INJURIES TO THE PLASMALEMMA OF GINSENG CELLS DURING CRYOPRESERVATION

We investigated the relationship between survival of cells of Asiatic ginseng suspension culture (Panax ginseng Mey) after freeze-thaw treat ment, cryotolerance and osmoresistance of the plasmalemma, and content of intracellular sugars. A 1.6-fold rise of sugar content in the cell s and 2.3-fold increase of their survival occur in the process of hard ening (21 days) with increase of sucrose concentration in the medium f rom 3 to 20%. Culture dry mass increases 1.7-fold during the lst week of hardening (at 12-degrees-C), but then remains unchanged (at 2-degre es). On the other hand, the ratio of dry to raw mass increases (1.6-fo ld) until the end of hardening. Ginseng cells hardened at constant (3% ) sucrose concentration in the medium exhibit a 1.8-fold decline in co ntent of endogenous sugars at the end of the 2nd week of hardening, su rvival, culture dry mass, and its ratio to raw mass remaining constant here. The fluorimetric method reveals an almost complete correlation between cryotolerance and osmoresistance of ginseng cells. A pool of c ells resistant to ultralow temperatures remains in the cell population below -40-degrees. Their number in culture hardened with increase of sucrose concentration in the medium is twice as great as the number of such cells in unhardened culture. Osmotic stress associated with stro ng cell dehydration plays a decisive role in injuries to the plasmalem ma. It is hypothesized that three types of osmotic injuries to the pla smalemma exist in cells of Asiatic ginseng suspension culture.