The effect of existing irrigation program on yield and quality in mandarin orchard grown under mediterranean climate conditions

This study was conducted in a citrus orchard consisting of Nova and Satsuma mandarin varieties located in Karataş District of Adana Province in 2023. In the experiment, it was aimed to investigate the effect of the current irrigation program applied to the citrus orchard on the yield and quality of the mandarin varieties grown. Citrus orchard was irrigated with drip irrigation system. In the drip irrigation system used for irrigation, dripper flow rates were measured as 3 L h-1 for Nova mandarin and 2.5 L h-1 for Satsuma mandarin and dripper spacing was 0.90 m. In the experiment, drip irrigation laterals parallel to each other on both sides of the tree trunk were used. During the irrigation season, 325.14 mm and 253.32 mm irrigation water was applied to Nova and Satsuma mandarin varieties, respectively. Nova and Satsuma mandarin varieties yielded 75.75 kg/tree and 250 kg/tree, respectively. According to the results obtained, the average fruit weight of Nova mandarina variety was 154.87 g and the average fruit weight of Satsuma mandarina variety was 106.86 g. Accordingly, it was determined that the average fruit weight of Nova mandarin variety was approximately 48 g more than that of Satsuma mandarin variety. As a result of the independent group t test performed to determine whether there is a significant difference between the values of the Nova and Satsuma citrus variety pomological trait scale peel thickness sub-dimension, the difference between the mean peel thickness of the Nova variety 2.88 mm and the mean peel thickness of the Satsuma variety 3.08 mm was found statistically significant at 5% significance level. In the study, independent group t test analysis was performed to determine whether the differences in the number of slices, which is the sub-dimension of the pomological trait scale, according to the variables of Nova and Satsuma citrus varieties were significant. The mean number of slices was approximately 10 slices in Nova variety and 11 slices in Satsuma variety and this difference in favor of Satsuma was found to be statistically significant at 5% significance level. The difference between the water soluble dry matter content (WDSM) values obtained in Nova and Satsuma varieties was found significant at 5% significance level according to the independent group t test result. The average WDSM values were 12.25 and 11.42 for Nova and Satsuma cultivars, respectively.