The effect of foliar spray of nitrogen, boron and zinc on the growth indicators and the content of the leaves of elements of two olive cultivars (Nebaly mohasan and Dan)

This experiment was carried out during 2009 and 2010 seasons in fields cultivated with 10 years of Dan and Nebaly cultivars of olive trees in province of Damascus to study the effect of foliar spray of to one of nitrogen (N), boron (B) and zinc (Z) on the leaf area, shoot length, number of flowers, leaves content of mineral elements, fertilization. These elements were sprayed individually or combined together four times during the growing season as follows: nitrogen (5 g/l), boric acid (2g /l), zinc sulfate (2g/ l), nitrogen + boric acid, nitrogen + zinc sulfate, Boric acid + Zinc sulfate, and nitrogen + boric acid + zinc sulphate) at the same rates in single spray.