我国农田土壤磷素转化的关键微生物组及其解磷机制的研究

Low use efficiency of phosphorus (P) fertilizer in agro-ecosystems is an important issue for Chinese agricultural sustainable development. Increasing P use efficiency via the regulation of P transformation processes by microorganisms is a profound way to ensure food security in the future. This study aims to investigate the P transformation processes and the community composition and functional genes of P-solubilizing microorganisms, based on large-scale sampling in typical agricultural fields in China. We will use advanced techniques such as metagenomics to analyze the ecological distribution pattern of P transformation microorganisms and relevant functional genes; explain the regulation mechanisms of P transformation processes by P-solubilizing microorganisms/genes, and explore the key regulating genes; identify the responses of P-solubilizing microorganisms/genes to soil basic properties and agricultural management practices and build a theoretical model of P transformation processes that affected by these two factors. This study will provide a theoretical support for the sustainable development of P management in order to increase P use efficiency by crops in Chinese agro-ecosystems.

作物磷肥利用率低是我国农业可持续发展面临的主要问题，通过调控土壤磷素转化微生物过程提高磷素利用率是保障未来粮食安全的重要手段。本研究基于大尺度农田土壤样品的采集，利用基因组学技术探讨我国典型农田土壤磷素转化微生物和相关功能基因的生态分布规律；阐明磷素转化微生物和功能基因对土壤磷素形态转化过程尤其是解磷过程的调控机制，寻找关键调控基因；搞清土壤理化性质和农业管理措施两大因素对土壤磷素转化微生物和功能基因的影响机制，建立一个受土壤性质和农业管理措施综合影响的磷素转化微生物过程的理论模型，为解决我国土壤磷素利用率低的现状和农业磷素管理的可持续发展提供理论依据。

本研究基于大尺度典型农田土壤样品的采集结合室内培养盆栽实验，利用基因组学技术探讨了我国典型农田土壤磷素转化微生物和相关功能基因的生态分布规律，阐明了磷素转化微生物和功能基因对无机磷增溶、有机磷矿化和微生物同化三大磷素转化过程的调控机制；明确了土壤pH、化学计量比在不同施肥方式（有机肥和无机肥）下对土壤磷素转化微生物和功能基因的影响机制，建立了受土壤性质和农业管理措施综合影响的磷素转化微生物过程理论模型，为充分解决我国土壤磷素利用率低的问题提供了理论研究基础，已充分完成项目作物养分高效利用的研究目标。目前已经发表SCI论文6篇，其中第一标注4篇。