This study was carried out during two successive seasons (2016 and 2017) on six years old Keitt mango trees grafted on Succary seedlings as rootstocks and planted at 2×3 meters in sandy soil under drip irrigation system in Kafr El-Sohbi village, Qalubia Governorate, Egypt., To study the influence of kaolin and screen duo foliar application on fruit sunburn, yield and fruit quality. Hence, the foliar applications treatment were kaolin (aluminum silicate) at 25,50 and 75g/L and screen duo at 6,12 and 18 cm 3 /L sprayed once at mid of June and also sprayed twice at mid of both June and July during both seasons of study as well as, control (tap water spray). The influence was evaluated through the response of the different measurements as yield, sunburned fruit measurements, fruit quality and fruit skin color parameters with kaolin and screen duo concentrations and times of spray (once or twice). The obtained results revealed that the response to screen duo was more pronounced and differences between its three concentrations were significant in most cases as compared each other from one hand and the highest one (18 cm 3 /L.) was the most effective in most cases from the other hand. Referring the specific effect of times of spray (once or twice) data display obviously that the highest values in most cases were significantly in concomitant to fruits sprayed twice during both seasons of study. Anyhow, it could be concluded that, spraying screen duo at 12 and/or 18 cm 3 /L twice in summer months (at mid of both June and July) had a positive effect to prevent fruit sunburn damage and improved yield and fruit quality of Keitt mango fruits.

Guava is a nutritious fruit that has perishable behavior during storage. We aimed to determine the influences of some edible coatings (namely, cactus pear stem (10%), moringa (10%), and henna leaf (3%) extracts incorporated with gum Arabic (10%)), on the guava fruits’ properties when stored under ambient and refrigeration temperatures for 7, 14, and 21 days. The results revealed that the coating with gum Arabic (10%) only, or combined with the natural plant extracts, exhibited a significant reduction in weight loss, decay, and rot ratio. Meanwhile, there were notable increases in marketability. Moreover, among all tested treatments, the application of gum Arabic (10%) + moringa extract (10%) was the superior treatment for most studied parameters, and exhibited for the highest values for maintaining firmness, total soluble solids, total sugars, and total antioxidant activity. Overall, it was suggested that coating guava with 10% gum Arabic combined with other plant extracts could maintain the postharvest storage quality of the cold-storage guava.

Iron (Fe) is required for most metabolic processes, including DNA synthesis, respiration, photosynthesis, and chlorophyll biosynthesis; however, Fe deficiency is common in arid regions, necessitating additional research to determine the most efficient form of absorbance. Nano-fertilizers have characteristics that are not found in their traditional equivalents. This research was implemented on Washington navel orange trees (Citrus sinensis L. Osbeck) to investigate the effect of three iron forms—nano (Fe-NPs), sulfate (FeSO4), and chelated (Fe-chelated)—as a foliar spray on the growth, fruiting aspects, and nutritional status of these trees compared to control. The highest values of the tested parameters were reported when the highest Fe-NPs level and the highest Fe-chelated (EDTA) rate were used. Results obtained here showed that the spraying of the Washington navel orange trees grown under similar environmental conditions and horticulture practices adopted in the current experiment with Fe-NPs (nanoform) and/or Fe-chelated (EDTA) at 0.1% is a beneficial application for enhancing vegetative growth, flower set, tree nutritional status, and fruit production and quality. Application of Fe-NPs and Fe-chelated (EDTA, 0.1%) increased yield by 32.0% and 25% and total soluble solids (TSS) by 18.5% and 17.0%, respectively, compared with control. Spraying Washington navel orange trees with nano and chelated iron could be considered a significant way to improve vegetative growth, fruit production, quality, and nutritional status while also being environmentally preferred in the arid regions.