Preharvest Treatments to Enhance “Keitt” Mangoes Ripening and to Extend Their Shelf Life
Mango fruit growers and producers have been facing many major problems that influence the yield, quality and shelf life. In this study, a new approach was followed to achieve the balance between reducing fruit abscission, improving fruit quality especially coloration while enhancing the harvested mangoes shelf life. This research was carried out in a private orchard at Wady El- Natroun region, Beheira governorate, Egypt using “Keitt” mango trees during the two successive seasons 2016 and 2017. In addition to the control (water spray), eight more treatments were used which included: lysophosphatidylethanolamine (LPE) at 400 or 800 ppm, Ethrel at either 50 or 100 ppm and the combinations of these concentrations of LPE preceded Ethrel. In case of spraying various combinations, LPE spray preceded Ethrel spray by 2 hours. With all treatments, the surfactant Tween- 20 was added at 0.05% (v / v) and the spray was done by using a hand sprayer to the run off point. At harvest, the results revealed that LPE whether at 400 or 800 ppm was able to mitigate the adverse effect of Ethrel (at 50 or 100 ppm) on fruit abscission as compared with the sole application of Ethrel. In a similar manner, the shelf life assessment proved that weight loss was significantly reduced by the combined application of LPE followed by Ethrel at all used concentrations when compared with Ethrel alone. In addition, the combination treatments especially LPE at 800 followed by Ethrel at 50 ppm were able to retard the loss of pulp firmness. Meanwhile, carotene contents in the pulp and peel (skin) were significantly increased by Ethrel concentrations alone and by the combinations of LPE (at 800 ppm) preceded Ethrel at 50 or 100 ppm in both seasons. The least electrolyte leakage was obtained with the same above combinations while the greatest electrolyte leakage was obtained with the individual application of Ethrel at 50 or 100 ppm in both seasons. The outcomes of this study recommend spraying “Keitt” mango with a combination that included LPE at 800 ppm followed by Ethrel 50 ppm to overcome many production problems and to prolong the shelf life of fruits.