DIRECT REGROWTH OF ENCAPSULATED SOMATIC EMBRYOS OF COFFEE (COFFEA-CANEPHORA) AFTER COOLING IN LIQUID-NITROGEN

Somatic embryos of Coffea canephora were successfully cryopreserved after being exposed to a series of preparative steps. 1) Somatic embryos were progressively precultured on media with increasing concentrations of sucrose (03, 0.5, 0.7 and 0.8 M), growing for 3-4 days on each medium. 2) They were then encapsulated in alginate beads that contained 0.5 M sucrose. 3) These beads were dehydrated up to about 13% (FW basis) and plunged into liquid nitrogen. Sixty-three percent of cryopreserved embryos remained alive and about 50% of them grew directly without formation of secondary embryos and calluses. The remaining meristems from cryopreserved material ceased to grow after rooting. This cryogenic procedure appears to be a promising technique for cryopreservation of coffee somatic embryos.