摘要

       对于肥力相对较低的土壤，施用动物粪便是一种强烈推荐的传统农业实践。然而，对于长江上游地区广泛分布的农田紫色土，以往关于粪肥处理后抗生素抗性组变化的研究知之甚少。在本研究中，使用高通量定量聚合酶链反应和 Illumina 测序评估了长期施用猪粪浆对可耕石灰质紫色土壤中抗生素抗性基因 (ARG) 和细菌群落发生的影响。研究了四种处理，包括不施肥控制 (CK) 和猪粪 (OM)、OM 加矿物氮肥 (OMN) 和 OM 加矿物 NPK 肥料 (OMNPK) 处理。在接受不同处理的所有土壤样品中，共检测到 139 个独特的 ARG 和 6 个移动遗传元件基因，其中多药和 β-内酰胺是两种最主要的 ARG 类型。主坐标分析（PCoA）结果表明，OM 与矿物肥料（即 OMN 和 OMNPK）两个处理的土壤 ARGs 谱与对照处理相似，而接受在其他三种处理中，只有猪粪施用具有与土壤不同的 ARG 模式。在 OM 处理中观察到土壤 ARG 的明显减少。不仅在 ARGs 之间，而且在移动遗传元件 (MGEs) 和 ARGs 之间都发现了显着的正相关关系。然而，在 ARG 模式和细菌群落组成之间没有检测到显着关系。这些结果意味着长期将猪粪浆施用于紫色土壤不会导致 ARGs 的流行；然而，不应忽视 ARGs 在石灰质紫色土壤中水平转移的潜力。

       The application of animal manure is a highly recommended traditional agricultural practice for soils of relatively low fertility. However, for the farmland purple soils that are widely distributed in the upper Yangtze River region, little knowledge has been established in previous studies about the changes in the antibiotic resistome upon manure amendment. In the present study, the impact of long-term pig manure slurry application on the occurrence of antibiotic resistance genes (ARGs) and bacterial community was assessed in arable calcareous purple soil using high-throughput quantitative polymerase chain reaction and Illumina sequencing. Four treatments, including a non-fertilization control (CK) and pig manure (OM), OM plus mineral N fertilizer (OMN) and OM plus mineral NPK fertilizer (OMNPK) treatments were investigated. Across all the soil samples receiving different treatments, a total of 139 unique ARGs and 6 mobile genetic element genes were detected, with multidrug and beta-lactam the two most dominant types of ARGs. The results of the principal coordinate analysis (PCoA) suggest that the profiles of soil ARGs in the two treatments of OM combined with mineral fertilizer(s) (i.e., OMN and OMNPK) were similar to those in the control treatment, while the soil receiving only pig manure application had a different pattern of ARGs from the soils in the other three treatments. A clear reduction of soil ARGs was observed in the OM treatment. Significant and positive relationships were found not only among ARGs but also between mobile genetic elements (MGEs) and ARGs. However, no significant relationships were detected between ARG patterns and bacterial community composition. These results imply that the long-term application of pig manure slurry to purple soil does not lead to the prevalence of ARGs; however, the potential for the horizontal transfer of ARGs in calcareous purple soil should not be ignored.

https://www.sciencedirect.com/science/article/abs/pii/S0048969718329978