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.

In this experiment, ten-years-old "Flame Seedless" grapevines at El-Nubaria region, Behira governorate, Egypt, were preharvest sprayed during 2016 and 2017 seasons with water only with surfactant (control), 400 mg/ L ethephon, 100 mg/ L ProTone (active ingredient of Abscisic acid 10%), 100 mg / L methionine, 400 mg/ L oleic acid, ProTone plus methionine, ProTone plus oleic acid and ProTone plus methionine and oleic acid, in order to investigate their influence on berry coloration, berry quality of grapes and the possibility of using these materials as alternatives to ethephon treatment. The results revealed that ethephon, ProTone, methionine and oleic acid-treated grapes increased berry anthocyanin contents, TSS and decreased berry acidity and chlorophylls. On the other hand, the formulation containing ProTone, methionine and oleic acid possessed higher anthocyanin contents and reduced berry shattering in addition to weight loss percentage as compared with ethephon and control treatments. This study recommended using the formulation containing ProTone plus methionine and oleic acid at véraison (10-15% berry coloration) as an alternative to ethephon treatment for enhancing berry coloration, berry quality and overcome some adverse effects of ethephon such as increased berry shattering and berry weight loss, which reflects on berry appearance.

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Few attempts have been made to overcome problem of the soft scald. Many factors and conditions are associated with such physiological disorder. In this study, seven-years-old "Anna" apple trees were preharvest sprayed during 2016 and 2017 growing seasons with lisophos 1000mg/ litre, potassium sulphate 2%, calcium sulphate 2% and their combinations in order to investigate their influence on initiation of the soft scald and fruit quality especially fruit coloration at harvest as well as keeping fruit quality during storage for seven days on refrigerator. Lisophos alone or plus either calcium sulphate or potassium sulphate reduced initiation of the soft scald at harvest as compared with untreated fruits, in addition to retarding the loss of fruit firmness. The application of potassium sulphate alone or incorporated with lisophos treatment increased fruit diameter, fruit TSS, total sugars, peel anthocyanin and carotene contents but decreased fruit acidity, peel chlorophyll a and b as compared with control. After seven days of refrigerated shelf life, the application of lisophos plus calcium sulphate retarding the loss of flesh firmness, reduced weight loss% and incidence of the soft scald percentage. This study provided evidences about the possibility of reducing incidence of the soft scald in "Anna" apples by preharvest application of lisophos plus either calcium sulphate or potassium sulphate, while, enhancing fruit quality and coloration.

The present experiment was conducted on six-years-old "Keitt" mango trees at El-Bostan region, El-Behira governorate, Egypt to study the effect of 4-chlorophenoxyacetic acid (4-CPA) and brassinosteriods (BR) on fruit set, yield and quality of "Keitt" mangos. The following seven treatments were used, control, brassinoloide at 1 mg/L, brassinoloide at 2 mg/L, 4-chlorophenoxyacetic acid at 10 mg/L, 4-chlorophenoxyacetic acid at 20 mg/L, brassinoloide at 1 mg/L + 4-chlorophenoxyacetic acid at 10 mg/L and brassinoloide at 2 mg/L + 4chlorophenoxyacetic acid at 20 mg/L. The treatments were applied twice at full bloom and after fruit set with ten days. The results showed that pre-harvest application of 2 mg/L brassinoloide increased fruit set, fruit retention, yield, average fruit weight, average fruit size and ascorbic acid. Pre-harvest applications of 4-chlorophenoxyacetic acid either at 10 mg/L or 20 mg/L increased fruit set, retention, yield, fruit weight, size, fruit firmness and ascorbic acid. The formulation containing 4-chlorophenoxyacetic acid plus brassinoloide either at low concentration or high concentration enhanced fruit set, yield, firmness, fruit physical and chemical quality of "Keitt" mangos fruit.