Effects of artificial aging on physiological and biochemical characteristics of sesame seed

The germination index,malondialdehyde(MDA) content,and the activity of peroxidase(POD) and superoxide dismutase(SOD) were studied with black sesame(zhengzhi.4)seeds treated with high artificial aging.The results showed that germination potential,germination rate,germination index and vigor index were reduced gradually and the MDA content was raised with the aging seeds.The activity of POD and SOD decreased in aged seeds with extended treating time.The main mechanism for deterioration of sesame seeds during artificial aging was closely related to an increase of lipid peroxidation and a decrease in activity of antioxidant enzymes.The threshold for sesame seed viability was 80% artificial aging sesame seed germination potential whose decreasing tendency was consistent with POD activity,so POD activity may be an index to indicate the characteristic of height and loses of vigor in the seeds.