1. Biochemistry Department; Faculty of Agriculture; Zagazig University; Zagazig 44519 Egypt
2. Institut de l'Olivier; BP 14, 4061 Sousse Ibn-khaldoun, Tunisia
3. Everglades Research & Education Center; University of Florida-IFAS; 3200 East Palm Beach Road Belle Glade FL 33430 USA
4. Plant Physiology; University of Bayreuth; Bayreuth D-95440 Germany