Evaluation of morphophysiological, biochemical and antioxidant activity of green gram (Vigna radiata (L.) R.Wilczek) in responses to gamma irradiation

Mutation breeding plays a vital role as a source of genetic diversity to im-prove plant growth and development. Green gram (Vigna radiata (L.) R. Wilczek) "Vamban 2" variety was selected for this investigation. The doses applied to the healthy seeds of green gram were 100 Gy, 200 Gy, 300 Gy, 400 Gy, 500 Gy, 600 Gy, 700 Gy and 800 Gy and non-treated seeds were kept as control throughout this study. A lethal dose (LD50) was observed at 500 Gy, whereas seedling length, fresh and dry weight decreased as the applied doses increased while compared to the control. Irradiated seed-lings showed a decreased content of chlorophyll a compared to Chloro-phyll b and increased carotenoid content compared to the control. Bio-chemical characteristics such as reducing sugar, starch, protein, amino acid and proline content were increased and noted maximum at 800 Gy. Antioxidants and lipid peroxidation (MDA) increased gradually along with increasing doses. FTIR analysis exhibited maximum functional groups at 600 Gy and ESR data showed ample hyperfine range of structure at 500 Gy, 600 Gy and 700 Gy. This investigation found considerable altera-tions in morphology, photosynthetic pigment, biochemical characteris-tics and antioxidant analyses, which suggest an idea to select an appro-priate dose of gamma irradiation in green gram for successive breeding programme.