Sources of Resistance to Gray Leaf Spot of Corn. S. T. COATES, Graduate Research Assistant, Department of Plant Pathology, University of Illinois at Urbana-Champaign 61801. D. G. WHITE, Associate Professor, Department of Plant Pathology, University of Illinois at Urbana-Champaign 61801. Plant Dis. 78:1153-1155. Accepted for publication 19 August 1994. Copyright 1994 The American Phytopathological Society. DOI: 10.1094/PD-78-1153.

In 1989, 1,396 corn (Zea mays) inbreds were evaluated for resistance to gray leaf spot at Urbana, Illinois, after inoculation with Cercospora zeae-maydis. Sixty-two inbreds were selected on the basis of low disease rating, restricted lesion type, and maturity most useful for breeding programs in the midwestern United States. In 1990, selected inbreds and F1 crosses between selected inbreds and the susceptible inbred FR1141, with the hybrid FR1141 x LH51 as a susceptible check, were evaluated. Crosses of FR114I with inbreds COO, CI88A, DS:74:1071, H110, M018W, Mo22, and TEX I had ratings that were nearly as good as or better than their resistant parent and significantly better than the susceptible hybrid FR1141 ? LH51. Many sources of resistance to gray leaf spot are available to improve inbreds used in corn hybrids in the midwestern United States.