The present investigation was carried out during 2010 and 2011 seasons on Hayany date palm cultivar grown at El-Arish, North Sinai Governorate, Egypt, and depended on rainfall for irrigation, to study the effect of using olive pomace alone (as organic fertilizer) or in combination with nitrogen, phosphorus and potassium fertilizers on yield, fruit quality and some minerals content in leaves. The results could be summarized as follows. Fertilizing with 25 Kg olive pomace combined with N or NP or

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... NK per palm tended to increase N content in pinnae as compared with other treatments. K content affected with the fertilization treatments, NK , 25 Kg olive pomace + NK and control treatments gave the highest of values leaf K content in both seasons. Moreover, P, Mg and Na content in pinnae were not significantly affected by different fertilization treatments including the control in both seasons. However Fe, Zn and Mn percentages were increased by adding olive pomace either alone or combined with mineral nutrients compared to other treatments. Concerning Ca content, no consistent trend was found between different treatments including the control. Moreover, adding olive pomace combined with NP and NK increased total chlorophyll in pinnae. As for the fruit chemical characteristics, no significant differences in TSS content in fruits were detected between different treatments including the control except treatment N which gave the lowest value. Regarding fruit total sugars content the application of olive pomace alone or combined with the minerals increased fruit total sugars content, as compared to mineral fertilization. Fruit tannins were significantly higher when palms were fertilized with olive pomace alone as compared to other treatments. Adding olive pomace combined with minerals (N, NP and NK) significantly increased yield / palm than that of the control. Fertilizing with 25 Kg olive pomace combined with NK significantly increased the average fruit and pulp weight, fruit length and diameter as compared with the control. No significant differences were found between different treatments in seed weight. According to the conditions of this experiment, it is recommended to fertilize Hayany date palm with 25 Kg olive pomace combined with NK which gave a reasonable yield with high fruit quality.