Effect of cobalt nutrition on rosemary (rosmarinus officinals L.) B-endogenous hormons, chemical and nutritional contents

Two field experiments were conducted in Research and Production Station, National Research Centre, Nobaria Location, Beheara Governorate, Delta Egypt under drip irrigation system. Experiments were conducted to evaluate the effect of cobalt levels (0.0, 5.0, 7.5, 10.0, 12.5 and 15.0 ppm) on Rosemary endogenous hormons, chemical constituents and nutritional status during 2012 and 2013 seasons. The obtained results are summarized in the following: Cobalt significantly increase Rosemary herb endogenous hormons such as Auxins, Gibberllins, Cytokinens and Abscisic acid as well as chemical and nutritional contents compared with control. Cobalt at 10 ppm gave the greatest figures. Increasing cobalt levels more than 10 ppm reduces the positive effect. Finally, Cobalt enhancement Rosemary – oil- quality.