Marwen Mechergui, LRME, Faculty of Sciences of Tunis FST, University of Tunis El Manar, Tunisia., Tunisia; Nouha Mezned, Faculty of Sciences of Bizerte FSB, University of Carthage, Tunisia & LRME, Faculty of Sciences of Tunis, University of Tunis El Manar, Tunisia., Tunisia; Larbi Ajmi, Laboratory of Integrated Olive Production, Olive Tree Institute, Tunis, Tunisia., Tunisia; Sâadi Abdeljaouad, LRME, Faculty of Sciences of Tunis FST, University of Tunis El Manar, Tunisia., Tunisia