【作者】 张洪涛；

【导师】 吾甫尔·米吉提；

【作者基本信息】 新疆大学 ， 生物化学与分子生物学， 2007， 硕士

【摘要】 为探索分离焮麻(Urtica cannabina L .)内生菌的最佳方法,并分离获得焮麻内生菌,探讨ERIC-PCR的引物在植物内生细菌分型应用中的优化及其与AP-PCR的结合在植物内生菌分子分型中的应用价值,筛选、获得对经济作物和农作物致病真菌具有拮抗能力的内生细菌,本研究首先采用碾碎法与剖开法对焮麻的内生菌进行分离,根据培养基上菌斑出现的数量确定碾碎法为适合分离焮麻的内生菌的方法。用碾碎法对焮麻的内生菌进行分离,分离获得12株内生细菌,2株内生真菌,依据形态学与生理生化特性,同时对比AP-PCR和ERIC- PCR图谱,对所分离内生细菌进行初步的分类鉴定,结果表明所筛选的12株内生细菌中2株为奈氏菌属,1株为葡萄球菌属,1株为链球菌属,3株为芽孢杆菌属,2株为短杆菌属,3株为肠杆菌属,并对ERIC-PCR引物进行了优化,优化引物后的ERIC-PCR条带稳定、丰富、清晰,AP-PCR与ERIC-PCR结合使用分型型效果明显增强。通过琼脂扩散法进行了研究,结果表明,XJUL-6对棉花黄萎病具有较强拮抗能力;XJUL-12对西瓜枯萎病具有拮抗能力;XJUL-8对黄瓜枯萎病具有拮抗能力,他们的抑菌圈分别达28mm,23mm,17mm。依据筛选、获得的内生菌的形态特征、生理生化检测、16SrDNA、G+Cmo1%,将XJUL-6鉴定为蜡状芽孢杆菌,将XJUL-12鉴定为枯草芽孢杆菌,将XJUL-8鉴定为苏云金杆菌。同时对XJUL-6的生物学特性进行初步研究,结果表明,36℃~38℃为其最适生长温度,pH6~8为其最适生长pH值,2%NaCl浓度为XJUL-6的最适生长NaCl浓度。更多还原

【Abstract】 In order to grope for the the best methods for isolating the endophyte of Urtica cannabina L. and acquire the endophye of Urtica cannabina L., probe into the optimized primer for ERIC-PCR and its value in the application of DNA analysis With AP-PCR, and attain antagonistic endophytic bacteria against pathogenic fungal of economic field crops. In this research, two of the isolation methods were used to isolated the endophyte of Urtica cannabina L., accrording to the number of the bacterial colony, the blendor methods as the best methods for isolating the endophyte of Urtica cannabina L. was decided and the endophyte of Urtica cannabina L. was isolated by using the blendor methods, 12 Strains of endophytic bacteria was screened, According to the observation of the morphology and the result of AP-PCR and ERIC- PCR, these strains were identifyed as Neisse ., Staphylococcus ., Streptococcus., Bacillus., Brevibacterium.s and Enterobacte.s, the electrophoresis strips of modified primer ERIC-PCR fingerprinting were abundant and clear, when ERIC-PCR was used for bacterial typing with AP-PCR,the effect of bacterial typing was enhanced obviously. The antagonistic endophytic bacteria against pathogenic fungal of economic field crops by the method of agar diffusion bioassay, 3 of these endophytic bacteria which have the ability of against the pathogenic fungal of economic field crops was acquired, XJUL-6 against Cotton Verticillium Wilt, XJUL-12 against Watermelon Wilt, XJUL-8 against fusarium wilt of cucumber, the microbiostatin diameter of XJUL-6 is 28mm, the microbiostatin diameter of XJUL-12 is 23mm, the microbiostatin diameter of XJUL-8 is 18mm.According to the observation of the morphology, the study of the physiological and biochemical, 16 SrDNA and G+C mo1% content, the XJUL-6 was identified as Bacillus cereus.,the XJUL-12 was identified as Bacillus subtilis.,XJUL-8 was identified as Bacillus thuringiensis.,At the same time, the biological characters of the bacteria was analyzed primarily, the results of pilot study shows that the optimum temperature range is 36℃~38℃, the optimum pH is pH6~8 and the optimum concentration of NaCl is 2%.更多还原