An Iowa State University plant pathologist has been recognized for his role in helping the U.S. soybean industry better manage the risk of soybean rust.

X.B. Yang is a leading expert on soybean rust and has studied the disease since 1989. He is a member of the U.S. Department of Agriculture Asian Soybean Rust Team. Team members were presented a 2006 USDA Secretary's Honor Award during a ceremony today in Washington, D.C.

The annual awards are considered the most prestigious given by the USDA, and recognize USDA employees and private citizens who have made outstanding contributions supporting the department's mission.

Yang was joined by USDA scientists and researchers from six other universities in accepting the award in the "Enhancing Protection and Safety of the Nation's Agriculture and Food Supply" category. U.S. Secretary of Agriculture Mike Johanns presented the award.

Asian soybean rust is an aggressive fungal disease that can reduce soybean yield substantially. It was first recorded in Japan in 1902. The pathogen moved throughout Asia, Australia and Africa before it was discovered in South America in 2000. It is believed to have arrived in the United States via Hurricane Ivan in 2004, and was first reported in November of that year in Louisiana.

This year, it has been found in many states, including Illinois and Missouri. The disease has not yet been detected in Iowa.

Yang uses weather models and maps to track wind movements that could carry rust spores. "Soybean rust will not overwinter in Iowa," Yang said. "Its outbreaks are associated with the amount of precipitation in a growing season. The disease needs lots of rain to cause damage."

Yang also serves on the Iowa Soybean Rust Team that was formed in 2002 to help Iowa producers prepare for Asian soybean rust. Team members include personnel from Iowa State University, the Iowa Soybean Association, the Iowa Department of Agriculture and Land Stewardship and the USDA Animal and Plant Health Inspection Service.