Evaluation of different temporary immersion systems (BIT®, BIG, and RITA®) in the micropropagation of Vanilla planifolia Jacks

The cultivation of Vanilla planifolia is of great economic importance because vanillin, a chemical valued in the food and cosmetics industry, is extracted from its pods. The conventional propagation of this plant is limited by the low viability of its seeds and the very low germination rate. For this reason, in vitro micropropagation techniques using temporary immersion systems (TIS) represent an alternative propagation mechanism. This work assessed three different bioreactor systems in two different micropropagation phases (multiplication and rooting) of V. planifolia: Temporary Immersion Bioreactors (BIT®) , Gravity Immersion Bioreactors (BIG), and Recipient for Automated Temporary Immersion (RITA®). A higher number of shoots/explant were observed in the multiplication phase in BIT® systems (18.06 shoots/explant), followed by RITA® (12.77) and BIG (6.83). In the rooting phase, a higher number of longer roots were obtained in BIT® compared with BIG and RITA®. However, higher chlorophyll content was observed in BIG, followed by RITA® and BIT®. A 100% survival was obtained in vitro micropropagated plantlets in BIT®, exceeding the survival rate observed in RITA® and BIG. In general, our findings confirm the utility of BIT® systems in the optimization of the commercial micropropagation of this species. Furthermore, this system reduces the costs associated with the use of RITA® systems.