Initial in vitro plant establishment of seeds and nodal segments from bromeliad Acanthostachys strobilacea (Schult. & Schult.f.) Klotzsch differs in respiratory rates and shoot formation

Estabelecimento in vitro inicial de plantas de sementes e segmentos nodais da bromélia Acanthostachys strobilacea (Schult. & Schult.f.

ABSTRACT

We aimed to investigate the morphological and respiratory differences during in vitro shoot formation from seeds and nodal segments (NS) of Acanthostachys strobilacea (Schult. & Schult.f.) Klotzsch, due to differences in plants obtained by micropropagation. During 35 days of culture, seeds resulted in full plants 14 days earlier than NS, with longer leaves and more roots. Nevertheless, NS plantlets exhibited shoot multiplication. Peaks in O2 consumption and CO2 release were detected at 7 and 14 days for NS and seeds, respectively, suggesting that initial growth has a high energetic requirement. However, the respiration peak was higher in NS than in seeds, possibly due to high energy consumption required for multiple bud breaks. After peaking, respiration decreased, reaching similar values between propagules by 35 days, indicative of an ongoing increase in photosynthesis in both seed and NS plants, possibly due to shoot growth. In conclusion, the development process of NS plants may affect the energy and respiratory demand differently than in seedlings

Keywords:
carbon dioxide; lateral buds; micropropagation; oxygen; respiration