Ahn Il-Pyung, Lee Sang-Woo, Suh Seok-Cheol
National Institute of Agricultural Biotechnology, Rural Development Administration, Suwon 441-100, Korea.
Mol Plant Microbe Interact. 2007 Jul;20(7):759-68. doi: 10.1094/MPMI-20-7-0759.
A nonpathogenic rhizobacterium, Pseudomonas putida LSW17S, elicited systemic protection against Fusarium wilt and pith necrosis caused by Fusarium oxysporum f. sp. lycopersici and P. corrugata in tomato (Lycopersicon esculentum L.). LSW17S also confers disease resistance against P. syringae pv. tomato DC3000 (DC3000) on Arabidopsis ecotype Col-0. To investigate mechanisms underlying disease protection, expression patterns of defense-related genes PR1, PR2, PR5, and PDF1.2 and cellular defense responses such as hydrogen peroxide accumulation and callose deposition were investigated. LSW17S treatment exhibited the typical phenomena of priming. Strong and faster transcription of defense-related genes was induced and hydrogen peroxide or callose were accumulated in Arabidopsis treated with LSW17S and infected with DC3000. In contrast, individual actions of LSW17S and DC3000 did not elicit rapid molecular and cellular defense responses. Priming by LSW17S was translocated systemically and retained for more than 10 days. Treatment with LSW17S reduced pathogen proliferation in Arabidopsis ecotype Col-0 expressing bacterial NahG; however, npr1, etr1, and jar1 mutations impaired inhibition of pathogen growth. Cellular and molecular priming responses support these results. In sum, LSW17S primes Arabidopsis for NPR1-, ethylene-, and jasmonic acid-dependent disease resistance, and efficient molecular and cellular defense responses.
一种非致病性根际细菌，恶臭假单胞菌LSW17S，可诱导番茄（番茄属）对尖孢镰刀菌番茄专化型引起的枯萎病和髓坏死以及皱纹假单胞菌产生系统保护作用。LSW17S还赋予拟南芥生态型Col-0对丁香假单胞菌番茄致病变种DC3000（DC3000）的抗病性。为了研究疾病保护的潜在机制，研究了防御相关基因PR1、PR2、PR5和PDF1.2的表达模式以及过氧化氢积累和胼胝质沉积等细胞防御反应。LSW17S处理表现出典型的引发现象。在经LSW17S处理并感染DC3000的拟南芥中，诱导了防御相关基因的强烈且更快的转录，并且积累了过氧化氢或胼胝质。相比之下，LSW17S和DC3000的单独作用并未引发快速的分子和细胞防御反应。LSW17S引发作用可系统地转移并持续超过10天。用LSW17S处理可减少在表达细菌NahG的拟南芥生态型Col-0中的病原体增殖；然而，npr1、etr1和jar1突变削弱了对病原体生长的抑制。细胞和分子引发反应支持这些结果。总之，LSW17S使拟南芥对依赖NPR1、乙烯和茉莉酸的抗病性以及有效的分子和细胞防御反应产生引发作用。
