Mitigating the health risk of antibiotic resistance genes through reductive soil disinfestation in protected agroecosystems

Abstract

Soil used to grow vegetable crops is usually subjected to various soil management strategies. However, the effects of these management strategies on antibiotic resistance genes (ARGs), which have important implications for human health, are still poorly understood. Here, we examined the effects of reductive soil disinfestation (RSD) on soil ARG profiles, the composition of the bacterial community, and the interactions between ARG hosts and nonhosts in soils under different fertilization regimes. The results indicated that RSD treatment significantly decreased the relative abundance of soil ARGs and mobile genetic elements (MGEs) by 43.4 % to 61.3 %. During the following planting period, the RSD-treated soils were more susceptible to colonization by exogenous microorganisms from the composted chicken manure. Moreover, RSD treatment inhibited the transfer rate of ARGs from the soil to the plant root system and resulted in a lower proportion of ARG hosts with pathogenic ability. Notably, RSD treatment promoted cooperation among nonhost communities. The findings of our study indicated that RSD treatment significantly reduced the health risk of soil resistome. In summary, the application of RSD treatment effectively diminishes ARG pollution, thereby playing a crucial role in enhancing soil ecological health and advancing sustainable agricultural development.