《植物生理学报》 2015, 51(5): 601-609

植物对维管束病原菌的防卫反应机制研究进展

张明菊¹, 王红梅², 王书珍¹, 范佩¹, 夏启中^1,*

¹黄冈师范学院生命科学学院, 湖北黄冈438000; ²中国农业科学院棉花研究所, 河南安阳455000

通信作者：夏启中；E-mail: swxqz@hgnu.edu.cn；Tel: 0713-8833119

摘　要：

维管束病害是发生在作物和多年生木本植物上最严重的植物病害类型之一。植物维管束病害通常由土传细菌、真菌和卵生菌侵染根木质部, 在木质部中繁殖, 阻碍水分和矿物质的运转, 使叶片萎蔫和死亡, 导致整株植物受损而最终死亡。对维管束病原物的生物学特性和植物抗病反应的分子机制进行深入了解并设计新的策略来控制维管束病害具有重要的理论和实际应用价值。本文系统地讨论了植物通过两类受体感知维管束病原菌、传递胞内信号、诱发寄主植物对维管束病菌的防卫反应。寄主植物对维管束病原菌物理防卫反应主要包括在木质部小室中形成甲基纤维素(tyloses)和维管束衣被(vascular coating)两个方面, 从而阻止病原菌扩散。寄主植物对维管束病原菌的化学防卫反应主要是指木质部薄壁细胞的急剧代谢变化, 导致木质部液体中不同蛋白质和次生代谢物的积累, 从而杀死或抑制病原菌生长。化学防卫反应在木质部防卫反应中起主要作用。

关键词：维管束病原菌; 木质部; 受体; 防卫反应

收稿：2015-01-14   修定：2015-03-31

资助：国家支撑计划(2011BAD35B05)、湖北省自然科学基金重点项目(2012FFA066)、湖北省自然科学基金一般项目(2008CDB091)和湖北省教育厅重点项目(D20082701和D20102903)。

Research on the Mechanism of Plant Defense Against Vascular Pathogens

ZHANG Ming-Ju¹, WANG Hong-Mei², WANG Shu-Zhen¹, FAN Pei¹, XIA Qi-Zhong^1,*

¹Life Science Department, Huanggang Normal University, Huanggang, Hubei 438000, China; ² Cotton Research Institute, Chinese Academy of Agricultural Science, Anyang, Henan 455000, China

Corresponding author: XIA Qi-Zhong; E-mail: swxqz@hgnu.edu.cn; Tel: 0713-8833119

Abstract:

Vascular wilts are among the most destructive plant diseases that occur in annual crops and woody perennials. The vascular diseases are generally caused by soil-borne bacteria, fungi, and oomycetes. These pathogens can infect the plants through the roots and enter the water-conducting xylem vessels where they proliferate and obstruct the transportation of water and minerals. As a result, leaves become wilt, and the whole plant eventually dies due to the impairment of vascular pathogens. An in-depth understanding of the biological characteristics of vascular pathogens and the molecular mechanism of plant defense response against pathogens so as to design novel effective control trategy is theoretically and practically important. In this review, we discuss the current advance on perception of vascular wilt pathogens by extracellular and intracellular receptor of host plant, intracellular signal transduction and the induction of defense responses against the vascular pathogens. Typical physical defense responses observed during xylem colonization are the formation of tyloses and vascular wall coating around the infected xylem vessels that can block the spread of pathogens. The chemical defense response of host plant against vascular wilt pathogens is the accumulation of different proteins and secondary metabolites in the xylem sap which are caused by drastic metabolic changes in xylem parenchyma cells. The chemical compounds accumulated in xylem sap can eliminate vascular wilt pathogens contained by the physical defense responses. Overall, chemical defense responses play major roles in xylem defense.

Key words: vascular wilt pathogens; xylem; receptor; defense response