Asian soybean rust has been confirmed for the first time in Mississippi this season. The disease was detected in southeast Mississippi along the Alabama line, according to the USDA's Public Pipe Website.
Soybean rust was detected on July 16 in George County, Miss., on a soybean sentinel plot and three commercial fields, according the USDA.
Following rains for the past week, new reports are expected to continue in the Southern U.S., the USDA says. Soybean rust isn't expected in the central and northern U.S. due to hot, dry weather.
Soybean rust in its early stages. Photo by the University of Delaware Cooperative Extension.
The middle of July was a busy week for the detection of soybean rust in the South. In Florida, two counties reported soybean rust on July 14; in Georgia, one county on July 13; and Alabama, two counties on July 9.
So far in 2012, soybean rust has been reported in 27 counties in the U.S., including six sites in Alabama, eight in Florida, eight in Georgia, two in Louisiana, one in Mississippi, two in Texas, and 13 in Mexico.
Soybean rust was first confirmed in late 2004 on a Louisiana State University research farm.
Soybean rust is a foliar disease found mainly in Asia and Australia until recently. It was found in South America in 2001.
Fungicides have proven very effective in managing the disease.
Lesions first appear as small chlorotic and irregularly shaped spots, burning tan to brown or reddish as the disease progresses The lesions are usually confined to the veins or close to the veins.
Soybean rust causes premature defoliation leading to yield losses, fewer seeds per pod, decreased number of filled pods per plant and early maturity.