小麦内生细菌促生菌株的筛选及其影响小麦生长的因子的相关性分析

以从小麦分离出的127株内生细菌为研究对象,体外试验测定内生细菌分泌生长素(Indole acetic acid,IAA)、解无机磷和有机磷的能力。在此基础上,利用内生细菌浸泡小麦种子,通过室外盆栽试验测定内生细菌对小麦的株高、根干重、茎叶的干重等指标的影响。分别采用聚类分析、判别分析和相关分析等综合统计分析法对测定数据进行分析。结果表明,127株内生细菌分为四大类,最优第一类有6个菌种,分别为RC79和SB127(Bacillus cereus)、LD161(Pseudomonas fluorescens)、RA135(B.subtilis)、JD204(P.putida)、RB132(B.megaterium),其小麦生长的株高、茎叶干重、根干重、解无机磷解磷圈、解有机磷解磷圈、解无机磷能力、解有机磷能力和分泌生长素含量等8个观察指标都高。第二类为18株,第三类为27株,第四类为76株。小麦生长指标(株高、茎叶干重、根干重)与菌株的解无机磷解磷圈、解有机磷解磷圈、解无机磷能力、解有机磷能力和生长素含量等指标之间具有显著正相关性。解无机磷和有机磷能力、分泌生长素含量对小麦生长有显著的促进作用。不同的内生细菌促进小麦生长的作用不同。选择能够分泌生长素含量高、解无机磷和有机磷能力强的最优内生细菌菌种,对促进小麦生长,防治小麦病害有积极意义。

Screening of wheat growth-promoting entophytic bacteriai strains and correlation analysis of factors influencing wheat growth

One hundred twenty seven endogenous bacterial strains isolated from wheat were used in this study.Quantity of IAA-secreting and ability to dissolve inorganic and organic phosphorus of endophytic strains were measured in vitro The height,dry weight ofroots,stems and leaves of entophytic bacteria soaked wheat seeds wheat in outdoor pot experiment were determined.Data analyses were performed using multiple statistical methods including cluster analysis,discriminatory analysis and comprehensive correlation analysis.The results showed that the 127 strains were divided into four categories.The top group included six strains,RC79 and SB127(Bacillus cereus),LD161(Pseudomonas fluorescens),RA135(B.subtilis),JD204(P.putida).RB132(B.megaterium),respectively.The height,dry weight of roots,stems and leaves,quantity of IAA-secreting,ability to dissolve inorganic and organic phosphorus of wheat were the highest.The second,third and fourth groups contained 18,27,76 strains respectively.The above eight indicators of all strains displayed a significant positive correlation effect.Ability to dissolve inorganic and organic phosphorus,quantity of IAA-secreting played a significant role in promoting wheat growth.Different entophytic bacteria had different effect on promoting the wheat growth.These endophytic bacterial strains could be adopted to promote wheat growth and control wheat diseases by improving the content of IAA,and inorganic and organic phosphorus.