Fungal contamination of 17 winter wheat varieties grown in the Krasnodar region under the natural infections was analyzed. In addition to the traditional mycological analysis of infection with fungi, methods based on the quantitative detection of metabolites inherent in fungi and absent in the host plant were used. For this purpose, the ranges of DNA contents of Alternaria, Fusarium and Microdochium fungi, as well as mycotoxins produced by these fungi were characterized in the grain. Abundant presence of Alternaria fungi was detected without a significant difference between the varieties. A quantitative detection of the Microdochium fungi in grain was carried out at the first time in Russia and it was shown that the content of M. nivale DNA was significantly exceeds the content of M. majus DNA. The dominant of F. graminearumin the complex of Fusarium fungi in comparison to other species and the significant range of the content of the metabolites produced by this pathogen were shown. The high variation of contents of marker metabolites inherent in highly aggressive species of fungi and the stability of these parameters for saprotrophic organisms can be of fundamental importance in the selection of objective for quantitative measurements of plants resistant to pathogens. The maximum amount of F.graminearum metabolites was found in the grains of susceptible Brigada. The minimum content of Fusarium metabolites was established in the grain of Adel and Kurs varieties, which are the relatively resistant to pathogenic Fusarium fungi. The proportion of F.graminearum DNA as a percentage of the DNA of Fusarium group forming trichothecene mycotoxins ranged from 6.1% to 100.9%. This value is an indicator of plant resistance to infection by pathogens. According to our observations, values above 30% are characteristic of susceptible varieties. A positive correlation was found between DNA contents of M.nivale and F. sporotrichioides fungi. Any significant relations between the most abundantly present fungi of Alternaria and the parameters of grain contamination by other analyzed fungi have not been revealed. Diversity of the reactions of wheat genotypes to the invasion of various heterotrophic fungi and the possibility of using objective quantitative assessment of resistance were shown.

Background. Involving alien genetic material Hordeum bulbosum in the genome for the expansion of the genetic diversity of barley is a cultural important task because this species is characterized by a number of valuable traits. One way of using the genetic potential of bulbous barley is interspecies hybridization and the production of fertile introgressive lines of H. vulgare on the base of interspecies hybrids. The purpose of our investigation was to study introgressive lines of cultural barley obtained on the basis of the triploid hybrid H.vulgare cv 'Igri' (2x) × H. bulbosum (4x) in compare to the original Igri variety in the field conditions.

Materials and methods. In the field conditions the barley lines with intro-gressions of the genetic material of bulbous barley in the different arms of chromosomes H. vulgare (1HL, 2HL, 3HL, 5HL, 7HL, 2HS, 1HL + 5HL) were studied. Methods. In situ hybridization (FISH, GISH) was used to identify the introgressions and to analyze their saving in line karyotypes after field reproduction. For cultivated in field conditions plants the estimation of winter survival and graininess were estimated. Structural analysis of plants was carried out on tillers of the main spike after maturation. The quality of the grain was determined by the non-destructive method of monitoring - near infrared spectroscopy, using the Infralum FT-10 BIC analyzer.

Results. Closed flowering and self-pollination were observed for plants of the studied lines same as for parent variety. The introgressions were saved in the offspring when the plants cultivated in a field conditions without isolation of spike. The analysis showed that small fragments of chromosomes of H. bulbosum in chromosomes 1HL, 2HL, 3HL, 5HL,7HL, 1HL + 5HL of the studied lines do not significantly affect on characteristics (of fertility, productivity and grain quality) of the variety. Differences from the initial variety were observed at line 14.10 with the introgression of genetic material in the chromosome 2HS. It is characterized by lower fertility and productivity, and protein content in the grain is higher than that of the original variety.

Conclusions. The studied lines are highfertile forms of barley. The introgression of the genetic material of H. bulbosum into the terminal region of the short arm of the chromosome 2H causes changes in some characteristics of the Igri variety.

The creation of highly scab-resistant apple genotypes increases the profitability and environmental friendliness of the production of this fruit crop. Early stage evaluation of the resistance using phytopathological testing and DNA markers allows to accelerate the process of breeding for this trait allows the use. The purpose of the study was to comprehensively assess resistance to the causative agent of scab of hybrid seedlings of apple obtained from crossing susceptible (Rennet Simirenko) and resistant (Modi) cultivars for the Rvi6 gene, using infectious background and marker assisted selection. A phytopathological analysis of 207 hybrid apple seedlings against the natural background of apple scab pathogen revealed 117 (56%) plants without scab lesions (0 points). The remaining seedlings had lesions of varying degrees. DNA marker analysis of the Rvi6 gene allowed identification of 105 plants (51%) with the Rvi6rvi6 genotype and 102 (49%) – rvi6rvi6, which is close to a theoretical segregation ratio 1:1 in the crosses of this type. Comparison of the results of infectious evaluation and DNA-marker analysis showed 98% coincidence of the presence of the resistance gene with no lesions. In general, the complex use of the phenotypic and molecular markers evaluation of the hybrid family for resistance to Venturia inaequalis (Cooke) G. Winter shows a high degree of agreement between the results of the methods. However, the discrepancy between the qualitative classes of reactions to infection and the results of molecular genetic analysis indicates an insufficient strength of the natural infectious background of the study year. The low efficiency of the development of the disease was due to the unfavorable weather and climatic conditions at the beginning of the vegetative period and the formation of infection, which were expressed in a higher average monthly temperature and a small amount of precipitation compared to the norm. Our results suggest an advantage, a comprehensive assessment of resistance to the scab pathogen using an infectious background and marker-assisted selection for the Vf gene (Rvi6) in which the first stage involves the selection of resistant samples against a natural infectious background, followed by confirmation of the presence of the desired gene using a DNA marker analysis.

Metabolic engineering of plant secondary metabolism provides a way to obtain plants with elevated level of valuable molecular compounds. Alternatively, metabolic engineering can be used for reduction of toxic substances accumulation in plant tissues. This approach allows one to expand the application of toxic plants in agriculture and biotechnology. The crops of Solanaceae family provide an example of toxic plants of high economic value. Solanaceae family includes edible crops such as potato, tomato and eggplants, medicinal plants like Withania somnifera L. and major non-food crop Nicotiana tabacum L. The secondary metabolism of Solanaceae family is widely diverse and includes the biosynthesis and accumulation of number of toxic compounds, such as nicotine and other alkaloids in tobacco, steroidal glycoalcaloids in potato and withanolides in winter cherry W. somnifera. The secondary metabolic pathways of Solanaceae family have evolved from primary metabolism via duplication of the enzyme coding genes and diversification of genes functions. Local, segment and the whole genome duplications and subsequent formation of metabolic genes clusters are the main processes in secondary metabolic pathways formation. Recent whole genome sequence data from number of Sonanaceae species allows one to reconstruct the putative mechanism of primary and secondary metabolism genetic control and evolution. Genomic data together with novel guided endonuclease based genome modification tools provide an opportunity for introduction of precise changes into secondary metabolism. Suppression of nicotine accumulation in tobacco is promising approach for developing of novel plant systems for molecular farming. Toxicity of wild potato relatives impedes their usage in potato breeding. Tobacco and wild potato toxicity reduction can be achieved by different genome modification approaches: knock-out of the key enzyme genes of alkaloids synthesis, the large deletion of the whole cluster of the secondary metabolic genes or the precise editing of key transcription factors in secondary metabolism regulation pathways.

Background. The problem of ex situ conservation of plant genetic resources (PGR) is particularly relevant due to the decreasing of their genetic diversity. Accessions of vegetatively propagated crops are usually preserved in field genebanks. In vitro collections for medium-term storage and cryo collections for long-term storage are established as duplicate collections. Safe ex situ conservation of PGR is ensured by the existence of all three types of collections. The strategy of building up an in vitro collection of berry and fruit crops at VIR is based on the need to preserve domestic cultivars, local varieties and, primarily, landraces as well as accessions of crop wild relatives collected mainly in the Russian Federation and adjacent countries. Such genetic material is sparse or completely absent in the genebanks of other countries.

Materials and methods. Accessions from the field genebanks maintained at VIR’s experiment stations in Pavlovsk and Maikop, samples obtained by collecting teams launched by VIR and other institutions were used to initiate in vitro culture. All procedures to preserve various fruit and berry germplasm in vitro at VIR in the state of active growth and under medium-term storage conditions have been carried out according to the protocols presented in the Methodological Guidelines of VIR’s Department of Biotechnology.

Results and conclusion. Currently, the in vitro collection of berry and fruit crops at VIR holds 330 accessions of raspberry, blackberry, honeysuckle, strawberry, stone fruit plants (cherry, plum), mountain ash, and black currant, including 236 cultivars, 14 hybrids and 80 accessions of crop wild relatives, 68 of which were collected in the Russian Federation and neighboring countries. At present, VIR’s in vitro collection is one of the largest in the network of European and Asian genebanks that preserve accessions of berry and fruit plants cultivated under temperate climate conditions. Germplasm from the in vitro collection is used for various purposes: to develop virus eradication techniques; for genotyping; to study physiological and biochemical processes occurring in micro-plants under medium term storage; for the development of cryopreservation methods and for establishment of cryo collections; in morphobiological studies of ex vitro plants, etc.

This article presents a review of cryopreservation methods used to create cryocollections of plant genetic resources. The application of cryopreservation methods for the long-term conservation of the vegetatively propagated crops started relatively recently. About 60 years ago, the first methods of programmable (slow) freezing of plant objects were developed. The modern methods include such fast freezing techniques as encapsulation-dehydration, vitrification, encapsulation-vitrification, droplet-method, and droplet-vitrification. These methods are used for cryopreservation of accessions from the field genbanks and samples from in vitro collections. The review considers the main factors determining the viability and regeneration rates of explants after freezing-rewarming. The greatest impact on the efficiency of post-cryogenic explants recovery is provided by such factors as the method of the initial microplants pre-treatment, explant and cryoprotectant type, duration of the explant treatment with cryoprotectants, the composition of the nutrient medium for the post-cryogenic recovery, and the accession genotypic characteristics. The review discusses the rules for the collections formation and cryobanking development. The data on the largest cryocollections of cultivated plant species are presented.