小蓬竹根际土壤可培养微生物及其酶活性研究

发布时间：2018-07-11 12:16

本文选题：小蓬竹 + 土壤酶　；参考：《贵州大学》2015年硕士论文

【摘要】：小蓬竹作为贵州喀斯特山地适生性竹种,在IUCN红色名录中,被定为极危种,对喀斯特地区水源涵养、水土保持、养分平衡等生态功能的实现起着重要作用。本文以罗甸县小蓬竹根际土壤为研究对象,采用稀释平板法,挑选菌落形态差异的菌株,分离纯化小蓬竹根际土壤细菌、真菌和放线菌,对其16S rDNA(细菌、放线菌)、ITS rDNA(真菌)序列进行分析构建系统发育树,研究根际土壤可培养微生物多样性。同时,对小蓬竹根际土壤相关理化性质进行了研究,为小蓬竹的保护以及喀斯特山地土壤微生物多样性研究,提供一定的理论依据和技术支撑。主要研究结果如下:(1)小蓬竹根际土壤酶研究发现,过氧化氢酶活性8.74mL KMnO4?g-1?min-1;蔗糖酶的活性表示为2.64mg?g-1?d-1;脲酶的活性为0.04mg NH3-N?g-1?d-1;蛋白酶的活性表示为0.10mg NH2-N?g-1?d-1;碱性磷酸酶的活性高于中性磷酸酶的活性,分别为7.97mg P2O5?g-1?d-1、6.11mg P2O5?g-1?d-1。(2)小蓬竹根际土壤微生物数量为细菌数量放线菌数量真菌数量。每克干土中所含细菌、真菌、放线菌的平均数量分别为8.32×107 cfu·g-1、2.32×106 cfu·g-1、9.19×105 cfu·g-1。(3)采用稀释平板法分离小蓬竹根际土壤微生物,共获得菌落表型差异的细菌41株、放线菌20株、真菌33株。16S rDNA有效序列进行BLAST显示,41株细菌可划分为26个分类单元、放线菌可划分为15个分类单元均为链霉菌属(Streptomyces);真菌的ITS rDNA有效序列分析,可划分为24个分类单元。仅有1株真菌BLAST比对相似度仅为75%,可能为新种或属,其余菌株相似性均≥97%。细菌和真菌的Shannon-Wiener多样性指数H分别为1.0679、2.2180,丰富度指数S分别为7、12,均匀度指数J分别为0.5488、0.8926,及优势度指数D分别为0.5217、0.1295。(4)小蓬竹根际土壤细菌、放线菌基于16S rDNA序列建立系统发育树表明,29株细菌属于厚壁菌门(Firmicutes)(70.73%)(按单元种类数计算百分比),11株属于变形菌门(Proteobacteria)(26.83%),1株属于拟杆菌门(Bacteroidetes)2.44%,其中芽孢杆菌属(Bacillus)占绝对优势;分离获得的20株放线菌均为链霉菌属。ITS rDNA系统发育树分析,小蓬竹根际土壤真菌类群子囊菌门类群(占真菌总菌株数的96.97%),青霉菌属(Penicillium)、木霉属(Trichoderma)、曲霉属(Aspergillus)占绝对优势,占总菌株数51.51%,只有1株真菌属于担子菌门的菌属(Perenniporia),占真菌总菌株数的3.03%。(5)小蓬竹根际土壤中微生物的总数较多,细菌的数量上占优势,真菌的多样性指数较高,放线菌仅为1个属但种类较多,总体上小蓬竹根际土壤中含有较为丰富的微生物多样性。
[Abstract]:As a suitable species of bamboo in Guizhou karst mountain area, it is regarded as an extremely dangerous species in IUCN red list, which plays an important role in the realization of ecological functions such as water conservation, soil and water conservation, nutrient balance and so on. In this paper, the rhizosphere soil of Xiaopeng bamboo in Luodian County was studied. The bacteria, fungi and actinomycetes in rhizosphere soil were isolated and purified by dilution plate method, and 16s rDNA (bacteria) were isolated and purified. The phylogenetic tree of its rDNA (fungi) was constructed to study the diversity of culturable microorganisms in rhizosphere soil. At the same time, the physical and chemical properties of rhizosphere soil were studied in order to provide some theoretical basis and technical support for the protection of Xiaobang bamboo and the study of soil microbial diversity in karst mountains. The main results are as follows: (1) the soil enzymes in rhizosphere of Phyllostachys amurensis were found. The activity of catalase was 8.74 mL KMnO _ 4 / g ~ (-1) 路min ~ (-1); the activity of sucrase was 2.64 mg / g ~ (-1) 路d ~ (-1); the activity of urease was 0.04mg NH _ 3-Nng ~ (-1) / d ~ (-1); the activity of protease was expressed as 0.10mg NH _ 2-N _ (g-1) ~ (-1) d ~ (-1); the activity of alkaline phosphatase was higher than that of neutral phosphatase. The results showed that the number of microbes in rhizosphere soil was 7.97mg P _ 2O _ 5 路g ~ (-1) d ~ (-1) 6.11mg P _ 2O _ 5 路g ~ (-1) 路d ~ (-1) 路d ~ (-1). The average number of bacteria, fungi and actinomycetes per gram dry soil was 8.32 脳 10 ~ 7 cfu g ~ (-1) 2.32 脳 10 ~ (6) cfu g ~ (-1) ~ (-1) 9.19 脳 10 ~ 5 cfu ~ (-1) g ~ (-1) respectively. (3) A total of 41 strains of bacteria and 20 strains of actinomycetes were isolated from rhizosphere soil by dilution plate method. 33 strains of fungi. 16s rDNA effective sequence showed that 41 strains of bacteria could be divided into 26 taxonomic units, actinomycetes could be divided into 15 taxonomic units were Streptomyces, fungi its rDNA effective sequence analysis, can be divided into 24 taxonomic units. Only one fungus blast had only 75 similarity, which might be a new species or genus, and the other strains were more than 97% in similarity. The Shannon-Wiener diversity index (H) of bacteria and fungi was 1.0679 (2.2180), the richness index (S) was 7.12, the evenness index (J) was 0.5488 (0.8926), and the dominance index (D) was 0.5217 (0.1295). (4) the bacteria in rhizosphere soil. Phylogenetic tree of actinomycetes based on 16s rDNA sequence showed that 29 strains belong to Firmicutes (70.73%) (calculated by the number of unit species) 11 strains belong to Proteobacteria (26.83%) and 1 strain belongs to Bacteroidetes 2.444.Bacillus is the dominant strain. The 20 actinomycetes isolated were all streptomyces. Its rDNA phylogenetic tree analysis showed that ascomycetes of rhizosphere soil fungi group (96.97%), Penicillium, Trichoderma and (Aspergillus) were the dominant ones. Only one fungus belongs to Perenniporia, which accounts for 3.03 of the total strains. (5) the total number of microbes in rhizosphere soil is more, the number of bacteria is dominant, and the diversity index of fungi is higher. Actinomycetes belong to only one genus but there are many species. In general, there are abundant microbial diversity in rhizosphere soil of Phyllostachys vulgaris.
【学位授予单位】：贵州大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：S714.3

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