Genetic diversity and phylogeny of siderophore producing bacteria isolated from cotton rhizosphere in China's Xinjiang.

【Objecive】 The aim of this paper is to reveal the genetic diversity of siderophore producing bacteria in Xinjiang provincial cotton rhizospheric soils,and to screen some effective siderophore strains.【Method】 The genetic diversity of 68 siderophore strains isolated from cotton rhizospheric soil was analyzed by BOXAIR-PCR and 16S rRNA PCR-RFLP.Furthermore,the phylogeny of the representative strains was determined by 16S rRNA sequences analysis.【Result】 Analysis of BOXAIR-PCR showed that all the strains were divided into 11 BOXAIR-PCR groups.The results of 16S rRNA PCR-RFLP analysis suggested that the genetic diversity was also existed and 10 genotypes were formed.The 16S rDNA sequence of representative strains was analyzed and the phylogenic tree was constructed,and the results revealed that these siderophores belonged to seven different genera,ie.Pseudomonas,Enterobacter,Acinetobacter,Bacillus,Alcaligenes,Brachybacterium and Pantoea,and strains belonged to genus of Pseudomonas was the predominant one among them.【Conclusion】 The genetic diversity of the siderophore strains isolated from cotton rhizospheric soils in Xinjiang province is high.