Ce diaporama a bien été signalé.
Nous utilisons votre profil LinkedIn et vos données d’activité pour vous proposer des publicités personnalisées et pertinentes. Vous pouvez changer vos préférences de publicités à tout moment.

22. Western Bean Cutworm - Tracey Baute & Jocelyn Smith

253 vues

Publié le

What have we learned in the past ten years? What do we still need to know to better manage this pest.

  • Soyez le premier à commenter

22. Western Bean Cutworm - Tracey Baute & Jocelyn Smith

  1. 1. Western Bean Cutworm Tracey Baute and Jocelyn Smith OMAFRA-Ridgetown, University of Guelph Ridgetown Campus
  2. 2.  Lepidoptera: Noctuidae  Striacosta albicosta (Smith), Arizona, 18871, 2.  Occurred in Colombia, Mexico, SW United States  Outlying records: southern Idaho and Iowa Western bean cutworm Photo by J. Obermeyer, Purdue 1 Smith 1887, 2LaFontaine and Gill 2004
  3. 3. WBC Range Expansion Grey – Original Range Yellow – Expansion since 2000 From: Ecology and Management of the Western Bean Cutworm (Lepidoptera: Noctuidae) in Corn and Dry Beans J Integr Pest Manag. 2010;1(1):A1-A10. doi:10.1603/IPM10003
  4. 4. Larval Behaviour in Corn vs Beans • WBC behave differently in corn vs. beans • In corn, you can see all stages of the insect during the day – Easily find eggs on leaves or larvae in ear later in the season • In beans, only young larvae active during the day. Mid to late instars active at night, moving plant to plant each night to feed. Hide in ground during day – Very difficult to find any life stage on the plant prior to pod feeding/holes appearing
  5. 5. ONE GENERATION PER YEAR
  6. 6. Pupation and Moth Emergence • Larvae drop to the ground in fall to make pre-pupal chamber • Stay all winter in pre-pupal stage • Pupate in soil in May and June • Moths begin to emerge from pupae in Ontario soils in early July (UGRC, 2011-2013) • Emergence occurs earlier upwind from Ontario since traps begin to catch moths in early June • Emergence is staggered, given that trap catches continue for over three months
  7. 7. Pre-pupa in Late Spring
  8. 8. Migrant and Resident Populations • Carried in via weather fronts from neighbouring states, prior to our resident population emerging • Resident moths also fly and get carried across Ontario, into Quebec, NY and Atlantic provinces (PEI and Nova Scotia confirmed in 2017)
  9. 9. Adult Moths • Moths present in Ontario from June until early September, with avg. peak flight in late July • Females emerge first, reach sexual maturity in 4-6 days and mate approx. 3 times • Lay 3- 400 eggs in lifespan • Average lifespan of males and females is 7 and 9 days, respectively
  10. 10. Moths fly at night but you might find them resting in the leaf axils during the day MSU research found that the bulk of moths were flying around between 1 am – 3 am T. Baute, OMAFRA
  11. 11. J. Smith, UGRC WBC Moth Identification • Approximately 2 cm in length • White band along wing margins • Full moon and boomerang markings on each wing • Wing folds over the other, almost lining up with each other at the tip
  12. 12. Realistic encounter with WBC moths – in traps Moths lose the scales on their wings after a few days in the trap– so no markings
  13. 13. Preferred Corn Stage Dry beans preferred, or late planted corn J. Smith et al. 2017
  14. 14. Corn Growth Stage is Key • If there is no tassel inside the whorl, the newly hatched larvae die within a day or two • Eggs laid on young corn plants will die • Focus on fields that at least have a tassel developing inside the whorl • Cues for adults from tassel and silk tissue? • Variable growth stages in fields complicate scouting
  15. 15. WBC Eggs • Egg masses have an average of 50-84 eggs • Longitudinal striations like cantaloupe • Pearly-white when fresh • Hatch in 5 to 7 days (temp. dependant) • Peak egg laying shortly after peak flight
  16. 16. Assessing age of egg mass Day 1 2 3 4 5 6 7 Pearl white Light tan PurpleDark tan Hatch C. DiFonzo, MSU
  17. 17. Larvae • Goes through 6 instars in approx. 30 days • ~2 mm (1st) to ~34 mm (6th) in length • Initially feed on their eggshell, then can only survive on tassel, pollen (flower), silks or kernels (pod and seeds) – little to no leaf feeding • Not cannibalistic – can have multiple per ear • Actively move from plant to plant
  18. 18. Last Instars 5th and 6th instars T. Baute, OMAFRA Two distinct bands behind head
  19. 19. 10 feet across rows Larval dispersal Infestations can be spotty!
  20. 20. YIELD AND QUALITY IMPACT
  21. 21. Economic injury by WBC  Yield loss of 3.6-15 bu/ac with one larva per plant  Grain quality loss  Secondary pests  Mycotoxins C. DiFonzo, MSU C. DiFonzo, MSU
  22. 22. The pest complex Western Bean Cutworm Fusarium Ear Rot/Gibberella Ear Rot & Mycotoxins Injury Silk
  23. 23. What are Mycotoxins?  Mycotoxins = toxic metabolites of fungi Mycotoxin Commodity Fungal source(s) Effects of ingestion Deoxynivalenol (DON) (Vomitoxin) Wheat, corn, barley Fusarium graminearum Human toxicoses India, China, Japan, and Korea. Toxic to animals, especially pigs. Fusarium crookwellense Fusarium culmorum Zearalenone (ZEN) Corn, wheat F. graminearum Possible human carcinogen (IARC). Affects reproductive system in female pigs. F. culmorum F. crookwellense Ochratoxin A (OTA) Barley, wheat, and many other commodities Aspergillus ochraceus Suspected by IARC as human carcinogen. Carcinogenic in laboratory animals and pigs. Penicillium verrucosum Fumonisin B1 Corn Fusarium moniliforme plus several less common species Suspected by IARC as human carcinogen. Toxic to pigs and poultry. Cause of ELEM, a fatal disease of horses. Aflatoxin B1, B2 Corn, peanuts, and many other commodities Aspergillus flavus Potent human carcinogens by IARC. Adverse effects in various animals, especially chickens. Aflatoxin B1, B2, G1, G2 Corn, peanuts Aspergillus parasiticus http://www.fao.org/wairdocs/x5008e/x5008e01.htm
  24. 24. Risks associated with mycotoxins in grain  Feed quality  Detrimental effects on livestock  Ethanol production  Initial mycotoxin concentration is concentrated by 3X in DDGS  Trade and marketing implications  Rejection  Downgraded grain  Financial penalties Mycotoxin Commodity Canada Commodity USA Deoxynivalenol (mg/kg=ppm) Uncleaned soft wheat for human consumption 2 ppm Finished wheat products 1 ppm Deoxynivalenol Diets for cattle & poultry 5 ppm Grains and grain by-products destined for ruminating beef and feedlot cattle older than 4 months and chickens (not exceeding 50% of the cattle or chicken total diet) 10 ppm Deoxynivalenol Diets for swine, young calves, & lactating dairy animals 1 ppm Grains and grain by-products (not exceeding 40% of the diet) 5 ppm www.inspection.gc.ca/animals/feeds/regulatory-guidance/rg-8/eng/1347383943203/1347384015909?chap=1#s1c1
  25. 25. Deoxynivalenol (DON) in Ontario corn  Frequent issue in Ontario grain corn DON 2011 2012 2013 2014 2015 2016 2017 <0.5 ppm 75% 85% 84% 66% 75% 48% 69% 0.5-<2.0 ppm 11% 14% 25% 20% 26% 17% ≥2.0 ppm 24% 4% 2% 9% 5% 26% 14% OMAFRA Survey, A. Tenuta and B. Rosser 2017 45% samples > 3ppm
  26. 26. The Disease Triangle Host Environment Pathogen
  27. 27. Fusarium in corn – Silk infection Favourable Conditions: Inoculum source Optimal weather • 24-28°C (75-82°F) • Moisture (rain, dew, fog, humidity) Hybrid susceptibility Optimal infection @ Silk browning http://extensionpublications.unl.edu/assets/html/g2181/build/g2181.htm
  28. 28. Insects and mycotoxins Fall armyworm, corn earworm & fumonisins Sap beetles European corn borer J. Obermeyer, Purdue J. Obermeyer, Purdue P. Porter, TAMU
  29. 29. ECB and DON  Bt corn reduced DON by ~60% when infested with high intensity (>4 cm stalk tunneling) of ECB DON (ppm) 1996 1997 1998 1999 Avg Non-Bt isoline 1.25 0.51 1.15 1.19 0.96 Bt 0.45 0.36 0.69 1.06 0.57 P-value <0.0001 0.02 0.0019 0.51 <0.0001 Schaafsma et al. 2002 Plant Disease
  30. 30. Ralls, Texas, 2017. Vip3A “Lesser Bt” Pat Porter, TAMU
  31. 31. Vip3a - 6 ppm Fumonisin “Lesser Bt” – 208 ppm Fumonisin Ralls, Texas, 2017. Pat Porter, TAMU
  32. 32. Fusarium in corn – Silk infection + WBC
  33. 33. Fusarium in corn – Silk infection + WBC
  34. 34. Insecticide Efficacy  2011: 2 sites with 77 and 85% plants with WBC egg masses  Field-scale plots (3.6 × 18 m), 4 reps, RCBD, Non-Bt or Cry1Ab corn  Applied at early VT (~90% tassel emergence) with high-clearance sprayer  WBC Injury  No significant differences in DON or yield Incidence 72-88% Severity 75-95%
  35. 35. Insecticide Screening Treatment WBC injury DON (ppm) Yield (bu/ac) Rate (g a.i. ha-1) Incidence (% ± SE) Severity (cm2 ± SE) UTC - 57.3 ± 9.03b 1.99 ± 0.257c 1.82 ± 0.528 165.0 ± 8.3 PROLINE 200.0 56.0 ± 9.16b 1.87 ± 0.259bc 2.50 ± 0.725 168.5 ± 8.3 MATADOR 10.0 16.0 ± 5.08a 0.47 ± 0.258a 1.76 ± 0.509 157.5 ± 8.3 MATADOR 22.4 11.0 ± 3.77a 0.13 ± 0.256a 1.55 ± 0.449 159.0 ± 8.3 MATADOR + PROLINE 10.0 + 200.0 11.2 ± 3.93a 0.08 ± 0.296a 1.62 ± 0.468 174.8 ± 8.3 CORAGEN 25.0 25.7 ± 7.26ab 0.85 ± 0.259abc 1.41 ± 0.409 168.5 ± 8.3 CORAGEN 50.0 13.9 ± 4.73a 0.36 ± 0.258a 1.64 ± 0.476 177.9 ± 8.3 CORAGEN 75.0 19.8 ± 6.02ab 0.52 ± 0.258a 1.68 ± 0.487 179.5 ± 8.3 VOLIAM XPRESS 50.0 + 25.0 8.4 ± 2.89a 0.20 ± 0.258a 1.14 ± 0.330 159.0 ± 8.3 DECIS 15.0 13.9 ± 4.48ab 0.23 ± 0.257a 1.85 ± 0.535 182.7 ± 8.3 BELT 105.0 16.4 ± 5.33a 0.36 ± 0.258a 1.35 ± 0.390 177.9 ± 8.3 SUCCESS 39.8 34.5 ± 8.49ab 0.71 ± 0.258ab 1.70 ± 0.493 163.8 ± 8.3
  36. 36. 0 1 2 3 4 5 6 100 120 140 160 180 1 2 3 4 5 6 Bu/ac DON ppm Application timing of prothioconazole (200 g ai/ha) 1 UTC - 2 V16-17 Silk emergence 3 Full Tassel Silking 4 Full Silking Silks fully emerged 5 Full Silking + 5 Days Silk browning 6 Full Silking + 11 Days Silk senescence Full silking Limay-Rios & Schaafsma 2013 Proline
  37. 37. Bt & pesticide efficacy  3 sites × 3 years (2012-14)  4 replications, large plots  Bt: Non-Bt vs. Cry1F vs. Vip3A  Spray treatments = insecticide and/or fungicide & application timing: Trt Insecticide Timing Fungicide Timing 1 None - None - 2 Voliam Xpressa Early VT - - 3 Coragenb Early VT - - 4 Voliam Xpress VT/R1 Prolinec VT/R1 5 Coragen VT/R1 Proline VT/R1 6 - - Proline R1 (Full silking) 7 - - Headlined R1 (Full silking) 8 Voliam Xpress Early VT Proline R1 (Full silking) achlorantraniliprole (50 g a.i. ha-1), bchlorantraniliprole + £-cyhalothrin (25 and 50 g a.i. ha-1), cprothiconazole (200 g a.i. ha-1), dpyraclostrobin (100 g a.i. ha-1) 419 420 213 214 5 4 407 408 5 4 301 302 7 6 1 2 8 7 6 321 322 323 324 3 4 7 405 406 2 8 47 7 8 3 4 5 6 315 316 1 3 318 2 312 5 6 7 18 4 218215 216 217 306 7 8 2 8 303 304 305 8 42 48 224 782 409 410 411 412 421 422 423 424 401 402 403 404 2 8 413 414 416 6 415 5 418 1 417 3 B o r d e r B o r d e r 45 27 11 9 3 21 3 1 2 1 5 4 23 15 35 33 39 14 20 30 26 8 6 317 1 313 314 6 5 319 320 4 3 307 2 308 309 32 310 311 5 6 3 38 44 219 24 220 221 40 222 223 1 207 10 208 209 4 210 211 22 212 3 1 2 1 5 4 34 28 12 7 6 206 2 8 3 4 7 6 201 46 202 203 16 204 205 36 118 6 5 4 5 8 7 124 8 7 8 2 4 117 41 119 37 120 121 43 122 123 17 3 107 13 108 109 7 110 111 113 25 114 115 19 116 101 1 102 103 31 104 1 2 6 7 112 4 3 1 3 1 2 106 5 5 105 29 6
  38. 38.  Lower incidence of WBC injury on VIP (~10%) than non-Bt and Cry1F hybrids (~30%)  No treatment effects for Vip3A hybrid  No difference between non-Bt and Cry1F  Non-Bt and Cry1F  Incidence ↓ 55-75%  Severity ↓ 82-90%  No difference due to tank mix or timing % Severity of WBC injury (SE) Treatment Timing 35F Non-Bt/ Cry1F P0621 Non-Bt/ Cry1F N46U Vip3A UTC - 0.23 (0.142) 0.57 (0.273)c 0.03 (0.013) VOLIAM XPRESS Early VT 0.12 (0.077) 0.05 (0.025)a 0.05 (0.021) CORAGEN Early VT 0.17 (0.104) 0.08 (0.039)ab 0.03 (0.013) VOLIAM XPRESS + PROLINE VT/ R1 0.09 (0.057) 0.10 (0.045)ab 0.01 (0.006) CORAGEN + PROLINE VT/ R1 0.16 (0.077) 0.16 (0.077)abc 0.03 (0.012) PROLINE R1 0.18 (0.112) 0.22 (0.112)abc 0.05 (0.021) HEADLINE R1 0.23 (0.142) 0.35 (0.164)bc 0.02 (0.010) VOLIAM XPRESS + PROLINE Early VT + R1 0.14 (0.086) 0.05 (0.023)a 0.03 (0.012) Bt & pesticide efficacy
  39. 39. Vip3A Non-Bt
  40. 40.  Treatment effect, no Bt effect  Observed greater reduction in DON with insecticide than fungicide  Low DON levels, fungicide-only treatments may have been applied too late (late R1-R2), silk infection occurred and insect injury not controlled.  No difference in DON due to application timing of insecticide + fungicide Effect on total DON (p<0.05, ANOVA, Tukey-Kramer)
  41. 41. Grain yield Insecticide @ VT: 0-4% Fungicide @ R1: 2-13% Insecticide + fungicide: 4-15%
  42. 42. WBC & mycotoxins  Very complex problem  Environment  Hybrid susceptibility  Hybrid offerings change  WBC injury: incidence>>>severity  Difficult to forecast  Challenging to manage, but WBC control is important  Costly  Tank-mix applied $36.50/ac CAD
  43. 43. TRAPPING AND SCOUTING
  44. 44. Trapping for WBC • Indicate moth presence in a region • Indicate when peak flight and peak egg laying likely • Trap counts do not determine if threshold has been reached (only catching males) • Very important for areas outside the original hot spots to trap • >2500 trap locations over 10 years, captured over 858,000 WBC moths in Ontario!
  45. 45. Ontario Traps
  46. 46. 0 50 100 150 200 250 300 Week 1 Week 2 Week 3 Week 4 Week 5 Week 6 Week 7 Week 8 Week 9 Week 10 Week 11 Week 12 Week 13 Week 14 Week 15 Average#ofWBCMothsCaptured Week Trapped 2017 Ontario WBC Trap Catches Week 1 - May 29 - June 4 Week 2 - June 5-11 Week 3 - June 12-18 Week 4 - June 19-25 Week 5 - June 26-July 2 Week 6 - July 3 - 9 Week 7 - July 10-16 Week 8 - July 17-23 Week 9 - July 24-30 Week 10 - July 31 - Aug 6 Week 11 - Aug 7 - 13 Week 12 - Aug 14 - 20 Week 13 - Aug 21-27 Week 14 - Aug 28 - Sept 3 Week 15 - Sept 4 - 10
  47. 47. 0 50 100 150 200 250 300 350 Week 1 Week 2 Week 3 Week 4 Week 5 Week 6 Week 7 Week 8 Week 9 Week 10 Week 11 Week 12 Week 13 Week 14 Week 15 Average#ofMothsperTrap Trapping Week # Average Regional WBC Trap Catches 2017 Region 1 Region 2 Region 3 Region 4 Region 1 – Essex Region 2 – CK, Lambton, Middlesex, Elgin, Oxford, Haldimand/Norfolk, Brant, Huron Region 3 – Perth, Wellington, Waterloo, Bruce, Dufferin, Peel Region 4 – Grey, Simcoe, Halton, Niagara, Durham, Northumberland, Prince Edward, Lennox & Addington, Ottawa, Prescott & Russell, Stormont, Dundas and Glengarry Week 1 - May 29 - June 4 Week 2 - June 5-11 Week 3 - June 12-18 Week 4 - June 19-25 Week 5 - June 26-July 2 Week 6 - July 3 - 9 Week 7 - July 10-16 Week 8 - July 17-23 Week 9 - July 24-30 Week 11 - Aug 7 - 13 Week 12 - Aug 14 - 20 Week 13 - Aug 21-27 Week 14 - Aug 28 - Sept 3 Week 15 - Sept 4 - 10
  48. 48. 0 50 100 150 200 250 300 Week 1 Week 2 Week 3 Week 4 Week 5 Week 6 Week 7 Week 8 Week 9 Week 10 Week 11 Week 12 Week 13 Week 14 Week 15 Average#ofWBCPerTrap Week Trapped Blue - Some egg laying taking place but unless tassel present, larvae will die. Premature to spray. Majority of eggs still to come during and after peak flight. Yellow- Shortly after peak moth flight is peak egg laying. Target fields in the ideal growth stage and scout for eggs to determine threshold. Peak flight
  49. 49. THRESHOLDS AND MANAGEMENT
  50. 50. Scouting in Corn for WBC • If traps are catching moths, focus on fields in the pre-tassel to full tassel stages • Scout 10 plants in ideal growth stage, in 10 areas of the field (100 plants each time) • Scout every 5 to 6 days, for at least 3 weeks • Count the # of plants with egg masses • Accumulate # of plants over the 3 week period • Be area of variable growth stages in each field. Focus scouting in the areas of the field in the ideal stages
  51. 51. Walk corn rows with plants between you and the sun. Eggs leave shadows!
  52. 52. Chris DiFonzo recommends a face shield to enable fast walking through corn fields while looking up
  53. 53. Adjusted WBC Corn Threshold • Previous threshold and timing were: – 5% of plants scouted with egg masses and/or small larvae (decreased from 8% in Nebraska) – spray at full tassel when majority of egg masses have hatched
  54. 54. Adjusted WBC Corn Threshold • Previous threshold and timing were: – 5% of plants scouted with egg masses and/or small larvae – spray at full tassel when majority of egg masses have hatched • Modified threshold for Great Lakes – cumulative 5% threshold – when 5% of the plants over a two or three week period have had egg masses and/or small larvae – even lower threshold likely needed, if growing a Fusarium susceptible hybrid
  55. 55. Adjusted WBC Spray Timing for Corn • Pre-tassel to full tassel stage has been too early – Prolonged moth flight and egg laying • WBC only feed on tassel, silks and kernels – can’t live on tassel tissue for long • All WBC larvae will head to the ear when present • Instead, spray when fresh silks are present, targeting the ear zone (ground application only?) • Can tankmix with fungicide for ear mould protection at the same time
  56. 56. Products Registered on Corn in Canada • Matador or Silencer (pyrethroid) • 83 – 187 mL/ha • 14 days pre-harvest interval silage, 21 days for field corn • Coragen (diamide) • 250 – 375 mL/ha • 14 day pre-harvest interval • Delegate (spinosyns) • 120 – 210 grams/ha • 28 days pre-harvest for stover, 14 days for forage • Voliam Xpress (pyrethroid + diamide) • 500 mL/ha • 7 days pre-harvest interval • ROTATE chemistries – high risk of resistance with WBC
  57. 57. Transgenic Corn Options • Cry 1F (Herculex or SmartStax) no longer provides protection against WBC • Only hybrids with Vip3A (Viptera) provides control
  58. 58. Evidence for resistance of Western bean cutworm to Cry1F Bacillus thuringiensis protein and transgenic corn hybrids in Ontario, Canada J. L. Smith1, M. D. Lepping2, D. M. Rule2, Y. Farhan1, and A. W. Schaafsma1 1 Department of Plant Agriculture, Ridgetown Campus, University of Guelph, 120 Main St. E., Ridgetown ON, Canada N0P 2C0. 2 Dow AgroSciences LLC, 9330 Zionsville Rd. Indianapolis, IN 46268
  59. 59. SMALL PLOT TRIALS (2011-2014) Year Trmt Plants infested (% ± se) Kernel damage (% ± se) Yield (T/ha ± se) Egg masses Larvae (R3) Incidence Severity 2011 Non-Bt 1.2 (0.52) 11.1 (4.01) 88.9 (3.16)b 3.1 (0.31)b 10.1 (1.15) SSX 1.0 (0.47) 10.2 (3.80 54.5 (5.45)a 1.4 (0.19)a 10.6 (1.15) 2012 Non-Bt 2.9 (1.08) 75.0 (2.85) 85.5 (7.95) 5.3 (0.63) 10.2 (1.93) SSX 5.6 (1.60) 67.7 (3.03) 84.5 (8.18) 6.2 (0.68) 9.5 (1.93) 2013 Non-Bt 3.4 (0.57) 71.9 (6.50) 100.0 5.3 (0.69) 6.6 (1.08) SSX 4.2 (0.63) 52.9 (7.25) 100.0 7.9 (0.53) 7.3 (1.08) 2014 Non-Bt 16.0 (1.82) 35.6 (8.91)b 47.9 (7.55) 2.4 (0.45) 6.3 (0.47) SSX 19.9 (2.13) 6.1 (3.69)a 50.0 (7.56) 2.5 (0.46) 6.6 (0.47) SSX RA 23.1 (2.35) 12.3 (5.30)a 56.3 (7.50) 2.7 (0.50) 6.1 (0.47)
  60. 60. Non-Bt SSX BOTHWELL 2013
  61. 61. Cry1F susceptibility bioassays  Adults collected at black light traps or egg masses from the field in late July 2015  5 locations in SW ON  Dose-response diet-overlay bioassay (Marcon et al. 1999, Dyer et al. 2013)  Truncated Cry1F (53% a.i.) from Dow AgroSciences  Infested with neonates, 24 larvae/conc/rep x 3 reps  F0: 0 to 30,000 ng ai cm-2  Mortality at 7 and 14 d  Weight of surviving larvae at 14 d  F1: 0 to 75,000 ng ai cm-2  Mortality and weight at 7 d
  62. 62. Mortality – F0
  63. 63. Mortality – F1
  64. 64. WBC and Cry1F Collection n LC50 (95% CL) 7 d (ng Cry1F/cm2) Bothwell F0 360 13,032 (6,694-20,093) Ridgetown F0 360 21,197 (12,828-56,660) Dresden F0 360 .a Springford F0 360 11,639 (5,578-19,534) Melbourne F0 360 .a Ridgetown F1 357 72,107 (35,988-39,441,298) Springford F1 480 28,926 (8,487-77,062) a Estimate exceeds the highest concentration tested.
  65. 65. European corn borer and Cry1F Collection n LC50 2 (95% CI) LC95 2 (95% CI) LC99 2 (95% CI) 2016 (ng Cry1F/cm2) Winger (control) 648 4.74 (3.99-5.48)a 16.82 (13.90-21.73)a 28.41 (21.95-40.83)a Oxford 648 4.54 (3.93-5.13)a 12.57 (10.68-15.70)a 19.17 (15.40-26.18)a Simcoe 648 4.70 (4.09-5.33)a 15.73 (13.16-19.89)a 25.94 (20.43-35.89)a Niagara 648 4.53 (3.90-5.17)a 14.46 (12.11-18.31)a 23.38 (18.44-32.52)a Manitoba 648 5.44 (4.62-6.24)a 18.50 (15.36-23.78)a 30.72 (23.87-43.84)a = High Dose
  66. 66. 2016, southcentral MI WBC infested Cry1F fields
  67. 67. John Obermeyer, IPM Specialist, Purdue University “No western bean cutworm control in this Cry1F-expressing corn”
  68. 68. Dr. Andy Michel, Ohio State: “Just plain ugly”
  69. 69. Resistance management for WBC Challenges: • Reliance on 1-2 insecticides • Slow integration of Vip3A into widely used hybrids • Vip3A deployed with a 5% integrated refuge • Almost no effective refuge due to cross-pollination • Extensive inter- and intra-plant larval movement • Exposure of later instars to sublethal doses Solutions(?) • More insecticide options needed • Tank-mixes, rotation program • Stewardship of Vip3A • Abandon integrated refuge • Require insecticide treatment • More high-dose transgenic solutions
  70. 70. Bt pollen flows to “refuge” ears Pat Porter, TAMU
  71. 71. WBC Resources • Field Crop News – up to date, in-season activity • WBC Trap Network – www.cornpest.ca – Interactive Maps – Trapping Instructions – Infosheets for Dry Beans and Corn • Twitter @TraceyBaute, @JocelynLSmith, @JenniferBruggem and @MegnMoran • Pest Manager App • Agronomy Guide, OMAFRA Pub 811 and Field Crop Protection Guide, OMAFRA Pub 812
  72. 72. Thanks to Our Research Collaborators and Sponsors Over the Years

×