Shevchenko N. The influence of the cryoprotectants and the regimes of cryopreservation on the integrity of plant shoot-tips

The dissertation work is devoted to studying the cryoprotectants' action and cooling regimes on the integrity of potato and grape shoot-tips. The toxic action of cryoprotectants of amides and diols rows, glycerol and DMSO in different concentrations on shoot-tips, the influence of slow programme freezing, methods of vitrification and ultra-rapid freezing on potato and grape shoot-tips integrity were observed for determination of the dissertation work tasks. It was studied that the least toxic effect had glycerol and 1,2-propanediol in the explored concentrations. The possibility of simplification of the method of slow programme freezing the grape shoot-tips in presence of 1 M DMSO was shown. The influence of cold hardening on the results of potato shoot-tips cryopreservation was studied for the first time. The possibility of using 1,2-propanediol as the cryoprotectant for freezing potato shoot-tips was studied, and perspective of its usage was shown. The perspective of using the modified vitrificationsolution for cryopreservation of potato and grape shoot-tips was shown. The method of ultra-rapid freezing of potato shoot-tips using sterile containers and subcooled nitrogen as heat carrier during freezing was optimised.