Safety of sulfoxaflor and flupyradifurone for aphid predators

J.P. MichaudKansas State University

Sorghum – Sugarcane Aphid Research Exchange Meeting

New Orleans, LAJanuary 7 – 8, 2016

Introduction

• Sulfoxaflor (Dow) and flupyradifurone (Bayer)are both effective against SCA

• How safe are they for predators expected to contribute to biocontrol of SCA?

• We tested Hippodamia convergens with multiple routes of exposure to both(topical, residual, feeding contaminated food)

• We started with recommended field rates (1 oz and 8 oz / acre, application in 10 gal H2O)

• We also reared out survivors to check forsublethal and transgenerational effects

Materials & Methods

• Topical exposure: Known volume of materialapplied to dorsum of adult or 4th instar

• Residue exposure: Application to leaf disc-> 24 h exposure of 1st instar larvae

• Consumption: Aphids sprayed with aphicide,fed to 4th instar larvae

• Mortality tallied after 24 h – survivors matedand reproduction observed

• High mortality – 0.1 X dose tested• Low mortatily – 2.0 X dose tested

Surv

ival

(%, 2

4 h)

Treatment

Topical application to adult H. convergens

Control Sulfoxaflor (1x) Sulfoxaflor (2x) Flupyradifurone (0.1x)

Flupyradifurone (1x)

0

20

40

60

80

100a a

a

b

a

*There were no significant effects on the reproductive performance of survivors

* * * *

Topical application to 4th instar H. convergensSu

rviv

al (%

adu

lts)

Control

Sulfo

xaflor (

1x)

Sulfo

xaflor (

2x)

Flupyradifu

rone (0

.1x)

Flupyradifu

rone (1

x)0

20

40

60

80

100

a

ab

b

c

c

Treatment

H. convergens larvae (1st instar) with 24 hexposure to leaf residues

Control

Sulfo

xaflor (1

x)

Sulfo

xaflor (2

x)

Flupyradifu

rone (

0.1x)

Flupyradifu

rone (1

x)0

20

40

60

80

100

Surv

ival

(% a

dults

)

Treatment

a

b

bcc

H. convergens adults fed contaminated prey (24 h)(surviving adults reproduced normally)

Treatment

Control

Sulfo

xaflor (1

x)

Sulfo

xaflor (

2x)

Flupyradifu

rone (0

.1x)

Flupyradifu

rone (1

x)0

20

40

60

80

100

Surv

ival

(%, 5

day

s)

a

b b

c

d

H. convergens larvae (4th) fed contaminated prey (24 h)(surviving adults reproduced normally)

Control Sulfoxaflor (1x) Sulfoxaflor (2x) Flupyradifurone (0.1x)

Flupyradifurone (1x)

0

20

40

60

80

100

a

b

bc

b

c

Surv

ival

(% a

dults

)

Treatment

Key Learnings• Sulfoxaflor is relatively safe for H.

convergens• Flupyradifurone is moderately

toxic, but probably less so than most conventional alternatives

• Highest risk is for early instar larvae contacting leaf residues• No apparent sublethal effects of either material