Physiological and Biochemical Processes in the Exogenous Administration of Selenium Nanoparticles and Selenium/Copper Oxide Nanocomposite to Reduce Salt Stress in Zea mays L.

Abstract

Research on nanoparticles (NPs) is gaining increasing popularity as a way to enhance abiotic stress tolerance and improve crop productivity. This study assessed the effects of foliar spray of selenium NPs (Se NPs) and selenium/copper oxide nanoparticles (Se/CuO NPs) at 50 and 100 ppm on the growth and biochemical characteristics of Zea mays L. plants grown under saline stress conditions (100 mM). Se NPs and Se/CuO NPs were analyzed by energy dispersive X-ray, transmission electron microscopy, and Fourier transform infrared spectroscopy analyses. The Se NPs and Se/CuO NPs were found to have an average particle size of 135.2 and 75.1 nm using the ImageJ tool.  Shoot and root lengths, chlorophyll levels, protein, phenols, and flavonoids were all investigated in this study. Plant growth and chlorophyll concentration dropped under salt stress but were improved with the application of Se and Se/CuO NPs. The enzymes catalase, superoxide dismutase, and glutathione reductase exhibited the highest values at 100 ppm of Se/CuO NPs, of 74.4, 132.1, and 43.2 mmol/g, respectively. Se and Se/CuO NPs reduced stress and increased chlorophyll. ZnO-NPs improved maize plants' resistance to the unfavorable effects of saline soils. Finally, plant metabolism and abiotic stress tolerance were improved by Se and Se/CuO NPs.