Magazine article Science News

Rethinking Refuges? Drifting Pollen May Bring Earlier Pest Resistance to Bioengineered Crops

Magazine article Science News

Rethinking Refuges? Drifting Pollen May Bring Earlier Pest Resistance to Bioengineered Crops

Article excerpt

Pollen wafting from bioengineered corn to traditional varieties may be undermining the fight to keep pests from evolving resistance to pesticides, according to a new study.

Farmers who plant Bt corn, which is genetically engineered to make an insecticide produced by the bacterium Bacillus thuringiensis, by law must plant non-Bt corn nearby, explains Bruce Tabashnik of the University of Arizona in Tucson. By harboring susceptible pests, those non-Bt rows of corn, called a refuge, are supposed to slow down a pest population's tendency to develop resistance to the Bt pesticide.

Tests show, however, that pollen from the Bt corn drifts over into the refuge and creates Bt-laced kernels in the ears of otherwise non-Bt plants, say Tabashnik and Charles Chilcutt of Texas A&M University in Corpus Christi. The rules for refuges may need revising, the researchers say in an upcoming Proceedings of the National Academy of Sciences.

The impact of the finding comes from the context, Tabashnik says. Botanists probably could have predicted the results, but he says refuge designers, including himself, hadn't factored in the migration of engineered genes. "It's not in any of the models I've ever seen, and I've been doing this for 20 years," says Tabashnik.

Another specialist in insect resistance, David Onstad of the University of Illinois at Urbana-Champaign, calls the new report "an important paper with practical consequences."

Tabashnik says that farmers might have to plant wider refuges or use varieties of corn in the refuges that bloom at slightly different times than do the nearby Bt varieties. …

Search by... Author
Show... All Results Primary Sources Peer-reviewed

Oops!

An unknown error has occurred. Please click the button below to reload the page. If the problem persists, please try again in a little while.