VIEW ARTICLE

Ecology and Epidemiology

Factors Affecting Suppression of Rhizoctonia solani in Container Media. E. B. Nelson, Graduate research associate, Department of Plant Pathology, Ohio Agricultural Research and Development Center, Wooster 44691; H. A. J. Hoitink, professor, Department of Plant Pathology, The Ohio State University, Columbus 43210. Phytopathology 72:275-279. Accepted for publication 5 May 1981. Copyright 1982 The American Phytopathological Society. DOI: 10.1094/Phyto-72-275.

Container media containing high levels of composted hardwood bark (CHB) suppressed Rhizoctonia damping-off on Celosia and radish. Container media containing pine bark were only mildly suppressive and media containing high levels of peat were conducive. Increasing seedling density from 245–735 seedlings per square meter did not increase damping-off in either CHB or peat media. Substitution of 0, 28, 50, 72, and 100% of the CHB with peat resulted in a dilution of suppression. The suppressive effect of CHB was not detectable regardless of propagule size when hosts were exposed to inoculum densities of >20–25 propagules per gram.