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期 刊 ：植物保护学报 2010年

关键词：拮抗；枯草芽孢杆菌；生物防治；甜瓜；16S rDNA；

Keywords:antagonist, Bacillus subtilis, biocontrol, muskmelon, 16S rDNA,

摘 要 ：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。

Abstract:Using the plate confrontation assay, fourteen strains with antagonistic effect on the pathogens of Fusarium oxysporum f.sp.melonis were screened out of 245 bacteria isolated from rhizosphere soil, yak dung and vermicompost. The inhibition rates of antagonistic fermentation broth to F.oxysporum, Sphaerotheca cucurbitae, and Pseudoperonospora cubensin were tested using agar diffusion method and concave slide test method. The results showed that the inhibition rate of strain FCJ2 fermentation broth was 64.7% to F.oxysporum, and spore germination inhibition rate were 62.3% to S.cucurbitae and 49.2% to P.cubensin, respectively. The strain FCJ2 had significant control efficacy (P<0.05) when compared with the pesticides treatments, with 88.5% control efficacy on F.oxysporum, 93.6% on S.cucurbitae, and 82.6% on P.cubensin, respectively. According to morphologic, physiological, biochemical characteristics and 16S rRNA sequence analysis, strain FCJ2 was classified as Bacillus subtilis.

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