Effect of indole-3-butyric acid (IBA) on in vitro root induction in dendrobium orchid (Dendrobium sabin H.)
Root induction pre-developed in vitro plantlets of orchid was carried out using indole-3-butyric acid (IBA) (0, 0.5, 1.0, 1.5, 2.0, 2.5 and 3 mM) on basal Murashige and Skoog (MS) medium. Among the concentrations of IBA, the number of roots per plantlet with 1 mM IBA was found to be the highest (2.25 roots per plantlet) followed by 2.0 mM IBA (1.61 roots per plantlet) after 40 days of culture. Significantly high root length (0.96 cm) was found on MS medium supplemented with 1 mM IBA followed by 1.5 mM IBA (0.63 cm). For root initiation, the least amount of time (11.0 days) was required by 1 mM IBA followed by 0.5 mM and 1.5 mM. This study conclude that IBA treatments at lower concentration proved to be effective in root formation of orchid.
Key words: Orchid, IBA concentration, in vitro propagation, root induction.