Direct regeneration of plantlets from shoot tip explants of a vulnerable medicinal plant Celastrus paniculatus Willd.

Abstract: It is believed and essential that efforts should be made to develop protocols for vulnerable medicinal plants so as to develop new or more safe drugs. In this study, a rapid efficient plant propagation through direct shoot tip explant of Celastrus paniculatus Willd, a medicinal vulnerable plant (belonging to the family Celastraceae), was undertaken. Half strength Murashige and Skoog's (MS) medium supplemented with GA₃ showed maximum percentage (82.4 ± 0.50) embryo response through embryo rescue method. Shoot tip explants were transferred from cotyledonary node and inoculated to shoot induction medium supplemented with cytokinin (BAP, TDZ and Kin) and highest response (87 ± 0.70) with 3.8 shoot number was achieved in BAP 1.0 mg L^-1. Shoot multiplication was achieved with combination of BAP (1 mg L^-1) with meta - Topolin (1 mg L^-1) showed highest response (91.0±1.10) with 10.2 shoots within 10 days after inoculation. The in vitro regenerated shoots were transferred carefully to the half strength and full-strength MS medium supplemented with GA₃ (0.1 to 0.5 mg L^-1) for the elongation. The in vitro elongated shoots were treated with different auxins (IAA, IBA and NAA) individually for early rooting and treated shoots were transferred to the half strength MS medium. At the concentration IBA (0.3 mg L^-1), 91 % rooting was observed. The regenerated plantlets were acclimatized in pots containing sterilized soil and sand in 3:1 ratio and plantlets were then transferred to the field conditions. Ninty percent of the regenerants survived well. The result of the present study reveals the pioneer report on in vitro plant regeneration of C. paniculatus Willd. by using shoot tip explants.