You Ruiqiang, Yu Yang, Shen Min, Zhang Yanzhou, Hong Jian, Kang Yijun
Jiangsu Key Laboratory for Bioresources of Saline Soils, Yancheng Teachers University, Yancheng, Jiangsu, China.
College of Environmental Science and Engineering, Yangzhou University, Yangzhou, China.
Front Microbiol. 2024 Oct 1;15:1447782. doi: 10.3389/fmicb.2024.1447782. eCollection 2024.
The objective of this study was to investigate the impact of various chemical nitrogen fertilizers on the profile of antibiotic resistance genes (ARGs) in soil. A microcosm experiment was conducted with four treatments, including CK (control with no nitrogen), AN (ammonium nitrogen), NN (nitrate nitrogen), and ON (urea nitrogen), and the abundance of ARGs was assessed over a 30-day period using a metagenomic sequencing approach. The levels of core ARGs varied between 0.16 and 0.22 copies per cell across different treatments over time. The abundance of core ARGs in the ON treatment closely resembled that of the CK treatment, suggesting that environmentally friendly nitrogen fertilizers, particularly those in controlled release formulations, may be preferable. The core ARG abundance in the AN and NN treatments exhibited noticeable fluctuations over time. Overall, chemical nitrogen fertilizers had minimal effects on the core ARG profile as determined by principal component analysis and clustering analyses. Conversely, distinct and significant changes in bacterial communities were observed with the use of different nitrogen fertilizers. However, the influence of nitrogen fertilizers on the core ARGs is limited due to the unaffected potential bacterial hosts. Nitrogen-cycling-related genes (NCRGs), such as those involved in nitrogen-fixing (, , ) and denitrification (, , , , ) processes, exhibit a positive correlation with ARGs (, , , ), indicating a potential risk of ARG proliferation during intense denitrification activities. This study indicates that the application of chemical nitrogen has a minimal effect on the abundance of ARGs in soil, thereby alleviating concerns regarding the potential accumulation of ARGs due to the use of chemical nitrogen fertilizers.
本研究的目的是调查各种化学氮肥对土壤中抗生素抗性基因（ARGs）谱的影响。进行了一项微观试验，设置了四个处理组，包括CK（不施氮对照）、AN（铵态氮）、NN（硝态氮）和ON（尿素态氮），并采用宏基因组测序方法在30天内评估ARGs的丰度。随着时间推移，不同处理组中核心ARGs的水平在每细胞0.16至0.22拷贝之间变化。ON处理组中核心ARGs的丰度与CK处理组非常相似，这表明环境友好型氮肥，特别是控释配方的氮肥，可能更可取。AN和NN处理组中核心ARGs的丰度随时间呈现出明显波动。总体而言，通过主成分分析和聚类分析确定，化学氮肥对核心ARGs谱的影响最小。相反，使用不同氮肥时观察到细菌群落有明显且显著的变化。然而，由于潜在细菌宿主未受影响，氮肥对核心ARGs的影响有限。与氮循环相关的基因（NCRGs），如参与固氮（ ， ， ）和反硝化（ ， ， ， ， ）过程的基因，与ARGs呈正相关（ ， ， ），表明在强烈反硝化活动期间存在ARGs增殖的潜在风险。本研究表明，化学氮肥的施用对土壤中ARGs的丰度影响最小，从而减轻了因使用化学氮肥而导致ARGs潜在积累的担忧。
