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As part of a comprehensive program for registering and preserving the gene pool of Russian varieties in the VIR genebank, initiated at the N.I. Vavilov All-Russian Institute of Plant Genetic Resources, nomenclatural standards were assigned to potato cultivars ‘Alâska’, ‘Argo’, ‘Bravo’, ‘Irbitskij’, ‘Legenda’, ‘Lûks’, ‘Terra’, and ‘Šah’, and a voucher specimen was prepared for pre-cultivar ‘Bagira’. All of them were bred at the Ural Federal Agrarian Research Centre (Ural Branch of the Russian Academy of Sciences). Nomenclatural standards of these cultivars are preserved in the Nomenclatural standard collection at the Herbarium of cultivated plants and their wild relatives and weeds (VIR Herbarium, WIR). For each of them, a genetic passport was developed using DNA preparations isolated from plant material donated by the cultivar author to the VIR herbarium. The genetic passport, which includes information on the allelic composition of eight chromosome-specific microsatellite loci, is supplemented by the molecular screening data with markers of 11 R-genes for resistance to pests, as well as the data on the types of cytoplasm. The author of cultivars also supplied VIR with samples of virus-free in vitro plants. Microplants of eight Ural cultivars and one pre-cultivar were genotyped using the same SSR markers and included in the VIR in vitro collection, and then in the cryopreservation program. Most of the accessions were characterized by a relatively high, above 39%, level of post-cryogenic regeneration. Frozen explants of the genotyped Ural cultivars (‘Alâska’, ‘Argo’, ‘Legenda’, ‘Terra’, and ‘Šah’) and pre-cultivar ‘Bagira’ were placed for long-term storage in the VIR Cryobank.

In accordance with the International Code of Nomenclature for Cultivated Plants, five nomenclatural standards have been prepared for five potato сultivars1 ‘Alena’, ‘Bylina Sibiri’, ‘Večernij Omsk’, ‘Triumf’, ‘Hozâûška’ bred by the Omsk Agrarian Research Center. Genetic passports were issued to these five cultivars according to the new integrated strategy developed at VIR. According to the strategy, the plant material donated by the author of the cultivars to the VIR Herbarium was used for molecular genotyping. Genetic passports included data of allelic composition of eight chromosome-specific microsatellite loci, markers of different types of organelle DNA, as well as data about diagnostic fragments of 15 markers of 11 R-genes conferring resistance to the most dangerous diseases and pests of potato, namely late blight, nematodes, potato X and Y viruses. Data from genetic passports of five Omsk cultivars were compared to the results of genotyping samples of the same cultivars obtained from different sources. Based on the analysis of pedigrees and genetic passports of these five cultivars, we established the origin of their resistance to harmful organisms.

The effectiveness of breeding is largely depends on the presence of the gene variability in the initial breeding material. The genetic variability assessment helps to evaluate the source material during a fundamentally new forms with economically valuable traits creating. In this regard, the assessment of the genetic polymorphism of the cereal grasses genotypes which are of interest both as a source of breeding material and as a variety candidate was carried out by DNA markers. Seventy-three loci were identified for the Festulolium and Lolium L. genotypes using the SCoT marker system, 69 of markers were polymorphic. This marker system revealed a high level of polymorphism in the studied genotypes of Festulolium and Lolium L. - 94.52%. For the genotypes of intergeneric hybrids of the Agropyron L. genus and their parent forms 90 loci were identified - 46 SCoT markers and 44 SRAP markers. From the total pool of markers 73 markers were polymorphic. On average, the level of polymorphism was 81.1%. For the genotypes of the Alopecurus L. genus interspecific hybrids and their parent forms 157 loci were identified - 52 for RAPD-PCR and 105 - for ISSR-PCR. Of the total pool of markers, 104 were polymorphic According to the results of DNA genotyping the genetic passports of cereal grasses were compiled. [ABSTRACT FROM AUTHOR]

The N.I. Vavilov All-Russian Institute of Plant Genetic Resources (VIR) is developing new approaches to documentation of national cultivars, taking into account recommendations of the International Code of Nomenclature for Cultivated Plants in parallel with methods of genetic certification. The nomenclatural standard of a particular cultivar represented by a herbarium specimen can be used as a reference for verifying authenticity and uniformity of cultivar specimens obtained from various sources. The verification requires fast and reliable methods for cultivar genotyping. This paper presents protocols for modified methods of DNA extraction, PCR-analysis and SSR-genotyping, which allow potato cultivars identification without the use of expensive reagent kits. A set of ten chromosome-specific microsatellite markers was used to study polymorphisms in 66 modern Russian potato cultivars, as well as in 11 pre-cultivars and breeding clones, represented by nomenclatural standards and voucher specimens, respectively. This subset of 77 specimens has demonstrated a high level of polymorphism in ten studied microsatellite loci. The SSR analysis identified 73 alleles; 7.3 alleles per locus were observed on average, the number of which varied from 3 (STG0025 locus) to 11 (locus StI046). The PIC values varied from 0.544 (STG0025 locus) to 0.836 (StI046 locus). The alleles, unique for this subset, were found at six studied loci. The high level of polymorphism at the SSR loci made it possible to unambiguously identify almost every cultivar, with the exception of the expected coincidence of microsatellite profiles of two cultivars, which are somaclonal variants. Using an optimized set of eight microsatellite markers, the genetic relationships of modern Russian potato cultivars were studied.

VIR is creating a collection of nomenclature standards for cultivars of different crops in line with the provisions of the International Code of Nomenclature for Cultivated Plants (ICNCP). The nomenclatural standards are designed in the form of a herbarium sample in cooperation with the authors of cultivars, who select plant material for each cultivar in the experimental field of their organization and forward it to the scientific herbarium together with the accompanying documents. Registering of herbarium specimen in the scientific herbarium is followed by the publication of nomenclatural standards. The article presents a new VIR genebank strategy for registering plant material of domestic cultivars received from breeders, which includes the design of nomenclatural standards; the development of a genetic passport of a cultivar using DNA samples from the plant delivered to the scientific herbarium; and application of biotechnological methods for keeping explants (isolated from the acquired plant material as buds or meristems) alive. The proposed integrated approach makes it possible to document cultivars not only with the help of nomenclatural standards, but also with the use of molecular-genetic methods, as well as to save genotyped specimens, transferred to herbarium, in in vitro and in cryo collections. This approach is applicable to any vegetatively propagated crop. The article summarizes the first results of our proposed strategy using modern domestic potato cultivars as an example. Collection, transfer and preparation of plant material for nomenclatural standards of potato varieties are specific; this article explains our protocol for this work. The implementation of this strategy in 2018-2020 led to the designation of nomenclatural standards for 66 Russian potato varieties and elaboration of their genetic passports, which are presented in a series of articles included into issues Nos.3 and 4, Volume 3, of the journal “Plant Biotechnology and Breeding”, containing an overview of methodological approaches to registration of modern domestic cultivars in the VIR collection. DNA samples obtained from the plant material provided by the cultivar authors for nomenclatural standard designation will continue to be used as a source of information on the genetic potential of a cultivar through the expansion of the list of DNA markers and the application of new genetic technologies.

Enrichment of genetic diversity by means of somaclonal variation can allow selection of individuals with increased adaptability to various unfavorable conditions. Twenty shoot cultures differing in organogenesis and morphological features were selected for two studied clones. Multilocus genetic passports of somaclonal lines were developed according to RAPD analysis. Among the samples derived from clone № 52-84/8 shoot cultures the changes in RAPD-spectra were detected over primers UBC-106 and UBC-254. In the case of clone № 6-161/3 the same changes were detected over primers UBC-268 and UBC-154. UBC-203 primer didn’t show any variation.

New trends in molecular medicine that have emerged owing to the success of the national Human Genome program are characterized. The major attention is paid to molecular diagnostics, preventive medicine, and gene therapy. Preventive medicine is a product of synthesis of the current notions on genetics and biochemistry of human diseases; it comprises pharmacogenetics, presymptomatic diagnosis, and testing of genes of predisposition to the most frequent multifactor diseases. In the Gene Therapy section, advantages and drawbacks of the main methods of delivery of nucleic acids into the cells are considered; diseases that are attempted to be rectified using gene therapy are listed. Exemplified with Duchenne myodystrophy, the problems encountered in correction of a genetic defect with the aid of foreign genes are considered. Results are summarized for assessing the efficiency of various methods of introduction of dystrophin cDNA (gene gun, liposomes, microspheres, viral oligopeptides, and lactoferrin) conducted on the Duchenne myodystrophy model, mdx mice. [ABSTRACT FROM AUTHOR]