根系分泌物收集技术研究进展

Research progress of root exudates collection technology

根系分泌物在调控陆地生态系统根际微环境间的物质、能量和信息交流中具有重要作用.构建准确、适用的根系分泌物收集方法,对根系分泌物的种类、含量及其对环境变化的响应等信息的精准获取是理解植物根系-土壤界面生态过程与信息交流的关键环节和前提.目前,传统或新型的根系分泌物收集技术都致力于认知根系分泌物中化合物种类多样性和含量变化,但根系的生长高度依赖周围介质和生长环境,使根系分泌物的收集很难避开对根系本身的损伤、土壤颗粒对根系分泌物的吸附和释放,以及微生物代谢等因素的干扰,导致不同根系分泌物收集方法都存在各自的优缺点.本研究从室内收集和野外原位收集两方面系统综述了当前应用较广的一些传统和新型根系分泌物收集技术,并总结和比较了每种收集方法的优缺点;在此基础上,基于森林根际生态学过程野外原位研究的重要性和代表性,结合当前根系分泌物研究的不足,展望了未来森林根系分泌物野外原位收集技术构建中值得关注的3个重点方向,旨在为相关研究者开展根系分泌物收集与作用研究提供参考.

Root exudates play an important role in mediating the exchange of substrates, energy and information within the rhizosphere in terrestrial ecosystems. Constructing accurate and applicable sampling system of root exudates to precisely collect the characters including the component and concentration of root exudates and their responses to changing environments are a critical link and prerequisite to understand ecological processes and information exchanges across the root-soil interface. While both traditional and novel techniques for collecting root exudates aim to explore the diversity and concentration of root exudates, current exudate-collection methods could hardly avoid the damage of root system, the adsorption and release of root exudates by soil particles, and distur-bance from microbial metabolism, largely because plant roots are highly associated with the surrounding substrates and environments supporting their growth. Therefore, all root exudate collection methods have their own merits and shortcomings. We systematically reviewed the widely-used traditional and novel root exudates collection techniques and compared their advantages and disadvantages. Furthermore, considering the significance and authenticity of field study on the rhizosphere ecological processes in forest ecosystems, we proposed three frontier research directions regarding the construction of techniques for collecting root exudates in forest ecosystems according to the limits of current studies, aiming to provide foundation for related studies in the future.