№ 6 (2024)

The paper considers the issue of scientifically based determination of the need for mineral fertilizers to obtain various gross grain harvest in the near future. In contrast to the previously developed principles for determining the need for mineral fertilizers, a different approach is outlined, which is based on calculations not for the whole country, but for Federal Districts, since their natural and climatic conditions are very diverse. This made it possible to take into account the variability of the calculated data affecting the yield of grain crops and the effectiveness of the use of mineral fertilizers for them. First of all, this applies to the soil cover and agrochemical properties of soils. According to the data obtained, the yield of winter wheat obtained without the use of fertilizers varied from 23.2 to 34.1 c/ha, and the increase in N60 was from 11.4 to 2.2 c/ha. A more significant increase in yield was established during the transition of soils according to the degree of agrochemical cultivation from low to increased to high. The yield of winter wheat on sod-podzolic soil increases 5 times and amounts to 36.7 kg/ha. Similar data were obtained on other types of soils. The need for mineral fertilizers to produce 145–150 million tons of grain is estimated at 5.4 million tons, for 170–175 million tons – at 8.4 million tons.

In the field experiment, the effect of binary sideral sunflower mixtures on the bulk mass, structural coefficient and degree of aggregation of arable and sub-arable horizons of typical heavy loamy chernozem was studied. It is shown that the mixing of crops in sideral agricultural communities in most cases led to an increase in the yield of subsequent grain crops and an improvement in the considered agrophysical properties of chernozem. A decrease in bulk weight, an increase in the coefficient of structurality and the degree of aggregation in both the arable and sub-arable horizons under all mixed agricultural communities were more effective compared to the same horizons under the variants with clean crops. The most significant was the improvement of agrophysical properties in soils under the agricultural communities of soy + sunflower and payza + sunflower. The ability of mixed sideral agricultural communities to effectively reduce the bulk mass makes it possible to reduce it on over-compacted soils, thereby improving the quality of these soils.

In long-term field experience on strongly acidic, poorly cultivated sod-podzolic soil, high efficiency of phosphorus fertilizers combined with magnesium and liming in the cultivation of winter wheat of the Moskovskaya 56 variety was revealed. Under these conditions, the content of nitrogen, phosphorus and magnesium in plants in the flowering phase increased. Improving the mineral nutrition of plants in this case provided the highest yield (75.3 c/ha), exceeding the background level of nitrogen-potassium fertilizers by 2.7 times, the payback of mineral fertilizers (NPK) increased by 2.5 times, reaching 16.7 kg/kg. The use of phosphorus fertilizers on highly acidic soil increased yields by 65% at 27.5 c/ha against the background of nitrogen-potassium fertilizers. On calcified soil with a slightly acidic reaction of the medium, the yield from the use of phosphorus fertilizers increased by 19% compared to the background of 58.1 kg/ha. Yield increases when using magnesium fertilizers against the background of full fertilizer (NPK) decreased as soil acidity decreased and were significant: on medium acidic soil – 4.9 and slightly acidic – 6.1 c/ha. At the maximum yield of winter wheat, due to the use of phosphorus and magnesium fertilizers and a decrease in the acidity of sod-podzolic soil, the removal of nutrients by the winter wheat harvest increased: nitrogen – by 3.5, phosphorus – 3.7, potassium and magnesium – 3 times.

The soils of the Komi Republic are characterized as sod-podzolic. It is known that agricultural cultivation of such soils requires the introduction of various mineral and organic fertilizers, liming, deepening of the arable layer, and erosion control. The soils of the region are depleted of potassium, part of which is carried out by agricultural crops, therefore potash fertilizers, where potassium is in an affordable form, are among the most in demand in agriculture. This paper presents the results of a study of the material composition and textural characteristics of analcime-containing siltstones, potassium alkaline syenites and bark ash and their possible use as potash additives to improve potato productivity.

In the field in 2014–2020, three-component herbicides of betanal generics were tested against juvenile dicotyledonous weeds in sugar beet crops to compare with the effectiveness of the use of the original herbicide Betanal Expert of (BEOF) at application rate of 1.0 l/ha. It is shown that the stability of dilute emulsions of generic betanals depended on the characteristics of the structure and dispersion of working solutions, the ability to crystallize active substances, and reactions to various environmental conditions. The BEOF herbicide in the application rate of 1.0 l/ha differed from generic betanals in the same application rate by a higher effect on weeds. The weeds that formed 2 real leaves showed phase resistance to generic betanals more noticeably. The effectiveness of BEOF on weeds in the cotyledon phase was 6–8% higher than that of generics, and 18% higher when treating weeds in the phase of 2 real leaves. It was found that in the temperature range of 19–22°C, the efficiency of generic betanals was closest to the efficiency of the original BEOF. To stabilize the generic betanals efficacy on weeds with the original BEOF 1.0 l/ha, their application rate was increased by 15–20%. A mixture of generic betanals with the insurance herbicides Mitron and Caribou, applied 3 times in the recommended application rates in accordance with the phase of development of sugar beet, provided high purity of sowing and crop yield at the level of the control group with manual weeding. Herbicides, in addition to broad-leaved dicotyledonous weeds, effectively suppressed young plants of aspens and field bindweed. The insurance herbicides Mitron and Caribou offset the disadvantages of generic betanals when used together in the fight against weeds in sugar beet crops.

In modern agriculture in the Southern Urals, an important agronomic technique is to counteract drought. Of particular importance in increasing the feed base is the cultivation of maize for silage, which ensures maximum yields in extreme conditions. The aim of the study was to determine the potential possibilities of increasing the yield of green mass of maize for silage under the influence of temperature stress in conjunction with the prolonged action of mineral fertilizers and precursors in arid conditions. The study was carried out in the central zone of the Orenburg region from 1993 to 2022 on a stationary site with the southern carbonate heavy loamy chernozem soils with a humus content of 3.2–4.0%. The experiment was carried out with and without mineral fertilizers. The content of nitrate nitrogen in the soil was determined by the ionometric method of Tyurin, mobile phosphorus – by Machigin, exchangeable potassium – by Maslova. A thermostatic-weight method was used to determine soil moisture. On average, over 30 years of research, when cultivating maize for silage in a 6-field crop rotation, an increase in yield was noted with the use of mineral fertilizers from 0.23 to 0.84 t/ha. The annual application of mineral fertilizers in permanent sowing of maize provided an increase in the yield of green mass of 2.51 t/ha. In years with severe aridity, the yield of leaf-stem mass on a fertilized background decreased by an average of 1.61 t/ha. In very dry years, maize plants consumed less nitrate nitrogen (by 2 or more times) than in years with different humidity, but at the same time, potassium consumption increased.

Active cultures of hydrocarbon-decomposing microorganisms from soils of various functional zones of Baku were screened. It was shown that 15 cultures of hydrocarbon-decomposing microorganisms isolated as a result of continuous screening belonged to the genera Rhodococcus, Pseudomonas, Bacillus, Mycobacterium, Actinomyces, Arthrobacter, Micrococcus and were able to use various hydrocarbons (crude oil, paraffin and aromatic hydrocarbons and petroleum products) as the only source of carbon and energy. According to the degree of decomposition, petroleum hydrocarbons were ranked in the series: a mixture of paraffins > petroleum products > aromatic hydrocarbons > crude oil, while the most active strains of microorganisms were isolated from the soils of the industrial and transport zones of Baku, compared with the soils of the recreational zone. The isolated active strains can be considered promising for the creation of biological products to increase soil resistance to pollutants and activate the processes of self-purification of already contaminated soils.

Taking into account the huge amount of data accumulated in recent years on greenhouse gas emissions (primarily CO₂, methane, or greenhouse gases (GHGs)), it is possible to consider the problem of energy efficiency (carbon dioxide emissions occur primarily during fuel combustion, as well as methane and CO₂ as precursors for nitrogen fertilizers) in the chain from the production of fertilizers to their logistics, application, production and waste disposal. At the same time, GHGs emissions can be considered as a measure of energy efficiency in assessing the life cycle of mineral fertilizers. Relevant examples are provided in the review.