Inhibitory impact of MgO nanoparticles on oxidative stress and other physiological attributes of spinach plant grown under field condition.

ABSTRACT

Green synthesis of NPs is preferred due to its eco-friendly procedures and non-toxic end products. However, unintentional release of NPs can lead to environmental pollution affecting living organisms including plants. NPs accumulation in soil can affect the agricultural sustainability and crop production. In this context, we report the morphological and biochemical response of spinach nanoprimed with MgO-NPs at concentrations, 10, 50, 100, and 150 µg/ml. Nanopriming reduced the spinach root length by 14-26%, as a result a reduction of 20-74% in the length of spinach shoots was observed. The decreased spinach shoot length inhibited the chlorophyll accumulation by 21-55%, thus reducing the accumulation of carbohydrates and yield by 46 and 49%, respectively. The reduced utilization of the total absorbed light further enhanced ROS generation and oxidative stress by 32%, thus significantly altering their antioxidant system. Additionally, a significant variation in the accumulation of flavonoid pathway downstream metabolites myricitin, rutin, kaempferol-3 glycoside, and quercitin was also revealed on MgO-NPs nanopriming. Additionally, NPs enhanced the protein levels of spinach probably as an osmoprotectant to regulate the oxidative stress. However, increased protein precipitable tannins and enhanced oxidative stress reduced the protein digestibility and solubility. Overall, MgO-NPs mediated oxidative stress negatively affected the growth, development, and yield of spinach in fields in a concentration dependent manner. Supplementary Information The online version contains supplementary material available at 10.1007/s12298-023-01391-9.