1. Evaluating Insecticide Residual Activity for the Control of Melanaphis sacchari (Zehntner)
Ryan Gilreath
Louisiana State University
Sorghum – Sugarcane Aphid
Research Exchange Meeting
Dallas, TX
January 3 – 4, 2017

2. Introduction Present in Florida since 1977
Present in Louisiana since 1999
2013 found feeding on sorghum
Survived 2013 winter to spread through 13 states in the south
2015 prevalent from the Carolinas to New Mexico
From Texas to Kansas and Illinois

3. Introduction

4. Introduction
Evaluate residual activity of insecticides for controlling SCASCA
Field weathered bioassays conducted in 2015 and 2016 to establish baseline data of residual activity for SCA
Data will be used to benchmark residual activity to enable an insecticidal system of control

5. Materials & Methods Insecticide applied to Boot stage sorghum
Chlorpyrifos (Lorsban 1 qt/ac)
Sulfoxaflor (Transform 1 oz/ac)
Flupyradifurone (Sivanto 4 oz/ac)
Non-treated
Applied with ground operated sprayer
10 GPA
8 leaves sampled
0, 3, 7, 14, 21 DAT
Cut 3-cm diameter leaf discs placed in the cups abaxial side up
Placed a steel washer along with 10 SCA adults over the leaf
Sealed with single ply tissue
Placed in growth chamber at 27 ± 1° C for 48 H.
Used Non-linear regression analyses to model residual activity

6. Lorsban 2015

7. Lorsban 2016

8. Transform 2015

9. Transform 2016

10. Sivanto 2015

11. Sivanto 2016

12. Picture Slides

13. Key Learnings Lorsban and Transform
5 days of activity in 2015
Lorsban outlasted Transform in 2016
Sivanto provided best residual in both years
Three days of rain still gave best residual
Offered about 7-10 days of activity

14. Discussion