Light and sucrose regulate in vitro growth and acclimatization of ‘Turiaçu’ pineapple

Abstract ‘Turiaçu’ is a pineapple variety native to the Amazon region with high commercial potential that remains unexplored. Its propagation traditionally relies on vegetative material from mother plants, which increases the risk of pathogen transmission. Temporary immersion bioreactors (TIBs) are an alternative for large-scale production of disease-free plantlets, but their efficiency depends on the optimization of culture conditions. This study aimed to evaluate the effects of photoautotrophic and photomixotrophic in vitro cultivation of ‘Turiaçu’ pineapple under different light intensities in TIBs, as well as the subsequent ex vitro acclimatization performance of the plants. Explants were cultivated under light intensities of 71 and 116 µmol m⁻² s⁻¹, in culture media containing 0–15 g L⁻¹ of sucrose. After 50 days of in vitro growth, biometric parameters, photosynthetic pigments, gas exchange, and leaf anatomy were evaluated. Following 30 days of ex vitro acclimatization, survival, growth, and physiological performance were analyzed. The presence of sucrose in the culture medium was the main factor influencing growth and photosynthetic performance. Photoautotrophic conditions stimulated photosynthetic capacity, whereas photomixotrophic cultivation promoted greater biomass accumulation, particularly under 71 µmol m⁻² s⁻¹. Both cultivation modes resulted in 100% survival after acclimatization, confirming the high physiological quality of the in vitro-derived plants. Overall, the combination of 15 g L⁻¹ sucrose and a light intensity of 71 µmol m⁻² s⁻¹ proved to be the most suitable condition for large-scale production of ‘Turiaçu’ pineapple plantlets in temporary immersion bioreactors.