Cryopreservation of auricula shoot tips using the encapsulation/dehydration technique

Calcium alginate encapsulated, in vitro culture derived shoot tips of the florist's auricula, cultivar Embley, were successfully cryopreserved using the encapsulation/dehydration technique. The use of preculture media containing both sucrose and mannitol was essential for post-thaw growth. After 2 weeks cold acclimatisation at 10 degrees C, shoot tips were encapsulated and incubated in culture medium containing 0.25 M sucrose and 0.25 M mannitol for 48h, followed by 23h dehydration with silica gel (water content of beads approximately 16%) prior to plunging into liquid nitrogen. Post-thaw growth of the shoot tips was without callus formation. The morphology of frozen and non-frozen shoots was comparable.