Soybean rust confirmed in Tennessee

Asian soybean rust (ASR) was confirmed today in three West Tennessee counties: Gibson, Obion and Weakley.

The following is from USDA's ASR web site:

Asian soybean rust was found in West Tennessee on soybean leaf samples taken from several fields in Gibson, Obion and Weakley counties on Thursday, October 12. After the soybean plants were sampled, a hard frost occurred in West Tennessee, and most remaining green leaf tissue was destroyed.

Double crop soybeans are mostly past the R7+ stage.

The disease samples -- a few rust pustules -- were found on soybean leaves and visually identified with a microscope at the UT Extension lab at Jackson. The samples were then tested with the "QuickStix" method by Dr. Melvin Newman, Department of Entomology and Plant Pathology in Jackson. Final confirmation that the pustules were Asian soybean rust was determined by polymerase chain reaction (PCR) testing in Dr. Kurt Lamour's lab at UT Institute of Agriculture in Knoxville.