Figure 1.—

Petites occur at a higher frequency in most common laboratory strains. (A) A 2-day-old YEPD colony of the laboratory strain BY4716 and of the vineyard strain RM11-1a were diluted appropriately and plated onto indicator YEPDG plates to distinguish between petite and grande colonies. Pictures were taken after 5 days of growth. (B) Petite frequencies are presented for several laboratory and natural isolate strains (described in Tables 1 and 3). The petite frequency was determined for four independent isolates of each strain and is represented by a shaded dot. Each solid line represents the median petite frequency. (C) The petite frequencies for diploid strains of the BY (UCC8088-1), RM (UCC8062-1), and hybrid BY × RM (UCC8413) genetic backgrounds.