there is a new paradigm in seed treatments for corn and soybeans · 2016-02-19 · there is a new...
TRANSCRIPT
Insect Insights:
There is a new paradigm in seed
treatments for corn and soybeans
Gilles Quesnel
Independent Agronomist, Winchester
New Neonicotinoid Seed Treatment Regulation
• New class of pesticides - Class 12 for corn and
soybean seeds treated with imidacloprid,
thiamethoxam and clothianidin (Neonics).
• New regulation introduced to ensure that neonicotinoid-
treated corn and soybean seeds are used only when
there is a demonstrated pest problem.
• Integrated Pest Management approach.
What is IPM?
• Integrated Pest Management
• Official term came into use in 1970s but approach
started back in the 1950s 6000 BC
• A systems approach to pest control that uses all
available technologies to efficiently and economically
reduce the pest population while respecting health and
the environment
• Continuously evolving as science improves on pest
knowledge, monitoring tools and control options
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
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
Misidentification Leads to Unnecessary
Applications
2014
Wireworm species by soil texture class
0
10
20
30
40
50
60
70
80
90
100
Clay Clayloam
Loam Loamysand
Sandyclayloam
Sandyloam
Silt loam Silty clayloam
Pro
po
rtio
n o
f to
tal
wir
ew
orm
s f
ou
nd
(%
)
Soil Texture Class
Limonius agonus
Hypnoidesabbreviatus
Agriotes mancus
Hemicrepidius sp.
Melanotussimulis/cribulosus
Melanotuscommunis/dietrichi
Aeolus mellillus
2014
Wireworms found associated with time
of sampling
0
10
20
30
40
50
60
70
80
90
100
WWM trap(before
emergence)
WWM trap(VE-V1)
VE-V1 V2-3 V4-5 V6-7 V8-V11
Pro
po
rtio
n o
f to
tal
wir
ew
orm
s f
ou
nd
(%
)
Crop stage at time of sampling
Limonius agonus
Hypnoides abbreviatus
Agriotes mancus
Hemicrepidius sp.
Melanotussimulis/cribulosus
Melanotuscommunis/dietrichi
Aeolus mellillus
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
Easy Scouting = Easier Management
• The easier it is to scout for a pest, the easier
it is to apply a control strategy when needed
• Much easier to find above ground pests
– eg. Bean leaf beetle and soybean aphids
10
Soil Pests are Complicated
• Harder to find below ground pests
• Good understanding of grubs and life cycle
• Seedcorn maggot tough to scout for until
damage is done
• Still much to learn about wireworms which
are not easy to scout for
• Lack of easy, accurate scouting methods
leads to the use of pesticides as insurance
11
Trapping/Monitoring Improvements
• Research always working towards improving
trapping/monitoring methods
• Learning more about wireworm bait dynamics
• But still needs improvements
• Potential for monitoring of adult click beetles with
traps
– Current pheromone lures for European species
only which are not prevalent in Ontario yet
12
Bait Type and Location
Differences
Flour
Grain
Potato
0
10
20
30
40
50
60
edgefield
grass
• Flour and grain baits were not significantly different but
potato baits had the lowest success rate
• Bait traps along the fields edge were more successful
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
Need Threshold Improvements
• Many are action thresholds and decades old
– do not take into consideration the cost of control,
effectiveness of control options or commodity price
• Tend to have more reliable thresholds for new
emerging/invasive pests since research is very
recent – soybean aphids
• Meaningful thresholds for below ground pests are
extremely challenging to develop and use.
• Not many thresholds that take into consideration a
combination of pests attacking the crop at once
– Soybean defoliation threshold being the exception
15
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
Challenges in IPM
• Usually looks at one pest/one crop at a time
• Challenging to consider all pests/cropping systems
approach
• Hard to predict all impacts each approach has on
non-targets and secondary pests
• Perception that organic products or biocontrol do not
have negative impacts on environment
17
Cultural Control
• Crop rotation has limited impact, given
grassy weeds present along fields edge
• Tillage can help reduce population levels
– However, timing when larvae are at surface key
– Need 3 or 4 passes to see some effect
– Negative impacts to soil health
– Not selective – can impact natural enemies too
18
Pros and Cons to Biocontrol
• Usually a lag time before biocontrol agents build up
• Require ideal field conditions
• Some are not long lasting (eg. nematodes and
entomopathogens)
• Very costly if application required (no mass
production of biocontrols)
• Easily killed with pesticide applications
• Some are not selective
– eg. nematodes impact bumble bees and other soil
nesting bees
19
20
Wireworm infected with Metarhizium spp.
T Kabaluk AAFC
Entomopathogenic nematodes used for grub control.
Dave Cappaert, MSU, Bugwood.org
Entomopathogenic Nematodes
Impact on Bumble Bees
21
Entomopathogenic nematodes used for grub
control. Dave Cappaert, MSU, Bugwood.org
Dutka A, McNulty A, Williamson
SM. (2015) A new threat to bees?
Entomopathogenic nematodes
used in biological pest control
cause rapid mortality in Bombus
terrestris. PeerJ 3:e1413
https://doi.org/10.7717/peerj.1413
IPM Challenges
• Traditionally seed treatment as an ‘insurance policy’
without identification of a target pest appears to run
counter to the basic principles of IPM.
• Yet we do it a lot. Especially with fungicide seed
treatments. What about Bt corn, RNAi, or traditional
crop resistance?
• Is targeted “insurance” legitimate IPM?
22
seed treatments
23
24
Harmful to honeybees when used
on some crops but not all crops
Comments Within Document
• The preliminary risk assessment identified a residue
level for imidacloprid of 25 ppb
– Below this level – effects are unlikely
• Data show that citrus and cotton may have residues
in pollen and nectar above the threshold level. Other
crops such as corn and leafy vegetables either do
not produce nectar or have residues below the
PMRA/EPA identified level
• Assessment only pertains to honeybees. It does not
consider native bees (eg bumble bees)
25
No potential risk to bees was indicated
for seed treatment use.
• The exposure route of dust generated during
planting of treated seed was also considered. Dust
generated from planting of neonicotinoid treated corn
and soybean seed was previously identified as a
concern in Canada, and risk reduction measures
were put in place in 2014 to reduce exposure to dust
during planting of treated corn and soybean seed.”
26
Neonicotinoid seed treatments
What did we learn?
Acknowledgments: Dr. Art Schaafsma, Dr. Victor Limay-Rios,
Dr. Yingen Xue, Tracey Baute Jocelyn Smith, Gabriel Forero Todd Phibbs, Darrel Galbraith
Jen Bruggeman
Neonics in vacuum planter exhaust during planting
0.0029 to 0.11 g ai/ha in exhaust
00.05 to 7.69 % from soil dust
92 to 99.95 % from seed
0.01 to 0.44 % of seed applied neonic
Source of >>92 % of neonics moving
in and around corn fields Xue, Y., Limay-Rios, V., Smith, J., Baute, T., Forero, L. G., & Schaafsma, A. (2015). Quantifying Neonicotinoid Insecticide Residues Escaping during Maize Planting with Vacuum Planters. Environmental science & technology, 49(21), 13003-13011. DOI: 10.1021/ acs.est.5b03753
The problem: seed abrasion in vacuum planters Two key sources - Talc - Field Dust 13 lbs/a of abrasive dust going through vacuum system
98% comes from field through intake
Solution: Pre-filter followed by post filter
Vacuum Planter
vacuum
exhaust deflector engaged
vacuum
line
seed
disk
exhaust
deflector
vacuum
exhaust sample bags
engaged
vacuum
intake
Goal for all seed treatment pesticides - reduce residue escape by > 95%
1. Pesticide applied stays on seed
2. Filter/re-direct exhaust dust INTO soil
3. Vacuum intakes – clean air
4. Non-abrasive seed lubricants
5. Conservation tillage
Conflicting Perspectives of Value
• Insurance - risk/benefit?
– economics
• Yield
seed treatments
Corn Yield Response
to Neonic Seed Treatment 2015
Cooperator: Bycrest Farms
Hybrid: Dekalb DKC 50-78
Previous Crop: Soybeans
Pricing: Corn - $5/Bu
Treatments Yield (Bu/a) Ave. Yield Yield Diff. Net $/acre
Neonic 236 236 + 7 Bu/a + $35
Fungicide 230 229
Neonic 236
Fungicide 225
Neonic 236
Fungicide 231
Corn Yield Response
to Neonic Seed Treatment 2014
Treatments Bu/Acre Diff. Bu/acre
Check 172
CruiserMaxx 250 172 - 2 Bu/ac
CruiserMaxx 250 168
Check 168
Check 170
CruiserMaxx 250 163
Cooperator: Cedar Lodge Farms
Planted: May 21, Harvested Dec 1st
Hybrid: Mycogen 2J337, Previous Crop: Corn
New Seed Treatment Products Corn
• Insecticide Seed Treatments
– Chemical Group 28 - diamides
• Fortenza (Syngenta)
– Active ingredient: cyantraniliprole
– Cutworm, wireworms and European chafer grubs
• Lumivia (DuPont)
- Active ingredient: chlorantraniliprole
- Potential registration in spring 2016
- Wireworms, grubs, cutworm, seedcorn maggot (suppression)
36
• Less systemic than neonics
• Less water soluble
• Very effective on lepidoptera (caterpillars) and some fly
and beetle larvae
• Rate dependent efficacy on other soil pests
38
Group 28 – Diamides
Group 28 – Diamides
• Products already used:
–cyantraniliprole: Lumiderm (seed treatment)
–chlorantraniliprole: Coragen, Voliam Xpress
• Excellent mammalian, bird, fish, earthworm etc safety
• Relatively low impact on beneficials (some exceptions)
• “Reduced Risk” but this doesn’t mean “No Risk”
Coragen Bee LD50 Oral = 118 ug/bee
Bee LD50 Contact = 82 ug/bee
clothianidin Bee LD50 Oral = 0.0038 ug/bee
Bee LD50 Contact = 0.044 ug/bee
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Fortenza Label
• Toxic to bees. This product is systemic and bees can be
exposed to product residues in flower, leaves, pollen
and/or nectar resulting from seed treatment applications.
However, when this product is applied and used
according to label directions, risk to bees is expected to
be negligible
• Follow best management practices to help minimize dust
exposure to pollinators during planting of treated seed;
refer to the complete guidance “Pollinator Protection:
reducing risk from treated seed” on the Health Canada
website (www.healthcanada.gc.ca/pollinators)
40
Can Seed Treatments Fit in IPM
Yes, if:
We fix the problem with dust escaping the planter for
ANY seed treatment
We can be proactive and minimize the off target
exposure
Move towards using reduced risk products
Low to no impact on non-targets
Low to no residues in pollen or nectar
≠ But wall to wall use leads back to increased risk
41
For 2016
• Take IPM Course for corn and soybeans
• Consider doing on-farm seed treatment trials
– Fungicide only
– Fungicide + Neonic
– Fungicide + diamides (e.g. Fortenza)
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Gilles Quesnel Twitter: @GillesQuesnel
Independent Agronomist, Winchester ON 613-294-7977
Thank You