"It's not a question of if this disease will enter the United States, but when," explained United Soybean Board Production Chair Bryan Hieser, a soybean farmer from Minier, IL.
Hieser said soybean rust is a fungus that spreads by airborne spores and originated in Asia and Australia. In 2001, the disease was identified in the Western Hemisphere, in Brazil and Paraguay. Last year, the disease was identified further north in the Motto Grosso region of Brazil.
"Through our checkoff, U.S. soybean farmers are taking a proactive approach to fighting this disease," said Hieser. "USB first approved soybean checkoff funding for rust research more than a year ago, in December 2001."
The checkoff-funded research includes screening of existing varieties and exotic germplasm to find sources of rust resistance, identifying management recommendations for controlling the disease when it enters the United States and the use of weather models to help predict the spread of rust.
"We have already screened close to 3,600 lines for rust resistance in a two-stage process. Of those, 79 lines appear to have some tolerance to the disease," said Reid Frederick, Ph.D., coordinator of the checkoff-funded rust research under way at the U.S. Department of Agriculture's Agricultural Research Service (USDA-ARS) Foreign Disease-Weed Science Research Unit (FDWSRU) in Ft. Detrick, Md. The varieties are screened for resistance in the special Biosafety Level 3 containment facilities at the FDWSRU in Ft. Detrick.
"We have also planted U.S. varieties in rust-infected counties and are collaborating with scientists in those countries who are conducting tests for the disease," said Frederick. "In addition to soybean checkoff funds, we have also received more than $1 million in funds from ARS to sequence the two rust pathogens. And the Department of Energy is matching those funds."
Hieser mentioned that in May of 2002, the soybean checkoff was responsible for organizing a critical meeting that brought together soybean rust researchers, like Dr. Frederick, with representatives from the USDA's Animal and Plant Health Inspection Service, the Cooperative State Research, Education and Extension Service, and the American Soybean Association to decide on the role each of these organizations would take to prepare the United States for soybean rust.
"Shortly after that meeting, USB and the soybean checkoff developed diagnostic guides for soybean rust that were distributed to farmers, crop consultants, county and university extension agents, plant pathologists and others," said Hieser.
The soybean checkoff rust diagnostic guide is available online at www.unitedsoybean.org. Rust information is also available in the printed and online versions of the U.S. Soybean Diagnostic Guide, also developed by the soybean checkoff. The U.S. Soybean Diagnostic Guide provides diagnostic information on more than 100 soybean production problems, diseases and abnormalities in addition to rust. This guide is also available at www.unitedsoybean.org.
Farmers who think they see symptoms of soybean rust in their fields are encouraged to contact their local county extension agent or university plant disease diagnostic center immediately. A listing of diagnostic centers may be found in the "directories and rosters" section of The American Phytopathological Society Web site at www.apsnet.org.