干旱下植物根系分泌物及其介导的根际激发效应研究进展

Effects of drought on plant root exudates and associated rhizosphere priming effect: review and prospect

根系分泌物是植物与土壤进行物质能量交换和信息传递的重要媒介,同时也是植物响应外界环境变化的主要形式,在土壤碳库动态中发挥着重要作用。伴随着全球气候变化而频繁发生的极端干旱事件对植物地上地下生长过程都产生了深刻的影响,然而,由于根-土界面交互作用的复杂性,以及根系分泌物收集手段与装置的不完善,人们对干旱条件下根系分泌物及其介导的根际激发效应的响应及机制的认知尚存在较大的局限性。基于此,该文结合国内外生态学领域的研究前沿动态,论述了干旱下植物根系分泌物数量及组分的动态变化,重点阐述了根系分泌物介导的根际激发效应及其机制,在此基础上展望了未来根系分泌物研究中的重点关注方向,以期为未来全球气候变化条件下土壤碳汇的评估提供科学依据。

Root exudates play an important role in soil carbon balance,acting as an important medium for material and energy exchange and information transfer between plant roots and soil,and also the crucial forms for plant response to environmental changes.Frequent extreme drought events accompanied with global climate change have imposed a profound impact on both above-and below-ground plant growth processes.However,significant limitation exists in understanding the responses of root exudates and their mediated rhizosphere priming effect to drought due to the complexity of root-soil interface interactions and the limitation in devices and methods for collecting root exudates.This paper reviews the effects of drought on the quantity and quality of plant root exudates,with emphasis on the rhizosphere priming effect mediated by root exudates under drought stress.The future research focuses on root exudates was also discussed.This study will provide suggestion for soil carbon sink assessment under the future climate change.