Improvement in the production of micropropagated seedlings of Paliavana sericiflora Benth: an endangered species

This study focused on the species Paliavana sericiflora Benth., considered vulnerable to extinction. The species is endemic to Campo Rupestre Ferruginoso habitats, which are geosystems with specific soil and climate characteristics that result in a flora that is strictly adapted to these conditions. Due to the importance of conservation of the species and the need to produce seedlings for the establishment of germplasm banks, the objective of this study was to investigate the effect of active chlorine on seed disinfection, the best source of carbohydrates and the use of gas exchange systems in the in vitro culture of P. sericiflora. The seeds were immersed for different times in sodium hypochlorite (NaOCl, 1.00–1.25% active chlorine) for disinfection and exposed to different gas exchange systems and carbohydrate concentrations during in vitro multiplication. In the elongation and rooting stages, different systems for gas exchange with the external environment were tested. The results indicated that immersion of seeds in active chlorine for 10 min was effective in obtaining the largest number of germinated plants free of contamination. Supplementation of 30 g L⁻¹ sucrose to the culture medium promoted greater bud sprouting during multiplication. The use of one membrane favoured the growth and emergence of new shoots. The mini-incubator system was considered efficient for acclimatization, favouring the production of micropropagated P. sericiflora plants.