Discussion
In addition to its xeromorphic leaf features, date palm displays true halophytic adaptations to salt stress probably more than many other fruit trees. Their growth and productivity, however, can be greatly reduced by salinity, aridity and nutrient deficiency. Such conditions might disturb osmotic pressure, ionic imbalance, nutrient uptake, and photosynthetic apparatus of trees and, therefore, affect various physiological and biochemical mechanisms related with tree growth, productivity and fruit quality. Thus, optimizing the fertilization program is critically required to improve growth and increase yield of date palms under harsh conditions. In the current experiment, the effects of fertigation at different rates vs. conventional soil broadcast on palm growth, fruit set, yield, fruit quality and nutrient uptake of tissue culture-regenerated young ‘Barhee’ palms grown in sandy loam calcareous soil as an attempt to enhance new orchard establishment