INTRAGENIC SUPPRESSION AT THE b2 LOCUS IN ASCOBOLUS IMMERSUS. I. IDENTIFICATION OF THREE DISTINCT GROUPS OF SUPPRESSION

A reversion study of EMS- or ICR170-induced ascospore color mutants in Ascobolus immersus is reported. Twenty-three new intragenic suppressors were isolated within the b2 locus. These are localized within three distinct groups on a genetic fine-structure map containing 21 identifiable sites. The pattern of reversion is discussed according to the known specificity of EMS and ICR170 in Ascobolus immersus.