Role of Plant Growth Regulators and Biological, Chemical, Nutrient, and Nanomaterial-Based Approaches in Mitigating Micro- and Nanoplastic Stress in Agroecosystems.

Micro- and nanoplastics (MNPs) are emerging pollutants in agricultural ecosystems, accumulating in soils and adversely affecting plant growth and crop yields. Although their toxicity is increasingly reported, the role of stress mitigators in reducing MNPs-induced toxicity in soil-plant systems remains insufficiently summarized. This review evaluates current research on mitigation strategies, including nanoparticles, phytohormones, biochar, chemicals, nutrients, plant growth-promoting bacteria and rhizobacteria, fungi, and signaling molecules. Evidence shows that these mitigators can reduce MNPs-induced stress by improving rhizosphere microbial communities, increasing plant growth and photosynthetic efficiency, and regulating biochemical, transcriptomic, and metabolomic responses. In addition, important tolerance pathways and mechanisms influenced by these mitigators are also discussed. The review highlights major knowledge gaps in existing studies and proposes future research directions. Overall, it provides a concise framework to guide the development of effective mitigation approaches to address MNPs contamination and improve sustainable crop production under emerging environmental stress conditions.