小麦根圈细菌中PGPR的筛选及其初步鉴定

SCREENING AND IDENTIFICATION OF PGPR STRAINS ISOLATED FROM THE RHIZOSPHERE OF WINTER WHEAT( Triticum aestivum L.)

通过不灭菌砂培，比较了３１ 株荧光色素产生菌和２２ 株耐寒细菌接种处理麦种后对麦苗株高、地上部干重及总干重的影响，获得具有小麦生长刺激作用的荧光色素产生菌和耐寒细菌各３ 株，其中的２ 株耐寒细菌也是荧光色素产生菌。通过离体拮抗试验，得到了７ 株对小麦根腐病原菌及５ 株对小麦全蚀病原菌有抑制作用的根圈细菌。选取分别对小麦土传根腐病原菌和全蚀病原菌具有较强拮抗作用的２ 个菌株Ｘｌ６ 和Ｘｙｇ９（ 该菌株对麦苗生长也有较强刺激作用） 进行了初步鉴定，分别属于Ｐｓｅｕｄｏｍｏｎａｓｆｌｕｏｒｅｓｃｅｎｓｂｉｏｖａｒ

The effects of 31 strains of fluorescent pseudomonads and 22 strains of psychrotrophic bacteria which were isolated from wheat rhizosphere in the field conditions inoculated to wheat seeds on plant height,dry weight of shoot and total dry weight have been compared. Three strains of each group of the above bacteria with plant growth promoting role were screened; two strains of psychrotrophic bacteria also could produce fluorescent pigment on Kings B medium. Seven strains antagonistic to wheat root rot pathogen( Helminthosporium sativum ) and five strains resistant to take all pathogen ( Gaeummanomyes graminis var tritic ) were obtained by in vitro antagonistic experiments. The natural resistance of 13 strains to 9 kinds of antibiotics was detected. Strains Xl?6 and Xyg?9 antagonistic to H.sativum and G.g.t. were identified as Pseudomonas fluorescens biovar Ⅰ and Ⅲ, respectively.