Cryopreservation is the most suitable long-term storage method for genetic resources of vegetatively maintained crops like potato. In the Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) the DMSO droplet method is applied, and so far more than 1000 accessions are cryopreserved with an average regeneration rate of 58%. New experiments with four potato accessions using alternating temperatures (22/8°C day/night temperature, 8 h photoperiod, 7 d) prior to cryopreservation showed improved regeneration. The influence of this preculture on the shoot tips was studied for two wild, frost resistant species Solanum acaule and S. demissum and for two cultivated, frost sensitive potatoes S. tuberosum 'Désirée' and 'King Edward'. Comparison of liquid and solid media after cryopreservation showed improved regeneration on solid media with higher regeneration percentages, less callus formation and better plantlet structure. In comparative analyses biochemical factors like soluble sugars, starch, and amino acid concentrations were measured. Shoot tips after constant and after alternating temperature preculture were analyzed. Total concentrations of soluble sugars (glucose, fructose, and sucrose) were higher for all accessions after the alternating temperature preculture, which could be the reason for improved cryopreservation results.Keywords Solanum tuberosum Á Solanum acaule Á Solanum demissum Á DMSO droplet method Á Carbohydrates Á Amino acids Abbreviations CT Constant temperature preculture (22°C constant temperature 7 days) AT Alternating temperature preculture (22/8°C day/night temperature 7 days)

The germplasm collections of the Vavilov Institute of Plant Industry, Russia represent the first germplasm collection made for potatoes, now numbering 8,680 accessions. It has tremendous historical and practical importance and a rich history, having been used to document a polyploid series in the cultivated species, to formulate initial taxonomic hypotheses in potato, for studies of interspecific hybridization, and serving as the germplasm base for Russian breeding efforts. Despite its importance and size, there has never been a study of its molecular diversity, and there were many gaps in its passport data. The purpose of the present study is to obtain morphological, ploidy, and microsatellite (SSR) data needed to set up a useful subset of the collection of cultivated potatoes and closely related wild species, Electronic supplementary material The online version of this article (and to use this collection to study cultivated potato taxonomy and phylogeny. Through assessments of viability, passport data, and chromosome counts, we selected a subset of 238 cultivated and 54 wild accessions. A morphological and nuclear SSR study of these collections distinguished only three cultivated species: Solanum curtilobum, S. juzepczukii and S. tuberosum, not the many more cultivated potato species of prior taxonomic treatments. The SSR study supports the ideas of S. acaule as one of the parental species for S. curtilobum and S. juzepczukii. The morphological and SSR results are very similar to other recent studies of cultivated species, and show the need to reclassify the collection of cultivated potatoes by modern taxonomic criteria.

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Cereal crops, such as oats and barley, possess a number of valuable properties that meet the requirements for functional diet components. This review summarized the available information about bioactive compounds of oat and barley grain. The results of studying the structure and physicochemical properties of the cell wall polysaccharides of barley and oat are presented. The main components of the flavonoids formation pathway are shown and data, concerning anthocyanins biosynthesis in various barley tissues, are discussed. Moreover, we analyzed the available information about structural and regulatory genes of anthocyanin biosynthesis in Hordeum vulgare L. genome, including β-glucan biosynthesis genes in Avena sativa L species. However, there is not enough knowledge about the genes responsible for biosynthesis of β-glucans and corresponding enzymes and plant polyphenols. The review also covers contemporary studies about collections of oat and barley genetic resources held by the N.I. Vavilov All-Russian Institute of Plant Genetic Resources (VIR). This review intended to provide information on the processes of biosynthesis of biologically active compounds in cereals that will promote further researches devoted to transcription factors controlling expression of structural genes and their role in other physiological processes in higher plants. Found achievements will allow breeders to create new highly productive varieties with the desirable properties.

Conservation of plant genetic diversity, including economically important crops, is the foundation for food safety. About 90 % of the world’s crop genetic diversity is stored as seeds in genebanks. During storage seeds suffer physiological stress consequences, one of which is the accumulation of free radicals, primarily reactive oxygen species (ROS). An increase in ROS leads to oxidative stress, which negatively affects the quality of seeds and can lead to a complete loss of their viability. The review summarizes data on biochemical processes that affect seed longevity. The data on the destructive effect of free radicals towards plant cell macromolecules are analyzed, and the ways to eliminate excessive ROS in plants, the most important of which is the glutathioneascorbate pathway, are discussed. The relationship between seed dormancy and seed longevity is examined. Studying seeds of different plant species revealed a negative correlation between seed dormancy and longevity, while various authors who researched Arabidopsis seeds reported both positive and negative correlations between dormancy and seed longevity. A negative correlation between seed dormancy and viability probably means that seeds are able to adapt to changing environmental conditions. This review provides a summary of Arabidopsis genes associated with seed viability. By now, a significant number of loci and genes affecting seed longevity have been identified. This review contains a synopsis of modern studies on the viability of barley seeds. QTLs associated with barley seed longevity were identified on chromosomes 2H, 5H and 7H. In the QTL regions studied, the Zeo1, Ale, nud, nadp-me, and HvGR genes were identified. However, there is still no definite answer as to which genes would serve as markers of seed viability in a certain plant species.