Role of zinc oxide nanoparticles on phytostabilization efficacy of <i>Raphanus sativus</i> for cadmium polluted soil under microplastic stress

The accumulation of Cadmium (Cd) and microplastics (MPs) in agricultural soils poses a serious threat to plant growth, crop productivity, and food safety. This study investigates the combined effect of Cd and MPs on growth, antioxidant enzymes, and lipid peroxidation of Raphanus sativus, as well as the potential of Zinc oxide nanoparticles (ZnO NPs) in alleviating the combined Cd and MPs stress. Seeds were primed with different doses of ZnO NPs (40, 80, and 160 mg L−1). The findings depicted that MPs and Cd significantly reduced the growth attributes and photosynthetic pigments, while increasing the oxidative stress markers, biochemical content, and antioxidant activity in R. sativus. In contrast, ZnO NPs application improved growth attributes, photosynthetic efficiency, and antioxidant enzymes activity of R. sativus. Seed priming with ZnO NPs (160 mg L−1) showed significant improvement in growth and physiological attributes while reducing oxidative stress and Cd accumulation in radish plant tissues. These findings indicate that ZnO NPs application enhances plant tolerance to combined Cd and MP stress by improving the antioxidant defense system and reducing Cd uptake. Therefore, ZnO NPs seed priming represents a promising strategy for enhancing crop resilience and promoting sustainable agricultural practices in multi-contaminated soil.