维管束木质化调控植物抗青枯病的研究进展

Research progress on the regulation of vascular lignification on defense against bacterial wilt of plants

细菌性青枯病是由青枯劳尔氏菌(Ralstonia solanacearum)(以下简称“青枯菌”)引起的一种典型的维管束病害,发病后严重影响作物产量与品质。选育抗病品种是从根本上解决青枯病危害的最有效措施,而了解植物免疫反应的分子机制是抗病育种的基础。越来越多的研究表明,维管束免疫具有细胞类型特异性。植物识别青枯菌后,通过信号传导诱导维管束细胞壁木质化,形成植物抵御青枯菌扩散的主要屏障。木质素的合成受到精细的调控,其关键合成酶基因在转录、翻译、时空特异性表达等不同方面受到调控。本文综述了植物对青枯菌的识别和信号传导机制,以及诱导维管束木质化调控青枯病抗性的研究进展,包括诱导木质素合成基因表达、木质素单体转运和聚合、不同木质素类型产生等分子机制,以期为利用维管束木质化改性技术进行青枯病的抗性育种提供理论依据。

Bacterial wilt,a typical vascular disease caused by Ralstonia solanacearum,is one of the most devastating diseases and dramatically reduces crop yield and quality.The most effective strategy for controlling wilt disease is breeding disease-resistant varieties,which requires understanding the molecular mechanisms underlying plant immune responses against R.solanacearum.However,more and more evidence suggests that vascular immune responses are cell type specific.After sensing of R.solanacearum,the cell wall lignification of vascular tissues plays a vital role in restricting the spread of R.solanacearum.Lignin biosynthesis pathway genes are strictly controlled at the transcriptional,translational,and spatial-temporal specific expression aspects.Here,we summarized the current understanding of the recognition and signal transduction upon R.solanacearum infection and the research progress of pathogen-induced vascular lignification on regulating resistance to R.solanacearum,including the expression of lignin biosynthesis genes,the transport and polymerization of monolignols,and the generation of different types of lignin.We hope that this review will provide a theoretical basis for breeding bacterial wilt disease-resistant cultivars by modifying vascular lignification.