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

【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 of plant 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.