Green Synthesized Se Nanoparticle-mediated Alleviation of Salt Stress in Field Mustard TS-36 Variety

During this decade, selenium nanoparticles have been found to play a crucial role in helping plants endure several stress conditions, which thereby helps enhance the production of crops in such harsh environments. Globally, high salinity is considered a long-term stress in the crop fields which affects the growth and production of many crops, including mustard—one of the most important oil crops. Here, the activities of spherical-shaped selenium nanoparticles with an average particle size of 55.81nm, synthesized and functionalized by phytochemicals of fresh grape aqueous extract, were evaluated in the salinity stress (200mM NaCl) tolerance of mustard plants grown hydroponically in modified Hoagland’s solution. These bioactive nanoparticles (30mg/L) have exhibited significant activity in alleviating the salt stress complications in mustard, enhancing the activities of antioxidant enzymes (SOD 41.20%, CAT 64.10%, APX 63.06%, and POX 70.43%), phenolic content (98.88%), flavonoid content (86.90%), and free radical scavenging activity (61.89%). The seed germination percentage, root and shoot length, fresh and dry weight per plant, water content percentage, chlorophyll content, carbohydrate content, and protein content were significantly improved by 39.66%, 75%, 60.64%, 41.2%, 22.11%, 1.02%, 81.92%, 24.65% and 79.14% respectively by the nano selenium application during NaCl stress compared to the control group growing under salt stress without nanoparticles. Gas chromatography-mass spectrometry chromatogram analysis inferred the interaction between the nano-selenium and mustard plants under salt stress. Besides, the in-silico analysis revealed the active molecular interactions between selenium and 20 different proteins of mustard, including glutathione peroxidase, an important antioxidant enzyme.