Wang, Q., Department of Virology, Agricultural Research Organization, Volcani Center, Bet Dagan 50250, Israel
Gafny, R., Department of Virology, Agricultural Research Organization, Volcani Center, Bet Dagan 50250, Israel
Sahar, N., Department of Fruit Tree Breeding and Molecular Genetics, Agricultural Research Organization, Volcani Center, Bet Dagan 50250, Israel
Sela, I., Otto Warburg Center for Biotechnology, Virus Laboratory, Faculty of Agricultural, Rehovot 76100, Israel
Mawassi, M., Department of Virology, Agricultural Research Organization, Volcani Center, Bet Dagan 50250, Israel
Tanne, E., Department of Virology, Agricultural Research Organization, Volcani Center, Bet Dagan 50250, Israel
Perl, A., Department of Fruit Tree Breeding and Molecular Genetics, Agricultural Research Organization, Volcani Center, Bet Dagan 50250, Israel

Embryogenic cell suspensions of grapevine (Vitis vinifera L.) were successfully cryopreserved by encapsulation -dehydration and subsequently regenerated into plants. Embryogenic cell suspensions were first-step precultured for 2 days in MGN liquid medium supplemented with increasing sucrose concentrations of 0.25, 0.5, 0.75 and 1 M. Precultured cells were then encapsulated and second-step precultured in MGN liquid medium containing 1 M sucrose for several days. Following preculture, encapsulated cells were dehydrated prior to direct immersion in liquid nitrogen for 1 h. After thawing, cryopreserved cells were post-cultured on MGN medium for survival. Surviving cells were then transferred to different media for regrowth and plant regeneration, respectively. An optimal viability of cryopreserved cells was achieved when encapsulated cells were dehydrated to 20.6% water content and subjected to 2-4 days of preculture on 1 M sucrose. MGN solid medium containing 2.5 g/l AC was found to promote viability of cryopreserved cells. Although cryopreserved cells showed a 5-day lag phase in regrowth, and their increase in fresh weight was only half that of control cells, their growth pattern was the same as that of control cells after two subcultures, following re-establishment in cell suspensions. Cryopreservation promoted embryogenesis and subsequent plant germination, compared with both the control and dehydration treatments. Leaf morphologies of plants regenerated from cryopreserved cells appeared to be similar to those of plants from control cells. © 2002 Elsevier Science Ireland Ltd. All rights reserved.