Enhancing Coloration and Extending the Shelf Life of Plums While Alleviating Leaf Abscission by Utilizing Lisophosphatidylethanolamine and Oleic Acid

Abstract

Poor coloration of “Kelsey” plum fruits is considered one of the major problems that have been facing Egyptian growers, which hindered the expansion of “Kelsey” plum cultivation. Producers are in critical need to an effective treatment that enhances skin coloration while maintaining their keeping quality and their shelf life after harvest. Thus, the application of Ethrel, as an ethylene-releasing compound could increase anthocyanin content in plum skin. However, it has negative impact on leaf defoliation, yellowing in addition to its adverse effect on fruit storability. Thus, the objectives of this study were to enhance coloration of plums by using Ethrel before harvest in a new formulation to mitigate its damaging effects on leaves and fruits. Treatments included water as the control, Ethrel at 500 ppm alone or in a combination with either lisophos or oleic acid in addition to Ethrel plus both lisophos at 400 ppm and oleic acid at 400 ppm. Meanwhile, each of lisophos and oleic acid were applied individually. The results proved that the incorporation of both lisophos and oleic acid in one formulation with Ethrel mitigated the adverse effects of Ethrel on leaf abscission, leaf senescence and fruit shelf life and enhanced anthocyanin content in plums skin, in addition to prolonging their shelf life. Meanwhile, the incorporation of either lisophos or oleic acid to Ethrel resulted in greater anthocyanin content as compared with the control. Moreover, the formulation containing Ethrel plus both lisophos and oleic acid caused a significant increase in anthocyanin as compared with Ethrel alone or in the presence of either one of the two compounds. Furthermore, electrolyte leakage was significantly decreased in fruit tissue treated with Ethrel plus both lisophos and oleic acid. While lisophos alone resulted in the lowest percentage of such leakage of electrolytes in a consistent manner. In conclusion, this study provided an applicable solution to plum growers that could be adapted on a field scale to solve the problem of color enhancement without an associated leaf abscission or short shelf life by using Ethrel in a formulation containing lisophos and oleic acid.