Linkage group analysis in Aspergillus niger

A variety of genes for auxotrophic, morphological and resistance characters of Aspergillus niger have been assigned to eight linkage groups by haploidisation of heterozygous diploids. Methods of linkage group analysis are described that avoid disturbance of linkage data by interference of mitotic crossing-over. Four master strains for linkage group analysis were constructed with markers for the eight linkage groups in such a way that a great variety of mutants can be analysed with one of them. Moreover, over 400 strains with various combinations of more than 70 markers can be used for specific situations. Strategies for analysis of production strains are discussed. The master strains and other strains with genetic markers are available and a list with genotypes can be sent on request. Correspondence to: C. J. Bos