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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
+
~
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 +
~ -
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
+
-
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