Selenium nano bio-enrichment of mung bean (Vigna radiata L.): Impacts on physiological characteristics and seed quality at the greenhouse and semi-natural conditions

Abstract

Selenium (Se) biofortification, as an important strategy to reduce hidden hunger levels by increasing the nutritional quality of crops, has been previously investigated in very few studies. This research aimed to understand how selenium nanoparticles (SeNP) affect the growth and physiological parameters of the mung bean plants (Vigna radiata L.) and the selenium biofortification of mung bean seeds. Plants grown in greenhouse and semi-natural conditions were sprayed with SeNP at concentrations of 25, 50, and 75 mg/L, 48 and 43 days after planting. In the greenhouse conditions, 94 days after germination, intracellular changes, antioxidant enzymes, photosynthetic pigments, and biomass were evaluated. In semi-natural conditions, the effects of SeNP on the yield and quality of mung beans were determined. In the greenhouse, 25 and 50 mg/L concentrations significantly raised SOD activity by 26.9 % and 36.9 % compared with the control (p ≤ 0.05), but not in the semi-natural conditions. At 50 mg/L, the dry matter significantly increased in both conditions by 10 % compared with the control (p ≤ 0.05). Additionally, such concentration increased seed yield compared with the control (243 %; p ≤ 0.05). At 75 mg/L, plants grown in the greenhouse had the intracellular structure destroyed, reduced chlorophyll a and dry matter accumulation by 30.6 % and 15.9 % compared with the control (p ≤ 0.05). Conversely, there were no signs of stress under semi-natural conditions, and the dry matter and grain yield significantly enhanced compared with the control (p ≤ 0.05). The concentrations of 50 and 75 mg SeNP/L did not affect the levels of P and K in the grains; however, it resulted in a reduction in the amount of Fe and Zn while simultaneously increasing the Se content (by 629 and 1053 %; p ≤ 0.05). The results suggest that nano selenium application may be a promising option for Se enrichment of food supply for people with Se deficiency.