Optimization of in vitro regeneration in Hibiscus subdariffa L. – An important medicinal plant

In vitro propagation methods using nodal segments of young tissues of Hibiscus subdariffa plant have been established. The nodal shoot segments responded better than apical shoot tip explants. Murashige and Skoog (MS) semi-solid medium supplemented with 1.0 mg/L 6-benzylaminopurine (BAP) induced 4.2 ±0.24 shoots per node with 2.40 ±0.18 cm in length after four weeks of inoculation. About 92% explants responded on this medium combination. The shoots were further multiplied (8.2 ±1.37 shoots with 5.9 ±1.05 cm length) by repeated subculture of mother explants and freshly induced shoot clumps on MS medium with the reduced concentrations of BAP and Kinetin (0.5 mg/L each) with additives within 4 weeks. Half strength MS medium augmented with 2.0 mg/L indole-3 butyric acid (IBA) was found most favorable for root induction with 98% response. On this medium 7.5 ±0.61 roots with 4.8 ±0.23 cm length of roots were recorded. The regenerated plantlets were successfully hardened and field transferred.