and eliminate inoculum from late blight and other fungal
diseases. This is particularly important in the case of TYLCV and other viruses, as sanitation, a crop-free
period, and whitefly/thrips control are the only tools currently available for the management of this disease. A
crop-free period is also considered a necessity for the control of several other important vegetable pests such as
pepper weevil, tomato pinworm, whitefly and thrips and is recommended for management of all vegetable
pests.
A little extra effort spent in cleaning up old fields at the end of the season may well prevent or reduce potential
problems next fall!
Summer weed management can be a challenge and will become increasingly important in the post- methyl
bromide era. Growers should check field margins to make sure that pest species are not building up there and
migrating out into cropping areas. Many insects over summer on weeds, so efforts to control them can be
profitable by reducing their movement into the crops next growing season.
Weeds are also known reservoirs of nematodes as well as several viral, fungal and bacterial pathogens. Weeds
and volunteers should be removed to prevent the survival and over-summering of pathogens that could serve as
inoculum reservoirs for the next crop. Techniques such as mowing off pepper should not be relied upon as this
often results in re-sprouts, which can harbor pests and disease problems over summer.
The use of cover crops and summer fallowing of fields are also effective tools in reducing weed populations that
can cause problems in the subsequent crop. The role of summer fallow in weed management is often
overlooked and again promises to become more important in the absence of methyl bromide as a component of
a comprehensive methyl bromide alternative strategy. Summer fallow keeps new weed seeds from being added
to the soil seed-bank. It also reduces the increases in asexual propagated plants such as nutsedge. Yellow
nutsedge can put out 70 new tubers (nuts) every two months. Keeping the weeds from propagating will reduce
the weed problems encountered during the next cropping season and help reduce insects and diseases that may
over summer in weedy fields.
Chemical fallowing is a twist on the traditional method of fallowing that depends on disking fields throughout
the summer period to reduce weed pressure in subsequent crops. One approach uses glyphosate to kill weeds
during the crop-free period. Note with some combinations of high use rates, heavy weed infestation, soil
fumigation, short plant back times and other factors growers have experienced carryover resulting in
phytotoxicity and plant damage in subsequent crops on sandy soils. In response to glyphosate resistant weeds,
many growers are tank mixing glyphosate with 2,4-D and other herbicides during the fallow period to pick up
escapes.
Cover crops planted prior to the main cash crop can improve soil fertility and provide a valuable source of
organic matter. They can also help suppress weeds and some soil pests, such as nematodes in some instances.
Sunn hemp seed is coming down and is about a dollar and a half per pound now; so, the recommended seeding
rate at 25-30 lb per acre costs only about $40 per acre, which is reasonable alternative when compared to the
labor and fuel costs to disk the land.
With new regulations for fumigants, building soil organic matter content with summer cover crops can help
provide credit which will allow reductions in the proposed required buffer zones requirements. For example, by
raising soil organic content to the 1 - 2 % level in the fumigated block you can reduce buffer zones by 20%,
increase soil organic content to 2 - 3 % and you get a 30% buffer zone reduction.
When devising a crop rotation strategy, a grower should also be aware of which crops and cover crops might
increase disease problems. Under wet conditions, sunn hemp can increase soil populations of Pythium and
Rhizoctonia damping-off fungi. Some varieties of cowpea may host of root-knot nematode. In organic systems,
cowpeas and other legumes may support populations of stink bugs which may cause problems in the fall. These
factors should all be considered before selecting a cover crop.
Soil solarization is the use of plastic tarps placed on the soil surface to increase soil temperatures to a level that
kills soilborne pathogens, weeds, and other crop pests. Soil solarization works best when summer temperatures
are uniformly high. These conditions don’t always occur in Florida. Soil solarization will not eradicate a
pathogen from a field, but it may lower pathogen populations.
Soil flooding is a related means of creating conditions—in this case, saturated soil over an extended period -
that might result in a decline of soil-borne pathogens.
A number of growers and researchers are looking with interest at anaerobic soil disinfestation (ASD), a non-
chemical alternative to fumigants, which can control soilborne pathogens and nematodes in strawberries and
vegetables. ASD works by creating anaerobic soil conditions by incorporating readily available carbon-sources
into topsoil that is covered with plastic tarp then irrigated to field capacity. The tarp is then left in place to
maintain soil moisture above field capacity and to sustain anaerobic conditions. Anaerobic decomposers are
then able to respire using the added carbon, which results in the build-up of anaerobic by-products that are toxic
to pathogens. These by-products are degraded rapidly once the tarp is removed or holes are made through the
tarp for planting.
In Florida, trials using composted broiler litter (to improve water holding capacity of sandy soils) and blackstrap
molasses incorporated as substrate, ASD treatments provided good control of nutsedge, and excellent control of
grass, broadleaf weeds, Phytophthora capsici, and Fusarium oxysporum f. sp. lycopersici.
The end of the season is also the ideal time to take samples taken to predict the risk of nematode injury to fall
crops 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. Plant roots should
also be examined visually for the telltale signs of galling caused by root knot nematode.
Recognizing that the root-knot 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 that 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.
The detection of any level of root galling usually suggests a nematode problem for subsequent plantings of
susceptible crops. Detection of a potential problem well in advance of the next growing season will provide
ample time to devise and implement an effective management strategy.
Integrated pest and disease management is a year-round commitment that should incorporate a combination of
cultural, biological and chemical pest management techniques.
FFVA Emerging Leader Development Program
Are you or someone who works for youan up-and-coming leader who wants to be more involved in the Florida
Fruit & Vegetable Association? Consider the FFVA Emerging Leader Development Program, administered by
the Florida Specialty Crop Foundation.
Applicants must be age 25 to 40, part of an FFVA member’s family or their company, and must be working in
or pursuing a career in Florida specialty crop agriculture. A class of eight to 10 members is selected each year.
Care to be a part of class 7? Applications are being accepted through business hours May 15, 2017. Download
the application here http://www.floridaspecialtycropfoundation.org/leadership/
Tomato Plant Destruction
Under Florida law, abandoned tomato fields that have not been destroyed within five days after final harvest are
subject to an Immediate Final Order (IFO) per Rule - FAC Chapter 5B-59.003, Tomato Plant Destruction.
You can report abandoned tomato fields by sending an email to the Division of Plant Industry describing the
physical location of the property. Their first route of destruction would be to make contact with the growers
and request compliance, if this does not occur an IFO is issued in which the grower has 10 days to correct the
problem.
Please contact Tyson Emery if you have any further questions.
Tyson Emery
Chief- Bureau of Plant and Apiary Inspection
Division of Plant Industry
Florida Department of Agriculture and Consumer Services
email: [email protected]
Phone: (352) 395-4709
See rule at https://www.flrules.org/gateway/RuleNo.asp?ID=5B-59.003
Opportunities to Get Core CEU’s Online
The CEU Series is published in Growing Produce on-line and is approved by FDACS and provides a
convenient way to earn CORE CEU's. Simply read an article and answer the questions at the end of the article.
A passing score of 75% or greater will earn you one CORE CEU.
There are currently several articles available and a new one will be published bi-monthly.
CEU Series: Learning About Pesticide Resistance is Anything but Futile
CEU Series: Improve Your Integrated Pest Management Program
CEU Series: Key in On the Contents of Pesticide Labels
CEU Series: Precaution Needed When Working with Pesticides
CEU Series: Get the Lowdown on Federal Pesticide Laws
CEU Series: Take into Account the Toxicity when Handling Pesticides
CEU Series: Be Aware of Bees When Applying Pesticides
CEU Series: Avoid Mishaps When Handling Pesticides
CEU Series: Make Sure to Stow Your Pesticides Before You Go
Here is a link to the latest article, CEU Series: Make Sure to Stow Your Pesticides Before You Go where you
will find links to all the previous articles. https://goo.gl/D27Ffr
EPA Manual Available on How to Comply with the Revised Worker Protection Standards
The EPA in conjunction with the Pesticide Educational Resources Collaborative (PERC) has made available a
guide to help users of agricultural pesticides comply with the requirements of the 2015 revised federal Worker
Protection Standard (WPS).
You should read this manual if you employ agricultural workers or handlers, are involved in the production of
agricultural plants as an owner/manager of an agricultural establishment or a commercial (for-hire) pesticide
handling establishment, or work as a crop advisor.
The “How to Comply” manual includes:
• details to help you determine if the WPS requirements apply to you;
• information on how to comply with the WPS requirements, including exceptions, restrictions, exemptions,
options, and examples;
• “Quick Reference Guide”- a list of the basic requirements (excluding exemptions, exceptions, etc.);
• new or revised definitions that may affect your WPS responsibilities; and explanations to help you better
understand the WPS requirements and how they may apply to you.
•
The revised EPA Pesticide Worker Protection Standard “How to Comply” Manual is available at:
https://www.epa.gov/pesticide-worker-safety/pesticide-worker-protection-standard-how-comply-manual
Meetings. Paper copies are available at the Hendry and Palm Beach County Extension Offices.
Up Coming Meetings
FSMA Produce Safety Alliance Classes - registration on-line through Event Brite
May 17 – Palmetto, FL - http://psa051717.eventbrite.com
June 4-6, 2017 Florida State Horticulture Society Annual Meeting
Westin Tampa Harbour Island
725 South Harbour Island Blvd
Tampa, FL 33602
For more information or to register, go to http://fshs.org/meetings/
June 8, 2017 33rd Annual Florida Seed Association Seed Seminar
UF/IFAS Southwest FL Research & Education Center
2685 SR 29
Immokalee, Florida 34142
9:00 a.m. – 3:00 p.m.
Advanced Registration $75, University Faculty & Staff $35, Students N/C (ID Required) includes lunch. A
great educational program is planned. All proceeds support the Florida Seed Association scholarship fund.
If you have any questions, please contact Arlen Wood at 863-660-6540 or email at [email protected]
Websites
Farm Dog - Florida Pest and Disease Pressure Map is now available! Discover agricultural pest and
disease trends near you in this interactive map. Updated daily. - free app at: http://scout-
dash.eastus.cloudapp.azure.com/regional
EDIS is the Electronic Data Information Source of UF/IFAS Extension, a repository of all IFAS Extension
publications - http://edis.ifas.ufl.edu/
Frequently Asked Questions on FSMA - Questions & Answers on the Food Safety Modernization Act -
http://www.fda.gov/Food/GuidanceRegulation/FSMA/ucm247559.htm
2016-2017 UF/IFAS Vegetable Production Handbook of Florida - This handbook is designed to provide
Florida growers with the latest information on crop cultivars, cultural practices, and pest management. Free
hard copies of the handbook are available at UF/IFAS research and education centers and county extension
offices. It can be viewed or downloaded at http://edis.ifas.ufl.edu/topic_vph
Check out Southwest Florida Vegetable Grower on Facebook https://www.facebook.com/pages/South-Florida-Vegetable-Grower/149291468443385 or follow me on
Twitter @SWFLVegMan - https://twitter.com/SWFLVegMan
All the best for a Happy Mother’s Day to all you Mothers
Contributors include: Joel Allingham/AgriCare, Inc, Javier Soto/West Coast Tomato Growers, Gordon
DeCou/Agri Tech Services of Bradenton, Dr Nick Dufault/ UF/IFAS, Carrie Harmon/UF/IFAS Plant Disease
Clinic, Sarah Hornsby/AgCropCon, , Bruce Johnson/General Crop Management, Barry Kostyk/SWFREC, Leon
Lucas/Glades Crop Care, Chris Miller/Palm Beach County Extension, Gene McAvoy/Hendry County
Extension, Alice McGhee/Thomas Produce, Dr.Gregg Nuessly/EREC Chuck Obern/C&B Farm, Dr. Monica
Ozores-Hampton/SWFREC, Dr. Rick Raid/ EREC, Ryan Richards/The Andersons, Dr Pam Roberts/SWFREC,
Dr. Nancy Roe/Farming Systems Research, Wes Roan/6 L's, Dr. Dak Seal/ TREC, Kevin Seitzinger/Gargiulo,
Crystal Snodgrass/Manatee County Extension, Dr. Phil Stansly/SWFREC, Dr. Josh Temple, DuPont Crop
Protection, Dr Gary Vallad/GCREC , Mark Verbeck/GulfCoast Ag, Dr. Qingren Wang/Miami-Dade County
Extension, Alicia Whidden/Hillsborough County Extension, Dr Henry Yonce/KAC Ag Research and Dr.
Shouan Zhang/TREC.
The South 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 Gene McAvoy
County Extension Director / Extension Agent IV
Regional Specialized Agent - Vegetables/Ornamental Horticulture
Hendry County Extension Office 863-674-4092 phone
PO Box 68 863-673-5939 mobile
LaBelle, Florida 33975 863-674-4637 fax
Web: http://hendry.ifas.ufl.edu/ [email protected]
Chris Miller Christian Miller
Extension Agent II – Vegetable Production & Tropical Fruits
Palm Beach County Extension
559 North Military Trail, West Palm Beach, FL 33415
Special Thanks to the generous support of our sponsors; who make this publication possible.
Thomas Produce Company Of South Florida
Grower and Shippers of Quality Vegetables
9905 Clint Moore Road
Boca Raton, Florida 33496
Carol Howard
Mobley Plant World 1351 W Cowboy Way
LaBelle, Florida 33935
Phone 863-675 -2020
Nichino America Makers of Courier, Portal & Vetica
Technical Sales Representatives
Todd Villars: West Florida - 863-532-0937
Sam Monroe: East Florida - 772-473-0873
Gargiulo Growers Shippers Importers Exporters
David Pensabene: Production Manager
Naples Operations
Phone 239-353-0300 Fax 239-353-3407
Ed Early
DuPont Crop Protection Fort Myers, Florida 33911
Mobile 239-994-8594
Dr. Nancy Roe
Farming Systems Research 5609 Lakeview Mews Drive
Boynton Beach, Florida 33437
Phone 561-638-2755
Ryan Richards
The Andersons 710 Broward Street
Immokalee, FL 34142
Phone 239-657-8254 Fax 239-657-2005
Shawn Barley
Wedgworth’s Inc. Big W Brand Fertilizer
(863) 441-9255 cell
Phone: 561-233-1718
Email: [email protected]
Web:
http://discover.pbcgov.org/coextension/Pages/defa
ult.aspx
Special Thanks to the generous support of our sponsors; who make this publication possible.
Bart Hoopingarner
Gowan Company 3605 162nd Ave East
Parrish, FL 34219
Phone 941-776-1105 Cell 941-737-7444
Justin Powell
Southeast Business Leader
Adama 229 881 9757 cell
OmniLytics - AgriPhage Safe Natural Effective
Vegetable Bacteria Control
Dave Cole - 561-261-1545
Tony Swensen - 801-808-2132
Sponsored by Orondis® fungicide &
Syngenta Crop Protection Cody Hoffman
Fort Myers, FL 33901
Cell 321- 436-2591
Certis USA Bio-Pesticides for Crop Production
Joe Craig - 863-291-9203
Chuck Goodowns - 352-538-4471
Dave Owens
Marrone Bio Innovations Cell 239-233-9073 or
Brent Beer
Beer Leveling &
Land Development Office 863-675-1663 863-673-3173 cell
158*17*43857 Nextel
Scott Houk
Dow AgroSciences LLC
Phone 239-948-3999
Email [email protected]
Glades Crop Care, Inc. Leaders in Crop Health
Management
Charlie Mellinger, Ph.D.
Phone 561-746-3740 Fax 561-746-3775
Stacey Howell
Bayer CropScience 3481 3rd Ave NW
Naples, FL 34120
Phone (239) 353-6491 Cell (239) 272-8575
Steve Mike Dave
Jamerson Farms
Growers, Packers and Shippers of
Florida’s Finest Vegetables
Phone 239-229-5734 Fax 239-368-0969
FMC
FMC Corporation APG Ron Palumbo
Cell 305-304- 7941
Ronald [email protected] www.fmccrop.com
Special Thanks to the generous support of our sponsors; who make this publication possible.
Sarah Hornsby, CCA
Agricultural Crop Consulting, Inc Scouting: Manatee, Hillsborough, Collier
Office/Fax 941-776-1122
Cell 941-713-6116
Email: [email protected]
Garry Gibson
BASF Corporation 1502 53rd Avenue
Vero Beach, Florida 32966
Office 772-778-4646 AGNET 21726
Certified for use in Organic Production
Jack Kilgore 239-707-7677
Donald Allen
AGLIME SALES INC PO Box 60
Babson Park, Florida 33827-0060
Office 863-638-1481 Fax 863-638-2312
Mobil 863-287-2925
Chuck Obern
C & B Farm CR 835
Clewiston, FL 33440
Office 863-983-8269 Fax 863-983-8030
Cell 239-250-0551
Scott Allison
Diamond R Fertilizer PO Box 1898
LaBelle, FL 33975
(863) 675-3700
Arysta Life Science
Richard Royal 352 434-8774
Shaun Yule 386 561 0493
PUT YOUR NAME HERE
Valent USA
"Products That Work
From People Who Care"
Sarah Markle 863-673-8699
Richard Roles
Roles Marketing International Distributors of Agrigro and Super
Cal 10% Calcium
[email protected] www.rmiint.com
Cell 561-644-3511
BioSafe Systems LLC
OxiDate®
TerraClean®
StorOx®
Jarod Huck
352-789-9363
Luis Hansen
305.793.9206
Special Thanks to the generous support of our sponsors; who make this publication possible.
NOTE: The acknowledgement of sponsorship in no way constitutes or reflects an official endorsement of these
businesses or their products or services by either the University of Florida, IFAS, the Florida Cooperative Extension
Service, or the Hendry County Extension Office. Sponsors have no control over the content of this publication.
PUT YOUR NAME HERE
Dr. Henry Yonce
KAC Agricultural Research Scouting, Consulting
Research
386-736-0098 work 386-527-1124 cell
PUT YOUR NAME HERE
Grower's Management, Inc P.O. Box 130
Belle Glade, FL 33430
Phone: 561-996-6469
www.growersmanagement.com