Impact of harvesting time and postharvest ripening duration on the seed quality of Solanum melongena L. (eggplant)

The best harvesting stage of eggplant (Solanum melongena L.) to obtain quality seeds has not been given due attention under local seed production programs. The present practice is to allow fruits to ripen on the plant, however, it is believed that it may result in fewer fruits and low-quality seeds. Therefore, an experiment was conducted to identify the best maturity stage and the effect of postharvest ripening on the quality of eggplant seeds. Two eggplant varieties; Thinnavelli purple and Padagoda were grown and fruits were harvested at 35, 42 and 49 days after pollination (DAP) to determine the optimum harvesting time. Three postharvest ripening (PHR) periods (0, 1 and 2 weeks after harvesting) were also employed. Seeds from the fruits harvested at 35 DAP showed less germination %, vigour index and longer duration for 50% germination (T50). Germination percentage was increased up to 89% (Thinnavelli purple) and 72% (Padagoda) in seeds from fruits harvested at 35 DAP followed by 2 weeks PHR duration. Moreover, T50 was decreased from 1.74 to 0.94 days in Thinnavelli purple. The assessed seed quality parameters were much poorer in seeds from fruits harvested at 42 and 49 DAP. The results revealed that postharvest ripening enhances the seed quality of eggplant when fruits are harvested at the early ripened stage.