Apparent Self-Fertility in Neurospora crassa

Abstract

SUMMARY: Single ascospores which gave rise to temporarily self-fertile cultures were found in Neurospora crassa. Genetical and cytological evidence suggested that these ascospores were disomic for the chromosome containing the mating-type locus, the disomy having arisen following partial desynapsis at meiosis and unequal distribution of univalents. At some time after germination, the nuclei reverted to the haploid state. If the disomic ascospore had been heterozygous at the mating-type locus, two sorts of haploids might occur and fertility probably resulted from mating between these.