Gray leaf spot of Corn

Corn is the only species that can be affected by Cercospora zeae-maydis. There are two populations of Cercospora zeae-maydis, distinguished by molecular analysis, growth rate, geographic distribution, and cercosporin toxin production. Cercospora Zeae-Maydis differs from its cousin group Cercospera zeina sp. nov in that it has faster growth rate in artificial media, the ability to produce the toxin cercosporin, longer conidiophores, and broadly fusiform conidia. Cercospera zeina sp. nov affects corn in the Eastern Corn Belt and Mid-Atlantic States; Cercospora Zeae-Maydis is found in most corn producing areas of western Kentucky, Illinois, Indiana, Iowa, Wisconsin, Missouri, Ohio, and west Tennessee (Midwest). Both populations share the same symptoms and virulence, the ability of the fungus to invade the host.