Irrigation Regimes for Apricot Trees under Different Rates of Soil Moisture Depletion

Document Type : Original Article

Abstract

 THIS EXPERIMENT was conducted at El-Kanater Horticultural Research Station, Kalubeia governorate through two successive seasons of 2010 and 2011 to study the effect of irrigation at 20, 40, 60 and 80% depletion from the available soil moisture on some water relations, some vegetative growth characteristics, yield, fruit quality and N, P, K, Fe, Zn and Mn leaf contents of twelve years old " Canino" cultivar apricot. Trees grown on clay loamy soil and planted at 5 x 5 meters apart. The results revealed that; consumptive use increased by decreasing the available soil moisture depletion (at high soil moisture). The monthly water consumptive was low after dormancy, then increased to reach the maximum during July and August and declined to minimum during October. The value of calculated crop coefficient (Kc) was 0.71.
Moreover, The value of water use efficiency (WUE) was higher with irrigation at 40% depletion of available soil moisture (1.21 and 1.33) compared with (0.98 and 0.97) obtained from irrigation at 80% depletion from available soil moisture during the two growing seasons, respectively. Vegetative growth (shoot length, shoot diameter and leaf area), fruiting parameters (fruit set percentage and yield) and fruit properties (fruit firmness, TSS and TSS/acid ratio) scored the highest significant values with irrigation at 20% and 40% depletion from the available soil moisture. While the leaf content of N, P, K, Fe and Zn significantly decreased when irrigation rate reduced.