In vitro propagation of Ananas comosus var. ananassoides (Baker) Coppens & F. Leal (Bromeliaceae)

Resumo

Ananas comosus var. ananassoides (Baker) Coppens & F. Leal is a terricole ornamental bromeliad native of the Cerrado. Since this biome is threatened of extinction, studies about the cultivation of seedlings of this species are important and the in vitro culture can be a useful tool for its propagation. This work aimed to multiply A. comosus var. ananassoides in vitro, by means of nodal segments, and with the culture medium containing different nitrogen (N) concentrations. In obtaining the nodal segments, the plants remained in vitro in the dark for three months. In the other experiment, the seedlings were cultured in vitro in MS medium containing different N concentrations for six months. The results showed that 92% of the plants presented stem etiolation in the dark, each plant generat­ing three to four nodes, and these nodes gave rise to healthy plants. Moreover, in vitro multiplication with 15 mM and 30 mM N was found to be possible, yielding 1.5% and 3% multiplication, respectively, with each plant gene­rating one or two buds. It is concluded that the production of plants by nodal segments is indicated for the in vitro multiplication of this species and it is suggested to culture it in 15 mM N.