In Vitro Propagation Using Transverse Thin Cell Layer Culture and Homogeneity Assessment in Ceropegia bulbosa Roxb.

Ceropegia bulbosa is an endangered medicinal plant used traditionally in the treatment of various diseases. Our aim is to develop a rapid and a competent procedure for direct and indirect organogenesis from transverse thin cell layer (tTCL) explants of C. bulbosa. Optimum response to direct adventitious shoot bud induction from tTCLs was observed on medium augmented with 8.8 µM 6-benzyladenine (BA) producing 15.6 ± 0.31 shoots per responsive explant. Best callusing response (95 %) was observed with tTCL explants in medium containing 4.5 µM 2,4-dichlorophenoxyacetic acid and 2.2 µM BA. High frequency shoot regeneration (75 %) was observed from tTCL derived calli. Medium containing 8.8 µM BA and 0.27 µM α-naphthalene acetic acid produced 22.2 ± 0.64 shoots with shoots acquiring an average length of 4.6 ± 0.12 cm. In vitro rooting was recorded on ½ strength Murashige and Skoog medium, producing 10.9 ± 0.23 roots with a length of 4.24 ± 0.16 cm. Plants were successfully transferred to the field with a survival rate of 89 %. The clonal nature of the regenerants was assessed using Inter-simple sequence repeat markers.