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The main biological feature of potato varieties is vegetative reproduction. This mode of reproduction can be associated with problems due to the physiological ageing of the crop and the accumulation of specific pathogens causing reduced tuber yields. In order to avoid these problems, potato seed production widely uses modern biotechnological methods. The use of meristemic technologies allows preserving the identity of the biomaterial in the process of maintaining the potato collection in vitro, but even under these conditions there is a threat that modifications of individual economically valuable traits may get fixed. In potato varieties, such non-heritable deviations manifest themselves in the form of a shift in phenophases and the period of tubers ripening. The use of modern high-tech methods of varietal resources storage implemented on the basis of biotechnological approaches, makes it possible to maintain high quality of biomaterial. At the same time, mobility and practicality remain the main criteria for the effectiveness of different storage methods, depending on the extent to which they can be used in practice. In this review, the collection of varieties at Russian Potato Research Center is used as an example for considering the main stages of the formation and functioning of a modern Bank of Healthy Potato Varieties (BHPV), which supplies various regions of the Russian Federation with high-quality phytopathogen-free potato varieties.

Cryopreservation provides long-term storage of the gene pool of potato varieties in cryobanks at extremely low temperatures. Currently, droplet vitrification is the most widely used method for cryopreservation of potato varieties, which is constantly improving to increase the regeneration rates of the stored plant material. Different modifications of this method are used in the world’s leading potato genebanks. This paper presents the results of studying the effect of cultivation conditions after plunging into liquid nitrogen and thawing of shoots tips and axillary buds of in vitro plants on their postcryogenic recovery. The droplet-vitrification method modified at VIR was used for cryopreservation. The factor “prolonged dark incubation of explants” did not have a significant effect on the frequency of post-cryogenic regeneration of the studied varieties except for one variety (Krepysh), for which a significant increase in the regeneration rate was observed for the shoot tips cultivated in the darkness compared to the cultivation under the photoperiod 16/8 hours (light/darkness). The frequency of post-cryogenic regeneration of shoot tips was higher than that of the axillary buds for all varieties; however, these differences were significant (p < 0.05) only in two cases: for the variety Udacha (a photoperiod of 16/8 hours) and for the variety Krepysh (the dark incubation). The results of two-factor analysis of variance indicate that there is no effect of interaction of factor 1 (prolonged dark incubation) and factor 2 (explant type) on the ability of varieties to post-cryogenic recovery. Taking into account the obtained results, the further cryopreservation of an extended subset of 9 varieties was carried out using shoot tips, which, after freezing-thawing, were cultivated under the photoperiod of 16/8 hours. The frequency of post-cryogenic regeneration of these varieties varied from 30 to 60 %. A significant effect of genotype on postcryogenic recovery has been established. The ability of varieties to regenerate shoots after freezing and thawing was not related to the values of morphogenic indices of in vitro plants. The age of the meriklons (2–4 years) did not significantly affect either the morphogenic indices or the frequency of post-cryogenic regeneration.

The formation of potato microtubers in vitro is discrete, and in order to increase its efficiency, it is important to ensure a regular supply of nutrients in a sterile vessel during plant ontogenesis. The aim of the research was to study the effect of phytohormones kinetin and IAA on the formation of microtubers in 20 potato varieties of different ripen time using two compositions of liquid media MS with 2% and 8% sucrose in the process of plant ontogenesis. The biomaterial was grown in plastic containers, the design of which allows the exchange of the nutrient medium in different phases of plant growth. The ontogeny of plants in tissue culture was significantly influenced by the ripening period of varieties. The early varieties were characterized by more intensive growth, their multiplication factor was 1.1-1.7 times higher than that of the middle early and mid-season varieties. The introduction of 0.4 mg/l kinetin into the nutrient medium had a positive effect on the formation of microtubers. For early varieties, the number of formed microtubers per plant increased by 1.2-1.8 pcs. compared to a hormone-free environment. The excess in later varieties was 0.8-0.9 pcs. per plant. The use of IAA without the addition of kinetin did not increase the number of microtubers. Complex application of phytoharmones promoted the growth of the fractional composition. [ABSTRACT FROM AUTHOR]