1. Influence of Adjuvants on Leafspot Disease Management
March 6, 2019
Dr. Corey Guza
Michigan Sugar Company

2. Introduction
Leafspot management (Cercospora and Alternaria) continues to be a challenge for Michigan Sugar Company growers.
Growers are spraying 8 to 10 times to manage disease.
Can adjuvants improve fungicide efficacy?
Can improved efficacy result in increased sugarbeet yield (RWSA)?

3. Diligence Wilbur Ellis
Adjuvants
Deposition Aid-Canopy Penetration-Coverage-Spreader-Sticker & Drift Control Agent
Masterlock WinField United
Extender and Sticker
Reguard Wilbur Ellis
Deposition Aid-Drift Control Agent
Diligence Wilbur Ellis

4. Materials and Methods Fungicide Rate Timing Super Tin 8 fl oz/A 14 day
EBDC
2 lb/A
10 day
Copper
2 pt/A
7 day
EBDC*
7-14 day
Adjuvant
Rate
Masterlock
6.4 oz/A
Reguard
12 oz/A
None
Reguard + Diligence*
12 oz/A +
2 oz/A
*2018
*2018

5. Materials and Methods Plot size: 6 rows (22 inch) x 38 ft
6 replications
Monosem research planter 4.1 inch seed spacing
Final population of 200 beets/100 ft
Compressed air small plot sprayer
3 mph
25 gallons per acre
100 psi
Flat Fan nozzles
Data Analyzed w/ARM Fishers LSD 5%

6. Materials and Methods Evaluations, 3 years, 2016-2018:
Percent leaf damage from leafspot late Sept - early Oct
Root Yield (RWSA)

7. Results – Super Tin C B A
2016

8. Results – Super Tin A A A
2017

9. Results – Super Tin B A A A
2018

10. Results - Copper B A A
2016

11. Results - Copper B A A
2017

12. Results - Copper A A A A
2018

13. Results – EBDC 10 Day Interval
2016

14. Results – EBDC 10 Day Interval
2017

15. Results – EBDC 10 Day IntervalAB A A
2018

16. Results - EBDC(7 Day Interval)AB A A A
2018

17. Results – EBDC 10 Day IntervalAB A A
2018

18. Results - EBDC(14 Day Interval)AB A A A
2018

19. Results – EBDC 10 Day Interval
2016

20. Results – EBDC 10 Day Interval
2017

21. Results – EBDC 10 Day IntervalAB B B
2018

22. Results - Summary Super Tin Copper EBDC Triazole
All adjuvants increased control
Some may cause injury
Copper
Influenced the least by the addition of any adjuvant
Some times can reduce control
Risk of crop injury
EBDC
Shorter application intervals equals better control
No Sticker at 7 days is better than any treatment at 10 days
Triazole
Generally tankmixed with EBDC
Choose an adjuvant that is effective with EBDC
Some triazoles require additional surfactant

23. Remarks Adjuvants generally improve leafspot control
Hot humid weather conditions can cause leaf injury
Adjuvants are not “extenders”
When used appropriately adjuvants can improve disease control from using fungicides and as a result increase sugarbeet yield.

24. Thank You!
Dr. Corey Guza
Michigan Sugar Company