Relevance. Lettuce is a widespread green crop. The high demand for lettuce products, as well as for new varieties, drives the development of different breeding practices for this crop. It is the most promising to use hybridization method in the lettuce breeding for a diverse source material production. However, lettuce is a self-pollinating plant with small flowers and a short flowering period (about three hours), so the technique of castration and pollination is difficult. The current methods of lettuce hybridization vary in efficiency and labor intensity. This study aims to compare the effectiveness of three different hybridization methods and to obtain a source material for lettuce breeding using these methods.

Materials and methods. 15 varieties of different variety types of lettuce were studied in various combinations. Three hybridization methods was conducted in the conditions of the Moscow region and the Krasnodar Territory: 1) using flies as pollinating insects, 2) using manual castration by cutting off the inflorescence of unopened buds with pollen inside and washing off pollen residues followed by manual pollination ("Clip and Wash" method), and 3) using manual emas- culation with a single pollen wash, also followed by manual pollination. The hybridity level assessment and the breeding material selection were performed according to the main morpho- logical and economically valuable characteristics.

Results. In the period from 2021 to 2023, 529 hybrid plants were produced using three different hybridization methods of lettuce. Out of these, 150 plants of various variety types and forms were selected for further breeding. The "Clip and Wash" method was found to be the most effective in terms of achieving the highest hybridization percentage (92-100%) with less labor costs in organizing crosses. However, the hybridization process using insect pollination was less effective and required more labor, but it was also possible to pollinate a larger number of inflorescences using this method.

Relevance. Tomato late blight caused by Phytophthora infestans can cause almost 100% yield loss in open ground in cool and humid conditions. At the same time, the genetic characteristics of P. infestans allow it to overcome the genetic resistance of host plants over time, which requires breeders to look for new genes for resistance to late blight and to obtain new varieties that have several resistance genes at once.
Material and methods. 12 tomato lines, or a total of 335 plants, were obtained from the N.N. Timofeev breeding station collection and planted in an artificially infected background. For molecular genetic screening, 12 plants from the Kr6 line were used. The markers linked to the late blight resistance genes Ph-3, R1, and R3a were utilized.
Results. On an artificial infectious background, phenotypic evaluation of tomato resistance to late blight showed 1 line of plants free of pathogen damage, 5 lines of plants fully afflicted by late blight, and 6 lines with only partial plant damage. According to molecular genetic investigation the resistant plants were heterozygotes for the Ph-3 gene. Furthermore, the R1 gene was present in most of the plants under study; but, without the Ph-3 gene, this gene did not provide plant resistance against late blight.
Conclusions. The results of this research led to the selection of tomato plants for further breeding that were resistant to late blight. It was shown that markers linked to the Ph-3 and R1 genes might be used for marker-mediated selection. Furthermore, it has been established that tomato plants are more effectively protected against P. infestans when several resistance genes are present.

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. 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.

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. To meet the demand of the domestic consumer and the effective import substitution of for- eign breeding varieties, Garden phlox (Phlox paniculata L.) needs to breed new varieties with high decorative properties, stability and unpretentiousness. A prerequisite for successful generative reproduction of flowering plants to obtain new forms and varieties is the production of fertile, morphologically complete pollen.
Methodology. The purpose of this work is to study the biological features of garden phlox flowering and pollination as part of the breeding process optimization and selecting promising parent pairs. The research was carried out for 2 years (2022-2023) in open ground conditions on the basis of the garden phlox domestic varieties bioresource collection on the territory of the Tsitsin’s Main Botanical Garden of the Russian Academy of Sciences. The peculiarities of the varieties flowering and pollination biology, by assessing the viability of pollen, were studied during the mass flowering phase in 11 varieties selected for their prospects for breeding using methods for assessing pollen viability by staining pollen with acetocarmine and using the M. Alexander method.
Results. During the research, a number of garden phlox economically valuable features were established: variability structure of the inflorescence and flower morphology; duration of flowering (35 days or more); different periods of flowering (from mid-June to the end of August); the ability of some varieties to bloom again. It was found that the Alexander’s pollen staining method is more sensitive than acetocarmine staining, and allows for more accurate differentiation of colored pollen grains according to their fertility degree. For artificial pollination and hybridization in phlox, it is recommended to use fresh pollen collected from blooming and fading flowers, since it is in these phases that the pollen fertility index in some varieties exceeded 50% of the total weight. According to the results of the conducted research, the most promising pollinator varieties with a high level of pollen fertility were identified: Skazka (71.2%), Olenka (63.2%) and Gegery (66.7%). The prospect of using the Manon variety as a source of male sterility has been established. 

Relevance. This article presents the results of breeding work and the introduction of the Mesoamerican culture Spanish sage or chia (Salvia hispanica L.), which is currently one of the most popular pseudo-grain crops from the family of Lamiaceae in Western countries due to its unique seeds rich in nutrients, PUFA, dietary fiber and antioxidants. In 2009, the European Union considered the seeds of the plant to be a promising type of food. There are only 17 registered genotypes of culture in the world, in the collection of GRR VIR there are two forms obtained from European countries. There are no registered varieties of Spanish sage in the state register of breeding achievements approved for use in the territory of the Russian Federation. The research of this culture is limited only by the biological side: the study of morphobiological features, its use for decorative purposes.
Material and methodology. The research was conducted in the educational and experimental farm of the Omsk State Agrarian University in 2019-2023. The objects of research were several samples of various ecological and geographical origin and 2 new forms of Spanish sage obtained during local selection. All records and observations were carried out according to the following methods: field experience in vegetable growing (S.S. Litvinov, 2011), State variety testing of agricultural crops (1989), assessment of primary introduction by G.P. Semenova (2001) and variety assessment of floral ornamental plants by V.N. Bylov (1971).
Results. As a result of continuous year-round introduction work, the breeders of the Omsk State Agricultural University managed to overcome the photoperiodic sensitivity of the plant and obtain adaptive forms 0/18 and 3/18. An assessment of the decorative value, the success of the introduction and the possibility of introducing new samples into production in the conditions of the southern forest-steppe of Western Siberia is given. The first of the locally obtained forms, as more productive, was transferred to the state variety testing in 2023 under the assumed name of the variety "Siberian Emerald". Breeding work in this direction continues.

Relevance. During the formation of cabbage heads, under certain conditions, white cabbage is damaged by a burn of the top of the inner leaves of the head, which abroad received the stable name “tip burn”. This disorder is interpreted as a physiological or non-infectious disease, the cause of which is a violation of calcium intake. The disease manifests itself inside the cabbage head, resulting from the interaction of environmental stress factors and the predisposed genotype. The most effective way to combat this disorder is to develop highly tolerant hybrids. This is especially true for the south of Russia, where the stress load on plants is maximum.
Purpose of the study – to develop a principle for selecting parental pairs for developing hybrids that are resistant to the tip burn of the inner leaves of a cabbage head, and to identify promising hybrids. Materials and methods. In 2021-2022 in FSBSI "Federal Scientific Rice Centre", in the department of vegetable growing, 45 hybrid combinations obtained on the basis of 10 inbred lines were assessed under field conditions for the trait "burn damage to the inner leaves of the cabbage head." An analysis of the combining ability of lines according to Griffin, and an analysis of the inheritance of the trait according to Heiman were carried out. In 2023, a competitive test of promising hybrids was carried out.
Results. In both years of research, 5 lines had negatively stable TCA for burn damage: Ten4270, Yas25p, Bs1f, Agr 82, 270Hn111. SCA of lines is more subject to changes from year to year. The effects of SCA in hybrids due to dominance, epistasis and overdominance in individual combinations significantly influence the manifestation of the trait in the direction of decrease or increase. The principle of selecting parental pairs to develop stable hybrids is based on a combination of lines with a negative SCA value; in some cases, it is permissible to include one line with an average SCA and low SCA. Analysis of genetic parameters according to Heiman confirms the prevalence of non-additive inheritance of the lesion; in unstable forms, the disorder is controlled by dominant polygenes and is highly heritable.

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. Opuntia distinguished by high adaptability is widespread in many countries of the world. Tolerance to water deficiency and high biological activity provide prospects of its cultivation for food and pharmaceutical industry. In Russia Opuntia is grown in the Crimea, Caucasus, Donbass, Astrakhan region and even in the Central Russia. Evaluation of the Opuntia cultivation efficiency in the Crimea for various utilization supposes the importance of its biochemical characteristics which variability greatly depends on the place of habitat. 
Materials and Methods. Total antioxidant activity and titratable acidity were determined using titration methods, polyphenol content –using spectrophotometric method, monosaccharide and total sugar concentrations were assessed via reaction with ferricyanide, mucilage levels were determined gravimetrically.
Results. Investigation of cladode, inflorescence and fruit biochemical parameters of three Opuntia species: O. humifusa, O. phaeacantha, O. engelmannii, – gathered at the Southern and South-Eastern part of the Crimean peninsular revealed wide variability of fruit mucilage (4.3-16.56% d.w.), sugar and total antioxidant activity. Polyphenol content decreased according to: inflorescence (18.4-21.0) > fruit (11.7-18) > cladodes (10.2-20.0). Fruit monosaccharide content reached (6.2-31) % while in cladodes these values were in the range of 8.1-16.0%. Total sugar content was equal to 32.6-95% in fruit and 15.5-29.7% in cladodes. Concentration of selenium as a natural antioxidant was higher in the cladodes (102-176 µg/kg d.w.) than in fruit (46.8-72 µg/kg d.w.). The highest levels of the total antioxidant activity and titratable acidity were registered in O. engelmannii while the highest sugar, mucilage and taste index were typical for O. humifusa. Nevertheless, O. humifusa was characterized by the lowest fruit mass (6.0-6.3 g) contrary to O. engelmannii (36-40 g). The results suppose prospects of fruit, cladode and inflorescence utilization in food industry, cosmetics and pharmacology with the preference to O. humifusa.

Relevance. The use of mineral fertilizers in the cultivation of tomato in the first place should ensure the best conditions for the nutrition of plants during the entire growing season in accordance with their need.
The research methodology was based on generally accepted methods for vegetable growing. The main goal of this study was to improve the zonal technology for cultivating tomato in open ground using leaf dressing with KCL and KNO3 preparations, aimed at increasing the level of yield during irrigation in the north of the Astrakhan region. Field experiments were carried out at the experimental irrigated land use area of the Federal State Budgetary Scientific Institution "Caspian Agrarian Federal Scientific Center of the Russian Academy of Sciences" in the period from 2021 to 2023. The scientific novelty of the study was the theoretical and practical justification for the use of leaf dressing with KCL and KNO3 in the cultivation of vegetables, aimed at the formation of highly productive commercial products.
Results. During the research work, a comparative analysis of various standards of use of drugs was carried out, highlighting the most promising option. Three-year studies found that the use of potassium fertilizer KCl with a concentration of 0.5%), 30... 40 days. after planting (flowering), 50 days. after planting and 60 days. after planting gave a significant increase in yield relative to the control option. Conclusions. Based on the results of the analysis, an average of five charges, the KCl treatment variant Background + 3 (concentration 0.5%) was identified, which had the highest yield of 130.56 t/ha. This option was significantly different from both control and other options under study. The increase relative to the control was + 4.08 t/ha or + 3.2%.

Relevance. The increase in global production of garden strawberry fruit is due to the high demand for the products for fresh consumption and as raw material for processing. The leading countries are: PRC, USA, Turkey, Egypt, Mexico, Spain, Russia, Poland, South Korea, Brazil. Increase in production volumes is provided due to high productivity of new varieties and intensification of strawberry cultivation technologies and, in particular, plant nutrition. The possibility of managing the nutrition of garden strawberry plants is one of the priority tasks from the solution of which depends on the realization of the potential of plant productivity, as well as the quality of the resulting products The role of many macroand microelements in plant nutrition is not fully understood. Numerous studies are conducted to identify the mechanisms of their absorption and movement in strawberry plants. New forms of fertilizers are being studied, allowing to effectively influence the processes of growth and development of plants, minimize the impact on the environment.
Results. The article is devoted to the review of the role of the main mineral macroand microelements in plant nutrition, such as nitrogen, phosphorus, potassium, magnesium, calcium, iron, silicon, molybdenum. Based on the analysis of literary sources, the influence of certain mineral elements on physiological processes associated with the growth and development of garden strawberries is considered. The data on reaction of plants to the optimal content, excess and deficiency of certain elements, possibilities of their receipt and assimilation by plants of garden strawberries are given. Application in practice of the world experience on management of mineral nutrition can significantly improve the existing technologies of strawberry cultivation in open and protected ground.

Relevance. Trophic relationships along with competition and mutualism are the most basic and significant interactions in ecosystems. To develop, survive, and multiply, insects need to consume a certain amount of nutrients at a certain ratio. Food products are complex mixes of nutrients and non-nutritive substances (sometimes toxic ones): macronutrients (proteins, carbohydrates, and lipids), micronutrients (vitamins and minerals), and water. Some nutrients are essential; insects lack the ability to synthesize them in their bodies and must obtain them from their diet or through symbiosis with beneficial organisms. Identification mechanisms being well developed in the system “phytophagous insect – plant” allow insects to successfully spread, multiply, and feed on certain plant species. The complex of hydrolytic enzymes in the insect intestine is one of the main targets for plant defense responses because these enzymes determine the availability of structural compounds for phytophagous insects. For this reason, enzymes in the insect intestine play a key role in the adaptation of insects to the pest resistance of fodder plants. For instance, when proteinase inhibitors are synthesized in a fodder plant as the result of induced insect resistance the complex of enzymes in an insect intestine might change negating the effect of these inhibitors. The development of co-adaptations due to interactions among species in food chains depends on a complicated constellation of conflicting relationships between consumers and food objects. The mechanisms of this influence may be rooted in the allelochemical interactions in the system “phytophagous insect – plant recipient”. Allelopathic interactions are among the most complex interactions because they are constituted by direct and indirect effects. Plants when damaged by phytophagous insects activate defense responses, which incorporate several mechanisms, including an increase in the concentration of secondary metabolites, many of which are phenolic compounds.
The aim of the work is to describe the mechanisms of relationships in the system “phytophage-plant”. Conclusion. Management of processes of intra-water divergence of insect-phytophages in agrobiocoenoses in order to prevent the emergence of races and populations of pests adapted to live on initially resistant to them plant forms is possible in compliance with the transition to a targeted selection of agricultural crops for resistance to a complex of pests.

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.