Physiological and Biochemical Response of Gamma Irradiated Sesamum indicum L. Seed Grown in Heavy Metal Contaminated Soil

This study was performed to assess the physiological and biochemical changes in Dry seeds of sesame exposed to different doses of gamma radiation (0.0, 10, 25, 50, 100 and 200 Gy) emitted from Co-60 and cultivated in heavy metal contaminated soil. Seed irradiation with gamma rays significantly affects photosynthetic pigment fractions, total free amino acids and soluble protein content. Also, accumulation of the reactive oxygen species such as hydrogen peroxide and malondialdehyde was observed as oxidative stress indicator. Moreover, increasing gamma doses improved the activity of enzymatic (superoxide dismutase, peroxidase and polyphenol oxidase) or non-enzymatic (total free proline, phenolic and flavonoid compounds) antioxidant. Ascorbic acid content in sesame plant was decreased in the control and irradiated plants with the elapse of time; also significantly and gradually decreased by increasing gamma dose from 0.0-200 Gy.