湘莲根际促生菌的筛选及其效应研究

Screening of Plant Growth Promoting Rhizobacteria of Xiang Lotus(Nelumbo nucifera Gaertn.)and Their Promoting Growth Effects

为获得湘莲根际促生菌(Plantgrowth promoting rhizobacteria,PGPR)并明确其促生特性,试验从湘莲根际土壤中分离出7株固氮解磷菌,通过对其功能指标的对比挑选出菌株XL7,其具有良好的固氮解磷和产IAA能力。经鉴定该菌株为高地芽孢杆菌(Bacillus altitudinis)。通过种子萌发、盆栽试验测定菌株对湘莲的促生效应。结果表明:接种XL7能促进种子的萌发,发芽势、发芽率、苗长、苗重和不定根重均高于对照;土壤中矿质态氮、速效磷和速效钾分别提高了5.3%、31.8%和26.1%;莲幼苗植株生物量、全氮、全磷和全钾分别增加了25.0%、18.3%、80.5%和38.7%。这表明该多功能菌株对湘莲具有良好的促生作用。

In order to obtain plant growth promoting rhizobacteria(PGPR)and confirm their promoting properties,we isolated 7 nitrogen-fixing and phosphorus-solubilizing bacteria from rhizosphere soil of Xiang lotus(Nelumbo nucifera Gaertn.),and selected strain XL7 by comparing their functional parameters.XL7 has good capacity of nitrogen fixing and phosphorus solubilization and IAA production.The strain was identified as Bacillus altitudinis.The growth-promoting effect of the strain on Xiang lotus was determined by seed germination and pot experiments.Results showed that inoculation with XL7 could promote seed germination,under which the germination energy,germination rate,seedling length,seedling weight and adventitious root weight were all higher than CK.Mineral nitrogen,available phosphorus and available potassium in the soil increased by 5.3%,31.8%and 26.1%,respectively.The biomass,total nitrogen,total phosphorus and total potassium of the lotus seedlings increased by 25.0%,18.3%,80.5%and 38.7%,respectively.The multifunctional strain has good growth promoting effect on Xiang lotus,and has broad agricultural application prospect.