2014 Soybean Insect Update

Photo: Jeremy Greene

Dominic Reisig NCSU Entomolgy

Content

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

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 + Bacillis firmus)

Cotton• imidacloprid

– Gaucho, Acceleron I– Aeris (+ thiodicarb)

• thiamethoxam– Cruiser– Avicta Duo, Acceleron N

(+ abamectin)

• clothianidin– Poncho/VOTiVO (+

thiodicarb + Bacillis firmus)

Insecticide Seed Treatment Adoption in Beans

Year Mississippi North Carolina

2004 0% -

2005 0% -

2006 0% -

2007 2% -

2008 50% -

2009 65% -

2010 70% -

2011 75% 12%

2012 85% 15%

2013 - 29%

VC V1 V30

10000

20000

30000

40000

50000

60000

70000

80000

TU

Plants/acre

Neonicotinoid seed treatments, soybeans, and slugs

T U0

1

2

3

4

5

6

7

June 12th

Slugs/pitfalltrap

Mixed ANOVA: Seed treatment,

F1,5 = 26.5, P < 0.01

Costs of neonicotinoid seed treatments

Slugs activity density were larger with seed treatments

* P < 0.05, Mixed ANOVA

No significant differences for:Ants, wolf spiders, sheet web spiders, harvestmen, or predaceous beetle larvae

Par Wasp Rove beetle Ground beetleOther spider0

2

4

6

8

10

12

#/Pitfalltrap

#/trap

*

P = 0.12

*

June 12th

*

Seed treatment reduced pitfall catches of some predators

Costs of neonicotinoid seed treatments

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

soybeans.ces.ncsu.edu

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

WHAT ABOUT CORN EARWORM IN FLOWERING BEANS?

High ModerateModerateLow

Corn Earworm Pressure

Corn Earworm Larvae Eat Flowers

Edgecombe County, NC 2012

No Relationship Between Corn Earworm Larvae Number and Yield at Peak Flowering for

2-3x Podding Threshold Levels

Kudzu Bug Update

Photo: Jeremy Greene

Discovered in 2009 and spreading RAPIDLY

Megacopta cribraria Distribution

2009 – 2013

2009 Confirmed

2010 Confirmed

2011 Confirmed

2012 Confirmed

2013 Confirmed

Map compiled by Wayne A. Gardner, University of Georgia

Updated 10 November 2013

Selected Reported Host Plants of the Kudzu Bug in Expanded Range Modified from W.A. Gardner and J. Blount, Univ. of Georgia

Delayed leaf growth of Amer. wisteria by adult kudzu bugs in spring

Legumes

KudzuSoybeanLima BeanPole/String/Green BeanLablab BeanAmerican WisteriaChinese WisteriaJapanese WisteriaAmerican YellowwoodBlack LocustLespedezaPeanutCrimson CloverCloverAlfalfaSicklepodFava bean

Non-Legumes

AlligatorweedCockleburCottonFigPine TreesWheatLoquatWild BlackberrySatsuma mandarinBlack Willow

Adult occurrence Vs.

Reproductive host plants

Presence ≠ feeding or reproduction

Adult Choice Test Results

Edamam

e

Soyb

ean

Pigeon pea

Blacke

yed pea

Lab la

b

Hogpean

ut

Fava

bean

FH Li

ma bean

Mung b

ean

Azuki

Bean

Snap

beanPinto

1

Pinto3

Winter p

ea

Chick pea

Tropica

l kudzu

Lima b

eanPinto

2

Peanut

Cage

0

5

10

15

20

25

30

35

40

a

b

cc c

c cc

cc c

c c c c cc

c c

a

a

b

b-c

c-d c-d d d d d d d d d d d d d d dc-d

Days 1-3 Days 11-13

Adu

lt-da

ys p

er p

lant

Means with the same letter are not significantly different, α = 0.05

Adult Field Results

Days 52, 62, and 77 Sweep Samples0

10

20

30

40

50

60

70

80a a

b

cc-d c-d c-d c-d c-d c-d c-d c-d c-d c-d c-d d d d

SoybeanEdamamePigeon PeaMungBeanLimaBeanLabLabPeanutAzukiBeanFavaBeanPinto3Pinto1FH LimaPinto2Blackeyed peaWinterPeaTropicalKudzuSnapBeanChickpea

Cumulative Total 3 out of 4 Sampling Dates

Mea

n A

dults

/10

swee

ps

Means with the same letter are not significantly different, α = 0.05

Nymph Choice Test Results

D1 D2 D3 D4 D5 D6 D7 D8 D9 D10 D11 D12 D13 D14 D150

5

10

15

20

25

30

35 Soybean

Pinto1

Pinto2

Pinto3

WinterPea

Pigeon Pea

Chickpea

FavaBean

SnapBean

LimaBean

Edamame

LabLab

MungBean

AzukiBean

BlackeyedPea

Peanut

TropicalKudzuDays after infestation

Nym

phs

per p

lant

Means with the same letter are not significantly different, α = 0.05

Nymph No Choice Results

D1 D3 D5 D7 D9D11

D13D15

D17D19

D21D23

D25D27

D290

2

4

6

8

10

12

14

16

18 soybean

pinto1

pinto2

pinto3

winterp

pigeonp

chickp

favab

snapb

limab

blackp

lablab

mung

azuki

edamame

peanut

tropkDays after hatch

Nym

phs

per p

lant

Means with the same letter are not significantly different, α = 0.05

2013 PD & MG (June, V)

UNTREATED TREATED

8 September- Midville, GA

31 October- Wayne Co., NC 2012

Kudzu bug activity in soybeans across all planting date/maturity groups

AdultNymph

May June July August Sept.-Oct.

Seasonality 2012

Seasonality 2013

Adult distribution within the canopy

No differences on MG

PD & MG 2012 vs. 2013 – Scotland Co.

Soybean GenotypesVariation 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

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

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

Scout Before You Treat

• Seedling soybeans– “Peel back” foliage and count insects

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

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.

Steward

Intrepid

Dimilin

Belt

Belay

Leverage 360

Baythroid XL, Tombstone Helios

Asana XL

Nufos, Chlorpyrifos

Orthene 97 , Acephate 97

Declare

Cobalt Advanced

Mustang Max

Stallion

Endigo

Sevin, Carbaryl

Karate Z, Warrior

Hero

Brigade, Discipline, Sniper, Fanfare, SkyRaider

Brigadier

Triple Crown

0 20 40 60 80 100

Percent Control (2-5 DAT and 6-14 DAT)P. Roberts, J. All (University of Georgia)J. Greene, N. Sieter (Clemson University)D. Reisig, J. Bacheler (North Carolina State University)16-Jan-13

Kudzu Bug Insecticide Efficacy Summary (2010-2012)

6-14 DAT2-5 DAT

Preserves some

beneficials

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

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