BIT^® bioreactor increases in vitro multiplication of quality shoots in sugarcane (Saccharum spp. variety LAICA 04-809)

The multiplication of sugarcane (Saccharum spp.) variety LAICA 04-809 by direct organogenesis was evaluated using four cultivation systems: (1) the traditional system which uses a semisolid medium and (2) three temporary immersion systems with liquid medium (RITA^®, BIT^®, and SETIS™). In addition, three planting densities (10, 30, and 50 mL of medium per explant) were studied for each system as initial inoculum. Sucrose consumption was observed in all temporary immersion systems after 4 weeks of culture. Photomixotrophic metabolism was identified in all three temporary immersion systems evaluated (RITA^®, BIT^®, and SETIS™). In addition, at density of 30 mL medium/explant, the BIT^® bioreactor generated the highest number of quality shoots (425.33 ± 24.58). No hyperhydricity was observed in the explants. In TISs, the 50 mL volume of medium per explant obtained the highest multiplication coefficient (RITA^® 25.53 ± 11.42, BIT^® 20.08 ± 4.1 and SETIS™ 11.47 ± 1.27). The results of this study suggest that the combination of the BIT^® system with the 50 mL volume of medium/explant represents the best conditions for mass propagation of sugarcane shoots after four weeks of cultivation.