Biocontrol effection of genetically-modified strains derived from bacillus subtilis 168 on meloidogyne incognita | 枯草芽胞杆菌168的遗传修饰菌株对番茄根结线虫病的生防作用

chinois. PopW 是来源于青枯病菌(Ralstonia solancearum)的一种harpin 蛋白，具有诱导植物抗病性和促进植物生长的作用。构建了含有 p43 强启动子和 nprB 信号肽的PopW基因的表达载体 pHTPOW，将表达载体 pHTPOW转入枯草芽胞杆菌(Bacillus subtilis)168得到工程菌株BsW。SDS-PAGE 和 Western blot 结果表明 BsW 能分泌 PopW 蛋白。在离体实验中，测试工程菌 BsW 对南方根结线虫(Meloidogyne incognita)二龄幼虫(J2)的致死作用，结果显示处理24和48 h后，J2 死亡率分别为53.4%和79.6%；在温室实验中，施用工程菌 BsW的菌悬液处理番茄(Lycopersicon esculentum)植株，6 周后根系上的卵块和根结数目明显减少，防效达到60.0%。具有促生和抑制线虫作用基因工程菌的构建，为研究和开发新型微生物农药，提供了一个新的视角。

anglais. PopW from Ralstonia solanacearum is a member of the harpin protein family, eliciting hypersensitive cell death in non-host plants, inducing disease resistance in plants and enhancing plant growth. To achieve secretory expression of PopW protein in Bacillus subtilis, we constructed recombinant expression vector pHTPOW, which carried the p43 promoter, a signal peptide element of nprB, and the full length PopW gene. The expression of PopW in the genetically modified strains was confirmed by SDS-PAGE and Western bloting analysis. In vitro test showed that on the 24 and 48 h after treated with the genetically modified strain BsW, the J2 mortality rates of Meloidogyne incognita were 53.4% and 79.6%, respectively. In the green house trials, the number of eggs and galls reduced significantly 42-days after tomato (Lycopersicon esculentum) treatment with the transgenic strain BsW and the biocontrol efficacy reached 60.0%. The genetically-modified bacteria strain, which enhances plant growth and inhibits nematodes activity, offers a new promising perspective on the reasearch and development of new microbial pesticides.