In vitro nodal segment cultivation of wild accessions of pineapple

The use of nodal segments from in vitro etiolated plants is an alternative for micropropagation of pineapple plants. The aim of this work was to evaluate the micropropagation of ten accessions (BGA-025, BGA-203, BGA-205, BGA-206, BGA-207, BGA-232, BGA-233, BGA-465, BGA-472 and BGA-772) from wild varieties of Ananas comosus var. microstachys using nodal segments from in vitro etiolated plants. Fourteen plants of each accession were introduced in MS medium, supplemented with 3% of sucrose, 0.54 μM NAA and 0.89 μM BA, solidified with 7 g L(‑1) of agar and pH adjusted to 5.8 in the etiolation stage under dark condition at 27±1°C. The nodal segments obtained were used for multiplication and were inoculated on MS medium with 30 g L(‑1) sucrose, 0.54 μM NAA and 0.89 μM BA, solidified with 7 g L(‑1) agar and pH adjusted to 5.8, under 16-h photoperiod and light intensity of 22 µmol m‑2 s(‑1) and 27±1°C. To evaluate plant etiolation, the following traits were measured after 60 and 90 days of incubation: length of the principal stem (cm); number of stems; number of nodal segments stem(‑1) and formation of aggregates (clusters). The multiplication rates were evaluated in five subcultures at intervals of 45 days, considering the number of buds plant‑1. The response of accessions to etiolation was variable and the best multiplication rates were obtained with accession BGA-203. The use of nodal segments from in vitro etiolated plants was effective for most accessions evaluated.