The Influence of Heterokaryotic Conidia on the Selective Recovery of Somatic Diploids in Aspergillus niger

SUMMARYForced heterokaryons between auxotrophic strains of Aspergillus niger produce rare (10-4) heterokaryotic conidia which can interfere with the selective recovery of somatic diploid strains which occur with a frequency of approximately 10-6. Replating of conidia derived from prototrophic colonies which develop on the selective minimal medium results in enrichment for the somatic diploid since virtually all of the diploid conidia can germinate on the selective medium whereas only 10-4 of the conidia derived from heterokaryotic colonies can germinate on the same medium.