摘要
采用传统的分离培养手段从高加索三叶草种子内分离筛选出内生细菌B7,通过生理生化以及16S rDNA进行分子鉴定,结果表明菌株B7属于泛菌属(Pantoea sp.).菌株B7在15%PEG6000干旱胁迫下能够正常生长,表现出较强的耐旱能力;在pH值5～11范围内均能生长,有良好的耐酸碱能力;兼具产IAA、分泌铁载体、固氮和溶磷能力,其中产IAA能力高达0.28 g/L,溶解有机磷、无机磷和产铁载体的指数分别是3.15、2.91和2.63,速率分别为2.15、1.91和1.63.菌株B7具有良好的促生效果,显著提高了高加索三叶草的株高、地上鲜重、地下鲜重与干重、叶长、叶宽、叶片数、叶面积、根长、根投影面积、根表面积、根尖数,促进了高加索三叶草的生长发育.
Abstract
The endophytic bacterium B7 was isolated and screened from the seeds of Caucasian clover by traditional isolation and culture methods.The molecular identification was performed by physiological and biochemical characteristics and 16S rDNA,and the results showed that B7 belonged to the genus Pano-bacterium(Pantoea sp.).The strain B7 could grow normally under 15%PEG6000 drought stress,show-ing strong drought tolerance.It could grow in pH range of 5 to 11,with good acid and alkali tolerance.It had the ability to produce IAA,secrete iron carrier,fix nitrogen and dissolve phosphorus,among which the IAA production ability was as high as 0.28 g/L,the dissolution indexes of organic phosphorus,inorganic phosphorus and iron carrier were 3.15,2.91 and 2.63,and the rates were 2.15,1.91 and 1.63,respec-tively.The strain B7 had good growth-promoting effect,which significantly improved the plant height,aboveground fresh weight,underground fresh and dry weight,leaf length,leaf width,number of leaves,leaf area,root length,root projected area,root surface area as well as number of root tips of Caucasian clover and promoted the growth and development of Caucasian clover.
基金项目
国家自然科学基金项目(31960353)
2023国家草业技术创新中心(筹)重大创新平台建设专项基金(CCPTZX2023K01)
维普
万方数据