|
SOUTH
FLORIDA
VEGETABLE
PEST AND DISEASE
HOTLINE |
March 9, 2017
Heavy winds
buffeted the area for several days once again this week battering crops and
damaging plants and fruit especially in younger plantings in the Manatee Ruskin
area.
Temperatures have
been relatively mild with daytime highs in the upper 70’s and low 80’s and
night time temps in the 50’s and 60’s.
Most areas
received between a half inch and an inch and a half of rain for the period with
the exception Okeechobee which reported just over a quarter inch. Heavy dews and morning fog over the past few
weeks have helped keep some diseases active.
FAWN Weather
Summary
|
Date
|
Air Temp °F
|
Rainfall
|
Ave Relative Humidity
|
ET (Inches/Day)
|
|
|
|
Min
|
Max
|
(Inches)
|
(Percent)
|
(Average)
|
|
Balm
|
|
|
|
|
|
|
2/12 – 3/3/17
|
36.65
|
86.92
|
1.03
|
77
|
0.1
|
|
Belle Glade
|
|
|
|
|
|
|
2/12 – 3/3/17
|
44.46
|
88.66
|
0.77
|
84
|
0.11
|
|
Clewiston
|
|
|
|
|
|
|
2/12 – 3/3/17
|
44.65
|
86.88
|
0.77
|
81
|
0.11
|
|
Ft Lauderdale
|
|
|
|
|
|
|
2/12 – 3/3/17
|
56.12
|
89.55
|
1.42
|
78
|
0.11
|
|
Homestead
|
|
|
|
|
|
|
2/12 – 3/3/17
|
47.55
|
87.04
|
1.12
|
82
|
0.11
|
|
Immokalee
|
|
|
|
|
|
|
2/12 – 3/3/17
|
41.19
|
86.88
|
1.39
|
83
|
0.11
|
|
Okeechobee
|
|
|
|
|
|
|
2/12 – 3/3/17
|
34.51
|
89.80
|
0.33
|
81
|
0.1
|
When in Doubt – Scout!
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Pest and
disease pressure has been relatively light this season. Heavy winds at the end of January which
battered and sand blasted crops, caused extensive scarring of fruit which is
being reflected in relatively high cull rates at the packinghouse. Unseasonably
warm conditions have caused lettuce and other crops to bolt prematurely and is
pushing early maturity in a variety of crops.
A variety of crops are coming to market including collards, cucumber,
eggplant, escarole, green beans, herbs, kale, lettuce, mustard, peppers,
radishes, squash, sweet corn, Swiss chard and a variety of specialty items.
The National
Weather Service forecast advises that over the weekend, a front, currently
taking shape over the northern Plains states, will make a run at the area
Saturday, but appears likely to wash out as it approaches the area with no major
change in air mass expected. Isolated to
scattered showers along this decaying boundary are possible over the weekend.
Next week, a
stronger front to approach the area Monday or Tuesday, bringing an increased
chance for scattered showers. The air mass behind this front does not look
particularly cool and it is more likely to usher drier air into the region by
the middle of next week.
For additional
information, visit the National Weather Service in Miami website at http://www.srh.noaa.gov/mfl/newpage/index.html
Insects
Whiteflies
Around
Southwest Florida, growers and scouts report that whiteflies remain the pest of
the day and counts remain high in many locations but respondents indicate
numbers seem to be declining in a number of locations.
Reports
indicate that TYLCV is moving in places especially where growers are not using
TYLCV resistant cultivars, and there is a fair amount of cucurbit leaf crumple
virus showing up in watermelons already.
Scouts
are also finding some cucurbit yellow stunting disorder virus as well as vine
decline (squash vein yellowing virus) in watermelon.
Respondents in
Miami Dade County indicate that whitefly remains common on tomato, eggplant, squash
and other host crops. TYLCV is common
in many tomato fields and has reached nearly 100% infection levels in a few.
Cucurbit crops
at various locations around Miami-Dade are also showing high incidence of
silverleaf stemming from heavy whitefly infestation.
In the Manatee
Ruskin area, whitefly numbers remain fairly low in spring plantings but growers
report a significant amount of TYLCV is present in several fields and could
indicate problems as the season progresses.
In the Palm
Beach area, whiteflies remain an issue in some squash and eggplant, but growers
are managing to keep them under control in other crops. Whiteflies are reportedly building up in
leafy brassicas in the Glades.
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, I have visited literally have
clouds of whiteflies streaming out of them and settling on nearby spring
plantings. This situation does not bode 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
|
|
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**
|
|
|
|
|
|
Unk.
|
horticultural mineral oil
|
F†
|
|
G
|
|
|
|
Unk.
|
Azadiractin
|
F†
|
|
|
|
|
|
Unk.
|
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
Aphids
Around Palm Beach County, respondents
report a spike in aphid populations with quite a few now blowing around, in
some cases out of old crops, and trying to build up in nearby pepper and
eggplant fields.
Growers and scouts in Southwest Florida,
report that aphids are still fairly low overall but have flared up in some
locations.
In the EAA, aphids are present on corn
approaching maturity but have not become a problem on flags and silks. Aphids are also showing up in brassicas.
Pepper Weevil
Pepper weevils are established in a number
of pepper fields around Southwest Florida and numbers are building in a number
of places as the season progresses
Reports from East Coast production areas
indicate that pepper weevil numbers are high in many areas and will impact
extended production in older pepper. Scouts
report signs of finding foliar feeding in eggplant in some places. Young pepper
planted near older fields are at the highest risk.
Pepper weevils are becoming common in the
Homestead area.
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.
Worms
Around Southwest Florida, worm pressure is
starting to pick up with a mixed bag of southern, beet and fall armyworms plus
loopers, melonworms, and fruit worms depending on the location. A
few diamondback moths are showing up in crucifers.
On the East Coast, worms are not doing much
and worm pressure remains mostly low. Respondents
indicate that diamondback moths are causing some problems in leafy brassicas.
Reports from the Ruskin area indicate that
worm pressure has been steadily increasing over the past few weeks. Respondents report a surge in diamondback
moth activity in crucifers. Around
Wimauma, pinworms have reached high numbers in some tomato fields and are
causing problems.
Around Homestead, worms are active in a
variety of crops.
Respondents in the Glades indicate that worms
continue at above average numbers but have been manageable in most cases. The areas closest to the lake have seen
the highest sustained pressure until tasseling when silk sprays control
them.
Lesser cornstalk borer
Around the Glades, lesser cornstalk borer
trap counts remain extremely high on the sand lands around Clewiston due to the
dry weather. Depending on location
numbers are up and down based on moisture levels in the field. Counts on muck soils remain steady at much
lower populations.
Thrips
On the East Coast, respondents indicate thrips
are increasing and affecting pepper quality in most areas in Palm Beach County.
They are reportedly less of a problem in
Martin and St Lucie counties.
Around Homestead, common blossom thrips and
western flower thrips, vector of TCSV and other tospoviruses continue to be a
threat. Growers should scout fields
carefully to detect their presence in tomato as well as weedy hosts near the
fields and in the surrounding area.
Tomato chlorotic spot virus is widely present in a number of tomato
fields. Reflective plastic mulch may be
useful to repel thrips early in the cropping cycle.
Melon thrips are also causing 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.
Thrips have been mostly low in South
Florida but scouts continue to report finding a few thrips vectored groundnut
ringspot virus and tomato chlorotic spot virus infected plants here and there.
Around Southwest Florida, thrips palmi are still
around, causing some problems in pepper and watermelon.
Around Hillsborough County, thrips numbers
remain low but appear to be increasing as the migrate out of flowering oak
trees.
Growers 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.
Leafminer
Growers in the Manatee Ruskin are report
that leafminer numbers are increasing in spring plantings.
Reports from East Coast growing areas in
Palm Beach and Martin Counties indicate that leafminer continues to cause
problems in a number of places.
Around Immokalee, leafminers remain a persistent
problem on tomato, eggplant, pepper and cucurbits. Numbers are up and down depending on
location.
Respondents indicate that leafminers
continue to cause problems in many EAA crops.
In Miami-Dade County, leafminers are quite
common on many vegetable crops including tomato, pepper, basil, even cabbage.
Leafminers are particularly damaging on
celery, crucifers, cucurbits, okra, potato and tomato. In south Florida, populations peak between
October and March while in central Florida they are a problem in both spring
and fall.
Certain insecticides may decimate
beneficial insects including those that attack leafminer. This often results in a larger leafminer
problem if the pesticide reduces numbers of leafminer parasites.
Several parasites for this insect have been
recorded in Florida, but parasitic wasps are most common. Up to 90% parasitism in non-sprayed tomatoes
has been observed in Florida.
To determine whether leafminer larvae are
dead or alive, leaflets can be held up to the sun and examined with a hand
lens. Living larvae are a pale yellow and flush with the end of the mine.
The back and forth feeding movements are readily visible, although movement may
cease when larvae are disturbed or molting. Dead larvae do not show movement
and are usually discolored and removed from the ends of mines.
It is important that the scouting program
include not only an assessment of the number of leafminers present but also the
natural enemies.
Growers can use Entrust, Radiant, Coragen,
Verimark, Exirel, Durivo, Agrimek, Tigard, and Neemix for leafminers depending
on the crop and label.
Spider mites
Spidermites are increasing in a number of
locations and some of melons and tomatoes around SW Florida have been
sprayed.
Spidermites are also starting to show up in
a number of locations around South Florida on cucurbits, eggplant and
tomatoes.
Broad Mites
Around South Florida, broad mites remain
widely present at mostly low levels in pepper and eggplant.
Silkfly
In the EAA, silk flies are present in
typical numbers for this time of year with the pressure varying by
location. In general, the closer to the
lake, the higher the pressure.
Around Homestead, corn silk fly number are
increasing and will most likely grow worse with the progression of season.
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.
Stinkbugs
Growers and scouts are finding stinkbugs
and leaffooted bugs especially in older plantings and some growers have had to
apply pyrethroids. Several scouts
have noted an increase in stinkbugs especially where more selective insecticide
are being applied.
Yellowmargined Leaf Beetle
A few yellowmargined leaf beetle have been
reported in leafy brassicas in the EAA and Hendry County.
The adult beetle is about 5 mm long and
predominately dark brown, bronze or black. The margins of the elytra or
hardened forewings characteristic of beetles are marked with a margin of yellow
or brown, a characteristic which gave this species its common name.
The eggs are bright orange, elongate, and
laid singly or in small groups on plant stems, under fallen leaves or on the
soil surface.
The normal hosts for this species are all
in the plant family Cruciferae. Vegetable crops that are damaged include broccoli,
cabbage, cauliflower, collards, mustard, radish, turnip, and watercress. The yellowmargined
leaf beetle is a particular problem on Chinese cabbage and other leafy
Brassicas in the Glades, especially for organic growers.
Most damage occurs in the spring when both
the larvae and adults are found feeding on crucifers, where they feed on the
foliage and leaf margins, making small holes. Adults and larvae may
defoliate the host. Larvae, especially early instars, work in groups to strip
individual stems.
Diseases
Late Blight
Late blight appears to be slowing down in
most places around Southwest Florida but and is now present a number of farms
in Collier and Hendry Counties and has reached pretty serious levels in some
locations.
There has been one report of late blight
from Manatee County.
The gusty winds and rain at the end of the
month helped to move it around and foggy mornings over the past few weeks have
helped keep it going.
Since this disease can spread so rapidly,
growers should scout their fields thoroughly each day, especially when cool and
wet conditions conducive to disease development prevails.
Late blight symptoms on leaves appear as
irregularly shaped brown to purplish lesions with indefinite border lesions
that can span veins. The lesions may be seen any time of day, on any stage
of plant growth and on leaves of any age.
Velvety, white fungal growth may appear on the lower surface of affected
leaflets early in the morning before leaves dry and/or in the lower canopy.
On stems, purplish lesions may be found
anywhere on the stem. Cottony, white
growth of fungus on stems with lesions can often be seen early in the morning
and/or in the lower canopy. Stems with
lesions are brittle and break easily. Lesions are confined to epidermis and
cortex. Leaf rolling and wilting is
often associated with stem lesions and purpling of leaflets may occur in some
varieties.
Begin a spray program with fungicides if
late blight is in your area or weather conditions are suitable for late blight
development. After potato harvest, kill infected foliage to minimize tuber
infection.
Currently, fungicides are the most
effective means of controlling late blight and will remain the primary tool
until cultivars with resistance to this disease become available.
Fungicides slow the rate at which the disease develops in the field by creating
a protective barrier on the foliage.
Just applying a chemical, however, does not
necessarily equate with effective disease control. Relative effectiveness
of a product, coverage, and timing must be factored into the equation for
maximum benefit.
Numerous fungicide products are registered
for late blight control.
Protectants, as the name implies, protect foliage from infection by spores. Protectant chemicals must be well distributed
over the leaf surface and must be applied before spores land on leaves. They are ineffective against established
infections.
PROTECTIVE applications of chlorothalonil
are your first line of defense for managing late blight. Timing is critical
- applications must be made when conditions are conducive for disease
development and before infection occurs!!!
They may kill some established infections
and may suppress production of new spores. Even a short break in spray schedules, despite
what is said regarding some of the newer fungicides, can result in a dramatic
increase in blight under the proper conditions.
Consult current UF/IFAS recommendations for
all labeled fungicides for the control of late blight on tomato in
Florida.
Go to for the most recent update: http://edis.ifas.ufl.edu/pdffiles/cv/cv13700.pdf.
Due to low prevailing prices, many tomato
fields have been picked once or twice and abandoned, even though most have been
sprayed with a burn down herbicide, coverage in many fields has been so-so and
I am seeing a lot of green amongst the dead foliage which could provide an
ideal breeding ground and source of inoculum for nearby by fields. In a few locations abandoned fields have
resulted in serious problems for neighboring plantings. Abandoned fields should be sprayed and then
disked under.
In addition, low prices have caused some
growers to be hesitant to spend money on crop protectant materials and
unfortunately the more efficacious materials tend to be pricey. Should markets rebound this may prove to be a
false economy as it could negatively impact successive plantings.
In Florida, it has been observed that
seldom does a widespread late blight epidemic occur on tomatoes in the Manatee-Ruskin
area unless the disease was present in the Immokalee area and/or Dade County. Since late blight has been confirmed on
tomato in Immokalee growers in other areas are advised to adhere to a
preventative spray program.
See USABlight for more info and photos -
http://usablight.org/lateblight
Target Spot
Around Immokalee, target spot remains
mostly low in tomato.
Respondents on the East Coast target spot
is becoming common in older tomato. Incidence ranges from low to fairly high
depending on the location.
Growers and scouts should be alert for the
presence of target spot as canopies begin to close in tomato plantings.
Foliar symptoms of target spot caused by
Corynespora cassiicola consist of brown black lesions with subtle concentric
rings giving them a target-like appearance.
Lesions can be confused with early blight. Foliar symptoms of early
blight caused by Alternaria solani also consist of brown black lesions with
conspicuous concentric rings and but are often associated with a general chlorosis
(yellowing) of the leaf.
Target spot has become one of the hardest
to control pathogens in tomato. Good
rotations and tank mixes are the best option.
Newer fungicides such as Endura, Scala,
Inspire Super, Reason, Luna, Tanos and Fontelis have provided growers with new
tools to manage this disease.
Consult UF/IFAS recommendations for currently labeled fungicides for
target spot control in Florida tomatoes.
http://edis.ifas.ufl.edu/pdffiles/cv/cv13700.pdf
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:
tyson.emery@freshfromflorida.com
Phone:
(352) 395-4709
See
rule at https://www.flrules.org/gateway/RuleNo.asp?ID=5B-59.003
Bacterial Spot
Around Southwest Florida, bacterial spot is
present at low levels but is still creeping around is some pepper and tomato fields.
On the East Coast, bacterial spot is increasing
in non- resistant pepper and in tomato.
Bacterial leaf spot is remains active in a
number in tomato fields around Homestead.
Bacterial Speck
Low levels of bacterial speck have been
reported around SW Florida following recent rains.
Early Blight
Alternaria is increasing on tomato around south
Florida. Some of this is associated
with leafminer damage.
Target Spot
Reports indicate that target spot is also
increasing on tomato in a number of places around South Florida. The Manatee Ruskin area remains clean as
most plants are still young.
Powdery Mildew
Growers and scouts report that powdery
mildew is active and increasing in cucurbits around SW Florida, mostly squash
but also a few watermelons.
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 continues to
cause some problems in cucurbits.
Downy mildew is also present on squash in
Homestead.
In the EAA and elsewhere, downy mildew is causing
some issues in cole crops including cabbage, kale and radish.
In the Glades, downy mildew on lettuce remains
persistent, generally at low levels due to good management.
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 including some patching and aerial infection. It is also hitting some eggplant where fruit
are becoming infected on the ground as well as some double crop squash.
Stemphylium leaf spot
Respondents in the Glades continue to
report some issues with Stemphylium leaf spot on spinach.
Initial symptoms of Stemphylium leaf spot
on leaves consist of small (0.13 to 0.25-inch diameter), circular to oval, gray‑green leaf spots. As the disease
progresses, leaf spots enlarge, remain circular to oval in shape, and turn tan
in color.
Older spots coalesce, dry up, and become
papery in texture. Visual signs of fungal growth are generally absent from
the spots; hence this problem is readily differentiated from foliar diseases in
which purple growth (downy mildew), green spores (Cladosporium leaf spot), or
acervuli (anthracnose) develop within circular lesions.
Overall, symptoms resemble the tan,
circular spots caused by pesticide or fertilizer damage.
Weeds or other reservoir hosts have not
been identified. This pathogen is seed-borne. Hot water or chlorine treatment of seed may
help reduce chances of seed-borne transmission.
Dr Richard Raid Pathologist at UF/IFAS EREC
reports that strobilurin fungicides have been effective in the past trials but
is conducting additional trials to look at other compounds.
Dr Raid invites growers who wish to discuss
control options to contact him at rnraid@ufl.edu.
Tomato Chlorotic Spot Virus
Around Southwest Florida, scouts have found
a few scattered single TCSV infected plants here and there in a few tomato
fields.
Growers and scouts report an “outbreak” of
TCSV on tomato and pepper in a fairly localized area in Palm Beach County. Incidence in pepper has reached 30% in some
fields.
In the Homestead area, respondents indicate
that almost all tomato fields have low levels of TCSV.
The virus is spread by thrips. TCSV is known to be transmitted by three
species of thrips: common blossom thrips (Frankliniella schultzei), western
flower thrips (F. occidentalis), and flower thrips (F. intonsa) (Wijkamp et al.
1995). The first two are the likely
culprits in Florida.
Interestingly, TCSV and TSWV are not
transmitted at similar efficiencies by the same thrips. In studies, the
most efficient TCSV vectors appears to be the dark form of F. schultzei followed by F.
occidentalis.
There
has been talk by growers in the affected area of Palm Beach County of seeing
“black” thrips in their fields, possibly F.
schultzei.
Growers should scout fields and target
thrips more aggressively if they are seeing viral plants becoming common in
their fields.
In young fields, where growers are seeing a
few scattered infected plants, growers would be advised to remove infected
plants to limit secondary spread.
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.
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.
TYLCV remains low in East Coast.
TYLCV is common around Homestead and
infection rates are approaching 100% in some isolated fields.
TYLCV is increasing around SW Florida and
has reached 3% incidence in some older fields and isolated plants are showing
up in new plantings in some younger fields.
With the huge number of whitefly moving off
abandoned fields, lack of cold weather and very high whitefly counts being
reported in a number of new planting, 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.
Rouging infected plants in younger fields
is advised.
Watermelon mosaic virus
Growers in few locations around Southwest
Florida are experiencing problems with mosaic in melons and squash.
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 at low levels in watermelons.
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.
In short, the stage is being for these
whitefly vectored viruses to be an issue in spring watermelon production (and
other cucurbits) in South Florida.
While there is no way to know if the will
be a problem, growers are advised to scout fields for whiteflies and
virus.
Management practices:
Be alert for and eliminate cucurbit weeds
around melon fields.
Use a soil-applied neonicotinoid
insecticide such as imidacloprid (Admire®), thiamethoxam (Platinum®), or
dinotefuran (Venom®) should be used at planting for longer season cucurbits,
such as watermelon and calabaza, and possibly for green beans (imidacloprid
only).
If a foliar application of a neonicotinoid
insecticide such as acetamiprid (Assail®), dinotefuran, or thiamethoxam
(Actara®), is used instead of a soil application, it is best to apply it in the
first 30 days of the crop, before flowering (pollinator protection).
Switch to non-neonicotinoid insecticide
classes after flowering, and do not use any neonicotinoid class insecticides
for the remaining cropping period.
Spiromesifen (Oberon®) is effective against
immature stages of the whitefly.
IGRs - (buprofezin (Courier ®),
pyriproxyfen (Knack®) to control nymphs may be effective.
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 both northern corn leaf blight and southern 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.
Southern corn leaf blight is caused by the
fungus Bipolaris maydis. Symptoms of Southern corn leaf blight
typically occur on leaves. Mature foliar
lesions can be rounded on the sides but they tend to be parallel-sided, often
restricted by the veins.
Lesions are light tan in the center with a
reddish-brown border. A greenish
growth near the center of the lesion may be evident if spores are present.
Mature lesions range from 1/4 to 1 1/2 inches in length and may be tapered,
flat or serrated on the ends.
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.
Southern rust
Respondents also report finding low levels
of southern rust in sweet corn as well.
Growers should begin spraying at the first
sign of rust.
Bean Rust
Reports from the Glades indicate that low
levels of rust are starting to show up in some beans.
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.
News You Can
Use
EPA Finalizes Steps to Better Protect Bees
from Pesticides
EPA’s
is releasing a final policy which describes methods for addressing acute risks
to bees from pesticides. Applications of acutely toxic pesticides would be
prohibited under certain conditions when bees are most likely to be present.
While the restrictions focus on managed bees, EPA believes that these measures will
also protect native bees and other pollinators that are in and around treatment
areas. New label language will protect managed bees under contract to provide
crop pollination services.
The
final Policy to Mitigate the Acute Risk to Bees from Pesticide Products is more
flexible and practical than the proposed policy. For example, a product that
retains its toxicity to bees for a shorter time might be allowed to be applied
under certain circumstances. Also, in some cases, pesticide application would
be allowed when it is unlikely that pollinators will be foraging for crops that
have extended bloom periods. The EPA will begin implementing this policy in
2017 by sending letters to registrants describing steps that must be taken to
incorporate the new labeling.
EPA
continues to encourage efforts by states and tribes to reduce pesticide
exposure to bees and other insect pollinators through locally-based measures,
such as through Managed Pollinator Protection Plans (MP3s). EPA will continue
to assist the American Association of Pest Control Officials in developing
performance measures for MP3s and will continue to monitor the progress and
effectiveness of pollinator protection plans in reducing bee exposure to
pesticides. EPA has also engaged the Pesticide Program Dialogue Committee in
examining the best ways to measure the effectiveness of MP3s.
For
more information on the proposal, its supporting documents, and comments
received, please see regulatory docket EPA-HQ-OPP-2014-0818.
EPA’s
Actions to Protect Pollinators
Pollinator
Protection at EPA
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:
tyson.emery@freshfromflorida.com
Phone:
(352) 395-4709
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
Here
is a link to the latest article, CEU Series: Be Aware of Bees When Applying
Pesticides where you will find links to all the previous articles. http://tinyurl.com/j7bshef
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
March 24, 2017 Spanish Worker Protection Standard Train the Trainer 9am – 3pm
UF/IFAS Hendry
County Extension Office
1085 Pratt
Boulevard
LaBelle, Florida
Cost
is $20
RSVP
to m.watkins@ufl.edu or call (863) 674-4092.
March 29, 2017 UF/IFAS Southwest Florida Research and Education Center Open
House
SWFREC
will be having an Open House on Thursday, April 6, 2017 from 10 am to 3 pm.
Open
to the public – come learn about research and extension activities that touch
every community in southwest Florida
RSVP
by phone at 239-658-3400 or email jderleth@ufl.edu
April 6, 2017 UF/IFAS Everglades Research and Education Center Open House
The
Everglades Research and Education Center will be having an Open House on
Thursday, April 6, 2017
Registration
begins at 8 a.m.
Included
will be:
· Field Tours
· Lab Tours
· Presentations
· Poster exhibit
The
day will conclude with a complimentary lunch.
The
theme for the day is “The Value of Science”
Please
wear sensible clothes and shoes for touring Farm Trials
Please
register online by Monday, April 3
April 6, 2017 Spanish Pesticide Applicator Training - CORE 9 am
April 7, 2017 Spanish Pesticide Applicator Training - Private 9 am
Hendry County
Extension Office
1085 Pratt
Boulevard
LaBelle, Florida
Cost
is $10 per class.
RSVP
to m.watkins@ufl.edu or call (863) 674-4092.
FSMA Produce Safety Alliance Classes - registration
on-line through Event Brite
March
13 – Arcadia, FL - http://psa031317.eventbrite.com
March
16 – Homestead, FL - http://psa031617.eventbrite.com
March
20 – St. Augustine, FL - http://psa032017.eventbrite.com
April
20 – Tavares, FL - http://psa042017.eventbrite.com
May
17 – Palmetto, FL - http://psa051717.eventbrite.com
April 24-26, 2017 FSMA Preventive Controls for Human Food Rule
classes
For
more information and to register, use the links below:
Lake
Alfred, February 8-10
https://www.eventbrite.com/e/fspca-training-lake-alfred-registration-28581155004
Gainesville,
April 24-26
https://www.eventbrite.com/e/fspca-training-gainesville-registration-29441832313
Websites
Seeing
Theory - Statistics, is quickly becoming the most important and
multi-disciplinary field of mathematics. Statistical literacy is essential to our data driven society. A common
source of misunderstanding of scientific data is confusion about statistics and
probability. This site has some very cool visualizations to explain the
basics of probability and statistics. http://students.brown.edu/seeing-theory/
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
Quotable Quotes
A
smile is happiness you'll find right under your nose. - Tom Wilson
Two
things define you: Your patience when you have nothing and your attitude when
you have everything. – Anon
"If
you light a lamp for someone else, it will also brighten your path."
Empty
pockets never held anyone back. Only empty heads and empty hearts can do that.
– Norman Vincent Peale
Do
the best you can until you know better. Then when you know better, do better. –
Maya Angelou
Time
is more valuable than money. You can get more money, but you cannot get more
time. – Jim Rohn
On the Lighter Side
Private Lecture
Ron
Chester, 89 years of age, was stopped by the police around 2 a.m. and was asked
where he was going at that time of night.
Ron
replied, "I'm on my way to a lecture about alcohol abuse and the effects
it has on the human body, as well as smoking and staying out late."
The
officer asked, "Really? Who's giving that lecture at this time of
night?"
Ron
replied, "That would be my wife."
Pups for Sale
A
farmer had some puppies he needed to sell. He painted a sign advertising the 4
pups and set about nailing it to a post on the edge of his yard. As he was
driving the last nail into the post, he felt a tug on his overalls. He looked
down into the eyes of a little boy.
"Mister," he said, "I want to
buy one of your puppies."
"Well,"
said the farmer, as he rubbed the sweat off the back of his neck, "These
puppies come from fine parents and cost a good deal of money."
The
boy dropped his head for a moment. Then reaching deep into his pocket, he
pulled out a handful of change and held it up to the farmer.
"I've
got thirty-nine cents. Is that enough to take a look?"
"Sure,"
said the farmer. And with that he let out a whistle. "Here, Dolly!"
he called.
Out
from the doghouse and down the ramp ran Dolly followed by four little balls of
fur. The little boy pressed his face against the chain link fence. His eyes
danced with delight. As the dogs made their way to the fence, the little boy
noticed something else stirring inside the doghouse.
Slowly
another little ball appeared, this one noticeably smaller. Down the ramp it
slid. Then in a somewhat awkward manner, the little pup began hobbling toward
the others, doing its best to catch up...
"I
want that one," the little boy said, pointing to the runt.
The
farmer knelt down at the boy's side and said, "Son, you don't want that
puppy. He will never be able to run and play with you like these other dogs
would."
With
that the little boy stepped back from the fence, reached down, and began
rolling up one leg of his trousers. In doing so he revealed a steel brace running
down both sides of his leg attaching itself to a specially made shoe. Looking
back up at the farmer, he said, "You see sir, I don't run too well myself,
and he will need someone who understands."
With
tears in his eyes, the farmer reached down and picked up the little pup.
Holding it carefully he handed it to the little boy.
"How
much?" asked the little boy...
"No
charge," answered the farmer, "There's no charge for love."
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
