In Vitro Floral Emergence and Improved Formation of Saffron Daughter Corms

Abstract

In vitro cormogenesis is a potential tool for improving saffron production under controlled conditions. In this study, the effects of explant type, culture type, and medium supplements on saffron daughter corm formation in vitro were assessed. Saffron flowers emerged 30 days after culture, and the sizes of in-vitro- and ex-vitro-produced flowers and stigmas were similar. In vitro daughter corm formation and the saffron life cycle was completed after 10 and 14 weeks of culture, respectively. Using in vitro intact corms was more effective for corm production than using apical buds. Compared with apical bud explants, mother corm explants produced more corms with a higher fresh weight and diameter. Compared with solid culture, liquid cultures using bioreactors provided corms with a higher fresh weight and diameter, regardless of explant type. An ebb and flow system provided the highest cormlet fresh weight and diameter but the fewest cormlets, whereas an immersion system provided more cormlets with a smaller size. Saffron apical buds cultured with salicylic acid at 75 mg L−1 or glutamine at 600 mg L−1 exhibited the highest cormlet diameter and fresh weight. These findings will improve the process of in vitro cormogenesis and the production of saffron under controlled conditions.