Bob Mulrooney, Extension Plant Pathologist; bobmul@udel.edu
Septoria brown spot has been favored by all this wet weather and is easily found on the unifoliate leaves and the lower trifoliate leaves in most areas. These will usually fall from the plant and if it dries out we will not see this disease again until the soybeans canopy and conditions again would be favorable for infection. Most seasons this disease is not yield limiting. Spots seen this week were small but very numerous in one variety trial that I checked. 
Septoria brown spot on unifoliate leaves of soybean
Soybean Rust Update
Soybean rust was reported in Geneva, Covington and Conecuh counties in south-central Alabama on kudzu on June 24. The disease was found at very low levels at each site which included two seperate kudzu patches in Covington County. On June 22, soybean rust was reported in a soybean sentinel plot in Acadia Parish in Louisiana. Soybean rust scouting continues in the U.S. and Mexico. The current conditions in the South are not going to be very favorable for rust development due to high temperatures.
