Two new cases of Asian soybean rust were confirmed June 29 in sentinel plots in Baldwin County, Alabama and Marion County, Florida. The announcement was made by USDA Thursday morning, June 30.
While soybean rust was identified on kudzu plants in six Florida counties earlier this year, this is the first incidence of rust on soybean plants in Florida for 2005. It is also the first incidence of rust in Alabama. The only other report of soybean rust has been in Seminole County, Georgia on volunteer soybeans in late April.
Ed Sikora, Extension plant pathologist with Auburn, reports that rust spores in Alabama were found on Tuesday afternoon (June 28) in sentinel plots around Fair Hope, which is in the extreme southwest part of the state across the bay from Mobile. According to USDA reports no rust was found June 29 in sentinel plots in Calhoun, Etowah, Talladega or DeKalb counties in east central Alabama or Fayette county in west central Alabama.
The new case of rust was found on two plants with "roughly 10 leaves on each plant showing symptoms in the lower canopy -- typical lesion formations," Sikora said. The samples were brought to Auburn and rust was then confirmed through several tests.
According to Sikora, two sentinel plots were planted in the area -- one late; one earlier. One of the infected plants was found in the older sentinel plot where beans were at R-6. The other plant was found on the neighboring sentinel plot at R-1/R-2.
"We also have Syngenta spore traps -- slides covered with petroleum jelly -- in the area," said Sikora. "On Monday, we found four spores that look like Asian rust spores in one of those traps."