根结线虫土壤微生物多样性研究

发布时间：2018-01-27 03:10

本文关键词： 根结线虫根际细菌真菌宏基因组学种群多样性变化　出处：《云南大学》2015年硕士论文　论文类型：学位论文

【摘要】：根结线虫是一类植物寄生性线虫,会引起植物根形成根结,并更容易让植物感染其他病害,造成我国农业损失惨重。而根结线虫病的发生与作物根际微生物有密不可分的关系。本文以根结线虫病害土壤为研究对象,用高通量测序方法研究根结线虫不同病害程度土壤的微生物群落结构和动态演变规律,挖掘不同时间、地点的优势菌群,为探索预防根结线虫危害作物新策略提供理论基础。结果如下： 1、比较分析根结线虫病害土壤的细菌群落结构。主要优势细菌门主要有变形菌门、绿弯菌门、泉古菌门、放线菌门。主要优势细菌科有Nitrososphaeraceae、 Gaiellaceae、Xanthomonadaceae、Nocardioidaceae、Gemmataceae、Pseudomonadaceae、主要优势细菌属有Candidatus Nitrososphaera、Acinetobacter、Rubrobacter、 Pseudomonas。与元谋其他土壤相比,元谋病重土壤中变形菌门、放线菌门所占比例增加,泉古菌门、Nitrososphaeraceae、Candidatus Nitrososphaera Xanthomonadaceae和Pseudomonadaceae所占比例降低。根结线虫的种群密度影响了土壤细菌种类,健康土壤比患病土壤含有更多的细菌种类,病重土壤比病轻土壤含有更丰富的细菌种类。随着根结线虫的种群密度变化,有较大变化的细菌种类是变形菌门、放线菌门、Pseudomonadaceae、Nitrososphaeraceae、Candidatus Nitrososphaera、Pseudomonas。 2、比较分析了根结线虫病害土壤不同时段细菌群落结构。玉溪土壤的优势细菌门有变形菌门、泉古菌门、放线菌门、绿弯菌门。优势细菌科有Nitrososphaeraceae、Xanthomonadaceae、Micrococcaceae、Comamonadaceae、 Chitinophagaceae.Nocardioidaceae.优势细菌属有Candidatus Nitrososphaera、 Kaistobacter、Rhodoplanes、Hydrogenophaga、Nitrospira。随着时间变化,根结线虫种群密度降低,细菌种类更丰富,泉古菌门、Nitrososphaeraceae、Candidatus Nitrososphaera所占比例降低,而绿弯菌门增加。根结线虫数目的变化程度影响着细菌种类和所占比例。 3、比较分析根结线虫病害土壤的真菌群落结构。优势真菌门主要有子囊菌门、接合菌门、担子菌门。优势真菌科有Mucoraceae、Pleosporaceae、Incertae_sedis、 Mycosphaerellaceae。优势真菌属有Alternaria、Myrothecium、Cladosporium、 Rhizopus、Volvopluteus。随着根结线虫种群密度增加,真菌种类更加丰富,子囊菌门、Pleosporaceae、Incertae_sedis、Alternaria和Myrothecium所占比例增加。在根结线虫数目较少的土壤中Rhizopus、Aspergillus、Cladosporium和Volvopluteus所占比例较大。 4、通过分离纯化培养,我们得到353株细菌、113株放线菌和54株真菌。对得到的细菌、放线菌和真菌测定根结线虫校正致死率。分别挑选出每份土壤中校正致死率较高的10株细菌,10株放线菌和10株真菌,提取DNA, PCR扩增,送到华大基因测序,测序后进行BLAST比对。共鉴定了3株真菌、12株放线菌和7株细菌。真菌属于子囊菌门下的曲霉属和木霉属。放线菌属于链霉菌属。两株细菌属于变形菌门下的不动杆菌属。其他的细菌属于厚壁菌门下的芽孢杆菌属。本论文的创新点有： 1.运用宏基因组学技术,比较研究了随时间变化,根结线虫患病土壤的细菌群落结构的变化。 2.运用宏基因组学技术,比较研究了根结线虫患病土壤和健康土壤的真菌群落结构的异同点。
[Abstract]:Root knot nematode is a kind of plant parasitic nematode , which causes root knot of plant root and makes it easier for plant to infect other diseases , which causes heavy agricultural loss in our country . The results are as follows : 1 . The bacterial community structure of soil with root knot nematode disease was analyzed . The main dominant bacteria were as follows : The main dominant bacteria were as follows : 1 . Nitrososphaeraceae , Gaiellaceae , Pseudomonas monadaceae , Nocardioidaceae , Gemmataceae , Pseudomonadaceae . 2 . The bacterial community structure of root knot nematode disease was analyzed . The dominant bacterial door of Yuxi soil was deformed bacteria door , spring ancient fungus door , actinomyces door , and green bending fungus door . The dominant bacteria were Nitrososphaeraceae , Neisseria monadaceae , Micrococcaceae , Comamonadaceae , Chitinaceae , Nocardioidaceae . 3 . Comparative analysis of the fungal community structure of root knot nematode disease soil . The dominant fungus door is mainly composed of ascomycete , zygotic and basidiomycoporaceae . The dominant fungi are Mucoraceae , Pleosporaceae , Incertae _ sedis , Mycosphaerellaceae . 4 . We obtained 353 bacteria , 113 actinomyces and 54 fungi by isolation and purification . Ten strains of bacteria , 10 strains of actinomyces and 10 fungi were isolated from each soil , 10 strains of actinomyces and 10 fungi were selected , DNA was extracted , 12 strains of actinomyces and 7 bacteria were obtained . The innovation points of this paper are as follows : 1 . Using macro - genomics to compare the changes of bacterial community structure with time - varying and root - knot nematode disease . 2 . Using the technique of macro - genomics , the similarities and differences of fungal community structure of root - knot nematode affected soil and healthy soil were compared .

【学位授予单位】：云南大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：S432.45

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