Pure Culture Studies of Fruiting and Sporulation in a Clavarioid Fungus, Pterula Sp

An isolate of Pterula sp. from Trinidad, West Indies, fruited and sporulated readily on a potato dextrose-yeast extract medium. Fruit bodies grew 30-50 mm tall in 30 days. The influence on fruiting of different volumes of medium and of light and darkness, the tropic responses of the fruit bodies, and the periodicity of spore release were studied. Fruiting and spore formation occurred in darkness or alternating light and darkness although the fruit bodies were smaller in the dark. Fruit bodies were positively phototropic and negatively geotropic. In a 12-hr photoperiod basidiospore release was greatest in the second half of the 12-hr dark period and absent in the last half of the light period. Spore germination occurred readily on a nutrient medium, more slowly on water agar. Single-spore cultures fruited. The possible relationship of the results obtained with Pterula sp. to those obtained in other hymenomycetes is discussed.