ESTABLISHMENT AND OPTIMIZATION OF AN EFFICIENT IN VITRO REGENERATION SYSTEM OF ONCIDIUM, WILSONARA, ODONTOCIDIUM AND VUYLSTEKEARA

Hybrids of Oncidium and Odontoglossum are orchids with a wide spectrum of flower colors and patterns and also with increasing economic importance. The objective of this study was to develop an efficient protocol for in vitro regeneration via somatic embryogenesis. Starting from in vitro shoot cultures of the cultivars Oncidium Sweet Sugar 'SP 12' and Sharry Baby var. aureum 'OK', as well as the hybrids Wilsonara Stirling Tiger, Odontocidium Hansueli Isler and Vuylstekeara Cambria 'Plush', we established a reliable protocol for regeneration of somatic embryos. The most suitable type of explants were leaf tips, on which the formation of protocorm-like bodies was observed in frequencies of 60% after 12 weeks. The most efficient regeneration was obtained on medium containing 1 mg/L thidiazuron and cultured in complete darkness.