Measuring the Relationship Between Northern Corn Leaf Blight and Yield Losses. A. D. Raymundo, Former Graduate Research Assistant, Department of Plant Pathology, University of Illinois, Urbana 61801. A. L. Hooker, Professor, Department of Plant Pathology, University of Illinois, Urbana 61801. Plant Dis. 65:325-327. Copyright 1981 American Phytopathological Society. DOI: 10.1094/PD-65-325.

Selected corn hybrids with different types of resistance to Helminthosporium turcicum were used to study the relationship between northern corn leaf blight and grain yield losses in a 2-yr study. Differences in infection rates and yields among inoculated and uninoculated hybrids were significant in 1977. In 1979, when much less disease occurred, significant differences were observed only in the areas under disease progress curves and in apparent infection rates, and neither were correlated with yield. The area curve multiple-point model appears appropriate for explaining the relationship between disease development and losses in yield in 1977 but not in 1979.

Keyword(s): Zea mays.