Basic Insect Management :
Field Crops
Doug Johnson
BASIC TRAINING FOR CROP PRODUCTION 2006
Integrated Pest Management
Feb. 7 – Winchester
Feb. 8 – Elizabethtown
Entomology
Feb. 9 – Princeton
Before you do anything else
• Make sure the pest is
correctly identified!!
Many Ways to Organize
• Note the “PAMS” approach
• Adopted by USDA as ‘the” approach
• Likely to play a large role in goal setting,
evaluation (and regulation?)
The PAMS Approach
IPM
• Prevention,
• Avoidance,
• Monitoring,
• Suppression
Prevention
• Keep the pest out of the field!
– Legislative; control movement of plant material
and soil
– Cultural; use pest free seed / transplants
– Management; prevent weeds from producing
seed
– Mechanical; mow European corn borer staging
sites in spring.
Prevention
KY Examples
• Pest free transplants (Tobacco)
– KY Production
– Import restrictions e.g. plants from south?
• Reduce soil movement (soil insects)
• Pest free seed
• Clean equipment (especially in stored grains)
Avoidance
• Crop Rotation
• Nutrient Management
• Planting Date
• Timely Harvest
• Uniform Planting
• Avoidance of Loss of
Value
• Maturity groups
Immigrant Insect Pests
• Alfalfa
– Potato leaf hopper
• Corn + Grain Sorghum
– Black cutworm, Fall armyworm
• Soybean
– Soybean aphid
• Wheat
– Grain aphids
Potato leafhopper
Adults MIGRATE north in spring - lay eggs in
alfalfa. Winter management techniques or
severity not effective.
Avoidance
• Crop Rotation
– Corn - corn rootworm
Avoidance
• Planting Date
– Alfalfa –potato leaf hopper, fall seeding
– Corn - corn borers, fall armyworm
– Soybean - Soybean aphid, soybean podworm
– Wheat - Hessian Fly,
– Grain Sorghum - Sorghum midge
Avoidance
• Uniform Planting
– Grain Sorghum – Sorghum midge
– Tobacco – aphids and corn earworm (especially in seed
production)
Avoidance
• Maturity groups
– Corn – Fall armyworm
– Wheat – Cereal leaf beetle
– Soybeans – Soybean podworm
– Grain Sorghum – Sorghum midge
Avoidance
• Nutrient Management
– Soybean aphid and K deficiency
– Aphids and over use of N2
Avoidance
• Timely Harvest
– Alfalfa – potato leafhopper, cut every 30 days
• Alfalfa weevil harvest to avoid spraying.
Avoidance
• Harvest to Avoid Loss of Value
– Corn – corn borers - harvest before lodging.
– Soybean – soybean stem borer, harvest before
lodging.
– Alfalfa – blister beetles, sell first 2 cuttings as
blister beetle free.
Monitoring
• Crop Scouting
• Damage Assessment
• Trapping
• Modeling
Prediction
(PAMS Monitoring [part])
• Estimating occurrence of new pest.
– Example soybean aphid
• Estimating occurrence of occasional pests
– Example southwestern corn borer
• Estimating occurrence of annual pests
– Example arrival of black cutworm or appearance
of armyworm
Detection
(PAMS Monitoring)
Scouting (DIRECT)
– Direct plant examination for pest or damage
– Soil sampling wireworms, white grubs etc.
• Trapping (INDIRECT)
– insect pheromone traps (many moths)
– Sticky / color traps (aphids)
• Damage Assessment (AFTER THE DAMAGE)
What will you probably see first?
Stems broken just a few
inches above ground
You can not see a tunnel
on either side of the break
Notice the “beveled”
edge of the stem
Overwinter SWCB Survival
Caldwell, Henderson, Davies, Hardin Counties
Four fields/county
Year
SWCB Survival
SWCB/stalk
1999
2000
2001
2002
2003
2004
2005
10.1
26.9
9.7
5.3
4.3
2.5
5.3
3.64
5.57
3.92
0.63
1.13
0.39
0.30
Prediction
(PAMS Monitoring [part])
• Using:
– predictive models,
•
http://wwwagwx.ca.uky.edu/Gisproducts.html
– weather / climate patterns,
– traps example spore traps or insect traps,
– sentinel or trap crops,
Monitoring
leads to
Decision Making
• Research based tools
• Experience based estimations
Economic Thresholds
vs
Economic Injury level
Number
Of
Pests
-OrDamage
Level
EIL
ET
Time or Plant Stage etc.
How do we decide?
• Economic Injury Level (EIL) – The point at
which the cost of injury becomes greater than
the cost of control.
• Economic Threshold aka Action Threshold (ET)
– The level at which action should be taken.
Economic Thresholds
by Plant Stage
ET
Defoliation
Maturity
Vegetative
Seedling
Reproductive
Plant Stages
For example soybean aphid on soybean
• Action Threshold is:
– 250 aphids per plant,
– Plants in V through R5 stages,
– Provides one week to make application.
To use the threshold you must have data
from the field
• Plant growth stage
• Number of insects present.
Suppression
• Biological
• Host Plant Resistance
• Mechanical
• Chemical
Remediation
(PAMS Suppression)
•
•
•
•
Biological (natural enemies)
Cultural (planting date, host plant resistance)
Mechanical (cultivation)
Chemical (pesticides)
Natural Control
Biological Control
• Conservation
– If you don’t spray when you don’t need to
then you practice this! e.g. preservation of
lady beetles, syrphid flies, parasitoids.
• Augmentation
• Importation (Classical)
– Asian lady beetle
Host Plant Resistance
• Modern hybrid field Corn
– DIMBOA (European corn borer)
– Gray leaf spot resistance
• Soybean
– Soybean cyst nematode resistance
• Wheat
– Hessian Fly resistance
Mechanical
• Stalk / Stem destruction
– Crown displacement - Soybean stem borer
– Mowing staging sites - European corn borer
Chemical
Active ingredients
• Synthetic Compounds
– Many families
• Formulated Pathogens
– Bacillus thuringensis, e.g. Dipel
– Spinosad, e.g. Naturalyte, Tracer
• Botanicals
– Nicotine sulfate
• Soaps and Oils
Chemical
Deployment
• Soil applied
• Foliar applied
• Seed coatings
• Transgenic
So, Where Do They Fit?
• Where are they needed?
• Were will they work?
• Where are they economical?
Yield Benefit by Planting Date
7-Year Average
Planting Date
Non-Bt
Tunneling
(in)
Early – Mid April
3.2
Yield, nonBt
(bu)
189.7
Yield,
Diff.
(bu)
3.2
Late April
4.0
198.8
2.7
Early –Mid May
4.1
182.3
6.2
Late May
5.2
160.2
9.2
Early – Mid June
6.3
112.3
21.1
Insects Controlled by Bt Corn
ECB
SWCB BCW
FAW
CRW
YieldGard CB
++
++
-
+
-
YieldGard RW
-
-
-
-
++
YieldGard Plus
++
++
-
+
++
Herculex 1
++
++
++
++
-
Herculex RW
-
-
-
-
++
Herculex Xtra
++
++
++
++
++
Traditional Corn Seed Treatments
‘Hopperbox’
Agrox Premiere
Germate Plus
Grain Guard Plus
Kernel Guard
Kernel Guard Supreme
KickStart
Lorsban SL
True Seed Treatments
Seed Treatments (Ordered with seed)
– Imidacloprid
Gaucho extra
Prescribe
(0.6 mg/kernel)
(1.34 mg/kernel)
– Thiamethoxam
Cruiser Extreme Pak
(0.25 mg/ker)
Cruiser Extreme Pak CRW
(1.25 mg/kernel)
– Clothianidin
Poncho 250
Poncho 1250
(0.25 mg/kernel)
(1.25 mg/kernel)
Insects Controlled
WW
WG
FB
SCM BCW CRW
Gaucho
++
++
+
++
-
-
Prescribe
++
++
++
++
-
+
Cruiser Ex Pak
++
++
++
++
+
-
Cruiser EP CRW
++
++
++
++
+
++
Poncho 250
++
++
++
++
+
-
Poncho 1250
++
++
++
++
++
++
Immediate Plant Back
30-Day Plant Back
120-Day Plant Back
12 Month Plant Back
Making the Control Decision
• Rotation information
– Corn after corn ? After pasture ?
• Planting Date
– Very early - wireworms
– Very late – corn borers
• Likelihood of Problems
– Past problems ?
• Cost
– Is rotation more cost effective?
• Equipment
Soybean
Seed Treatment Test Results over three
years
• In NO trial did any treatment ever yielded
differently from the untreated check.
• In all cases insect populations were minimal.
• In no year was movement of plant virus
important.
How many ways can you make a
mistake?
• Treat when you don’t need to treat,
– Lost cost of application & increased risk of
environmental, regulatory burden
• Treat when you do need to treat,
– Reduced your losses but at a cost,
• Don’t treat when you do need to treat,
– Loss of potential yield / quality, thus income
• Don’t treat when you don’t need to treat.
– Conservation BioControl
Secondary Outbreak
16
Application
14
12
10
Primary Pest
Seconday Pest
8
6
4
2
0
1
2
3
4
5
6
7
8
9
Time or Plant Stage Etc.
0
Resurgence
14
Pesticide Application
12
10
8
Pest Counts
6
4
2
0
1
2
3
4
5
6
7
8
9
0
Time or Plant Stage Etc.
Why does this happen?
Insecticide
applied
Pest population
declines, but can
rebound
Natural
enemies crash
and can not
rebound
RESISTANCE
• Resistance has been documented in every class of
insecticides involving more than 500 insect and mite
species
56% are crop pests
39 % are med/vet pests
5 % are beneficial species
Resistance is most common in ...
• multivoltine pests – several generations per year
• pests exposed to multiple sprays each season or
extended-release applications
RESISTANCE
Tactics that will not work!
• Spray more often (or constant availability)
• Use a higher concentration of the pesticide
These tactics may give some short term
relief, but will cause the problem to get
worse!!
RESISTANCE
Not limited to pesticides
• Western corn rootworm in corn
– Central IL, IN & OH
– For years rotation mainstay of management
– WCR now laying eggs in soybean!
Two General Impacts
• Short Term – will the treatment impact on
the yield pay for the cost of treatment?
• Long Term – Will use of the treatment result
in its loss, reduce its availability, increase its
cost, or increase its regulation?
Management Summary
•
•
•
•
•
•
•
Identify the problem
Understand the problem
Measure the problem
Make a decision (or plan)
Apply control tactic
Evaluate tactic
Modify or repeat as necessary