Potato (Solanum tuberosum L.) is a fairly popular agricultural crop in Russia, the tubers of which are the main food of the population. For the North, it is important to replenish the assortment of early potato varieties adapted to growing in extreme conditions. The aim of this research was to study the development of plants of early and mid-early potato varieties in the Murmansk region.Methods. The article presents the results of studying the developmental biology and productivity elements of 63 early and mid-early varieties from the of VIR world potato collection. The Khibinskiy ranniy variety is used as a standard. The study was conducted on the territory of the Polar Experimental Station of Apatity. The soil of the experimental plot is sandy loam, highly cultivated, the organic matter content is 8,7%, pH 5,2; Р2О5 – 103 mg/100 g, К2О – 39,2 mg/100 g of soil. The total area of the plot was 286,5 m2 , the counting area was 5 m2, the planting scheme was 70x30 cm, the experiment was repeated three times, the distribution of varieties was randomized.Results. Phenological observations revealed varieties with the shortest interphase periods: Ognivo, Sundinsky ranniy, Uralsky ranniy, Khibinskiy ranniy, Amazone, Aster, Lady Claire. Varieties Daryonka, Lyubava, Dolphin formed berries within three years.Conclusion. Concorde, Corine и Karatop exceeded the standart at 50, 60, 75 days from planting in the years of study, which shows the ability of the cultivars for intensive tuberization in the early stages, combined with high stable productivity in the North. The significant influence of meteorological conditions on the development dynamics of potato plants, their yield and on the adaptive ability to local growing conditions has been identified. There singled out the cultivars that are characterized by consistently high rates of the dynamics of tuber accumulation in the early stages, possessing a high adaptive ability, which can be used in breeding for early maturity and productivity in the North regions.

Weeds are a major threat in crop production, and controlling them in modern agriculture is critical to preventing crop losses and ensuring food security. Intensive farming practices, climate change and natural disasters affect weed dynamics, requiring a change in management practices. Existing methods are no longer viable due to lack of manpower; chemical control methods are limited by health hazards and the development of herbicide resistance in weeds. This article discusses some potential alternative weed control strategies in modern vegetable production that are feasible and effective. Increasing the competitiveness of vegetable crops through proper planning of agrotechnologies system, preventive, cultural and mechanical methods, development of competitive varieties, allelopathy, biological control and reduction of weed seed production at harvest will be a major aspect in sustainable weed management. Improving tillage regimes has long been considered the main measure of weed control. Control of weed seed production and weed injuriousness have been shown as potential tools to reduce weed seed germination and retention in the soil. The development of allelopathy has led to the emergence of new methods of weed control. The use of the allelopathic potential of crops also deserves mention in modern weed control methods. Thermal weed control is seen as a useful method. The role of bioherbicides as an integral part of sustainable weed management is emphasized. All of these strategies are viable for modern agriculture; however, choosing a specific method and using the right combinations will be the key to success. No strategy is perfect, and therefore an integrated approach can provide the best results. The adoption of such practices can improve the efficiency of farming systems in sustainable agricul- ture. A comprehensive method for protecting vegetable crops from weeds and ways to reduce the potential contamination of fields with seeds and weed seedlings are described. The optimal norms and technological features, conditions for the effective use of modern herbicides on crops and plantings of vegetable crops are given.

Relevance. Peanut seeds are rich in oils, protein, carbohydrates, vitamins and flavonoids, therefore they are widely used in the production of food, feed, biodiesel, as well as in medicine. When cultivating peanuts, the problem of reducing the yield and sometimes the quality of seeds necessarily arises due to the impact of phytopathogenic microscopic fungi, and the main factors in the transmission of the infectious principle are soil and plant residues. The plant protection system should be based on knowledge of the structure of mycocomplexes of the rhizosphere and phylloplane.Methods. On a typical black soil on a natural infectious background in Belgorod (Russia), a sample of cultural peanuts V-2012 (Vietnam) from the collection of the Department of Biotechnology and Microbiology of the Institute of Pharmacy, Chemistry and Biology of the National Research University "BelSU" was studied. The species composition of microscopic fungi in the peanut rhizosphere was analyzed in comparison with fallow soil (control), which was found by seeding soil dilutions and leaf samples on dense nutrient media, followed by identification to species.Results. Compared with the control soil, the mycocomplex of the peanut rhizosphere (the Shannon index value at the level of 2.5 and 2.7 in the rhizosphere and control, respectively) was characterized by a lower degree of diversity and the degree of similarity of soil samples was high (the Jaccard coefficient was 50%), which means that that the cultivation of peanuts has lit- tle effect on the composition and structure of a typical black soil. In the peanut rhizosphere, a decrease in the frequency of occurrence of the phytopathogenic species F. oxysporum was observed, which may be associated with an increase in the rank in the mycocomplex of the mycophilic species T. lignorum. Aspergillus ochraceus, A. terreus, A. ustus, Candida albicans, Curvularia lunata, Fusarium oxysporum, Trichothecium roseum species were found to be sen- sitive to peanut cultivation. Peanut leaf spot was caused annually by the species Alternaria alternate, which can lead to a decrease in seed productivity up to 80%.

Relevance. Anthocyanin pigments can be synthesised in the stem, leaves, calyx, peel and pulp of tomato fruit. These compounds protect the photosynthetic apparatus of the plant, neutralise free radicals, increase the efficiency of phosphorus and nitrogen assimilation, have an osmoregulatory function, antimicrobial activity and increase the level of adaptation to unfavourable environmental conditions. In addition, anthocyanins from plant foods play an important role in the prevention of type II diabetes, neurodegenerative processes, cardiovascular and infectious diseases. Therefore, the cultivation of tomatoes with anthocyanin-coloured fruits is a perspective area for the vegetable industry in Russia. Vegetable products containing antioxidant substances belong to the functional products and conform to the concept of a healthy diet. As one of the most popular and frequently consumed vegetable crops, the anthocyanin content of tomato is advisable to increase in the fruit (peel and pulp).Material and methods. In this work we studied breeding samples of FSBSI FSVC: L-Ch-365, L-IR-2080, L-Zemba, hybrid combination F1 Zemba x L-Ch-365, variety of Siberian Botanical Garden Bosare blue. The aim of our research was to determine the quantitative composition of phenolic compounds - anthocyanins in different tomato samples, and on this basis to determine the objectives of breeding to improve the content of phenolic compounds.Results. As a result of the research, the quantitative content of anthocyanins in fruits of dif- ferent tomato specimens has been studied, on which the dietary and medicinal quality of the fruits depends. The sources of high content of anthocyanins (L-Zemba, L-IR-2080) have been obtained, which will make possible to conduct directed breeding work for high content of phenolic compounds. It has been shown that anthocyanin-rich tomato samples can be rich in carotenoids, which gives an opportunity to create new varieties and hybrids with high content of water- and fat-soluble antioxidants. Potential samples for breeding according to the complex of biochemical indicators have been identified: L-Zemba, L-IR-2080, Bosare blue. It has been shown that selection for high content of anthocyanins can be performed at various stages of fruit ripening (large ripe fruit, blangetongue, biological ripeness), selecting the most intense colouring. The Zemba tomato variety developed at FSBSI FSVC has a sufficiently high anthocyanin content and is recommended for cultivation in production.

Relevance. The use of non-invasive photometric methods for assessing the stress states of plants makes it possible to assess the physiological state and resistance of plants.Material and methods. In small-field and vegetation experiments, we studied the photometric indicators of the physiological response of potato varieties (reflection coefficients in different ranges) to nitrogen stress created by five doses of fertilizers using contact (N-tester) and remote (N-sensor) methods.Results. Potato varieties released for the conditions of the North-Western region of the Russian Federation were studied for their ability to withstand stress provided by low and high levels of nitrogen nutrition of plants and different weights of planting tubers. The resistance of plants of different genotypes to external and internal stressors was studied by the reflection coefficients measured in 4 channels, which characterized the differences in the physiological state of plants. Ensuring the potential genotypic resistance of the organism in the form of a decrease in FIS F1,3 corresponds to the inclusion of various mechanisms of plant adaptation to external or internal influences, depending on the genotype. In the vegetative experiment, of the studied photo-optical reflection coefficients, the most informative were the FIS F1,3 indicators, which showed that the overall viability of such varieties as Peterburgsky, Charodey and Kholmogorsky turned out to be increased. The reaction type of the Kholmogorsky variety is the most promising for growing plants under stress conditions.

Turnip, Brassica rapa L. subsp. rapa is the oldest vegetable crop in Russia. Turnip varieties are fastgrowing, productive, have valuable biochemical properties, cold-resistant, relatively easy to grow. To expand the vegetable assortment, new varieties and hybrids should be created, first of all, the types of varieties that are not in the State Register of Russia. The purpose of the work: using the data of a long-term study of the VIR collection to identify valuable material for breeding.Methods. Field study of 170 samples of the VIR collection was carried out in the NPB "Pushkin and Pavlovsk laboratories of VIR" (Leningrad region) in 2001-2020. Sowing was carried out on June 26- 28. Each sample was sown on a single-row plot 2 m long in three repetitions. As a control, turnip varieties included in the State Register were used – the variety of leaf turnip Sapphire, the table turnip variety Petrovskaya-1 and the fodder turnip variety Osterzundomsky. The description was carried out according to the Methodological Guidelines for the study and maintenance of the VIR world collection, with author's additions.Results. The best leaf turnip samples, found during the study has a large plant mass (up to 1.42±0.32 kg in the Early top F1 sample (k-366, Japan), many samples exceeded the Sapphire standard for this trait. Some of the samples of table turnips also exceed the Petrovskaya-1 standard by weight of the root (Purple top (k-1345, Nepal), Pekki (vr.2176, Finland)). Samples Solovetskaya (k-803, Russia, Murmansk region), Gul Findlandsk (vr.2175, Norway) have a bright yellow flash of the root, are easy to store and resistant to damage by cabbage flies. Among the turnip samples distinguished by yield (Table 5), the most interesting are the turnips Ova Dæhnfeldt (vr.2183, Denmark) and Korova (vr.2187, Sweden), which have yellow flesh and an increased content of β-carotene in roots.Conclusion. It was possible to identify new samples belonging to groups of leaf and root turnips, that are not represented on the seed and food market of Russia. Such samples belong to morphologically different forms, are productive, carry a complex of valuable economic and biochemical characteristics and are perspective material for inclusion in programs for the selection of leaf and root crops.

Relevance. In the central zone of the Krasnodar Territory, the mobility and availability of the main elements of mineral nutrition can be limited in certain phases of the growing season of melons and gourds, especially with a decrease in soil moisture and high temperatures. An important additional and corrective element of nutritional technology is foliar feeding, which increase the absorption of fertilizers during critical periods of plant growth and development.Material and methods. The purpose of the research is to determine the effectiveness of foliar application with organic fertilizer AGROCHELATE to maximize the biological potential of watermelon varieties on seed plots during summer sowing. The research was carried out at the seed-growing area of the vegetable growing department in the "Federal Scientific Rice Centre" in 2020-2021. The object of research was selected varieties of watermelon selection “Federal Scientific Rice Centre” Tersky early and Yubilyar with a growing season of 65-75 days. Organic fertilizer AGROCHELATE was used to treat the leaf surface of plants with a consumption rate of 100 ml/ha. A single spraying was used during the flowering phase of the plants. For the isolation of seeds, fruits were selected that were characteristic of the varietal phenotype in the phase of biological ripeness: in shape, size, color and pattern of the bark, color of the pulp, size and color of seeds.Results. In the Terskiy early variety, during spring sowing, fruits weighing 3.5-4.0 kg are formed. With summer sowing, the weight of fruits was significantly inferior and did not exceed 2.36 kg. The size of the Yubilyar watermelon fruit corresponded to the declared varietal parameters. The use of foliar application with organic fertilizer AGROCHELATE during the flowering phase did not affect the fruit weight. Analysis of the results of the content of dry soluble substances (DRS) in the pulp of the fruits showed a positive varietal response to the use of feeding. The share of influence on the improvement of the pulp quality indicator was 64.1%. On seed plots, after application of fertilizing with organic fertilizer AGROCHELATE, 0.81-3.09 t more than from control plots, selected fruits corresponding to varietal characteristics. The seed yield is largely influenced by the number of fruits selected for seed isolation. A one-time application of sheet processing made it possible to select a larger number of fruits on the Tersky Early variety - by 289 pieces./ha, on the Yubilyar variety – by 495 pcs./ha. Treatment of plants with organic fertilizer AGROCHELATE in the flowering phase contributed to an increase in the number of seeds in each fruit in the Tersky early watermelon by 19-127 pieces, in the Yubilyar variety by 9-111 pieces, respectively. Unripe seeds in fruits by varieties were 0.9-5.0% less than in untreated plants. In general, watermelon seeds obtained during summer sowing, regardless of the use of agricultural practices, corresponded to the elite category that can be used to grow marketable products.

Melon (Cucumis melo L.) is the most spread melon crop in Uzbekistan. More than 130 local varieties of melon are cultivated in various regions of the republic. Every year melons and gourds are cultivated on the area of 150 thousand hectares. The most harmful diseases of the melon are powdery mildew and Fusarium wilt. All local varieties of melon are susceptible to these diseases. Annually from these diseases, the yield of melon is reduced by 20-25%. The most effective way to combat these diseases is to develop resistant varieties. The Research Institute of Vegetable, Melon Crops and Potato has carried out long-term selection work to create melon varieties resistant to powdery mildew and Fusarium wilt. Breeding local varieties of melon with economically valuable traits and high test quality with genes for resistance to these diseases have been created and included in the State Register of Uzbekistan.

Timeliness. Currently, the Russian Federation has a high demand in healthy planting material of garden strawberries. The benefits of using fertilizers when growing strawberry seedlings have been proven by numerous studies. However, a comparative study of the effect of new fertilizers and methods of their application is very limited. In this regard, studies aimed at identifying the effectiveness of the use of prolonged-acting fertilizers in the production of garden strawberry planting material in protected soil conditions are relevant.Methods. Adapted to non-sterile conditions, ex vitro healthy garden strawberry plants were planted in a peat substrate of Veltorf LLC (recipe No. 5c/2) with the addition of Pg mix starter fertilizer with the structure NPK 14-16-18 + microelements (1.5 g/l of substrate). At the same time, prolonged-acting fertilizers were introduced into the substrate in the recommended concentrations: FertiPro Gran 1M (1.25 g/l of substrate), Ruscote 5-6M (3.0 g/l of substrate), Basacote Plus 6M (4.0 g/l of substrate), control peat substrate without fertilizers, PG mix standard.Results. It has been established that for the Karmen crop with an average runner-forming ability, the effectiveness of applying FertiPro Gran 1M fertilizer to the substrate was revealed, with the use of which, on the 180th day of cultivation, the number of runners and rosettes increases by 3.5–3.8 times compared to the control. At the same time, the yield of marketable seedlings is 95% compared to 70% in the control. For the Jūnija smaids crop with a high vine-forming ability, the effectiveness of all experimental variants with the application of FertiPro Gran 1M, Ruscote and Basacote Plus fertilizers to the substrate was revealed, with the use of which, on the 180th day of cultivation, the number of runners and rosettes increases by 1,9-2,5 times compared to the control. At the same time, the yield of marketable seedlings is 94-96% compared to 65% in the control.Conclusion. The introduction of long–acting fertilizers FertiPro Gran, Ruscote and Basacote Plus into the peat substrate with the addition of Pg mix starter fertilizer allowed a 2.3 – 3.8-fold increase in the number of runners obtained and 1.9-3.5-fold increase in the number of sockets obtained compared to the control without fertilizers.

Actuality. The opposite arrangement of the first two leaves in cucumber seedlings can be attributed to undesirable morphoses. The task was set: "To find out how often this sign occurs in cucumber seedlings and whether it is transmitted in the next generations during seed propagation."Material and conditions. The research was carried out on the cucumber breeding material of the laboratory of selection and seed production of pumpkin crops (100-142 samples) on the basis of the Federal Scientific Vegetable Center in 2019-2021 in the Moscow region in the conditions of the seedling department of the winter greenhouse. Sowing of cucumber seeds for seedlings was carried out on January 10-13, March 15 and May 5. Seedlings were grown on racks in plastic pots with a 0.7 l peat mixture in accordance with the generally accepted cultivation technology. In winter – with additional illumination, in spring – without artificial illumination.Results. From year to year, almost the same selection samples of cucumber had plants with the opposite arrangement of the first real leaves. These samples differed significantly in the number of plants with an unconventional arrangement of the first true leaves, but there were differences, sometimes very strong, between families of the same origin. All this suggests that the trait is genetically determined. When sowing cucumber seeds for seedlings on January 10-13, depending on the year of research and the genotype of the material used, from 18.3 to 25.6% of samples were identified that had plants with the opposite arrangement of the first and second true leaves. In seedlings for a spring heated greenhouse (sowing on March 15), there were about 15% of such samples, and 11.0% for non-heated ones (sowing on May 5). In general, the total number of plants with the opposite arrangement of real leaves in the first node was small and varied, depending on the growing conditions and the genotype of the studied samples, from 4.2 to 11.5% of the total number of studied plants. When sowing cucumber seeds at the same time, in the winter of 2019, compared to 2020 and 2021, there were 2.4 and 1.5 times more plants with the opposite arrangement of the first two real leaves. This can be explained by the fact that when planting seedlings, families with a large number of plants with opposite leaves were rejected. Weakened plants with opposite leaves within the family were also rejected. As a result, the material involved in further work had fewer plants with an unconventional arrangement of the first true leaves. It should be noted that plants with opposite leaf arrangement had only those F1 hybrids whose parent forms also differed in this disadvantage. It can be concluded that by selecting parent forms that do not have opposite leaf arrangement, it is possible to create hybrids that will not react sharply to the deterioration of growing conditions by laying opposite leaves.