Effects of Osmolytic Agents on Somatic Embryogenesis of Saffron (Crocus sativus L.)

Abstract

A protocol for callus induction from meristem tissues and subsequent somatic embryo formation were established in this study. Explants were taken from apical and lateral meristems of saffron and these explants were cultured on MS medium supplemented with combinations of 2.4-dichlorophenoxyacetic acid (2.4-D) and Kinetin (Kn). The effects of osmotic agents such as abscisic acid (ABA), polyethylene glycol (PEG) and Gelrite on somatic embryogenesis were also investigated. After 45 and 60 days of culture, calli were induced from apical and lateral meristems, respectively. The apical meristems yielded higher quality calli when compared to the lateral meristems. The highest frequency of callogenesis and the growth rate of callus were achieved from apical meristems on Murashige and Skoogs (MS) medium supplemented with 2.4-D (2 mg/l) and Kinetin (0.5 mg/l). After 45 days of subculture, the segments of nodular calli were transferred to plant growth regulator (PGR)- free media for induction of pre-embryogenesis embryo formation. Pre-matured embryos were cultured on MS medium supplemented with different osmotic agents such as Gelrite, ABA and PEG to study their effects on embryo maturation. Both PEG and ABA proved more effective for somatic embryo maturation as compared to Gelrite.