为研究芒草不同部位细菌群落组成，采用稀释梯度平板法分离芒草根际土壤、根部、茎部和叶部可培养细菌，并分析其植物促生活性。16S rRNA基因序列分析表明，分离的86株芒草根际、内生细菌由放线菌门（Actinobacteria）、拟杆菌门（Bacteroidetes）、厚壁菌门（Firmicutes）和变形菌门（Proteobacteria）4个门、7个纲、22个属组成，不同部位细菌组成有所差异，其中短小杆菌属（Curtobacterium）在根际土壤和植物内部广泛存在，芽孢杆菌属（Bacillus）和根瘤菌属（Rhizobium）为根际土壤优势种群，伯克霍尔德菌属（Burkholderia）为根部优势种群，鞘脂单胞菌属（Sphingomonas）为茎部优势种群。分离菌株的植物促生特性分析表明，芒草根际和植物组织内部蕴含着丰富的产吲哚乙酸、产精氨酸脱羧酶和溶解难溶性磷酸盐等生物活性细菌，广泛分布于短小杆菌属、根瘤菌属、芽孢杆菌属、伯克霍尔德菌属、鞘脂单胞菌属等优势种群，且不同部位菌株促生特性和种类有所差别。

In order to understand the diversity of cultivable rhizosphere and endophytic bacteria associated with Miscanthus,strains with different colony morphologies were isolated using the dilution plate counting method and their plant growth-promoting activities were tested. Phylogenetic analysis based on partial 16S rRNA gene sequences indicated that 86 strains could be categorized into 4 phyla (Actinobacteria,Bacteroidetes,Firmicutes and Proteobacteria),7 classes,and 22 genera.The bacterial community compositions in the rhizosphere and plant tissues were different from each other.The dominant genus Curtobacterium was found to be well adapted to the rhizosphere,as well as to the root,stem and leaf.The dominant genera in the rhizosphere were Bacillus and Rhizobium,that in the root was Burkholderia,and in the stem was Sphingomonas.Plant growth-promoting activities analyses indicated that most strains displayed plant growth-promoting effects including IAA-production,phosphorus-solubilization,and arginine decarboxylaseproduction,and that the dominant plant growth-promoting bacteria were Curtobacterium,Rhizobium,Bacillus,Burkholderia and Sphingomonas.Plant growth-promoting activities and bacterial community composition were different between rhizosphere and plant endospheres.