Integrated Pest Management

Tracey Baute and Gilles Quesnel OMAFRA

What is IPM?

• Integrated Pest Management

• A systems approach to pest control method that

uses all available technologies to efficiently and

economically reduce the pest population while

respecting health and the environment

• Holistic approach – not just for “Hippies”

Steps In IPM Process

1. Understand the pest (ID, lifecycle, damage,

timing and association with the crop)

2. Conduct field monitoring (scouting)

3. Using injury and action thresholds

4. Least disruptive control strategy

(Cultural, Chemical, Biological, Genetic)

5. Evaluate actions

6. Keep records

Control Strategies

• Preventative Measures

• Cultural

• Genetic

• Biological

• Chemical

Preventative Measures

• Some growers don’t realize that their current

cropping practices are preventative or cultural

control measures for pest control

• Examples include:

– Certified seed

– Sanitation

– Variety/hybrid selection

– Planting timing

– Residue and weed management

– Crop rotation

– Good plant health

Crop Rotation

• most important method to manage pests

– Insects, diseases, weeds

• either removes susceptible crop from field or

takes away primary host of major pest

Crop Rotation

• works best for pests with narrow host range,

those that lay eggs in soil before crop is

planted and less mobile pests

• Examples?

• Best example is rootworm control in Ontario

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Crop Rotation

Rotation Variant

• western corn rootworm have adapted to the

two year crop rotation

• laying eggs outside of corn fields in the US

• not established here in Ontario due to our

three year/more complex crop rotation and

diverse landscape

Cultural Control

Includes:

Mechanical/Physical

Light Traps

Weed Control

Volunteer Crop Removal

Clean Machinery

Remove Residue

Clean Bins

Planting Dates

Crop Rotation

Variety Selection

Good Plant/Field Health

Mowing

Early Harvest

Tillage

Planting resistant

varieties

Sticky Traps

Traditional

breeding

Crop Management

Genetic

Sterile release

Certified Seeds

Potato Leafhopper Management

IPM Options:

– Cultural ?

(Crop Management, preventative)

– Biological ?

– Mechanical ?

– Chemical ?

– Genetic ?

Potato Leafhopper Management

IPM Options:

– Mechanical

• Mowing will:

–Remove damaged plants and

allow regrowth

–Possibly disperse the PLH

• Pros/Cons

Mechanical

• Early harvest for alfalfa weevils, leafhoppers

Tillage +

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Tillage

• removes residue and exposes soil insects to

natural elements

• modifies moisture and temperature of the soil

• tillage for pest reduction needs to be timed

according to pest cycle (doesn’t always work)

• negative impacts may outweigh the pest

control benefits

Genetic Control

• Resistant or tolerant varieties

– SCN varieties, phytophthora resistant varieties

• Genetically modified plants

– Bt corn, RR soys

• Technology can be expensive at first but in

many cases leads to less use of chemical

control

Glandular Haired Alfalfa

• Traditionally bred varieties with high

densities of hairs of leaves and stems

– to physically resist or tolerate leafhopper feeding -

hairs act as barriers

• Not genetically engineered – Selective

breeding for specific desirable traits

Glandular hairs on stem

and leaves

PLH Seedling Damage

Susceptible vs Resistant Varieties

Use of PLH Resistant Varieties

• Resistant plants

– Susceptible (S) < 15%

– Moderately Resistant (MR)15 - 30%

– Resistant (R) - 31-50%

– Highly Resistant (HR) - >50%

Alfalfa Potato Leafhopper

Resistant Varieties

Alfalfa Potato Leafhopper Resistant Varieties

PLH Resistant Alfalfa Varieties

• Glandular hairs on leaves and stems provide

tolerance to PLH

• Treatment thresholds for HR varieties 4X > (after

establishment)

• PLH resistant varieties for:

– area that typically have significant PLH damage

– farmers that do not scout or spray to control PLH

• Pros/Cons

ECB Bt Corn

• ECB was costing US $1 billion annually in

yield losses and control expenditures

• Using high dose of Bt in the plant (99% kill)

• Providing adequate non-Bt refuge, planted in

a way to ensure mating between susceptible

and potential resistant individuals

Success

“Widespread adoption of Bt corn has resulted in an

areawide suppression of O. nubilalis populations,

which has economically benefitted both growers of

Bt and non-Bt corn”

– Siegfried and Hellmich (2012) Understanding successful

resistance management, GM Crops & Food:

Biotechnology in Agriculture and the Food Chain, 3:3, 184-

193, DOI: 10.4161/gmcr.20715

Bt corn Resistant Rootworm

Confirmed resistance issues in Iowa, Illinois, Indiana, Minnesota, Wisconsin,

Nebraska, South Dakota, Missouri, and Kansas.

Suspicious fields in Fringe area of Pennsylvania, Ohio, Michigan, Ontario

and New York.

Cross Resistance

• First registration of CRW Bt corn

– Cry3Bb1 in 2003

• Confirmed resistance:

– Cry3Bb1 in 2010

– mCry3A in 2011 (cross resistance)

Gassman et al. 2014 Field-evolved resistance by western corn

rootworm to multiple Bacillus thuringiensis toxins in transgenic

maize www.pnas.org/cgi/doi/10.1073/pnas.1317179111

What went wrong?

• Low to moderate dose +

• Pyramid traits (eg. SmartStax) +

• Repeated use of the same hybrids and in some

cases lack of refuge compliance +

• Cross resistance means only one trait

(Cry34/35Ab1) still works in pyramid +

• Reduced refuge requirement with pyramids

5 or 10% (Refuge incorporated) +

= hastens resistance

Chemical Control

Pros

• Typically applied at threshold to keep

populations below injury levels

• Quick knockdown

• New products more specific

Cons

• Need to scout and have thresholds

• Potential for resistance, cross resistance, pest

resurgence and secondary pest outbreaks

• Non-target effects

Credit: Dr Peter Sikkema

Pest Resurgence

Secondary Pest Outbreak

Spidermites and Chemical Influences

• pyrethroids (eg. Matador) can cause a mite

population to flare up (kills off their predators

and not the mite)

• foliar fungicides can initiate a mite problem

(kills the entomopathogens)

• Some research indicating neonic seed trts

change plant hormones and actually allows

mites to thrive on these plants

Penn State 2014 – “Toxic Slugs”

• CruiserMaxx Soybeans with NNI seed treatments

create “toxic slugs”

• Slugs are unaffected by neonics but can have as

much as 500ppb in them

• Carry that toxin to their predator (ground beetles)

• Up to 60% of ground beetles intoxicated or killed

Douglas et al 2014

Penn State Research Cont’d

• More slugs present in treated soys versus untreated

• 19% decrease in plant stand and 5% yield decrease

in treated fields due to increased slug populations in

the absence of its predator

“If slugs are the primary pest for your soybean field, you

should not be using NNI treated seed” – Tooker, SWAC

Douglas, Rohr and Tooker. 2014. Neonicotinoid insecticide travels

through a soil food chain, disrupting biological control of non-target

pests and decreasing soya bean yield. Journal of Applied Ecology doi:

10.1111/1365-2664.1

Biocontrol

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Disadvantages to Biological Control

• Slow and may not provide control in an

outbreak year

• Labour intensive when in a threshold

• Can be very specific to one stage of pest

• Harder to maintain in a monoculture crop

• Very sensitive to chemical control and

weather conditions

Cover Crops

• red clover in wheat stubble is ideal for an

overwinter site for spider mites

• grassy cover crops (esp. rye) increase risk of

armyworm, wireworm

• can benefit the natural enemies

Potential Risks

• Rye or grasses in corn & wireworm,

armyworm but benefit for slugs

• Clover in wheat & spider mites

• Plowing down cover crop in spring before

planting = seedcorn maggot issue

Now Available

• Hardcopy and eBook

• Free

• 132 pages

• Describes all Early Season

Pests of Field Crops

• Factors/Conditions that

Increase Risk

• Scouting Techniques

• Thresholds

• Management Strategies

• Natural Enemies and

Pollinator Protection

http://www.gfo.ca/pestguide.aspx

IPM Recap

• Likely already using IPM

• Slightly more knowledge/time intensive in

short run

• Likely time/$$ savings in in long run

Thank You