GENETICS OF SORDARIA FIMICOLA. IX. LINKAGE GROUP II

Ten mutant sites have been located in linkage group II of Sordaria fimicola, nine of them affecting fertility. Two different regions of the chromosome are marked with allelic mutations or mutant sites in closely linked loci involved in sexual reproduction. Mutants of one of these two regions also have an arginine deficiency. Crosses between the self-sterile mutants of each region yield hybrid perithecia containing asci with four spores of each parental genotype and few or no asci with recombinant spores. The bearing that these findings have upon the evolution of heterothallism is discussed.