摘要
【目的】土壤微生物在菜田生态系统中具有重要的生态功能,通过16S rRNA基因克隆文库技术分析典型菜田土壤细菌群落结构的组成情况,为揭示典型的菜田土壤微生物的多样性以及土地利用变化与生态环境效应之间的关系奠定基础。【方法】采用未培养技术直接从北京和山东两地典型菜田土壤样品中提取微生物总的DNA,分别构建基于通用引物PCR扩增的土壤细菌16S rRNA基因克隆文库,通过HinfⅠ和HaeⅢ限制性内切酶对两地土壤细菌16S rRNA基因文库中的克隆进行ARDRA(Amplified Ribosomal DNA Rstriction Analysis)分析,将所有阳性克隆分为若干个可操作分类单元(OTU)。【目的】通过构建两地细菌克隆文库的系统发育树,并分析主要种群的组成表明:北京和山东菜田土壤细菌克隆文库的优势种群均为γ、β、α变形细菌亚群。两地的细菌种类组成分别包括124个OTUs和92个OTUs。【结论】北京地区和山东地区典型蔬菜地土壤细菌种群中优势种群均为变形细菌,但是土壤细菌多样性降低,这可能与典型菜田的多年连作,种植蔬菜种类单一直接相关。同时,也可能是造成菜田土壤病害普遍发生,土壤退化的一个重要原因。
[Objective] Soil microorganisms play an important role in the vegetable soil ecosystem. Through 16S rRNA gene cloning library technology to analysis the composition of bacteria community structure in the typical vegetable soil. To revealed the microbial diversity in the typical vegetable soil, and laid the foundation for the relationship between land-use changed and the ecological environment. [Methods] Total microbial DNA was directly extracted from a typical vegetable soil of Beijing and Shandong province. The clone library of 16S ribosomal RNA genes was amplified using PCR with universal bacterial primer sets. The PCR products were then subcloned into pGEM-T vector. Each unique restriction frag- ment polymorphism pattern, created by using two restriction endonucleases （Hinf Ⅰ and Hae Ⅲ）, was designated as an operational taxonomic unit （OTU）. Amplified DNA was used for diversity analysis. [Results] Constructed bacterial phylogenetic trees of the samples revealed the γ-proteobacteria, β-proteobacteda and u-proteobacteria groups were dominant in both clone libraries. Bacterial species composition from Beijing and Shandong province included 124 OTUs and 92 OTUs, respectively. [Conclusion] the dominant species of bacteria populations are proteobacteria in the typical vegetable soil of Beijing and Shandong areas. But bacterial diversity in the two typical vegetable soil samples was reduced. This phenomenon may be directly related to Continuous cultivation for many years and plant a single vegetable species. At the same time, this phenomenon may also be an important reason to cause vegetable soil diseases widespread occurred and soil degradation.
出处
《微生物学报》
CAS
CSCD
北大核心
2008年第10期1344-1350,共7页
Acta Microbiologica Sinica
基金
"十一五"国家科技支撑计划课题(2006BAD07B03
2006BAD08A08
2006BAD17B08)
农业公益性行业科研专项经费项目(NYHYZX07-050)~~
关键词
土壤细菌群落
16SRRNA基因
ARDRA
系统发育分析
bacterial diversity
16S rRNA gene clone library
amplified ribosomal DNA restriction analysis
phylogenetic analysis
