Micron-engineered biochar mitigates antimony and microplastics toxicity by reshaping soil microbiome and plant...

Antimony (Sb) and microplastics (MPs) are environmental threats for plants and human health. Antimony is known to impair plant growth, but the combined effects of Sb and MPs on plant and soil traits remain unexplored. This study examined the role of micron-engineered biochar (MBC) in mitigating Sb (250 mg kg^-1) + MPs (1%) soil contamination. Five treatments were established in a pot experiment: control, Sb + MPs, Sb + MPs + MBC applied at 1%, 1.5% and 2%. MBC counteracted the negative impacts of Sb + MPs on leaf water status, osmo-regulating compounds (average, +57%), antioxidant activities (average, +93%), soil Sb content and plant uptake (both, -31%), soil nutrient (N, P, K) contents and plant uptake (average, +72%), and grain yield (+57%). MBC also increased the abundance of Acidobacteria, Actinobacteria, Bacteriodota, and Proteobacteria as well as antimony degrading genes. Transcriptomic analysis revealed that MBC supply mitigated Sb + MPs toxicity by upregulating the MAPK signaling cascade, ABC transporters, ion export channels, peroxisomes, ascorbic acid, aldehyde, and galactose metabolism. These findings suggest that MBC is a multidimensional resource for remediating co-contaminated soils and enhancing rice productivity.