• Early movement of the pathogen from these over-wintering sites and continued wet weather would suggest that rust will be a greater threat to soybean farmers in Alabama in 2013.
Soybean rust-infected kudzu was found in a protected site in downtown Selma in Dallas County, Ala., on April 4, according to Ed Sikora, Auburn University Extension plant pathologist.
Dallas is the fifth county where soybean rust (SBR) has been found over-wintering in Alabama this year, he says.
Low levels of SBR-infected kudzu continue to survive in Montgomery County as well, he adds.
Significant amounts of the disease were observed in both Mobile and Baldwin counties in recent weeks and the disease was observed in Dothan in February.
“This is the highest amount of SBR inoculum I have observed surviving on kudzu in Alabama at this point in the spring in nine years of monitoring for the disease,” says Sikora.
“The ‘find’ in Selma is the farthest north SBR has ever been detected over-wintering successfully in the United States. It appears warm winter temperatures have allowed SBR to survive the winter on kudzu along the Gulf Coast and in a few urban-areas further inland.”
The disease has now been found in eight parishes in Louisiana, five counties in Alabama, four counties in Georgia, and three counties in Florida. All of the reports have been on kudzu with the exception of one case of SBR detected on volunteer soybeans in Louisiana.
In Mexico, SBR has also been reported on soybeans, jicama and yam bean in January of 2013.
“We will continue to monitor for the disease on kudzu for the next few months to see if the disease begins to spread earlier than in past growing seasons. We are starting to plant our soybean sentinel plots around the state as weather permits.
“Early movement of the pathogen from these over-wintering sites and continued wet weather would suggest that SBR will be a greater threat to soybean farmers in Alabama in 2013. However we are still at the ‘wait-and-see’ stage with the disease this year,” says Sikora.
Sikora will start the soybean rust hotline in mid-May and possibly earlier with the disease being so active this winter. He can be contacted at 334-332-7433.