INFLUENCE OF CHEMICAL FERTILIZER, EM BIOSTIMULANT AND THEIR COMBINATIONS ON GROWTH AND QUALITY OF PHOENIX DACTYLIFERA L. CV. SIWI OFFSHOOTS

A trial was carried out at the Experimental Farm of Hort. Res. Inst., ARC, Giza, Egypt during 2013 and 2014 seasons to study the effect of individual application of EM biostimulant solution at 25 ml/l, NPK complete chemical fertilizer (20:20:20 + microelements) at the rates of 0, 2.5, 5.0, 7.5 and 10.0 g/bag and their combinations on growth and chemical composition of 2-years – old offshoots of date palm (Phoenix dactylifera L.) cv. Siwi planted in 50- cm-diameter plastic bags filled with about 35 kg of a mixture of sand and clay (2 : 1, v/v) under the full sun. The results showed that all fertilization treatments used in this study markedly improved all vegetative growth characters with various significant levels when compared to control in both seasons. The results indicated also that EM solution alone gave means closely near to those gained by NPK complete fertilizer at 5 g/bag with few exceptions in the two seasons. Moreover, increasing application rate of NPK fertilizer to 7.5 g/bag or more did not cause a pronounced increment in growth, but combining between EM treatment and NPK fertilizer at any rate did so, with the superiority of combining between 25 ml/l EM and 5 g NPK/bag, as this combination gave the highest means over all sole and other combined treatments in both seasons. Similar observations were also attained concerning the leaf let content of N, P, K, total indoles, chlorophylls a and b and carotenoids. Hence, it can be recommended to treat the 2-years-old offshoots of date palm cv. Siwi cultivated in 50-cm-diameter plastic bags with EM solution at 25 ml/l and NPK complete fertilizer at 5 g/bag to improve growth and quality of such offshoots before transferring to the permanent field.