摘要

       在过去的几十年里，对有机食品，特别是有机蔬菜的需求一直在迅速增长。然而，长期以来一直忽视通过有机生产程序将更多抗生素抗性基因 (ARG) 和抗生素抗性细菌 (ARB) 引入蔬菜的风险。在我们的研究中，通过使用高通量定量 PCR 和 16sRNA Illumina 测序技术，我们调查了传统 (CPL) 和有机生菜 (OPL) 中 ARG 和微生物群落的丰度和多样性。在样品的叶际和叶内生菌中共检测到 134 个 ARG。叶际中 ARG 的绝对拷贝数在 OPL 中比在 CPL 中高 8 倍。我们还观察到 OPL 和 CPL 之间微生物群落的显着差异，并且 OPL 中叶际和叶内生细菌的多样性低于 CPL。 Mantel 检验和变异分区分析 (VPA) 表明 ARG 的分布受细菌群落组成的强烈影响。 ARGs 和细菌分类群之间的网络分析表明，八个细菌家族被认为是 ARGs 的潜在宿主。这些结果提供了对有机农业对蔬菜中细菌和 ARG 成分谱影响的见解。

       The demand for organic food products, especially for organic vegetables has been growing rapidly in the last few decades. However, the risk of introducing more antibiotic resistant genes (ARGs) and antibiotic resistant bacteria (ARB) to the vegetables by organic production procedures has long been overlooked. In our study, by using high-throughput quantitative PCR and 16sRNA Illumina sequencing technology, we investigated the abundance and diversity of ARGs and the microbial communities in conventionally (CPL) and organically produced lettuce (OPL). A total of 134 ARGs were detected in the phyllosphere and leaf endophyte of the samples. Absolute copy numbers of ARGs in phyllosphere were 8-fold higher in the OPL than in CPL. We also observed a significant difference in the microbial communities between OPL and CPL, and a lower diversity of both phyllosphere and leaf endophytic bacteria in OPL than in CPL. The Mantel test and variation partitioning analysis (VPA) suggested that the profile of ARGs is strongly affected by bacterial community compositions. Network analysis between ARGs and bacterial taxa indicated that eight bacterial families were implicated to be the potential hosts of ARGs. These results provide insights into the impacts of organic farming on the profiles of bacterial and ARG compositions in vegetables.

https://www.sciencedirect.com/science/article/pii/S0160412016307127