Use of temporary immersion bioreactors on in vitro culture of cactus pear

This work was conducted with the objective of evaluating the performance of cactus pear cultivars on in vitro culture using bioreactors and the conventional method. The treatments were arranged in a 3 × 2 factorial scheme with a completely randomized design, and the three cactus pear cultivars (Orelha de elefante mexicana, Miuda and IPA-Sertânia) were combined with two micropropagation methods (conventional and temporary immersion bioreactors), totaling six treatments with five replicates each. After 30 days, the following variables were evaluated: cladode length, fresh explant matter mass, number of shoots and number of roots. There was a significant interaction between the cultivar factor and the micropropagation method for the cladode length and fresh matter mass, with bioreactors being the most responsive. However, regarding to the number of shoots and number of roots, there was no interaction between these factors under the same level of significance, where the conventional crop stood out. The results indicate different morphogenetic responses among the tested cultivars, and specific in vitro propagation protocols should be developed for each one. Key words: Micropropagation, bioreactor, plant productivity, cactus pear cultivars.