In vitro growth of Melaleuca alternifolia Cheel in bioreactor of immersion by bubbles

Development of new techniques for in vitro culture is necessary to optimize and reduce the production costs. The aim of this work was to introduce the bioreactor BIB® (Bioreactor of Immersion by Bubbles)and compare it with conventional culture and bioreactor RITA® (Recipient with Automatized Temporary Immersion)for In vitro growth of M. alternifolia plantlets. Plantlets with 1.0 cm height from the fifth In vitro subculture were used. Treatments were: (1)conventional culture (control)using 200 mL glass flasks covered with polypropylene lids; (2)bioreactor RITA® and (3)bioreactor BIB®. Continuous immersion and aeration was used in bioreactors. It was used liquid MS medium supplemented with 30 g.L-1 sucrose and 1 drop.200 mL-1 Tween 20® (i.e. detergent for bubbles formation). BIB® obtained best results for total fresh mass (0.39 g)and shoot fresh mass (0.27 g), fresh mass increment (3.1), total dry mass (0.036 g)and shoot dry mass (0.033 g)than RITA® and conventional culture. In conclusion, BIB® is more efficient to the biomass accumulation of M. alternifolia plantlets.