Micropropagation of Vanda coerulea Griff ex Lindl.: A study of regeneration competence of roots in vitro

A rapid and efficient procedure is outlined for in vitro propagation of Vanda coerulea Griff. ex Lindl., an endangered epiphytic orchid. Root segments (0.5–1.0 cm long) from plants growing both in vivo and in vitro were cultured on MS (Murashige and Skoog, 1962) medium supplemented with auxins [Indole 3-acetic acid (IAA)], cytokinins [6-benzyl aminopurine (BAP), 6-furfuryl amino purine (KN)] and coconut water (CW). The root explants from in vivo sources failed to respond whereas those from in vitro grown plantlets regenerated protocorm-like bodies (PLBs). An optimum of 16.2 PLBs developed from root explants on medium supplemented with 30µM BAP and 15µM IAA. The resulting plantlets were successfully transferred to pots containing brick pieces, charcoal chunks and decaying litter (1∶1∶1) + a top layer of moss. Ninety-five percent of the plantlets survived in the glass house after two months of transplantation.