Surface sterilization and micropropagation of Ludisia discolor

The jewel orchid Ludisia discolor, found in many parts of Asia, is valued due to its appearance and medicinal benefits. Existing surface sterilization protocols were found to be not successful in initiating in vitro cultures of L. discolor in this study. Hence, a surface sterilization protocol, incorporating the use of 0.4% (w/v) mercury chloride, was developed to address this issue. This method yielded the lowest contamination (7.7%) and best growth at 22.5%. Nodal segments of L. discolor produced the best growth when placed in half-strength semi-solid MS medium with 0.2% (w/v) activated charcoal, 8% (w/v) Mas banana cultivar homogenate, 3% (w/v) sucrose, 3.5 g L-1 Gelrite, 1.0 mg L-1 1-naphthaleneacetic acid, and 0.1 mg L-1 thidiazuron, a confirmation of the protocol promoted by Shiau et al. (2005). All in vitro cultures of L. discolor were successfully acclimatised under low light conditions using coconut coir, coconut husk and peat moss.