FROM: John Mueller, Extension Soybean Pathologist, Edisto Research and Education Center
IN SOUTH CAROLINA RUST HAS NOW BEEN FOUND ON SOYBEAN IN COLLETON AND BAMBERG COUNTIES.
Joe Varn, Barnwell/Bamberg County Row Crop agent proved again that he has a knack for finding rust. He located rust on one leaf out of 90 from a field just east of Bamberg. The leaf had 4 pustules present.
Counties that have been surveyed but no rust found now include: Allendale, Anderson, Barnwell, Calhoun, Clarendon, Dillon, Darlington, Dorchester, Hampton, Horry, Jasper, Lee, Marion, Newberry, Orangeburg, Richland, Saluda and Sumter Counties.
This week’s weather is certainly perfect for the development of rust and many other foliar, stem and pod diseases such as Anthracnose, Phomopis and Purple Seed Stain. If you have soybeans with good yield potential that are between growth stages R-3 and R-5 this would be a good time to spray before any diseases develop. Remember, once you hit R-6 in a given field you cannot spray any fungicides.
Here are a few other survey results from this week:
Justin Ballew, Horticulture and Agronomy Agent for Dillon and Marion Counties sent in leaves from two fields in Dillon County. He collected 50 leaves from each field but no rust was found on either field.
Trish DeHond, Area Agronomy Agent, Darlington submitted 50 leaves in a sample from the Hartsville area but no rust was found.
Hannah Mikell, Clarendon County Agronomy Agent sent in leaves from 2 fields in Clarendon County. Fifty leaves were examined from each field but no rust was found.
With the help of David Gunter, Feed Grains Specialist, I examined over 300 leaves from plots on the Edisto REC in Barnwell County. No rust was found.
If you would like an update on the occurrence of soybean rust across the United States check out http://sbr.ipmpipe.org .