Micropropagation of Syngonanthus elegantulus Micropropaga o de Syngonanthus elegantulus

The species Syngonanthus elegantulus Ruhland is an important native plant used as cut flowers, but extractive exploration has caused the endangered status of this plant. Therefore, the objective of this study was to establish a protocol of the micropropagation of S. elegantulus. To this end, seed germination was tested in media containing different concentrations of WPM salts. For plantlet establishment, MS and WPM media were evaluated with 50 and 100% of the salt concentrations. Different the sucrose levels in the WPM medium were also evaluated. For multiplication, the plantlets were inoculated in WPM media with 0.0, 0.5, 1.0, 2.0 and 4.0 mg L-1 TDZ and 0.0, 0.5 and 1.0 mg L-1 NAA in all possible combinations. The pre-acclimatization effect was tested in the plantlets using the following substrates: sand, PlantmaxTM and vermiculite. The concentration of the medium did not influence the percentage of germination, but the germination speed index was inversely proportional to the nutrient addition to the culture medium. The best medium for plantlet establishment was WPM at the original salt concentration plus 17 g L-1 sucrose. The addition of 0.5 and 1.0 mg L-1 NAA is recommended for callus induction. The highest number of shoots was obtained in the presence of 1.0 mg L-1 TDZ or the combination of 1.0 mg L-1 TDZ with 0.5 mg L-1 NAA. S. elegantulus presented higher survival when acclimatized directly in sand. A espécie Syngonanthus elegantulus Ruhland é uma importante planta nativa usada como flor de corte, mas sua explora o extrativista tem causado risco de extin o. Assim, neste estudo, objetivou-se estabelecer um protocolo de micropropaga o de S. elegantulus. Para isso, a germina o das sementes foi testada em meio WPM, contendo diferentes concentra es de sais. Para o estabelecimento de plantulas, os meios MS e WPM foram avaliados com 50% e 100% de concentra o de sais. Diferentes níveis de sacarose em meio WPM também foram avaliados. Para a multiplica o de plantulas, foram inoculadas em meio WPM adicionado de 0,0, 0,5, 1,0, 2,0 e 4,0 mg L-1 de TDZ e 0,0, 0,5, 1,0 mg L-1 de NAA em todas as combina es possíveis. O efeito da pré-aclimatiza o de plantulas foi testado nos substratos areia, plantmaxTM e vermiculite. A concentra o do meio n o influenciou a porcentagem de germina o, mas o índice de velocidade de germina o foi inversamente proporcional à adi o de nutrientes. O melhor meio para o estabelecimento de plantulas foi o WPM, na concentra o de sais originais, adicionado a 17 g L-1 de sacarose. Para a indu o de calo, a adi o de 0,5 e 1,0 mg