软腐病菌胁迫下魔芋根系分泌物的鉴定及其对土壤微生物的调节作用

Root exudates are important carrier materials for plant-soil feedback regulation, and are important pathways for plants to respond to external stress, and also play an important role in the regulation of rhizosphere microecological system. Many reports demonstrated that upon attack by pathogen, plants are able to recruit beneficial microorganisms to defense stress. Soft rot disease is one of the most serious hazards in the production of Amorphophallus konjac. To date, however, there is no effective way to control it. Our study group also have did lots of researches on the Amorphophallus konjac germplasm, and also get the high-resistance variety. In the study, we use metabolomics to qualitative study on the chemicals in root exudates of A. muelleri in response to infection by root rot pathogen, revealing the response characteristics of resistant varieties to bacteria soft rot; qualitative study by was soft. The disease resistance of root exudates induced by root rot pathogen, revealing the response characteristics of resistant varieties to bacteria soft rot; with the high-throughput sequencing and GepChip techniques, quantitative analysis these signal substances regulate the soil microorganisms, clarifying the influence of signal substances on soil microbial composition, diversity and function, elaborate the ecological mechanism of resistance of soil microorganisms to soft rot disease mediated by root exudates. We respect to construct the network and functional model of control soft rot disease by the regulation of rhizosphere microecological system. These studies will benefit us to develop new ecological techniques to control root rot disease.

根系分泌物是植物—土壤反馈调节的重要载体物质，是植物响应外界胁迫的重要途径，对根际微生态系统结构与功能的调控有着重要作用。众多研究发现植物在受到病原菌胁迫后可以通过根系分泌物募集有益微生物帮助自身抵御胁迫。软腐病是魔芋生产中最严重的危害之一，目前尚未有切实有效的防治途径。本项目拟在课题组前期已开展的魔芋种质对软腐病菌抗性研究基础上，以获得的软腐病高抗品种珠芽魔芋为研究材料，通过代谢组学定性研究软腐病菌胁迫诱导下魔芋根系分泌物中具有抗病活性的物质，揭示抗病品种对软腐病菌胁迫的响应特征；通过高通量测序和Gepchip基因芯片等分子技术定量研究这些信号物质对土壤微生物的调节作用，阐明信号物质对土壤微生物组成、多样性和功能的影响，以期探明魔芋根系分泌物信号物质介导土壤微生物抗软腐病的生态机制，构建魔芋抗软腐病根际微生态调控网络和功能模式，为生态防治软腐病关键技术的研发提供理论依据。

根系分泌物是植物—土壤反馈调节的重要载体物质，是植物响应外界胁迫的重要途径，对根际微生态系统结构与功能的调控有着重要作用。众多研究发现植物在受到病原菌胁迫后可以通过根系分泌物募集有益微生物帮助自身抵御胁迫。软腐病是魔芋生产中最严重的危害之一，目前尚未有切实有效的防治途径。本项目在课题组前期已开展的魔芋种质对软腐病菌抗性研究基础上，以获得的软腐病高抗品种珠芽魔芋为研究材料，通过代谢组学分离、鉴定出了软腐病菌胁迫诱导下魔芋根系分泌物中具有抗病活性的代谢物；探明了高抗品种珠芽魔芋与感病品种花魔芋相比，当受到病原菌侵染后，其会通过调控根系抗病相关代谢活性物质来改变根际微生物群落的结构，募集更多的有益微生物，从而显著增强了其自身的抗病能力，有效地抵御了病害的伤害，表现出较强的抗病性。. 本研究的顺利开展揭示了当受到病原菌的胁迫，魔芋通过改变根系分泌物抵御病原胁迫的响应机制，通过调控“魔芋－根系分泌物－根际微生物”相互作用来抵御病害的生态抗病机制，为我们合理有效地调控根际生态系统，最大限度地发挥该系统的功能，构建现代农业生态防治软腐病关键技术提供了理论支持。