Soybean Rust Update

Bob Mulrooney, Extension Plant Pathologist; bobmul@udel.edu

On September 11th, soybean rust was reported on soybean plants from George and Yazoo Counties, Mississippi. On September 10th, soybean rust was reported on soybean plants from Colquitt County, Georgia and on kudzu in Okaloosa County, Florida. That makes 23 new county reports since September 1st.

As you can see soybean rust is picking up some steam, in the Gulf States primarily, but has spread to southeast AK as well. It is not moving up the Atlantic Coast at this time. Fortunately for us Hurricane Hanna could have been a transport event bringing spores from the FL and GA but its track moved more easterly taking any possible spores out to sea. Had the storm hit a few days later and moved a little more to the west we could have had some movement of spores into Delmarva. It is too early to predict if there will be any effects from Hurricane Ike, but the forecast is as follows:

The path of Hurricane Ike will have a very strong bearing on what areas will observe an increased risk of spore transport and deposition over the weekend. The cold front combined with Ike will transport spores as far northeastward as New Jersey. Deposition and survival will be possible in areas of heavy cloud cover and rain, such as Texas, the Lower Mississippi River Valley, and the southern Great Plain states. Spraying is not recommended.

It still looks like we will miss soybean rust this year but with as many late soybeans as there are this year there is always a chance, even if it is low. You can keep current on the situation by visiting the ipmPIPE website at http://sbr.ipmpipe.org.