UV-B辐射增强对大豆生理指标及根际细菌多样性的影响

发布时间：2018-03-08 04:10

本文选题：UV-B　切入点：大豆　出处：《聊城大学》2015年硕士论文　论文类型：学位论文

【摘要】：大气中O3浓度下降,导致达到地面的UV-B辐射增强,对农田生态系统带来诸多不利影响,以往的报道多着重于大豆地上部分,UV-B对地下部分及根际微生物影响的报道较少,根瘤菌和大豆是共生作用的典范,根瘤与大豆具有密切的生理关系,在研究UV-B辐射对大豆地上部、地下部及地下部及根际微生物的影响时,无法忽略根瘤菌在其中起的作用。本实验在大田条件下,以相同遗传背景的野生型、多根瘤和无根瘤三种大豆为材料,设置了CK、和模拟UV-B辐射增强15%两个处理,展开对UV-B辐射增强环境下三种大豆生物量、UV吸收物质等生理指标及大豆根际微生物多样性的研究。主要结果如下:UV-B辐射增强使大豆UV吸收物质和MDA含量上升,对大豆生长有抑制作用,最终导致大豆生物量下降,产量下降。通过比较苗期,花期,鼓粒期大豆的生理指标发现多根瘤大豆对UV-B辐射不敏感,抗UV-B胁迫能力强。使用高通量测序方法对根际土细菌16s DNAV4区测序,通过分析OTU(Operational Taxonomic Units,操作分类单元),进行对微生物多样性的研究。结果表明:大豆根际细菌主要是以放线菌门(Actinobacteria)、酸杆菌门(Acidobacteria)、变形菌门(Proteobacteria)、拟杆菌门(Bacteroidetes)和浮霉菌门(Planctomycetes)构成。在大豆的三个生育期,大豆根际土菌落结构分布差异不大。而硝化螺旋菌门(Nitrospirae)等转氨菌含量少,这与土壤中含氮量有关,本次种植的土壤含氮量较低只达到国家土质分类标准中第三类土。根际土壤中菌种相对含量受到UV-B的影响,但是影响效果和细菌的种类有关。
[Abstract]:The decrease of O _ 3 concentration in the atmosphere resulted in the enhancement of UV-B radiation to the surface, which brought many adverse effects to the farmland ecosystem. The previous reports focused on the effects of UV-B on the underground and rhizosphere microbes in the aboveground part of soybean, and there were few reports about the effects of UV-B on the underground and rhizosphere microbes. Rhizobia and soybean are typical symbiosis. Rhizobia have close physiological relationship with soybean. In the study of the effects of UV-B radiation on the aboveground, underground, underground and rhizosphere microorganisms of soybean, rhizobia and rhizosphere of soybean were studied. The effect of Rhizobium on it could not be ignored. In this experiment, three kinds of soybean with the same genetic background, wild type, multiple nodule and nodule free, were used to set up CKand and simulate 15% UV-B radiation enhancement under field condition. The physiological indexes such as UV absorbents of three soybean biomass and their rhizosphere microbial diversity were studied in the environment of enhanced UV-B radiation. The main results were as follows: enhanced UV-B radiation increased the content of UV absorbents and MDA in soybean. The growth of soybean was inhibited, which resulted in the decrease of biomass and the decrease of yield. By comparing the physiological indexes of soybean at seedling stage, flowering stage and grain filling stage, it was found that multi-nodule soybean was insensitive to UV-B radiation. High throughput sequencing method was used to sequence the 16s DNAV4 region of rhizosphere bacteria. The microbial diversity of soybean rhizosphere bacteria was studied by analyzing OTU(Operational Taxonomic units and operating taxonomic units. The results showed that actinobacter teriae, actinobacteriae, Proteobacteriae, Bacteroides and Planctomycetesa were the main components of soybean rhizosphere bacteria (Actinobacterium teriae, Actinobacteria actinobacteriae, Proteobacteriae, Bacteroides) and Planctomycetesa. During the three growth periods of soybean, The distribution of colony structure of soybean rhizosphere soil was not different, but the content of nitro spirae was less, which was related to the nitrogen content in soil. The soil nitrogen content of this planting is lower than that of the third kind of soil in the national soil classification standard. The relative content of bacteria in rhizosphere soil is affected by UV-B, but the effect is related to the species of bacteria.
【学位授予单位】：聊城大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：S565.1;S154.3

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