摘要

近几十年来，有机食品尤其是有机蔬菜的需求增长迅速。然而，通过有机生产程序向蔬菜引入更多抗生素抗性基因（ARG）和抗生素抗性细菌（ARB）的风险早已被忽视。在我们的研究中，通过使用高通量定量PCR和16sRNA Illumina测序技术，我们研究了常规（CPL）和有机生产的莴苣（OPL）中ARG和微生物群落的丰富性和多样性。在样品的叶绿素和叶内生菌中共检测到134种ARG。 OPL中的ARGs的绝对拷贝数在CPL中是8倍。我们还观察到OPL和CPL之间微生物群落的显着差异，以及OPL中叶内和叶内生细菌的多样性低于CPL。曼特尔试验和变异分配分析（VPA）表明ARGs的特征受细菌群落组成的强烈影响。 ARG和细菌类群之间的网络分析表明，八个细菌家族被认为是ARG的潜在寄主。这些结果提供了有机农业对蔬菜中细菌和ARG组分的影响的见解。

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