FERTILIZER AND HARVEST

Sheudzhen A.Kh., Podkolzin O.A., Marchenko D.K. (agrohemistry@kubsau.ru, dmitri.marchenko@uniferx.com)

Models of productivity of corn plants depending on foliar complex fertilizers when grown in the central zone of the Krasnodar region

DOI 10.24412/1029-2551-2025-3-001

The results of corn plant productivity models aimed at optimizing the fertilizer system of domestic corn hybrids in the Krasnodar Territory are presented. It was found that grain yield was closely related to the area of the assimilation surface and had a significant increase in the fertilized variants. Under dry weather conditions (2021), a nonlinear increase in yield was observed when the leaf area reached 23-28 thousand m2/ha and subsequently decreased sharply. The effectiveness of complex fertilizers with a shortage of precipitation decreased by 3.4-5.3%. A similar pattern has been recorded in the correlation and regression relationship between yield and weight of 1000 grains. With an average and high relationship (R2 = 0.5815-0.8244) between these indicators, the role of complex fertilizers in top dressing increased, and in the control, the coefficient of determination decreased to 0.2821. The positive effect of top dressing was enhanced with increased precipitation and a decrease in temperature conditions.

Keywords: leached chernozem, corn, hybrid, fertilizers, yield, climate change.

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Treshkin I.A., Rabinovich G.Yu. (2016vniimz-noo@list.ru)

Potassium balance in soddy-podzolic soil and crop rotation link productivity under the influence of new organomicroelement complexes

DOI 10.24412/1029-2551-2025-3-002

The article presents the results of three-year tests on the effect of multipurpose compost (КMN) and its modified versions – organo-microelement complexes (OMEC 1: КMN + [Zn + Mo] and OMEC 2: КMN + [Zn + Cu]) on the productivity of the crop rotation link (spring wheat – oats – spring ryegrass), content and the potassium balance in the soil. The ability to prolong the action of the studied fertilizers made it possible to maintain the content of mobile potassium at the level of 91.3-140.4 mg/kg of soil. A statistically significant increase in the content of mobile potassium in soddy-podzolic light loamy soil relative to the variant without fertilizers in the amount of 2.8-7.8% was obtained. The influence of the OMEC 1 on the formation of maximum productivity of the crop rotation link (5.87 t/ha grain units) and an increased level of its growth (36.8%) has been proven. OMEC, due to their constituent trace elements (Zn, Cu, Mo), stimulated increased (1.1-1.4 times) absorption of potassium by plants and its localization in the regenerative organs of spring wheat in the amount of 0.48-0.60%. Potassium removal with the harvest during three years of the experiment increased to 113 and 136 kg/ha when using OMEC and КMN, respectively, and the potassium supply to the soil when plowing in the straw of cultivated crops amounted to 78.3-94.2 kg/ha. The positive average annual potassium balance was 37.9-40.1 kg/ha due to the application of biofertilizers. The coefficient of potassium utilization from fertilizers was calculated in the variant with KMN – 63% and OMEC – 37%.

Keywords: potassium balance, potassium utilization factor, soddy-podzolic light loamy soil, multipurpose compost, organo-microelement complex, microelements, productivity of crop rotation.

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Vasiliev O.A., Korshunov A.P., Kontsevich E.V., Lisitsyn S.V. (vasiloleg@mail.ru, agrohim_21@mail.ru )

Influence of mineral and organic fertilizers on agrochemical properties of soil, yield and quality of hop cones

DOI 10.24412/1029-2551-2025-3-003

When using only mineral fertilizers in the hop field of the Student Scientific and Production Center of the Chuvash State Agrarian University, negative dynamics of the agrochemical properties of the soils was revealed. The organic matter content decreased from 3.59% in 2018 to 2.51% in 2023 (by 30.1% in five years), and by another 12.2% over two growing seasons (2023 and 2024). The exchangeable acidity decreased from 6.00 in 2019 to 4.30 in 2024. The content of mobile phosphorus in the hop garden soil over the same period decreased from 400 to 74 mg/kg, and exchangeable potassium from 325 to 165 mg/kg. The application of organic fertilizers (meat and bone meal, lowland peat, rotted poultry manure) in the spring of 2024 in the experimental variants at doses of 1, 3, and 5 t/ha against the background of the application of mineral fertilizers increased the content of organic matter in the arable layer from 2.07% in the control variant to 2.31-3.20% (in the 5 t/ha variants). The content of mobile phosphorus in the control soil is low (74 mg/kg), the use of organic fertilizers increased it to a maximum of 91 mg/kg in the variant with 5 t/ha of meat and bone meal, to 111 mg/kg in the variant with 5 t/ha of rotted chicken manure and to 133 mg/kg in the variant with 5 t/ha of lowland peat. The mass fraction of exchangeable potassium in the soil in the experimental variants with the application of 5 t/ha increased from 164 mg/kg in the control variant to 218 (meat and bone meal), to 216 mg/kg (rotted poultry manure) and to 207 mg/kg (lowland peat). The yield of hop cones increased in all variants, but a significant increase in yield was only in the variants with the application of 3 and 5 t/ha of organic fertilizers. In all variants, the content of alpha acids in hop cones increased with an increase in the dose of organic fertilizers.

Keywords: alpha acids, yield, hop cones, extended reproduction of soil fertility, typical gray forest soil, hop garden.

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Okorkov V.V., Shchukin I.M. (Okorkovvv@yandex.ru)

Fertilizers, nitrate nitrogen and oat harvest on gray forest soil of the Vladimir Opolye

DOI 10.24412/1029-2551-2025-3-004

On the gray forest soil of the Vladimir Opolye over many years, the effect of fertilizers on the yield of oat grain following spring wheat in the crop rotation was studied: occupied steam (annual grasses) – spring wheat – oats with grass sowing (clover + timothy grass), the dynamics of nitrate nitrogen reserves, the size of their formation by growth and development phases, and the growing season. Over 7 years, the following increases in oat grain were obtained: from the application of doses of complete mineral fertilizer and their combination with cattle manure 11.7-13.9 c/ha, from the aftereffect of doses of manure 3.5-6.0, the action of R40K40 1.9 c/ha. The payback by adding grain to 1 kg of a.s. P₄₀K₄₀ was 3.1 kg, N40P40K40 – 11.6 kg, N₈₀P₈₀K₈₀ – 6.9 kg. First of all, the height of the oat yield was influenced by N-NO₃ reserves formed in the soil layer 0-40 cm before the germination phase and strongly dependent on the air temperature of the 3rd decade of April. The use of nitrogen mineral fertilizers, compared with organic fertilizers alone, accelerated the transformation of soil nitrogen and manure into nitrates before oat seedlings by 1.6-2.0 times, which explained their different effects on crop yields The coefficients of utilization of N-NO₃ reserves formed during the growing season for nitrogen removal by elements of the oat harvest have been determined. They were highest and economically justified when using a single dose of NPK in combination with manure. The annual size of the formation of N-NO₃ reserves during the growing season (mobile nitrogen pool) is proposed to be estimated by the nitrogen mobilization pool, which represents the sum of the use of nitrogen fertilizers and nitrogen reserves in manure with the equivalent of manure fertilizers for nitrogen of 12.3%.

Keywords: gray forest soil, mineral fertilizers, cattle manure, nitrate nitrogen, oat yields, mobile nitrogen fund, nitrogen mobilization pool.

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Grebennikova T.V., Vizirskaya M.M., Onishenko L.M. (tatyana.grebennikova@eurochem.ru, mvizir@gmail.com, d22003803@kubsau.ru)

Evaluation of the efficiency of sulfur-containing fertilizers with different sulfur forms in combination with uan-32 on winter wheat in the Krasnodar region

DOI 10.24412/1029-2551-2025-3-005

The article presents the results of a study evaluating the efficiency of sulfur-containing fertilizers in combination with UAN-32 on the yield and grain quality of winter wheat in the Krasnodar region. Two forms of sulfur were studied: sulfate (AS) and elemental (micronized, MS) at doses of 9 and 15 kg a.i/ha. It was found that the application of sulfur-containing fertilizers increased yield by 19.7-31.5% under favorable conditions (2022) and up to 21.9% in a drought-affected season (2023), with the highest efficiency observed in treatments with micronized sulfur. Sulfur application also contributed to an increase in protein content (up to 1.85%) and sulfur in grain, particularly at a dose of 15 kg a.i/ha. The study revealed that elemental sulfur (MS) is more resistant to leaching under heavy rainfall compared to the sulfate form (AS), making it preferable for regions with unstable moisture conditions. The results confirm the feasibility of incorporating sulfur-containing fertilizers, especially in the MS form, into the fertilization system of winter wheat to enhance productivity and grain quality on leached chernozems.

Keywords: chernozem, fertilizers, nitrogen, sulfur, sulfur forms, wheat, yield, grain, quality.

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Polikarpov A.S., Gasparyan I.N. (antonpolikarpov@list.ru, irina150170@yandex.ru)

Efficiency of molybdenum and boron in increasing of spring rape seeds yield in conditions of the Kaluga region

DOI 10.24412/1029-2551-2025-3-006

The study examines the importance of molybdenum and boron as essential micronutrients for the cultivation of spring rapeseed under the soil and climatic conditions of the Kaluga region. The data obtained provide an understanding of the level of plant demand for these micronutrients, the deficiency of which in soils can lead to decreased productivity, ultimately resulting in lower seed yields. In 2020, field trials showed that the application of boron at a rate of 1.0 kg/ha before and 1.0 kg/ha after flowering increased yield to 12.1 c/ha, which is 28.7% higher compared to the control treatment. The optimal dosage of molybdenum at 0.3 kg/ha applied after flowering increased the yield to 11.3 c/ha – 20.2% higher than the control. According to the 2021 results, the optimal combination was established: boron (1.0 kg/ha) and molybdenum (0.3 kg/ha) applied at different growth stages. Treatment with boron before flowering and with boron + molybdenum after flowering resulted in a yield increase to 13.1 c/ha – 47.2% higher than the control. Proper and targeted use of these micronutrients not only improves yield but also enhances the plant’s resistance to abiotic stresses. The data obtained allow us to assess the synergistic effect of boron- and molybdenum-based micronutrient fertilizers and the strategic importance of their application for optimizing plant nutrition and improving stress tolerance.

Keywords: spring rapeseed, molybdenum, boron, agronomic practices, field trials, yield, plant stress tolerance, plant physiological processes.

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Brovarova O.V. (olbrov@mail.ru)

Use of humic preparations in potato cultivation in the Komi Republic

DOI 10.24412/1029-2551-2025-3-007

The article presents results of research of humic preparations on potato growth and development. Established that optimal dose for achieving the best results was 0.5-1.0% of the drug containing potassium. The use of humic preparations during the growing season contributed to the activation of morphophysiological processes in plants. The leaf area increased 1.5-1.8 times, and the photosynthetic potential increased 1.5 times compared to the control variant. The use of different doses of humic preparations had a positive effect on potato vegetation, which led to a statistically significant increase in tuber weight compared with the control. On the 65th and 85th days, potato yields were 10.8 and 23.1 t/ha, respectively, in the control variant, whereas with the use of humic preparations, these indicators reached 22.4 and 35.6 t/ha, respectively. Thus, the use of humic preparations contributed to a 2.0-fold increase in potato yields.

Keywords: humic substances, peat, fertilizers, productivity, yield.

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Bykova O.A., Tropina N.S., Tkhaganov V.R., Tkhaganov R.R., Morozov A.I. (vilar8@rambler.ru, vilarnii@mail.ru)

Influence of bioregulators of different types and their complex with organomineral fertilizers on inflorescence yield and essential oil content of chamomile pharmacy

DOI 10.24412/1029-2551-2025-3-008

The effect of joint application of retardant and growth regulator, organomineral fertilizers on inflorescence yield and essential oil content was studied. In the phase of the beginning of regrowth, foliar fertilizer treatments with Lignohumate (0.5 l/ha), Normat L (0.3 kg/ha) and EcoFus (1.5 l/ha) were carried out, which promoted the activation of growth and development, increasing the height growth up to 10%, dry matter accumulation by 12-15%, and the number of inflorescences by 9-12%. Further, in the phase of mass budding, treatments with bioregulators Hardy (0.2 l/ha) and Zirkon (0.1 l/ha) allowed increasing the collection of essential oil from 31 to 40% per unit area by increasing its content in the raw material up to 25%. Significant productivity is observed due to the system application of humic fertilizers with Hardy bioregulator (0.2 l/ha), where the excess of control in essential oil content is 24-25%, its collection per hectare – by 37-40%, and compared to the application of only one bioregulator – the collection of essential oil per hectare increases by 12-14%.

Keywords: essential oil, humic fertilizers, yield, Chamomile pharmacy, EcoFus, Hardy, Zircon.

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SOIL PROPERTIES

Simasheva A.O., Azarov V.B., Navolneva E.V. (simasheva_ao@belgau, azarov_vb@belgau, navekavika@gmail.com)

Nutritional regime of typical chernozem under winter wheat depending on treatment methods and fertilizer doses̆

DOI 10.24412/1029-2551-2025-3-009

The paper presents the results of research on the influence of the method of basic tillage and fertilizer doses in winter wheat cultivation in grain-ploughing rotation on the content of alkaline-hydrolysable nitrogen, mobile phosphorus and exchangeable potassium. The research was carried out in the conditions of stationary field experiment Belgorod FASC of the RAS in 2021-2023. It was found that the content of nutrition elements in the soil without fertilizers was higher during ploughing. Application of fertilizers and their combination depending on the method of tillage had a non-single effect on the content of nitrogen, phosphorus and potassium. At minimum tillage the nitrogen content in all variants of fertilizer application increased significantly. The highest content of mobile phosphorus was observed at all studied methods of treatment in the variant with double dose of mineral fertilizer and 16 t/ha manure aftermath. Decrease of mobile potassium content was observed on ploughing at application of mineral fertilizer only and aftermath of manure 8 t/ha. At no-tillage and minimum tillage potassium content increased regardless of the variant of fertilizer application. A strong linear relationship between fertilizer doses and the content of mobile forms of phosphorus and potassium in all studied tillage systems is traced.

Keywords: typical chernozem, fertilizers, tillage, nutrient regime, nitrogen, phosphorus, potassium.

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Demidov V.V., Golovchenko A.V., Gracheva T.A., Yakushev A.V., Nesterkina S.Y., Makarov O.A. (demidov951@yandex.ru, golovchenko.alla@gmail.com, tanyadunaeva12@mail.ru, a_yakushev84@mail.ru, n-soniknest@mail.ru, oa_makarov@mail.ru)

Influence of erosion degree on prokaryotic complex of agro-grey forest soil

DOI 10.24412/1029-2551-2025-3-010

The paper discusses the effect of soil washout on agrochemical and microbiological parameters (abundance, biomass of unicellular and mycelial prokaryotes) in different seasons of the annual cycle. The objects of the study are agro–gray forest cultivated soil of varying degrees of washout (not washed, slightly and medium washed) and gray forest soil under natural tree plantations. The studied soils are located on the slope of the eastern exposure of the drainage basin of the Lyubozha River, a right tributary of the Oka River (Moscow Region, Serpukhov city District). It was found that humus reserves in the 30 cm layer of agro-gray forest soil decreased in the range not washed away (104.1 t/ha) > slightly washed (83 t/ha) > medium washed (67.7 t/ha). The loss of humus reserves in relation to not washed soil amounted to 20% in slightly washed and 35% in medium washed soil. It was shown that the dynamics of the abundance of bacteria in the agro-gray forest soil was more determined by the degree of washout (56% of the total dispersion) than by the season (36%). The abundance of bacteria and actinomycete mycelium decreased in the range: not washed > slightly washed > medium washed. The annual average values of prokaryotic biomass decreased from 76 kg/ha in not washed, to 54 kg/ha in slightly washed and 41 kg/ha in medium washed. Losses of prokaryotic biomass relative to not washed soil amounted to 26% in slightly permeated and 46% in medium washed soil. A high level of correlation was revealed between humus reserves and the content of alkaline hydrolyzable nitrogen on the one hand and the abundance of unicellular and mycelial prokaryotes on the other hand. The content of mobile forms of phosphorus and exchangeable potassium was not a limiting factor for prokaryotic microorganisms.

Keywords: degree of washout, season, agrochemical properties, bacteria, actinomycete mycelium, abundance, biomass.

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Ulanov A.K., Biltuev A.S. (burnish@inbox.ru)

Current state of fertility of land in the Ivolginskaya basin of the Republic of Buryatia

DOI 10.24412/1029-2551-2025-3-011

The current state of fertility of irrigated soils of the Ivolginskaya basin of the Republic of Buryatia was studied using the example of the Khalyutinskaya irrigation system with an area of 4109 hectares. The soil cover of the irrigation area is represented by alluvial marsh, alluvial meadow, hydromorphic solonchak, meadow-chestnut and chestnut soils. Within the irrigation area, 20 contours with different soil varieties were identified. In terms of fertility, chestnut-type soils should be classified as soils of medium fertility and, depending on the severity of the limiting factor, defined as soils with a hard water regime, which, when developed, require a set of measures for moisture accumulation, erosion control and optimization of mineral nutrition of plants. Meadow-chestnut soils should be defined as medium-quality soils requiring surface improvement measures. Alluvial meadow soils, based on a complex of agrochemical properties, should be classified as medium-quality soils requiring improvement of water and air regimes, application of fertilizers, and measures to reduce salinity. Marshy soils are low-quality soils that require melioration measures and cultivation with use as hayfields.

Keywords: irrigation system, soil cover, fertility, agrochemical indicators, salinization.

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PLANT PROTECTION

Shumakov D.A., Laptiev A.B., Kungurceva O.V. (shumakov@iczr.ru, laptiev@iczr.ru)

Improvement of spring barley protection from a complex of leaf and stem diseases

DOI 10.24412/1029-2551-2025-3-012

The article presents the results of studies on spring barley, carried out locally (the Moscow, Voronezh, Volgograd and Leningrad regions) in several regions at once, which are part of three (I, II and III) soil and climatic zones of the country. It was found that the causative agents of helminthosporium leaf spots, primarily net spot, are widespread. In addition, barley plants are also affected by other dangerous diseases, including powdery mildew, scald and dwarf leaf rust. A study was conducted on the effectiveness of the modern three-component fungicide Daisy, SE, which is a domestic development based on an innovative combination of active ingredients consisting of propiconazole, tebuconazole and pyraclostrobin. The drug is designed to combat a complex of leaf and stem diseases of spring barley. The fungicide was studied with single and double application at rates of 0.6 and 0.8 l/ha. The use of this product contributed to the effective protection of the leaves and stems of the crop at a high level. Treatment of barley crops with the fungicide Daisy, SE made it possible to maintain grain yields from 3.1 to 9.6 c/ha over the seasons, depending on the frequency and application rates.

Keywords: barley, leaf diseases, fungicide, active substances, biological efficiency.

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Kotova Z.P., Danilova T.A., Danilov L.G., Tyukalov Yu.A. (zinaida_kotova@mail.ru, biodanlg@mail.ru)

Technological methods of potato cultivation with application of biological means of protection based on metabolic products of symbiotic bacteria of entomopathogenic nematodes

DOI 10.24412/1029-2551-2025-3-013

The possibility of using a nematode-bacterial complex and symbiotic bacteria (Хenorhabdus) was studied as a technological technique of biological protection of potatoes from mushroom infections – ledges, rhizoctoniosis and late blight in the conditions of the Republic of Karelia. As a result of field studies in 2022-2024, it was revealed that tubers processing before planting and foliar spraying in the phase of complete budding of the suspension of symbiotic bacteria X. bovienii symbioniic entomopathogenic nematodes of the type of S. feltiae protense or Fitosporin M reduces the degree of development of symptoms of the disease of ordinary tubers to 1% compared to control with control (13%), contribute to the suppression of rhizoctoniosis on tubers by 50-55%, reduce the spread of late blight on potatoes by 2-10%. It has been established that biological drugs have a positive effect on productivity, increasing the yield of potato tubers by 12-18%.

Keywords: potatoes, entomopathogenic nematodes, Fitosporin M, KI, biological efficiency, harvest of tubers.

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EXPERIMENTAL RESEARCHES

Mironova O.A., Amerkhanov Kh.A., Kirichuk A.A., Karmazin A.P. (kirichuk-aa@rudn.ru, Fumrostov@mail.ru, m2889888@mail.ru, h.amerhanov@yandex.ru)

Influence of long-term storage of fermented feed and its refermentation on quality and safety indicators

DOI 10.24412/1029-2551-2025-3-014

The paper studies changes in feed products obtained by microbiological fermentation during long-term storage and repeated fermentation of different duration. It was found that during storage for three months in the fermented feed, the mass fraction of moisture decreased by 1.4 times, the content of crude fat – by 1.3 times, soluble carbohydrates – by 15 times, starch – by 4.5 times. The level of metabolic energy for cattle fell by 24.1%, for pigs – by 61.3%, for poultry – by 24.0%, for sheep – by 23.8. The content of crude protein increased by 18.4%, the mass fraction of crude fiber increased by 2.2 times, crude ash – by 2.4 times. The content of vitamin B1 increased by 8.0 times, vitamin B6 – by 1.7 times, vitamin B2 – by 19.5%, vitamin B12 – by 26.5%, the iron content during substrate storage increased by 17.0 times. During repeated fermentation, their levels continued to remain high. Re-fermentation of the substrate after storage, regardless of the fermentation time, did not significantly affect the studied parameters. In the fermented substrate, which was stored for three months, the TMC increased by 115.4 times, CFU/g mold fungi – by 320 times, CFU/g yeast – by 133 times; after 36 hours of repeated fermentation, the TMC increased by 169.2 times after 12 hours of repeated fermentation, CFU/g mold fungi – by 145 times; after 24 hours. CFU/g yeast – 166.7 times in relation to the primary fermented product. CFU/g salmonella, anaerobes, coliforms were not found in the studied samples; mycotoxins, pesticides, nitrates and nitrites, GMOs in quantities exceeding the MAC were not detected.

Keywords: fermented feed, storage, quality, safety, Lesnov's starter, repeated microbiological fermentation.

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Beksheneva L.F., Reut A.A. (linden7@rambler.ru, cvetok.79@mail.ru)

Efficiency of organomineral fertilizers on some varieties of iris

DOI 10.24412/1029-2551-2025-3-015

The article presents the results of studies on the influence of amino acid-peptide fertilizers (Italpollina fertilizers – Trainer, Quick-link, Skudo, Tifi) on perennial ornamental plants using the example of varieties of Iris hybrida x hort (Dark Mood, Edith Wolford, New Snow), planting in the South Ural. During the growing season, in the phases of growth, budding and flowering, root and foliar treatments of plants were carried out, as well as their combinations. The use of various experimental schemes contributed to an increase in the length and width of iris leaves (by 8.8-23.1% and 16.1-28.8%, respectively). The variety Dark Mood was the most responsive to the introduction of preparations: 5 morphobiological indicators out of 14 significantly differed from the control. Fertilizers did not affect the size characteristics of the generative organs of irises, which indicates a stable reaction of flowers and peduncles to fertilizing. The use of fertilizers contributed to a decrease in water deficit (by 14.8-65.8%) and an increase in the water-holding capacity of plants (by 19.7-71.4%). Thus, the studied preparations can be considered as growth stimulants and as an effective means for improving the water regime of irises.

Keywords: iris, growth regulator, fertilizer, amino acids, peptides, morphological parameters, water regime, Italpollina.

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Khismatullin M.M., Lukmanov A.A., Erov Yu.V., Khismatullin M.M., Pogodina A.V. (rezi-almet@yandex.ru, agrohim_16_1@mail.ru, erov1950@mail.ru, marselmansurovic@mail.ru)

Technical support of modern irrigation equipment for watering seed crops of spring wheat in soil and climatic conditions of the Republic of Tatarstan

DOI 10.24412/1029-2551-2025-3-016

This paper examines the efficiency of irrigation of seed crops of spring wheat depending on the varietal characteristics of the crop and the design of sprinkler machines, including economic indicators of the production of elite seeds. It has been established that in the conditions of the Republic of Tatarstan, fine-dispersed irrigation with a Kazanka sprinkler machine of the Nikon variety ensures the production of 4.88 t/ha of seeds corresponding to the II quality class with a production profitability of 44%.

Keywords: sprinkler machines, spring wheat, varieties, irrigation, yield and seed quality.

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YOUNG SCIENTISTS RESEARCH

Kucherenko A.V. (scientific supervisor – Dr.Sci., professor O.A. Biryukova) (alkucherenko@bk.ru)

Group composition of copper and manganese compounds of the calcic chernozem during cherry cultivation

DOI 10.24412/1029-2551-2025-3-017

This study investigates the total content and compound speciation of copper and manganese of the calcic chernozem under cherry cultivation in the Rostov region. Results demonstrate an accumulative distribution pattern of both elements within the soil profile, attributed to biogenic processes. Furthermore, significant correlations were observed between Cu and Mn compounds and key physicochemical soil properties. Features of the group composition of Cu and Mn of the calcic chernozem have been established, which must be taken into account when optimizing the mineral nutrition of fruit crops.

Keywords: group composition of microelements, calcic chernozem, copper, manganese, horticultural agrocoenosis.

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Pinaeva A.S. (scientific supervisor – Ph.D. I.V. Elshaeva) (pinaeva95@inbox.ru)

Nickel accumulation by vetch-oat mixture and pasture ryegrass from soddy-podzolic soil under conditions of long-term experiment with sewage sludge

DOI 10.24412/1029-2551-2025-3-018

In the conditions of the field shallow-delta experiment in the Saint-Petersburg SAU n 2021-2023 studies were conducted on the effect of compost from sewage sludge at a dose of 20 t/ha, in combination with mineral fertilizers and manure on the content of gross and mobile forms of nickel in the soil, as well as the accumulation of the trace element by legume-grass and cereal grasses. After application of the studied fertilizers, the nickel content in the sod-weakly podzolic soil and plants did not exceed the maximum permissible concentrations for all three years of the study. The average yield for the variants with fertilizers in 2023 for two cuttings was 163.4 c/ha, significantly different from the control. Legume-cereal and cereal grasses serve as deconcentrators in terms of the accumulation coefficient. Strong accumulation of nickel (IA > 10) was observed in vetch-oat mixture plants and pasture ryegrass in the first year of vegetation. Vigorous accumulation (1 > IA > 10) was observed in cereal grasses in the second year of vegetation. Such accumulation is typical for a group of microelements that are essential elements for plants.

Keywords: nickel, sewage sludge compost, gross and mobile form, accumulation factor, accumulation index.