Genetically Engineered Corn May Have Adverse Effects on Monarch Butterflies

Genetically engineered corn that produces the insecticidal protein called Bt may have an adverse effect on monarch butterfly larvae if the corn is widely planted, researchers from Cornell University report in today’s Nature. Although the larvae feed only on milkweed, pollen from the corn can disperse as far as 180 feet from the cornstalks, landing on milkweed. Entomologist John E. Losey and his colleagues found that larvae raised on milkweed leaves dusted with pollen from Bt corn ate less, grew more slowly and suffered higher mortality than larvae exposed to pollen from normal corn.

Compiled by Times medical writer Thomas H. Maugh II