Soybean Disease Update – June 24, 2011

Soybean Rust Report
There is very little soybean rust activity to report. It has been very dry and hot in the Gulf Coast region where soybean rust overwinters. It has only been found on kudzu so far this season. The risk of soybean rust is very low now even for the southeast. I continue to monitor soybean rust development in the south and will provide a report periodically as the season progresses.

soybean rust map

 

Septoria Brown Spot
Septoria brown spot is one of the earliest fungal diseases that we see on soybean and can be found on the unifoliate leaves and the lower trifoliate leaves when it is present. Badly infected unifoliate leaves will usually fall from the plant and we will not see this disease again until the soybeans canopy and conditions would be favorable for infection. Most seasons this disease is not yield limiting.

Septoria brown spot on unifoliate leaves of soybean.

 

Septoria brown spot on unifoliate leaves of soybean.