COMPARISON OF METHODS FOR ISOLATING RHIZOCTONIA FROM SOIL

Abstract

Four methods described in the literature for isolating Rhizoctonia spp. from soil were employed simultaneously with two naturally infested soils. Each method had certain distinct advantages and characteristics which would suggest its use under particular circumstances. The infected host method was best for studies on the range of clones of the fungus pathogenic to certain plants. The immersion tube method recovered a limited number of clones of the fungus. The debris particle method in conjunction with the buckwheat colonization method gave the most complete information since the debris particle method reflected the status of the quiescent rhizoctonia in soil and the buckwheat colonization method, the active. Clones of the fungus obtained by the four methods varied from non-pathogenic to strongly pathogenic on live species of plants.