Somatic Embryogenesis in In Vitro Culture of Leucojum vernum L.

Procedures for somatic embryogenesis (SE) in in vitro culture of spring snowflake have been developed from different types of explants like scales and leaves isolated from bulbs, ovaries and fruits. Various plant growth regulators were tested including a cytokinin – benzyladenine (BA) and various concentrations of the exogenous auxins 3,6-dic hloro-2-methoxybenzoic acid (Dicamba), 2,4-dichlorophenoxyacetic acid (2,4-D) or 4-amino-3,5,6-trichloropicolinic acid (Picloram). Fruit explants, cultured on medium containing Picloram and BA, ensured the highest percentage of callusing and such calli were most efficient in inducing somatic embryos. The addition of abscisic acid (ABA) in combination with polyethylene glycol (PEG) stimulated somatic embryo maturation. Torpedo-stage embryos developed into plants in the presence of BA and 1-naphthaleneacetic acid (NAA). The formation and growth of adventitious bulbs required that the plantlets be chilled at 5�C in the dark for 6 weeks. After chilling, the bulbs grew well in darkness 25�C. High sucrose concentration in the medium was necessary for obtaining large bulbs.