摘要
      缺水是可持续农业发展的主要挑战之一，特别是在发展中国家，因此，用废水灌溉粮食作物已成为一种普遍做法，以满足日益增长的粮食需求。本研究的目的是确定废水灌溉对农业环境中土壤和蔬菜中细菌群落和抗生素耐药性动态的影响。利用16S rRNA基因宏基因组学、鸟枪宏基因组学和分子PCR技术，测定污水灌溉土壤和蔬菜中细菌多样性、抗生素抗性基因的发生和总体动态。废水灌溉后，微宇宙土壤中的蛋白细菌显著减少，坚壁菌门显著增加，细菌群落格局发生了变化。霰弹枪宏基因组学揭示了废水中至少属于九种不同类别抗生素的多种ARG。然而，在灌溉后的微宇宙土壤中仅鉴定出blaTEM（β-内酰胺酶）和aadA（氨基糖苷类）抗性基因序列，在污水灌溉的蔬菜表面（菠菜和甜菜根）上仅检测到blaTEM。从这项研究中，在所有样本中只鉴定出blaTEM基因；污水、污水处理过的土壤和蔬菜。数据表明，β-内酰胺酶blaTEM基因可能从废水中传播并持久存在于农业土壤和蔬菜中。这项研究增强了我们对抗生素耐药性传播的理解，并强调了监测农业系统中抗生素耐药性的重要性，这对于为水资源紧张国家可持续利用废水的政策提供信息至关重要。
Abstract
Water scarcity is one of the main challenges in sustainable agricultural development particularly in developing countries therefore, irrigation of food crops with wastewater effluent has become a common practice in order to meet the growing food demand. The aim of this study was to determine the impact of wastewater irrigation on bacterial community and antibiotic resistance dynamics in soil and vegetables in an agricultural setting. To determine bacterial diversity, occurrence and overall dynamics of antibiotic resistant genes (ARGs) in effluent irrigated soil and vegetables, 16S rRNA gene metagenomics, shotgun metagenomics and molecular PCR technique were utilized. A shift in bacterial community profile was observed as notable reduction in proteobacteria and increase in firmicutes phyla from the microcosm soil following wastewater effluent irrigation. Shotgun metagenomics revealed diverse ARGs belonging to at least nine different classes of antibiotics in the effluent wastewater. However, only blaTEM (beta-lactamase) and aadA (aminoglycoside) resistance gene sequences were identified in microcosm soil following irrigation and only blaTEM was detected on effluent irrigated vegetable surfaces (spinach and beetroots). From the study, only blaTEM gene was identified across all samples; effluent wastewater, effluent-treated soil, and vegetables. The data suggests a possible dissemination and persistence of the beta-lactamase blaTEM gene from effluent wastewater into agricultural soil and vegetables. This study enhances our understanding of antibiotic resistance spread and highlights the importance of monitoring antibiotic resistance in agro-systems, which is critical for informing policies aimed at sustainable use of wastewater effluent in water-stressed countries.

https://www.sciencedirect.com/science/article/pii/S2405844022003772