Early selection of elite clones of an ornamental bromeliad in vitro/ Selecao precoce in vitro de clones elite de uma bromelia ornamental

Orthophytum grossiorum is a typical bromeliad from Atlantic forestry threatened of extinction. The objectives of this research were to select O. grossiorum clones with ornamental values easy to propagate in vitro, and establish in vitro propagation protocols for these clones. The project was developed in three steps: germination and in vitro selection of seedlings responsive to BAP (6-benzylaminopurine), selection of clones with ornamental values, and establishment of protocol for in vitro propagation of the selected clones. In the first step only 18.33% of plantlets germinated in vitro were responsive to BAP. These plantlets were selected and replicated in vitro several times, each replicated plantlet constituting a clone. In the second step these clones were established ex vitro and surveyed for ornamental attributes. Five out of 11 clones were selected in this step. These clones presented distinct phenotypic traits and were considered of high ornamental quality. In the third step a protocol for in vitro propagation was developed for each selected clone. Key words: micro-propagation, tissue culture, breeding. Orthophytum grossiorum e uma bromelia ameacada de extincao tipica de Mata Atlantica. Os objetivos deste trabalho foram selecionar clones de O. grossiorum com potencial ornamental e de facil propagacao in vitro e estabelecer protocolo de propagacao in vitro para esses clones. O trabalho foi desenvolvido em tres etapas: germinacao e em selecao in vitro de plantulas responsivas a BAP (6 benzylaminopurine), selecao de clones com valores ornamentais e estabelecimento de protocolo para propagacao in vitro dos clones selecionados. Na primeira etapa, foi observado que apenas 18.33% das plantulas germinadas in vitro eram responsivas a BAP. Essas plantulas foram selecionadas e reproduzidas em in vitro, e cada plantula selecionada e reproduzida constituiu um clone. Na segunda etapa, esses clones foram estabelecidos ex vitro e selecionados em relacao aos atributos ornamentais. Nessa etapa, foram selecionados cinco entre 11 clones. Esses apresentaram caracteristicas fenotipicas distintas, sendo considerados de alta qualidade ornamental. Na terceira etapa, o protocolo para em propagacao in vitro foi desenvolvido para cada clone selecionado. Palavras-chave: micropropragacao, cultura de tecido, melhoramento.