IN VITRO CULTURE ESTABLISHMENT OF CERATONIA SILIQUA (L.) MATURE TREES FROM CULTIVARS OF DIFFERENT MEDITERRANEAN COUNTRIES

In this study, juvenile and 1 year-old apical and axillary buds collected from selected mature trees of cultivars from Italy, Portugal, Spain and Morocco, were used for in vitro initiation. Several methods of superficial disinfection were tested. Two media were used: MS (Murashige and Skoog, 1962) and ½MS (half-strength macronutrients MS) supplemented with 0.5 mg/L BA (6-benzyladenina). The lower rate of contaminations, associated with the best morphogenetic response of the buds, were obtained with explants from juvenile shoots collected between April and October treated with HgCl2 at low concentrations (0.1, 0.2%) for 5 min. Commercial bleach and ethanol were not efficient to get an effective response. Half-strength MS medium supplemented with 0.5 mg/L BA, was the best medium for the establishment of cultures since it did not cause hyperhydricity symptoms. On the whole the results show that the in vitro establishment of several carob tree cultivars is possible but adjustments are needed depending on the variety, explant type and season