抗生素抗性在杀菌剂-抗生素复合污染果蔬种植系统中的形成与传播机制

The high-frequency and high-dose application of agricultural fungicides in the greenhouse production of fruits and vegetables and the substantial use of the antibiotic-contaminated livestock and poultry manure in agricultural soil as organic fertilizer led to the long-term combined contamination of fungicides and antibiotics. Therefore, the diversity of antibiotic resistance genes (ARGs) and the formation and transmission mechanism of antibiotic resistance in the fruits and vegetables planting system contaminated by fungicides and antibiotics are becoming a research hotspot. In this project, the commonly used fungicide carbendazim and the typical tetracycline chlortetracycline are selected as target compounds. The objectives of this project are: 1) to investigate the degradation and accumulation of fungicides and antibiotics in soil, fruits and vegetables; 2) to examine the changes of microbial community structural diversity in soil, fruits and vegetables; 3) to explore the diversity, abundance, and transferability of ARGs in soil, fruits and vegetables; 4）to reveal the formation and development of pollution-induced community tolerance in soil, fruits and vegetables; and 5) to isolate and identify antibiotic resistant bacteria (ARB) and determine resistance level and migration of ARB in soil, fruits and vegetables. This project will elucidate the migration and accumulation characteristics of fungicide and antibiotic residues in greenhouse fruits and vegetables planting system, ascertain the diversity, abundance, and transferability of ARGs in combination with the isolation, identification, resistance level, and migration of ARB in soil and epiphytic and endophytic ARB in fruits and vegetables, and eventually reveal the formation and transmission mechanism of antibiotic resistance in fruits and vegetables planting system under the long-term combined pollution of fungicides and antibiotics. The results will provide a scientific basis for the ecological risk assessment of antibiotic resistance and the safety of agricultural products in fruits and vegetables planting system contaminated by fungicides and antibiotics.

设施果蔬生产中农用杀菌剂高频、高剂量使用和含抗生素残留的畜禽粪肥作为有机肥大量频繁施入农业土壤造成杀菌剂和抗生素长期复合污染。因此，复合污染果蔬种植系统中抗生素抗性基因多样性、抗性形成与传播机制是当前研究热点。本项目选择常用农用杀菌剂多菌灵和典型四环素类抗生素金霉素，研究：1）杀菌剂和抗生素在土壤和果蔬中的降解与积累；2）复合污染土壤和果蔬中微生物群落结构多样性变化；3）复合污染土壤和果蔬中抗性基因多样性、丰度与移动性；4）复合污染诱导微生物群落抗性形成与发展；5）土壤和果蔬中抗性菌分离鉴定、抗性水平与迁移性。研究可望阐明果蔬系统中复合污染迁移累积特征，明确抗性基因多样性、丰度与移动性，并结合土壤、果蔬附生与内生抗性菌分离鉴定、抗性水平与迁移性，从而揭示抗生素抗性在杀菌剂-抗生素复合污染果蔬种植系统中的形成与传播机制，可为复合污染果蔬生产中抗生素抗性生态风险性评价和农产品安全提供科学依据。

设施果蔬生产中农用杀菌剂高频、高剂量使用和含抗生素残留的畜禽粪肥作为有机肥大量频繁施入农业土壤造成杀菌剂和抗生素长期复合污染。因此，研究复合污染果蔬种植系统中抗生素抗性基因多样性、抗性形成与传播机制具有重要的科学和现实意义。本项目基于番茄、草莓等果蔬种植系统研究了多菌灵等常用农用杀菌剂和金霉素等典型抗生素在果蔬及种植土壤中的降解与积累行为以及微生物组与抗性组结构与功能的变化，重点开展了复合污染果蔬种植系统中抗性基因迁移传播机制研究。主要研究结果包括：1）阐明了番茄等果蔬及土壤中多菌灵、金霉素等的降解与积累特征；2）明确了番茄等果蔬及土壤中微生物群落结构多样性变化；3）探明了番茄等果蔬及土壤中抗性基因多样性、丰度与移动性的变化；4）明确了番茄及土壤中微生物群落诱导抗性的变化；5）分析了番茄等果蔬及土壤中抗性菌多样性、抗性水平与迁移性；6）揭示了复合污染果蔬种植系统中抗生素抗性的形成与传播机制。相关成果已在Microbiome、Journal of Hazardous Materials等国内外学术期刊发表标注论文17篇，其中SCI论文16篇；已培养研究生5名，其中博士生2名，硕士生3名。研究结果为复合污染果蔬生产中抗生素抗性生态风险性评价和农产品安全提供了科学依据。