Effects of Dinitroaniline Herbicides, Carboxin-Pentachloronitrobenzene Seed Treatment, and Rhizoctonia Disease on Soybean. E. M. Bauske, Graduate Research Assistant, Department of Plant Pathology, University of Illinois, Urbana-Champaign 61801. H. W. Kirby, Professor, Department of Plant Pathology, University of Illinois, Urbana-Champaign 61801. Plant Dis. 76:236-239. Accepted for publication 8 September 1991. Copyright 1992 The American Phytopathological Society. DOI: 10.1094/PD-76-0236.

The effect of trifluralin, pendimethalin, and ethalfluralin and disease caused by Rhizoctonia solani on soybean (Glycine max) was determined with field and growth chamber studies. In field studies, oats infested with R. solani placed in furrow at planting significantly reduced plant growth variables. No significant interactions were observed between herbicides and inoculum treatments. Effects of inoculum were significantly reduced with carboxin-penta-chloronitrobenzene seed treatment. In growth chamber studies, steamed and nonsteamed field soil were used. No significant interactions were found between herbicides and plant growth variables in steamed soil. Significant interactions between herbicides and inoculum treatments affecting root and hypocotyl weight occurred in nonsteamed soil. Root and hypocotyl weights were significantly lower in infested soil than in noninfested soil in the absence of herbicides. No similar significant differences were observed in treatments where herbicides were added to the soil.