An-Najah Staff

In Jordan, 3 experiments were conducted to study the effects of time of collection and indolebutyric acid (IBA) concentration on the rooting of terminal and basal stem cuttings of carob (Ceratonia siliqua). The collection dates were Feb., May and Oct. ; IBA was used at 0, 2000, 4000, 6000 and 8000 ppm. The cuttings were rooted in perlite under intermittent mist in a glasshouse with controlled temperature and humidity. Responses were evaluated on the basis of rooting percentage, root number and root length. Carob cuttings taken during Oct. did not root, nor did roots form without the use of IBA. Terminal cuttings gave better rooting than basal cuttings. The highest rooting percentage (55%) was obtained using terminal cuttings collected during Feb. and treated with 8000 ppm IBA; however, this percentage was not significantly different from the May collection date or other IBA concentrations. The interaction between cutting type and IBA concentration in cuttings collected during May was significant for the average number of roots, and the terminal cuttings treated with 8000 ppm IBA produced the highest value (16.63). From authors' summary. KEYWORDS: TROPAG | Ceratonia siliqua | trees | Ceratonia siliqua | cuttings | rooting | vegetative propagation | multipurpose trees | Jordan.