An efficient in vitro regeneration protocol for a natural dye yielding plant, Strobilanthes flaccidifolious Nees., from nodal explants.

Adventitious shoot buds formation from axillary buds of nodal segments of S. flaccidifolious was achieved on MS medium containing sucrose (3%, w/v), and α-naphthalene acetic acid (NAA; 3 µM) and benzyl adenine (3 µM) in combination. The nodal segments were primed on ‘Growtak Sieve’ for 48 h on MS medium containing sucrose (2%), polyvinyl pyrollidone (200 mgL-1) as antioxidant. About 80% of primed nodal segments responded positively and formed ~12 adventitious shoot buds per explants from explants collected during October-November months of every year. The shoot buds converted into plantlets on MS medium containing sucrose (3%) and kinetin (3 µM) where ~7 micro shoots developed per subculture after 8 weeks of culture. The regenerated micro shoots induced average 14 roots/ plant on medium containing NAA (3 µM). The regenerates were hardened for 6-7 weeks on medium with ½MS salt solution and sucrose (2%) under normal laboratory condition before transferring to potting mix. About 70% transplants survived after two months of transfer.