论文部分内容阅读
从甜瓜根际土壤、牦牛粪、蚯蚓粪等样品中分离出245株细菌,用平板对峙法筛选出14株对甜瓜枯萎病菌具有良好抑制作用的菌株,分别采用管碟法和凹玻片法测定拮抗细菌发酵液对甜瓜枯萎病的抑制效果和对甜瓜白粉病菌、甜瓜霜霉病菌孢子囊萌发的抑制效果。抑菌试验结果显示,菌株FCJ2发酵液对甜瓜枯萎病菌的抑制率为64.7%,对甜瓜白粉病菌、甜瓜霜霉病菌孢子萌发抑制率为62.3%、49.2%。盆栽试验结果显示,FCJ2对甜瓜枯萎病、甜瓜白粉病和甜瓜霜霉病的防效分别为88.5%、93.6%和82.6%,与农药对照组相比均具有显著差异(P<0.05)。经形态特征鉴定、生理生化特征鉴定及16S rDNA序列分析,确定FCJ2为芽孢杆菌属枯草芽孢杆菌Bacillus subtilis。
245 strains of bacteria were isolated from samples of melon rhizosphere soil, yak feces and vermicompost, and 14 strains which had good inhibitory effects on Fusarium oxysporum were screened by plate confrontation method. The strains were determined by tube-plate method and concave-slide method Antagonistic effect of bacterial fermentation broth on melon blight and inhibition of spore germination of powdery mildew of Melon and Melon downy mildew. The results of antibacterial test showed that the inhibitory rate of strain FCJ2 on Fusarium oxysporum f. Sp. Was 64.7% and that on spore germination of powdery mildew and melon downy mildew was 62.3% and 49.2% respectively. The results of pot experiment showed that the control effects of FCJ2 on melon blight, melon powdery mildew and melon downy mildew were 88.5%, 93.6% and 82.6%, respectively, which were significantly different from those of the control group (P <0.05). Identification of morphological characteristics, identification of physiological and biochemical characteristics and 16S rDNA sequence analysis identified FCJ2 as Bacillus subtilis Bacillus subtilis.