Olive, Olea europaea L., is one of the oldest agriculturaltree crops. The genus Olea consists of more than 30 different species, with only Olea europaea L. being cultivated. The olive tree is a perennial evergreen and its flowers show varying levels of self-incompatibility. It is a widely planted in regions with Mediterranean climate and is economically important both for oil and table use. Moreover, olive is one of the oldest and most important crops found in the Mediterranean area and its cultivation is presently expanding into areas of South America, Australia and South Africa. Moreover,...