This study aimed at developing in vitro propagation methods for Crocus sativus L., focusing on the effectiveness of temporary immersion systems (TIS) or bioreactors as an alternative, cost-efficient technique for the large-scale production of saffron corms. The effects of the culture system and cross-cutting on saffron propagation were evaluated. Saffron shoots were cultured in TIS and compared with shoots produced using a conventional semi-solid tissue culture system (SS). The recipient material for automated temporary immersion used in this study was the SETIS™ bioreactor. The growth parameters measured for in vitro culture were the number of neo-formed shoots, shoot height, and the number and size of corms. Based on the present detailed study, the highest shoot multiplication rate (9.1 shoots/explant with 7.2 cm of shoot height) was achieved in the TIS system after shoot cross-cutting, while the lowest multiplication rates were obtained in the semi-solid system (1 shoot/explant with 14.8 cm long shoots). Furthermore, the highest corm formation was obtained in the TIS system, with an average of four corms per explant, with a larger corm weight (10.90 g) and diameter (21.78 mm). These findings highlighted for the first time the efficiency of the bioreactor system combined with cross-cutting of the shoot for efficient and scalable saffron corm propagation, thus making a valuable contribution to sustainable cultivation and conservation strategies while meeting the growing demand for this spice.
Merzougui et al. (Thu,) studied this question.