Direct Somatic Embryogenesis of Curculigo orchioides Gaertn., an Endangered Medicinal Herb

In vitro multiplication of Curculigo orchioides was achieved by direct somatic embryogenesis in young leaf segments. Immature leaf segments of about 0.5 cm in length were cultured on MS medium supplemented with different concentrations of BAP (2-10 $\mu{M}$) or Kin (2-10 $\mu{M}$). Optimum response in terms of per cent cultures responding (89%) and the number of embryos per explant (16) were observed on MS medium supplemented with 8 $\mu$M BAP. The emergence of several somatic embryos on the adaxial side of the leaf segments was observed one month after the culture. Germinated somatic embryos were grown up to about 1.5 cm length before transferring to maturation medium. For maturation, the individual embryos were isolated and transferred to MS medium supplemented with BAP (5 $\mu{M}$) and NAA (0.5 $\mu{M}$). The plantlets emerged from the embryos were transferred to soil containing 1 peat: 1 sand with 90% success. The embryos were formed directly on the leaf segments without any callus phase. Direct regeneration of somatic embryos is important for the conservation of this endangered species, as rare somaclonal variants are likely to arise than from indirect regeneration.