Antioxidant Enzymes Activities of Walnut Nursery Trees to Drought Stress Progression

Authors : Fatma YILDIRIM, Meltem ESEN, Selçuk BİNİCİ, Civan ÇELİK, Adnan YILDIRIM, Yaşar KARAKURT

Pages : 217-225

View : 23 | Download : 12

Publication Date : 2021-12-28

Article Type : Research Paper

Abstract :This research was carried out to determine the biochemical responses of Chandler and Fernor walnut cultivars saplings grafted on the Juglans regia seedling rootstock under water stress in 2020. In accordance with this purpose; three different irrigation levels were applied to the one-year-old seedlings in polyethylene tubes in the greenhouse for three months: 1); full irrigation as control insert ignore into journalissuearticles values(100% of potted field capacity insert ignore into journalissuearticles values(PFC);); and 2); two different levels of restricted water application insert ignore into journalissuearticles values(50 and 25% of PFC);. The amount of decreasing water was provided every 5 days. The antioxidant enzyme activities including ascorbate peroxidase insert ignore into journalissuearticles values(APX);, catalase insert ignore into journalissuearticles values(CAT);, superoxide dismutase insert ignore into journalissuearticles values(SOD);, and peroxidase insert ignore into journalissuearticles values(POD); in the leaves were determined every 15 days. In terms of the properties examined, statistically significant differences were found between the applications in the all analysis periods. In general, as the severity and duration of the water stress increased, the antioxidant enzyme activities gradually increased and while the highest values were determined in the 25% PFC application, the lowest values were determined in the 100% PFC control application. As a result, the walnut saplings developed antioxidant defense mechanisms against water stress, demonstrating a possible tolerance. This suggests that the tolerance may be due to the activation of antioxidant systems and the reduction of oxidative damage. It has been determined that the antioxidant enzyme activities have different tendencies for both cultivars in response to the oxidative damage. While POD and CAT activities were at the higher levels in the Chandler cultivar; SOD and APX activities were at the higher levels in the Fernor cultivar.
Keywords : Juglans regia, Fernor, Chandler, Water stress, Enzyme