Screening and studying the growth-promoting characteristics of exopolysaccharide-producing plant growth-promoting rhizobacteria in alpine grassland
[Objective]To screen high exopolysaccharide-producing PGPR resources from the Zoige alpine grassland in order to provide valuable strains for developing Polysaccharide bacterial reagents suitable for Zoige alpine grassland and related products.[Method]At 16 ℃,high exopolysaccharide-producing PGPR was isolatedf rom the rhizosphere of Poa poophagorum and Elymus sibiricus in alpine grassland using selective media.Their taxonomic sta-tus was determined by 16S rDNA sequencing and phylogenetic analysis. The growth-promoting characteristics of the strain and exopolysaccharide were evaluated through inoculation tests.[Result]Three strains of exopolysaccha-rides-producing PGPR were identified from the rhizosphere of the two plants. Among them,strains NAHP4 and PBRS1 were notable for their high exopolysaccharides production,with levels of 1462.50 and 1337.50 mg/L,re-spectively. This strains exhibited growth-promoting properties,including nitrogen fixation and inorganic phosphorus solulisation. Exopolysaccharides promoted seed germination and seedling growth of Elymus sibiricus,through high concentration of exopolysaccharides significantly inhibited radicle growth (P<0.05). The inoculated strains NAHP4,NBHP13 and PBRS1 lypromotedroot development in Elymus sibiricus (P<0.05),with NAHP4 showing-the greatest effect.[Conclusion]Strain NAHP4,as a high exopolysaccharide-producing PGPR resource,has signifi-cant potential for developing polysaccharide bacterial reagents and related products suitable for the alpine grassland of Zoige.
万方数据
维普
