In Vitro Propagation of Mature Carob Trees (Ceratonia siliqua L.) from the Axillary Buds

摘要

The influence of tree age and the effect of growth regulators on the micropropagation of the carob (Ceratonia siliqua L.) from the axillary buds of mature trees have been described. Significant differences (P 0.005) in results are obtained in the stages of initiation, multiplication, and rooting according to their response to the various concentrations of different growth regulators examined, namely BA, IBA, AG_3. The use of 0.5 mg/l BA and 0.2 mg/l IBA was the most favorable for shoots neoformation. The leafy shoots are propagated in MS medium with BA at a concentration of 1.5 mg/l. The addition of gibberellic acid at 0.2 mg/l in the culture medium allows a good elongation and development of the shoots of the carob. The effect of the age of the plant material used has shown that explants taken from mature carob trees have a low capacity for bud sprouting and shoot proliferation compared to those taken from juvenile trees. Rooting has been successful when the plant material used is taken from young trees on an MS medium containing 2 mg/IBA, with an average number of 3 to 4, roots 1 to 2 cm long, then for the adult material, no rooting was observed. Based on these tests, it appears that micropropagation of the carob from the axillary buds is feasible, but additional work must be done to root this recalcitrant material.