多组学联合解析王草与耐性菌协同修复Cd-Cr复合污染土壤的共调控效应及机制研究

微生物协同植物修复是一项低成本、环保、有效的重金属污染土壤原位治理技术，植物根系和土壤微生物之间的相互作用对于植物修复工作至关重要。前人研究多集中于植物修复重金属污染土壤效应的研究，而忽略了根系分泌物调控及功能微生物与分泌物协同调控重金属有效性的研究。本试验以适宜海南的Cd/Cr富集植物王草与耐重金属的土著优势菌联合体系为研究对象，结合高通量组学、转录组学、代谢组学等多组学技术手段的应用，通过培养、根箱和盆栽试验，挖掘矿区周边污染土壤中耐性菌种资源，探索重金属复合污染土壤中耐性菌对王草根系分泌物组成特性的影响，揭示关键根系分泌物与重金属有效性的互馈关系；明晰根际化学与生物过程中关键根系分泌物的代谢途径及其相关基因表达和蛋白质功能，阐明王草根系与耐性菌协同调控Cd和Cr有效性的耦合机制，为富集植物通过根际调控提高修复效率提供理论指导和科学依据。

Microbial-assisted phytoremediation is a low-cost, environmentally friendly and effective technique for in-situ remediation of heavy metals-contaminated soils, and the interaction between plant roots and soil microorganisms is crucial to phytoremediation efforts. More studies have shown that plant development affects the composition of the soil microbiota and its functions, but relatively few studies have understood the secretion characteristics of plants and the uptake characteristics of microbial substrates and their metabolic pathways. The aim of this project is to formulate a novel phytoremediation strategy by using Hainan's local metals-accumulating plants-king grass (Pennisetum Americanum × P. purpureum) coupled with soils metal-resistant microbes. A series of root box experiment, pot experiment and microcosm incubation based on the multi-omics techniques such as high-throughput histology, transcriptomics and metabolomics will be employed to determine: 1) to exploit the tolerant microbes in the soil around the mining area, 2) to investigate the constituents and differences of the root exudates of king grass under different treatment conditions in Cd-Cr complex contaminated soils, 3) to clarify the metabolic pathways of the root exudates which play a major role in enriching for Cd-Cr, and metabolite-related gene expression and protein function; 4) to elucidate the regulatory relationships between Cd/Cr availability and king grass synergistically with resistant bacterium. Furthmore, this study will provide the scientific evidence of improve phytoextraction efficiency by rhizosphere regulation.