Factors Affecting Soybean Seed Quality in Illinois. E. G. Jordan, USDA Plant Pathologist and Assistant Professor, Department of Plant Pathology, University of Illinois at Urbana-Champaign, Urbana 61801. J. B. Manandhar, Graduate Research Assistant, P. N. Thapliyal, Visiting Associate Professor, and J. B. Sinclair, Professor, Department of Plant Pathology, University of Illinois at Urbana-Champaign, Urbana 61801. Plant Dis. 70:246-248. Accepted for publication 3 September 1985. Copyright 1986 The American Phytopathological Society. DOI: 10.1094/PD-70-246.

Soybean seeds harvested from 18 northern and 12 southern Illinois soybean disease-monitoring plots were assayed for quality from 1978 to 1981. Weather and soil conditions in northern plots were more conducive to plant growth and high-quality seed production than those in southern plots. Seed weight and percent radicle emergence were greatest from northern plots, whereas numbers of fungus-infected and noninfected-nonviable seeds were greatest from southern plots. Numbers of seeds infected by Aspergillus spp., Chaetomium spp., and Phomopsis spp. were highest in northern plots, whereas numbers of seeds infected by Alternaria spp., Cercospora kikuchii, Cladosporium spp., Colletotrichum spp., Fusarium spp., Macrophomina phaseolina, Nematospora coryli, Penicillium spp., and Phoma spp. were highest in southern plots.