Differentiation of Beauveria bassiana isolates from the darkling beetle, Alphitobius diaperinus, using isozyme and RAPD analyses

Two natural genetic markers, isozymes and RAPD, were utilized to differentiate 24 strains of Beauveria bassiana (Deuteromycotina: Hyphomycetes) collected from the darkling beetle, Alphitobius diaperinus (Coleoptera: Tenebrionidae), from poultry houses in North Carolina and West Virginia. Nine enzyme systems were screened, of which alkaline phosphatase, alpha- and beta-esterase, and glucose phosphate isomerase gave well-resolved, scorable bands. A total of 26 isozyme bands was generated by these four enzymes which partitioned the 24 strains into 14 classes. Three classes were shared by two or more strains while the rest of the strains had distinct electrophoretic profiles. Ten RAPD primers, selected from 72 that were screened, produced 141 bands from the 24 strains and separated each as a unique class. While both systems were able to detect variation present among the 24 strains hom different regions in North Carolina and West Virginia, RAPD markers provided better resolution of the differences between strains. Variation was detected not only within and among strains from different regions but also among strains collected from a given insect host. (C) 1998 Academic Press.