稻草腐解菌剂JN01调控土壤硝化和反硝化的微生物机制研究.

Straw returning is an effective way to resolve the environmental problems of straw , realize the resources recycling and agricultural sustainable development.Simple straw- returning is detrimental to the growth of crop becauses of nitrogen nutrient hold. Decomposing Agent JN01 was a set of composite microbial system which can promote straw decomposing, eliminate adverse effect, increase rice yield. Our previous studies showed that the Decomposing Agent JN01 could accelerated straw decay quickly and increase rice yield by changing the soil nitrification and denitrification bacteria community structure and raising rice nitrogen utilization. But the mechanism of Decomposing Agent JN01 regulate soil nitrification and denitrification is unclear.In this study, the typical soil in jiangxi province as the research object and the soil biology, high-throughput sequencing and q PCR technology were used to research the effects of Decomposing Agent JN01 on soil microbial community structure and function genetic diversity and abundance, the transcriptome technology was used to research Decomposing Agent JN01 regulate the transcription process of functional genes of nitrification and denitrification , Reveals the mechanism of Decomposing Agent JN01 regulate soil nitrification and denitrification. Enriches and perfects the earth biochemical process of nitrogen, Provide a scientific reference for the promotion of straw-returning.

稻草还田是解决稻草产生的环境问题、实现资源循环利用和农业可持续发展的有效途径。单纯的稻草还田会造成前期氮素养分固持而不利于下茬作物生长。稻草腐解菌剂JN01是课题组筛选的一组具有促进稻草腐解、增加水稻产量的复合微生物菌系。我们前期的研究表明，该菌剂在加快稻草快速腐解的同时通过改变土壤硝化和反硝化菌的群落结构、提高水稻氮素利用率来促进水稻增产。但稻草腐解菌剂JN01调控土壤硝化和反硝化的内在机制尚不清晰。本项目以江西典型的双季稻田土壤为研究对象，利用土壤生物学、高通量测序和荧光定量PCR等技术研究稻草腐解菌剂JN01对土壤微生物群落结构及其相关功能基因多样性和丰度的影响；应用转录组学策略研究稻草腐解菌剂JN01调控硝化和反硝化相关功能基因转录过程，揭示稻草腐解菌剂JN01调控土壤硝化和反硝化的微生物机制。丰富人们对氮素的地球生物化学过程的认识，为合理推广稻草还田技术提供科学依据。

本项目针对红壤双季稻区稻田土壤在稻草还田配施腐解菌剂JN01后氮素循环机制不清的问题，利用传统分析方法和高通量测序技术结合，对秸秆还田条件下配施腐解菌剂JN01后水稻生育期土壤生物化学性状和水稻农艺性状和产量进行了测定；腐解菌剂JN01对水稻养分积累及产量、土壤化学性状和生物学性状影响。发现稻草腐解菌剂JN01可以提高土壤养分供给能力、促进水稻高产、培肥土壤；提高了土壤中酶活性，尤其是氮素循环相关酶的活性；提高了土壤微生物多样性，尤其是能提高水稻生长有益微生物的丰度；阐明了稻草腐解菌剂JN01对稻田土壤培肥和氮素循环的微生物机制；阐明了稻草腐解菌剂JN01对土壤硝化功能微生物群落之间的耦合关系，为红壤双季稻区稻草还田提供了科学的理论依据。