The Effect of Organic Fertilization on Olive Production and Quality of Olive Fruit and Oil for Irrigated Olive Cultivar Doebli

Abd Al-Kareem Jerdy
General Commission for Scientific Agricultural Research-
Homs Research Center
Tishreen University, Faculty of Agriculture


This study was conducted at Homs Research center, Al-Mokhtariah Research station Homs in order to observe the effect of organic fertilization on olive fruits and oil productivity of local cultivar (Doebli) in the years 2006- 2007.
This research includes five fertilization treatments as follows:
–    1st treatment: control (without fertilization).
–    2nd treatment: 20 m³/h, of organic fertilizer.
–    3rd treatment: 40 m³/h of organic fertilizer.
–    4th treatment: 60 m³/h of organic fertilizer.
–    5th treatment: only mineral fertilizers according to Ministry of Agriculture’s recommendations.
The results of this research indicate that treatments 3 and 4 were significantly higher than control at 5% level, in number of complete flowers, so the treatments 3, 4, 5, which were higher than control (without fertilization) in fruit set amount.
The amount of falling fruits in the first treatment (control) was much higher than the fourth treatment at the level 5 %, so that the production of the control treatment decreased, and productivity was high in the 4th treatment which exceeds other treatments at level 5 %, and this is caused by improvement of nutritional conditions, and abundance of nutrients to the plant in available formats.
Chemical analysis of oil after one year storage in nitrogen environment indicates that the oil was stable and that is no self-oxidation was occurred, in treatments 3 and 4 comparing with other treatments, where the peroxide values for these two treatments were 11.3- 11.6 mEq O2\kg respectively, and percentages of acidity were 0.32 % – 0.42 % respectively.
Absorbency at 270 nm wave length was less than 0.25 % and this responds to IOOC for olive oil.
Fatty acids (palmitic- stearic- palmitoeic- oleic – linoleic – linolenic) stay in their normal levels, and changes were at lower levels.
Obtained results from this study indicate positive impact of applying organic fertilization on olive trees, by means of getting high quality olive oil, so this is the new way in clean organic farming worldwide.