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This is an overview of contemporary published works dedicated to the ability of soybean plants to regenerate in vitro and the techniques to achieve high regeneration rates, which is a necessary condition for the inclusion of soybean genotypes in genome editing programs. The main factors that determine the regenerative capacity of explants from various soybean accessions are considered. The greatest effect on the efficiency of regeneration is exerted by the conditions of in vitro culture initiation, type of explant, composition of the nutrient medium, shelf life of seeds, and genotypic characteristics of soybean accessions.

Background. VIR’s potato collection is one of the oldest and richest; however, it is constantly exposed to viruses that negatively affect useful agronomic properties of tubers. Close monitoring of the phytosanitary state of potato accessions helps to select the most effective method of therapy for subsequent healing of infected plants and obtaining high-quality planting material.Materials and methods. The research was aimed at improving the health of 18 varieties of Solanum tuberosum L. from the VIR collection. Testing for the presence of viruses was based on the ICA and RTPCR techniques, and the consequent healing was performed using the methods of meristem culture and cryotherapy.Results and conclusions. During the field test of potato plants, PVX, PVS and PVA were found to be the most common viruses. PSTVd was completely absent in all tested accessions. The effectiveness of in vitro healing of potato plants from viruses was assesses using meristem culture. The percentage of healed plants was 0% for PVS, 0% for PVX, 33.4% for PVA, 50% for PLRV, 72.3% for PVY, and 83.4% for PVM. Healing with meristem culture was shown to be the most effective against PVY and PVM. While assessing the effectiveness of post-cryogenic restoration of potato microplants, the level of post-cryogenic regeneration of the shoot tips in potato microplants was determined at 22.3% on average for a sample. The minimum was observed in k-16762 ‘Sagita N’ (5%), and the maximum in k-1378 ‘Marta’ (41.7%). Analysis of the effectiveness of potato recovery from viruses by in vitro cryotherapy showed that the percentage of recovered plants was 100% for PVY, 100% for PVA, 88.9% for PVM, 77.8% for PVS, 44.4% for PVX. Thus, the techniques of apical meristem culture and cryotherapy proved to be effective against PVY, PVA and PVM viruses. However, in the case of multiple infections, it is necessary to combine elements of different healing protocols to increase the effectiveness of the healing procedure.

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.