Micropropagation and Conservation of the Wild Medicinal Orchid, Coelogyne cristata

Micropropagation of the wild medicinal orchid, Coelogyne cristata, was conducted through culture of shoot axis, intact seedlings and pseudobulb segments. The shoot axis cultured on half strength Murashige and Skoog (1/2 MS) medium with 0.44 mg.L-1 thidiazuron (TDZ) gave the optimum shoot response and fresh weight. Higher concentrations of TDZ above the optimum level seemed to gradually increase inhibitory effects on shoot regeneration and plant growth. Intact seedlings showed maximum number of shoots on Murashige and Skoog (MS) medium with 1.0 mg.L-1 naphthalene acetic acid (NAA) and 1.0 mg.L-1 6-benzylaminopurine (BA) combination, without activated charcoal (AC). In two types of pseudobulb segment (basal and terminal segments) culture, basal segments produced better shoot response in all treatments than that of terminal segments. Of different inoculum types, medium and growth regulators used in the present study, the culture of seedlings on MS media with 1.0 mg.L-1 NAA and 1.0 mg.L-1 BA combination without AC appears to have great potential for in vitro propagation of this extremely wild orchid. The obtained plantlets showed no genetic variation.