Abstract: Abundant embryogenic calli were induced from young roots and hypocotyls of hybrid papaya (Carica papaya L. ) on modified MS medium. After the calli were subcultured in liquid medium, a large number of somatic embryos were obtained. The different classes of cells were separated by screening the suspension through meshes of different sizes, a filtration step which served to synchronize somatic embryo development, thus, about 70% synchronous mature embryos were obtained. After desiccated to 50%--70% of water, dry somatic embryos were encapsulated in modified sodium alginate system which was composed of a mixture of sodium alginate with cellulose derivative A. The conversion rate of artificial seeds reached 80% under sterile condition and the survival rate of seedlings reached 72 % after they were transplanted to the field where the plants blossomed and yielded fruits normally.

Key words: Artificial seed, Desiccation and storage, Embryogenesis, Papaya