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土壤古菌和真菌在温室生态系统是仅次于细菌的微生物,具有类似于细菌的重要生态功能。通过构建古菌16S rRNA和真菌18S rRNA基因克隆文库,分析温室黄瓜近根土壤古菌和真菌群落结构组成,为开发利用温室这一特殊的生态环境中丰富的微生物资源以及理解微生物与植物间的互作提供参考依据。采用研磨-冻融-溶菌酶-蛋白酶K-SDS热处理以及CTAB处理等理化方法,提取和纯化微生物总DNA,构建古菌16S rRNA和真菌18S rRNA基因克隆文库。利用DOTUR软件将古菌和真菌序列按照相似性97%的标准分成若干个可操作分类单元(OTUs)。土壤古菌克隆文库主要包括泉古菌门和未分类的古菌两大类,并有少部分广域古菌类群,所有泉古菌均属于热变形菌纲,共45个OTUs;真菌克隆文库包括真菌门的大多数亚门真菌,共24个OTUs,未发现担子菌亚门真菌。古菌多样性比较丰富,且发现少量的广域古菌(甲烷菌),这一情况可能与温室长期高温高湿,高有机质含量,土壤处于缺氧环境有关;土壤真菌的优势种群为子囊菌,占到土壤真菌的80%以上,这可能与绝大多数植物真菌性病害属于土传病害,通过菌丝体、菌核或子囊壳在土壤病残体中越冬有一定的关系。
Soil archaea and fungi are second only to bacteria in the greenhouse ecosystem, with important ecological functions similar to bacteria. By constructing 16S rRNA of archaea and 18S rRNA gene cloning library of fungi, we analyzed the composition of archaeal and fungal communities in the near-root soils of cucumbers in greenhouse. In order to develop and utilize abundant microbial resources in this special ecological environment of greenhouse and to understand the relationships between microorganisms and plants Interaction provide a reference. The total DNA of the microorganism was extracted and purified by physical and chemical methods such as grinding-freezing-thawing-lysozyme-protease K-SDS heat treatment and CTAB treatment, and the archaeal 16S rRNA and the fungal 18S rRNA gene clone library were constructed. Archaeal and fungal sequences were divided into several operable taxonomic units (OTUs) using the DOTUR software based on a similarity of 97%. The archaeal clone library of soil mainly includes two types of ancient archaeal fungi and unclassified archaea, and a small part of wide-area archaeal groups, all of which belong to the genus Thermomyces. There are 45 OTUs in total. The fungal clones The library includes most of the subfamilies of the fungal door, a total of 24 OTUs, and no basidiomycotina is found. The abundance of archaea and the discovery of a small amount of archaea (Methanobacteria) can be related to long-term high temperature and high humidity, high organic matter content and soil hypoxia in the greenhouse. The dominant species of soil fungi are ascomycetes , Accounting for more than 80% of the soil fungi. This may be related to the fact that most plant fungal diseases belong to soil-borne diseases and wintering through soil mycelia, sclerotia or ascus crusts.