what is the baseline susceptibility of aphids to transform and sivanto prime?

What is the Baseline Susceptibility of Aphids to Transform and Sivanto?

David Kerns, Sebe Brown & John David GonzalesLouisiana State University AgCenter

Sorghum – Sugarcane Aphid Research Exchange Meeting

New Orleans, LAJanuary 7 – 8, 2016

CollaboratorsName Affiliation Trial Location 2014 2015Gus Lorenz University of Arkansas Rowley & Marianna, AR July Aug

Michael Brewer Texas A&M University Corpus Christi, TX July June

Kathy Flanders Auburn University Clanton & Macon Co., AL Aug June

Amanda Jacobson Auburn University Brewton, AL -- July

Tom Royer Oklahoma State University Lane & Garfield Co., OK Aug Aug

Stephen Biles Texas A&M University Port Lavaca, TX Aug --

Scott Stewart University of Tennessee Madison Co., TN -- Aug

Danielle Sekula Texas A&M University Weslaco, TX Aug June

Angus Catchot Mississippi State University Starkville & Grenada, MS Aug July

Nick Seiter University of Arkansas McGehee, AR -- Aug

David Buntin University of Georgia Pike Co., GA -- Oct

Drew Higgins Higgins Farms Castro Co., TX -- Aug

Francis Reay-Jones Clemson University Florence, SC -- July

Shelby Williams Ag-Venture Seed Poinsett Co., AR -- July

Kerns, Brown & Gonzales

Louisiana State University Alexandria, Jonesville, Winnsboro, St Landry &

Somerset, LA

July, July, Aug

Jun, Jun, Aug

Introduction

• Research will establish early baseline data on key insecticides used to manage sugarcane aphid.

• Baseline data will be used to benchmark insecticide efficacy so shifts in susceptibility can be later detected in subsequent years.

Materials & Methods• Bioassays with Transform in 2014 & 2015, and Sivanto

in 2015.• Utilized a leaf dip method.

– Insecticide concentrations tested included: 0.0, 0.5, 2, 5, 10, 15, 25, and 35 ppm active ingredient.

– Included Induce non-ionic surfactant at 0.5% v/v.• 8 replicates per dose

• Prepared 29-ml condiment cups with 2 ml of agar.• Cut 3-cm diameter leaf discs placed in the cups abaxial

side up.• Placed a steel washer over the leaf.• Placed 10 adult SCA on the exposed leaf in each cup.• Sealed with single ply tissue.• Placed in growth chamber at 27 ± 1° C for 48 H.

Procedures

Sulfoxaflor 2014

Alexandria, LA

Port Lavaca, TX

Weslaco, TX

Jonesville, LA

Starkville, MS

Corpus Christi, TX

Lane, OK

Clanton, AL

Rowley, AR

Winnsboro, LA

mean median

0

2

4

6

8

10

12

14

16

Sulfoxaflor (LC50

-ug/ml)

Sulfoxaflor 2015

Castro County, TX

Garfield County, OK

Florence, SC

Grenada, MS

Pike County, GA

Poinsett County, AR

Madison County, TN

Marianna, AR

Somerset, LA

Corpus Christi, TX

Macon County, AL

St. Landry Parish, LA

Brewton, AL

Weslaco, TX

Winnsboro, LA

Mean Median

0

2

4

6

8

10

12

14

16

Sulfoxaflor (LC50

-ug/ml)

Flupyradifurone 2015

Castro County, TX

Florence, SC

Weslaco, TX

Grenada, MS

Pike County, GA

Brewton, ALCorpus Christi, TX

Macon County, AL

St. Landry Parish, LA

Madison County, TN

Garfield County, OK

Marianna, AR

McGehee, ARPoinsett County, AR

Somerset, LA

Winnsboro, LA

Mean Median

0

2

4

6

8

10

12

14

16

Flupyradifurone (LC50

-ug/ml)

Variability

LC50

(ug/ml Leaf D

ip)

0

2

4

6

8

10

12

14

16

18

Sulfoxaflor 2014 Sulfoxaflor 2015 Flupyradifurone 2015

Correlating Susceptibility 2015

Key Findings• Developed baseline susceptibility

data for sulfoxaflor and flupyradifurone.

• Sulfoxaflor slightly more toxic to SCA than flupyradifurone.

• Toxicity of sulfoxaflor and flupyradifurone were not correlated.

• Sulfoxaflor susceptibility slightly decreased in 2015 relative to 2014.

Next Steps• Need to determine if shipping aphid

samples affects bioassay results.• Continue monitoring.

Discussion