VIEW ARTICLE

Role of Basidiospores as Propagules and Observations on Sporophores of Typhula idahoensis. Barry M. Cunfer, Experimental Aide, Department of Plant Pathology, Washington State University, Pullman 99163; G. W. Bruehl, Professor, Department of Plant Pathology, Washington State University, Pullman 99163. Phytopathology 63:115-120. Accepted for publication 27 July 1972. DOI: 10.1094/Phyto-63-115.

Basidiospores of Typhula idahoensis serve as inoculum in inciting snow mold of wheat and barley, but are of lesser importance than sclerotia. Sporulation in the field reaches its peak in mid-November, just prior to the start of the winter snow cover. Moisture and cool temperatures are important factors governing time of sporulation; day-length appears appears to be unimportant. After sporulation is complete, hyphae emerge from overmature sporophores which grow like hyphae from sclerotia. Sporophore length increased, sporophore color became lighter, and fewer basidia matured as depth of a straw layer covering sclerotia increased from 0 to 2.5 cm. The importance of these results to taxonomy of Typhula spp. is discussed. Basidiospores survived from 52 to 67 days at -1 to 10 C in a water-saturated atmosphere. Spore germination occurred from -1 to 15 C; 10 C was optimum for germ tube elongation. Typhula idahoensis grew as a saprophyte only when competition from other microorganisms was minimal. It is rarely found as a saprophyte on straw in the field.