The highly contagious soyabean rust disease was confirmed in South Carolina, making it the fifth state this year to find the fungus, the US Agriculture Department said on its rust-monitoring Web site.
The disease was discovered in a commercial soyabean field in Hampton County, which is in the far southern part of South Carolina.
Suspicious spores were also found in a commercial soyabean field in South Carolina's Dorchester County. John Mueller, a plant pathologist with Clemson University, said that sample "strongly resembled the pustules" from Hampton County but it was not possible to confirm the spores as soyabean rust.