Further Studies on Spontaneous Variations of Torula pulcherrima

Abstract

Variations in this chromogenic asporogenous yeast were studied through 6 further giant colony generations. New variants observed are colonies with red soluble pigment, and white colonies with "craters," which are looked upon as rough types. White variants were much more stable than the red parent type. In general white variants arise from red in the actively growing cells at the periphery of the colony, whereas red variants arise from white in the aged cells at the center of the colony.