Genetic diversity analysis of rep-PCR genomic fingerprinting of Lysobacter spp.

Lysobacter. spp. are considered as important biocontrol bacteria, due to their antagonistic activity against many pathogenic fungi, bacteria and nematodes. Rep-PCR was used to analyze the genetic diversity of 12 Lysobacter strains. These strains included Lysobacter antibioticus (HY, 13-1, 13-6, 6-B-1, 13-B-1, 6-T'-4, LJ6-3, LJ6-4 and LR9-3), Lysobacter enzymogenes (DH3, 1-T-1-4) and Lysobacter capsici (LG18) isolate from different regions in Yunnan province of China. Rep-PCR was performed using DNA amplification with primers based on short bacterial repetitive elements (ERIC, BOX, IS1113 and J3). The genetic diversity was analyzed through rep-PCR, molecular fingerprint clustering analysis and UPGMA to construct phylogenetic tree. The results show that when the genetic distance was 0.59, IS1113-PCR could cluster the Lysobacter strains as 3 species: L. antibioticus, L. enzymogenes and L. capsici. The 3 species had obvious differences between each other and the rep-PCR technique could be used to detect genetic variation between different Lysobacter strains, identification and strain classification.    Key words: Lysobacter, Rep-PCR, genetic diversity.