Occurrence of Stenocarpella macrospora Causing Ear Rot in Corn in the United States

Diplodia ear rot of corn is primarily caused by the fungus Stenocarpella maydis in the United States. Stenocarpella macrospora is a closely related fungus present in the U.S. but primarily associated with Diplodia leaf streak. S. macrospora is recognized as a major ear rot pathogen in South America and South Africa, but has infrequently been associated with ear rot in the U.S. This brief presents the first reports of Diplodia ear rot in Illinois and Tennessee. This is also the first confirmation of S. macrospora causing ear rot in the U.S. in over 60 years. Accepted for publication 19 May 2016. Published 15 June 2016.