An efficient in vitro regeneration and ex vitro rooting of Ceropegia bulbosa Roxb.—A threatened and pharmaceutical important plant of Indian Thar Desert

Ceropegia bulbosa Roxb. (family – Asclepiadaceae), a medicinally important plant, is classified as a ‘threatened plant’. An efficient protocol of shoot organogenesis and plant regeneration from seedling derived callus has been developed. Out of different explants i.e. epicotyl, hypocotyl, cotyledonary node and root, epicotyl was found to be the most suitable for establishment of cultures and further shoot regeneration. Callus was induced from epicotyl explants on MS medium containing 1.0 mg l−1 of 2,4-D. Proliferation of callus was observed on MS + 1.0 mg l−1 of 2,4-D and 0.5 mg l−1 of BAP. The shoot regeneration was achieved when proliferated callus was transferred to MS medium supplemented with BAP either alone or in combination with IAA or NAA. Maximum number (25.5) of shoots were regenerated on MS medium containing 1.0 mg l−1 BAP and 0.1 mg l−1 NAA. The shoots (100%) were rooted ex vitro when treated with IBA (100 mg l−1) for 3 min. Rooted plantlets were hardened successfully and transferred to the field. The described method can be successfully used for the large-scale multiplication and conservation of germplasm of this important and threatened plant.

► An efficient in vitro regeneration for Ceropegia bulbosa, a medicinally important and threatened plant, was developed.
► Epicotyl explants excised from 10 to 15 d old seedling was most suitable for shoot regeneration.
► Shoot regeneration from callus was influenced by interactive effects of plant growth regulators.
► Shoots were rooted ex vitro which makes it more economical in terms of labor cost and saving time.
► Ex vitro tuber formation was observed at the base of rooted shoot, the main source of alkaloid ‘cerpegin’.