Random and repetitive primer amplified polymorphic DNA analysis of Bacillus sphaericus

A comparative study of 15 strains representing the five homology groups of Bacillus sphaericus mas performed by two PCR methods: RAPD and rep-PCR fing erprinting. The PCR analysis performed with primers corresponding to the na turally occurring repetitive sequences REP, ERIC and BOX, as well as with t hree random primers, showed highly variable patterns and allowed differenti ation of the strains studied. This demonstrated the high discriminative pow er of the methods. The cluster analysis revealed a low level of similarity between the different homology groups, and within groups I and III, which i s evidence of the high genetic heterogeneity of the species B. sphaericus. Close genetic relatedness was observed for the representatives of group IIA , pathogenic to mosquitoes, which supports the idea for differentiation of this group as a separate species.