铅锌尾矿区土壤有机菌肥改良后植物根际菌群的特性及多样性研究

Study of characteristics and diversity of rhizospheric microflora from the lead-zinc tailing area of soil improved by organic fertilizer

以辣椒的根际菌群为研究对象,通过纯培养的正交试验对比分析有机菌肥改良前后根际菌群去除铅锌能力及特性的差异,同时利用Illumina Miseq平台对根际菌群的16S rRNA基因V4区域进行测序,分析细菌群落结构及多样性的变化。结果表明:施用有机菌肥提高了可培养根际菌群去除铅、锌的能力,去除率增量最大分别可达40.2%、12.7%。同时,菌群去除铅的最佳培养条件发生了改变,铅锌浓度和培养基类型对铅去除率影响的显著性有所提高。有机菌肥对锌去除率的影响在试验分析中体现不明显。培养基种类是影响菌群去除铅锌的最主要因素,菌群中的原核生物较真核生物更具去除铅锌的优势。有机菌肥的应用对细菌群落结构产生了一定影响,微生物的相对丰度发生了改变,菌群多样性得到了丰富,但硫杆菌属Thiobacillus仍是绝对的优势菌。

Orthogonal experiment was carried out to compare the differences in removal of lead and zinc by rhizospheric microflora between pepper plant pots applied with and without a specifically prepared organic fertilizer. Combined with Illumina sequencing technique, the characteristics changes in bacterial community structure and diversity were also analyzed. The result showed that the organic fertilizer enhanced the capacity of culturable rhizospheric microflora to remove lead and zinc and the highest removal rate increment reached 40.2% and 12.7%, respectively. The optimum culture condition of lead removal was changed while the effect of lead- zinc concentrations and medium types on lead removal rate increased to higher significant levels. In comparison, the positive effect of organic fertilizer on zinc removal was less significant. Medium type was found to be the main factor affecting lead and zinc removal. Prokaryotes were shown to be more preponderant in removal of lead and zinc than Eukaryotes in the rhizospheric microflora. It was also found the organic fertilizer had an apparent impact on the original microflora, the relative microorganism abundance was changed, the diversity of flora species was enriched, but ThiobaciUus were still the dominant bacteria.