Physiological, Biochemical and Molecular Changes in Relation to Different Storage Conditions and Accelerated Ageing in Bitter Gourd(Momordica charantia L.) cv. Punjab 14 Seeds

Bitter gourd (Momordica charantia L.) cv. Punjab 14 seeds harvested in mid-June were subjected to three post-harvest storage procedures, viz., fresh seeds (stored in refrigerator at 5ºC and 30% RH for 8 months), stored seeds (kept at roomtemperature for 8 months) and accelerated aged seeds. Fresh seeds stored in refrigerator were subjected to acceleratedageing (45ºC; 90% RH) for 3, 6 and 9 days, respectively. Our results showed that increasing ageing duration resulted inreduction in germination percentage and seedling vigour index. All the ageing treatments resulted in membrane damage, as indicated by solute leakage. Besides physiological changes, biochemical changes due to ageing included a reduction incontent of total soluble proteins whereas, the total soluble sugars and total free amino acids increased with acceleratedageing. There was a decrease in the activities of antioxidant related enzymes, viz., catalase and peroxidase. Exceptionally, -amylase activity increased with accelerated ageing. The amount of ascorbic acid, α-tocopherol and DNA also reducedwith accelerated ageing. Protein profile (SDS-PAGE) of aged seeds showed alteration in banding pattern when comparedto that of fresh seeds.