Beneficial Insects Affected More by Insecticides than by Bt Crops

Results of a study conducted by researchers at the U.S. Department of Agriculture’s Agricultural Research Service (ARS), University of Nebraska and Iowa State University revealed that non-target insects are more likely to be affected by common insecticides than by crops that express Bt proteins. The scientists compared the effect of the toxins Cry1Ab and Cry3Bb in maize, Cry3A in potato, Cry1Ac and Cry1Ab in cotton and numerous insecticides on a group of non-target insects.

The researchers observed considerable variability in the effects of Bt cotton and maize crops on non-target insects. However, the data within the groups were fairly consistent. The most influential factor was the insecticide applied. Insecticides such as pyrethroids, organophosphates, carbamates and neonicotinoids had larger negative impacts on non-target insects than did the Bt crops. The scientists also observed that insecticides affect insect populations uniformly, regardless of whether they're in Bt or non-Bt crop fields.

 Read the complete article at http://www.ars.usda.gov/is/pr/2008/081124.htm