Phenotypes of the parental strains ER7A and CBS4C and the segregant 26B. (a) Scheme of the crossings to map mutations linked to the low glycerol yield phenotype. The initial parental cross of ER7A and CBS4C resulted in the segregant 26B with a low glycerol phenotype but without the ssk1E330N…K356N allele. The 26B segregant was crossed back with the inferior parent ER7A to find other linked mutations. (b) Glycerol and ethanol yield (on glucose) obtained in minimal medium with 5% glucose and in YP 10% glucose for the parental strains, ER7A and CBS4C, the segregant 26B, and the hybrid diploid 26B/ER7A. Three independent fermentations were performed with each strain.