摘要
樟树内生枯草芽胞杆菌EBS05是一株对多种植物病原菌具有较强拮抗活性，并能诱导烟草系统抗性的生防菌株。本文以缺失SurfactinA合成相关基因的突变菌株EBS05^T为材料，研究了内生细菌EBS05对烟草诱导系统抗性的激发子及其信号转导途径。结果表明，菌株EBS05产生的SurfactinA是诱导烟草对TMV系统抗性的有效激发子；SurfactinA诱导处理后，SA信号转导途径下游的关键调节基因NPR1首先被激活，并持续超量表达，进而触发PR1b和PR1a基因持续超量表达，表明SurfactinA诱导烟草对TMV的系统抗性是通过激活SA信号转导途径实现的。同时，SttrfactinA诱导处理后24～72h，JA／ET信号转导途径调节基因PDF1．2被激活，且超量表达，表明在SurfactinA诱导烟草对TMV系统抗性的信号转导过程中，可能存在SA信号途径和JA／ET信号途径的交叉协同作用。
Bacillus subtilis EBS05, an endophytic bacteria strain isolated from Cinnamomum camphor, has strongly antibiotic activity to various plant pathogen and elicitation of induced systemic resistance （ISR） as well. The ISR elicitor and signal transduction pathway in tobacco plants were investigated by reverse transcription PCR （RT-PCR） and Real-time PCR techniques with the mutant strain EBS05T（ knockout surfactin A synthetic gene） as experimental material. The results showed that Surfactin A produced by endophytic bacteria EBS05 played a major role as the efficient elicitor in EBS05-induced systemic resistance against Tobacco mosaic virus. After treated with Surfactin A, the key regulatory gene NPR1 located in the downstream of SA-signalling transduction pathway was firstly activated and overexpressed constantly, and then resulted in overexpression of gene PRlb and PRla, in dicating that ISR triggered by Surfactin A in tobacco plants depended on SA-signalling transduction pathway. Moreover, gene PDF1.2, as a regulatory gene in JA/ET-signalling transduction pathway, was elicited and overexpressed from 24 hours to 72 hours after treated with Surfactin A. It suggested that cross-talk between SA- and JA/ET-dependent signalling pathways might be involved in ISR mediated by strain EBS05 in tobacco plants defense responses against Tobacco mosaic virus.
出处
《植物病理学报》
CAS
CSCD
北大核心
2014年第5期527-535,共9页
Acta Phytopathologica Sinica
基金
国家自然科学基金资助项目(31272083)
关键词
植物内生细菌
系统诱导抗性
信号转导
烟草花叶病毒
plant endophytic bacteria
induced systemic resistance
signal transduction
Tobacco mosaic virus
