兰州百合是中国唯一的甜百合，狭域分布、无性繁殖，多年生栽培。但是多年生百合田枯萎病大面积发生，导致连作障碍严重。而有关百合连作田的微生物区系劣化的理论研究存在大量空白。因此本项目拟利用高通量测序技术，深度焦磷酸测序技术(PCR－DGGE)进行土壤宏基因组研究，分析连作田根际土壤微生物群落演替规律，研究11种酚酸类物质（兰州百合根系分泌物）对土壤健康关键微生物群落的调控作用；利用qPCR，HLPC技术研究上述酚酸类物质对致病镰刀菌（枯萎病病原菌）增殖侵染的影响，受酚酸类物质调控的可培养有益细菌对镰刀菌的拮抗作用；最终探明连作田枯萎病严重发生的微生物因子及植物自毒因子，从寄主、土壤、微生物互作角度，在分子水平上，全面揭示百合产区传统高肥、旱作栽培模式下，病原性连作障碍发生的生物化学机理。研究结果可为百合田应用“土壤消毒—微生物菌肥联用技术”治理连作障碍、本田有益微生物菌剂开发提供依据。

Lanzhou Lily (Lilium davidi) is the only sweet edible lily, which is also one kind of local famous perennial cultivated vegetable varieties in Gansu province. It is also a kind of narrow distribute endemic species in China. Its root rot occurred seriously under long-term continuous cropping. In our former research results, the pathogenic Fungi( Fusarium oxysporium ) were identified and 11 phenolic acids of root exudates were tested under the long-term continuous cropping soil. Depend on them, in this program, we are supposed to research the dynamics of the microbial communities of in the rhizosphere replant soil and the effect of the phenolic acids on Fusarium oxysporium and beneficial bacteria by PCR－DGGE and qPCR analysis, as well as the beneficial bacterial antagonism to the Fungi. From these research data, we can get the microbial and chemical mechanism of pathogenic obstacles of Lanzhou Lily mediated by phenolic acids. The results will be useful to help us to get local specific beneficial microorganism and to remediate the continuous Lanzhou Lily cropping field by a combination of soil fumigation and bio-organic fertiliazer application.