SOME MECHANISMS OF CRYOINJURIES IN PLANT-CELLS IN-VITRO AND CHARACTERISTICS OF THEIR CRYOPRESERVATION

The present review treats characteristics of plant cells and their cul tures in vitro important for the procedure of their cryopreservation, the only means of preserving cell strains, tissues, and microorgans fo r an unlimited length of time. It is difficult to overestimate the urg ency of the task of reliably preserving actively metabolizing plant ce lls in unaltered condition; since cell strains are already replacing n atural plant raw material at biotechnological factories, cultured tiss ues make it possible to obtain somaclonal variants (a new source of ge netic diversity for plant breeding), and embryoids-especially apical m eristems-ensure regeneration of plants that are exact copies of the or iginals. Cryopreservation thereby becomes a means of preserving not on ly the gene pool of cultured cells, but also the gene pool of vegetati vely propagating and other plants as well. Published data and data of our own on processes involved in cryoinjury to actively metabolizing c ells are discussed in the review. This analysis shows that the plasmal emma is the main target of cryoinjuries, changes of it being associate d with disturbance of continuous structure of its lipid bilayer. Also discussed briefly are certain ways of weakening cryoinjuries that have been used at the K. A. Timiryazev Institute of Plant Physiology, Russ ian Academy of Sciences.