多效唑对芒果园土壤细菌多样性的影响及PICRUSt基因功能预测分析

为了探究多效唑对芒果园土壤微生物多样性和群落结构的影响,本研究以海南乐东某芒果园为研究对象,设置施用和不施用多效唑的土壤分别为处理组和对照组,通过Illumina Miseq测序平台对芒果园土壤进行16S rRNA高通量测序分析。2组样品通过高通量测序共得到3586个OTUs(operational taxonomic units),可注释到38个门、89个纲、195个目、378个科、673个属、1353个种。Alpha多样性分析表明,施用多效唑后,土壤细菌丰富度指数显著高于同时期未施用多效唑的土壤;但施药后土壤的细菌多样性显著降低。主成分分析表明,施用多效唑对土壤细菌的群落结构产生影响。与对照组相比,施用多效唑的土壤中变形菌门和浮霉菌门等含量显著增高,而放线菌门和厚壁菌门等含量显著降低。PICRUSt功能预测分析结果表明,芒果园土壤细菌主要涉及细胞生长与死亡、碳水化合物代谢、次生产物代谢的生物合成、氨基酸代谢等43个子功能,表现出功能上的丰富性。多效唑处理后,会降低土壤细菌的整体代谢能力。由此可见,施用多效唑会降低土壤细菌的多样性,改变土壤细菌的相对丰度,且对土壤细菌的功能会有一定的影响。

Effects of Paclobutrazol on Soil Bacterial Diversity in Mango Orchard and PICRUSt-based Predicted Metagenomic Analysis

The Illumina Miseq 16S rRNA high-throughput sequencing technology was used to study the bacterial community structure and diversity of two group soil samples with and without paclobutrazol treatment, respectively, from a mango orchard in Ledong, Hainan. A total of 3586 operational taxonomic units (OTUs) in two groups were obtained, which were classified as 38 phylums, 89 classes, 195 orders, 378 families, 673 genera and 1353 species. The results of the analysis of Alpha diversity showed that soil bacterial richness index was significantly higher in the paclobutrazo-treated soils, however compared with the soils without paclobutrazol treatment, the bacterial diversity was significantly decreased. The principal component analysis indicated that the community structure of soil bacteria was affected by paclobutrazol. The quantities of Proteobacteria and Planctomycetes were significantly increased in the paclobutrazol-treated soils, however, those of Actinobacteria and Firmicutes were significantly decreased. The PICRUSt analysis showed that the functional gene families were mainly related to 43 sub-functions including the cell growth and death, carbohydrate metabolism, biosynthesis of secondary metabolites, amino acid metabolism, and so on. The total metabolic capacity of soil bacteria could be reduced after treated with paclobutrazol. Therefore, the application of paclobutrazol can reduce the diversity of soil bacteria, and it also has some impacts on the relative abundance and functions of soil bacteria.