TAXONOMY OF PENICILLIUM-CHRYSOGENUM AND RELATED XEROPHILIC SPECIES, BASED ON ISOZYME ANALYSIS

Eighty-four isolates of Penicillium chrysogenum and related species we re examined by isozyme analysis. Four main groups could be defined by cluster analysis; P. chrysogenum var. chrysogenum, P. flavigenum sp. n ov., P. chrysogenum var. dipodomyis and P. nalgiovense. P. flavigenum is described as new species, and P. chrysogenum var. dipodomyis raised to species level as P. dipodomyis. The genetic distance between these groups was calculated by employing a formula that accounts for the di fferences in alleles and loci obtained by isozyme analysis of these fu ngi. The genetic distances and cluster analysis suggest that the group s should be considered as four separate species. The practical implica tion of the separation and the ecological characteristics of the four species are discussed.