THE EFFECT OF DIFFERENT THIDIAZURON AND INDOLE BUTYRIC ACID CONCENTRATIONS ON IN VITRO PROPAGATION OF 'GRAND NAIN' AND 'BASRAI' BANANA CULTIVARS

The aim of this study was to determine the optimum thidiazuron (TDZ) concentration for shoot multiplication and elongation for in vitro propagation of ‘Grand Nain’ (AAA) and ‘Basrai’ (AAA) banana cultivars. The effect of different concentrations of indole-3-butyric acid (IBA) (0, 1, 2.5, and 5 M) on rooting was also evaluated. Shoot tips were isolated from young suckers of ‘Grand Nain’ (AAA) and ‘Basrai’ (AAA) and transferred immediately to Murashige and Skoog (MS) medium with different concentrations of thidiazuron (0, 2.5, 5, 7.5, and 10 µM). The results showed that the shoot proliferation and rooting rate were both significantly affected by TDZ and IBA concentrations. Optimum multiplication of both cultivars was achieved on a MS medium with 2.5 µM TDZ (producing 4.35 to 4.61 shoots per explant). However, abnormal shoots were observed at concentrations >2.5 μM TDZ. IBA induced significantly better plantlet elongation and root production than MS medium alone when applied at the rooting stage. Supplementation of the 2.5 and 5 µM IBA improved root length and stem diameter.