New Insecticide Chemistries for Management of Silverleaf Whitefly
Transcript of New Insecticide Chemistries for Management of Silverleaf Whitefly
New Insecticide Chemistries for Management of
Silverleaf WhiteflyAlton N. Sparks, Jr.
Extension EntomologistUniversity of Georgia, Tifton Campus
New Insecticides for Whiteflies
• Movento (spirotetramat)• Coragen (chlorantraniliprole) • First impressions and current view• Understanding of a products
capabilities is necessary for incorporation into IPM programs and evaluation.
Silverleaf Whitefly
• Bemisia tabaci, (B. argentifolii) • Silverleaf/Sweet potato/Poinsettia • Wide host range• Likes hot dry weather• Primarily summer/fall pest in Ga.• Damage:
– Feeding, honeydew, sooty mold– Plant disorders, virus vector
Whitefly Management• Do not overwinter populations• Start fields clean (clean transplants)• Separate hosts crops when possible• Avoid susceptible crops in fall if
possible• Insecticides
– Soil applied systemic– Foliar insecticides
Systemic Insecticides for SLWF
• Neonicotinoid insecticides–Admire Pro (generics)–Platinum–Venom
• Coragen• Durivo (Coragen+Platinum)
Foliar Insecticides for SLWF• Pyrethroids + organophosphates• Endosulfan• Neonicotinoids (Actara, Assail, Venom)
• Knack• Courier• Rimon• Oberon, Movento• Coragen (Voliam)
Movento• A.I. – spirotetramat (Group 23)• Bayer CropScience• Movento
–Highly systemic–Foliar applications only–Adjuvant necessary (on label)–Aphids, whiteflies
PhloemUpward and downwardtransport
XylemUpwardtransport
Spirotetramat application sites
Artificial caged infestation of Green Peach Aphid was controlled 3 days after application
Behavior within the Plant
Mealy Plum Aphid Fresno, CA – 2006 on French
Prune
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7 14 21 29 36 42
Untreated
PROVADO - 6 fl oz
MOVENTO - 5 fl oz
MOVENTO - 5 fl oz +0.25% Succeed
MOVENTO - 5 fl oz +0.834% Induce
MOVENTO - 5 fl oz +0.21% Silwet
ID06NARSKHURW1. Dr. Richard Warner – Bayer CropScience.
% In
fest
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erm
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DATWith surfactants
Surfactant Impact:
Coragen• A.I. – chlorantraniliprole (rynaxypyr)• DuPont• Coragen (also in Durivo and Voliam)
– Excellent control of caterpillars– Systemic activity (soil applications)– Adjuvants help foliar applications
(not on all crop labels)– Whitefly activity debatable
Chlorantraniliprole for SLWF
• Vegetable Entomologist Workshop Monterey, California, May 2008
• Best Management Practices for Pest Control in Vegetables
• “Not consistent for whitefly control; suppression at best”
Movento - First Experience• Activity on whitefly (no specifics)• Threw it in a squash test in fall of 2007• Foliar applications at first signs of
silvering• Extreme pest pressure• NOTHING WORKED very well• Had doubts about its activity on SLWF
• Bayer requested greenhouse work
First Impressions
• Movento– Little or no activity on SLWF
• Coragen– Excellent activity on SLWF– Possible replacement for Admire
Greenhouse Studies
• At time of application– Two non-treated plants monitored– Oldest infestation – even mix of small
and large nymphs– Middle infestation – small nymphs +
few eggs– Youngest infestation – recently
hatched nymphs + few eggs
Whitefly per leaf (snap beans) Earliest (oldest) infestation
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Check
Synap
seS+S
ilwet
S+Induce
S+MSO
Movento
Venom
PupaeL. nymphsS. nymphs
Evaluated at 7 DAT
Whitefly per leaf (snap beans) Second infestation
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Check
Synap
seS+S
ilwet
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Movento
Venom
L. nymphsS. nymphs
Evaluated at 10 DAT
SLWF greenhouse Cucumber Test 2 Oldest leaf
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Check
Synap
seSun+
MSO
Coragen
Cor+MSO
Movento
Emerged PLar. Nym.Sm. Nym.
SLWF greenhouse Cucumber Test 2Youngest leaf
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Check
Synap
seSun+
MSO
Coragen
Cor+MSO
Movento
Emerged PLar. Nym.Sm. Nym.
Number of plants with silverleafDrench Treatments - 2006
0123456789
1012
DA
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14 D
AT
21 D
AT
29 D
AT
33 D
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47 D
AT
CheckVenomAdmireCoragen
Transplant drench (Oct. 31, one true leaf); pest pressure light to moderate
Silverleaf RatingsSoil and Foliar Treatments - 2007
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13/7 DAT 17/11 DAT 23/17 DAT 31/26 DAT
CheckVenom (s)Venom (f)Coragen (s)Coragen+ (f)
Soil app. at cotyledon stage, first foliar 6 days later. Bif+Ort 3 times.
Silverleaf RatingsFoliar Treatments - 2008
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3 DAT-1
6 DAT-1
3 DAT-2
1 DAT-3
6 DAT-3
4 DAT-4
7 DAT-4
CheckAssailCoragenCoragen+
Four weekly applications, minor silverleaf at first application.
Squash Silverleaf Ratings (0 to 6)Drench Treatments - 2008
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/200
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9/12
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9/14
/200
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9/16
/200
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9/18
/200
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9/20
/200
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9/22
/200
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9/24
/200
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CoragenVenom1013Check
Treatments applied 8/15/08 and 9/3/08
Current Views• Movento provides excellent control of
early instar whitefly nymphs• Coragen activity may be similar
– Addition of surfactant significantly increases efficacy of foliar treatments (label restrictions)
– Efficacy much better as preventive treatment
– Soil application longer residual
Current Views• Movento and Coragen provide excellent control
of early instar whitefly nymphs– Should be considered in
• product selection• application timing• product evaluation
– Probably not suitable for rescue treatment or stand alone on siesitive crops
– Excellent preventive or rotation partner (unique MOA, highly systemic, long residual)