In vitro propagation of orchid-Dendrobium ‘Sonia’

Effect of different nutrient media and growth regulators on in vitro establishment and differentiation of meristem and subsequent growth and development of mericlones was studied in Dendrobium ‘Sonia’. Establishment and differentiation of meristem, subsequent growth and development of mericlones was high in Murashige and Skoog medium and it was very poor in Knudson C and Morel media. Differentiation of meristem was early with BAP 0.1 mg l⁻¹ + NAA 1.0 mg l⁻¹. Maximum number of multiple shoots was observed in BAP 1.0 mg l⁻¹ + NAA 1.0 mg l⁻¹. Protocorm like bodies (Plb's) were produced at lower concentration of NAA, while higher concentration produced succulent, dark green leaves with rosette appearance. Early leaf initiation with better organogenesis i.e. maximum shoot and root length, more number of leaves, maximum leaf area, increase in fresh and dry weight was observed in MS medium supplemented with BAP 0.1 mg l⁻¹ + NAA 0.1 mg l⁻¹. Root formation was better in NAA 1.0 mg l⁻¹. Hundred per cent survival and better growth of plantlets was observed in potting media having either wood charcoal pieces alone or crushed tree bark alone.