Relationship Between Field and Greenhouse Reactions of Soybean to Fusarium solani. P. A. Stephens, Former Graduate Research Assistant, Department of Agronomy, University of Illinois, Urbana 61801. C. D. Nickell, C. K. Moots, and S. M. Lim. Professor, Department of Agronomy, University of Illinois, Urbana 61801; Asgrow Seed Co., Stonington, IL 62567; and Professor, Department of Plant Pathology, University of Arkansas, Fayetteville 72701. Plant Dis. 77:163-166. Accepted for publication 26 October 1992. Copyright 1993 The American Phytopathological Society. DOI: 10.1094/PD-77-0163.

Field and greenhouse tests were conducted to determine the relationship between field and greenhouse reactions of soybean (Glycine max (L.) Merr.) to Fusarium solani (Mart.) Appel & Wollenw. emend. Snyd. & Hans., the causal organism of sudden death syndrome (SDS). Seedlings of 12 soybean cultivars, ranging from maturity group III to late-maturity group IV, were inoculated in the greenhouse with oat grains infested with F. solani. The same cultivars were evaluated for disease reaction in F. solani-infested microplots at Urbana, IL, and at infested field sites in central and southern Illinois. SDS leaf symptom severity for field-grown plants at the R6 growth stage and greenhouse leaf symptom severity at about 3 wk after inoculation were highly correlated (r = 0.60–0.91). Thus, inoculation of soybean seedlings with the oat grain culture in the greenhouse is a reliable method for evaluating reactions of soybeans to F. solani. In performance trials during 1990 and 1991 at four field sites infested with F. solani, no relationship was found between SDS severity and the agronomic traits yield, maturity, plant height, lodging, seed weight, and seed quality.