Light Loamy Soil Research Articles

Effect of fertilizers and meliorants on the value of soil acidity of sod-podzolic light loamy soil, yield and chemical composition of the green mass of spring rapeseed (according to laboratory and vegetation experience)

Under controlled conditions of laboratory vegetation experience based on very strongly acidic sod-podzolic sandy loam soil, a comparative study of the fertilizing value and reclamation properties of complex mineral fertilizers (azofoska andAPAVIVA) and meliorants of a carbonate nature was carried out: conversion chalk (CC), gravel screening (GS), dolomite (DM) and dolomitized (DIM) limestone flour, as well as silicate nature–blast furnace slag (BFS) and hydroxide nature–Mg(OH)2.Culture–spring rape of theLexus variety.It was shown that the reclamation effect obtained as a result of the use ofBFSand meliorants of a carbonate nature differed little from each other and after 45 days of plant cultivation were insignificant.Magnesium hydroxide did not have a reclamation effect.The yield data of the vegetative mass of rapeseed after harvesting are given.It is shown that the chemical composition of meliorants had a significant effect on the formation of the elemental composition of plants.

Effectiveness and Duration of Action of Dolomite Screening Particles Used for Reclamation of Acidic Soils. Empirical Models of the Acidification Process of SodPodzolic Light Loamy Soil (according to Field Experience)

In a long-term 10-variant microfield experiment based on a mediumacidic sod-podzolic light loamy soil, a comparative study of the reclamation properties of the screening of dolomite crumbs stored in dumps, without separation into fractions (SIF), particles of 5–7 and 7–10 mm in size and dolomite flour (DF) prepared from the screening of dolomite when sifting dolomite crumbs with the diameter of the holes is 0/25 mm. The experiment lasts for 14 experimental years. It has been revealed that dolomite particles of 5–7 and 7–10 mm in size are valuable calcareous material. Their use leads to the neutralization of soil acidity already in the year of liming. The higher the dose of application, the greater the reclamation effect. There were no significant differences in the effect of granules of 5–7 and 7–10 mm in size, applied in equivalent doses, on the pH value. The positive effect of liming with meliorant in the amount of 3 and 5 doses of hydrolytic acidity (Ah) did not end after 14 experimental years after reclamation and allowed to postpone the period of repeated (maintenance) liming. The positive effect of using a natural mixture of chalk fractions (SIF) in a scientifically justified dose was inferior to dolomite flour. Clustering of individual variants of the experiment was carried out according to their effect on the рHKCl value for the entire period of the experiment. Linear trends of the averaged dependencies of the acidification process for meliorant particles of various sizes over the entire period of the experiment have been developed. The mechanisms of interaction of dolomite particles with soil in the process of land reclamation are considered.

Efficiency of nitrogen fertilizers and biological preparations for winter rye on soddy-podzolic soil of different cultivation status

There was studied the influence of soddy-podzolic light loamy soil of different cultivation status on the agronomic efficiency of mineral fertilizers application with varying doses of nitrogen and biological preparations applied against the mineral background, in Pskov region. On moderately cultivated soil the linear dependence of grain yield on nitrogen rates was established. An increase in nitrogen doses from 20 to 80 kg a. i./ha resulted in obtaining an additional yield compared to the control variant, which is dependent on soil pH: yield growth by 6% to 42% was recorded on soil with pH of 5.6; from 8% to 73% – on soil with pH of 5.3; from 32% to 69% – on soil with pH of 5.2; from 66% to 175% – on soil with pH of 4.8. Payback from applied fertilizers rose with increasing doses of nitrogen. Soil properties also influenced the payback value. The maximum payback, 12 kg of grain per 1 kg of NPK, was recorded when N80P40K70 with split nitrogen fertilizing was applied to the soil with pH = 4.8. The introduction of biological products to the variant with mineral fertilizers (N20P40K70 + N20) contributed to an increase in grain yield : the introduction of microbiological preparation Bisolbifitis provided additional 7.55%; spraying of foliar fertilizers – 3.67%–8.78%. On the soil with long-term cultivation status the dependence of yield on the doses of applied nitrogen in the range from 20 to 80 kg a. i./ha looked like a polynomial. Maximum yield was obtained in different years when nitrogen was applied at rates from 40 and 60 kg a. i./ha. An increase in the dose of nitrogen from 20 to 40 kg was accompanied in 2019 by an increase in the yield of grain from 11.2% to 22.6%. An increase in nitrogen rates from 20 to 60 kg in 2020 and 2021 resulted in the growth of grain yield from 20% to 65%. Respectively. When the most effective doses of nitrogen were applied the payback from fertilizers was 5 kg of grain per 1 kg of NPK in 2019; 7 kg of grain per 1 kg of NPK in 2020; and 10 kg of grain per 1 kg of NPK in 2021. On the soil cultivated and improved for a long-term the effect of foliar fertilizers with biological preparations Kodamine B-Mo and K-Humate-Na was less significant (3–3.5%).

Technological methods for increasing the yield and fertility reproduction when growing zucchini on sod-podzolic light loamy soil in natural and climatic conditions of Republic of Belarus

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.

Assessment of the influence of mineral fertilisers on the phosphate regime of meadow chernozem carbonate soil and yield of sunflower and winter wheat

The relevance of the study lies in the need to maintain optimal levels of mobile phosphorus in carbonate soils to support healthy plant growth and development, as it can be converted into less mobile forms in such soils. The purpose of the study was to assess the impact of various long-term fertilisation strategies on the content of various forms of phosphorus in the soil to improve this availability. The research was conducted in 2019-2022 as a stationary experiment in a separate division of the National University of Life and Environmental Sciences of Ukraine “Agronomic Experimental Station” in Kyiv Oblast on meadow chernozem carbonate low-humus coarse-sawn light loamy soil in a five-field crop rotation, where the influence of different levels of fertiliser saturation (no fertiliser, minimum, average, and optimal) on soil phosphate status and yield of Etana winter wheat variety and Sumiko sunflower hybrid was investigated. Soil samples were taken from the 0-20 and 20-40 cm layers, and the group and fractional composition of phosphates was determined using the Chang-Jackson method and the content of mobile phosphates using the Chirikov and Machigin methods. According to the analysis of the group and fractional composition of soil phosphates, it was found that in meadow chernozem carbonate low-humus coarse-sawn light loamy soil, the content of iron phosphates prevails among all fractions during long-term fertilisation. The results showed an increase in the content of aluminium phosphates in the 0-20 cm surface layer of the soil of two variants with long-term fertilisation, and an increase in the content of the second fraction of soluble calcium phosphates (Ca-PII), with the minimum saturation (N27P18K20) with the highest available phosphate fraction for plants (Ca-PI) is observed. The content of mobile phosphates was maximal at optimal fertiliser saturation (N81P54K62) and was 4.8 and 8.5 mg/100 g of soil, the aftereffect of organic fertilisers positively affected the accumulation of mobile phosphates in the soil. The highest yield of winter wheat (7.55 t/ha) and sunflower (4.28 t/ha) was obtained with optimal fertiliser saturation, the lowest – without the use of fertilisers, where it was 4.45 t/ha for winter wheat and 2.23 t/ha for sunflower. The results of the study can be used to develop more sustainable and effective strategies for using phosphorus in soils, which can help preserve soil resources and prevent possible contamination of water sources due to excessive phosphorus intake

Effect of coated urea and NPK-fertilizers on spring wheat yield and nitrogen use efficiency.

Among the factors that increase the efficiency of mineral fertilizers, due consideration has lately been given to the development and study of fertilizers with various granule coatings. This study is focused on the test of urea and NPK fertilizers, with granules coated with 50 and 100 μm monocalcium phosphate. Two-year greenhouse trials with spring wheat were carried out on soddy-podzolic light loamy soil. Coated fertilizers have proven to be more effective than traditional ones. For instance, using coated urea improved the yield 10-11% compared to conventional fertilizer. At the same time, the weight of one plant increased by 9-11% and the weight of the ear by 10%, the number of grains in the ear was by 4-7% bigger. Similar results were obtained with NPK fertilizer. Providing a thicker coating from 50 to 100 μm significantly increased the efficiency of both urea and NPK fertilizers.

Influence of agromelioration and drainage methods on the field crops productivity

The effectiveness of ameliorative strip loosening to a depth of 50-60 cm and volumetric soil slotting to 45-50 cm, their influence on the productivity of field crops and agrophysical properties of drained soils with different ameliorative systems (interdrainage distance of 18 and 28 m) was studied. The experiment was carried out in the period 2015-2021. at the Gubino agricultural polygon of the All-Russian Research Institute of Reclaimed Lands (Tver Region). The soil is soddy-podzolic cultivated light loamy gleyic, drained by closed pottery drainage, formed on a moraine. Volumetric slotting was carried out with a specially designed tool with filling the subarable part of the slot with crushed straw and plant residues mixed with a humus layer. Ameliorative loosening (MR) was carried out with a converted chisel plow. The pitch of slotting and MP is 140 cm. According to the generalized data, the best results on both drainage systems were obtained in the variant with volume slotting. Ameliorative loosening increased the yield of grain crops, on average over 5 years, by 0.60 t/ha (17.0%) and 0.79 t/ha (20.7%), slotting by 0.90 and 1.02 t/ha ha (25.6 and 26.7%), respectively. Additional grain harvest for the five-year period of MR action on the estimated drainage was 3.0, on sparse - 3.95 t/ha, and with volumetric slotting of the soil - 4.5 and 5.1 t/ha, respectively. On spring rapeseed, the best results were also obtained in the variant with sparse drainage and volumetric slotting of the soil. The increase in the yield of green mass in this variant, on average over 3 years, amounted to 3.6 t/ha of green mass, or 19.0%. It has been established that on soddy-podzolic light loamy gleyic soils with an atmospheric type of water supply, when designing ameliorative systems for field crop rotations, it is possible to use drainage systems with extended, compared to the calculated, interdrainage distances, which helps to reduce the cost of drainage. The use of land reclamation techniques increases the efficiency of sparse drainage.

Estimation of Carbon Stocks in Soils of Forest Ecosystems as a Basis for Monitoring Climatically Active Substances

The eluvozems and soddy eluvozems on two-layer deposits dominating in the soil cover of the Zvenigorod biostation of Moscow State University contain, on average, 65–83 t/ha of organic carbon in the litter and a meter-deep layer of mineral strata. Carbon stocks are minimal in the soddy eluvozem of the complex spruce forest (59–68 t/ha), which is characterized by a lighter granulometric composition, and reach 76–92 t/ha in the soils of the birch–spruce and complex pine–spruce forests. At the same time, 3.3–5.8 t C/ha or 4–9% of the total organic carbon reserves are concentrated in the litter, and 64–69% in the upper mineral layer (0–20 cm). Different levels and profile distribution of organic carbon reserves in soils are determined by lithological and granulometric features and the nature of vegetation. The contribution of water-extractable organic carbon compounds to their total content in the upper mineral horizons of soils does not exceed 1.3–1.8%, microbial carbon, 1.7–2.4%. In acidic light loamy soils, the enrichment in calcium and potassium, the cation exchange capacity, the content of exchangeable bases, and the degree of saturation can serve as indicators of the content and reserves of organic carbon at the ecosystem level. The relationship with the content of finely dispersed fractions and oxalate-extractable Al and Fe is manifested to a lesser extent due to the similar origin and properties of soils. The variability of organic carbon stocks in soils is determined to the greatest extent by its content, the influence of which decreases with depth. Accounting for spatial heterogeneity, field measurements of the density and proportion of fine earth, and correct analytical determinations are essential components of the assessment of carbon stocks in soils of forest ecosystems as part of a national monitoring system for carbon pools and greenhouse gas fluxes under development.

Acid-Base Buffering Assessment and Directions of Silicon Compound Transformation in Sod-Podzolic Soil when Used Various Siliceous Rocks

The variability of the main indicators of acid-base buffering of sod-podzolic light-loamy soil was investigated, and the dynamics of the content of monomers and polymers of silicic acid and acid-soluble silica compounds in the soil under conditions of reclamation doses of various siliceous rocks (diatomite, zeolite and bentonite clay 3, 6, 12 t/ha) was described. Zeolite rock and bentonite had a positive effect on the anti-acid buffering ability of the soil, shifting the H+/OH–equilibrium of the system by more than 160 and 20, respectively, depending on the applied dose of the material. The effect of diatomite was manifested in the anti-alkaline region of soil buffering, due to which the H+/OH–-equilibrium index decreased by almost 40%. Against the background of the use of diatom rock and bentonite clay, the content of silicic acid monomers in the soil increased by more than 5 and 4 times, respectively, against the background of the use of zeolite – by more than 2 times. The content of silicic acid polymers in the soil increased up to 3 and 4 times with the use of zeolite and bentonite rocks, respectively. At the same time, the introduction of diatomite into the soil contributed to an increase in the content of H4SiO4 polymers by 5–10 times, depending on the dose of the material. The content of the acid-soluble fraction of silicon compounds in the soil increased by 1.4–2.8 times against the background of different doses of the studied rocks and, in general, had a different dependence depending on the composition of each of them. Based on the revealed irregularities in the content and dynamics of mobile silicon compounds in the soil (monomers and polymers of silicic acids, acid-soluble silica fractions), the characteristic is given and the value of the first proposed indicators describing their dynamic state and directions of transformation – the potential for the formation of monomers (M-ASi) and polymers (P–ASi) is disclosed. H4SiO4, the degree of polymerization (Pm-VSi) and depolymerization (Dm-VSi) of silicic acid, the total content of the loose-amorphous silica fraction (Si-AMF) and the degree of amorphousness of the Si-containing mineral phase of the soil (AMF-VSi). The study of the influence of silicon materials in conditions of sod-podzolic soil revealed that, depending on the qualitative composition and dose of silicon rock, the M-ASi index can increase by 30–80%, and the P-ASi index can be in the range of increase from 0.3 to 3.0 or more times. The processes of polymerization of silicic acid and the decomposition of its polymers into monomers, expressed respectively by Pm-VSi and Dm-VSi, can also actively increase against the background of the interaction of soil with rocks, the measure of change of which is expressed in the order of 10–40% deviation relative to the control. The total content of loose-amorphous silica fraction in the soil, expressed by the SiAMF index, can be determined by the composition of each siliceous rock used as a meliorant. If, when using diatomite, the indicator can decrease by almost 30%, then when using zeolite and bentonite clay, it can increase by 30–100%, depending on the dose. Similarly, the indicator of the degree of amorphousness of the silicon-containing part of the soil substance (AMF-VSi) can also change.

Физико-химическая оценка почвы в технологии выращивания озимого тритикале

In the experiment, it was found that the productivity indicators of the aboveground mass of winter triticale of the Tribune variety and the content of nitrogen, phosphorus and potassium in their plant tissues are generally consistent with water-physical, physico-chemical parameters and with soil bonification data. It was found that there were no differences in the mass of green leaves and the dry mass of the aboveground part of triticale on chernozem typical of agrocenosis and virgin soil. Of the forest soils, the smallest mass of triticale leaves was obtained on gray forest and turf alluvial, and the largest on sod–podzolic light loamy soil. Plants with massive leaves were also obtained on alluvial meadow soil of the same light loamy granulometric composition. The water content of triticale leaves, as a rule, does not depend on soil fertility. Only on the chernozem-meadow soil of the trunk strips of the apple orchard, in contrast to the row-to-row soil, the hydration of the leaves turned out to be significantly higher. This can be explained by a less acidic reaction, greater hygroscopicity and nitrogen content in the soil of the trunk strip. In summary, winter triticale plants are recommended to be used as a test crop when assessing the degree of soil cultivation. Keywords: WINTER TRITICALE, DEGREE OF CULTIVATION, BIOINDICATION, APPLE ORCHARD, NATURAL LANDS

Changes in the Microbiological and Physico-Chemical Properties of Soils after Fires in Pine and Birch Forests of Central Regions of the Zabaikal Krai

The microbiological and some physico-chemical properties of illuvial-ferruginous soddy-podburs (Entic Rustic Podzols) soils in Scots pine forests and gray-humic typical light loamy soils (Umbrisols) in secondary birch forests of the central regions of the Zabaikal krai have been studied. Fires in soddy-podburs pine forests resulted in decrease in the total exchangeable basis, total nitrogen, mobile forms of potassium and phosphorus, and in increase in the proportion of C : N; while in birch forests, on the contrary, an increase of the mentioned indicators and a narrowing of the C : N proportion in the gray-humic typical soils were observed. The content of humus in the upper soil horizon decreases only in recently burned Scots pine forests after a high-severity fire, while in other sites it increases. A decrease in the soil acidity was observed at all burned sites. High-severity fires lead to a significant decrease in the content of microbial biomass and the intensity of basal respiration, as well as to a change in the structure of ecological and trophic groups of microorganisms in the soils up to a depth of 10 cm of the mineral horizon, while low-severity fires mainly affect the duff. The qCO2 coefficient increased 2–5 times after fires in the duff and 1.5–2 times in the humus horizon only after high-severity fires. In recently burned Scots pine forests, the storage of microbial biomass and microbial production of carbon dioxide significantly decreased up to a depth of 10 cm of the mineral soil layer. In the steppe site formed after the impact of fires in the pine forest, and in the birch forest after a high-severity fire, in the humus horizon the carbon storage of microbial biomass decreased by 15–20%, and the microbial production of CO2 increased by 10–20%, predetermining the predominance of mineralization processes. The considered post-fire transformation of the structural and functional parameters of soil microbiocenosis, as well as a 20–40% decrease in the total carbon storage of microbial biomass in the soils of all sites demonstrate a long recovery period of soils after fires in light coniferous and deciduous forests of the central regions of the Zabaikal krai.

Calcium Losses from Reclaimed Sod-Podzolic Light Loamy Soil at Different Levels of Moisture Availability

In a 10-year laboratory experiment on columns, the migration mobility of calcium remaining in dolomite-reclaimed sod-podzolic soil after harvesting crops was studied. A “fund” of calcium compounds capable of migration in years with average long-term, excessive and insufficient levels of moisture has been identified. It was found that an increase in the volume of drained moisture contributed to an increase in unproductive calcium losses. The higher the dose of dolomite and the smaller the particle size, the greater the eluvial calcium loss. It is shown that the bulk of the calcium capable of migration was removed from the soil at the initial stage of washing. During the entire study period, migration calcium losses after pea harvesting exceeded losses after mustard cultivation. Empirical dependences describing the loss of calcium from the soil produced by dolomite in a wide range of doses have been developed. Various variants of the experiment were ranked according to the scale of calcium losses. It is shown that over 10 years of observations, the maximum calcium losses as a result of migration were characteristic of the variant of the experiment produced by dolomite flour calculated from the full dose of hydrolytic acidity. Calcium losses from soil reclaimed by dolomite particles of 5–7 and 7–10 mm in doses equal to 3 and 5 Hc were less.Key words: sod-podzolic light loamy soil, soil moisture availability, chemical reclamation, eluvial calcium losses, empirical models of migration process.

Replenishment of Humus due to Crop-Root Residues in Flax and Crop Rotations

In the Central region of the Non-Chernozem zone of Russia on sod-podzolic light loamy soil in a long stationary experiment in flax crop rotations, the process of replenishing humus due to crop-root residues was studied. Alternation of crops in the crop rotation in 2004–2011: pure steam – winter rye with sowing of perennial grasses (red clover and timofeevka) – perennial grasses of the 1st year of use – perennial grasses of the 2nd year of use – flax – potato – barley – oats. In 2012–2018, potatoes were excluded from the crop rotation. The contribution of cultivated crops to the accumulation of soil organic matter varied. The largest amount of crop-root residues (6.8 t/ha) remained in the soil after harvesting perennial grasses, which provided a positive humus balance of +1.35 t/ha. In the crop rotation with potatoes without the use of fertilizers, the humus deficit was –0.20 t/ha, with the exclusion of potatoes from the crop rotation, the deficit decreased to –0.05 t/ha per year. The use of fertilizers increased the productivity of crop rotations by an average of 75%, the amount of crop-root residues increased by 10.6 t/ha or 58%, which allowed to obtain a positive balance of humus in the soil. The use of fertilizers at a dose of (NPK)200 (manure 5 t/ha + (NPK)135 and manure 5.7 t/ha + (NPK)120) in an 8-pole crop rotation with pure steam and potatoes when saturated by 25% with perennial grasses provided a humus balance of +0.17 t/ha per year, in 7-full crop rotation with pure steam and without potatoes at saturation by 28.5% with perennial grasses – +0.43 t/ha per year.

Influence of Mineral Fertilizers on the Dynamics of Biomass Aaccumulation and Plant Growth of Winter Rye

The dynamics of biomass and height of Secale cereale L. plants was studied in a long-term stationary field experiment on sod-podzolic light loamy soil. Systematic application of mineral fertilizers (option 2 – N65P50K50, option 3 – N100P75K75) had a significant impact on the height and biomass of plants at all tested stages of vegetation (eight time points within 50 days). To describe the dynamics of biomass and height of Secale cereale L. plants, sigmoid (logistic) and linear models are well suited, which made it possible to calculate such parameters as maximum biomass and height (M2, g : H2, cm), maximum speed (Vmax, g ⋅ day–1 (cm ⋅ day–1)) and average speed (b, g ⋅ day–1 (cm ⋅ day–1)). The Vmax values of the growth of raw plant biomass in variants 2 and 3 exceeded this indicator for the control variant by 1.7–2.0 times; Vmax of plant height growth varied within 4.2–4.6 cm ⋅ day–1, did not depend on the application of mineral fertilizers. The application of mineral fertilizers led to an increase in the average growth rate of the biomass of plants Secale cereale L. (b, g ⋅ day–1), in relation to the control, by more than 2 times.

The assessment of blue lupine varieties according to productivity and adaptability in the conditions of Kirov region

The article provides the results of the comparative study of grain productivity of 7 blue lupine (Lupinus angustifolius L.) varieties bred by the All-Russian Scientific Research Institute of Lupine in the conditions of Kirov region on sod-podzolic light loamy soil. It has been established that the yield of the seeds of blue lupine varied 1.5-2 times over the years of cultivation (2000-2022) depending on the weather conditions. Over 3 years on the average the varieties Bryansky kormovoy and Siderat were the most productive, 46-287 and 281 g/m2, respectively. Even in extremely unfavorable for blue lupine 2022 (by environment condition index of 62) these varieties significantly exceeded the control (Vitayz – 135.8 g/m2) in yield, by 72.9 and 61.1 %. The coefficient of adaptability of the varieties Siderat 46, Smena, Uzkolistny 53, Bryansky kormovoy was over 100 %. The productivity structure elements of blue lupine, namely: the number of beans per plant, the number of grains per bean and mass of 1000 seeds depended on hydrothermal conditions of the growing period. Under favorable conditions the number of beans per plant and the size of seeds increased. The number of grains per bean was the most stable indicator. The average duration of the growing period of lupine varieties was 84-91 days. In hot and dry weather of 2022 the ripening began 5-7 days earlier than long-time average annual periods. The varieties with highly developed side branching had a longer growing period – Bryansky kormovoy, Uzkolistny 53 and. Vitayz. During the year favorable by hydrothermal conditions the raw protein content in lupine seeds was 30.8-36.5 %. In unfavorable years it decreased by 20-45 % depending on the variety.

Changes in Agrochemical Properties of Sod-Podzolic Soil and Productivity of Grain-Grass Crop Rotation Depending on Nutrients Balance

In a stationary field experiment on soddy-podzolic light loamy soil, the influence of fertilizer systems (organic, mineral, organo-mineral) and liming on the balance of nutrients, changes in the agrochemical parameters of the soil and the productivity of grain-grass crop rotation was studied. At the end of the 1st rotation of the five-field crop rotation, a medium-strength correlation (0.51) was revealed between the potassium balance and the change in its content in the soil, determined in an extract of 0.2 n. HCl (according to Kirsanov method). It was established that liming at 1.0 Ha of slightly acidic soil increased the productivity of crop rotation by 10%, which in turn led to an increase in the removal of nitrogen, phosphorus and potassium with crop yields by 10-14%. A positive balance of phosphorus was achieved only in the variant with an organo-mineral fertilizer system when applying manure and mineral fertilizers in full dose. It should be emphasized the need to take into account the return of nutrients with straw, in case of plowing in the field. It was revealed that in the organo-mineral fertilizer system, the share of biological nitrogen entering during the plowing of the clover layer is 26-28%, and about 20-23% more N is supplied during the plowing of straw. It was noted that when calculating the nitrogen balance, it is necessary to take into account its supply not only with mineral fertilizers, but also due to biological nitrogen fixation, when incorporating straw, etc. Failure to take into account these sources can lead to serious miscalculations. The organo-mineral system provided the highest productivity of the grain-grass crop rotation - 5.16 t of grain units/ha on an unlimed background and 5.73 t of grain units/ha with liming. On a slightly acidic background, the organic and mineral fertilizer systems ensured an equal crop rotation productivity of 4.28 t of grain units/ha, while liming had a slight advantage for the mineral system.

Chemical Composition of Spring Wheat Plants on Acidic Sod-Podzolic Light Loamy Soil, Calcified by Calcium-Containing Industrial Waste. Empirical Models of Translocation of Macro- and Microelements into Vegetative

In 2 vegetation experiments laid on acidic sod-podzolic light loamy soil, a comparative study of the fertilizing value and reclamation properties of finely ground dolomite flour (DF) particles used for road construction and blast furnace slag (FS) of a metallurgical plant was carried out. It was found that 1 year after liming, DF, introduced in doses equivalent to FS in terms of neutralizing ability, contributed to a greater shift in pHKCl and a greater accumulation of the sum of the exchange bases Ca2+ + Mg2+. In terms of the effect on the productivity of wheat straw, variations with FS, introduced in equal amounts with DF, were not inferior to the latter. The effect of liming DF on wheat grain yield was more significant than with FS. The relationship between the content of mobile Ca2+ + Mg2+ cations in reclaimed soil and the productivity of wheat grain was revealed. Empirical dependences describing the effect of increasing doses of meliorants on the transition of calcium, magnesium, zinc, iron and manganese into straw and grain of plants have been developed. It is concluded that at the first stage of the dissolution of meliorants, their chemical nature was the leading factor in achieving the effect of curing. The degree of grinding of lime materials was of secondary importance.

Efficient control of the productivity of agrophytocenosis of soybean (Glicyne max (L.) Merill)

Around the world, there is a surging demand for soy, the ‘king of beans’. Soy is a globally traded foodstuff produced in both temperate and tropical regions and is a major source of protein and vegetable oils. In the conditions of the Kaliningrad region, the duration of soybean vegetation in soddy-weakly podzolic gleyic light loamy soil, with the medium reaction close to neutral, high and very high content of mobile phosphorus, and exchangeable potassium attains 144 days. The agrophytocenosis productivity is controlled through application of different mineral and bacterial fertilizers. Analysis of variance of the experimental data obtained in the study showed a pronounced relationship of 0.71 for the effect of the fertilizer system on quantitative indicators of the biological yield of soybean seeds. The effectiveness of the microbial-plant system of soybean cultivar Merlin and strains of nodule bacteria Bradyrhizobium japonicum, under optimal conditions, increased the crop yield to 4.43 t/ha, which is 2.11 t/ha higher compared to the control and 1.01 t/ha higher relative to the experimental option with carbamide fertilizer.

The effect of correlation between a spring wheat variety with soil tillage technologies and doses of nitrogen fertilizers on the interannual yield stability

There was studied the possibility of reducing the effect of weather conditions on spring wheat productivity in the Non-Blackearth zone due to improving tillage technologies. There has been established that on soddy-podzolic light loamy soil, on the fields of the Ivanovsky Research Institute of Agriculture in the period 2013–2019, the difference in the number of productive stems per m2 when using plowing or minimal tillage was not significant when the HTC changed from 0.73 to 2.65, except the year of 2017 (HTC = 2.19), when there was increased soil moisture throughout the vegetation period. The advantage of minimal tillage under these conditions was 30 %. According to number of kernels per ear, there was identified a significant advantage (more than 20 % (HTC = 2.65; 0.99)) of plowing over minimum tillage (by 13–14 %) during the years with soil moisture in the wheat booting stage. When applying experimental tillage, there have been formed areas with a variable density in the lower part of the arable layer, each of which is favorable for plant development under a certain soil moisture. The transition to experimental tillage has increased number of productive stems on 1–6 %. Number of kernels per ear when using experimental tillage significantly exceeded this indicator (by 5–18 %) under a minimum tillage in the entire range of moisture. Compared to plowing, the advantage of experimental tillage according to number of kernels per ear was 0–27 %. The effect of weather conditions on a number of productive stems was 74.8 %, and number of kernels per ear was 32.4 %. The effect of mineral fertilizers on these parameters of the yield structure was 1.8 and 26.2 %, respectively.

PROSPECTS OF SOYBEAN GROWING IN THE WESTERN POLISSIA ZONE

Modern climatic changes, namely significant warming in the northern Forest-Steppe and Polissia zones of Ukraine, provide opportunities for growing a number of grain and leguminous crops (maize for grain, soybeans, sunflower, and others), previously unusual for this region. Among the above-mentioned crops, soybean is a crop that can significantly improve the nitrogen balance of the soil without the use of mineral fertilizers; its cultivation to some extent can be an alternative to expensive nitrogen fertilizers because, under the condition of inoculation, soybean can leave up to 80 kg/ha of biological nitrogen, which equivalent to 300 kg of ammonium nitrate, which is enough for forming decent harvest of winter wheat or corn. The analysis of meteorological data shows that when having the current amount of heat supply during the growing season in the Western Polissia zone, it is possible to grow ultra-early and early-ripening soybean varieties with a duration of the growing season of up to 90-100 days and a required number of heat units - up to 2400-2500 CHU. It was established that the main factor limiting the cultivation of soybeans on the peat soils of the Western Polissia zone is a significantly shorter frost-free period (compared to the adjacent sod-podzolic soils on dry land). Therefore, for growing on peat soils, it is necessary to choose ultra-early varieties of soybeans with a growing season of up to 85 days and the required number of heat units - up to 2400-2500 CHU. That will allow obtaining physiologically ripe seeds before the onset of the first autumn frosts, which in some years can already occur in the first decade of September. On peat soils, the yield of the Yunka soybean variety by the variants of the experiment ranged from 15,1-24,8 t/ha, while on the adjacent sod-podzolic light loamy soils it was 30,3-46,8 t/ha. The reason for the significantly lower soybean yield on peat soils is a short frost-free period compared to sod-podzolic soils, which did not allow the studied varieties to fully realize their potential for 2 years in a row. The research has established that on sod-podzolic light loamy soils of the Western Polissia zone, under favorable conditions, the yield of such ultra-early and early-ripening soybean varieties as Yunka and Astor of the Sevita genetics selection (Canada) can be up to 45,0-46,8 t/ha. The use of Rizofix inoculant in a combination with Rice Pi phosphorus-mobilizing product allows increasing the productivity of soybeans to 6,7-7,0 t/ha. Additional profit from their use is about 8-8,3 thousand hryvnias from 1 ha.