<i>In vitro</i> propagation of <i>Hoya wightii</i> ssp. <i>palniensis</i> K.T. Mathew, a highly vulnerable and endemic species of Western Ghats of Tamil Nadu, India

Abstract

In vitro propagation of Hoya wightii ssp. palniensis (Asclepiadaceae), a highly vulnerable and endemic plant species of Western Ghats, Tamil Nadu, India was carried out. Shoot tip explants were cultured on MS medium fortified with cytokinins (KN, BA, 2-iP and TDZ) in various concentrations and in combination with auxins (IBA, IAA and NAA). High frequency of shoot bud proliferation and multiplication was observed on KN (4.65 ìM) + IBA (1.47 ìM). Multiple shoot induction efficiency was increased on ascorbic acid (100 mg/l) supplemented medium along with KN (4.65 ìM) +IBA (1.47 ìM). Rhizogenesis was observed on MS medium supplemented with IBA (0.98 ìM), plantlets produced through micropropagation were hardened with the survival success of 56%. The efficient plantlet regeneration protocol developed would aid ex situ conservation of this vulnerable species.