一株羽毛针禾内生细菌的鉴定、功能及促生特性  

Identification,functions,and growth-promoting characteristics of an endophytic bacterium from Stipagrostis pennata

作　　者：焦诗雨 李旭东 张婷婷[1] 马磊[1] JIAO Shiyu;LI Xudong;ZHANG Tingting;MA Lei(College of Life Sciences,Shihezi University,Shihezi 832003,Xinjiang,China)

机构地区：[1]石河子大学生命科学学院,新疆石河子832003

出　　处：《微生物学通报》2022年第8期3179-3191,共13页Microbiology China

基　　金：国家自然科学基金(32060145,32060300,31760302,31560310)。

摘　　要：【背景】羽毛针禾是沙漠群落演替中的“先锋”草本植物,可在荒漠贫瘠地带繁殖,其生命力顽强、繁殖速度快、种子量大、扩散广。【目的】探究羽毛针禾具有促生效应的内生细菌资源。【方法】从种子中分离出内源性细菌Z1,并对其进行了生物化学、发酵和促生等方面的研究。【结果】Z1菌落呈黄色球形,不透明,中央有小突起,边缘褶皱而湿润,镜检成直杆状,表面有细鞭毛,大小范围为(0.5−1.0)μm×(1.0−3.0)μm。经革兰氏染色试验、靛基质、甲基红、氧化酶、淀粉生产水解试验、V-P试验、明胶液化学试验测定后均呈阳性,甲基红试验、尿素分解实验测定均呈现阴性,是泛生菌属(Pantoea)的细菌。Z1具有产吲哚乙酸的能力,单位产量为3.14 mg/L;而且具有溶磷、解钾、分泌铁载体的能力。Z1菌株最佳发酵培养基条件是:氮源为蛋白胨,碳源是溶性淀粉,无机盐为碳酸钙,pH 9.0。Z1接种小麦10 d后促生效果明显,叶宽、株高、根长等指标分别增长了60.0%、13.5%和8.0%;小麦幼苗的叶片含水量、总叶绿素含量、氮含量、可溶性蛋白等指标均有显著提升(P<0.05)。【结论】Z1是一株具有促生潜力的功能菌,可为利用微生物-植物互作和治理荒漠提供新资源。[Background]With tenacious vitality,Stipagrostis pennata is a pioneer plant species in the desert,which features fast reproduction,high seed yield,and wide spread of seeds.[Objective]To test the growth-promoting endophytic bacteria of S.pennata.[Methods]The endophytic strain Z1 was isolated from the seeds of S.pennata and the biochemical characteristics,fermentation conditions,and growth-promoting performance were explored.[Results]The colonies of Z1 were spherical,yellow,and opaque,with small protrusions in the center and wrinkled and wet margins.Microscopy showed that it was straight rod-shaped with fine flagella on the surface and the size of(0.5−1.0)μm×(1.0−3.0)μm.The Gram staining test,indole test,oxidase test,starch hydrolysis test,V-P test,and gelatin liquefaction test all demonstrated positive results,while the methyl red test and urea hydrolysis test showed negative result.Moreover,it was identified as a Pantoea strain.Z1 produced Indole-3-acid,with the yield of 3.14 mg/L.Moreover,it can solubilize phosphorus and potassium and secrete iron carrier.The optimum fermentation conditions of Z1 are as follows:peptone as nitrogen source,soluble starch as carbon source,calcium carbonate as inorganic salt,and pH 9.0.The wheat growth-promoting effect of Z1 was obvious 10 days after the inoculation,as the leaf width,plant height,and root length were 60.0%,13.5%,and 8.0%larger,respectively,and the leaf water content,total chlorophyll content,nitrogen content,and soluble protein of wheat seedlings were significantly increased(P<0.05).[Conclusion]Z1 is a functional bacterium with growth-promoting potential,which can be used for microbe-plant interaction and desertification control.

关 键 词：羽毛针禾 植物内生菌 泛生菌属 细菌鉴定 促生特性 

分 类 号：Q948.122.3[生物学—植物学]