摘要

    土壤是抗生素抗性基因（ARG）的重要储存库，但我们对它们在农田土壤中的分布和主要驱动力仍然知之甚少。在这里，我们使用高通量定量PCR方法对中国2 200 km样带的105种农田（玉米，花生或大豆种植的）土壤中的ARGs模式进行了调查。总共检测到204个ARG，与中东北和华南地区相比，中部地区发现了更高的多样性。被认为是核心抗药性的最丰富的（前50％）和高度共享的（存在于> 50％的样品中）ARG被多药抗性基因如oprJ，acrA-05和acrA-04所支配。回归分析表明，总ARG和核心抵抗力组的相对丰度均与移动遗传元件（MGE）有着显着的关系。人为因素包括塑料薄膜的消耗和土壤特性（包括重金属）与ARGs的多样性具有良好的相关性。结构方程模型分析进一步说明，人为因素是塑造ARGs模式的主要力量。这些发现凸显了人类活动在塑造农田土壤抗药性抵抗素组中的重要性，提供了潜在的管理策略来减轻ARGs通过食物链向人类的传播。

    Soil is a vital reservoir of antibiotic resistance genes (ARGs), but we still know little about their distribution in cropland soils and the main driving forces. Here we performed an investigation for ARGs patterns in 105 cropland soils (planted with maize, peanut or soybean) along a 2, 200 km transect in China using high-throughput quantitative PCR approaches. Totally, 204 ARGs were detected, with a higher diversity found in central China than that in northeast and south China. The most abundant (top 50%) and highly shared (present in >50% samples) ARGs regarded as core resistome were dominated by multidrug resistance genes such as oprJ, acrA-05 and acrA-04. Regressive analyses revealed that the relative abundance of total ARGs and core resistome both had significant relationships with mobile genetic elements (MGEs). Anthropogenic factors including the consumption of plastic films and soil properties including heavy metals showed good correlations with the diversity of ARGs. Structural equation modelling analysis further explained that anthropogenic factors were the main forces shaping the ARGs patterns. These findings highlight the importance of human activities in shaping soil antibiotic resistome in the croplands, providing potential management strategies to mitigate the dissemination of ARGs to humans via food chain.

    https://www.sciencedirect.com/science/article/abs/pii/S0048969719364149