关键词: 燕麦, 固氮菌, 溶磷能力, 土壤理化性质, 菌株功能多样性

Abstract: In order to explore the functional diversity of Avenna sativa L. rhizosphere microorganisms,the oat rhizosphere soil in the Sanjiangyuan region was used as object of this study. The physical and chemical properties of the rhizosphere soil were determined by conventional methods,and plant growth-promoting rhizobacteria (PGPR) were screened by plate coating method. The abilities of nitrogen fixation,phosphorus solubilization and indoleacetic acid production were explored. And the excellent strains were identified by 16S rRNA gene. Thirty one strains of excellent nitrogen-fixing bacteria,5 strains of phosphate-solubilizing bacteria and 13 strains of indoleacetic acid-producing bacteria were screened. There were significant differences in soil available nitrogen,total nitrogen,available phosphorus,total phosphorus,available potassium,total potassium,pH value and organic matter in different regions (P<0.01). There was a significant negative correlation between the total nitrogen content of rhizosphere soil and the number of PGPR (P<0.05). There was a significant positive correlation between the total phosphorus content,available potassium content,soil pH value,organic matter content and the number of PGPR (P<0.05). Six excellent PGPR strains were identified as Pseudomonas sp.,1 strain as Bacillus pumilus sp.,and 2 strains as Arthrobacter sp.. The number and functional diversity of oat rhizosphere strains in different regions,and the correlation between soil characteristics and PGPR amount.

Key words: Avenna sativa L., Azotobacter, Phosphate solubilization capacity, Soil physical and chemical properties, Functional diversity of strains