Establishment of an efficient protocol for micropropagation of stem explants of <i>Tylophora indica</i>, an important medicinal plant

Abstract

An efficient reproducible protocol has been developed for in vitro propagation of endangered medicinal plant (Tylophora indica). The concentration of plant growth regulators and explant types exhibited discrete roles in the efficiency of plant regeneration. Stem explants cultured on 8.8 μM 6- benzylaminopurine (BAP) resulted in formation of nodular meristemoids, which developed into green leafy shoots 6 to 8 weeks after culturing on the same medium. 29.4 μM α-naphthalene acetic acid (NAA) and 4.65 μM kinetin (Kn) induced green solid callus within 7 to 8 days of culturing. Callus thus formed, revealed the presence of cells of variable shapes and sizes together with xylogenesis. Calli when subcultured on MS medium supplemented with 8.8 μM BAP developed adventitious shoots, however, initially, few shoots were formed but the number increased further on subsequent subculturing. Microshoots thus formed, were cultured on indole 3-butyric acid (IBA) and half strength basal MS media for induction of roots. Regenerated plantlets with healthy shoots and roots were acclimatized in moist cotton followed by their hardening in soil : vermicompost potting mixture with 90% survival rate.

Key words: Tylophora indica, organogenesis, 6-benzylaminopurine, α-naphthalene acetic acid, indole 3- butyric acid.