The nature of microbial communities and their relation to enzyme activities in desert soils is a neglected area of investigation. To address this, the bacterial diversity and distribution and soil physico-chemical fac...The nature of microbial communities and their relation to enzyme activities in desert soils is a neglected area of investigation. To address this, the bacterial diversity and distribution and soil physico-chemical factors were investigated in the soil crust, the soil beneath the crust and rhizosphere soil at the southeast edge of the Tengger Desert, using the denaturing gradient gel electrophoresis of 16S rRNA genes amplified by the polymerase chain reaction. Phylogenedc analysis of the sequenced DGGE bands revealed a great diversity of bacteria. The Proteobacteria, consisting of the α, β, and γsubdivisions, were clearly the dominant group at all depths and in rhizosphere soil. Analysis of the enzyme activities indicated that the rhizosphere soil of Caragana korshinskii exhibited the highest protease and polyphenol oxidase activities, and in the soil crust there were increased activities of catalase, urease, dehydrogenase and sucrase. The bacterial community abundance closely correlated with soil enzyme activities in different soils. The presence of Cyanobacteria correlated with significant increases in protease, catalase and sucrase in the soil crust, and increased urease in the rhizosphere soil of Artemisia ordosica. The occurrence of Acidobacteria was associated with significant increases in urease, dehydrogenase, and sucrase in the rhizosphere soil of C. korshinski. The presence of γ-Proteobacteria correlated with a significant increase in polyphenol oxidase in the rhizosphere soil ofA. ordosica. The study indicated a close relationship between the soil bacterial community and soil enzymes, suggesting the necessity of further investigations into bacterial function in this desert ecosystem.展开更多
三七是我国特有的中药材,因存在严重的连作障碍,导致三七产量与品质下降.基于Illumina Mi Seq测序平台采用16S r DNA分析技术对三七种植前土壤、种植3年根际土壤、三七收后1年和3年土壤4种类型土壤中的细菌群落多样性进行了分析.结果表...三七是我国特有的中药材,因存在严重的连作障碍,导致三七产量与品质下降.基于Illumina Mi Seq测序平台采用16S r DNA分析技术对三七种植前土壤、种植3年根际土壤、三七收后1年和3年土壤4种类型土壤中的细菌群落多样性进行了分析.结果表明:三七植株的种植对土壤细菌群落组成在门的分类水平上具有显著的影响,三七种植前后变形菌门(Proteobacteria)、蓝藻门(Cyanobacteria)和放线菌门(Actinobacteria)为调查土壤中的的优势细菌门;三七种植使红游动菌属(Rhodoplanes)明显减少而假单胞菌属(Pseudomonas)增加明显;种植三七前后土壤细菌群落多样性指数和丰富度指数的变化规律基本一致,表现出未种植空白对照CK>三七收后3年>三七收后1年>三年生三七根际.展开更多
将养殖粪便进行资源化处理,尤其是将粪便堆肥发酵后变为生物肥料还田,具有重要的经济、社会和生态效益。之前关于细菌在堆肥过程中的研究,大部分采用实验室培养、分离、鉴定的方法,由于受培养方式的限制,仅能分析粪肥中有限的细菌类别。...将养殖粪便进行资源化处理,尤其是将粪便堆肥发酵后变为生物肥料还田,具有重要的经济、社会和生态效益。之前关于细菌在堆肥过程中的研究,大部分采用实验室培养、分离、鉴定的方法,由于受培养方式的限制,仅能分析粪肥中有限的细菌类别。16S r RNA基因作为生物物种的特征核酸序列,被认为是最适于细菌系统发育和分类鉴定研究的指标。本研究使用16S r RNA基因高通量测序技术,分析了牛粪自然发酵与添加益生菌剂发酵过程中细菌种群的多样性变化。结果表明,1)新鲜牛粪、自然发酵1个月、自然发酵6个月的牛粪中细菌种群并没有明显的变化规律,说明自然发酵过程主要依赖于新鲜牛粪中携带的细菌种群;2)添加益生菌发酵后,细菌种群明显不同于不自然发酵过程中的细菌种群,其中变形菌门(Proteobacteria)细菌显著增加,而厚壁菌门(Firmicutes)细菌显著减少,说明益生菌剂能够显著改变堆肥过程中的细菌种群。本研究对于理解牛粪堆肥过程、提高堆肥效果,以及新型堆肥益生菌剂的开发都具有重要意义。展开更多
基金supported by the National Natural Science Foundation of China (No.31100365, 31170465,40971034)the International S&T Cooperation Program of China (No.2011DFA32520)the Science and Technology Projects in Gansu Province (No.1011FKCA114,1010RJZA009)
文摘The nature of microbial communities and their relation to enzyme activities in desert soils is a neglected area of investigation. To address this, the bacterial diversity and distribution and soil physico-chemical factors were investigated in the soil crust, the soil beneath the crust and rhizosphere soil at the southeast edge of the Tengger Desert, using the denaturing gradient gel electrophoresis of 16S rRNA genes amplified by the polymerase chain reaction. Phylogenedc analysis of the sequenced DGGE bands revealed a great diversity of bacteria. The Proteobacteria, consisting of the α, β, and γsubdivisions, were clearly the dominant group at all depths and in rhizosphere soil. Analysis of the enzyme activities indicated that the rhizosphere soil of Caragana korshinskii exhibited the highest protease and polyphenol oxidase activities, and in the soil crust there were increased activities of catalase, urease, dehydrogenase and sucrase. The bacterial community abundance closely correlated with soil enzyme activities in different soils. The presence of Cyanobacteria correlated with significant increases in protease, catalase and sucrase in the soil crust, and increased urease in the rhizosphere soil of Artemisia ordosica. The occurrence of Acidobacteria was associated with significant increases in urease, dehydrogenase, and sucrase in the rhizosphere soil of C. korshinski. The presence of γ-Proteobacteria correlated with a significant increase in polyphenol oxidase in the rhizosphere soil ofA. ordosica. The study indicated a close relationship between the soil bacterial community and soil enzymes, suggesting the necessity of further investigations into bacterial function in this desert ecosystem.
文摘三七是我国特有的中药材,因存在严重的连作障碍,导致三七产量与品质下降.基于Illumina Mi Seq测序平台采用16S r DNA分析技术对三七种植前土壤、种植3年根际土壤、三七收后1年和3年土壤4种类型土壤中的细菌群落多样性进行了分析.结果表明:三七植株的种植对土壤细菌群落组成在门的分类水平上具有显著的影响,三七种植前后变形菌门(Proteobacteria)、蓝藻门(Cyanobacteria)和放线菌门(Actinobacteria)为调查土壤中的的优势细菌门;三七种植使红游动菌属(Rhodoplanes)明显减少而假单胞菌属(Pseudomonas)增加明显;种植三七前后土壤细菌群落多样性指数和丰富度指数的变化规律基本一致,表现出未种植空白对照CK>三七收后3年>三七收后1年>三年生三七根际.
文摘将养殖粪便进行资源化处理,尤其是将粪便堆肥发酵后变为生物肥料还田,具有重要的经济、社会和生态效益。之前关于细菌在堆肥过程中的研究,大部分采用实验室培养、分离、鉴定的方法,由于受培养方式的限制,仅能分析粪肥中有限的细菌类别。16S r RNA基因作为生物物种的特征核酸序列,被认为是最适于细菌系统发育和分类鉴定研究的指标。本研究使用16S r RNA基因高通量测序技术,分析了牛粪自然发酵与添加益生菌剂发酵过程中细菌种群的多样性变化。结果表明,1)新鲜牛粪、自然发酵1个月、自然发酵6个月的牛粪中细菌种群并没有明显的变化规律,说明自然发酵过程主要依赖于新鲜牛粪中携带的细菌种群;2)添加益生菌发酵后,细菌种群明显不同于不自然发酵过程中的细菌种群,其中变形菌门(Proteobacteria)细菌显著增加,而厚壁菌门(Firmicutes)细菌显著减少,说明益生菌剂能够显著改变堆肥过程中的细菌种群。本研究对于理解牛粪堆肥过程、提高堆肥效果,以及新型堆肥益生菌剂的开发都具有重要意义。