April 21, 2000

Finding new ways to reduce aflatoxin in crops is the focus of a Texas Agricultural Experiment Station study that researchers hope will lead to reducing the economic hardship the fungus places on the state’s corn farmers.

"It can lead to incredible financial losses," says Dr. Nancy Keller, an Experiment Station mycotoxin researcher. "Every two to three years, an epidemic can cost $30 million to $200 million (in crop losses)."

Keller’s research is aimed at reducing aflatoxin production using nontraditional methods.

"What I decided to do was find the genes in Aspergillus (a fungus that thrives on oilseed crops) that produce aflatoxin," Keller said. "If you can clone these genes, then you can ask what turns the genes on and off. That’s a powerful thing. So we’ve cloned the genes in the fungus that make aflatoxin.

"Now we can perform experiments and see what makes the genes turn on and off—with the thought that those factors that turn on the genes should be eliminated."

Keller said there are a couple of factors controlling aflatoxin production, including a genetic pathway in the fungus itself that controls the aflatoxin genes. She said research also focuses on the factors involving the host seed that play a role in the interaction with Aspergillus.

"We are also looking to see if there are any components of the seed that may be turning on the aflatoxin genes or if there are any environmental factors such as pH that turn on the genes," she said.