Planting soybeans early this spring will not produce better yields and could cause disease problems later this summer, says Greg Shaner, Purdue University plant pathologist.
"Soybeans planted early are at greater risk of Sudden Death Syndrome (SDS) than soybeans planted later," says Shaner. "The majority of severe Sudden Death Syndrome samples submitted to Purdue by soybean growers have come from early planted fields."
Other factors for the disease are susceptibility of the soybean variety, weather and how often soybeans are grown in a field, he adds.
Purdue research has shown there is no yield advantage to early planting, which stresses the plants and increases the risk for disease problems.
Planting last year’s soybean fields in corn won’t keep farmers safe from SDS. "There is no way to avoid the threat of SDS," Shaner says.
"The fungus survives in soil and can persist for several years even though soybeans are not grown. The key to reducing loss from this disease is through managing it, not avoiding it."
Shaner recommends planting soybeans May 5-20 in fields with a history of SDS. He also suggests planting resistant varieties. "There are few varieties with complete resistance to SDS. However, the resistant varieties are damaged less and yield better than susceptible varieties when the disease strikes," he says.