Abstract

Ralstonia solanacearum, the causing agent of crop bacterial wilt, is a devastating bacterium with an unusually wide host range. To effectively integrate durable resistance to R. solanacearum into crops, comprehensive and global information on pathogenesis mechanisms employed by this pathogen is important. In this study, we report the development of an efficient Arabidopsis-based bioassay system useful for screening of large number of bacterium mutants with altered virulence. The effectiveness and uniqueness of this system was further demonstrated by the isolation of R. solanacearum mutants exhibiting differential pathogenesis and in vitro characteristics, and by the identification of mutants with the transposon inserted in known and novel loci. This highly efficient bioassay system, together with the accompanying in planta and in vitro bioassay systems described here, would facilitate comprehensive study on R. solanacearum pathogenesis mechanisms.

中文摘要

由青枯病菌(Ralstonia solanacearum)所引起之細菌性萎凋病會導致眾多重要作物的嚴重損失，為整體性地考量有效且持久的病害防治措施，全面性瞭解青枯病菌的致病機制當然十分重要。本研究中，我們研發以阿拉伯芥為基礎的生物測試平台，可快速且有效大量篩選病原性改變之病菌菌株。我們已成功地運用此系統篩選出致病力及多種特性各異的青枯病菌突變株，並更發現這其中包含了在已知或新穎的病原性相關基因被破壞的突變株，進一步驗證並支持這個系統的有效性與獨特性。藉由此高效率之生物檢定平台，並配合本研究所使用的多種宿主植物內及宿主體外分析系統，將極利於進行深入且全面性的青枯病菌致病機制研究。

Keyword: Ralstonia solanacearum, mutant, screening, Arabidopsis. 青枯病菌、突變株、篩選、阿拉伯芥。