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. In the transition to highly productive and environmentally friendly, in particular, organic agriculture and production of safe and high-quality products, which is a priority direction of strategies of scientific and technological development of the Russian Federation, one of the necessary links is the creation and control of optimal conditions of plant nutrition, i.e. provision of plants with nutrients in the right combination throughout the vegetation. Achievement of such conditions is possible through soil and plant nutrition diagnostics, which in turn allows to establish the ability of crops to assimilate nutrients from the soil and adjust the doses of mineral fertilisers as top dressings.Material and Methods. On alluvial meadow soil in the conditions of the non-Black Earth region of Russia, the effectiveness of root feeding with macronutrients (NPK) was studied according to the results of plant and soil diagnostics of table root crops nutrition when grown on organic and mineral fertiliser systems. Plant and soil diagnostics of mineral nutrition was carried out according to the methods of Zerling V.V. (1990) and Magnitsky K.P. (1972). Two crops were tested during the experiment: red beet variety Mulatka and garden carrot variety Losinoostrovskaya 13.Results and Discussion. Root fertilizers on the basis of nutrition diagnostics on the basis of soil and leaf petiole analysis made significant changes in the dynamics of basic nutrients in the soil, there was an increase in nitrate nitrogen and mobile potassium in comparison with the control variant, with natural soil supply of mobile phosphorus (more than 250 mg/kg), which had a positive effect on the root nutrition of plants. At the main application of mineral and organic (biocompost BIUD) fertilizers, root fertilizers according to nutrition diagnostics the carrot yield 51,2-63,9 t/ha with standard 87,4- 94,6%, red beet 41,7-54,2 t/ha with standard 80,7-92,3% were obtained. Root feeding of carrots by soil diagnostics N52K14 on the background of biocompost gave 24.9% increase to the control, by plant diagnostics N17 gave 16.6%; red beet by soil diagnostics N65K45 – 30% increase, by plant diagnostics N54K30 – 23.7%

Relevanse. A significant influence on the processes of growth, plant development and accumulation of tubers of potato varieties is a scientifically based and rational planting density, which allows the fullest use of the factors of light, air and mineral nutrition available in the field. The establishment of optimal planting density for new zoned potato varieties should be considered in close connection with other agricultural practices, as well as taking into account the purpose of growing products in specific soil and climatic conditions.Methodology. The research was conducted in 2018–2020 at the experimental base "Korenevo" of the Russian Potato Research Centre (Moscow region). The aim of research was to determine the optimal planting density for the new potato varieties of domestic selection: Gulliver (early), Azart (medium early) and Grand (medium ripe). Three planting densities were studied – 44 thousand tubers/ha (control); 50 and 56 thousand tubers/ha. Planting was carried out on May 4-6 with local application of mineral fertilizers at a dose of N90P90K135 two strings per ridge.Results. It was revealed that with the increase of planting density by 6 and 12 thousand tubers per 1 ha, the height of plants raised by 2-4 cm, depending on the variety on average over 3 years. The weight of the tops and the assimilation surface area of leaves increased, respectively, by 1.0-4.4 t/ha and 1.1-3.4 thousand m2/ha. The number of stems and tubers decreased, respectively, by 0.2-0.7 and 0.6-1.0 per bush. Increase of harvest due to higher plant density for the cultivar Gulliver was 2,2 and 3,1 t/ha, or up to 7,3%; for the Azart variety 2,8 and 3,3 t/ha, or up to 8,7%; for Grand variety 1,9-2,6 t/ha, or up to 7,8%, compared to control variant.

Relevance. Tomato pink-fruit cultivars and hybrids are of interest for fresh consumption. The biochemical parameters are influenced by the varietal factor and by the growing conditions. It is known that mature tomatoes record low storability. The softening of the fruit is caused by ethylene produced in the ripening fruit. Then pectinase enzymes are synthesized in the fruit tissues, under the action of which the cell walls of the fruit soften. Breeders are creating tomato cultivars whose fruits could be stored for a long time without losing their tasty.   The aim of the investigation was to study the biochemical parameters of pink-colored tomato fruits under different ripening conditions.   Materials and methods. The plants were grown on the experimental fields of the Laboratory for Breeding and Seed Production of Solanaceae crops. In the Analytical Department, the biochemical composition of pink tomato fruits was studied during harvesting from the field and after laying for storage in the milky ripeness phase according to the following indicators: dry matter, ascorbic acid, total content of water-soluble antioxidants, titratable acidity, monosaccharides, polyphenols and carotenoids.   Results. The breeding accession F4 (Lotos x Z6) showed maximum dry matter and monosaccharide content both after storage and in mature fruits. The same sample as F5 (Lotos x Z6) showed the highest ascorbic acid content after storage. Other parameters before and after storage in these samples were comparable. Whereas, breeding accession F6 (Z6 x Lotos) stood out in terms of maximum content of sum of antioxidants in alcoholic extract and content of water-soluble antioxidants after storage.

Relevance. Oenothera tetragona is an ornamental plant used in folk medicine. Until now, studies of the biological characteristics of the Oenothera tetragona have not been carried out on the territory of the NonChernozem zone of the Russian Federation.The purpose of the work is the introduction and biological study of the Oenothera tetragona in the NonChernozem zone of Russia in the conditions of the Moscow region.Methodology. The experiment was based on two-month-old seedlings according to a 60x30 cm pattern. Phenological observations and biometric measurements (during the mass flowering phase) were carried out according to the methods adopted at VILAR (All-Russian scientific research Institute of medicinal and aromatic plants). Experimental data were processed according to B.A. Dospehov. Weather conditions were checked on the Weather and Climate website. Microspecimens were prepared according to methods for light microscopy.Results. In the conditions of the Moscow region the period from the beginning of the growing season to mass fruiting in Oenothera tetragona Roth. averages about 110-115 days. The plant is well adapted: it goes through the entire seasonal cycle of growth and development. The population includes Oenothera tetragona Roth. includes many variable biotypes, which indicates the possibility of targeted selection of forms with useful traits. The main assessment of breeding material can be carried out, starting from the second year of plant life, based on a set of interrelated quantitative traits (height, number of generative shoots, etc.). Some anatomical features of the epidermis of the Oenothera tetragona leaf have been studied for the first time; the number of covering trichomes and the number of stomata per 1 mm2 were determined. As a result of microscopic examination of the epidermis of leaf plates of O. tetragona Roth.: the presence of three groups was revealed, which differed in microscopic characteristics (shape and number of stomata, pubescence) in the absence of a noticeable correlation with the main phenotypic characteristics.

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. The purpose of the research was to improve the elements of zonal agricultural technology for cultivating a new variety of sweet pepper Zarnitsa, to study the possibility of increasing productivity, reducing production costs during its seed production through the use of a non-seedling method of cultivation in irrigated conditions and the plant growth regulator Zircon, R.Methodology. Experimental studies were carried out on the experimental field of All-Russian Research Institute of Irrigated Vegetable and Melon Growing (Astrakhan region) in 2022-2023. The establishment of the field experiment and the carrying out of records and observations in the experiment were carried out in accordance with generally accepted methods.Results. It was found that with the seedless method of growing sweet pepper, the period from sowing to the start of fruit harvesting was 12 days shorter. Sweet pepper plants in the seedling method during the fruiting phase had advantages: in plant height by 9.3%, in the number of lateral shoots by 21.2%, in leaf weight by 7.0%, in average fruit weight by 6.1%. The highest yield, on average 31.6 t/ha, was obtained using the seedling method; when sowing seeds in the ground, it was 3.8% lower. Replacing the seedling method of cultivation with a non-seedling method contributed to a reduction in production costs by 74.7 thousand rub./ha, production costs by 1.9 thousand rub./t, production profitability by 1.2 times, due to savings in labor resources and working capital for growing and planting seedlings. Replacing the seedling method of cultivation with a non-seedling method helped reduce production costs by 74.7 thousand rub./ha, production costs by 1.9 thousand rubles/t, the profitability of production of sweet pepper products and seeds by 1.2 times, due to savings labor resources, working capital for growing, planting seedlings. A single treatment with the plant growth regulator Zircon, P (30 ml/ha) at the beginning of flowering contributed to a significant increase in plant biometric parameters: height by 12.2%, number of lateral shoots by 30.8%, leaf weight by 14.3%, yield by 2.4 t/ha (7.9%), compared to the control (30.4 t/ha), an increase in sugar content by 0.2%, vitamin C by 4 mg% and seed yield by 9 kg/ha (8.7%). The sowing qualities of sweet pepper seeds in all variants of the experiment met the standard requirements and were – 94-95% in terms of germination and – 92-94% in terms of germination energy. The highest level of profitability of 204.9% was obtained as a result of using a growth regulator; in the option without treatment it was lower by 14.4%.

Vegetable chips are extremely popular due to high content of antioxidants, valuable biological activity and long-term storage. During the investigation optimal methods of drying and chips storage from celery (Egor and Dobrynya cvs), parsnip (Krugly, Bely aist and Zhemchug) and parsley (Zolushka cv) roots were developed using the criteria parameters of taste, aroma, color and antioxidant content. The highest organoleptic properties were recorded for celery chips of Dobrynya cv, parsnip chips of Krugly cv and root parsleyThe highest differences in chips organoleptic parameters between convectional and freeze-drying methods reached 1.5 times for parsnip Bely aist cv. while the lowest differences were recorded for root parsley (1.05 times). Decrease in antioxidant activity during freeze-drying was the lowest in root parsley and celery Dobrynya cv. Convectional drying did not affect chips total antioxidant activity and demonstrated the highest preservation effect after 8 months storage. On the contrary, vitamin C losses were the highest during convectional drying though during storage vitamin C content in such chips decreased much less than in freezedried products. Aluminum foil provided 1.2-1.8 times higher content of antioxidants than paper and polyethylene package. Significant inter species and varietal differences in antioxidant stability during various methods of drying and storage were revealed.

Relevance and methodology. The task of controlling the growth and development of sugar beet plants with the help of lighting devices is of interest from the point of view of identifying biological features of the culture and in breeding practice. The purpose of the research is to determine the response of plants to the effects of low–energy monochrome radiation at the initial stage of ontogenesis (germination of seeds (coplodia) sugar beet). In this regard, the seeds of the hybrid Smena were germinated in the dark (control) and under different variants of continuous illumination with wavelengths of 380 nm, 440 nm, 525 nm, 660 nm and 730 nm.Results. The reaction of sugar beet seeds and sprouts to illumination with monochromatic light depends on the wavelength Germination of seeds when irradiated with monochromatic far-red light leads to a decrease in germination energy by 23%, seed germination by 39%, the height of sprouts and aboveground biomass by 21.8% compared with the control (dark germination). Similar indicators were observed for the negative effect of red light. Exposure to UV-A light (380 nm) led to an increase in germination energy by 4%, but germination, on the contrary, decreased by 12%. The terrestrial biomass of sprouts also decreased (by 9.9%). Irradiation with green and blue light had a positive effect on growth: the terrestrial biomass of sprouts increased by 19.8% with a green spectrum and 7.3% blue. At the same time, there was no decrease in germination energy and germination compared to the control. The germination energy under the influence of blue light even increased by 12%. With dark germination, elongated etiolated plants were formed on the 10th day, whereas in the variants of green, blue and UV-A irradiation, harmoniously developed dark green shoots were formed.

Solanum tuberosum L. is susceptible to 40 different virus species and 2 viroids. To prevent plant viruses from spreading in field conditions, it is necessary to have reliable data on the species composition of plant reservoirs of viral infection, the total activity of insect vectors, and possible ways of virus transmission in a particular territory of seed material production. Attention should be paid to the factors that facilitate and hinder the disease development in crops and to disease symptoms in different potato varieties. Manifestations of viral infections were monitored on every plant from the sample at the stages of initial growth, bud formation, and flowering and before the removal of potato haulms. Insects were collected using standard entomological method. The total RNA was isolated employing commercial kits for the extraction of nucleic acids from plant material “PhytoSorb” (Syntol Llc) and the benchtop automated extraction instrument KingFisher Flex (ThermoScientific) with magnetic particles. Plant viral infection was observed to accumulate if potato planting material was not renewed. The tested potato plants contained mixed viral infection, which consisted of viruses from mosaic group: PVY, PVX, PVM, PVS PVA, as well as PSTVd and PLRV. Without the renewal of seed potatoes, the concentration of plant viruses in an agroecosystem rises and causes secondary infections in potato plants. The research identified the main insect-vectors in the agroecosystem of potato fields: insects from genera Cicadella, Henosepilachna vigintioctomaculata, Dolycoris baccarum, Mythimna separata, Lygus pratensis, and Rhopalosiphum padi. Many wild weeds serve as fodder plants for insect vectors facilitating the accumulation of plant viruses in agroecosystems. It was established that perennial weeds were the main plant reservoirs of dangerous viral infections, e.g. Sonchus arvensis and Taraxacum officinale. We determined that Trifolium pratense typus L., Chenopodium album L., Plantago major L., Barbarea vulgaris W.T. Aiton, and Ambrosia artemisiifolia L. were the reservoirs of PVY. All these factors can lead to an epiphytotic situation.