【摘要】 从质粒pUC1965得到含有几丁质酶基因的6.5 kb DNA片断,将该基因与大肠杆菌-荧光假单胞杆菌穿梭质粒pDSK519连接,获得重组质粒pDSK51965。重组质粒转入荧光假单胞杆菌(Pseudomonasfluorescence)P5,获得工程菌株P.fluorescence P5-1。与野生菌株相比,平板拮抗实验表明, 工程菌株对小麦全蚀病(Gaeumannomycesgraminisvar. tricici)、水稻纹枯病(Rhizoctoniasalani)和棉花立枯病(R.salani )抑菌效果明显提高;盆栽防病实验表明,工程菌株显著地提高了对水稻纹枯病及棉花立枯病的防效,并提高了对小麦全蚀病的防效。更多还原

【Abstract】 Pseudomonas fluorescence P5 was isolated in Yunnan Province and proved as a biocontrol agent of plant diseases. The aim of this study was to enhance the biocontrol effect of this strain by introduction of a chitinase gene. A 6.5 kb DNA fragment containing chitinase gene was inserted into vector pDSK519 to construct a new plasmid, pDSK51965, which was introduced into P. fluorescence P5, resulting in a new strain named P5-1. Restriction digestion and chitin plate culture confirmed that P5-1 contained a functional chitinase gene. Compared with wild type P5 in pot experiment, P5-1 had increased effect against rice sheath blight and cotton damping-off caused by Rhizoctonia solani. It also increased the effect on suppression of wheat take-all caused by Gaeumannomyces graminis var. tritici.更多还原