a full report in Agricultural Research.
By Linda McGraw
August 3, 2000
An egg white protein called avidin can
give corn insect resistance that lasts from the field to the storage bin.
Unlike chemical insecticides that can be washed off by rain or inactivated by
ultraviolet rays, avidin works regardless of the weather.
Agricultural Research Service chemist
Karl J. Kramer and colleagues at the Grain
Marketing and Production Research Center in Manhattan, Kan., were the first
researchers to report avidins lethal effect on stored-product beetles and
moths. Each year, insects damage stored commodities--corn, wheat, rice, and
grain sorghum-- causing multimillion-dollar losses. In 1994, the U.S.
Department of Agriculture began a national integrated pest management
initiative. ARS researchers have been developing nonchemical alternatives for
controlling insect pests, weeds, and crop diseases.
Avidin sequesters biotin, a vitamin essential for insect growth. Feeding
insects avidin produces a vitamin deficiency that leads to stunted growth and
death. These studies come out of a partnership between ARS and
ProdiGene, in College Station, Texas.
ProdiGene produces transgenic corn with avidin. ARS researchers monitor how
much avidin is needed to effectively kill insect pests. Cornmeal made from
avidin corn resisted insect pests, demonstrating that products made from avidin
corn will have a longer shelf life. That means corn farmers can sell higher
quality corn that can be stored longer without pesticides.
Although avidin is already a common protein in human diets, the
Food and Drug Administration will require a
thorough risk assessment of avidin corn before approving it for food or feed.
For a full report, see the August issue of Agricultural Research magazine.
ARS is the chief research agency for the U.S.
Department of Agriculture.
Scientific contact: Karl J. Kramer, ARS Grain Marketing and
Production Research Center, Manhattan, Kan., phone (785) 776-2711,