Resistance Management and Sustainable Use of Agricultural Biotechnology

1. Resistance Management and Sustainable Use of Agricultural Biotechnology George Frisvold Department of Agricultural & Resource Economics University of Arizona 4th Annual Berkeley Bioeconomy Conference in conjunction with the NC-1034 Research Conference University of California, Berkeley March 24-6, 2011

2. Problem Statement • Transgenic crop varieties with insect resistant (IR) and herbicide resistant (HR) traits can provide significant economic and environmental benefits • Benefits will be short-lived if resistance not delayed

3. Problem Statement • Despite 3 documented cases of field-evolved resistance, there have been no economically significant field control problems for IR Bt crops • Glyphosate-resistant weeds have become an economically significant problem in the SE US • What accounts for the difference?

4. What’s at Stake? • Loss of economic benefits • Loss of environmental benefits • Negative demonstration effect for biotechnology

5. Adoption of genetically modified (GM) crop varieties (as a share of world hectares and as a share of hectares in approving countries)

6. Difference in Resistance • Depends on attributes of Bt and HR crop technologies • Consistency with IPM principles • Diversification vs. concentration in pest control • And on regulatory and institutional setting • This also depends on attributes of technology

7. Properties of IR and HR Crops

8. Properties of IR and HR Crops

9. Organization of Resistance Management • Miranowski & Carlson, National Academy book chapter (1986) • Predicts organizational form of RM • Useful starting point • One would expect voluntary, monopolist led RM for HR crops • Expect more regulatory approach for IR crops

10. 3 Documented cases of field-evolved resistance to Bt crops • Spodoptera frugiperda (fall armyworm) to Cry1F toxin in Bt corn in Puerto Rico • Busseola fusca (maize stalk borer) to Cry1Ab in Bt corn in South Africa • Helicoverpa zea (cotton bollworm) to Cry1Ac and Cry2Ab in Bt cotton in the U.S. Southeast • Possible 4th case: (pink bollworm) in India

11. Bt crop resistance & susceptibility • 5 studies from China and India with ambiguous evidence of resistance of Helicoverpaarmigera to Cry1Ac in Bt cotton. • No increase in resistance for 7 pests • H. zea and H. armigerastill susceptible across many areas

12. Resistance has not led to field level control failures • Chemical control of target pests still effective • Introduction of crops with multiple Bt toxins • But . . . 2010 saw increase in bollworm / budworm spraying and damages in MS Delta

13. Acres treated trending up in LA & MS

14. Applications up in all 3 states

15. Greater losses per acre in 2010

16. Weed species with glyphosate resistantpopulations states with glyphosate-resistant weed populations Populations,blue States,red

17. Costs of HR weeds • Weed management cost estimates in US range from $30-$160 per hectare • Severe cases have led to crop abandonment • Regarding Palmer amaranth “there are no economical programs to manage this pest in cotton (Culpepper and Kichler, 2009)”

18. Rise in Glyphosate, Loss of Diversity of Mode of Action

19. Corn Reliant on Glyphosate and Triazine Herbicides

20. Price Indices for Agricultural Inputs in the US

21. Herbicide Prices Have Fallen Relative to Other Inputs

22. Special Issue: Herbicide Resistant Crops: Diffusion, Benefits, Pricing, and Resistance Management Volume 12 // Number 3 & 4 // 2009

23. Percent of growers often or always adopting resistance management practice US Cotton Source: Frisvold, Hurley, and Mitchell, 2009

24. Corn Percent of growers often or always adopting resistance management practice Cotton Soybeans

25. Plant Breeders to the Rescue? • Pyramiding multiple Bt toxins in single crop varieties • Stacking traits – Crops that are resistant to multiple herbicides • Allows rotating herbicides with different modes of action • Homogeneous blends – mixtures with different modes of action • Quick registration of blends anticipated

26. Top-Down vs. Bottom Up Approaches to RM • Top-Down • Less management intensive • Relies on a small number of traits (are these enough given resistance to individual traits?) • Growers passively selecting products off the shelf • Relies on technology to keep one step ahead of resistance • Treadmill continues in different form?

27. Top-Down vs. Bottom Up Approaches to RM • Bottom Up • Active grower involvement in cooperative RM • Education to combat common pool externalities • Two way flow of information between growers and scientists / regulators

28. Lessons from Arizona • Bt cotton introduced into mature area-wide IPM program • Heavy reliance on scientific information • Insecticide use on target pest (PBW) and for all pests has declined • No increase in resistance • PBW Eradication under way with Bt cotton as a centerpiece

29. Total AZ Cotton Insecticide Applications Trending Down Source: Frisvold, 2009

30. Trend Continues 30

32. Summing Up • Failure to develop successful RM strategies will deprive current adopters of the benefit of crop biotechnology & have a negative demonstration effect • Key factors determining RM success are technology attributes and institutional capacity • Public and private plant breeding can play a critical role in developing stacked traits that reduce over-reliance on single chemical compounds • IR and HR crops will be more sustainably deployed if embedded in IPM / IWM programs with strong, outward extension linkages to farmers and backward linkages to research institutions • Role of Extension • Information provision • Can facilitate farmer collective action for area-wide RM • Provide government agencies with information needed to increase the flexibility and cost-effectiveness of resistance management regulations