Effects of Different Irrigation Regimes on Vegetative Growth, Fruit Yield and Quality of Young Apple Trees

This study was carried out to investigate the effects of different irrigation regimes on the vegetative growth, fruit yield and quality of young apple trees from 2000 to 2007 year in Igdir Plain conditions. Irrigation regimes were applied by increasing the available water at 90 cm depth soil profile to field capacity in different time intervals (S1: 7 days, S2: 14 days, S3: 21 days and S4: 28 days). Three apple varieties grafted on MM106 rootstock (Golden Delicious, GD; Starking Delicious, SD; and Granny Smith, GS) and under-tree micro sprinkler irrigation method was used in this study. Effects of irrigation regimes on vegetative growth, fruit yield and quality were not statistically significant. Statistically significant differences were generally obtained among years, and cultivars. The average values of vegetative growth and fruit yield per tree of the GD (13.9 cm(2) year(-1) and 60.3 kg tree(-1)), fruit yield per unit trunk cross - sectional area of the GD and the SD (0.49 kg cm(-2) for both cultivars), and fruit yield per unit crown volume of the SD (7.4 kg m(-3)) were more than those of other cultivars for the experimental years. Titrable acidity and pulp hardness of the GS (1.18% and 6.3 kg cm(-2)), and total solids soluble in the water for the GD (12.2%) was more than other cultivars. The highest water use efficiency, and irrigation water use efficiency were obtained from the S4 irrigation regime for all the cultivars. Consequently, the S4 irrigation regime to have the highest water use efficiency should use to conserve the water for the cultivation of apple in Igdir Plain conditions.