摘要
      再生水灌溉条件下土壤中抗生素抗性基因的转移具有潜在的环境风险。NPK肥料的调节可能会影响细菌群落的行为、可移动遗传元素（MGE）和土壤性质，这些因素决定了ARGs的命运。为了确定NPK肥料中的关键元素并实现有效调控，我们探讨了个体N、P、K施肥对番茄根际和大块土壤ARG变化的影响。与未施肥处理相比，N施肥导致ARGs丰度下降幅度更大（下降24.06%-73.09%），而P施肥（增加高达35.84%，下降高达58.80%）或K施肥（下降13.47%-72.47%）。不同形式的N（CO（NH2）2、NaNO3和NH4HCO3）、P（Ca（H2PO4）2和CaMgO4P+）的影响，本研究还研究了K（KCl和K2（SO4））肥料，结果表明，在不同类型的N、P、K肥料中，NaNO3、CaMgO4P+和K2（O4）对降低ARGs丰度的影响更大。细菌群落对施氮反应最强。ARG宿主和非宿主生物的细菌多样性和丰度降低解释了土壤中ARG总丰度的下降。在施用P或K的土壤中，土壤性质，特别是总氮和pH对ARG变化的影响大于细菌群落和MGE。这些结果表明，氮磷钾肥的氮调节可能是降低再生水灌溉土壤中ARGs风险的有效途径。
Abstract
The transfer of antibiotic resistance genes (ARGs) in soil under reclaimed water irrigation poses a potential environmental risk. Regulation of NPK fertilizer could influence the behavior of bacterial communities, mobile genetic elements (MGEs), and soil properties, which determine the fate of ARGs. To identify the key element in NPK fertilizer and realize efficient regulation, we explored the effect of individual N, P, K fertilization on ARG variation in tomato rhizosphere and bulk soils. Compared with an unfertilized treatment, N fertilization resulted in greater decreases in the abundance of ARGs (decreases of 24.06%–73.09%) than did either P fertilization (increases of up to 35.84%, decreases of up to 58.80%) or K fertilization (decreases of 13.47%–72.47%). The influence of different forms of N (CO(NH2)2, NaNO3, and NH4HCO3), P (Ca(H2PO4)2 and CaMgO4P+), and K (KCl and K2(SO4)) fertilizers was also investigated in this study, and showed the influence of NaNO3, CaMgO4P+, and K2(SO4) on reducing ARGs abundance was greater in different types of N, P, K fertilizers. Bacterial communities showed the strongest response to N fertilization. The reduced bacterial diversity and abundance of ARG-host and non-host organisms explained the decline of total ARG abundance in soil. In soils fertilized with either P or K, the effect of soil properties, especially total nitrogen and pH, on ARG variation was greater than that of bacterial community and MGEs. These results suggest that N regulation of in NPK fertilizer may be an effective way to reduce the risks of ARGs in soil associated with reclaimed water irrigation.

https://www.sciencedirect.com/science/article/pii/S0147651322000252