Callus induction and indirect regeneration of Thunbergia coccinea Wall

In vitro regeneration of Thunbergia coccinea Wall. ex D. Don via organogenesis was obtained from leaf callus tissue of T. coccinea, a perennial climbing medicinal vine plant with attractive red scarlet blooming in particular season. Highest weighted callus was obtained from leaves of T. coccinea on Murashige and Skoog basal medium supplemented with 5.0 mg/L NAA. Embryogenic callus were observed on MS basal media containing NAA rather than 2,4-D. Somatic embryogenesis was demonstrated by field emission scanning electron microscopic studies of some embryogenic callus. Highest frequency of somatic embryos was obtained in 3.0 mg/L NAA. Indirect shoot bud organogenesis and rhizogenesis were also observed on some embryogenic callus. Plantlets were regenerated from both somatic embryos and shoot buds. Highest number of shoots was noted in 0.1 mg/L NAA and 2.0 mg/L BAP combination while transferring in regeneration media. Regenerated plantlets were hardened successfully on pot. The survival rate of regenerated plants after hardening was 50%.