In vitro propagation of Eremostachys superba Royle ex Benth.-an endangered, medicinal and ornamental herb of North-West Himalaya

Eremostachys superba is one of the most threatened species of the North-West sub-Himalaya with potential medicinal and ornamental values. Efficient in vitro protocol has been developed for the propagation of E. superba from shoot tip explants of seedlings raised in vitro from seeds. Shoot organogenesis in shoot tip explants was promoted by inoculating these explants on Murashige and Skoog (MS) medium fortified with cytokinins (BAP, TDZ & Kinetin) and auxin (NAA). The best morphogenetic response (number of shoots per explant, shoot length and frequency of shoot regeneration) was observed when explants were incubated on half-strength MS medium containing BAP (6.6 μM) and NAA (0.53 μM). Multiple shoots were also observed in the full strength MS medium fortified with BAP (6.6 μM) and NAA (0.53 μM), but callusing was also reported in addition to multiple shoots. Well developed in vitro raised shoots were shifted to rooting mediums fortified with different concentration of auxins (IAA, IBA & NAA). Best morphogenetic response (100%) was observed in quarter strength MS medium containing IBA (7.36 μM) and 16.4 roots per shoots was reported. In addition to rooting, callusing was also reported at cut ends of shoots in full and half-strength MS medium. Plantlets regenerated in vitro were acclimatized in the green house under shade net and were successfully transferred to the open environment.