中文摘要：

以马铃薯坏疽病菌为靶标菌株,采用含药平板法对高寒草地禾草内生细菌B-401产抑菌物质条件及抑菌物质的稳定性进行了研究。结果表明,生防菌株B-401产抑菌物质的最佳培养基配方为牛肉膏8 g、酵母浸膏5.0 g、葡萄糖10 g、水1000 mL,最适温度为23.4℃,最适pH值为7,最佳装液量为35.2 mL/150 mL三角瓶,最佳培养方式为光照条件下振荡培养24 h,最适发酵时间为96 h,优化验证试验结果表明,其对马铃薯坏疽病菌的EC_（50）=0.111μL/mL,是优化前EC_（50）=3.196μL/mL的3.47%。菌株B-401所产抑菌物质在25～90℃具有较好稳定性,抑菌活性均大于75%,在100℃及以上高温处理后抑菌物质活性降低;对酸碱性和紫外照射稳定,相对活性分别在77.45%和98%以上;对金属离子Na＋、Mg2＋和Mn2＋稳定,相对活性达99%以上,而对Ag＋、Cu2＋、Zn2＋和Fe3＋较不稳定。

英文摘要：

Using Phomafoveata as target pathogen, we studied the optimum culture conditions and stabilities of inhibitive substances secreted by antagonistic endophytic bacteria B-401 from alpine meadow pasture. The results showed that the optimal medium of antagonistic substances produced by B-401 was D broth （beef extract 8 g, yeast extract 5.0 g, glucose l0 g, water 1000 mL）, the optimum culture conditions were temperature 23.4℃, pH 7, loading volume 35.2 mL/150 mL flask, the way of cultivation was shaking culture under 24 h illumination, the optimum fermentation time was 96 h. The antifungal substances secreted by B-401 were stable at 25--90 ℃, and the antifungal activities were all surpassed over 75%, and it was reduced after treatment at 100℃ or more. Also the relative activities were resistant to the metal ions Na＋, Mg2＋ and Mn2＋, and become less stable to Ag＋, Cu2＋, Zn2＋, Fe3＋.