基因标记枯草芽孢杆菌BS-68A在黄瓜上定殖

Colonization of A Gene-marked Bacillus subtilis BS-68A in Cucumber

目的:野生型枯草芽孢杆菌Bacillus subtilisBS-68能有效地防治由Pythium spp.和Fusarium oxporum引起的黄瓜立枯病和枯萎病。为了探究该菌株的生防机制,利用该菌株的黄绿荧光蛋白基因和氯霉素抗性基因标记菌株BS-68A研究其在黄瓜植株各个部位的定殖能力、种群动态和在根围的分布。方法和结果:用基因标记菌株发酵液分别对黄瓜种子进行浸种和浇穴处理,播种后30d,该菌能在黄瓜根部和茎基部定殖,不能在茎部和叶部定殖。浸种处理,该菌在茎基部的种群数量为3.1×104cfu/株,大于根部的种群数量4.1×102cfu/株;浇穴处理,该菌在茎基部的种群数量8.0×103cfu/株,低于根部的种群数量2.5×104cfu/株。

Objective：Wild Bacillus subtilis strain BS-68 is effective to control cucumber root rot disease caused by Pythium spp.and Fusarium oxporum. A gene- marked strain BS- 68A was used to study the colonization ability,fluctuation of population and distribution pattem on rhizosphere of cucumber.Methods and Results： The studies indicated the strain can colonize in the root and stem base of cucumber,but can not colonize in the stem and leaf as a seed and soil treatment.For 30 days after planting,its population in the stem base are more than in the root by soading the seeds. Whereas, its population in the stem base are less than in the root by spraying the soft.