Content Of Mobile Phosphorus Research Articles

Differentiated Fertilization in the System of Precision Farming on the Complex of Gray Forest Soils in Vladimir Opolye

The studies were carried out in a long-term stationary field experiment from 1997 to 2008 on gray forest soils of Vladimir Opolye. The soils of Vladimir Opolye are distinguished by a high complexity and heterogeneity of the soil cover. The higher potential fertility is possessed by the soils with the 2nd humus horizon, the lower–by the gray forest non-podzolized soils. This heterogeneity leads to the “variegation” of crop yields. As a result of the experiment, it was established that when applying high doses of mineral fertilizers, the content of mobile phosphorus and exchangeable potassium increases, but the physicochemical and chemical properties of the soil deteriorate. Exchangeable and hydrolytic acidity increases, and the humus content decreases. This leads to a decrease in crop yields. The use of differentiated doses of fertilizers–low on soils with a 2nd humus horizon and high on gray forest and podzolized soils–will make it possible to achieve an even yield of agricultural crops, reduce the unproductive costs of mineral fertilizers and improve the ecological state of agricultural landscapes.

50­річна динаміка вмісту рухомих сполук азоту, фосфору і калію в чорноземі опідзоленому за даними стаціонарного польового досліду

Goal. To establish the regularities of dynamics of changes in the supply of basic nutrients at the systematic use of mineral fertilizers and after the cessation of their application. Methods. Statistical-mathematical analysis of observations on the content of mineral nitrogen, mobile phosphorus, and potassium in degraded chornozem of the stationary field experiment with fertilizers in 1970 -2020 on the territory of SE «SF Hrakivske» of NSC ISSA named after O.N. Sokolovskyi» (Kharkiv district, Kharkiv oblast). Results. Without the use of mineral fertilizers, the content of mineral nitrogen in the arable layer of the soil depends on the number of deposits and mostly corresponds to gradations of very low or low levels, and the content of mobile phosphorus and potassium corresponds to the limits of low and medium supply of these elements. With the systematic application of mineral fertilizers, the content of mobile phosphorus and potassium in the soil increases at the rate of 50 kg of the active substance (a.s.) per 1 ha with an intensity of 2.3 mg/kg per year and 1.2 mg/kg per year, at the rate of 100 kg a.s. per 1 ha — 3.1 mg/kg per year and 2.4 mg/kg per year, respectively. The consumption of phosphorus fertilizers to change the content of mobile P2O5 in the arable soil layer by 1 mg/kg depends on the duration of systematic fertilization and is 13.1-25.9 kg of P2O5 per 1 ha. The cost of potassium fertilizers to change the content of mobile K2O in the arable soil layer by 1 mg/kg is much higher than phosphorus and on average during the experiment was 49.5 kg a.s./ha. After the cessation of fertilizer application, there was a decrease in the content of mobile phosphorus in the soil in the first 10 years by 5.5 mg P2O5/kg per year, 20 years — by 4.8 mg P2O5/kg, for 30 years — by 4.1 mg P2O5/kg. The reduction of mobile potassium content in the soil after the cessation of fertilizer application is almost twice as fast as phosphorus. Conclusions. Using modeling of different levels of mobile phosphorus and potassium, the intensity of changes in the trophic state of the soil with the systematic application of mineral fertilizers under field crop rotation and after the cessation of fertilization. The estimated costs ic calculated of the active substance of phosphorus and potassium fertilizers to increase the content of mobile phosphorus and potassium by 1 mg/kg of soil, as well as the intensity of its reduction with extensive use of chornozem (without mineral fertilizers).

ОЦЕНКА ДИНАМИКИ ОСНОВНЫХ АГРОХИМИЧЕСКИХ ПОКАЗАТЕЛЕЙ КАШТАНОВЫХ ПОЧВ НА ОРОШЕНИИ В УСЛОВИЯХ РИСКОВАННОГО ЗЕМЛЕДЕЛИЯ СТАВРОПОЛЬЯ

Irrigation is an important element of agricultural production in the arid conditions of the Stavropol Territory. The combination of irrigation, chemicalization and complex mechanization provides highly productive use of land that requires specific scientific support. The purpose of the research is to identify differences in the dynamics of the main agrochemical indicators (organic matter, pH, mobile phosphorus, mobile potassium) on irrigated and non-irrigated chestnut soils. The object of research is chestnut soils located in an extremely arid climatic zone of the Stavropol Territory. The data of complex monitoring of soil fertility in the Apanasenkovsky district were used as the source material. The data for the period from 1991 to 2020 were prepared by the staff of the State Center for Agrochemical Service “Stavropolsky”. The content of soil organic matter was determined by the Tyurin method in the modification of CINAO. Mobile compounds of phosphorus and potassium were determined by the Machigin method in the modification of CINAO. The value of the hydrogen pH index of the aqueous suspension was determined by the potentiometric method. The content of organic matter in chestnut soils increased from 1.8 to 2.0–2.1% both on irrigated and non-irrigated lands. A tendency to leaching of irrigated lands by 0.2 units has been revealed; therefore, in this case, it is recommended to use chemical ameliorants. Moreover, on irrigation, an increase in the content of mobile phosphorus (from 0.8 to 4.0 mg/kg) compared to non-irrigated areas was revealed. The reason for this is the increased doses of phosphorus-containing fertilizers applied during irrigation. During the study period, the content of mobile potassium increased from 77 to 93 mg/kg irrigated chestnut soils compared to non-irrigated ones. The negative dynamics in the content of mobile potassium on irrigation was revealed. It amounted to 364 mg/kg (as of 2020), which is lower than the data of the previous survey period by 81 mk/kg. Particular attention should be paid to the use of potash fertilizers since there is increased removal of this element, despite the high potash potential of chestnut soils in the arid zone of the Stavropol Territory.

Influence of conditions of mineral nutrition, clean and occupied fallows on the fertility of the chestnut soil of the Eastern Ciscaucasia

In conditions of a shortage of manure and high prices for mineral fertilizers, the preservation and improvement of soil fertility is an urgent problem of agriculture. The studies were carried out at the Prikumsk experimental selection station in two 6-field crop rotations from 1969 to 2019 The purpose of the research is to study, in a long­ term stationary experiment on various nutritional backgrounds, the effect of grain crop rotations with clean and busy fallow on the fertility of the chestnut soil in the arid zone of the Stavropol Territory. In the grain-and-row crop rotation with 16.6% of pure fallow, the decrease in the humus content in the control was 0.10%, the humus reserves were 2.6 t/ha, against the fertilized background — 0.09%, 2.3 t/ha, and with the occupied fallow on the contrary, it increased by 0.10%, 2.6 t/ha and 0.11%, 2.8 t/ha. The content of mobile phosphorus in the topsoil in the control with clean fallow increased by 1.7 mg/kg, stocks — by 4.3 kg/ha, with occupied fallow — 3.4 mg/kg and 8.7 kg/ha, and on the fertilized variant — 7.5 mg/kg, 19.1 kg/ha and 7.4 mg/kg and 18.9 kg/ha. The content and reserves of exchangeable potassium increased by 3 — 46 mg/kg and 8 — 115 kg/ha. In the crop rotation with clean fallow, they were 4.2-4.1 times lower on the control, and 13.7-13.0 times lower on the fertilized background, compared with the occupied fallow. The application of fertilizers contributed to a decrease in the potassium content in the crop rotation with clean fallow by 3.7 times, reserves by 3.5 times, and with busy fallow by only 12.2 and 10.6%. Sainfoin fallow significantly increased the content and reserves of potassium in the soil in the control and significantly reduced its consumption in the fertilized variant.

The Dynamics of the Reduction of Arable Land Areas According to their Long-term Monitoring in the Tomsk Region

The results of agroecological monitoring of arable and fallow lands are considered. It has been established that the content of humus and mobile phosphorus in the soils of the fallow, as well as the value of the salt pH, is lower than on arable land; mobile potassium is higher. This may be due to the migration of deposited potassium from the lower soil horizons into the humus horizon and its release from the absorbed state during the decomposition of organic matter. It was revealed that in fallow soils, the content of mobile phosphorus in the range of 150–600 mg/kg directly correlates with the value of salt pH (4–6 pH units), while this dependence is not observed on arable land.

Nutrient regime of irrigated meadow-chernozem soils under long-term intensive use

The patterns of phosphorus and potassium status of soils were studied given the improvement of agricultural technologies of irrigated agriculture. Long-term studies were carried out in an experimental grain-grass crop rotation on irrigated meadow-chernozem soil. The experimental plot is located in the southern forest-steppe of Omsk region. Intensive use of irrigated arable land with a rational combination of moisture and mineral nutrition regimes contributes to obtaining maximum yields of forage and grain crops. The creation of various conditions for mineral nutrition due to an increased and high supply of mobile phosphorus and with the application of different options of agricultural technologies made it possible to simulate possible agro-ecological conditions that form contrasting indices of crop productivity. A comparative assessment of the effectiveness of various agricultural approaches to growing crops under irrigation conditions indicates that soil cultivation techniques and forecrops did not significantly affect the content of available phosphorus in the soil. The equilibrium content of mobile phosphorus given a long-term negative balance changed insignificantly. The systematic application of phosphorus-containing fertilizers significantly increased the phosphate status of the soil. However, an adequate assessment of the phosphate status of arable soils is possible using several diagnostic indices (methods). Long-term intensive use of irrigated arable land has reduced the reserves of easily exchangeable potassium from 4 to 1–2 mg/100 g of soil in the arable layer. The content of exchangeable potassium has also decreased by almost 2 times, but the soil remains in a high and very high class of its availability. However, a number of indicators show its increasing depletion in the most mobile fractions of soil potassium. The reserves of non-exchangeable potassium are more stable, which have decreased by about 19% over 40 years, and the soil has passed into the category with an unstable supply.

Fertilization Systems and Effects of Their Long-Term Application on the Fractional Composition of Mineral Phosphates and Mobile Phosphorus Content in the Profile of Sod–Podzolic Soils

Fertilization Systems and Effects of Their Long-Term Application on the Fractional Composition of Mineral Phosphates and Mobile Phosphorus Content in the Profile of Sod–Podzolic Soils

Влияние гуминового препарата «BIO-Дон» на содержание элементов питания в почве и качество черешни

The work deals with the study of the influence of humic preparation ‟BIO-Don” on indicators of soil fertility, the enzymatic activity of Сalcic Chernozem (Pachic) at the experimental site, as well as on the productivity and quality of fruit crops, for example, cherries varieties Talisman and Vasilisa in terms of work experience in the open ground in the territory of «Agrofirm “the Red garden”». Treatment of fruit trees was carried out once by drip irrigation in a dosage of 300 l/ha of working solution with a concentration of gp 0.008 g/l for carbon, soil samples were taken before treatment, two weeks and a month after the application of the humic preparation, a site without the use of “BIO-Don” was used as a control option. The treatment of plants with a humic preparation increases the activity of the enzymes catalase, invertase and phosphatase, especially during the period of mass ripening of fruits. Accordingly, at the same time, the content of mobile phosphorus and exchangeable potassium decreases, which is due to the increased removal of these elements by plants. Chemical analysis of fruit products for the content of soluble solids and titrated acidity revealed a statistically significant increase in these indicators in fruits from areas treated with humic preparation, which is manifested by their greater taste saturation.

РОСТ И БИОЛОГИЧЕСКАЯ ПРДУКТИВНОСТЬ РАСТЕНИЙ ПОСЛЕ ОБРАБОТКИ МИКРОЭЛЕМЕНТНЫМ СОСТАВОМ

In laboratory conditions, the effect of sodium selenite and a mixture of sodium selenite and zeolite on the growth and biological productivity of peas was investigated. The soil was examined after harvesting. It was shown that the addition of both sodium selenite and the mixture of sodium selenite with zeolite to the soil with irrigation affects the development of the root system - the length of the main root in the first case increased by 16.5%, the height of the stems 30 days after planting was 29% more in comparison with the control variant, and in the second case, the length of the main root increased by 18.5%, the height of the length of the stems increased by 24% than that of the control. Processing of peas with microelements also caused a stimulation of the reproduction system: an increase in the number of inflorescences by 3 times and the number of beans in 3.4 times compared with the control. A 160-fold decrease in the selenium content and the introduction of zeolite did not cause a large difference in the obtained results (except for the number of beans - with the addition of zeolite, the number of beans increased by 8%). Biochemical indicators of pea biomass showed an increase in dry matter, in sugar content by 28.8%, but a decrease in crude protein by 17.7%, a decrease in carotene by 17.5%, nitrogen by 18% (when irrigated with sodium selenite). When treated pea with sodium selenite and zeolite, the sugar content increased by 85.5%, but it was observed a decrease in crude protein by 9.5%, in crude fat - by 16.5%, a decrease in carotene by 31.2%, a decrease in nitrogen by 9.4%. Analysis of the soil after harvesting showed in the option with the addition of sodium selenite a decrease in the amount of humus by 6.5%, mobile potassium by 18.5%, but an increase in mobile phosphorus by 6.6%, mobile calcium by 2.7%. In the option with the introduction of the mixture of sodium selenite and zeolite, no decrease in humus was observed, the content of mobile potassium decreased by 10.8%, the content of mobile phosphorus increased by 9.8%, mobile calcium by 3.5%. The acidity of the soil has not changed.

Влияние высоких доз суперфосфата на групповой и фракционный состав фосфатов темно-серой лесной почвы

Abstract. The purpose of the work was to study the effect of high doses of superphosphate on the yield of forage beans and the composition of phosphates in dark gray forest soil. Research methods. The studies were carried out in a microfield experiment. Doses of superphosphate are calculated taking into account the increase in the phosphorus content from medium to very high. The total phosphorus content was determined after calcining the soil, and the mineral group was determined in the natural state of the soil in an extract of 0.2n sulfuric acid, the fractional composition was determined by the method of S. Chang and M. Jackson. Results. High doses of superphosphate (the degree of phosphorus supply is high and very high) without the introduction of nitrogen and potassium fertilizers significantly reduce the productivity of beans. The optimal content of mobile phosphorus is an increased degree of supply (101–150 mg/kg according to Kirsanov). High doses of superphosphate double the total phosphate content in relation to the original soil, mineral phosphates make up 77 %, organophosphates – 22.8–23.3 %. Analysis of the fractional composition of mineral phosphates showed that the use of water-soluble phosphorus fertilizers increases the amount of phosphates of all fractions. The fraction of loosely bound phosphates increases from 5 mg/kg of soil (medium supply) to 14 mg/kg at a very high level. From the total amount of mineral phosphates, calcium phosphates occupy 20–23 %, aluminum phosphates – 12.5–14.9 %. The share of ferrophosphates practically does not change with the dose of superphosphate and is 25.3–25.7 %. The fraction of poorly soluble phosphates is the most significant: with an increased degree of supply, the content of phosphates is equal to 438 mg / kg and increases with a very high degree of supply up to 529 mg/kg of soil, this is 37.1–38.8 % of the total amount of the mineral group of phosphates. The scientific novelty lies in the calculation of the dose of phosphorus fertilizer, taking into account the stepwise transition from one degree of provision to another, from medium to high, high and very high. This approach to calculating the doses of fertilizers makes it possible to differentiate the doses of nitrogen-potassium fertilizers.

Phosphorus fertilizer payment taking into account its long-term after-effect

When phosphorus and nitrogen fertilizers are used together, their interaction is positive. This relationship is expressed differently in different weather conditions. Its manifestation also depends on elements of culture cultivation technology. In order to optimize phosphorus nutrition, pre-determined doses of phosphorus are offered, sometimes highly overestimated, which should have a long-term follow-up. To control the content of mobile phosphorus, doses of phosphorus have been developed, which can increase the index of plant availability with this element by 10 mg/kg. In a stationary experiment at the Central Experimental Field of the Kurgan NIISH, the effect of three doses of phosphorus-free nitrogen and combined with phosphorus fertilizer for 25 years and the further follow-up of phosphorus was evaluated. Phosphorus fertiliser was added for 25 years on the background of nitrogen in a dose of P40. Once the phosphorus fertilizer is discontinued, the duration of its follow-up is now 24 years.

Хімічна меліорація кислих ґрунтів з відтворенням і регулюванням їх родючості за біологізації систем удобрення в умовах Лісостепу України

Goal. To study the influence of advanced technologies of defecation on the dynamics of fertility, physicochemical and agrochemical properties of gray forest slightly acidic soil and slightly acidic leached chernozem, the productivity of sugar beets at biologization of fertilizer systems in the Right Bank and Central Forest-Steppe of Ukraine. Methods. Physicochemical and agrochemical analyzes of soil, phenological observations of plant growth and development were carried out. Results. 1.5 dose of CaCO3 calculated according to Ng (9.0 and 7.5 t/ha in physical weight) was determined to be the most effective for the soil-harvesting complex of gray forest weakly acidic soil and typical leached weakly acidic chernozem. The maximum neutralization of soil acidity was achieved: the pH of the soil solution increased to 7.2 and 6.9, the hydrolytic acidity of soils decreased to 0.42 and 1.0 cmole/kg of soil with an increase in the number of absorbed bases to 25.7 and 28, 5 cmole/kg of soil and the degree of saturation of the bases up to 95.3 and 97.0%. The most effective rate of defecation in terms of the impact on the content of basic nutrients in the gray forest slightly acidic soil and slightly acidic leached chernozem was 1.5 dose of CaCO3 calculated according to Ng (9.0 and 7.5 t/ha in physical weight). In such conditions, the maximum alkaline hydrolyzed nitrogen content was reached — 207.3 and 140.5, as well as the content of mobile phosphorus — 357.7 and 172.4, potassium exchange — 198.4 and 106.4 mg/kg of soil, respectively. The productivity of sugar beets increased to 52.7 and 67.7 t/ha with sugar harvest — 10.3 and 12.0 t/ha, respectively. Conclusions. The application of defecates on weakly acidic gray forest soil and weakly acidic leached chernozem with improved methods and technologies of application of sugar beet fertilization systems for biologization contributed to the improvement of physicochemical and agrochemical properties of soils while maintaining their fertility and productivity.

Продуктивність міскантусу гігантського та стан родючості ґрунту за внесення добрив

Miscanthus giant is a tall perennial herbaceous plant with a well-developed root system, which is used for biofuel production. The aim of the study was to establish the effect of gi-ant miscanthus in the first year of growing season on the state of soil organic matter, removal and balance of nutrients and biological productivity of crops for fertilization. A four-year survey of the condition of miscanthus plantations was conducted at ‘Veselo Podilska’ research and breeding station during 2016‒2019 in the forest-steppe zone of Ukraine. Indicators of biomass productivity of giant miscanthus and the state of fertility of the grant for fertilizer application in the area of the left-bank of the Forest-Steppe of Ukraine for the production of solid biofuels are characterized. In the first year of the growing season, giant miscanthus produces more organic matter in the root system than in its terrestrial biomass ‒ 2.5 and 1.6 tons of dry matter/ha, respectively. It was found that foliar fertilization with microfertilizers significantly increased the yield of terrestrial biomass of giant miscanthus in the background of mineral fertilizers. The highest biological yield of ground mass of giant miscanthus was achieved with the introduction of N60P60K60 and two foliar fertilization with microfertilizer Vympel-K, 0.5 l/ha: yield of terrestrial biomass ‒ 3.1 tons of dry matter/ha with the advantage of control without fertilizers ‒ 1.5 tons/ha. In the first year of cultivation miscanthus giant uses a small amount of nutrients from the soil: nitrogen ‒ 20.4‒33.8 kg/ha, phosphorus ‒ 3‒5.3 kg/ha, potassium ‒ 6.1‒12.4 kg/ha . The application of N30P30K30 ferti-lizers was sufficient to form a balanced and expanded balance of nutrients in the soil. The appli-cation of mineral fertilizers did not affect the dynamics of organic matter in typical chernozem. Growing giant miscanthus in the first year of the growing season ensured the stability of the or-ganic matter content in the soil at the level of 4.04‒4.11%. At the same time, the content of mobile phosphorus at the end of the growing season decreased by 17‒18 mg/kg, potassium ‒ by 13‒43 mg/kg of soil. Reducing the content of mobile forms of phosphorus and potassium in the soil at the end of the growing season leads to efficient use of plant nutrients, chemical transformation of phosphorus into insoluble compounds and non-exchange adsorption of potassium ions by the soil complex in the biocenosis of miscanthus.

Nutritional Regime of the Soil and Growth Activity of the Apple Tree Root System in Orchards with Legume-Cereal Grass Intercropping

This work aims to study the influence of legume-cereal grasses in the inter-row spacings of the garden on the content of nutrients in the soil and the growth of apple tree roots. The amount of nitrate nitrogen was in direct proportion to the ratio of the legume component in the phytocenosis. The nitrogen content in the control option was the smallest: 19.7 mg/kg in the soil layer of 0-30 cm and 13.4 mg/kg in the layer of 30-60 cm. In the case of natural grassing-down between rows, cereal forbs prevailed. The largest amount of nitrate nitrogen was achieved when sowing the red clover and timothy grass in a ratio of 7:3. The accumulation of nitrate nitrogen is due to the activity of nodule bacteria on the roots of red clover. The accumulation of mobile phosphorus and exchangeable potassium depends on the amount of mowed mass in the inter-row spacings of the garden. The lowest content of mobile phosphorus was detected for natural grassing. In the control option, its amount was 118 mg/kg. In the 0-30 cm soil layer, the content of mobile phosphorus was 127.4-142.6 mg/kg depending on the ratio of legume-cereal grasses, and it amounted to 95.1-103.2 mg/kg in the 30-60 cm layer. For the ratio of red clover and timothy grass 3:7, the highest phosphorus content was detected. The intercropping of the garden with a legume-cereal herbal mixture also contributed to a greater accumulation of exchangeable potassium in the soil relative to natural grassing-down - 122.3-134.9 mg/kg. The optimal ratio of legume-cereal component was 3:7. A higher growth activity of the roots of the apple tree was noted in the option with sodding with a mixture of red clover and timothy grass in a ratio of 7:3.

Accumulation of pigments in wheat leaves under influence of macronutrients

On natural acidic soil, statistically significant relationships between wheat yield and pigment content in leaves were established (for Chl a r = 0.910…0,949; Chl b = 0.925…0,967; for carotenoids in 2017 = 0.887;). Nitrogen fertilizer promoted an increase in pigment content in leaves (Chl a and Chl b - by 38…43%, carotenoids - by 16…22%). At phosphorus application, the content of chlorophylls increased by 44…83%, carotenoids - by 20…37%. The content of mobile phosphorus in the arable layer of natural acidic soil is statistically significantly associated with the content of Chl b (r = 0.738 and 0.793 for 2017 and 2020, respectively) and the part of pigments included in light-harvesting complexes (r = 0.799 and 0.829, respectively). In 2020, statistically significant associations of mobile phosphorus content in soil and weight ratios of Chl a / Chl b (r = -0.815) and (Chl a + Chl b) / carotenoids (r = 0.840) were noted. Soil liming reduced the influence of phosphorus on the pigment complex of leaves: against a natural background, the increase in Chl content was 27…40%, against a limed background – 27…29%; for Chl b - on the contrary, liming increased its content by 93…108%, while on a natural background - only by 63…84%. On both soil backgrounds, the addition of phosphorus reduced the carotenoid content in wheat leaves (on a natural background - by 7…9%, on limed - by 17…23%).

Influence of primary tillage on agrochemical indicators of soil fertility

The influence of primary tillage practices (plowing, subsurface tillage, surface tillage, direct sowing (No-till)) on the indicators of soil fertility of typical chernozem in Kursk Region on peas was studied. It was found that with the minimization of tillage humus content in the soil increased, especially in the upper 0-10 cm layer. Acidification of arable soil layer was noted when plowing was used. The content of mobile phosphorus, as well as the degree of its mobility, significantly increased with boardless tillage methods in comparison with moldboard plowing. The maximum amount of exchangeable potassium and the degree of its mobility were in case of direct sowing. The highest level of mineral nitrogen in the layer of 0-20 cm was formed in case of plowing, and its minimum level was formed in case of direct sowing. When tillage was minimized, the topsoil was differentiated by the content of mobile forms of copper, zinc and manganese. In a layer of 0-10 cm, combined tillage, surface tillage and direct sowing increased the content of mobile trace elements compared to a layer of 10-20 cm. When plowing was used as a primary tillage method, the content of mobile copper, zinc and manganese was higher in the layer of 10-20 cm.

Changes in Agrochemical Parameters of Typical Chernozem Soils Caused by Various Cultivation Techniques, Chemization, and Biologization

This paper examines effects caused by basic soil cultivation techniques combined with the integrated application of mineral fertilizers and biopreparations amid the manure and green manure aftereffects on the agrochemical parameters in the arable (0–25 cm) and subsurface (25–50 cm) layers of typical chernozem soils. It is established that disk plowing significantly (by 2–4 times) improves all agrochemical parameters in both layers in comparison with the control soil. The aftereffect of manure increases the efficiency of disk plowing. The highest humus content (5.4% in the arable layer and 5.1% in the subsurface layer) was registered at the end of the growing season of 2020 after the application of biopreparation V417. At the beginning of the growing season of 2019, the integrated application of mineral fertilizers and the biopreparation ensured the highest content of mobile phosphorus and potassium in both layers: 36 and 290 mg/kg in the arable layer and 32 and 220 mg/kg in the subsoil layer, respectively. The highest nitrate nitrogen content was reached at the end of the growing season of 2020 as a result of the biopreparation application amid the aftereffect of spring rape green manure: 28 mg/kg in the arable layer and 21 mg/kg in the subsoil layer. In the course of the experiment, the content of humus and mobile potassium increased from the low to the medium level, while the content of nitrate nitrogen and mobile phosphorus increased to the elevated level. By its aftereffect, spring rape is a more efficient green manure culture in comparison with the mix of spring oats and forage sorghum. In 2020, the efficiency of the spring rape aftereffect was only 10% lower in comparison with manure; therefore, taking the low availability of manure, green manure can be considered a worthy alternative to it. Combined with the application of mineral fertilizers and biopreparation V417, disk plowing performed amid the green manure (spring rape) aftereffect makes it possible to preserve and restore the fertility of chernozem soils in the Chechen Republic and reduces mechanical impacts on them. Surface tillage with disk harrows combined with the use of green manure is a preferable cultivation method for arid regions featuring dry growing seasons.

Засоренность и продуктивность посевов горчицы белой (Sinapis alba L.) в зависимости от нормы высева и дозы азота

Currently, one of the most urgent tasks facing humanity is the preservation of the environment. Development of agricultural practices aimed at reducing chemical load when growing white mustard helps to reduce the negative impact of human agricultural activities on the environment. The aim of the research was to determine seeding rates andN fertilizer dosesat which white mustard plants will actively suppress weeds without overall yield decrease. The studies were carried out in 2017–2019. Soil – chernozem southern low-humus (humus content – 2.08–2.31 %). The content of mobile phosphorus and potassium (according to Machigin method) is 62–90 and 389–586 mg/kg soil, respectively. The experimental design included: Factor A – five options of N fertilizer application: N0 (control variant), N20, N40, N60 and N80; Factor B – six options of seeding rate: 0.5, 1.0, 1.5, 2.0, 2.5 and 3.0 million per hectare. Crop under study – white mustard variety ‘Raduga’. In the course of the research, we have found that the competitive ability of mustard plants against weeds increased with an increase in seeding rate, regardless of the weather conditions of the year. Significant weeds growth and development suppression was noted at a seeding rate of 2 million per ha, the dry weight of one weed in this case was 1.3 g, which was three times less than at a seeding rate of 0.5 million/ha (4.1 g). Seeding rate increase to 2.5 and 3.0 million per ha did not provide reliable suppression of weeds; dry weight of one weed was 1.2 g. The highest seed yield of white mustard (0.6 t/ha) was obtained at a seeding rate of 2 million/ha. This option exceeded others by 0.02–0.14 t/ha. Optimal N fertilizer dose (pre-sowing application) was N60; seed yield of white mustard, in this case, was 0.63 t/ha. Despite the fact that N60 had a positive effect on the growth and development of weeds, it also provided a significant yield increase compared to control – 0.21 t/ha (50 %).

The balance of organic matter and soil nutrients, depending on fertilization level of soybean varieties

The purpose of the research is to study the effect and interaction of straw-litter compost (20 t/ha), ammonium nitrate (30 kg/ha N) and microfertilizer Azosol 36 Extra (2 times 2 l/ha) on the fertility indicators of typical chernozem for soybean cultivation in the southern forest-steppe of the Central Chernozem region. It was found that the increase in fertilization level based on the use of compost contributed to the positive dynamics of organic matter and macronutrients, the formation of higher yields, protein content and collection. The largest increase in organic matter in the soil was in the variants of joint use of compost and ammonium nitrate – 0.52-0.68%. The combination of compost and ammonium nitrate, as well as the complex application of mineral fertilizers, maintained a positive balance of easily hydrolyzed nitrogen in the soil from 3.3 to 8.2 mg/kg. Perhaps, the early-ripening soybean variety Lantsetnaya mainly used nitrogen of mineral fertilizers for crop formation, while the mid-ripening variety Belgorodskaya 48 is more responsive to the use of compost. The introduction of compost also caused an increase in mobile phosphorus content in the soil by 36-47 mg/kg and the exchangeable potassium by 5.4-43 mg/kg. This contributed to the transfer by grouping to a higher gradation - to a high class of supply in terms of the content of both mobile phosphorus (163-196 mg/kg) and exchangeable potassium (125-168 mg/kg).

ОЦЕНКА АДАПТИВНОГО ПОТЕНЦИАЛА ОБРАЗЦОВ PISUM ARVENSE L. ПО МАССЕ 1000 СЕМЯН

The research was conducted in 2018-2020 in the forest-steppe zone of the Krasnoyarsk Territory. The soil of the site is ordinary heavy loamy chernozem, with a low content of nitrate nitrogen (4 ... 6 mg/kg of soil), an average content of mobile phosphorus (19.7 mg/100 g) and a high content of exchangeable potassium (12.6 mg/100 g). Weather conditions during the study period were different in terms of heat and moisture availability of the growing season: 2018-medium arid (SCC 0.60), 2019-insufficiently humidified (SCC 0.89), 2020-sufficiently humidified (SCC 1.32). The object of the study was 9 samples of field peas, the standard is a zoned variety of seed peas, grain-bearing direction, Radomir. The aim of the research was a comparative assessment of the adaptability of the mass of 1000 seeds of collection samples of field peas. The tasks were set to determine the indicators of adaptability of samples by the weight of 1000 seeds: ecological plasticity (bi), homeostaticity( Nom), coefficient of adaptivity (KA), coefficient of multicativity (KM), stability indicator (PUSS); by ranking the obtained indicators, to determine the most adaptive samples of field peas by the mass of 1000 seeds in the conditions of the East Siberian forest-steppe; to determine the variability of the studied indicator by years and to identify correlations of the mass of 1000 seeds with the indicators of adaptability. As a result of the study, it was revealed that in most cases, the adaptive abilities of field peas were higher than those of the standard-field peas, which allows us to recommend Pisum arvense L. to attract Pisum sativum L. to hybridization during breeding. in order to increase the adaptability of the indicator, the weight of 1000 seeds. It was found that Tabyz, Pleiofilia tupe and K-9031 were the most adaptive in terms of the mass of 1000 seeds in the conditions of Eastern Siberia from the studied samples of seed peas. The variability of the trait over the years was insignificant – less than 10%, and only in two variants – Tabyz and K-4375 average-from 10% to 20%. A strong dependence of the mass of 1000 seeds with the following indicators was revealed: Hom homeostaticity (r=0.88±0.17), KA adaptivity coefficient (r = 1.00 ± 0.00) and the PUSS stability level indicator (r = 0.88 ± 0.17); the average with a regression coefficient bi (r = 0.31 ± 0.34) and a weak negative with a multicativity coefficient KM (r = -0.11 ± 0.35)..