The impact of straw-returning methods on the transfer of ARGs in soil-plant systems and environmental risks

Recent years have seen significant advances in understanding the fate of antibiotic resistance genes (ARGs) in agricultural ecosystems. Various plant species show marked differences in accumulating ARGs in soil, closely linked to their traits and associated changes in soil microbial communities. Straw is a crucial agricultural byproduct, and its utilization plays a key role in sustainable agricultural development. However, the effects of different straw-return methods on the migration and accumulation of ARGs in the soil-plant system remain poorly studied. Returning straw to fields can alter ARG accumulation in plants through modifications to soil microbial community structure and physicochemical properties. Specifically, mulching using crushed straw can mitigate the risk of ARGs spread through elevating soil organic matter (SOM) content and improving soil structure. Meanwhile, straw composting can reduce ARGs accumulation by degrading antibiotic residues and altering microbial communities composition. This review synthesizes how straw-return methods alter soil environments and ARG transport in soil-plant systems. This study examines the mechanisms underlying ARG promotion and dissipation through straw-return methods, proposing strategies to identify cost-effective and environmentally sustainable approaches for reducing soil ARG residues while enhancing crop productivity. Future research should further optimize straw-returning technologies, integrate regional characteristics, and formulate rational straw management strategies to minimize the environmental risks of ARGs and facilitate sustainable agricultural development.