Treatment with Melatonin and Titanium Oxide Nanoparticles Improves Limiting Sodium Uptake in Broad Beans Under Salt Stress

Abstract

Abstract Agriculture serves as the fundamental support system for any growing nation. Broad beans are the predominant staple food crop in many countries, among various other crops. Various abiotic stressors, including waterlogging and salt, negatively impact the quality and quantity of broad beans. Salt stress is a significant limiting factor affecting broad beans’ physical, physiological, and biochemical characteristics. This study aimed to assess the impact of melatonin and titanium oxide nanoparticles (TiO 2 NPs) on the morphology and physiochemical properties of broad beans in relation to salt. Multiple concentrations of melatonin (50, 100 µM) and TiO 2 NPs (40 and 80 mM) and salt solutions (NaCl) (75 and 150 mM) were applied. At both degrees of salinity, which measure morphological features, osmotic and water potential, chlorophyll content, photosynthetic characteristics, total phenolic levels, proline levels, superoxide dismutase (SOD) activity and malondialdehyde (MDA) content. The results of our study indicate that the crucial role of melatonin and TiO 2 NPs in mitigating salt stress is due to the upregulation of transcription levels of genes that encode antioxidant enzymes and the modification of nutrient absorption. Melatonin and TiO 2 NPs effectively decrease the accumulation of Na in plant tissues. Boosting the transcription levels of antioxidant enzyme genes is achieved by the phosphorus (P), potassium (K), and nitrogen (N) assembly. Hence, our findings provide significant suggestions for optimizing the agricultural practices of these plants by using low-quality water with a concentration of 40 mM TiO 2 NPs.