Cryopreservation of in Vitro Grown Axillary Shoot-tip Meristems of Lycium chinense by Vitrification

摘要

In vitro-gtown axillary shoot-tip meristems of Lycium chinense Mill, from cold-acclimated plant were successfully cryopreserved using a vitrification technique. After loading for 15 minutes with a mixture of 2.0 M glycerol and 0.4 M sucrose (20°C), small segments (1-2 mm, 3-4 mm, and 5-6 mm) were cut from axillary buds and exposed to the cryoprotectant solution containing 30% glycerol, 15% ethylen glycol, 15% dimethyl sulfoxide (DMSO), and 0.4 M sucrose at 0°C for 30-120 minutes prior to direct plunge into liquid nitrogen (LN). After rapid thawing (40°C), the segments were washed with MS medium containing 1.2 M sucrose for 0-35 minutes, and then transferred onto recovery-growth medium. The highest survival rate (about 90%) was obtained with cold-hardening treatment, and cryopreserved explants were successfully recovered to plantlets. No abnormal morphological changes were observed with the recovered plants after cryopreservation.