摘要

耕地是重要的农业生产方式。如果粪便中携带抗生素抗性的肠道细菌转移到未加工的作物中，人类或动物的食用将成为接触抗生素抗性基因的途径。在施用土地之前处理粪肥是减少其夹带的抗生素抗性基因丰度的潜在管理选择。在本研究中，将未经处理，厌氧消化，机械脱水或堆肥的牛粪施用于田间小区，然后将其种植到生菜，胡萝卜和萝卜中。测定了处理对粪肥组成的影响，施用后土壤中抗生素抗性基因靶标的持久性以及收获时蔬菜中抗生素抗性基因和细菌的分布。与其他肥料相比，堆肥粪肥的抗生素抗性基因目标丰度最低。不同施肥处理对抗生素抗性基因的持久性没有显着差异。与未施肥的土壤相比，生肥和消化粪肥的土壤中抗生素抗性基因的检出率更高，而堆肥土壤中抗生素抗性基因的检出率较低。目前的研究表明，种植在生粪肥或消化粪肥的土壤上的蔬菜有被粪便携带的抗生素抗性细菌污染的风险，而种植在接收堆肥肥料的土壤中生长的蔬菜风险较少。

Manuring ground used for crop production is an important agricultural practice. Should antibiotic-resistant enteric bacteria carried in the manure be transferred to crops that are consumed raw, their consumption by humans or animals will represent a route of exposure to antibiotic resistance genes. Treatment of manures prior to land application is a potential management option to reduce the abundance of antibiotic resistance genes entrained with manure application. In this study, dairy manure that was untreated, anaerobically digested, mechanically dewatered or composted was applied to field plots that were then cropped to lettuce, carrots and radishes. The impact of treatment on manure composition, persistence of antibiotic resistance gene targets in soil following application, and distribution of antibiotic resistance genes and bacteria on vegetables at harvest was determined. Composted manure had the lowest abundance of antibiotic resistance gene targets compared to the other manures. There was no significant difference in the persistence characteristics of antibiotic resistance genes following land application of the various manures. Compared to unmanured soil, antibiotic resistance genes were detected more frequently in soil receiving raw or digested manure, whereas they were not in soil receiving composted manure. The present study suggests that vegetables grown in ground receiving raw or digested manure are at risk of contamination with manure-borne antibiotic resistant bacteria, whereas vegetables grown in ground receiving composted manure are less so.

https://www.sciencedirect.com/science/article/pii/S0048969716328285