Relevance. One of the conditions for creating a modern high-tech hybrid of sweet pepper is the presence of resistance to the Pepper mild mottle virus (PMMoV). This virus belongs to the genus Tobamovirus. This virus can spread through seeds, causing enormous damage to the sweet pepper crop. The main method of controlling of virus is the cultivation of F1 hybrids of pepper with genetic resistance. To date, the L4 gene is able to confer resistance to all known strains of this virus. However, there is still no reliable marker system that could be integrated into the MAS. Methods. Based on data from the NCBI, we generated a molecular diagnostic system based on hybridization probes. Validation was performed on seven pepper accessions from the world's germplasm banks. After validation, the new marker was successfully tested on 2540 plants of F2 and F3 generation. Results. Using the experimental marker system Fret4, we tested 7 reference samples of pepper germplasm with full correspondence of the melt peaks to the declared alleles of the L gene (L0/L1/L3/L4). Then, using a marker system, MAS was carried out on 10 populations of an number of 10 thousand plants to identify the L4 allele. As a result, we were able to create a highly accurate and cost-effective marker system for the most important pepper resistance gene. This marker system based on hybridization probes is easily integrated into the MAS, allowing fast and reliable determination of the L4 allele state in sweet pepper breeding to Tobamovirus.

Relevance and methods. Pumpkin fruits and seeds are valuable raw materials for the food and pharmaceutical industries. Of particular value are pumpkin seeds, from which oil and protein products are obtained. The purpose of our research is to identify the best breeding samples of pumpkin in terms of seed yield and pumpkin oil and to study their biochemical composition. The evaluation of 12 samples of pumpkin was carried out according to the main economic and biological characteristics. Results. According to the yield of seeds and the yield of pumpkin oil, the following samples were distinguished: Delta, Golosemyanno-kustovaya, Line 2-3, Line 2-5. The biochemical composition of seed samples with high seed yields was studied in terms of the content of proteins, fats, carbohydrates, amino acids, fatty acids, vitamins and minerals. A biochemical analysis of pumpkin seed oil for fatty acids, sterols and minerals was carried out. Seeds of hard-barked pumpkin of Belarusian selection are sources of high protein content (34-35%) with a wide range of essential amino acids, fats (43-45.8%), unsaturated and saturated fatty acids, as well as carbohydrates (9.6-11.9%) , a number of vitamins, macro- and microelements.

Relevance and methods. he article examines the impact of phytosanitary standards on international trade in plant products. It is noted that it is complex in two ways: on the one hand, phytosanitary control protects against low-quality goods, non-native pests and diseases, on the other – negatively affects international trade, makes it difficult for small producers to enter the market, especially when it comes to developing countries. The study provides examples of Vietnam and Chile. Results. It is concluded that excessively strict phytosanitary regulations act more as a barrier than as a catalyst for trade. Moreover, there is a tendency to tighten requirements. The authors draw attention not only to the necessity, but also to the complexity of harmonization of phytosanitary standards.

Relevance. A study of the seasonal (phenological) phenomena and natural connections between them on the background of the relevant environmental conditions is of great scientific and practical interest. Knowledge of the dynamics of the seasonal development of woody plants helps in the selection of species and their assessment from an aesthetic and sanitary points of view, as well as in the development and implementation of measures to increase the sustainability of urban green spaces. Materials and methods. The purpose of these studies is to create a database of the dynamics of seasonal development of North American woody plants based on the results of many years of phenological monitoring (2003-2017). The 20 species and forms of North American woody introducers e of the VNIISPK arboretum genetic collection were the objects. Results. It was revealed that the growing season of woody North American plants corresponds to the climatic conditions of the forest-steppe zone of central Russia. The species with the earliest beginning of the growing season (the third decade of March) were distinguished. There were Mahonia pinnata, M. aquifolia, Betula lenta and B. lutea. On the basis of phenological calendars, phenological spectrums have been constructed. These consist of three lines (the development of leaves, shoots, flowers and fruits) with the corresponding color symbols. It has been revealed that phenospectrums vary depending on the conditions of the year. As a result, the database of 20 species and forms of North American woody plants was formed in the form of phenological spectrums against the background of registration of weather conditions in the forest-steppe zone of Russia. The database includes three options for the possible dynamics of the seasonal development of introduced North American plants. The created database allows observing, comparing, evaluating and forecasting changes in the seasonal rhythm of the studied species of introduced North American plants.

Relevance and methods. For the Non-chernozem zone, the main factor for the active development of late blight is the low air temperature and its sharp fluctuations during the day, contributing to the formation of increased air humidity and drip-liquid moisture on the plants. In the Moscow region, the causative agent of late blight is manifested almost annually. Populations of Phytophthora infestans are represented by the To and T1 races. Epiphytotic development was observed periodically (1977-1979, 1982, 1986, 1996-1999, 2000, 2001, 2003-2004, 2008-2009, 2013, 2014, 2015, 2016, 2017, 2019) and was provided by the virulent T1 race. Observations showed that epiphytotic situations arose in those years when the minimum air temperature was below long-term average values, and relative humidity and precipitation exceeded them. With a deviation from the norm in the direction of increasing temperature, decreasing rainfall and relatively low humidity, years were observed with a depressive (1992, 1994) or moderate development of the disease (1980, 1981, 1983, 1985, 1987-1991, 2002, 2005-2007, 2010-2012, 2018). Results. As a result of breeding work, a Grot tomato-tolerant tomato variety was obtained, on the basis of which varieties with high resistance Grand, Dubok, Gnom, Chelnok, Patris, Geya, Zolushka, Perst, Severyanka, Blagodatny were obtained. In the general collection of VIR as a source resistance to leaf spot pathogens were registered: Geya (v.k. 14839), Slavyanka (v.k. 14840), Patrice (v.k. 14841), Rossiyanka (v.k. 14842), Krepysh (v.k. 14843), Sibiryachka (v.k. 14444) and line 1079-94 (v.k. 14845) donors, in addition to their high resistance to late blight, have excellent economic characteristics.

Relevance. New types of vegetable crops, previously unknown on a large scale, appear on the market. Japanese cabbage (Brassica rapa L. subsp. nipposinica (L. H. Bailey) Hanelt) is one of such crops for the middle zone of the Russian Federation. Due to the high content of vitamin C and microelements, Japanese cabbage can be classified as a rational balanced diet, including dietary one, and it can also be used as a raw material for the medical industry. Methods. The study of a promising sample of Japanese cabbage selection at the Federal Research Vegetable Center consisted in phenological observation of the stages of plant growth and development, morphological study of economically valuable traits, and biochemical analyzes of the content of ascorbic acid, dry matter and photosynthetic pigments. Results. The results of observations made it possible to establish the timing of the onset of phenological phases in Japanese cabbage plants and showed that the active formation of leaf mass in plants occurs 20 days after planting the seedlings. A close direct relationship was established between the duration of economic shelf life and the number of leaves in a plant (R = 0.95) and the length of the leaf plate (R=0.92). In the conducted biochemical studies, it was revealed that the content of ascorbic acid in the promising sample is 37.84±0.88 mg%, and the dry matter is in the range of 11.3±0.42%. The content of antioxidants in terms of HA and AA is within 5.72±0.72 and 19.5±2.46 mg/g, respectively. The study of the morphological characteristics and biological characteristics of Japanese cabbage plants contribute to the maximum use of the potential of vegetable crops in the conditions of the Moscow region.

Deoxyribonucleic acid (DNA) is one of the main carriers of hereditary information. The structural physicochemical information of DNA ultimately determines the structure and functioning of all living organisms. In DNA, various mutational events accumulate and recombination events occur, which lead to the variability of organisms and are subject to both natural and artificial selection. The interaction "genotype-environment" inherent in all living organisms is also characteristic of DNA, which is located in the intracellular and intranuclear physicochemical environment of water molecules, sugars, metal ions, pH, nucleotides and other components. The establishment and study of the physicochemical properties of native DNA contributes to not only understanding the mechanisms of the structure of the main hereditary biomolecule, but also to clarify their functioning, as well as interaction with other molecules at the molecular level. The discovery of various forms of double helices: A, Aʹ, B, α-Bʹ, β-Bʹ, C, Cʹ, Cʹʹ, D, E and Z suggests the idea of molecular genetic diversity existing at the DNA level and the establishment of their structural and functional features can lead to an understanding of the implementation of genetic information at the general biological level. The structure of natural DNA as a whole, apparently, does not depend on the sequence and nucleotide composition. For natural molecules - satellite DNA with repeats or DNA without repeats, the presence of only A-, B- and C-forms has been confirmed. The structure of DNA depends not only on temperature, but also on the nature of the cations present. The presence of a certain amount of metal ions in the medium can lead to the transition of the B-form of DNA to the Zform. The B ↔ Z transition modifies the general structure of DNA and, therefore, may be important for the regulation of gene expression. The study of the biological role of Z-DNA, possibly in the near future, will help to understand the mechanism of gene expression, primarily of an epigenetic nature, which has not yet been fully elucidated.

Relevance. The non-chernozem zone of Russia and the more northern regions of the country are far from the most favorable zones for the cultivation of tomatoes in open ground. The most promising for the northern zones of Russia are earlyripening, cold-resistant varieties and hybrids of tomato. The most promising in terms of productivity, resistance to short-term frosts and late blight damage are standard and semi-standard forms of tomato. Stamp forms (var. validum Brezh.) are of significant interest, both for breeding, genetic studies of tomato culture, and for production.Results. In the laboratory of selection and seed production of solanaceous crops of the FSBSI FSVC (VNIISSOK) in recent years, a whole series of standard early ripe tomato varieties for open ground has been created (Chelnok, Revansh, Pervotsvet, Argo, Evgeniya, Malinka, Otradny). The involvement of the selected standard forms in the crosses made it possible to create a number of promising lines and varieties of the semi-standard form (Perst, Pervotsvet, Blagodatny, Dolgonosik, Voskhod VNIISSOK), which significantly increases the genetic diversity of the standard forms. These varieties with a solids content of up to 7.5%, with a long shelf life. In the non-chernozem zone and the more northern regions of the country, the VNIISSOK selection varieties easily tolerate a short-term decrease in day and night temperatures to 0…-1°C, and in the southern regions drought.

Relevance. Broccoli cabbage (Brassica oleracea L. convar. botrytis (L.) Alef. var. cymosa Duch.) is widely spread around the world due to its dietetic attribute, preventive and healing effect, cooking simplicity. F1 hybrids production is the main stream in modern crop breeding as they surpass varieties in evenness and yield quality. However, it takes up to 6 years of inbreeding to obtain pure parent lines capable for hybrid creation. Thus biotechnological methods, especially doubled haploids production technology shell be implemented in selection process. 100% homozygous line can be worked out in one generation by this technology. Nevertheless earlier researches revealed such plants low seed set that hinder their application in mass production. Therefore after pollination seed set level identification is an important step in applying lines gained via in vitro process.Materials and methods. Broccoli cabbage regenerated plants produced by isolated microspore in vitro culture method were used as raw material in our study. Flower and bud pollination was held in climate cells.Results. Study of 11 broccoli cabbage DH-lines disclosed genotype influence the ability to set seeds after bud pollination. 93.3% genotype A and 95.5% A1.3 pods were seedless in our experiments. Most genotypes demonstrated 50.3-85.7% seed set level. Low and middle ability to form seeds prevailed mainly. This peculiarity should be considered while dealing with regenerated plants by raising the number of crossings for successful breeding.

Relevance. The structure of the food market is represented by various types of products, of which the largest share is taken by the fruit and vegetable sector. In the conditions of a tense political situation in the world and the establishment of barriers in foreign trade, agriculture is a strategically important branch of the Russian economy. Today, the fruit and vegetable sector of the Russian economy does not fully satisfy the needs of the population for vegetables and fruits. This is evidenced by the fact that the domestic market does not provide the population with high-quality vegetables and fruits, creates favorable conditions for filling it with foreign goods, which constitute about 35% of the consumer basket of Russians. All this leads to the need for additional analysis to identify trends in the development of the Russian market for fruits and vegetables and to identify priority areas for its development.Methods. The purpose of the article is to conduct an analysis of the main trends in the development of the Russian fruit and vegetable market, in order to determine the priority areas of its operation. The basis of the study was the statistical data of the customs authorities of the Russian Federation on the import and export of fruits and vegetables, as well as the federal service of state statistics on the volumes of production and consumption of fruits and vegetables in Russia.Results. As a result of the analysis of the state of the fruit and vegetable market in Russia in 2011-2018, carried out in the article. It can be stated that the population is experiencing a shortage of consumption of fruits and vegetables. Over the past eight years, imports exceeded exports in the structure of commodity circulation of fruits and vegetables, which indicates the dependence of the national market on foreign goods. The state of the fruit and vegetable market is influenced by the following factors: the level of development of the logistics infrastructure, material and technical equipment of enterprises, as well as the presence of sanctions and counter sanctions.