植物根际沉积与土壤微生物关系研究进展

Advances in the study of the relationship between plant rhizodeposition and soil microorganism

【目的】活跃的根际微生物被喻为植物的第二套基因组,在植物的生长发育过程中发挥着关键作用。植物通过根际碳沉积影响根际土壤微生物群落的结构和功能;作为根际微生态系统中的物质流、能量流和信息流,根际碳沉积是连接大气、植物和土壤系统物质循环的重要纽带;因此,理解根际碳沉积在根际微生态中的作用对于提高植物抗逆性,增加作物产量,调控根际养分循环等方面具有重大的理论意义。【主要进展】本文就近年来关于根际微生物领域的研究成果,重点综述了根际微生物多样性和组学研究;根际碳沉积的组成和产生机理;根际微生物群落结构的形成机制;根际微生物在促进作物养分吸收、提高作物抗逆性等方面的生态功能;以及气候变化和长期施肥对植物-微生物互作关系的影响。在此基础上我们提出了未来可能的研究重点和发展方向:1)植物根际沉积物原位收集方法和检测技术的改进和发展;2)稳定同位素探针与分子生态学技术的结合,将植物、土壤和微生物三者有机地联系起来,综合分析根际界面中微生物的活性与功能;3)高通量测序、组学技术和生物信息学等新技术的引入势必使根际微生物学研究发生革命性的变化;4)随着全球气候变化和土壤肥力改变,例如全球变暖、CO2浓度升高和长期施用化肥,根际沉积物在植物-土壤-微生物中的分配与调节机制,以及这种环境选择压力下植物如何诱导根际促生菌发挥更大作用。希望通过平衡作物与微生物之间的相互关系来实现作物的高产高效,促进农田的可持续利用。

[Objectives]The active rhizosphere microbiome, also referred as the second genome of plant, is crucial for plant growth and development. The structure and function of microbial community in the rhizosphere are affected by plant-derived carbon through rhizodeposition, which is considered as the main modality of material flow, energy flow and information flow in plant rhizosphere system, and play a role of interconnects in the air-plant-soil system. Hence, understanding the function of rhizodeposition is of theoretically meaning to study to plant stress tolerance improvement, crop yield increase and nutrient cycling regulation in the rhizosphere soil. [Main advances] In this paper, the latest results and trends of the rhizosphere microbiome research were reviewed, especially focused on 1） rhizosphere microbial diversity and omics research, 2）components and generation mechanism of rhizodeposition, 3） formation mechanism of microbial community structure in the rhizosphere, 4）the ecological functions of rhizosphere microbiome in enhancing nutrient uptake and plant stress tolerance, and 5 ） the influences of climate change and long-term fertilization on plant-microbe interaction. On this basis, the future research and development direction were discussed：1 ） Improvement and development of the in-situ collection method and measurement technique ofplant rhizodeposits. 2 ） The combination of the stable isotope probing （ SIP ） and molecular ecology techniques to plant, soil and microorganism could be used to analyze the functions and roles of rhizosphere microbiome. 3） The applications of new technologies （ e. g. next-generation sequencing technologies, ‘omics ’ technologies and bioinformatics tools） might revolutionize the development of rhizosphere microbiome research. 4 ） With the changes in global climate and soil fertility, such as global warming, elevated atmospheric CO2 concentration and long-term inorganic fertilization, environmental factors will play a more important role on the regulation mechanism of root-derived carbon in the plant-soil-microorganism system, and the inductive effect of plant under such specific environment on plant growth promoting rhizobacteria（PGPR）. These knowledge will provide a view on how to establish a sustainable soil-crop system with high productivity and high efficiency through coordinating the interaction between crop and rhizosphere microbiome.