Crop Biotech Update

Lab Tests Can Accurately Identify Potential Risks of Bt Crops in the Field

November 13, 2009

Results of a study conducted by scientists at the US Department of Agriculture-Agricultural Research Service (USDA-ARS) showed that potential risks from genetically modified, insect resistant (Bt) crop lines can be assessed using carefully controlled laboratory tests,  therefore reducing the need for time consuming and costly tests. In collaboration with researchers at the Santa Clara University, the ARS scientists compare all current laboratory and field studies on non-target effects using meta-analyses.

For Cry proteins targeting Lepidopteran pests, the scientists found that laboratory studies correctly predicted the reduced field abundance of non-target Lepidoptera. For predators on the other hand, the ARS researchers found that laboratory studies predicted reduced abundances that were not realized in field studies and "thus overestimated ecological risk."

"Our findings support the assumption that laboratory studies of transgenic insecticidal crops show effects that are either consistent with, or more conservative than, those found in field studies, with the important caveat that laboratory studies should explore all ecologically relevant routes of exposure," wrote the researchers in the current issue of the journal Biology Letters.

The open access paper is available at http://dx.doi.org/10.1098/rsbl.2009.0612 For more information, read http://www.ars.usda.gov/is/pr/2009/091112.htm