The effect of periodic water stress and fertilizer applications on vegetati̇ve and generati̇ve evolution in Hacihaliloglu apricot variety

This study was conducted in 2018 and 2019 in order to determine the effects of water stress applied to a different group for each irrigation period and different doses of base fertilizers on plant growth, fruit yield and quality criteria on trees belonging to the five-year-old Hacıhaliloğlu apricot variety. Institute Directorate was conducted in Akçadağ-Karapınar Campus Research Application Garden. In the experimental area, 54 apricot trees with close development levels were marked from the apricot trees of the Hacıhaliloğlu variety, which were planted at 10x10 meters intervals in 2013. Water stress was applied to trees belonging to 5 different irrigation subjects (S1, S2, S3, S4, and S5) randomly selected from marked trees in 5 different irrigation periods in 3 repetitions, and water was given to the control (S6) subject in all these periods. In addition, three different doses of base fertilizer (15-15-15 N, P, K) were applied to all test trees at the beginning of spring. Phenological phases such as flowering periods, harvest dates and leaf fall times of the tested trees in 2018 and 2019 were followed and their dates were recorded In the samples taken from the fruits harvested at the harvest, pomological measurements were made in both years and the quality criteria in the fruit were examined and the total yields of the trees were recorded. In both years of the study, the effects of the applications on the phenological periods were found to be insignificant. In morphological measurements; while the effect of practices on stem and major diameter in both years was found to be insignificant in general, it was determined that G3 fertilization and control irrigation practices provided more improvement in annual shoot development. In physical measurements of fruits; it was determined that control and S4 irrigation practices increased fruit weight, while there was no significant difference in fertilizer applications. It was determined that S1 application in chemical measurements increased the SÇKM value in the first year of the experiment. In the study, the highest yield per tree was achieved with the G2 fertilizer dose for S1 irrigation in the first year, and G1 fertilizer dose for S5 irrigation in the second year. At the end of the study; It has been observed that fertilization increases the total yield, but the dose increase does not have a significant effect. The dose of G1 (900 g tree-1 NPK-15-15-15), which has a similar effect to other fertilization doses for tree growth, has been found to be recommended. It has been observed that S1 application in water stress periods stands out compared to other water stress issues, does not cause significant yield and fruit quality losses, and has been determined as a recommended water stress strategy for apricot. KEYWORDS: Apricot, Prunus armeniaca, Fertilization, Irrigation, Periodic Water Stress