解淀粉芽胞杆菌XJ5挥发性物质抑菌活性及对苹果褐腐病防效测定

Antifungal Activity of Volatile Organic Compounds from Bacillus amyloliquefaciens XJ5 and Control Effect against Monilinia fructigena

解淀粉芽胞杆菌Bacillus amyloliquefaciens XJ5挥发性物质对苹果褐腐病菌Monilinia fructigena等多种病原真菌具有良好的拮抗活性。通过固相微萃取-气相色谱质谱联用仪(Solid-phase microextraction-Gas chromatography mass spectrometry,SPME-GC-MS)对菌株XJ5产生的挥发性物质进行检测,利用平板对扣法测定挥发性化合物的抑菌活性,并离体接种评价菌株XJ5挥发性物质对苹果褐腐病的防效。结果表明,XJ5菌株挥发性物质对9种植物病原真菌的抑菌率在47.9%~84.8%,其中对苹果褐腐病菌的抑菌率最高为84.8%。SPME-GC-MS检测及抑菌活性测定表明,菌株XJ5分泌的主要挥发性物质为十二醛(Dodecanal),具有抑菌活性的挥发性物质主要为2-壬醇(2-Nonanol)、2-乙基己醇(2-Ethyl-1-hexanol)和2-十一醇(2-Undecanol)。其中2-壬醇抑制苹果褐腐病菌的EC50为3.43μg/mL,且XJ5菌液离体熏蒸与2-壬醇离体熏蒸均可有效抑制苹果褐腐病菌丝生长及病斑扩展,其对苹果褐腐病的离体防效分别在14.4%~71.2%和66.4%~97.6%,与对照差异显著。

Volatile organic compounds(VOCs) of Bacillus amyloliquefaciens XJ5 have good antifungal activity against various pathogenic fungi such as Monilinia fructigena.The VOCs produced by strain XJ5 were detected by SPME-GC-MS,their antifungal activities were determined by two-sealed-base-plates method,and the control effects against M.fructigena were evaluated in vitro.The results indicated that inhibition rate of XJ5 VOCs against nine pathogenic fungi were ranged between 47.9% and 84.8%,and the highest inhibition rate against M.fructigena was 84.8%.SPME-GC-MS analysis and antifungal activity determination showed that the major VOCs produced by strain XJ5 were Dodecanal,and the major VOCs with antifungal activity were 2-Nonanol,2-Ethyl-1-hexanol and 2-Undecanol.The EC50 value of 2-Nonanol inhibiting M.fructigena was 3.43 μg/mL.In vitro fumigation with XJ5 bacteria suspension and 2-Nonanol can effectively inhibited the mycelial growth of M.fructigena and the lesion development.The fumigation control efficacies of XJ5 bacteria suspension and 2-Nonanol against M.fructigena were 14.4%~71.2% and 66.4%~97.6%,respectively,significantly different from those of the control.