Studies on promoting tomato growth and controlling early blight using Bacillus subtilis QM3 | 枯草芽胞杆菌QM3防治番茄早疫病和促进幼苗生长的研究

Chinese. 摘　　要：［目的］ 枯草芽胞杆菌QM3是从青海牦牛粪中分离筛选的一株对番茄早疫病菌有显著抑菌效果的高效拮抗菌株，本文旨在进一步明确QM3对番茄早疫病的作用机制和在生物体内的防治效果。 ［方法］ 采用温室盆栽试验测定QM3发酵液对番茄早疫病的防治效果及对不同番茄品种的促生作用，并测定该菌株在番茄根际的定殖能力。［结果］ 不同处理的QM3发酵液均对番茄早疫病有明显的防治效果（p〈0.05），最高可达52.94%，且与化学农药联合使用防效更好，最高可达71.80%；经QM3发酵液处理后，番茄植株叶片数、株高及根部发育等指标有增加；此外，灌根接种QM3菌株后，根际总芽胞杆菌数量明显增加（p〈0.01）。［结论］ QM3菌株是一株有益的促生根际细菌（PGPR），具有应用于番茄早疫病生防的潜力。

English. [Objective]Bacillus subtilis QM3, isolated from dung of Qinghai yaks, was a highly efficient antifungal strain against Alternaria solani. This study aimed to understand its antagonistic mechanism and control effect on A. solani in vivo. [Method] The method of pot cultivation in greenhouses was employed in order to verify disease prevention in vivo and promote health and colonization ability of the strain QM3. [Result] The fermented broth of QM3 could significantly control tomato early blight （p〈0.05）, and its control efficacy was up to 52.94%. By jointly using chemical pesticides, a better control effect （p〈0.05） was obtained. The highest control efficacy was 71.80%. QM3 broth also had a significant growth promoting role on tomato, with leaves, plant heights and root development as the main indicators. In addition, the number of B. subtili_s around tomato plants increased significantly （p〈0.01） after treated with QM3. [Conclusion] These results revealed that the strain QM3 is a useful plant growth_promoting rhizobacteria （PGPR）, with a potential biocontrol application to A. solani in the future.