ABSTRACT: Wild strains of Ascobolus michaudii produce 8-spored asci and uninucleate ascospores with thick anastomosing lines in the exosporium. A natural mutant in heterozygous condition with ascospores showing a thin verrucosely ornated exosporium was isolated. The exosporium types segregated in a ratio of 4:4 in the ascus, suggesting a typical Mendelian outcome controlled by a single allele pair. Six expected patterns were observed. Since mutant ascospores germinate normally, mutant homozygous cultures were obtained. Cultural studies using various media show no interference with the segregation pattern.

KEYWORDS: Ascobolaceae, Ascobolus, hybrid

NOMENCLATURAL NOVELTIES:
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