Enantiomer-specific effects of tebuconazole on antibiotic resistance gene and potential spread across the soil-vegetable continuum.

Although pesticides can exert enantioselective effects on microbial communities in agroecosystems, their roles in shaping antibiotic resistance gene (ARG) dissemination across the soil-vegetation continuum remains poorly understood. Here, we investigated the effects of the R- and S-enantiomers of tebuconazole, one of the most widely used fungicides in the global market, on ARGs, mobile genetic elements (MGEs), bacterial communities, and potential pathogens across a soil-pak choi continuum. S-tebuconazole consistently had stronger effects than R-tebuconazole, increasing the ARG abundance across the soil-pak choi continuum by 7.59-76.95%. It further enhanced ARG-MGE associations, increased ARG host network complexity, and promoted shifts in the bacterial community structure accompanied by increased abundance and diversity of potentially pathogenic bacteria. Collectively, these findings reveal pronounced enantioselective effects of tebuconazole on ARG dissemination and microbial ecological risks, highlighting S-tebuconazole as a greater ecological concern.