Relevance. The research is devoted to studying the peculiarities of the high-parent heterosis manifestation which connected with yield traits and the biochemical composition of tomato fruits.Materials and Methods. The work was carried out in 2021–2023 in open field conditions on the experimental plot of the Belarusian State Agricultural Academy (Mogilev region, Belarus). The objects of research were 30 F1 hybrids and 11 parental forms with different levels of economically valuable traits and with the specific set of genes for pathogen resistance and lycopene accumulation. The aim of the research was to create high-yield heterotic F1 tomato hybrids, adapted to open field conditions in Belarus, with a valuable biochemical composition of fruits.Results. The best hybrid combinations showed an early yield of 0.90–2.49 kg/m2, a marketable yield of 7.50–11.40 kg/m2, and a total yield of 8.22–13.12 kg/m2. High heterosis effect was established for early (88.9–291.0%), marketable (36.0–111.2%), and total (28.6–97.8%) yield in some hybrids. Significant differences in the accumulation of dry matter, carotene, and soluble carbohydrates were ascertained between the hybrids. Hybrid combinations with the highest value of true heterosis on accumulation of dry matter (18.3–21.6%), carotene (20.2–22.9%), and soluble carbohydrates (15.7–38.9%) were identified. Inheritance of early, marketable and total yield, dry matter content, carotene and soluble carbohydrates predominantly took place according to the positive overdominance, fruit weight – according to the intermediate inheritance, vitamin C content – according to the negative overdominance. Hybrids Brusnichny F1, Mansiata F1, Rada F1 were transferred to the State Inspection for Testing and Protection of Plant Varieties of the Republic of Belarus and successfully passed the testing stage in 2023.

Relevance. Innovations in modern greenhouse complexes necessitate the creation of new technological cucumber hybrids for them, an important component of which is their comprehensive assessment in production conditions.Materials and methods. In 2023, experiments were conducted in the Krymsk (Krasnodar Territory) SC “Gavrish” with 9 new parthenocarpic hybrids of cucumber F1 smooth type in 2 repetitions of 10 plants each. Hybrids were grown in a winter greenhouse under light culture conditions in winter-spring and summer-autumn rotations. The technology of growing the crop is maintained in accordance with the requirements adopted in the V light zone. The assessment of economically valuable features was carried out according to generally accepted methods.Results. The early and total yields, marketability of the grown hybrids in two crop rotations, the degree of their resistance to real powdery mildew and adaptability of cultivation in crop rotations have been established. A comparative assessment of the potential of new hybrids with the generally accepted F1 analogue of Meva in the region has been carried out.Conclusions. The new parthenocarpic smooth-fruited cucumber hybrids of GC “Gavrish” F1 Metreng, Model 4560/19, Model 166/20 can act as an import substitution.

Relevance. In the context of climate change, onion cultivation has become a challenge and innovative solutions are needed to support breeders and seed producers as well as farmers, starting with critical issues of seed quality. Seed priming successfully improves seed viability, which leads to rapid and uniform germination and emergence of onion seedlings.Results. Priming onion seeds can improve viability, especially under unfavorable conditions such as low/high temperatures, reduced water availability and salinity. It is a simple, low-cost and low-risk intervention that can be a useful technology for farmers and have a positive impact on their livelihoods by increasing the rate of seed germination, increasing the rate of plant development, reducing harvest time and increasing yields. Although this method is common for radish, tomato, carrot and cabbage seeds, this method is less popular for onions. This review provides an up-to-date picture of the scientific and technological advances that have contributed to increasing seed germination and vigor in onion plants to date. For large-scale commercial use, optimal priming methods and conditions tailored to different varieties or seed lots will require further extensive experimental work. It cannot be denied that seed priming technology is characterized by ease of operation, low cost and high practical value in industrial and market contexts. It can be foreseen that this technology will have wider prospects in agricultural production and green building. In addition, seed priming can effectively restore or enhance seed viability and ensure successful retention of germplasm resources and subsequent development, especially for onion seeds that rapidly lose viability.

Relevance. The study of the reaction of potato varieties, especially new ones, to the use of a complex of agrotechnical techniques, including foliar top dressing with water-soluble fertilizers, is an urgent task. For this purpose, 4 potato varieties of different ripeness groups (Red Scarlett, Nevsky, Golubizna, Grand) were studied in two regions of Russia using agrochemicals Agrovin Micro. Methods. The article presents experimental data on the study of biometric indicators, yield and quality of potatoes for non-root top dressing in conditions of leached chernozem and sod-podzolic sandy loam soils of the Central region of Russia. The objects of research were potato varieties of various ripeness groups. Foliar fertilization of plants with agrochemicals Agrovin Micro was carried out in the phases of germination, budding and 20 days after the last treatment in two consumption rates – 1.0 and 2.0 l / ha. Control – without processing (K) with background N90Р90К135.Results. On average, over the years of research, the best options for all varieties turned out to be options with the use of additional leaf treatment with an agrochemical at a maximum dose of 2 liters /ha. Due to three-fold foliar top dressing for the critical phases of potato plant growth, the greatest yield increases and maximum values of dry matter and starch content to the mineral background were obtained. In the conditions of the Tambov region, the increase in yield, depending on the variety, ranged from 24.2 to 59.3% or 6.0-10.5 /ha and in the conditions of the Moscow region – 3.3-28.9% or 1.2-7.1 t/ha. The most suitable for processing into fried potato products from the studied varieties turned out to be Red Scarlett and Grand. All other things being equal, the color index of crispy potatoes and fries on these varieties was higher than the Nevsky variety by 1.0-1.5 points.

Relevance. The garden strawberry (Fragaria × ananassa (Weston) Duchesne ex Rozier) is a widespread berry crop distinguished by its fast vegetative growth, early bearing age, and high yield and plasticity. Today everbearing (remontant) strawberry varieties gain in popularity due to their long fruiting period, and high yield and berry quality. Annually new foreign varieties appear on the Russian market. For this reason, it is important to study foreign garden strawberry varieties of different ecological and geographical origin and identify those of them that are adaptable to agro-climatic conditions of a given region.   The research goal was to determine the biochemical and customer qualities of the garden strawberry varieties introduced in Primorsky kray and to select varieties with economically important traits for further breeding and production.   Research methods. The research was carried out in the nursery of primary variety testing at FSBSI “FSC of Agricultural Biotechnology of the Far East named after A.K. Chaiki”. The following garden strawberry varieties of foreign breeding origin were used as the research object: Сabrillo (USA), Albion (USA), Florentina (Netherlands), Murano (Italy), and Bravura (Netherlands). The studied varieties were day-neutral and everbearing. Variety Elizaveta 2 was used as the control (Russian breeding origin; admitted to use in all regions of the Russian Federation). The following parameters were evaluated: total yield, average berry weight, maximum berry weight, berry size, the yield of marketable berries, and the content of dry matter, reduced sugars, and vitamin C. The accumulation of anthocyanins in berries was determined by a rapid assessment using a color scale. Records were made and scientific observations were conducted according to “Program and methods of variety testing of fruit, berry, and nut crops” (1999).   Results. Based on the results of the research on the economically important traits of the everbearing day-neutral strawberry varieties introduced in Primorsky kray, the following varieties were selected: Cabrillo for yield (263.3 g/plant, control – 82.8 g/plant), Murano for the yield of marketable berries (81.3 %), and Bravura (15.5 g) and Florentina (15.2 g) for berry size. The highest content of dry matter was accumulated in berries of variety Аlbion (9.87%). The highest content of reduced sugars was found in varieties Cabrillo (7.16%), Florentina (7.09 %), and Аlbion (7.09 %); of vitamin C – in Florentina (60.30 mg/100 g), and of anthocyanins – in Murano (50 mg/100 g). Murano was established to be the most promising variety under the conditions of Primorky kray for the complex of its traits.

Relevance. Nowadays the popularity of Chamaenerion angustifolium as a medicinal plant and as a tea is growing noticeably. Fireweed is an eclogically plastic species, that does not require high soil fertility and is widespread in Russia. Medical and food industries use leafs as a row material of fireweed. Series of phytochemical studies of Chamaenerion raw material have shown that it contains a wide variety of pharmacologically significant compounds, that accumulate as a result of both primary and secondary metabolism. The most important groups, formed as a result of secondary metabolism, are polyphenols, including flavonoids, phenolic acids and ellagitannins (including enothein B). Concentration of these chemical compounds equals 15% and even hither of the raw material (leaf).The aim. Identification of variability and relationships between the content of various groups of phenolic compounds in raw material of Chamaenerion angustifolium, depending on ecological conditions.Methods. At the first stage of our work was used the cartographic method. Were studied specimens from 27 points, growing in ecologically different areas of the Moscow, Kaluga and Yaroslavl regions. Phenolic compounds were determined using a spectrophotometer: flavonoids in terms of rutin, tannins and the amount of phenolic compounds, using the Folin-Ciocalteu reagent in terms of gallic acid.Results. The content of polyphenols, tannins and flavonoids in raw material of fireweed, collected in different ecological and soil aspects, was measured. Measurement results were compared, using correlation analysis. As the result of content analysis, it was found that the content of polyphenols in the leaves ranged from 9 to 11%, the content of flavonoids fell within the chain range of 2.5-3.5%, tannin content – 5.0-6.5%. A close correlation was found between the content of phenolic compounds and tannins (R=0.972). It indicates, that the shikimate pathway is the main process of biosynthesis secondary metabolites in the Chamaenerion angustifolium plant. Also it means the leading role of local ecological conditions of the studied areas.

Relevance. The selection of genotypes with high adaptive properties for the conditions of the Tyumen region allows us to contribute to the development of a regional strategy for breeding and genetic work, selection and cultivation of varieties in connection with changing weather and climatic conditions.Material and methodology. The research was carried out over a three-year period (2020-2022) in the northern forest-steppe zone of the Tyumen region. Intervarietal hybridization (4x4 scheme), evaluation of the obtained material according to morphological (4 pcs.), biological (1 pc.), adaptive indicators (2 pcs.) was carried out using generally accepted methods. The objects of study were 12 combinations of fiber flax, first obtained in the region.Results. Significant differences (p<0.05*) were determined between hybrid populations of fiber flax in the influence of genotype, environment, and genotype-environment interaction on the degree of implementation of the studied traits. Correlation relationships have been identified that determine the fiber content in the stem (r=0.79-0.91*, growing season, plant height, inflorescence length, softness, camber), the number and weight of seeds per plant (r=0.79-0 ,91*, inflorescence length, number, size and crackability of the capsule). Based on the results of individual selection in the third hybrid generation (F3), early ripening (4 pieces), tall (n=4), with the maximum number of bolls (n=4) and the number of seeds in them (n=7), fiber content (n =4) in the stem of the combination.Conclusions. Hybrid combinations of fiber flax with high levels of stable properties (G1, G3, G9, G10, G11), productivity criteria (G1, G2, G4, G7, G8, G9, G11, G12) can be valuable in breeding work.

Relevance. To improve the quality of life and expand the taste preferences of the population of Belarus, it is necessary to expand the range of vegetable crops with high yields, marketability and product quality, adapted to the natural and climatic conditions of the republic. In this regard, improving technological methods for cultivating such a crop as zucchini (Cucurbita pepo L.) is of scientific and practical importance.   Materials and Methods. The research was carried out on the territory of a private farm in the village of Chukhny, Smorgon district. Field and laboratory studies were carried out using generally accepted methods and guidelines.   Results. Substantiated the feasibility of cultivating green manure crops in combination with the local application of thermoammonia-disinfected compost when growing zucchini in seedlings on sod-podzolic light loamy soils in the natural climatic conditions of Belarus. The developed technological methods ensure the reproduction of soil fertility, increased yield, and production of high quality products without the use of mineral fertilizers. When using green manure and disinfected compost, the nitrate content in zucchini cv. Bonus, grown without mineral fertilizers, was in the range of 280-320 mg/kg. To reproduce the fertility of soddy-podzolic light loamy soils when growing zucchini in the natural climatic conditions of Belarus, it is advisable to use oats, oilseed radish and peas as green manure fertilizers. This technological technique increases the content of organic matter in the soil by 0.8-1.3 %. Together with green manure, adding thermo-ammonia-disinfected compost into a hole when planting zucchini seedlings ensures an increase in organic matter content by 1.2-1.5 % in the compost localization zone. During the decomposition of organic matter of green manure crops and disinfected compost applied locally, nutrients are released in quantities sufficient to form a high yield of zucchini with a nitrate content below the maximum permissible concentration. Thus, when grown on soddy-podzolic light loamy soils in the natural climatic conditions of Belarus, the proposed technological methods make it possible to obtain high-quality products and significantly increase the yield of zucchini due to green manure in combination with the local application of disinfected compost without the use of mineral fertilizers.

Relevance. Grain of vegetable pea varieties is processed at canning factories, frozen, dried, and consumed fresh. Industrial cultivation of peas can be made more environmentally friendly by using biological preparations that contain growth-stimulating bacteria, for example Rhizobium species. With additional inoculation with rhizobacteria, legumes have higher values of traits characterizing vegetative development, biochemical parameters and yield; their immunity and resistance to abiotic stress increases as well.Methodology. The aim of our study was to evaluate the effect of additional inoculation of Rhizobium leguminosarum strain 245a on biometric and physiological parameters and yield of vegetable pea varieties. The experiment was carried out at Krymsk Experiment Breeding Station – a branch of VIR (Krasnodar Region, Krymsk). We studied six commercial cultivar: Prima, Mayak, Alpha 2, Vesta, Parus (leafless morphotype) and Patriot. The seeds were treated the day before sowing with an aqueous solution of the biopreparation Rhizotorfin (produced by ECOS BIOPREPARATIONS, St.Petersburg) and with water in the control variant.Results. The use of the preparation had a growth-stimulating effect on vegetable pea plants. An increase in the length of plants, the height of attachment of the lower pod and the number of completed pods on the plant was found. An increase in the content of dry matter in the total biomass of plants, stems with leaves and pods was noted when using Rhizotorfin. Also, inoculation with rhizobacteria contributed to an increase in yield. The effectiveness of the biopreparation depended on the conditions of the year. The maximum difference between the values of the studied traits for the control and treatment variants was in 2023 - with a uniform distribution of precipitation and optimal temperatures during the growing season. A genotype-dependent reaction of vegetable pea plants to seed treatment with bacteria Rhizobium leguminosarum strain 245a was revealed. The most responsive to additional inoculation is the variety Parus of the leafless morphotype. The values of most biometric and physiological traits and yield in this genotype were significantly higher in the variant with the use of the Rhizotorfin biopreparation. Based on the results obtained, we recommend using the Rhizotorfin biopreparation when growing the variety Parus for commercial production.

Relevance. The technology of producing cabbage seeds with the traditional method takes almost 2 years. Its high labor intensity caused the need to search for cheaper methods of selection and seed production. One of the ways to speed up the stages of the selection process is the use of artificial climate chambers. The aim of research is to obtain seeds of promising inbred lines of late maturing white cabbage and hybrid combinations with their participation using rosette plants (steckling) in artificial climate chambers. Materials and Methods. The material was inbred pure lines of 5-6 generations of inbreeding, obtained from promising hybrid combinations of domestic and foreign breeding. The research was conducted in 2023-2024. Sowing in Plantek 64 cassettes was carried out on July 10, then the seedlings were transplanted into vegetative vessels with an optimal volume of 5-6 liters and installed in the open ground for the growth of a leaf outlet. In the phase 10-13 of real leaves, the plugs were placed in an artificial climate chamber. During the growth and development period, biometric and phenological observations were carried out, and an analysis of seed setting was carried out during the hybridization of inbred lines.Results. As a result of research in the study of hybrid seed production under artificial climate chamber conditions, high rates of seed setting in buds under cross-pollination of rosette plants of white cabbage were revealed. Genotypes with high seed set rate under geitenogamous bud pollination were also identified. The weight of 1000 seeds of the studied plants was within the range of 2.5-5.14 g. Genotypes 383-3, 384-2 and 384-7 were selected, which had the highest percentage of seeds in the fractional composition with size more than 2 mm 80.3%, 43.5% and 59.4%, respectively. When genotypes 384-2 and 384-7 were used in hybrid combinations as a maternal component, high quality indicators of the obtained seeds were revealed.Conclusion. For the studied genotypes of white cabbage, when grown in an artificial climate chamber, no significant effect on seed quality was found; the genotype had a greater effect on seed quality indicators.