Greenhouse and Field Evaluation of Fusarium solani Pathogenicity to Soybean Seedlings. J. F. Killebrew, Extension Plant Pathologist, Mississippi State University, Mississippi State 39762. K. W. Roy, G. W. Lawrence, K. S. McLean, and H. H. Hodges. Professor of Plant Pathology, Assistant Professor of Plant Pathology, Graduate Research Assistant, Department of Plant Pathology and Weed Science, and Professor of Agronomy, Department of Agronomy, Mississippi State University, Mississippi State 39762. Plant Dis. 72:1067-1070. Accepted for publication 28 June 1988. Copyright 1988 The American Phytopathological Society. DOI: 10.1094/PD-72-1067.

Koch’s postulates were completed with Fusarium solani under both greenhouse and field conditions. Root rot was the most prevalent and damaging symptom caused by the fungus. Five F. solani isolates tested were pathogenic when inoculated on soybean, and each was reisolated from inoculated, symptomatic plants. Isolates differed in virulence. Disease severity was not substantially changed when F. solani and soybean cyst nematode (Heterodera glycines) were inoculated on soybean in combination, as compared with F. solani or soybean cyst nematode alone. The fungus reduced yield under field conditions. Disease severity was greater with poor-quality seeds inoculated with F. solani than with inoculated high-quality seeds.

Keyword(s): Glycine max, seed quality.