Exploring the interaction between vermicompost application and soil types on the dispersal of antibiotic resistome above- and belowground

Abstract

Antibiotic resistance genes (ARGs) enter the human body through raw edible vegetables, posing a growing threat to public health. However, the influence of vermicompost on ARG migration within soil–vegetable systems, along with its relationship to soil types, remains largely unexplored. Herein, a microcosm experiment was used to explore the migration of antibiotic resistome in soil-vegetable systems under vermicompost application with four typical types of soil, including black, brown, red, and chestnut, using leafy plants (Lactuca sativa) as a model. The results showed that vermicompost facilitated the disparity in ARGs and bacterial communities across different soil–vegetable systems, while soil type played a decisive role in determining the risk of ARG spread. Under vermicompost application, ARGs displayed the highest migration potential to leaf endophytes in red soil, with an exogenous bioaccumulation factor (EBAF) of 25.36. In brown soil, the EBAF of ARGs in leaf endophytes was only 12.21, while inhibiting the migration of ARGs to edible leaves. Vermicompost regulated ARG dispersal both above- and belowground across different soil types by increasing microbial interactions and increasing network complexity during community coalescence in the soil–vegetable system. This study highlighted the increased health risk associated with red soil compared to other soil types and identified brown soil as the most suitable for vermicompost application.