Relevance. This article presents the results of a study of the process of sucrose inversion in vegetable and fruit monocomponent purees with and without sucrose under the influence of ultrasonic action on them.Methods. For the study, experimental samples of carrot, pumpkin and Apple puree of two types were made – a monocomponent natural puree (without sugar) and puree with the addition of 5% sucrose (by weight). The main part of the study was to study the depth of sucrose inversion in experimental samples, depending on the specified parameters of ultrasound exposure at a frequency of 21.6 kHz for 30 minutes on a laboratory cavitation unit in a flow-through cyclic mode.Results. It was found that in all experimental samples, the amount of total reducing sugars increased significantly compared to the values obtained in control samples that were not subjected to ultrasonic treatment. So, in natural apple puree (without adding sucrose) after ultrasound exposure, an increase in total reducing sugars was detected by 9.3%, and in experimental samples of apple puree with added sucrose – by 10.9%, in relation to control samples, which is 1.2 times higher than in natural puree. In samples of carrot puree (without adding sucrose), the increase in total reducing sugars was 6.7%, and in puree with added sucrose, the increase was 12.2%, which is 1.8 times higher than the inversion in puree without sugar. In samples of pumpkin puree without sugar, the increase in reducing sugars was 4.2%, and in samples with added sucrose – 9.9%, i.e. 2.4 times higher than in samples without sugar.These data allow us to conclude that ultrasound exposure can intensify the inversion of sucrose with an increase in the number of reducing sugars, and this process takes place more deeply in products containing added sucrose.

Relevance. Currently, there is a problem of satisfying the demand in the domestic market for fruit and berry products in accordance with current recommendations. One of the ways to intensify agricultural production is the use of resource-saving technologies, which include drip irrigation. The issues of regulating the water balance of the soil when growing planting material for fruit crops in modern conditions require experimental studies aimed at studying the biological characteristics of economically important plants and their reactions to the complex of external environmental factors.Methods. Field studies were conducted on the territory of the educational experimental farm of the Michurinsky Garden fruit growing laboratory of the Russian State Agrarian University - Moscow Timiryazev Agricultural Academy. A two-factor experience in the study of different ranges of moisture for the formation of varietal plum seedlings grafted on plum tree stock was laid in the spring of 2018. The first factor included options for maintaining soil moisture in the range of: 1) 60-80% of the lowest moisture capacity; 2) 70-90% of the lowest moisture capacity; 3) 80-100% of the lowest moisture capacity; 4) control (without irrigation). Plum varieties “Mashenka” and “Utro” were the second factor.Results. Constructed humidification contours according to the years of research and experimental options showed that drip irrigation contributes to the optimum moisture concentration in the soil for seedlings. The most developed root system compared with the control was obtained on irrigated options with maintaining humidity in the range of 70-90 and 80-100% of the lowest moisture capacity. Here, the maximum values of the volume of the root system, the number of roots and the average root length are obtained. It was revealed that in the variants with irrigation, the root system of seedlings spreads in the upper layer (mainly 20-30 cm) and stretches along the line with droppers.

Relevance. Late blight (Phytophthora infestans Mont. de Bary) is one of the most harmful, rapidly spreading potato fungal diseases, which dramatically reduces its yield and affects tubers during storage. The quantitative manifestation of partial resistance within the same potato variety depends on meteorological conditions and the infectious load. Therefore, its objective assessment is obtained when testing varieties in regions that are stably favorable for the development of pathogens (Sakhalin Island and central Mexico), or in standard laboratory conditions using climatic chambers and molecular genetic methods. The aim of this work was a laboratory assessment of the potato varieties and hybrids resistance to late blight.Methods. Data on laboratory assessment of the potato varieties and hybrids resistance to late blight are presented. The experiment was carried out using generally accepted methods for the study and assessment of the potato varieties resistance to phytopathogens with minor modifications.Results. It was established that the varieties Smak, Yantar, Dachny and Kazachok are medium susceptible to late blight, as shown in the Catalog of varieties. In the variety specimen Pri-12-35-4, with a low degree of necrosis and sporulation development, slices showed damage to 50% of the tubers surface with active sporulation and maturation of double-flagellated zoospores. Hybrids Pri-11-12-5, Pri-12-18-7 showed a high score for the development of necrosis and sporulation with a slight excess to these indicators for tubers (1.17-1.05 times). Among hybrids and varieties of potatoes, a sample of Pri-11-31-24 stood out, with an average score for sporulation and slice necrosis of 1.44 and 1,42, respectively, for tuber damage - 1,72.

Relevance.Extract-based compositions, combining various types of biological activity were created and tested, to reveal the potential of genus Rheum (Polygonaceae)plants bioactive substances. The aim of the work was to determine the composition of bioactive substances in R. rhaponticum L. plants extracts and assess the possibility of their use as a means of protecting vegetable plants from powdery mildew.Materials and methods. The methods of cultivation and research of R.rhaponticum plant materials was carried out at the Institute of Genetics, Physiology and Plant Protection, Chisinau, Republic of Moldova (2012-2019). The subject of our study the bioactive substances of rhubarb roots and leaves were used. Results.The localization zones of anthracene derivatives were identified: in the main parenchyma of the secondary cortex and the parenchyma of the core rays of the rhubarb root. The amount of flavonoids and phenols in the root extract is 2 times more than in the leaf extract. To study the fungicidal and stimulating properties of rhubarb root extract in the control of powdery mildew, we conducted studies in a greenhouse on vegetable plants using artificial infection of seedlings. It was found that the chlorophyll transmittance index of leaves treated with rhubarb root extract increases until the concentration of the extract (R) reaches 1.5% (157.3 rel. units)(In the control – 119.2 rel. units). With increasing concentration of the extract to 2%, the chlorophyll index falls 1.2 times lower than the control values. The highest immunostimulating and fungicidal activity, intensifying with the addition of rhubarb leaf extract, was shown by rhubarb root extract. Its biological effectiveness was high at any intervals between treatment and infection (4 and 72 hours), and was directly proportional to concentration. Adding rhubarb leaf extract to the rhubarb root extract enhances the activity of the composition, and the risk of developing pesticide resistance among plant pathogens decreased.

Relevance. A priority in the selection of watermelon is the creation of new competitive varieties that combine resistance to adverse stressors, high yield and excellent fruit quality. The purpose of this study is to show the influence of weather conditions on the growing season, yield and quality of watermelon fruits and the influence of growing conditions on the growth and development of watermelon plants.Materials and methods. The study used 5 varieties of watermelon included in the State Register and 2 new varieties, ready for transfer to the State Variety Test. During the research, all observations and counts were carried out in accordance with the State Variety Testing Methodology and the Field Experience Methodology.Results. In the process of research, it was found that the length of the growing season largely depends on the amount of precipitation and the sum of active temperatures, as well as on their distribution in interphase periods. It was noted that in the year with the highest rainfall, the growing season was the longest. Productivity for the analyzed period varies from 14.2 t / ha to 20.7 t / ha in the early group, from 19.4 t / ha to 24.9 t / ha in the average. The highest yields were recorded in 2017 with the least rainfall. Growing conditions had a significant impact on the quality of watermelon fruit: the solids content ranged from 9.4% to 12.8%, total sugar - from 7.70% to 11.35%.

Modern crop cultivation technologies have reached the limits of “saturation” both in the ecological (environmental pollution, suppression of the mechanisms of its self-regulation), energy (exponential growth of irreplaceable energy costs for each additional unit of production), and in production. In this regard, environmental factors (air drought, frosts, active temperatures, etc.), which cannot be optimized, are becoming increasingly important in ensuring a steady increase in the yield of cultivated plant forms. In recent decades, more and more attention has been paid to technogenic and biological systems of agriculture, based on the ecologization and biologization of the intensification processes of adaptive crop production. Such approaches are the precision agriculture system (PA) and QTL analysis. Using these approaches allows not only to ensure a steady increase in productivity due to the combined use of the advantages of precision farming and molecular genetic assessment, including the creation of new forms and varieties that are responsive to РА agricultural practices, but also to level the negative impact of abiotic and biotic environmental factors that limit the size and quality of the crop as well as plant productivity. It is shown that the strategy of adaptive intensification of crop production through the use of the TK system and QTL analysis approaches is not alternative to existing farming systems, however, it focuses modern agriculture on the growth of knowledge-intensive agricultural production as a whole. An analysis of the causes under consideration, the current unfavorable trends in modern crop production and agriculture, clearly shows their scale and long-term nature, and therefore the inevitability of the search for new priorities for intensification of crop production and agriculture, providing a qualitatively new stage of their development in the interests of man.

Relevance. Vertical farming – is a new and advanced direction in greenhouse vegetable cultivation. Expansion biodiversity of plants for vertical farming occur with help of green leafy vegetables. Plants of Lamiaceae family are well known as aromatic and medicinal plants with high content of substances with antioxidant activity. It allows use these plants as a base for the functional nutrition. Leafy parts the plants of Lamiaceae family may be used as aromatic and healthy additions to traditional foods, such as salads, soups and sauces.  Goal of the study: analysis the biochemical composition of leafy parts plants of Lamiaceaefamily, cultivated at the multi circle hydroponic construction. Materials and methods. 1) Plants: Monarda fistulosa L. (the breeding sample №5 U.P.), Monarda citriodora Cerv. ex Lag. (Simka variety), Melissa officinalisL. (Zhemchuzhina variety). 2) secondary metabolites: flavonoid glycoside linarozid and steroid glycoside moldstim. Methods. 1) cultivation of plants Lamiaceae family at the 5 circles hydroponic construction; 2) analytic methods: determination of dry matter content, determination of ascorbic acid content, determination sum of chlorophylls and carotenoids, determination sum of antioxidants; 3) statistical methods. Results. First experiment the cultivation of plants Lamiaceae family at the multi circle hydroponic construction was successful. Location of plants at different circles of hydroponic installation didn’t influence the content of dry matter, ascorbic acid and sum of chlorophylls in leafy parts of plants Monarda fistulosaL. The content of dry matter and sum of antioxidants in leafy parts of Monarda fistulosaL. plants of the first cutting is significantly higher than of other cuttings. So, we can recommend the leaves of Monarda fistulosa L. plants of the first cutting for the healthy additions in the scheme of the functional nutrition. Seed treatment with water solutions of secondary metabolites changed significantly the weight of leaves: it was increased in Monarda citriodoraCerv. ex Lag. and in Melissa officinalisL.

Relevance. High lycopene fruit content has been regarded as a very important genetic trait in tomato breeding. Use lycopene molecular markers in combination with conventional breeding techniques allowed us to create hybrids with high lycopene accumulation, excellent organoleptic qualities, high yield production and resistance to pathogens, and to effectively optimize our breeding programmes for commercial greehouses production.Material and Methods. In this study tomato samples including selected lines and hybrids with various allelic combinations of genes determining carotene accumulation, and other genetic traits, such as disease resistance and yield production were tested. Introgression of spontaneous and induced mutations was used to increase carotenoid levels (og and hp) and improve fruit technological qualities (nor, alc, rin). The research material was tomato collection, mutants, breeding lines and hybrids listed in the State Register Russian Federation tomato hybrids of breeding SS Agrofirm "Ilyinichna" VNIIO branch of the All-Russian Scientific Research Institute of Vegetable Growing – Branch of the FSBSI Federal Scientific Vegetable Center. DNA typing of fruit quality genes was performed at the Institute of Genetics and Cytology of the National Academy of Sciences of Belarus.Results. New domestic hybrids for industrial greenhouses, which characterised by improved organoleptic qualities and technological traits were developed with the help of phasedcross-breeding that allowed to combine the genes nor, rin, alc, leading to an extension of the shelf life with the genes B, og, hp1, etc., contributing to an increase in carotenoid content in fruits. It was established that for targeted selection and hybridization, despite the negative influence of the nor, rin, alc genes it is possible to raise the level of carotenoids to average values. Correlation between lycopene concentration in fruits and high temperature and level of insolation was confirmed. It was shown that pink-fruited forms contain significantly more lycopenethanred-fruitedones. Different all eliccombinations of structural genes involved in carotenoids biosynthesis and regulatory genes that provided maximal accumulation of lycopene in hybrid swithred and pink fruits were revealed. Hybrids with the combination of high concentrations of sugar (° Brix), dry matter and maximal lycopene values, combined defining excellent taste were selected: Prekrasnaiya lady, Olya, Quadrille, Victoria. New F1 hybrids one for industrial greenhouses: G950, G956, G960, Magistral and pink fruited G12897, surpassed the Dutch standard in productivity up to 21%, and in tastes/organoleptic qualities for 1-1.8 points.

Relevance. Plant growth biostimulants based on natural raw materials are ecologically safe and harmless to humans. Stevia (Stevia rebaudiana Bertoni) contains in its leaves sweet diterpene steviol glycosides, which are similar in structure and properties to gibberellins, as well as a number of other valuable biologically active compounds. Water extracts from stevia leaves are capable to accelerate growth, to increase the yield and quality of plants. However, further study and development of application technologies of the extracts for specific crops and different growing conditions are required. The purpouse of this work is to investigate the effect of an aqueous extract from stevia leaves on the yield and quality of lettuce and small radish under photoculture conditions. Materials and methods. The objects of the study were lettuce var. Typhoon and small radish var. Riesenbutter. The plants were grown in photoculture at the biopolygon of the FSBSI Agrophysical Research Institute (St. Petersburg) at an illumination of 10–20 klx, a temperature of 22–26°С (day) and 18–20°С (night). Watering was carried out with water, top-dressing was carried out with Knop's nutrient solution three times a week. Peat with mineral additives was used as a substrate. The original extract was prepared by extraction from stevia dry leaves powder with hot water (80°С) in a ratio of 1 g of leaves: 100 ml of water. Foliar treatment of plants was carried out twice at dilution of the original extract from stevia leaves 1:10, 1:50, and 1:100 (extract : water) at the rate of 0.20-0.25 ml / lettuce plant and 0.09-0.1 ml / radish plant; control plants were treated with water. The data were processed according to standard procedures using the Excel 2016 software. Results. Foliar treatment with an extract from stevia leaves did not significantly affect the size and weight of radish root crops, but increased the yield due to a decrease in the number of bolting plants. A significant decrease of bolting was observed in all treatment options (by 34-51%). When using a dilution of 1: 100, the yield of marketable root crops increased by 20% and the yield per sq. m. – by 25%. Foliar treatment with stevia extracts increased the mass of lettuce plants, as well as their biological value. The content of photosynthetic pigments, sugars, and vitamin C significantly increased, and a tendency towards a decrease in the content of nitrates was observed. According to data, we recommend for foliar treatment are dilutions of the original extract 1:50 and 1: 100. The effect of using of an extract from stevia leaves is similar in action to some biostimulants from plants with hormone-like properties, which determines the possibility of using it as a safe plant growth stimulant.

Relevance. In the Republic of Moldova in recent years, during tomato flowering, air temperature reaches 35°С and higher, which significantly reduces fruit set, yield and product quality, therefore, the creation of varieties resistant to temperature stress is of particular importance. The relevance of the studies is due to the need to identify tomato genotypes resistant to high temperatures, to identify the genetic nature of the variability and degree of inheritance of tomato growth organs when interacting with different temperature conditions. The purpose of the research is to determine the effect of stress temperatures on the organs of growth and development of tomato plants at an early stage of ontogenesis, the degree of genetic, phenotypic variation and inheritance of characters. Materials and methods. The research material was 5 promising lines of tomato with high economically valuable traits. As a standard, a omologated variety Mary Gratefully was used. Four temperature levels were used – optimal (25°С) and stress (38, 40 and 42°С). The length of the germinal root and stem of 7-day-old plants was measured. The experiment was made in 3 replicates. The following were studied: genetic and phenotypic variants, heritability coefficient, phenotypic and genotypic coefficients of variation, genetic progress. The data were processed in the STATISTICA 7 software package. Results. As a result of the studies, a significant differentiation of the reaction of tomato genotypes to temperature stress was revealed. A significant effect of temperature on the genetic and phenotypic varieties of signs of growth and development of tomato plants, heritability in the broad sense, genotypic and phenotypic coefficient of variation, and genetic progress have been established. Of a great interest for further studies are the Mary Gratefully, L 304, L 306 genotypes, which are highly resistant to the studied traits.