On Monday (Aug. 16), South Carolina was confirmed as the latest stop for Asian soybean rust. As the season has progressed, soybean producers in the state watched the disease creep through neighboring Georgia and wondered when it would leap the border.
“No one has to wonder anymore,” said John Mueller, a Clemson University plant pathologist on Tuesday morning. “We’ve got it and I doubt anyone is shocked.”
The soybean rust was found in a commercial field in Hampton County. Recently, samples were pulled from the rust-harboring field several times.
“Over the last couple of weeks, this was the third sample from there,” said Mueller, based at the Edisto Research & Education Center in Blackville. “We normally run 25 to 30 leaves per field. In this instance, out of all those leaves, only one was found with a couple of pustules. So there’s no reason for a lot of excitement. The incidence was very minor.”
Hampton County is on the Savannah River on the Georgia line. “It’s almost directly across the river from Georgia’s Effingham County where rust has already been reported. So finding rust in Hampton County didn’t surprise me at all. We figured it would show up.
“The fact that we found it so early is a good indication that our rust detection system is working well.”
The South Carolina soybean crop is comprised of both full-season soybeans and those planted after wheat. In the southern half of the state, the full-season beans are about three weeks from finishing.
“Some of the producers are spraying for pests and mixing in a fungicide, mostly a strobilurin. On the early-planted beans — which look really good, incidentally — that should hold them through to harvest.
“For the late-planted crop, we’ll begin sampling more intensively and see what the rust does. We’ll respond accordingly.”
Many of South Carolina’s soybeans have already been treated with fungicides. “We’ve had an extremely wet year here — especially in the south-central part. We’ve had a lot of frogeye, septoria and downy mildew. So there’s already been fungicide spraying going on.”