March 16, 2004

Source: Iowa Farm Bureau

Iowa State University is the lead institution on a $900,000 federal grant to develop new ways to prevent the spread of diseases carried by seeds.

The four-year project, funded by the U.S. Department of Agriculture, will develop new techniques to detect seedborne pathogens, as well as train diagnosticians in using new methods.

"Our country has done a good job in keeping pathogens out of the system. But after Sept. 11, our commitment to tighter security revealed that seedborne diseases could be a potential weak link," said Manjit Misra, director of the Seed Science Center and the Biosafety Institute for Genetically Modified Agricultural Products.

"In collaboration with our research partners at the university of Georgia and Clemson University, we hope this project will strengthen the protection of American agriculture and the food supply," said Misra. "These funds come from a highly competitive USDA grant program, another indication that Iowa State is a recognized leader in food safety and biosecurity."

Detecting pathogens in seed can be "like looking for a needle in a haystack," Misra said. "If that is the case, this research aims to develop tools that, in effect, make pathogens as visible as pitchforks."

One technique, called magnetic capture hybridization, will use magnetic beads that bind to the targeted pathogen’s DNA, allowing them to be separated from other DNA. Once a pathogen’s DNA is isolated, it may be enlarged and studied when seed samples are subjected to a process called polymerase chain reaction. The method is rapid, highly sensitive and specific.

As the administrative unit of the USDA’s National Seed Health System, the Seed Science Center helps develop standardized seed tests. The new project will build on the work of this system, said Denis McGee, a professor of plant pathology who oversees the system.

"Seeds are an internationally traded commodity," McGee said. "They can carry diseases around the world if they aren’t closely monitored."