[目的]本文探究了枯草芽孢杆菌对白粉病病的抑制作用及其防治效果.[方法]采用扫描电子显微镜(SEM)观察枯草芽孢杆菌对白粉菌菌丝的抑制作用,同时结合田间及烘烤对比实验测定烟草生长期和烘烤过程中枯草芽孢杆菌对白粉病的防控效果.[结果]枯草芽孢杆菌对白粉菌菌丝生长和分生孢子萌发均有明显的抑制作用,其能使白粉菌菌丝顶端肿胀变形呈球状,导致新生分生孢子的个数显著减少;田间实验显示,枯草芽孢杆菌对烟草白粉病的田间防效可达70％以上,与化学药剂甲基硫菌灵相当,且对烟草叶片有一定的促生作用;烘烤前在发病烟叶上喷施枯草芽孢杆菌,可有效降低烘烤过程中白粉病的发病程度,其防效为36.59％,而甲基硫菌灵则不具备这种作用.[结论]枯草芽孢杆菌不仅对田间防治白粉病具有重要应用价值,而且在烘烤过程中也能降低白粉病原菌的再侵染,其控病作用的机制可能是对病原菌孢子萌发具有一定的抑制作用.%[Objective] In this paper,the inhibition and control efficacy of Bacillus subtilis against powdery mildew were explored.[Method] The inhibition of Bacillus subtilis to powdery mildew hyphae by scanning electron microscope (SEM) was observed,combined with contrast test in the field and curing,the damaging effects of Bacillus subtilis on powdery mildew during tobacco growth and curing were determined.[Result] Bacillus subtilis significantly exhibited inhibitory effect on the growth of powdery mildew hypha and its conidium germination,causing the top of the powdery mildew hyphae deformation and became swelling and spherical and leading to the significant reduce of new born identify spores.Further study displayed that the control effect of Bacillus subtilis on tobacco powdery mildew in the field was more than 70 ％,similar to Thiophanate-methyl,and the growth of tobacco leaves was promoted.It was effective to reduce the occurrence of powdery mildew spraying Bacillus subtilis on tobacco leaf before curing,the control effect was up to 36.59 ％.However,thiophanate-methyl did not exhibited this effect.[Conclusion] The results indicated that Bacillus subtilis not only had important application value for prevention and control of powdery mildew in the field,but also could reduce the infection of powdery mildew.The inhibitory on spore germination may be the main disease control mechanism.
展开▼
