2014 Soybean Insect Update

1. 2014 Soybean Insect Update Dominic Reisig NCSU Entomolgy Photo: Jeremy Greene

2. Content • Insecticidal seed treatments in soybean • Soybean portal • Online threshold calculators • Corn earworm in flowering soybeans • Kudzu bug update

3. Seed Treatments- All contain neonicotinoid-class insecticides Soybean • imidacloprid • Gaucho, Trilex 6000, Acceleron • Aeris (+ thiodicarb) • thiamethoxam • Cruiser Maxx • Clariva Complete (+ nematicide) • clothianidin • NipsIt INSIDE • Poncho/VOTiVO (+ thiodicarb + Bacillisfirmus) Cotton • imidacloprid • Gaucho, Acceleron I • Aeris (+ thiodicarb) • thiamethoxam • Cruiser • Avicta Duo, Acceleron N (+ abamectin) • clothianidin • Poncho/VOTiVO (+ thiodicarb + Bacillisfirmus)

4. Insecticide Seed Treatment Adoption in Beans

5. Neonicotinoid seed treatments, soybeans, and slugs

6. Costs of neonicotinoid seed treatments Slugs activity density were larger with seed treatments Mixed ANOVA: Seed treatment, F1,5 = 26.5, P < 0.01

7. Costs of neonicotinoid seed treatments Seed treatment reduced pitfall catches of some predators June 12th * P = 0.12 * #/trap * * P < 0.05, Mixed ANOVA No significant differences for: Ants, wolf spiders, sheet web spiders, harvestmen, or predaceous beetle larvae

8. Soybean Seed Treatments As of 2013 in Virginia and North Carolina 15 seed treatment tests Five foliar treatment tests NO YIELD ADVANTAGE It is not worth using an insecticidal seed treatment

9. soybeans.ces.ncsu.edu

10. Thresholds now on soybean portal! soybeans.ces.ncsu.edu also linked to nccrops.com Click “Insect Management” Click “Thresholds” Under corn earworm thresholds click “threshold calculator” Also an online stink bug threshold calculator

13. WHAT ABOUT CORN EARWORM IN FLOWERING BEANS?

14. Corn Earworm Larvae Eat Flowers Edgecombe County, NC 2012 Low Moderate High Moderate Corn Earworm Pressure

15. No Relationship Between Corn Earworm Larvae Number and Yield at Peak Flowering for 2-3x Podding Threshold Levels

16. Kudzu Bug Update Photo: Jeremy Greene

17. Discovered in 2009 and spreading RAPIDLY

18. 2009 Confirmed 2010 Confirmed 2011 Confirmed 2012 Confirmed 2013 Confirmed MegacoptacribrariaDistribution 2009 – 2013 Map compiled by Wayne A. Gardner, University of Georgia Updated 10 November 2013

19. Selected Reported Host Plants of the Kudzu Bug in Expanded Range Modified from W.A. Gardner and J. Blount, Univ. of Georgia Legumes Non-Legumes Kudzu Soybean Lima Bean Pole/String/Green Bean Lablab Bean American Wisteria Chinese Wisteria Japanese Wisteria American Yellowwood Black Locust Lespedeza Peanut Crimson Clover Clover Alfalfa Sicklepod Fava bean Alligatorweed Cocklebur Cotton Fig Pine Trees Wheat Loquat Wild Blackberry Satsuma mandarin Black Willow Presence ≠ feeding or reproduction Adult occurrence Vs. Reproductive host plants Delayed leaf growth of Amer. wisteria by adult kudzu bugs in spring

20. Adult Choice Test Results Means with the same letter are not significantly different, α = 0.05

21. Adult Field Results Means with the same letter are not significantly different, α = 0.05

22. Nymph Choice Test Results Means with the same letter are not significantly different, α = 0.05

23. Nymph No Choice Results Means with the same letter are not significantly different, α = 0.05

24. 2013 PD & MG (June, V) TREATED UNTREATED

25. 8 September- Midville, GA

26. 31 October- Wayne Co., NC 2012

27. Kudzu bug activity in soybeans across all planting date/maturity groups Adult Nymph May June August Sept.-Oct. July

28. Seasonality 2012

29. Seasonality 2013

30. Adult distribution within the canopy No differences on MG

31. PD & MG 2012 vs. 2013 – Scotland Co.

32. Soybean Genotypes Variation across genotypes: • MG 5 – 8 • Pubescence (color, density, etc) – KY98, KY03 dense pubescens • Leaf shape (round, narrow) – N7103, Vance both narrow • Stink bug, nematode, other insect resistance – NCC05, N94, Manokin • Non-Nodulating - Nitrasoy • PI genotypes & Japanese types - Miyako & Kosamame • Near isogenic insect resistant – Benning lines • Slow wilting – TCPR94, N98, N06, etc. • High protein – N6202

33. Thresholds • Seedling/vegetative soybeans • 5 bugs per plant (adults or nymphs) • Stop using threshold for second generation bugs (generally in July) • Vegetative to reproductive (R7) soybeans • One nymph per sweep (“swoosh” of the net) Preliminary Established

34. Scout Before You Treat • All Stages • Scout at least 50 feet from field edge • If concerned about edge, consider border treatment • Check multiple places in the field • Make treatment decision based on average • Do not rush your decision • Migration takes 6-8 weeks for adults to fully enter field • Sprays do not kill eggs • Consider yield impact of driving over soybeans • Yield loss and development of insect relatively slow

35. Scout Before You Treat • Seedling soybeans • “Peel back” foliage and count insects

36. Scout Before You Treat • Vegetative to reproductive beans (July & later) • Use sweep net • At least 15 sweeps per location • Sweep net does not catch as many nymphs as adults but threshold is calibrated for this • Net will catch small nymphs before you can see large ones on plant

37. Injury resulted from spraying based on visually looking for nymphs. You will spray sooner and avoid this if you sample nymphs with the sweep net.

38. Kudzu Bug Insecticide Efficacy Summary (2010-2012) Preserves some beneficials 2-5 DAT 6-14 DAT

39. Important Points to Remember • Earliest planted/maturing fields highest risk • Scout for nymphs during and after July • Treat at one nymph/sweep (one nymph/“swoosh”) • Do not spray after July based on adult numbers • Migration takes place over several weeks and will result in re-sprays • Pay attention to insecticide chemistry (Do not use cyfluthrin) • Scout for secondary pest flare-ups

40. More info about kudzu bug • Check out the blog and soybean portal: • nccrops.com and soybeans.ces.ncsu.edu • Dominic Reisig • Email: ddreisig@ncsu.edu • Phone: 252-793-4428 x133