Propagation of Ornamental Plants
5(3): 129-136, 2005
ESTABLISHMENT OF OPTIMUM NUTRIENT MEDIA FOR IN VITRO PROPAGATION OF CYMBIDIUM SW. (ORCHIDACEAE) USING PROTOCORM-LIKE BODY SEGMENTS
Jaime A. Teixeira da Silva¹*, Tim Wing Yam², Seiichi Fukai¹, Nihar Ranjan Nayak³ and Michio Tanaka¹
¹Department of Horticultural Science, Faculty of Agriculture, Kagawa University, Miki cho, Kagawa 761-0795, Japan, *Fax: +81 (0)87 898 8909, *e-mail: firstname.lastname@example.org
² Singapore Botanic Gardens, 1 Cluny Road, 259569, Singapore
³ Plant Sciences Department, University of Kentucky, Lexington, KY 40546-0312, USA
A total of 14 basal media were tested for their ability to promote organogenesis from the protocorm-like body (PLB) of Cymbidium. Media tested included 3 controls and 11 media containing various plant growth regulators (PGRs). Media containing NAA and kinetin at 0.1 mg l-1 were used to induce PLB formation. Media containing 0.1 mg l-1 TDZ (thidiazoron) and NAA were used for callus induction. Experiments were carried out to test the suitability of various media to induce organogenesis such as PLB formation, callus proliferation, or shoot and root development. Cluster analysis revealed three groups of media: the first group of media has the tendency to enhance callus and PLB formation (Vacin and Went, Phytamax, Knudson C); the second group promotes PLB formation with very little callus (White, Hoagland's № 2); the third group promotes good callus formation but very little PLB (Murashige and Skoog with or without Gamborg's micronutrients, Gamborg's B-5); the last group produces a small amount of both callus and PLB (Chu (N6), Schenk and Hildebrand, WPM, Quoirin and Lepoivre). In a separate study, the effect of sulphate source on PLB formation was investigated. Magnesium sulphate was shown to be a better source of sulphate than potassium sulphate. After the shoots were derived from PLB, they were subcultured on the same basal media to find out if the media are suitable for promoting shoot or root growth. Plants developed from PLB-derived shoots were cytologically similar. They were also found to have similar photosynthetic capacities (SPAD values). Plants could be 100% acclimatized, with a resulting survival rate of 100%.
Key words: callus, flow cytometry, macronutrients, micronutrients, orchid, PLB, SEM.