Molecular identification of Bacillus strains isolated from extreme dry-sand environment in Qinghai Chaidamu region and its lipopeptide compound analysis

[Objective] Microbe resource research in extreme environment.[Methods] Eight Bacillus strains isolated from Chaidamu extreme dry-sand region in Qinghai Province,were identified by polyphasic molecular taxonomy methods including rep-PCR(BOX-PCR and ERIC-PCR) fingerprints,as well as gyrB and 16S rDNA partial sequence analysis.Antagonistic activity detection and dual culture method screening were used to check antagonistic activity and bio-control efficacy of isolates.MALDI-TOF-MS were used to analyze lipopeptide compound of strains.[Results] Eight isolates were identified as Bacillus amyloliquefaciens(6 isolates),Bacillus axarquiensis(1 isolate),Bacillus atrophaeus(1 isolate).All of the isolates presented distinct antagonistic activity and bio-control efficacy to Sclerotinia sclerotiorum.MALDI-TOF-MS results showed that the strain DGL1(B.amyloliquefaciens) produced Fen-gycin,strain DGL6(B.axarquiensis)produced Surfactin,BacillomycinsD and Fengycin,while strain DCD1(B.atrophaeus) produced Surfactin and Fengycin.[Conclusion] The research provided Bacillus resources for further developing and application of bio-control strains ad-justing in dry-sand extreme environment of Qing-Tibet Altiplano.