赣西油茶人工林土壤微生物群落的多样性

Soil microbial community diversity of Camellia oleifera forest in western Jiangxi

为了解油茶林土壤微生物群落结构特征,揭示油茶林土壤微生物群落结构多样性变化特征对林龄和季节等环境因素的响应机制,为油茶林合理经营管理提供理论依据,以赣西地区新余市渝水区不同林龄油茶林24个土壤样品为研究对象,采用变性梯度凝胶电泳（PCR-DGGE）技术分析油茶林土壤细菌群落多样性。DGGE指纹图谱分析结果表明,油茶林土壤微生物类群的细菌多样性较丰富,各个样品的条带数目稳定分布在13-36条。10年龄油茶人工林细菌基因多样性较为丰富,集约经营10年龄油茶林的细菌物种数量多。细菌丰富度和Shannon-Wiener多样性指数在林龄变化上均表现为中龄林（2个10年龄）〉成熟林（30年龄、50年龄）〉幼龄林（1年龄、6年龄）;其在季节变化上均呈一致的变化规律,为夏季〉秋、冬季〉春季。细菌16S rDNA的系统发育分析结果表明,大多数序列与未培养细菌的同源性较高,所有序列与数据库中16S rDNA序列的相似性在84%-99%。遗传关系研究得到主要的优势菌为泛菌属Pantoea sp.、肠杆菌属Enterobacter sp.。

In order to learn the characteristics of soil microbial community structure of Camellia oleifera forest,and to reveal the responding mechanism of variation characteristics of soil microbial community structure diversity of C.oleifera forest on the environmental factors of forest ages,seasons,and so on,and to provide a theoretical basis for reasonable operation and management of C.oleifera forest,taking 24 soil samples in C.oleifera forest at different ages at Yushui District of Xinyu City of western Jiangxi as research objects,soil bacterial community diversity of C.oleiferaforest was analyzed by using PCR-DGGE technology.The results of DGGE fingerprint analysis showed that soil bacterial diversity of C.oleifera forest was relatively rich,and the number of bands of each sample was from 13 to 36.The soil bacterial genetic diversity of ten-year artificial forest was the most abundant,and number of bacterial strains in ten-year forest through intensive operation was the most.Based on bacterial richness and Shannon-Wiener diversity index from high to low,the order was middle age forest（two 10-year forests）,mature forest（30-year and 50-year forests）,and young forest（1-year and 6-year forests）.The two indexes showed a seasonal variation consistent,the values in summer were higher than those in autumn and winter,and the values were the lowest in spring.The results of phylogenetic analysis of bacterial 16 S rDNA showed that,most sequences had high homology with uncultured bacteria,and the similarity of the 16S rDNA sequences was between 84%-99%.The results of genetic relationship analysis showed that,the dominant bacteria were Pantoea sp and Enterobacter sp.