Cyrtopodium paludicolum is a terrestrial orchid species, native to Brazil, whose natural propagation is jeopardized by the intensive collection from the wild and is threatened by agricultural expansion in Cerrado areas. In light of that, this investigation aimed at studying the in vitro germination and early development of C. paludicolum as influenced by culture medium, sucrose and growth regulators as well as its micropropagation by using dark-grown stem segments. A protocol for its acclimatization is also detailed. The effects of Murashige & Skoog (MS), Knudson C (KC) and Vacin & Went (VW) media on the in vitro germination and initial development were tested. The influence of different concentrations of BA, NAA, and of sucrose on plant multiplication and growth were evaluated. The possibility of using etiolated stem segments for micropropagation was also assessed. Acclimatization was accomplished in two phases by using three different substrates. The results showed that VW was the best medium for germination whereas for seedling formation KC was the most advantageous since they were healthy and vigorous. Sucrose at 2% favored the greatest seedling growth and development. Shoot and root proliferation and development were best promoted in the presence of 2.28/2.28 and 0.57/0.57 µM BA/NAA, respectively. The use of etiolated stem segments for micropropagation was effective. Successful acclimatization was accomplished by initially growing plants in community pots containing a 3:1 (v/v) mix of Bioplant and dried Sphagnum moss followed by their transfer to individual pots containing a 2:1 (v/v) mix of Bioplant and Ouro Negro substrates.

Oeceoclades maculata is a terrestrial orchid species that has potential for commercial purposes. Taking that into consideration, the present investigation aimed at studying its germination and initial development in vitro as well as its acclimatization. The influence of Murashige and Skoog (MS), Knudson C (KC), and Vacin and Went (VW) media in the presence and absence of 0.3% activated charcoal on in vitro germination and protocorm development were investigated. The effects of different concentrations of BA in combination with 0.5 mg L-1 NAA on seedling multiplication and growth were evaluated. The possibility of using dark-grown stem segments for micropropagation and acclimatization under laboratory and field conditions was also assessed. The results indicated that the most adequate media for germination were full-strength MS enriched with activated charcoal or KC supplemented with 1.5 mg L-1 BA in combination with 0.5 mg L-1 NAA. In terms of protocorm development, KC supplemented with 1.5 mg L-1 BA alone or in combination with 0.5 mg L-1 NAA provided the best results. The addition of 1.5 mg L-1 BA in combination with 0.5 mg L-1 NAA to KC medium favored the best results for seedling multiplication and development. The use of dark-grown stem segments is a viable alternative for the micropropagation of O. maculata. Regarding acclimatization, 100% survival of plants was observed during the initial phases and under field conditions average survival was 53.33%.