东乡野生稻根际可培养细菌多样性及其植物促生活性分析  

Diversity and plant growth promoting activities of the cultivable rhizobacteria of Dongxiang wild rice(Oryza rufipogon)

作　　者：罗菲[1,2] 汪涯[2] 曾庆桂[1] 颜日明[1] 张志斌[1] 朱笃[1,2] 

机构地区：[1]江西师范大学生命科学学院/江西省亚热带植物资源保护与利用重点实验室,南昌330022 [2]宜春学院江西省天然药物活性成分研究重点实验室,江西宜春336000

出　　处：《生物多样性》2011年第4期476-484,共9页Biodiversity Science

基　　金：江西省科技攻关项目(2009ZDN10600)

摘　　要：为了解江西东乡野生稻(Oryza rufipogon)不同生育期根际可培养细菌群落多样性动态,从中寻找新的具有植物促生活性的微生物资源,分别于2009年5月、8月和11月采集了东乡野生稻秧苗期、抽穗期和成熟期根际土壤,采用稀释平板法分离到118株根际细菌,并检测了其植物促生活性。16S rRNA基因序列分析结合菌体形态观察表明:分离获得的118株细菌属于5大类群11个属20个种,其中29株(24.6%)属于变形菌门α亚群(α-Proteobacteria)、9株(7.6%)属于变形菌门β亚群(β-Proteobacteria)、37株(31.4%)属于变形菌门γ亚群(γ-Proteobacteria)、41株(34.7%)属于厚壁菌门(Firmicutes)、2株(1.7%)属于产水菌门(Aquificae)。芽孢杆菌属(Bacillus)、泛菌属(Pantoea)和鞘氨醇单胞菌属(Sphingomonas)的菌株数占优势。东乡野生稻根际可培养细菌多样性丰富,Shannon-Wiener指数为2.037–2.741,且细菌类群随水稻的生育期不同而改变。分离菌株的植物促生活性检测表明:东乡野生稻根际蕴含着丰富的固氮、溶磷、产IAA和分泌铁载体等生物活性细菌,其中泛菌属为优势根际促生细菌。此外,根际可培养细菌数量、促生细菌数量和植物促生活性等在东乡野生稻秧苗期开始升高,抽穗期到达高峰,成熟期下降。研究结果表明东乡野生稻根际土壤微生物多样性丰富,是根际促生细菌的重要资源库。In order to understand the diversity of cultivable rhizobacteria associated with Dongxiang wild rice at different growth stages and to discover new species and strains of plant growth-promoting rhizobacteria（PGPR）,we isolated 118 bacteria strains with different colony morphology using the dilution plate counting method and tested their plant growth promoting activities（PGPA） in May,August and November 2009.Phylogenetic analysis based on partial 16S rRNA sequences indicated that 118 strains clustered into 11 genera,and the dominant bacteria genera were Bacillus,Pantoea and Sphingomonas.The rhizobacteria displayed a high diversity with Shannon-Wiener indices of 2.037–2.741.PGPA analyses indicated that most strains displayed PGPR effects,including nitrogen-fixation,phosphorus-solubilization,IAA-production and siderophore-secretion,and that the dominant PGPR was Pantoea.Additionally,we found that the total amount and PGPA of cultivable rhizobacteria began to increase gradually at seedling stage of Dongxiang wild rice,and reached its peak at heading stage,then decreased at grain filling stage.Our results show that the diversity of bacterial communities in the rhizosphere soil of Dongxiang wild rice is abundant,and that the rich rhizobacteria may be a fascinating PGPR reservoir.

关 键 词：ORYZA RUFIPOGON 根际细菌 可培养细菌 群落多样性 植物促生活性 

分 类 号：S154.3[农业科学—土壤学]