FROM: John Mueller, Extension Soybean Pathologist, Edisto Research and Education Center
RUST WAS FOUND LAST WEEK ON SOYBEAN IN SOUTH CAROLINA IN A FIELD IN COLLETON COUNTY
Last week rust was found in a field in Colleton County. We have agents actively surveying in several other counties in the Savannah Valley. Here are this week’s results:
Joe Varn, Barnwell/Bamberg Ag agent returned to the “rust” field in Colleton County on Tuesday August 23rd and collected another 100 leaves. He found rust on only 2 leaves and again there were only 1 or 2 pustules present on the leaves.
Joe also checked a second field yesterday in Colleton County. He collected and examined 50 leaves but found no rust.
Andrew Warner, Allendale/Hampton Ag Agent collected leaves from two fields last week. He collected 25 leaves from a field at R-3 growth stage in Hampton County but found no rust. He also collected 25 leaves from a field at R-4 growth stage in Allendale and found no rust.
Andrew checked 40 leaves from a second field in Allendale yesterday that is at R3 growth stage but found no rust.
Jonathan Croft, Orangeburg County Ag Agent checked three fields last week. He checked 100 leaves from a field at growth stage R4 in Orangeburg County but found no rust. He collected 100 leaves from a field at R5 growth stage in Dorchester County and found no rust. He also collected 100 leaves from a field at R5 near Bowman and found no rust.
So, of the seven fields we have been checking on an almost weekly basis we have found only 1 field with rust and the level of rust in that field is very low. At this time, rust has not been found in the Pee Dee region. This week’s weather for the most part is not conducive to spore germination or disease spread. Rust develops best when we have morning dews that last up to 9:30 or 10:00 or even later and/or we have overcast days and rain.
If you would like an update on the occurrence of soybean rust across the United States check out http://sbr.ipmpipe.org .