Effect of Fertigation on Fruit Yield, Oil Quality and Leaf Nutrients of Olive (Olea europaea L.) cv. Zard

In this study, the effects of fertigation with different levels of nitrogen (200, 400 and 600 g/tree and the ratio of nitrogen, phosphorus and potassium was 4: 1: 3) and hole method fertilization on flowering, fruit yield, oil yeild and quality of olive cultivar Zard were investigated during two consecutive years. The results showed that fertigation treatments significantly increased inflorescences and flowers number, fruit and oil yield. The highest number of inflorescences and flowers were found with 400 g nitrogen as compared to the control and hole method fertilization in the first year. The highest fruit yield (35.2 kg/tree) was found with 400 g nitrogen in the first year and 400g and 600g nitrogen about 44.65 kg/tree in the second year. The highest oil yield (4.5 kg/tree) was found with 400 g nitrogen in the first year and 600 (8 kg/tree) and 400 (7.2 kg/tree) g nitrogen in the second year, respectively. No significant differences were found between fertigation treatments and hole method fertilization and control for oil peroxide value, free fatty acids, K232. The highest leaf nitrogen and potassium contents were found in hole metod fertilization and fertigation with  200 g nitrogen, respectively. Overall, fertigation with 400 g/tree nitrogen could increase fruit and oil yeild in olive cultivar Zard withoud undiserable effects on oil qualiy.