The article provides the results of the analysis of methods and instrument equipment for the assessment of quality parameters of retted flax straw and flax fiber. The traditional methods and equipment are presented. The devices developed for flax fiber quality testing used in the Russian Federation, the Republic of Belarus and Ukraine are described. Methods, equipment and modern technologies used to determine the quality of flax fiber in European countries, Canada and the United States are provided. The role of modern developments to improve the efficiency of flax production is noted. Promising methods and devices for determining the main quality indicators are identified. The use of the method of automated forecasting of technological value of fiber flax stalks makes it possible to conduct a comprehensive quality assessment based on morphological and anatomical analysis. Modern capabilities of electronic scanning microscopy provide the control of the chemical composition and structural elements of flax stems at various stages of growth and development, as well as during maceration. The use of infrared spectrometry provides high accuracy in determining humidity, strength, fiber content, and long fiber yield.
However, along with high-precision equipment, there is the need for equipment and devices that allow determining the main technological indicators in the field with minimal labor, time and money costs. Research in this direction was previously carried out at the All-Russian Scientific Research Institute of Bast Crops Processing and in Kostroma State Technological University. However, the developments of the scientists were not tested in the production process and were not mass-produced. High speed and objective measurement methods will provide the accurate indicators during the process of maceration and primary processing of retted straw that will increase the technological value and competitiveness of flax fiber.

During the research, there were studied 186 varieties of spring soft wheat of different ecological and geographical origin to develop valuable initial material for new varieties in the conditions of Middle Volga. The studies were carried out in accordance with the methodic recommendations of VIR. According to the duration of the growing season, the samples were divided into three groups: early ripening – 29.4 %, mid-ripening – 45.0 % and mid-late-ripening – 25.6 %. The largest number of high-yielding varieties belongs to the mid-ripening group. Five groups are distinguished according to plant height: above 120 cm – tall, 120-105 cm – medium-grown, 104-85 cm – undersized, 84-60 cm – semi-dwarfs, less than 60 cm – dwarfs. A group of semi-dwarfs showed high resistance to lodging. The yield of productive genotypes in this group is 192-210 g/m². The analysis of the elements of the yield structure showed the varieties that exceeded the standard in the number of grains in the ear (32.8 pcs.): Annet (38.2 pcs.), Baganskaya 95 (36.5 pcs.), Riks (37.7 pcs.), Lubninka (36.8 pcs.), (Russia, West Siberian Region), Biryusa (37.2 pcs.) (Russia, East Siberian Region), by grain weight per ear – Russian varieties from East Siberian, West Siberian and Lower Volga Regions (0.96-1.52 g), and varieties of foreign selection from North America (0.89-1.64 г). According to the yield the following varieties significantly exceeded the standard variety Kinelskaya Niva (310 g/m²) by 30-54 g/m² (LSD₀₅ = 22.5 g/m²): Russian varieties Annet, Baganskaya 95, Lavrusha, Tarskaya 10, Pamyati Maistrenko, Omskaya 39, Duet (West Siberian region), Voevoda (Lower Volga region) and Uyarochka (East Siberian region), foreign varieties Aktyube 10 (Kazakhstan) and Granit (Canada). The varieties with complex resistance to the main types of leaf diseases (leaf rust and powdery mildew) have been identified: Norwell, Granit, Dandy, CDC Merlin (Kanada), Lavrusha, Tarskaya 10 (West Siberian Region), Tybalt (Netherlands), Voevoda (Lower Volga Region), Etyud (Ukraine). The identified varieties were used as parental forms in crosses.

The aim of the research is to make a comprehensive assessment of the new spring barley variety Tolkan of fodder grain use according to the economically valuable traits. Studies were carried out in 2016-2019. By the method of intraspecific hybridization of geographically distant forms and direction individual selection from the hybrid population of Pamos x Bankuti Korai, the new spring barley variety Tolkan has been developed. The variety is highly productive, of mid-ripening type, the growing season is 85 days, the average yield over the years of research was 5.4 t/ha, which exceeds the Biom standard variety by 0.8 t/ha (LSD₀₅ = 0.15), the maximum yield is 7.7 t/ha. The main element of productivity is the mass of grain per head 0.97 g, which has a close reliable relationship with the yield, r = 0.96 (reliability threshold at the level of 5 %, R = 0.88), the variety is mostly adapted to environmental conditions, Cv = 30.2 % (Biom standard variety − 36.7 %). It is characterized by large grain, the average absolute grain mass forthe years of research is 51.0 g, maximum - 63.0 g, by high resistance to lodging at a plant height of 57 to 94 cm, by immunity to loose smut and barley smut (absence of damage on an infectious background). When studying the variety in the production test of 2018-2019 according to the bare fallow predecessor, the yield for the first sowing period (May 7-11) was 4.14 t/ha, for the Biom standard variety − 3.27 t/ha (LSD₀₅ = 0.46), forthe second period (May 13-19) − 3.64 t/ha, for the standard variety − 2.4 t/ha (LSD₀₅ = 0.39 t/ha). On the basis of the comprehensive assessment Tolkan spring barley variety was transferred to the state test in 2019.

The article presents the results of a long-term study (2014-2018) of the biological characteristics of growth and development of plants of the introduced species – red feather clover (Trifolium rubens L.) when growing grass stands for seeds in the soil-and-climatic conditions of the Volga-Vyatka region. The species was assessed for winter hardiness, the duration of the growing season, plant height, structure of seed grass stand, seed productivity and seed quality. Winter hardiness of red feather clover in all years of cultivation was high (more than 80 %). The development of plants took place according to the mid-season type: depending on the conditions of the year of growth, they reached the flowering phase for 61-75 days; ripening phase – for 82-105 days from the beginning of regrowth. The duration of grass stand flowering was 14-40 days, ripening – 15-39 days. During the phases of development, the species is responsive to changes in the meteorological conditions of the year of study. In the first and second years of life, the active formation of the root system of plants took place, therefore, taking into account the structure of the seed grass, the height of the plants, the density of the stalk and the proportion of generative stems in the grass, the number of heads and the weight of seeds per 1 m² was lower than in subsequent years. Productive in seeds grass stand was formed since the third year of life and reached a plant height in the flowering phase of 49.2-56.2 cm, in the ripening phase – 50.4-63.4 cm. It was characterized by the density of the stems standing of 1019.7-1151.6 pcs/m² with the proportion of generative stems – 96.0-99.6 %, the number of mature heads – 978.9-1147.0 pcs/m2 and seed productivity – 18.8-55.0 g/m². Seed production was regular, despite strong fluctuations in yield. The seed material was of high quality: seed germination – 94-100 %, germination energy – 58.3-81.3 %, and was characterized by 1000-seed mass of 2.25-2.38 g, hard seed content – 9.1-20.0 %.

Ecologization of agricultural production and at the same time increasing of its efficiency is possible through the use of bacterial preparations. In long-term field experiments of 2016-2019 valuable characters of plant-microbial populations of red fescue (Festuca rubra L) variety Severnaya 82 of lawn and pasture use were studied after re-inoculation of seeds, obtained from the parent populations, which were also developed after inoculation with rhizosphere microorganisms on the basis of preparations of Mobiline 880, Azorizin 8, Azorizin 6, Flavobacterin, Agrofil and Rizoagrin. In the sowing experiment of 2016, plants of the first year of growth from the population with Mobilin 880 significantly exceeded in height (82 cm) the control plants without seed inoculation (77 cm, LSD₀₅ = 3.5). In the experiment of 2017, the plants of all created plant-microbial populations of the second year of growth exceeded in height (48-50 см) the control variant plants (45 cm, LSD₀₅ = 2.3). According to the yield of green mass in the 2016 experiment, populations of red fescue with Mobilin 880 and Rhizoagrin were distinguished (by 1.1 t/ha with yield in the control of 0.80 t/ha, LSD₀₅ =0.23). The prolongation of the effect of Flavobacteria in the experiment has not been observed. Plant-microbial populations with Azorizin 8 and Mobilin 808 proved to be promision according to the character of high seed yield: in the third generation, they had higher seed productivity (0.144 и 0.152 t/ha, respectively) compared to the control without inoculation (0.076 t/ha, LSD05 = 0.064). To create highly productive plant-microbial populations of red fescue seeds, it is necessary to search among highly productive parent populations inoculated with associative symbionts, followed by inoculation of daughter populations with the same bacterial preparations.

The research was carried out in 2017-2019 in the conditions of the Smolensk region on sod-podzolic medium loamy slightly acidic soil. The study included 25 varieties and lines of fiber flax of domestic and foreign selection. The mid-ripening variety Impuls (Russia) was used as a standard, whose yield, depending on the test year, was 1.07...1.29 t/ha. As shown by the calculations of the index of environmental conditions, the most favorable conditions for fiber flax developed in 2018 (I_j = +0.46), and stress conditions, caused by excessive moisture during the critical period of plant growth and development (GTC = 1.7), in 2017 (I_j = -0.55). On average, over the years of research, the yield of fiber, depending on the genotype, varied in the range of 1.00...1.97 t/ha. The highest yield on average for three years of testing (1.78...1.97 t/ha) and average yield in contrasting conditions were characteristic of the varieties Cesar, Sinel, Dobrinya (Russia), Marylin (Holland), Andrea, Altea (France). Under favorable weather conditions (2018), a high potential for the yield of flax fiber compared to the average value (121.5...133.3 %) was obtained in the varieties Cesar, Dobrinya, Sinel (Russia), Belita (Belarus), Andrea, Altea (France), Marylin (Holland). Under stressful conditions (2017), high adaptability was found in the samples of the Russian selection Cesar (173.4 %), Sinel (168.0 %), Dobrinya (151.1 %), Tost 3 (128.7 %), Alfa, Universal (127.7 %). The varieties Surskiy (bi = 2.2), Belita (Belarus), l. 323-02 (Russia), Marylin (Holland) − 1.7, Alexandrit (Russia), Andrea (France) – 1.5. Were characterized by high responsiveness to cultivation conditions (b_i> 1). Russian varieties with a relatively stable yield: Cesar, Sinel – 0.7, Alpha – 0.6, Lider, Smolich, Tost 3, Universal – 0.5, Impuls – 0,2 did not show reaction to changes in growing conditions (b_i <1). Thus, the domestic varieties Cesar, Dobrinya and Sinel have the highest yield of flax fiber and adaptability to the soil and climatic conditions of the Central Non–Black Earth Region. Expansion of fiber flax acreage under these varieties will provide strengthening of the domestic raw material base.

The article presents the results of study of potato varieties and hybrids collection in the conditions of Kirov region, including varieties of modern Russian and foreign collections, interspecific hybrids of VIR, Falenskaya selection station and other scientific institutions for 300-350 samples annually. The study was conducted in contrasting weather conditions in 2017-2019. Sources of high productivity (705…887 g/bush): 129-10, Effekt (Russia), Lukawa (Czechoslovakia), Zorachka, Uladar (Belarus), Colomba (Netherlands) and others, and large potato tuber (100…140 g): Bellarosa (Germany), Lilea (Belarus), Irbitsky, Krepysh (Russia) were revealed. Due to big epiphytotic of late blight in 2017 varieties with high field resistance of foliage to late blight were revealed (7-9 points): Kufri Anara (India), Suzorye, Ragneda, Alpinist (Belarus), Gubernator, Skazka, Effekt, Vdohnovenie, Fritella, Legenda, 90-5-30, 55-03 (Russia); 387110.4, 678019 (Peru) and others. In 2019 samples with high late blight resistance of tubers were selected (9 points): Lilea (Belarus), Udacha, Ognivo, Lubava Legenda, 122-29, 90-6-2, 194-00, 591-97, 55-03, 56-09, 172-11, 6-1, 39-10, 132-07 (Russia), 389746.2, 678019 (BL-22), 678009 (BL-1.10) (Peru). Varieties of field resistance to viral diseases were selected: Lukawa (Czechoslovakia), Yanka, Ragneda, Zorachka, Charaunik (Belarus), Franzi, Albina, Kolomba, Sofia (Germany), Lazar, Skazka, Mayak, Udacha, Krasavchik, Charodey), Zolsky, Matushka, Nayada, Sudarynya, Kolobok, 42-7-40, 112-04, 184-05, 28-06, 48-224-10, 455-08, 431-08, 142-09, 5-7К, 1-13К, 218-12, 286-08, 40-14К, 16-25-1К, 16-29-33К, 56-09, 289-13. Assessment of starch content allowed to select varieties and hybrids with starch content above 20%: Bashkirsky, Zolsky, Lazar (Russia), Uladar, Vektar Belorussky, Manifest, Zhuravinka, Zdabytok (Belarus) and others. Hybrids 268-09 and 289-13 combined high starch content and high late blight resistance. The most valuable source material for potato breeding in the Kirov region are varieties and hybrids with a complex manifestation of warnings: Bellarosa, Albina, Sofia (Germany), 129-09, 40-14, 7-2В, 5-7 К, 268-08, 141-14, 289-13, 455-08, 56-09, 149-14, Kamensky, Irbitsky, Debryansk, Effekt (Russia), Kolamba (Netherlands), Zorachka, Сharaunik, Uladar, Altair, Lilea (Belarus), Lukawa (Czechoslovakia).

One of the directions of apple breeding in the Middle Urals is the development of varieties with a long-term storability. The ability of apples to maintain their consumer qualities for a long period is one of the most important indicators of the variety. A significant role in the storage of apples is played by the amount of ethylene produced in them. The paper presents the results of identification of genes involved in the control of ethylene biosynthesis in apple varieties selected by the Sverdlovsk horticultural breeding station. A total of 21 apple varieties were analyzed. The main objective of the study was to detect Md-ACO1-1 and Md-ACS1-2 alleles in the homozygous state. The combination of these alleles in one genotype reduces the production of ethylene in fruits, which contributes to their long-term storability. The analysis showed the availability of polymorphism in the two studied genes. The Md-ACO1 gene is characterized by the availability of two alleles in most varieties. The homozygous Md-ACO1-1 allele was identified in the Isetskoe pozdnee variety. Analysis of the Md-ACS1 gene revealed the predominance of the Md-ACS1-1 allele form. The Md-ACS1-2 allelic form was observed only in heterozygous samples. No combination of Md-ACO1-1 and Md-ACS1-2 alleles was found in the homozygous state. However, heterozygous forms are also of interest for breeding. They can serve as a source of a character of reduced ethylene biosynthesis when creating varieties with a long-term storability. Such varieties are Sokol yasnyy, Aksena, Rozovatoe zimnee, Sverdlovchanin, Isetskoe pozdnee, Blagaya vest'. The comparison of fruit storage periods and the genotype of the variety has been made. Allelesassociated with a reduced level of ethylene biosynthesis are typical both for the varieties with low and high storability.

The research is devoted to the development of clonal micro-propagation technology of the decorative cereal Molinia caerulea (L.) Moench. The concentration of 2.0 mg /l of cytokinin 6-benzylaminopurine (6-BAP) contributed to obtaining the maximum number of microshoots: 6.3 and 7.9 pcs. on Anderson's and Murashige-Skoog's (MS) media, respectively, which exceeded the control (by 4.7 and 6.3, respectively, with LSD₀₅ = 2.3). The length shoots were observed on hormone-free media, this indicator significantly decreased with an increase in 6-BAP content. On Anderson and MS media with 1.0 mg/l 6-BAP, the shoot length averaged 21.5 and 26.4 mm, respectively, which made it possible to transplant them for rooting, bypassing planting on a medium for elongation. The inclusion of the Siliplant micro-fertilizer in the MS medium at doses of 1.0 and 2.0 ml/l contributed to a significant increase in shoot size, by 16.7 and 10.7 mm (LSD₀₅ = 8.9), respectively, in comparison with the control (MS). It is recommended to use Anderson's medium and 0.5 mg/l of indole-3-acetic acid as a medium for rhizogenesis: after two weeks of cultivation, the regenerants had a standard appearance with developed roots suitable for planting for adaptation. At the adaptation stage, watering the substrate with the biofungicide «Trichoderma veride» according to the instructions and a cereals single spraying with the micro-fertilizer «Siliplant» at a dose of 1.5 ml/l contributed to their 100 % survival rate.

The article presents the results of studies of complex effect of biopreparations use during basic and pre-sowing soil tillage on root rot damage and leaf and stem infections of spring grain crops (wheat cv. Svecha, barley cv. Lel’, oats cv. Selma). Studies of 2010-2017 were carried out in seven-field crop rotation on sod-podzolic medium-loam soil. The root rot damage of spring wheat was significantly lower (17.9 %) by surface tillage than by ploughing (22.5 %) in arid conditions with insufficient productive moisture (9.1-17.2 mm) and an increase in soil density (1.37-1.43 g/cm³). Under optimal humidification conditions, the differences in root rot damage of barley are equaled (21.3 and 22.4 %). High soil density (1.32-1.36 g/cm³) also caused an increase in the number of diseased oat plants by surface tillage (21.6) compared to ploughing (14.6 %). Treatment of crops with the preparations Streptomyces castelarensis А4 and Pseudobacterin-2 in the tillering phase led to a significant decrease in root rot damage only on oats (by 17.1 and 17.4 %, respectively). The degree of damage of spring grain crops with leaf and stem diseases was not significantly affected by the methods of basic and pre-sowing tillage. Only the use of a combined sowing unit for cultivation of spring wheat reduced the damage with leaf rust by 2.9 %, with septoriosis – by 1.0% compared to the control. On wheat, the preparations were effective on the background of ploughing reducing leaf rust damage by 15.2 and 11.6 %. The preparation S. castelarensis А4 had a greater effect on barley: the number of plants affected by crown rust was 19.1% less. Pseudobacterin-2 had a better effect on the background of surface tillage, reducing the incidence by 12.9 % relative to the control (ploughing to 20-22 cm). On oat sowings, the preparations were comparable in effect: the intensity of crown rust damage was significantly lower by 5.0 and 4.7 % compared to the control. The action of S. castelarensis А4 is more effective on the background of surface soil tillage. Pseudobacterin-2 had the best effect by plowing. The damage of wheat with stem rust and septoriosis was low. Thus, the methods of basic tillage did not affect the damage of grain crops with leaf and stem diseases and significantly decreased the development of root rot in wheat and oats. Methods of pre-sowing tillage did not have a significant effect on the damage of spring grain crops with root rot and significantly reduced the damage of wheat with leaf rust and septoriosis. The preparations used reduced the intensity and the development of root rot of oats and leaf and stem diseases of wheat, barley, oats.

The article informs on the 2006-2019 studies of the effect of resource-saving methods of tillage based on the use of combined tillage units KOS-3 (1st minimum), BDM-3.2х4 (2nd minimum), Spider-6 (3rd minimum without autumn tillage) in two crop rotations (grain-fallow-row crop rotation and grain-fallow-row green manure crop rotation) on the structural-aggregate composition of gray forest soil and crop yields. During the year of laying the experiment the percentage of structural aggregates (0.25-10 mm) in the soil of a grain-fallow-row crop rotation ranged from 72.2 to 74.4 %, in a grain-fallow-row green manure crop rotation – from 70.1 to 73.2 %, with the structural coefficient (K) 2.60-2.91 and 2.41-2.73, respectively. For two crop rotations the structural state of the soil improved due to the effect of green manure crop rotation (К = 3.07, LSD₀₅ = 0.13) as compared to the grain-row without green manure (К = 2.93). More significant differences according to the soil structure coefficient were obtained in studied tillages: 3.03 (plowing), 3.41 (1st minimum), 2.91 (2nd minimum), 2.65 (3d minimum) with LSD₀₅ = 0.17. The first and the second methods of minimal tillage had an advantage over plowing as to the increase in agronomically valuable aggregates (0.25-10 mm) as compared with the original soil. On the average among the crop rotations the yield of grain crops by classical and 1st minimum methods of tillage (3.65-3.66 t/ha) exceeded significantly the indicators of all the rest variants with minimum tillage (by 0.15-0.43 t/ha, LSD₀₅ = 0.10). The yield of potato in all variants with minimal soil tillage was significantly lower (by 5.1-8.3 t/ha, LSD₀₅ = 1.44) than with plowing (27.8 t/ha). The assessment of profitability of grain crops cultivation showed the advantages of replacing the moldboard plowing for resource-saving methods using combined tillage units KOS-3 and BDM-4-3.2 which provided the yield of spring and winter wheat, barley and spring vetch at the level of 2.42-4.50 and 2.33-4.41 t/ha, respectively, with cultivation profitability of 51-64 and 44-59 %. The third minimum method of tillage decreased the cultivation profitability of grain crops and vetch by 10-15 %. The best indicators of potato production profitability (67-82 %) were achieved when using the classical variant of soil tillage.

The studies were carried out in the southern part of the Rostov region in 2017-2019 on typical carbonate chernozem. Studied was the efficiency of periods of ammonium nitrate application (N₃₀, N₃₀₊₃₀ ) in autumn when the vegetation season is finished, in spring in the thawed soil, and during the tillering phaseon the yield and quality of winter wheat grain of Krasa Dona variety by different seed sowing rates (500, 600, 700 pcs/m²). Soft winter wheat variety Krasa Donacultivated after sunflower has shown a good reaction to double nitrogen top-dressing in autumn and in spring (N30 in autumn when the autumn growing season is finished + N₃₀ in spring on thawed soil). In this variant there has been formed the largest yield of 6.09-6.18 t/ha. The productivity excess over the control variant (without nitrogen top-dressings) was 2.38-2.63 t/ha, depending on the seeding rate, which significantly exceeded the level of LSD₀₅ in the experiment (LSD₀₅ = 0.24 t/ha). In addition, in this variant with the seeding rate of 500 pcs/m² the maximum economic efficiency was obtained. The profitability was 121.3 %, and the contingent net income was 34,268 rub/ha. The application of nitrogen fertilizing provided an increase in the mass of 1000 grains to 42.6-43.0 g (39.8-40.2 g in the control) and increased the gluten content in the grain to 20.5-21.8 % (18.6-18.8 % in the control).

It is known that significant saving of nitrogen fertilizers are due to perennial legume-cereal grasses use in crop rotations. From 2013 to 2018in the Mari El Republic six-field grass-grain fodder crop rotations were compared on sod-podzolic soils with a very high level of phosphorus and potassium. In the third rotation their productivity and bioenergetic efficiency, changes in several important soil fertility indicators, and crud protein content in the produced fodder were evaluated. The main difference between the crop rotations was based on the duration of the clover-alfalfa-timothy grass mixture (CAG) use: from one year to three years. In given experiment there was also studied the effect of mineral nitrogen (variants N₀, N₆₀) against Р₆₀К₆₀ background on the yield of crop rotations. During six years, there was no significant soil acidification in the variants. Each additional year of clover-alfalfa-timothy grass mixture use raised the energy efficiency ratio of crop rotations by 24-47 % (from 1.13-1.24 by one-year use to 2.08-2.25 by three years of use). Three-year CAG use as compared with one- and two-years has given to the crop rotation significant advantages in energy efficiency (up to two times) and productivity (approximately 40-80 %) of cultivated crops. After refusing to apply nitrogen fertilizations in such crop rotation, average crop productivity, soil humus and nitrogen content in the soil were better preserved. The average crude protein content in dry matter of the obtained fodder increased from 12.7 % to 14.6 % when prolonging theca use up to two years. The average energy value of the yield per rotation was recorded low (8.4-8.7 MJ/kg) and did not depend on the studied factors.

The article presents the results of scientific research for 2014-2019 on the reaction of early-maturing fiber flax varieties (Linum usitatissimum L.) of the Pskov selection Peresvet, Kvartet, Voskhod and Dobrynya to growing conditions: sowing time, seeding rates (16, 18, 20, 22, 24 million pieces of germinating seeds per 1 ha), doses of nitrogen fertilizers (0, 15, 30, 45 kg of active ingredient (a. i.) per hectare. The hydrothermal coefficient (GTC) for the growing season varied from 0.98 to 1.94. The optimal seeding rate for fiber flax of the Peresvet variety is 22 million pcs /ha, and for the Kvartet variety − 20 million pcs /ha. With these seeding rates the yield of flax fiber was 21.9-20.6 hundred kilograms (centners) per hectare, respectively, that significantly exceeded the yield of fiber with the minimum seeding rate of 1,0-1.7 hkg/ha, respectively, with LSD₀₅ = 0.7-0.9 hkg/ha. The maximum yield of seeds in both varieties was obtained at the minimum seeding rate. The optimal sowing period for the Peresvet variety was the third period (May 8-17th, 2014-2016) and the second period for the Kvartet variety (May 11-20th, 2017-2019). The yield of flax fiber for these varieties significantly exceeded the 1stsowing period by 0.7-2.3 hkg/ha, respectively (LSD₀₅ = 0.6-0.8 hkg/ha ) and amounted to 23.0-21.1 hkg/ha , that of seeds – 9.8-9.1 hkg/ha. The optimal nitrogen doses for R₄₀K₆₀ background are for Voskhod and Kvartet varieties 15 kg a. i./ha, and for the Dobrynya and Peresvet varieties − 30 kg a. i./ha. The yield of flax fiber for them exceeded the control by 1.5-1.3 hkg/ha, respectively (LSD₀₅ = 0.6-0.8 hkg/ha) and 2.7-2.5 hkg/ha (LSD₀₅ = 1,0-0.9 hkg/ha). The payback of 1 kg of nitrogen by flax fiber increase in all varieties was the highest with the minimum dose of N₁₅. Among the varieties, it ranged from 8 to 12.7 kg/kg. The specific removal of food elements per 1 ton of flax straw and flax fiber recommended for use in determining the doses of mineral fertilizers for the planned yield of flax fiber, has been determined.

In the conditions of the Chuvash Republic, the effect of slottingbetween rowson hop yield and on the water-physical properties of gray forest soil was studied. Soil slotting was used during 2017-2019 in autumn after the completion of harvesting operations (late September-early October) on hop plantations of the Podvyazny variety. Tillage with a SCHX-1.6slotting device (Czech Republic) was carried out to the depth of 50 and 65 cm at different time intervals (annually and three years later). As the control, there was taken the conventional tillage without the use of aparaplow combined with autumn tillage of row spacing to a depth of 20 cm. Studies have shown that the use of aparaplow to a depth of 50 and 65 cm improved the aeration and water permeability of the soil (the specific weight of the 20-25 cm soil layer decreased by 0.1-0.2 g/cm³, the volume weight of the same layer-by 0.1-0.3 g/cm³) and contributed to an increase in hop yield by 1.4-3.1centners per hectare (LSD₀₅ =1.3 centners/ha) compared to the conventional tillage of row spacing (20.9 centners/ha). The content of alpha-acids in hop cones was not affected by slotting between the rows of hops. The specific weight of the 50-55 cm soil layer significantly decreased in all variants in comparison with the control. The highest moisture content of the deep layers of the soil (30-55 cm) was achieved with conventional tillage combined with annual autumn slotting to 50 cm depth. All the studied variants in comparison with the control give a significant increase in the yield of hop cones. For the production, the variant with the lowest costs for deep tillage should be recommended. It is the annual processing of the top soil layer combined with the autumn slotting every 3 years to 50 cm depth.

The qualitative peculiarity of the existing land market in rural areas requires constant assessment of both the mechanisms that control its development and the direction of changes in its segments. Therefore, the purpose of the study was to analyze the territorial features of the development of the agricultural land market in modern conditions of the implementation of the import substitution policy. The research was carried out across the constituent entities of the Russian Federation of the Northwestern Federal District (NWFD) and in more detail on the example of the municipal districts of the Leningrad region using data from Rosstat, Rosreestr, the Ministry of Agriculture of the Russian Federation and other sources. Statistical methods of information processing were used. Based on the analysis of the dynamics of changes in the size of the cultivated areas, it was concluded that there were unfavorable tendencies as to the demand for arable land in the conditions of the Northwestern Federal District. Due to it, the reduction in the area under crops occurs in regions with more favorable conditions for agricultural activities. As the result, the growth in the number of transactions for the sale and purchase of agricultural land in the regions of the Northwestern Federal District is not sustainable. On the example of the municipal districts of the Leningrad region, the features of the primary and secondary market for agricultural land were revealed: the supply of land plots exceeds demand and is localized in the suburban area, such types of land turnover as the purchase and sale and lease of land plots have limited development. Depending on the location and other rental characteristics, the level of land prices, even within the boundaries of one municipal district, varies from 2.5 to 15 times. It has been established that the development of subsystems of market turnover of agricultural land is closely related to the conditions and results of economic activity in rural areas.