Effect of anaerobic seed acclimation on the growth of eggplant (Solanum melongena L.) under waterlogged conditions

At seed and seedling phases, seeds were subjected to four anaerobiosis treatments,namely: A1-control (24h-imbibition before sowing), 24-h, 36-h, and 48-h anaerobiosis before sowing for A2, A3, and A4, respectively. Treated seeds were then germinated at two planting conditions, i.e.. normal (control) and waterlogged conditions. At the growth phase, acclimated seeds were germinated and then a 1-wk-old seedling was transferred in a 200-mL plastic cup with sterile soil inside the greenhouse. Two weeks after transplanting, they were subjected to normal or 10 days of waterlogged conditions. After that plants were maintained in a 5-L plastic bag containing sterile soil until fruit production. All treatments in both phases had three replications and were arranged in a randomized complete block design factorial design. At seed and seedling phases, the electrolyte leakage and the activity of alcohol dehydrogenase (ADH) enzyme were significantly affected by anaerobiosis treatments. The treatment decreased 60-80% of the leakage, but increased enzyme activity by 120%. The ADH activity of petridish-grown seedlings was higher than the nursery-grown. The banding pattern of total soluble proteins in dry and treated seeds had more intense bands than treated seeds, especially at MW67 and 14.4 kDa. After 1 wk of waterlogging, the 36 and 48-h anaerobiosis-treated seeds exhibited a modification of the protein profile. In terms of seed germination, the treated seeds under waterlogged conditions decreased by about 95% after 1 wk. At the growth phase, root ADH activity increased by 10, 30, and 60% during 1, 5, and 10 days of waterlogging, respectively. At the same time, plant relative water content (RWC) was reduced significantly by 8.4% over the control at the end of the treatment. Some changes occurred in the root protein profile under waterlogged conditions. Low molecular weight proteins below 14 kDa were attenuated, while proteins with sizes ranging from 20 to 45 kDa were more pronounced in treated samples than in the normal. Waterlogging induced ethylene production but decreased plant respiration rate and plant dry weight. At the productive phase, both total production and number of fruits/plant were not affected by all treatments. Total production and fruit number/plant were 404.6 and 351.1 g and 6.6 and 6.1 in plants from normal and waterlogged conditions, respectively