抗烟草青枯病拮抗菌的筛选及抑菌活性研究

目的]为了筛选能有效防治烟草青枯病的生防菌株。方法]对从土壤中分离到的链霉菌产生的次生代谢产物的抑菌活性和理化性质采用管碟法进行了测定。结果]离体条件下,发酵液具有耐热性,在100℃以下仍具有较强的抑菌活性。在一定的pH值范围内(pH值3.8～9.0),拮抗能力无明显差异,其中在接近中性条件下拮抗活性较强。拮抗物质经胰蛋白酶处理后,拮抗活性亦无明显变化。经终浓度为2 mol/L(NH4)2SO4处理过的粗发酵液,其上清液与沉淀均具有拮抗活性,沉淀经SDS-PAGE凝胶电泳检测证明其拮抗物质具有蛋白质性质。结论]1#链霉菌具有很好的开发研究价值。

Study on the Screening and Antagonistic Activity of Antagonists against Tobacco Bacteria Wilt (Ralstonia solanacearum)

Objective] The research aimed to screen bacteria strains against tobacco bacteria wilt.Method] The antagonistic activity and physicochemical properties fermentation products of streptomyces divided from soil were determined with cylinder-plate method.Result] The fermentation products of streptomyces had high antagonistic activity to Ralstonia solanacearum.The extraction had high tolerance to heat and still had strong activity under 100 ℃.There were no significant difference on the antagonistic activity against Ralstonia solanacearum under pH value 3.8-9.0 and treated with trypsin.Both the sediment and super had antagonistic activity after the treatment with the final concentration of 2 mol/L(NH4)2SO4.The sediment had examined by SDS-PAGE electrophoresis and proved that the antagonistic substances had protein nature.Conclusion] 1# streptomyces had good development and research value.