THE effect of gibberellic acid (GA3), naphthalene ascetic acid ……(NAA) , benzyl adenine (BA) and salicylic acid (SA) at different concentrations on bunch weight, fruit quality and harvest date of date palms (Tamr cv.) was studied for two successive seasons (2013 & 2014) at a commercial orchard in Dakhla oasis, El-Wady El-Gadid Governorate, Egypt . In general, all treatments significantly increased the bunch weight and fruit physical properties as compared with control. Best results were achieved by GA3 at 150 ppm followed by NAA at 150 ppm when sprayed two times (at 4 and 8 weeks after pollination), represented in increasing bunch weight, fruit weight and dimension and flesh weight percentage with high content of TSS, reducing sugars and total sugars. While the lowest fruit content of TSS, total and reducing sugars were obtained with SA application as compared with other treatments or untreated one (control). On the other hand all tested growth regulators delayed harvesting. Tamr dates were harvested with a delay between 5 and 23 days when bunches sprayed with BA and NAA, respectively
Thus, the most beneficial treatment in this trial concern is GA
3 at 150 ppm, 4 and 8 weeks after pollination, which produced heaviest bunch weight and high fruit weight and dimensions and flesh weight percentage with high content of TSS, total and reducing sugars (which meaning high fruit quality) and could be considered as a recommended treatment under the conditions of this experiment.