<i>In vitro</i> propagation of orchid (<i>Dendrobium nobile</i>) var. Emma white

Abstract

Axillary buds of orchid Dendrobium nobile var. Emma white were proliferated by using phytotechnology medium (O753) supplemented with 0.5, 1.0, 1.5, 2.0, 2.5 and 3.0 mgl^-1 of benzylaminopurine (BAP) and kinetin (Kin) as well as coconut water (CW) at the rate of 50, 100, 150, 200, 250 and 300 ml. Maximum number of shoots (4.33), as well as fresh and dry weights (752.5 and 52.99 mg) were obtained at 2 mgl^-1 BAP, while 1.5 mgl^-1 of Kin exhibited the highest shoot length (4.18 cm). Higher concentrations of BAP, Kin (3.0 mgl^-1) and CW (300 ml) resulted in yellowing, necrotic shoots and poor growth. Root induction was carried out by using two auxins namely indolbutyric acid (IBA) and naphthalene acetic acid (NAA) at different concentrations (0.5, 1, 1.5, 2.0, 2.5 and 3.0 mgl^-1) on the modified MS medium. IBA at a level of 2 mgl^-1 increased the rooting percentage (97.5%) number of roots (4.70) and root length (3.47 cm) more efficiently than NAA. Higher concentrations of IBA and NAA (3.0 mg l^-1) showed poor results of rooting.

Key words: Orchids, in vitro propagation, coconut water, Dendrobium nobile.