Influência do meio de cultura, tipo e concentração de citocinina na multiplicação in vitro de Brassavola tuberculata Hook

Abstract

Brassavola tuberculata Hook., better known popularly as "chive" because of its cylindrical or slightly tapered leaf, is a native and epiphytic orchid, which has inflorescences with large numbers of flowers, pleasant scent, long flowering period and flower durability, characterizing High ornamental potential. Another important characteristic of the species is the possibility of crossing with other genera and obtaining new hybrids. Considering the importance of the species, the development of efficient in vitro propagation protocols is necessary to guarantee the production of seedlings, either for commercial purposes or for conservation purposes. Thus, the objective of this study was to evaluate the in vitro multiplication capacity of B. tuberculata using three - leafed nodal explants from microplants previously germinated in vitro. In order to reach the proposed objective, the culture in WPM medium supplemented with different types of cytokinins with 5.0 mg L-1 (BAP, 2iP and Zea), with and without the presence of activated charcoal in the concentration of 1.0 g L -1 , as well as the performance of B. tuberculata cultured in MS and WPM culture media supplemented with different concentrations of BAP (0, 2.5 and 5.0 mg L-1 ). After 60 days of cultivation, it was concluded that for the in vitro multiplication of Brassavola tuberculata, the use of BAP associated with 1 g L-1 of activated carbon is recommended for obtaining a greater number of leaves and lengthening of shoots. Regarding the tested concentrations of BAP and culture medium, the results indicate that, in the tested concentrations, the use of 2.5 mg L-1 of BAP in MS medium favors the development of shoots and leaves. The cultivation in WPM medium favors the rooting, damaging the development of the aerial part.