hessian fly id/management in wheat
DESCRIPTION
Hessian Fly ID/Management in Wheat. Jack Baldwin Fangneng Huang Rogers Leonard Steve Harrison Ed Twidwell. Hessian fly Mayetiola destructor. Adults. There are 4-6 generations each year. A generation takes about 35 days at 75 º F, longer at cooler temperatures. - PowerPoint PPT PresentationTRANSCRIPT
Hessian Fly Hessian Fly ID/Management ID/Management
in Wheatin WheatJack BaldwinJack Baldwin
Fangneng Fangneng HuangHuang
Rogers LeonardRogers Leonard
Steve HarrisonSteve Harrison
Ed TwidwellEd Twidwell
Adults
Hessian fly Mayetiola destructor
•There are 4-6 generations each year.
•A generation takes about 35 days at 75 º F, longer at cooler temperatures.
•Development occurs between 40-80 º F
Hessian fly eggs
Hessian fly larvae 2nd stage (L) and 3 stage (R)
Hessian fly puparia
puparia
Larvae R. Ratcliffe Photo
Hessian fly puparia
1 2-3 3-4
Hessian Fly In Wheat
Fly damaged plants and/or tillers
More dead tillers, thin stand
Toxins in saliva cause stunting, plant death, yield and quality losses
A thin stand of stunted plants (right) is a classic symptom of Hessian fly infestation
Hessian Fly In Wheat
Fly damaged plants and/or tillers
John Van Duyn - NC State Randy Weisz – NC State
Hessian fly damage looks different, depending on when the wheat was infested
sometimes a wide leaf blade is a symptom. Often the wide blade has a blue-green hue.
Hessian fly damage looks different, depending on when the wheat was infested
early infestation results in stunting so leaf blades only partially emerge from the ground
Infested tillers often die, particularly when subjected to cold stress in winter
Hessian fly puparia
infested in winter?
infested in spring
Hessian fly yield loss in winter wheat
• Seedling early tiller stage: – 1 larva completely stunts
and kills tiller– Cold injury
• Jointing / Heading / grain fill stage: – Multiple larva per stems at
joints– Stunts stem– Weaken stem cause
lodging.– Reduces grain filling / test
weight.
↓
Hessian fly yield loss in winter wheat
• Seedling early tiller stage: – 5% - 8% infested tillers
• Heading / grain fill stage: – 15% - 20% infested
stems– 10% @ $7.00+/bu
Ryegrass /winter wheat are common for food plots in southern “green fields”.
1998 440-83K acres
2007 613-228K acres
Winter Wheat Acreage and Losses to Hessian Fly in Georgia (1972-2007)
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200
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1600
1972
1974
1976
1978
1980
1982
1984
1986
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1990
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1994
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1998
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2006
Ha
rve
ste
d a
cre
s (
x1
00
0).
0
1000
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3000
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5000
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7000
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9000
10000
$ L
os
se
s
Acreage $ Losses
Hessian fly outbreak years
$28M
Wheat Hessian Fly Management Summary
for Georgia
David BuntinDept. of EntomologyUGA – Griffin Campus
2008
Hessian ‘fly-free’ planting dates to avoid fall damage
Effect of Spring Tillage on Hessian Fly Emergence from Wheat Stubble(From Chapin et al. 1992. J. Entomol. Sci. 27:293)
0
5
10
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25
30
Hes
sian
fli
es p
er t
rap.
.
No-till Burn Disk Burn &Disk
Plow
aab
bc
c
d
Hessian fly Suppression (Wheat Stubble Management)
• Plant as far away from previous year’s wheat stubble as possible.
• Bury stubble to prevent emergence.• No-till = burn alone > disking > plow.• Burning stubble will not kill pupae.• Plant resistant varieties in previous years field.
Control Volunteer Wheat
Only important alternate host in GA is little barley, Hordeum pusillum
No-till Soybeans with volunteer wheat
DO NOT use susceptible wheat for wildlife plots or as a cover crop
Hessian Fly Parasitism in Winter Wheat in Georgia – 1986/1987
Sample
Period
Parasitoid
Species
% Parasitism
North GA South GA
October P. hiemalis 9 0
January P. hiemalis 27 4
March P. hiemalis 57 4
May H. destructor
E. allynii
23 5
Plant Resistance for Hessian Fly Control
When a population of Hessian flies overcomes the host plant resistance, it is called a biotype.
Numerous plant resistance genes have been identified for Hessian flies. As they are deployed, new biotypes emerge.
It is important to know what biotypes are present in order to choose the right Hessian fly "resistant" variety
Hessian Fly Biotype Composition in Southern Georgia (1986-2000)
0%10%20%30%40%50%60%70%80%90%
100%
1986 1989 1991 1996 2000 2008
EGMOLOther
Sources: R. Ratcliffe et al., USDA-ARS, Purdue Univ.
?
Other
Biotype L
Biotype O
Percent:
Poplarville 1996L, D, J
Roger Ratcliffe, now retired from the USDA Hessian fly lab
Hessian fly biotypes 1996-2001
Insecticides for Hessian Fly
• Gaucho 600– 0.8 to 2.4 fl. oz. / 100 lb
• Gaucho XT– 3.4 oz/100 lbs seed– Raxil & Apron fungicides– Rate too low for HF
• Gaucho XT + Gaucho 600 @ 1 oz/100 lb seed
• Commercial seed treater– Seed conditioner, dealer
• Cruiser 5FS (Wheat-Pak)– 1 oz/100 lb seed– Contains 3 fungicides– Rate too low for HF– Max. 1.33 oz/100 lb seed
• Karate Z (1.92 oz/A) – @ 2-4 leaf stage. – @ full tiller (early to mid March)– Suppression; Timing difficult
Di-Syston 15G and Thimet/Phorate 20G are no long labeled for use on wheat.
Hessian Fly Control by Insecticide Treatments (Plains, GA)
0
5
10
15
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35
1994/1995 1995/1996 1996/1997
% I
nfes
ted
Til
lers
Untreated DiSyston 15G Gaucho 600 @0.8Gaucho 600 @ 1.2 Gaucho 600 @ 1.6 Warrior @ 30DAP
**
*
**
*
*Significantly different from Untreated, P = 0.05.
Early spring Hessian fly control with insecticide in fall infested
wheat
Early spring Hessian fly control with insecticide in fall infested
wheat
Treatments* Eggs/10 leaves** HF/5 plants*** Bu/acre
• [email protected] oz 12.3 c 41.2 c 48.2 a
• Warrior@ 3.8 oz 5.0 c 23.3 c 56.7 a
• [email protected] oz 2X 8.0 c 16.2 c 58.1 a
• Untreated 32.3 b 131.8 a 17.7 b * Sprayed 3/13; ** on 3/20; *** on 4/6
JVD
Hessian Fly Management Tactics
• Rotate wheat if possible. • Control volunteer wheat. • Do not use susceptible wheat as cover crops/wildlife plantings.• Conventional tillage (fall and spring).• Plant at recommended times.• Variety selection.
– Plant resistant varieties (if possible).– Plant susceptible varieties ‘only’ in new fields.
• Insecticides use strategies– Seed treatments – Lambda cyhalothrin - scouting for late winter suppression.
For Grazing: only oats, rye, ryegrass.
Questions?