【摘要】 从款冬根际及根系筛选出PGPR菌株，研究其促生长特性及作用，以期为款冬的丰产栽培提供潜力菌株。采用稀释平板法筛选PGPR菌株，检测其促生特性，通过形态、生理生化指标、BIOLOG及16S rDNA进行鉴定，结合款冬盆栽试验检测其接种效应。结果表明，从款冬根际以及细根中筛选出3株高产IAA菌株KD6B、KD17B和KD26B，鉴定为Enterobacter cloacae subsp. dissolvens、Klebsiella oxytoca和K. areogenes，具解磷、产嗜铁素、耐盐、耐旱及拮抗作用；接种3株菌能显著增加款冬幼苗叶片数、叶面积、根长和根际土壤微生物群落多样性指数，其中KD17B效果最明显，叶片数、叶面积和根长分别增长了36.36%、29.21%、54.07%，平均颜色变化率、Shannon指数和McIntosh指数最大。3株PGPR对款冬有显著促生作用，对其根际土壤微生物群落结构有调控作用，在款冬的丰产栽培中具较高应用价值。更多还原

【Abstract】 Growth-promoting characteristics and effects of plant growth promoting bacteria(PGPR) strains isolated from the rhizosphere and root system of Tussilago farfara were studied, in order to provide potential strains for the high-yield cultivation of T. farfara. PGPR strains were obtained by dilution-plating method, and their growth-promoting characteristics were analyzed. These strains were identified by morphological,physiological and biochemical BIOLOG and 16s rDNA sequence. The inoculation effects of these strains on seedlings of T. farfara were examined by a pot-culture experiment. The results showed that three highyielding IAA strains were selected from the rhizosphere soil and roots of T. farfara, named Enterobacter cloacae subsp. dissolvens(KD6B), Klebsiella oxytoca(KD17B) and K. areogenes(KD26B), which had effects of solubilize phosphorus, produce siderophore, salt tolerance, drought tolerance and antagonism. Three strains significantly increased the number of leaves, leaf area, root length and diversity index of rhizosphere soil microbial community of T. farfara seedlings. Among them, KD17B had the most obvious effect, with the number of leaves, leaf area and root length increasing by 36.36%, 29.21% and 54.07% respectively, and the average color change rate(AWCD), Shannon index and McIntosh index were the largest. Three PGPR strains have significant growth-promoting effects on T. farfara and regulate the structure of rhizosphere soil microbial community, which have high application value in the high-yield cultivation of T. farfara.更多还原