摘要

被抗生素污染的沼液和废渣在蔬菜种植中被广泛用作肥料。然而，它们对抗生素抗性基因( ARGs )在菜地中的传播的影响仍然是未知的。采用活菌平板计数、高通量荧光定量PCR ( HT - qPCR )和Illumina MiSeq测序技术来监测从猪粪到田间的抗生素抗性细菌（ARB），ARG和细菌群落。共检测到83个ARGs和3个转座子基因。厌氧消化降低了四环素和大环内酯-林肯酰胺-链脲菌素( MLSB )抗性基因的相对丰度。然而，在沼渣中ARB的数量和相对丰度分别为磺胺类、氨基糖苷类和氟苯尼考、氯霉素和安哌尼考( FCA )抗性基因的270倍和52倍。长期施用沼液和抗生素残留可提高ARB的发生率，增加ARGs和转座子基因的相对丰度。此外，沼液和沼渣处理的土壤与对照样品的细菌群落差异显著，尤其门拟杆菌和放线菌之间。经网络分析，鉴定出19个属为可能的ARGs宿主。研究结果对沼液和沼渣的合理利用具有重要意义。

Biogas slurry and residue contaminated with antibiotics are widely used as fertilizers in vegetable crop planting. However, their impact on the spreading of antibiotic resistance genes (ARGs) in vegetable fields is still largely unknown. In the present study, antibiotic resistant bacteria (ARB), ARGs and bacterial communities from pig manure to fields were monitored by using viable plate counts, high-throughput fluorescent quantitative PCR (HT-qPCR) and Illumina MiSeq sequencing. Eighty-three ARGs and 3 transposons genes were detected. Anaerobic digestion reduced relative abundance of tetracycline and Macrolide-Lincosamide-Streptogramin (MLSB) resistance genes. However, the number of ARB and the relative abundance of sulfa, aminoglycoside and florfenicol, chloramphenicol, and amphenicol (FCA) resistance genes, respectively, enriched up to 270 times and 52 times in biogas residue. Long-term application of biogas slurry and residue contaminated with antibiotics in fields increased the rate of ARB as well as relative abundance of ARGs and transposons genes. Additionally, bacterial communities significantly differed between the soil treated with biogas slurry and residue and the control sample, especially the phyla Bacteroidetes andActinobacteria. Based on network analysis, 19 genera were identified as possible hosts of the detected ARGs. Our results provide an important significance for reasonable application of biogas slurry and residue.

https://www.sciencedirect.com/science/article/pii/S0304389417307872