Effect of ultraviolet-B radiation on biomass production, lipid peroxidation, reactive oxygen species, and antioxidants in Withania somnifera

Abstract

The present study was aimed at understanding the effects of long term supplemental UV-B (3.6 kJ m-2 d-1) on biomass production, accumulation of reactive oxygen species, lipid peroxidation, and enzymatic antioxidants in leaves and roots of Withania somnifera (an indigenous medicinal plant). Under the UV-B treatment, a reduction in biomass and an increased malondialdehyde content (a characteristic of lipid peroxidation) were observed in both the shoots and roots. Amongst ROS, H2O2 content increased under UV-B in the leaves, whereas it decreased in the roots, and superoxide radical production rate decreased in both the plant parts. The activities of all enzymatic antioxidants tested (ascorbate peroxidase, catalase, glutathione reductase, peroxidase, polyphenol oxidase, and superoxide dismutase) increased under the UV-B treatment, the increase being greater in the roots.