Although there is not yet a large volume
of research regarding the impact of biotechnology on crop yields and returns, the research
that is available supports this expectation.
In a study using 1997 data, the Economic Research Service (ERS) found a statistically
significant relationship between increased crop yields and increased adoption of
herbicide- and pesticide-tolerant crop seeds.5
The ERS study found that crop yields
"significantly increased" when farmers adopted herbicide-tolerant cotton and Bt cotton.6
The use of herbicide-tolerant soybeans resulted in a "small increase" in crop yields.
Another study performed by Iowa State University found that Bt crops out-yielded nonBt
crops. The university studied 377 fields and estimated that crops grown from GM
seeds yielded 160.4 bushels of Bt corn per field, while crops grown from non-GM seeds
yielded 147.7 per field.