Cadmium (Cd) contamination in paddy systems poses significant risks to environmental quality and food safety. Selenium nanoparticles (Se NPs) are increasingly explored as eco-friendly amendments to mitigate Cd accumulation in rice ( Oryza sativa L.), yet the influence of particle size on their effectiveness remains unclear. This study examined hydroponically grown rice seedlings exposed to Cd and treated with Se NPs of 50, 100, and 200 nm (1 mg/L Se), combining ultrastructural observations with transcriptomic, proteomic, and metabolomic analyses. Among the three particle sizes, the 100 nm treatment showed a relatively favorable balance between growth promotion and Cd reduction, increasing fresh biomass by 25.40% and reducing shoot Cd accumulation by 26.24% compared with the Cd treatment. Smaller Se NPs were associated with enhanced glutathione metabolism and jasmonic acid biosynthesis, which may help reduce Cd uptake, whereas larger Se NPs were linked to higher peroxidase activity, increased gibberellin biosynthesis, and upregulation of defense-related genes, indicating improved stress tolerance. Root-zone metabolomic profiling suggested that Se NPs may affect sulfur- and selenium-related metabolic responses under Cd stress. Overall, these results provide evidence of size-dependent modulation of Cd uptake and stress responses in rice, highlighting the potential of Se NPs to support environmentally sustainable strategies for reducing Cd bioavailability and mitigating contamination risks in agricultural hydroponic systems.
Zhang et al. (Mon,) studied this question.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: