USDA Researchers Create Highly Aflatoxin-Resistant Corn

By Hank Becker
March 18, 1999

WASHINGTON, March 18–Agriculture Secretary Dan Glickman announced today a new corn line developed by USDA scientists that outshines all previous corn lines in its ability to naturally fend off aflatoxin, a fungal toxin that poses a threat to humans and livestock. The corn line has been released to seed companies and public research institutions for breeding purposes.

“USDA research provides real world solutions for America’s farmers to ensure their viability and profitability,” said Glickman in remarks to the leadership of the National Corn Growers Association. “Investment in agriculture research is even more critical today so our farmers can maintain their competitive edge in the global marketplace.”

Contamination of corn grain by aflatoxin, made by certain fungi, can be a food and feed safety problem. In 1998, record high temperatures and drought caused aflatoxin levels in corn to soar in parts of the South. Growers' losses have been estimated at $85 to $100 million in Texas, Louisiana and Mississippi.

This new corn line from scientists at USDA’s Agricultural Research Service could be an important step toward the long-term goal of commercial hybrids with strong aflatoxin resistance. Currently, commercial hybrid corn with aflatoxin resistance is not available to farmers.

The new corn line, named Mp715, has lower levels of infection with the fungus and subsequent contamination with aflatoxin. It will take several years before hybrids conventionally bred using Mp715 could be available.

“Corn hybrids that resist both the fungus and its toxin are widely considered the most efficient and reliable way to reduce the accumulation of aflatoxin in corn grain," said ARS geneticist W. Paul Williams who helped create this new corn line.

Williams and his colleagues, plant pathologist Gary L. Windham and geneticist Georgia L. Davis, are working to identify the genes for reduced fungal infection and toxin accumulation in the lines they have now.

Several major commercial seed companies have incorporated into their corn breeding programs the toxin-resistant germplasm released earlier by ARS. To expedite the transfer of resistance to commercial hybrids, ARS recently entered into cooperative research and development agreements with two companies to evaluate hybrids from their breeding programs this summer. ARS scientists will evaluate 75 to 100 hybrids for resistance to aflatoxin accumulation.

Scientific contact: W. Paul Williams, ARS Corn Host Plant Resistance Research Unit, Mississippi State, Miss., phone (601) 325-2735, fax (601) 325-8441, pwilliams@dorman.msstate.edu.