1. Scott D. Stewart (project leader)
Summary of Standardized Efficacy Trial for Sugarcane Aphids in Grain Sorghum
Scott D. Stewart
(project leader)

2. Co-Authors (data providers)
David Buntin (University of Georgia)
Francis Reay-Jones (Clemson University)
Gus Lorenz (University of Arkansas)
Scott Stewart (University of Tennessee)
Ali Zarrabi (Oklahoma State University)

3. A Reminder From Last Year’s Meeting Average Number of SCA (middle + flag leaf)AB B C A B
9 Trials Trials Trials

4. Another Reminder From 2015 Rate Response of Transform and Sivanto
(8 oz in one test)

5. Objectives
To evaluate residual control of SCA provided by reduced rates of Transform and Sivanto by themselves and in combination with each other
Determine how tank-mix partners potentially used for other pests might influence the control of SCA
Food for Thought – Should we use reduced-rate mixtures of Transform and Sivanto as a method of resistance management?

6. The Protocol TREATMENTS METHODS Untreated Transform 1.5 oz
Sivanto 5 oz
Sivanto 2.5 oz
Transform 0.75 oz + Sivanto 2.5 oz
Transform 0.75 oz + Lorsban 16 oz
Sivanto 2.5 oz + Lorsban 16 oz
+ Suggested optional treatments
Small plot
RCBD
4 Replicates
No adjuvants
Count aphids at 3-5, 7-10 and DAT
Count at least 10 total leaves per plot
Collect yield where possible

7. Yield (B/A) of Standardized Efficacy Trials (2016)
Treatment
(Oz/Acre) GA SC AR
TN-1
TN-2 OK
Average
Untreated -
42.6 a
39.3 b
38.1 c
8.8 c
45.6 b
34.9 C
Transform (1.5)
49.1 a
41.3 b
79.6 ab
38.3 b
80.9 a
58.2 BC
Transform (0.75)
48.5 a
44.8 ab
64.2 b
29.4 b
75.9 a
52.4 C
Sivanto (5.0)
52.9 a
57.5 a
75.5 ab
82.8 a
83.7 a
70.9 AB
Sivanto (2.5)
67.7 a
57.0 a
83.1 a
73.8 a
76.3 a
72.1 AB
Transform (0.75) + Sivanto (2.5)
79.7 a
49.3 ab
87.7 a
85.8 a
85.7 a
77.4 A
P =
Significant effect of location on treatment response (P = )

8. Lorenz (University of Arkansas)

9. Stewart – 1 (University of Tennessee) Early planted (application at early-heading)

10. Stewart – 2 (University of Tennessee) Late planted (application pre-heading)
Lorsban (16 oz), Dimethoate 4EC (16 oz), Pyreth (Mustang Max, 3.2 oz)

11. Buntin (University of Georgia)
Lorsban (16 oz), Pyreth (Karate Z, 1.92 oz)

12. Zarrabi (Oklahoma State University)

13. F. Reay-Jones (Clemson)
Lorsban (16 oz), Pyreth (Bifenthrin 2E, 5 oz)

14. F. Reay-Jones (Clemson)
Lorsban (16 oz), Pyreth (Bifenthrin 2E, 5 oz)

15. Conclusions
Sivanto provided better control and protection than Transform
The 2.5 oz rate of Sivanto generally provided similar aphid control and plant protection as did the 5 oz rate
Low rates of Sivanto sometimes worked less quickly (especially in the lower canopy)
Mixing reduced rates of Sivanto and Transform was a good treatment but did not substantially improve control
Adding other components, if anything, tended to hurt performance of Transform or Sivanto
I’ll ask the question again …
Should we use reduced-rate mixtures of Transform and Sivanto?