CRYOPRESERVATION OF WALNUT SOMATIC EMBRYOS

In the present work, cryopreservation of 1-2mm isolated walnut somatic embryos was achieved after preculture on DKW medium supplemented with 5% DMSO and 0.5% proline, plasmolysis on DKW medium containing a prog ressive concentration of sucrose up to 1M and dehydration under lamina r air flow. Thermal analysis performed on somatic embryos, both naked and encapsulated in calcium alginate beads, showed the necessary dehyd ration time (1.5h or 3h respectively) to get vitrification on cooling and rewarming. The regrowth expressed by the capacity to produce new e mbryos is highly variable. The factors affecting the success of somati c embryo cryopreservation are discussed.