USDA has confirmed that three out of four samples taken from soybean plants during an inspection tour in Louisiana last Thursday were confirmed as testing positive for soybean rust. The confirmed samples came from Iberia, St. John and St. Mary Parishes.

"The sample locations indicate a path that matches the wind patterns of Hurricane Ivan," says Clayton Hollier, an LSU AgCenter plant pathologist and its principal investigator for the Southern Pest Detection Network.

In Mississippi, one instance of soybean rust on a soybean plant has been confirmed in a field located in Adams County.

So far, rust has not been found on kudzu--an invasive ditch-weed that covers about 12 million acres in the southern United States and is the main host plant for the disease.

"Finding Asian soybean rust in this country means farmers will have to make changes in their soybean management practices," says Ken Whitam, LSU AgCenter plant pathologist. "They will have to be diligent in early scouting of the disease and use more fungicides, which will increase their production costs."

Mississippi State University plant pathologist Billy Moore examines the leaves from soybean plants in Adams County last Friday. Today, Nov. 16., the USDA confirmed that the sample tested positive for Asian soybean rust. Three samples taken from soybean fields in Louisiana also tested positive for the disease.

Mississippi State University plant pathologist Billy Moore says later-planted soybeans probably will be at a higher risk of being damaged by the disease than early-planted soybeans.

"We will make a concerted effort to look for rust this spring," Moore says. "If we find rust, we'll recommend a fungicide application at the R1 stage, followed by another application 21 days later."

Moore notes that several new fungicides effective on rust potentially will be on the market at that time.

"We typically get a 5- to 8-bushel yield increase with one application of fungicide in controlling diseases other than rust," he says. "This kind of yield response will help cover some of the application and fungicide costs. The fungicides will help."

"The events in the last week have heightened our sensitivity and awareness on soybean rust in the United States," says Will McCarty, MSU Extension Assistant Director. "We will continue to check fields and other hosts for the presence of rust in Mississippi, and the MSU Extension service will educate growers on possible strategies in the event of occurrence on the 2005 crop."

Farmers are encouraged to attend area meetings this winter to get the right advice on control measures and help in assessing the risk factors associated with their particular operations.