Physiological Response of Black Gram [Vigna mungo (L.) Hepper] Grown on Fly Ash-Amended Soil: Growth, Photosynthesis, and Antioxidant Defense

Abstract

The present study deals with the growth, photosynthesis, antioxidant defense along with the metal accumulation in black gram [Vigna mungo (L.) Hepper] grown on various combination of fly ash amended garden soil. Significant improvement of soil quality such as pH, nitrogen and organic carbon was observed in 25% of fly ash amendments. Besides, the bioaccumulation of Fe, Cu, Mn, and Zn was remarkably increased with the increase of fly ash in amended soil. Fly ash (25%) amended with garden soil led to a 62% increase in plant biomass. Photosynthetic rate, stomatal conductance, and chlorophyll content significantly increased under 25% fly ash amendments soil, though photosystem (PS) II activity remained unchanged compared to the plants grown in garden soil. Furthermore, the activity of some antioxidant enzymes such as superoxide dismutase, ascorbate peroxidase, and guaiacol peroxidase was increased over control under different fly ash amendments. Taken together, garden soil amended with 25% of fly ash not only improved the physicochemical properties of the soil but also contributed to better growth and photosynthesis in black gram.