The United States Department of Agriculture’s (USDA) Integrated Organic Program has awarded Iowa State University (ISU), Michigan State University, University of Florida and the Rodale Institute $480,000 to evaluate strategies for management of soybean rust in organic systems.

The long-term goal of this project is to identify and test best management organic practices for control of Asian soybean rust  (ASR) which is caused by the Phakopsora pachyrhizi fungus. Although ASR, which arrived in the United States in 2004, has not been found in the major soybean production areas this year, it has the potential to be the single most important limitation to organic soybean production in the U.S. The loss estimates of ASR in organic systems range from $30 to $120 million.

 Strategies for soybean rust prevention to be evaluated will include extended crop rotations and windbreaks (to mitigate spore dispersal), USDA National Organic Program (NOP)-compliant fungicides, such as copper sulfate and hydrogen peroxide, and biological controls, such as Bacillus pumilus and other microbial products. This multi-institutional, farmer-based project will include on-station studies and on-farm surveys. Already this year, soybean rust has been discovered in research plots in Florida established in conjunction with the ISU Organic Ag Program.

 “We are hopeful that identification of some effective NOP-compliant fungicides will occur yet this season,” stated Kathleen Delate, ISU agronomist who is working with Ann Blount at the University of Florida in an early trial. “It is important to look at all potential methods of control for the 200,000 acres of organic soybeans in the U.S.,” said Jerry DeWitt, ISU entomologist and co-investigator. 

 In the new four-state project, disease incidence, spread, soybean yields and seed quality will be monitored. Evaluation of this effort, including economic analysis of the cost of production of soybean rust management techniques, will be conducted with farmer-cooperators. This project will create a strong national network for ASR monitoring and provide best management practices for controlling ASR in organic systems. Information on organic production and soybean rust can be found at http://extension.agron.iastate.edu/organicag/.