Eurycoma longifolia is a potent remedy that has been traditionally used for male libido, sexual prowess and fertility improvement in South-East Asia. Conventional propagation via seed germination is the most common method of E. longifolia propagation and like other woody plants it is usually unsatisfactory because of low rate of seed germination. Therefore establishment of a tissue culture technique for rapid and effective propagation protocol is an urgent need. In this study, an efficient method was achieved for multiple shoot regeneration using cotyledonary node as an explant of E. longifolia. MS medium supplemented with different concentrations of cytokinins such as benzyl amino purine (BAP), Kinetin (KIN) and Thidiazuron (TDZ) were evaluated for shoot induction. Various concentrations of indole-3-butyric acid (IBA) were also used for root induction. The results showed that the highest frequency(76.7%) of multiple shoots induction was observed at 1.0 mg/l of BAP and the maximum shoot number per explant( 3.53 shoots) was obtained within three weeks from a single cotyledonary node at 1.0 mg/l of BAP. Shoots were established by subculturing the cotyledonary nodes on fresh medium with same concentration after each harvest of the new shoots. For root induction, individual shoot (2.5 – 4.5 cm) in height was aseptically excised from cotyledonary nodes and transferred to rooting media. The highest rooting frequency (80%) and the maximum number of roots (3.20 roots) were recorded in half-strength MS salts supplemented with 0.5mg/l of indole-3-butyric acid (IBA). Regenerated plantlets were successfully acclimatized to ex vitro conditions. Overall, in vitro regeneration system provides improved technology that can help to propagate this medicinal plant.

Keywords: Multiple shoots, Cytokinins, Eurycoma longifolia, Cotyledonary nodes, in vitro shoot proliferation.