Sharma Sushma, Singh Dileep K
Department of Zoology, University of Delhi, Delhi, 110007 India.
Indian J Microbiol. 2017 Mar;57(1):92-99. doi: 10.1007/s12088-016-0634-0. Epub 2016 Dec 10.
Biological nitrogen fixation is one of the most important nutrient processes in the ecosystem. Many studies have estimated the variations in soil diazotrophic communities across the globe. To understand the dynamics of nitrogen fixing bacterial communities and their response to the environmental changes, it is important to study the temporal variability of these communities. Using DNA fingerprinting method, denaturing gradient gel electrophoresis and real time polymerase chain reaction of the H gene, we have found that the agricultural land harbored unique nitrogen fixing communities that revealed different temporal patterns and abundance. Variation in soil moisture, organic carbon content, ammonium and nitrate concentrations may be the main factors which influenced the diazotrophic community composition and H gene abundance. species were more dominant in the agricultural soil. Unique environmental factors and agricultural practices were responsible for the temporal shifts in bacterial community structures and H transcripts level. Our study expands understanding of the influence of environmental factors on diazotrophic population that contributes to the nitrogen pool.
生物固氮是生态系统中最重要的养分过程之一。许多研究已经估算了全球土壤中固氮微生物群落的变化情况。为了了解固氮细菌群落的动态变化及其对环境变化的响应,研究这些群落的时间变异性很重要。通过使用DNA指纹图谱方法、变性梯度凝胶电泳以及H基因的实时聚合酶链反应,我们发现农田中存在独特的固氮群落,这些群落呈现出不同的时间模式和丰度。土壤湿度、有机碳含量、铵和硝酸盐浓度的变化可能是影响固氮微生物群落组成和H基因丰度的主要因素。某些物种在农业土壤中更为占优势。独特的环境因素和农业实践导致了细菌群落结构和H转录本水平的时间变化。我们的研究扩展了对环境因素对固氮菌群影响的理解,这些固氮菌群对氮库有贡献。