中文摘要：

2011年在剑湖高原湿地3个入水口，1个出水口和湖面上分别采集茭草根系及对应土样，通过对样品DNA提取和PCR扩增，采用DGGE方法分析及内生细菌16SrDNA片段的克隆和测序，对剑湖茭草根系内生细菌多样性类群及种群影响因子进行研究。结果表明，剑湖不同取样地点的茭草根系内生细菌多样性不同，入水口金龙河的茭草根系内生细菌Shannon指数和Simpson指数最高，而出水口黑惠河的茭草根系内生细菌Shannon指数和Simpson指数最低；聚类分析显示所得细菌DGGE片段序列分为4个类群，分别为Firmicutes、Beta—proteobacteria、Gamma—proteobacteria和Unculturedbacterium；冗余分析显示，NH。’显著影响着茭草根系内生细菌的种群结构。

英文摘要：

Zizania caduciflora roots and soil sample were collected from water inlet, outlet and lake surface of Jian- hu plateau wetland respectively. The diversity and community structure of endophytic bacteria in Z. caduciflora roots were investigated by using denaturing gradient gel electrophoresis （DGGE） and 16S rDNA library methods. The results showed that the diversity of endophytic bacteria was different in each sampling location, the highest Shannon and Simpson index from the inlet-Jinlong River and the lowest from the outlet-Heihui River. The result of cluster analysis indicated that DGGE sequence was divided into four groups, they were Firmicutes, Beta- proteobacteria, Gamma-proteobacteria and Uncultured bacterium respectively. The result of Redundancy analysis （RDA） showed that NH4＋ had an important impact on endophytic bacteria community.