Somatic embryo proliferation, maturation and germination in Catharanthus roseus

In the present study an efficient somatic embryogenesis method has been developed in Catharanthus roseus. Friable embryogenic callus was induced from hypocotyl of in vitro germinated seeds on Murashige and Skoog basal nutrient media supplemented with various auxins particularly 2,4-D (1.0 mg l-1). However, only NAA (1.0 mg l-1) produced somatic embryos in cultures. Embryo proliferation was even high on the same medium added with BAP. Cotyledonary somatic embryo germinated and converted into plantlets in BAP (0.5 mg l-1) added medium following a treatment with gibberellic acid (1.0 mg l-1) for maturation. Carbon sources and concentrations had a marked influence on maturation process. Plantlet conversion was better achieved when embryos were matured on 3% fructose or 3-6% maltose. The result discussed in this paper indicates that somatic embryos were produced in numbers and converted plantlets can be used as raw material, genetic modification to embryo precursor cell may improve alkaloid yield further.