摘要

抗生素抗性基因（ARGs）和抗生素抗性细菌（ARB）在土壤环境中的日益普及对公众健康构成严重威胁。在这项研究中，研究了不同年份粪便修正的蔬菜土壤中ARG和移动遗传元素（MGEs）的多样性和丰度。总共八个基因，包括四个四环素抗性基因：tetW，tetM，tetO和tetT;两种磺胺抗性基因：sul1和sul2;和两个MGE：intI1和intI2;在10种蔬菜土壤中定量。用粪肥改良的土壤中ARGs的相对丰度显着高于没有施用粪肥的土壤中ARGs的相对丰度。 intI1和intI2基因的相对丰度与tetW，tetO，sul1和sul2基因的相对丰度显着正相关。在不同浓度的抗生素下，粪便改良土壤的抗性菌率远高于对照土壤。在两种抗生素中均检测到芽孢杆菌和Chryseobacterium，更可能是多重耐药细菌。此外，在Cu和Zn的浓度与ARG之间发现了显着的相关性。我们的研究结果提供了经验证据，表明ARGs和ARB在长期粪便修正的蔬菜土壤中的传播风险，这可能促进制定有效的策略，以减少ARGs在农业生态系统中的传播。

The increasing prevalence of antibiotic resistance genes (ARGs) and antibiotic resistant bacteria (ARB) in the soil environment represents a serious threat to public health. In this study, the diversity and abundance of ARGs and mobile genetic elements (MGEs) in different years of manure-amended vegetable soils were investigated. A total of eight genes, including four tetracycline resistance genes: tetW, tetM, tetO and tetT; two sulfonamide resistance genes: sul1 and sul2; and two MGEs: intI1 and intI2; were quantified in ten vegetable soils. The relative abundance of ARGs in soils amended with manure was significantly higher than that in soils without manure application. The relative abundance of the intI1 and intI2 genes had significantly positive correlations with the relative abundance of the tetW, tetO, sul1 and sul2 genes. Under different concentrations of antibiotics, the resistant bacteria rates of manure-amended soil were much higher than the control soil. Bacillus and Chryseobacterium, more likely to be multi-drug-resistant bacteria, were detected in both two antibiotics. Moreover, the significant correlation was found between the concentrations of Cu and Zn and the ARGs. Our findings provide empirical evidence that the dissemination risk of ARGs and ARB in long-term manure-amended vegetable soils, which might promote to the development of effective strategies to reduce the spread of ARGs in agro-ecosystems.

https://www.ncbi.nlm.nih.gov/pubmed/30453260