丛枝菌根网络介导的植物间信号交流研究进展及展望

丛枝菌根(arbuscularmycorrhizal,AM)真菌是一类能够与绝大多数陆地植物形成共生关系的土壤真菌,其根外菌丝可以侵染不同植物根系且可以进行菌丝融合,从而形成丛枝菌根网络(arbuscular mycorrhizal networks, AMNs)。AMNs可以在植物之间转运水分及营养元素如碳(C)、氮(N)、磷(P)等,最近研究表明AMNs还可以在植物遭受环境胁迫时向邻近植物传递防御信号,对周围植物起到“预警”作用。目前,关于环境胁迫条件下AMNs介导的信号物质传递研究仍处于起步阶段,许多问题亟待回答。该文首先回顾了目前有关AMNs介导的信号物质传递研究进展,继而梳理了这一研究领域值得进一步探究的科学问题,包括AMNs在植物间传递防御信号的可能途径及相关机制, AMNs介导的信号传递对菌根共生体系的可能影响,以及AMNs研究中常用的技术及其发展,最后讨论了AMNs介导的信号物质传递在作物保护等方面的可能应用。

Research progress and prospect of signal transfer among plants mediated by arbuscular mycorrhizal networks

Arbuscular mycorrhizal (AM) fungi are a group of soil-dwelling fungi that can form symbiotic associations with most terrestrial plants. The extraradical mycelium can colonize different plant roots in addition to hyphal fusion, thus form extensive arbuscular mycorrhizal networks (AMNs) underground. AMNs can transport and recycle water and nutrients including carbon, nitrogen, phosphorus among plants, recent evidences show that AMNs can also transfer defensive signals to neighboring plants when plants suffer environmental stresses, thus providing early warning to surrounding neighbors. However, the research on AMNs-mediated signal transfer is still in its infancy. Here, we firstly reviewed current research progresses in this research area, then proposed the unanswered questions that worth exploration in the future, including the possible pathways and mechanisms of signal transfer via AMNs among plants, the possible regulation of mycorrhizal symbionts by AMNs-mediated signal transfer, and the common techniques and their development used in the study of AMNs. Finally, we discussed about the possible ecological applications of AMNs such as filed crop protection.