Adopter pest control costs can fall, but seed costs rise. A Yield Effect. Adopter yields can increase. A Price Effect. Higher yields and greater production across the Belt lowers prices.
Lower prices affect both adopters and non-adopters.
We developed a 31-region mathematical programming model of U.S. cotton supply and demand. Based on surveys of available studies of bt cotton published in the Proceedings of the Beltwide Cotton Conferences, extension bulletins, and other sources, we developed low, medium, and high estimates of the yield gains from bt adoption for each region. This approach is similar to economic studies of the impacts of pesticide cancellations. Below, we present some preliminary results including cost effects for Arizona. Gross returns measure gains to adopters from higher yields and losses to both adopters and non-adopters from lower prices.