The main directions and new achievements of the research investigations on vegetable breeding and seed production carried on the All'Russian Research Institute of vegetable breedingand seed production are shown.

Development of F1 hybrids of tomato for open ground at the moment is one of the main tasks.  It can be solved  only if there are parent forms with valuable features  and properties.  As a result of three years of research  of tomato hybrid combinations and parental lines in the open field in the non6chernozem zone; the heterosis on major economic traits has been revealed. The character  of inheritance of studied traits and the degree of dominance have been determined. The groups of hybrid combinations  with high heterosis  effect and parental lines that contribute to this effect were identified.

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.

The purpose of the study. The aim of the study was to determine the effect of heterosis in short-fruited parthenocarpic F1 cucumber hybrids by the main economically valuable characteristics, when grown using low-volume technology in industrial greenhouses of the Moscow region.Materials and methods. The object of the study is short-fruited parthenocarpic reciprocal hybrids of cucumber Druzhny (F1 I73514 x I74011), F1 I74011 x I73514 and their parent inbred lines I73514 and I74011 of selection by N.N. Timofeev Breeding Station LLC. F1 SV4097CV of foreign selection of Semenis company (Netherlands) was used as a control. The study was conducted in 2020-2021 in industrial greenhouses of the "V. I. Edelstein Vegetable Experimental Station" of the K.A. Timiryazev Russian State Agrarian University-Moscow Agricultural Academy in Moscow on low-volume hydroponics in peat bags. Parental lines and hybrid combinations were evaluated by earliness, early yield, yield, number of fruits per plant, average fruit weight and marketability.Results. According to the results of the study, F1 Druzhny (F1 I73514 x I74011) and the reverse hybrid I73514 x I74011 demonstrated high positive effects of heterosis in yield (MPH=19.4...22%; HPH=13.4...15.9%; CH=9.6...12%) and the number of fruits per plant (MPH=22.5...26.4%; HPH=12.5...15.8%; CH=11.7...15%). Negative indicators of the heterosis effect were noted for earliness from germination to flowering (MPH=-3.4...-1.1%; HPH=-6.5...-4.4%; CH=-4.4...-2.2%) and average fruit weight (MPH=-2.2...-1.3%; HPH=-5.3...-4.3%; CH=-3.4...-2.4%). The value of the degree of dominance indicates the presence of positive overdominance in the inheritance of such traits as yield (hp=2.7...3.2), the number of fruits from the plant (hp=1.5...1.9) and marketability (hp=1.6...2.3). Negative overdomination was observed in earliness from germination to flowering (hp= -2...-1.3) and average fruit weight (hp=-1.7...-1.2). According to the signs of earliness from germination to fruiting (hp =0) and early yield (hp=-0.1...0.5), intermediate inheritance was revealed. The Druzhny hybrid significantly exceeded the control hybrid SV4097CV in early yield, yield and number of fruits from the plant, and the reverse hybrid F1 I74011 x I73514 was at the control level, which indicates the prospects of growing these hybrids in the conditions of spring-summer turnover on low-volume hydroponics.

The protected cultivation technology, through which the various inbred generations with the combination of economic valuable traits and different level of sterility can be produced, is used in order to accelerate the breeding program. However, there is a negative effect of inbreeding depression and self-incompatibility can often occur and cause the loss of valuable breeding forms. The aim of the work was to study the influence of steroidal glycosides capsicoside (SGC) on exhibition of CMS, and morphobiological parameters of 13 inbred generations that were produced from fertile plant and partly sterile plants with level of sterility 10% and 50%. The seeds were soaked for 24 hours in water solution of SGC with concentration 10-3%, and in water control. Then the seeds were dried up and sown in the greenhouse. The stecklings and roots obtained were vernalized at 3-5Co. Mother plants were grown under 18 hour photoperiod in greenhouse with supplementary lighting. Inbreeding seeds were obtained in individual cloth isolators. It was shown that for all generations the treatment with SGC improved the seed germination (4-8% more), increased the root index and its length (12-24% more), decreased betanin content (22-48% less) in comparison with control. The action of SGC on the other morphological and biochemical traits such as height of leaf rosette, leaf number, plant and root weight, head size, number of generative buds, and nitrate content was defined by the level of sterility of mother plant. The most expressed effect for all traits mentioned was seen in inbreeding generations of sterile plants with high level of sterility. After action effect of seed treatment with SGC on development of seed plants from inbreeding generations, not depending on sterility level of mother plants, showed the positive influence on plant habitus of seed mother plants, decreasing the plant height, but increasing stem number and functional parameters of microgametophyte in fertile plants. This caused the improved seed formation 1.6-2.2 times higher during inbreeding process and increased the portion of plants with high productivity. The SGC had no effect on exhibition of CMS trait. Thus, the SGC is worth using in valuable highly inbreeding forms inclined to self-sterility, in order to enlarge the genetic variation and output of divers generations. However, it should be taken into consideration that the complicated effect on the plant traits can be noticed in inbreeding generation of red beet and may have an effect on the result of selection process at the root stage.

On 24-25 of September, 2013, the International Research and Practice Conference of Cole Crops was held in the All-Russian Research Institute of Vegetable Breeding and Seed Production, in terms of which the meeting of the research and methodologycal commission and open field day have been conducted.

The main directions of basic and applied researches in plant breeding and seed production of vegetable crops are presented up to 2020. The ways of improvement of organizational effectiveness are proposed.

Based on the results of molecular-genetic analysis of pepper accessions of VNIISSOK's breeding, the parental lines were selected. The diallel crossing among them has been conducted. The F1 hybrids were developed. The hybrids vigor (heterosis) for main agronomic traits was estimated. The best pepper hybrids were selected. The potential correlation between genetic divergence determined by molecular markers and heterosis effect is speculated.

. Heterotic selection is now widely used in crop production. The superiority of heterotic hybrids over varieties in many respects has long been known. However, the widespread use of heterosis in melon growing is hampered by the high cost of seed material, due to the lack of lines with male sterility. The aim of this work was to evaluate heterotic hybrids of watermelon obtained on the basis of a line with male sterility isolated at the Bykovskaya Experimental Station.Materials and methods. The studies were carried out in 2020 and 2021. at the Bykovskaya melon breeding experimental station - a branch of the FGBNU FNTSO. The object of research is heterosis hybrids of watermelon. The heterosis hybrid of watermelon Barkhan was used as a standard. Classical breeding methods were used in the work: incubation and hybridization.Research results. The assessment of watermelon hybrids according to the main economic characteristics revealed the best combinations in comparison with the standard. According to the content of dry matter, four hybrids of watermelon stood out, the excess over the standard ranged from 0.6 to 1.9%. The indicator of the average weight of the fetus in one LIR hybrid was at the level of the standard and amounted to 6.5 kg. The remaining hybrids exceeded the Barkhan standard by 1.2-4.0 kg. The average yield of the studied hybrids ranged from 19.0 to 22.5 t/ha. The calculation of such indicators as the degree of dominance, the effects of true and hypothetical heterosis made it possible to identify three combinations with high rates.Conclusion. Thus, it was found that the yield in heterotic hybrids of watermelon is inherited according to the principle of overdominance. Inheritance of traits dry matter content and average fruit weight ranges from minus overdominance to overdominance in various combinations. According to the complex of economically valuable traits, three combinations of table watermelon were distinguished: LKn, LMr and LFT.

Relevance. Providing the country's population with a variety of vegetable products is the most important socio-economic task in the Republic of Belarus. It is necessary not only to increase the production of vegetables, but also to significantly expand their range. In connection with the trend of decline in industrial production of onions, the issue of ensuring the sowing of onions in the annual culture of seeds from domestic varieties and hybrids is relevant. Also in Belarus, the problem is the provision of garlic to the population of the country.Results. In the article summarizes the results of scientific research on the breeding and development of technologies for the cultivation of onion crops in Belarus, analyzed the main and promising areas of work. Data on the results of competitive sorting of new varieties and hybrids of onion and leek, the main technological parameters of growing garlic and leeks are given.