Basic Insect Management :Field Crops

Doug Johnson

BASIC TRAINING FOR CROP PRODUCTION 2006Integrated Pest Management

Feb. 7 – Winchester Feb. 8 – Elizabethtown

Feb. 9 – PrincetonEntomology

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

• Prevention,• Avoidance,• Monitoring,• Suppression

IPM

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.

PreventionKY 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

• Planting Date

• Uniform Planting

• Maturity groups

• Nutrient Management

• Timely Harvest

• Avoidance of Loss of Value

Immigrant Insect Pests

• Alfalfa– Potato leaf hopper

• Corn + Grain Sorghum– Black cutworm, Fall armyworm

• Soybean– Soybean aphid

• Wheat– Grain aphids

Potato leafhopperPotato 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)

Stems broken just a few inches above ground

Notice the “beveled” edge of the stem

You can not see a tunnel on either side of the break

What will you probably see first?

Overwinter SWCB Survival

YearYear SWCB SWCB SurvivalSurvival

SWCB/stalkSWCB/stalk

19991999 10.110.1 3.643.64

20002000 26.926.9 5.575.57

20012001 9.79.7 3.923.92

20022002 5.35.3 0.630.63

20032003 4.34.3 1.131.13

20042004 2.52.5 0.390.39

20052005 5.35.3 0.300.30

Caldwell, Henderson, Davies, Hardin CountiesFour fields/county

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

ET

EIL

Time or Plant Stage etc.

Number Of

Pests-Or-

DamageLevel

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 Thresholdsby Plant Stage

Economic Thresholdsby Plant Stage

ET

Plant Stages

Defoliation

Seedling

Vegetative

Reproductive

Maturity

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

ChemicalActive ingredients

• Synthetic Compounds– Many families

• Formulated Pathogens– Bacillus thuringensis, e.g. Dipel– Spinosad, e.g. Naturalyte, Tracer

• Botanicals– Nicotine sulfate

• Soaps and Oils

ChemicalDeployment

• 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 Tunnelin

g (in)

Yield, non-Bt

(bu)

Yield, Diff.(bu)

Early – Mid April

3.2 189.7 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

ECBSWC

BBCW FAW CRW

YieldGard CB ++ ++ - + -

YieldGard RW - - - - ++YieldGard Plus ++ ++ - + ++

Herculex 1 ++ ++ ++ ++ -

Herculex RW - - - - ++

Herculex Xtra ++ ++ ++ ++ ++

Traditional Corn Seed Treatments‘Hopperbox’

Agrox PremiereGermate Plus

Grain Guard PlusKernel Guard

Kernel Guard SupremeKickStart

Lorsban SL

True Seed Treatments

Seed Treatments (Ordered with seed)– Imidacloprid

Gaucho extra (0.6 mg/kernel)

Prescribe (1.34 mg/kernel)

– ThiamethoxamCruiser Extreme Pak (0.25 mg/ker)

Cruiser Extreme Pak CRW (1.25 mg/kernel)

– ClothianidinPoncho 250 (0.25 mg/kernel)

Poncho 1250 (1.25 mg/kernel)

Insects Controlled

WWWW WGWG FBFB SCMSCM BCBCWW

CRWCRW

GauchoGaucho ++++ ++++ ++ ++++ -- --

PrescribePrescribe ++++ ++++ ++++ ++++ -- ++

Cruiser Ex PakCruiser Ex Pak ++++ ++++ ++++ ++++ ++ --

Cruiser EP Cruiser EP CRWCRW

++++ ++++ ++++ ++++ ++ ++++

Poncho 250Poncho 250 ++++ ++++ ++++ ++++ ++ --

Poncho 1250Poncho 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

0

2

4

6

8

10

12

14

16

1 2 3 4 5 6 7 8 9 0

Primary Pest

Seconday Pest

Application

Time or Plant Stage Etc.

Resurgence

0

2

4

6

8

10

12

14

1 2 3 4 5 6 7 8 9 0

Pest Counts

Pesticide Application

Time or Plant Stage Etc.

Why does this happen?Insecticide Insecticide appliedapplied

Pest population Pest population declines, but can declines, but can reboundrebound

Natural Natural enemies enemies crash and crash and can not can not reboundrebound

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

RESISTANCETactics that will not work!

• Spray more often (or constant availability)• Use a higher concentration of the pesticide

These tactics may give some short These tactics may give some short term relief, but will cause the term relief, but will cause the problem to get worse!!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