IMPROVING MICROPROPAGATION PROTOCOL FOR CAROB (Ceratonia siliqua)

Carob (Ceratonia siliqua, Fabaceae) is a Mediterranean tree with socio-economic and ecological interests. The conventional propagation of carob is difficult, therefore, micropropagation offers an efficient alternative to respond to the increasing demand for this valuable plant. In vitro culture establishment of explants from an adult tree was successfully performed on Murashige and Skoog (MS) medium supplemented with 4.4 μM 6-benzylaminopurine (BAP) and 2.46 μM 2-isopentenyladenine (2iP) for stem node segments, while direct organogenesis from leaf segments was optimum on MS medium supplemented with 4.54 μM 1-phenyl-3-(1,2,3-thiadiazol-5-yl) urea (TDZ). Leaf segments produced twice the number of shoots (10.67 shoots/explant), compared to the stem node segments. The highest proliferation of shoots was observed on MS medium supplemented with 8.9 μM BAP and 2.46 μM 2iP. Root induction was observed on the shoots cultured on MS medium supplemented with 9.8 μM indole-3-butyric acid (IBA) and 1.9586 μM tryptophan (Trp) on 86.67% of shoots. Well rooted plantlets were successfully acclimatized to the greenhouse. This report describes an improving protocol for the micropropagation of carob to respond to the needed efforts to cultivate carob in Egypt.