Germplasm conservation of Oroxylum indicum Vent., an important medicinal plant, through an efficient micropropagation protocol using Gamborg's medium

The paper deals with rapid and efficient micropropagation protocol of Oroxylum indicum Vent., an important medicinal plant. Owing to very short viability period of its seeds as well as need for extra care in the first four years after conventional propagation, and excessive use by local people, its population in natural habitats has declined in the recent years. The in vitro culture of its nodal segments in Gamborg's B5 medium was performed for multiple shoot propagation and rooting in presence of various cytokinins and auxins. A maximum of ten shoots per explant was produced when 5.0 mg/l BA was supplemented in the medium, with maximum shoot length (3.74 cm) and leaf number (33.6) in presence of 0.3 mg/l KN and 5.0 mg/l BA, respectively after 60 days of culture. The maximum in vitro roots (5.2 per microshoot) was produced in half strength B5 medium supplemented with 0.5 mg/l NAA. The hardened and acclimatized plantlets were successfully transferred into potting mixture of soil, perlite and compost (1:1:1) with 70% survival rate.