Micropropagation of Vanilla planifolia using the Biotilt™ temporary immersion system

Abstract Vanilla planifolia Jacks. ex Andrews is an orchid species of great economic importance is responsible for the production of fruits rich in vanillin and has a high global demand. Conventional propagation has limitations for production and contributes to pressure on natural populations. In this context, tissue culture emerges as a viable strategy for clonal propagation of Vanilla, and temporary immersion bioreactor systems stand out by offering greater efficiency, sustainable management, and conservation potential for the species. The objective of this study was to evaluate the efficiency of the Biotilt™ bioreactor system compared to the conventional semi-solid system and to identify the best adjustments of immersion frequency and medium volume to optimize the in vitro multiplication of V. planifolia explants. Two experiments were conducted. The first experiment assessed the morphophysiological performance of explants cultivated in Biotilt™ (liquid medium) versus the semi-solid system, considering growth variables, physiological quality, efficiency indices, and correlation analysis. The second experiment investigated combinations of medium volume and immersion frequency in Biotilt™ in a factorial design, aiming to optimize culture conditions. Results indicated that Biotilt™ promoted higher explant length, number of shoots, leaves, and roots, as well as higher chlorophyll content, thus demonstrating greater multiplication and physiological efficiency. The analysis of composite indices reinforced the superiority of the temporary immersion system for explant development. Finally, although not statistically significant, the tested combinations of volume and immersion frequency maintained a positive performance trend, contributing to future protocols. These results highlighted the potential of Biotilt™ as an efficient alternative for the micropropagation of V. planifolia , combining increased productivity with conservation practices.