Southern rust was observed in the University of Kentucky Hybrid Corn Performance Test in Webster County, KY on July 18, 2016. The disease was observed by the keen eyes of UK Plant Pathology interns, Andrew Gennett and Conner Raymond, and confirmed by Brenda Kennedy at the UK Plant Disease Diagnostic Laboratory in Princeton. To my knowledge, this is the first confirmed observation of southern rust in Kentucky for the 2016 season.
Information about foliar fungicides, southern rust, and other foliar corn diseases is available in an article appearing in last week’s issue of Kentucky Pest News (KPN)
Southern rust may be difficult to differentiate from common rust, but identification of this disease is crucial since most corn hybrids are susceptible to southern rust. It is important to work with your local county Extension agent in submitting any suspect samples to the UK Plant Disease Diagnostic Laboratory. In addition, a free online webcast is available that shows ways to differentiate southern rust vs. common rust of corn.
By Carl A. Bradley, Extension Plant Pathologist