Soybean Rust Pustules

Asian soybean rust (ASR) was first detected in the continental U.S. in 2004 in Louisiana. Before the discovery in the U.S., the yield losses caused by ASR in many parts of the world were devastating. In South America, especially in Brazil, yield losses ranged from 10 to 80%. Funding was made available for a network of ASR sentinel plots that would serve as an early-warning system for the presence of the disease. Sentinel plots are planted two to three weeks earlier than commercial fields. If ASR is found in a sentinel plot, this is a signal to scout surrounding fields. The growth difference in sentinel and commercial fields allows growers and farm advisors time to make decisions. If conditions are optimal for the rapid spread of ASR (warm and humid), the solution is treatment with fungicides.

“Soybeans and wheat made an awesome economic combination for growers in the Southeast this year, creating plenty of optimism for profits from this year’s beans and optimism for planting more of the crop in 2013.

Even the earliest appearance on record of Asian Soybean Rust did little to slow down what is shaping up to be one of the best soybean crops on record in some parts of the Upper Southeast.

Rust was detected along a southern tier of North Carolina counties on Sept. 12, but Mother Nature, a well-coordinated system of sentinel plots, and timely actions by growers stopped rust in its tracks.

Though the disease was documented on Sept. 12, in North Carolina, the earliest on record by three days, it appears there will be little damage to the state’s 1.65 million acre soybean crop.

Duplin County, N.C., Extension Agent Curtis Fountain says once the disease was detected in counties less than 100 miles from his county, growers quickly reacted and applied fungicides when needed.

North Carolina State University Plant Pathologist Steve Koenning and Soybean Specialist Jim Dunphy issued timely updates on movement of the disease and provided virtually day-to-day observations on when and what to spray to best manage ASR.”

Author: Roberson, R.
Affiliation: Farm Press, Editorial Staff
Title: Rapid Grower Response, Weather Stop Early Soybean Rust Outbreak
Publication: Southeast Farm Press, December 5, 2012.