Fungicidal Control of Eutypa armeniacae Infecting Concord Grapevine in Michigan. E. H. Gendloff, Graduate Research Assistant, USDA, ARS, Department of Botany and Plant Pathology, Michigan State University, East Lansing 48824. D. C. Ramsdell, Professor of Plant Pathology, and C. L. Burton, Research Plant Pathologist, USDA, ARS, Department of Botany and Plant Pathology, Michigan State University, East Lansing 48824. Plant Dis. 67:754-756. Accepted for publication 2 December 1982. Copyright 1983 American Phytopathological Society. DOI: 10.1094/PD-67-754.

Field trials were conducted at four different dates in the winter and early spring of 1979–1980 and also in 1981 in a commercial vineyard at Lawton, MI. In the 1979–1980 trials, a benomyl 50WP spray of 4.8 g/L water (0.5 L per vine) gave significant control of ascospore infection by Eutypa armeniacae when pruning wounds on 2-yr-old wood were inoculated either on the day of pruning and spraying or 14 days later. A lower rate of benomyl 50WP, two rates of captafol 4F, and a biological control treatment of Fusarium lateritium gave little or no control. Pruning wounds declined in susceptibility over the 14-day period. No differences in susceptibility to infection were noted among the four dates of pruning. In the 1981 trial, benomyl 50WP showed significant disease control at 1.2 and 9.6 g/L water compared with water-treated control vines.