EFFECT OF DIFFERENT ORGANIC FERTILIZER SOURCES ON IMPROVING FRUIT NUTRITIONAL VALUE AND YIELD OF 'ZAGHLOUL' DATES

A field study was carried out during the 2007 and 2008 seasons on ‘Zaghloul’ cultivar growing in clay soil. One level of N alone or plus PK from mineral (ammonium nitrate alone or plus calcium superphosphate + potassium sulphate, NPK) and organic sources (chicken manure, cow dung and town refuse compost) were applied either alone or in combinations in order to study their influence on yield and fruit physical and chemical quality. The results revealed that organic manure either alone or combined with mineral fertilizers increased palm yield and enhanced fruit color as compared with mineral fertilization alone. Chicken manure and cow dung resulted in the best fruit weight and fruit length. Fruit TSS, anthocyanin and sugars increased and tannins content was decreased by chicken manure and cow dung as compared with combining organic manure with NPK or mineral alone. In general, micronutrients contents were significantly higher in fruits by applying organic manure alone than organic manure combined with NPK or mineral fertilization alone. Organic manure fertilization alone (especially CM and CD) resulted in decreasing fruit Pb and Cd contents compared to mineral fertilization.