The Millenary History of the Fig Tree (Ficus carica L.)

Ficus carica L. is a classical fruit tree of antiquity, it goes back to the beginning of horticulture in the Mediterranean basin. Domestication produced substantial modifications on the primitive characteristics of the plant, for example by increasing the sugar content and the size of the fruit and determining a gradual shift toward vegetative propagation. However in the wild the spreading of the species is entirely dependent on seed. A very particular feature of this species is the reproductive biology which is regulated by a mechanism of extraordinary complexity based on the mutual symbiosis between the plant and its pollinator wasp Blastophaga psenes. This review provides the description of the intertwined life cycle plant-insect, of the floral biology and of the genetic control determining the different floral forms and the two sexual forms of tree. A part of this review is dedicated to the cytogenetic background of F. carica emphasizing the importance of recent investigations revealing the presence of polyploid cytotypes within wild and cultivated Italian populations. Considerations on the sexual reproduction and the genetic constitution of the fig cultivars are also reported.