(gactachvgggtatctaatcc)和341F(cctacgggnggcwgcag)用于放大土壤封闭食物链系统中每个组件的V3-V4区域。Studies have shown that the V3-V4 region of the selected bacteria can reduce genomic heterogeneity and can be closer to the full-length comparison information than other variable regions(DONG-LEI S et al.,2013).The PCR amplification reaction consisted of 1 µL of 10 mM upstream and downstream primers (805 R primer with Barcode at the 5 ' end), 25 µL of Ex Taq酶,1 µL DNA模板和22 µL DDH2O形成50 µL×2反应系统。表4-1显示了特定的PCR扩增反应条件。放大后,通过DNA纯化和恢复试剂盒(Thermo Fisher)回收产物。确定纯化产物的浓度,并将每个样品与