PLANT-REGENERATION FROM PROTOPLASTS OF EMBRYOGENIC CELL-SUSPENSIONS OF COFFEA-ARABICA L CV CATURRA

Coffee plants were regenerated from protoplasts isolated from embryogenic cell suspension cultures derived from somatic embryos of Coffea arabica L. cv. caturra. Yields of viable protoplasts ranged from 1 x 10(5) protoplast/g fresh weight. Protoplast preparations usually contained no contaminating cells, and when present, the number of cells never exceeded 0.1% of the total. Plating efficiencies of protoplast ranged from 1 to 10%. Embryogenic protocolonies obtained after several subcultures in a medium supplemented with 0.5 mg/l each benzylaminopurine, 2,4-dichlorophenoxyacetic acid and naphtaleneacetic acid, were transferred to a medium lacking plant growth regulators. Well differentiated embryos were formed in selected protocolonies that contained many embryos-like structures. Approximately 70% of the somatic embryos developed into green rooted plantlets which were successfully transferred to vessels containing sterilized scoria. Plants grown for two months in scoria were finally transferred to greenhouse.