VIEW ARTICLE

Effect of Temperature and Fungicides on Survival of Corn Grown From Kernels Infected with Helminthosporium maydis. Thor Kommedahl, Department of Plant Pathology, University of Minnesota, St. Paul, Minnesota 55101; D. S. Lang, Department of Plant Pathology, University of Minnesota, St. Paul, Minnesota 55101. Phytopathology 63:138-140. Accepted for publication 9 August 1972. DOI: 10.1094/Phyto-63-138.

Kernels of corn infected with Helminthosporium maydis race T and sown early in May in the field resulted in 0-2% wilted seedlings, but those sown 2 weeks later yielded 0-30% (avg 8%) wilted seedlings despite a better seedling stand at the later date. In the greenhouse, a high temperature (24 C) increased losses from preemergence blight, root rot, and wilt, attributable to H. maydis, whether plants were maintained at 24 C or started at 18 C and transferred to 24 C. Seedlings that started growth at 18 C wilted 17-21%, but those that started at 24 C wilted 27-30%. A seed lot containing a high percentage of kernels infected with H. maydis was treated with 16 fungicides or combinations thereof. Of these, thiram plus either carboxin or benomyl gave the best seedling stands.