RU2829354C1 - Method of increasing potato yield - Google Patents

Abstract

FIELD: agriculture.

SUBSTANCE: invention relates to the field of agriculture, namely to a method of soil enrichment during potato cultivation. In the method, an organic substance is used as a fertilizer, nutrients are used in crop rotation and pre-harvest treatment of potato plantations is carried out. Lupine is used as a precursor. Organic fertilizer used is crushed lupine straw with size of up to 7-12 cm in amount of 3 t/ha, which is then uniformly scattered over the field, embedded in the soil with a heavy disk harrow at depth of 10 cm, and fall-ploughed at depth of 20 cm in autumn. Additionally, transverse disking of the field is carried out, and in the second year, in the spring, mineral fertilizers are applied in a dose of N₉₀P₉₀K₁₂₀ to depth of 6-8 cm for presowing cultivation and potatoes are planted in the first decade of May when physical ripeness of soil with density of 50 thousand tubers per 1 ha is achieved.

EFFECT: method ensures increase of soil fertility, potato yield and quality of tubers at return of plant remains of annual lupine bean pod valves to the soil.

2 cl, 2 dwg, 3 tbl, 3 ex

Description

The invention relates to agriculture, namely to a method for enriching soil when cultivating potatoes.

Potato growing is a traditional branch of agriculture, firmly holding second place after grain crops. However, one of the main reasons for the low efficiency of domestic potato growing is Russia's significant lag behind global agro-technological progress.

It is known that in agriculture the most important and basic means of production is soil, which has fertility. Soil fertility is understood as its ability to serve as a habitat for cultivated plants, a source of providing earthly factors of life.

Potato requirements for soil and its fertility are related to its biological characteristics: a relatively poorly developed root system and the formation of stolons of tubers in the soil. The best soils for potatoes are loose soils with good air permeability, low humidity and permeable horizons.

In Russia, the available straw resources significantly exceed the volumes of its actual use, i.e. there is potential for increasing the volumes of its use as a fertilizer without removing it from the field, which is the most environmentally friendly and economically feasible way of utilizing plant waste. By returning plant residues, it is possible to significantly compensate for the removal of nutrients from the soil.

In a number of highly developed agro-industrial countries, in order to increase the productivity of livestock farming and reduce the cost of production, close attention is paid to the leguminous crop - lupine, the grain of which is a component of feed mixtures with a high content of essential amino acids and protein in general (Seraya T.M., Mezentseva E.G. et al. Productivity of narrow-leaved lupine on sod-podzolic sandy loam soil//Soil Science and Agrochemistry. 2011. No. 1 (46). P. 192-201).

Lupine is recommended in biologized crop rotations, often as a predecessor of potatoes, as an environment-improving crop that accumulates nitrogen and improves soil fertility. In addition, lupine forms about 30 c/ha of straw, which is characterized by a narrower nitrogen-to-carbon ratio than cereal straw and can be used as fertilizer without compensating additives (Novikov M.N. Leading crop in the biologization system of agriculture // Agrarian Bulletin of the Upper Volga Region. 2019. No. 3 (28). Pp. 41-47).

Lupine is also used as a green manure. However, there is virtually no experimental data on the impact on soil fertility and crop productivity, on the amount of phytomass and nutritional elements supplied by lupine plant residues remaining in the field after grain harvesting.

Post-harvest plant residues are a direct source of readily available carbon and nitrogen for microbial activity, so their additional supply to the arable layer can significantly affect the number, biomass and activity of the soil microbial community.

A method of cultivating potatoes on irrigated lands is known, which involves tilling the soil, applying organomineral fertilizers, cutting ridges, carried out simultaneously by a chisel working element with inclined racks equipped with moldboards and fertilizer pipes; a mixture of straw, mineral fertilizers and coal ash is used as organomineral fertilizers, mineral potassium and phosphorus fertilizers are applied once - in the fall, and mineral nitrogen fertilizers are applied in the form of ammonium nitrate at the rate of 15 kg / ha 1 t of straw; the ratio of the mixture components - straw, mineral fertilizers and coal ash - is 2.3: 3.3, respectively; the mixture is applied to the soil at the rate of 60 t / ha (Patent RU No. 2354095, A01B 79/02 dated 10.05.2009).

The disadvantages of the described method, despite the declared possibility of obtaining potato tubers of various varieties up to 60 t/ha include low efficiency of using mineral fertilizers applied in large doses of N ₁₈₀ P ₁₄₀ K ₂₇₀ kg active ingredient/ha and organic fertilizers at a rate of 40-60 t/ha, as well as the lack of a method for expanding the diversity of possibilities in the form of chopped straw of annual white lupine with nutrients entering the soil, i.e. the influence of post-harvest residues on the biological state of sod-podzolic soil to stimulate cultivated potatoes.

A method of growing potatoes in a two-field crop rotation is known, which includes placing potatoes on predecessors, cultivating the soil with the incorporation of the root residues of the predecessor, applying mineral fertilizers, cutting ridges, planting in ridges, inter-row cultivation and weed control, pre-harvest removal of tops and harvesting of tubers, in which seed potatoes of early varieties with a vegetation period of 90-105 days are taken for planting, and they are grown in a two-field intensive crop rotation, including: annual grasses - winter rye mown; winter rye - by mowing, potatoes - by fall plowing, and early varieties of winter rye are used as a predecessor to potatoes, carried out on August 10-15 after harvesting annual grasses without additional application of organic fertilizers, while winter rye is harvested in the phase of emerging into a tube for green mass with a high cut of 12-15 cm with the incorporation of the remaining stubble and the root system of rye by plowing to 20-25 cm, to 10-15 cm 3-5 days before planting potatoes in ridges, which is carried out on June 10-15, and potatoes are harvested in September; Pre-harvest removal of tops is carried out using a mechanical chopper and spreading over the field, and after harvesting the potatoes, autumn plowing is carried out (Patent RU No. 2349068, A01B 79/08 dated 20.10.2009).

The disadvantages of the described method of growing potatoes in a two-field crop rotation include the fact that annual grasses, winter rye and the introduction of N ₉₀ P ₉₀ K ₉₀ cannot ensure high and stable potato yields, and there is no way to expand the diversity of possibilities that ensure the optimal choice of the method to establish the size and ratio of alienated plant products (grain) and plant residues of annual lupine returned to the soil, the amount of nutrients entering the soil, the effect of post-harvest residues on the biological state of sod-podzolic soil and potato yields. Lupine is a tall-stemmed legume with a high content of essential amino acids and protein in general.

A method of drip irrigation of early potatoes in the conditions of the Republic of Bashkortostan is known, in which during the potato growing season an irrigation regime of 85-90 and 85-95% of the HB is maintained and the calculated doses of fertilizers are applied for the planned yield of 30 and 40 t/ha of tubers of the early potato variety Red Scarlett (see the article by A.D. Andrianov, D.A. Andrianov. Drip irrigation of potatoes // Melioration and water management. - 2008. - P. 37-39).

The disadvantages of the described method of drip irrigation of the early ripening Red Scarlett variety include low tuber yield (30-40 t/ha) with the potential of the variety being 80-100 t/ha of marketable tubers. The latter is not due to severe meteorological conditions in the Republic of Bashkortostan, but to an incorrect mineral nutrition regime, and there is no way to expand the diversity of possibilities that ensure the establishment of the size and ratio of alienated plant products (grain) and plant residues of annual lupine returned to the soil, the amount of nutrients entering the soil, the effect of post-harvest residues on the biological state of sod-podzolic soil and its yield - lupine, the grain of which is a valuable component of feed mixtures with a high content of essential amino acids and protein in general.

A method for enriching the soil during cultivation of agricultural crops is known, which includes the introduction of organic and mineral fertilizers into the soil. Straw and winter green manure are used as organic fertilizers, with chopped straw in the amount of 5 t/ha being embedded with disc harrows to a depth of 10-12 cm in the fall and winter green manure being sown, which in the spring, when green mass has accumulated to 8 t/ha, is embedded into the soil with disc harrows to a depth of 8-10 cm, and plowing is carried out to a depth of 20-22 cm, and then mineral fertilizers (N ₄₈ P ₄₈ K ₄₈ ) are introduced to a depth of 6-8 cm for pre-sowing cultivation (Patent RU No. 2185047, A01C 21/00 dated 20.07.2002).

The disadvantage of this method is that the application of organic fertilizer in the form of chopped cereal straw in the fall requires compensating nitrogen additives. The role of the proposed lupine used as a green manure fertilizer shows in practice that there are still no experimental data on the effect of post-harvest residues of annual lupine grown for grain on soil fertility and crop productivity, and there is no information on experimental data on the amount of phytomass and nutritional elements with post-harvest residues of lupine, respectively, there is no sufficient information on the chemical and biomass of lupine bean valves. Therefore, unlike the main products of grain crops compared to annual lupine, and therefore the possibility of decomposition of lupine straw by the time of sowing.

A method is known for preparing a soil zone for potato development, which includes cutting ridges, applying fertilizers to the ridge, and then planting potatoes. In this case, the ridges are cut to a lower height than traditional ones, and the potatoes are planted in the main horizon of the treated soil layer, increasing the depth of planting tubers. In addition, fertilizers are applied to the soil in such a way that their maximum content is at a depth of 25 and 30 cm, with this content decreasing towards the soil surface (Patent RU No. 2629281, A01B 79/02, A01C 21/00, A01B 49/06, A01B 13/02, A01B 13/14, A01B 33/06 dated 28.08.2017).

The disadvantage of the known method is that although the ridges are cut to a lower height relative to traditional ones, and the potatoes are planted in the main horizon of the processed soil layer, increasing the depth of planting tubers, however, fertilizers are applied to the soil to a depth of 25-30 cm, therefore fertilizers are poorly used in the initial period of root system development, i.e. in later periods of development, the root system uses nutrients for a short time, since only an insignificant part of the roots comes into contact. Weak development of the root system in the location zone reduces drought resistance of potato plants, and as a result, insufficient yield is observed in the potato growing system, in particular, this applies to the different reaction of the proposed method, where in order to reduce the cost of production is associated with the use of crushed straw of annual lupine, which is a high-stemmed legume crop, with the supply of nutrients to the soil, then in the second year in the spring, mineral fertilizer is applied.

In general, the analysis of the known set of different methods for implementing potato planting material leaves open the question of a more rational use of green lands associated with a further increase in potato yield. At the same time, the study of biological processes in the soil is becoming increasingly relevant, from the point of view of the use of chopped straw of annual lupine for plowing in the fall, and in the spring, the use of small doses of mineral fertilizer on the condition of sod-podzolic soil and potato yield.

A method for growing potatoes is known (taken as a prototype), which includes using a grain crop as a precursor, sown on a layer of perennial grasses, stubble peeling, plowing, cutting ridges in the fall, pre-planting treatment of tubers by heating and sprouting tubers in covered areas, planting (Patent RU No. 2199197, A01B 79/02, A01G 1/00 dated 27.02.2003).

In order to accelerate vegetation, the technological regulations for potato cultivation provide for pre-sowing treatment of planting material of tubers with the biostimulant SIMBINIT-UNIVERSAL in accordance with copper sulfate (CaSO ₄ ) - 0.2 g (1 tablet) and other preparations. Then, sprouted potatoes are planted directly suitable for the conditions of the middle zone or in the conditions of early spring in the first ten days of April. The reference point is the period of complete thawing of the soil. And instead of mineral fertilizers and organic fertilizers - manure to obtain consistently high yields of potatoes, it is recommended to use a complex chlorine-free environmentally friendly organic fertilizer of prolonged action ROOT mixture and (or) similar action ROOT NUTRIENT KP-100, biological environmentally friendly immunostimulants of plant growth.

However, the known method leaves open the question of a simpler and more rational use of biologization techniques in agriculture, which are very relevant and relate to the introduction of legumes into crop rotation, namely the legume crop - lupine, the grain of which is a valuable component of feed mixtures with a high content of essential amino acids and protein. In addition, the role of lupine has been well studied as a green manure fertilizer. However, there are practically no experimental data on the effect of post-harvest residues of annual lupine grown for grain on soil fertility and crop productivity. After harvesting annual lupine, up to 2.3 tons of post-harvest residues (63.4-69.8% of the total above-ground mass) remain per 1 ton of grain, in the structure of which 31-37% are bean valves. Their incorporation into the soil allows returning 32-38% of nitrogen, 39% of phosphorus, 73-74% of potassium from the total removal into the biological cycle. The introduction of post-harvest lupine residues into the arable layer of sod-podzolic sandy loam soil ensures the creation of favorable conditions for the soil microbiome of amylolytic, cellulolytic microorganisms, a decrease in biomass, and an increase in potato yield by 12-14 c/ha.

The technical result is an increase in soil fertility, potato yield and tuber quality when returning to the soil plant residues of straw and bean pods, annual lupine on sod-podzolic soil.

The technical result is achieved by the fact that in the method for increasing the potato yield, organic matter is used as a fertilizer, nutrients in crop rotation and pre-harvest treatment of potato plantings is carried out, lupine is used as a predecessor, while chopped lupine straw up to 7-12 cm in size is used as an organic fertilizer in an amount of 3 t / ha, which is then evenly scattered over the field, embedded in the soil with a heavy disc harrow to a depth of 10 cm, in the fall ploughed under fallowing to a depth of 20 cm, according to the invention, transverse disking of the field is additionally carried out, and in the second year in the spring, mineral fertilizers are applied at a dose of N ₉₀ P ₉₀ K ₁₂₀ to a depth of 6-8 cm under pre-sowing cultivation and potatoes are planted in the first ten days of May upon reaching physical maturity of the soil with a density of 50 thousand tubers per 1 ha.

In addition, soil cultivation is carried out before and after planting potatoes.

The distinctive features of the claimed method are that when increasing the yield of the Scarb potato variety, the precursor is first the introduction of chopped straw and annual lupine bean pods in the fall after harvesting the grain at a dose of 3 t/ha, as an organo-mineral fertilizer.

The straw of white lupine "DEGA" is chopped (7-12 cm) simultaneously with the grain harvesting by the SAMPO-500 combine with a chopper and evenly distributed over the field, embedded in the upper layer to a depth of 10 cm by the BDT-3 disc harrow, then after 2-3 weeks, autumn plowing is carried out by the PLN-3-35 plow to a depth of 20 cm. Then in the second year - in the spring before planting potatoes, cultivation is carried out and mineral fertilizers are applied at a dose of N ₉₀ P ₉₀ K ₁₂₀ , potatoes are planted with a density of 50 thousand tubers per 1 ha by the VSM-4 potato planter to a depth of 6-8 cm.

Thus, it generally affects the agronomic factors of fertility, weed control and soil loosening. Ultimately, green manure fertilizers in the form of annual lupine (straw and bean pods) enrich the soil with organic matter and nutrients (nitrogen, phosphorus, potassium), especially organic ones, which significantly affects all soil regimes. After harvesting lupine, up to 2.3 tons of post-harvest residues (63.4-69.8% of the total above-ground biomass) remain per 1 ton of grain, in the structure of which 31-37% are bean pods. Their incorporation into the soil also allows returning 32-38% of nitrogen, 39% of phosphorus, 73-74% of potassium from the total removal to the biological cycle. Thus, the introduction of post-harvest lupine residues into the arable layer of annual lupine straw on sod-podzolic soil ensures the creation of favorable conditions for the soil microbiome and contributes to an increase in the number of ammonifying amylolytic, cellulolytic microorganisms, a decrease in mineralization and oligotrophy coefficients, an increase in microbial biomass, and an increase in potato yield by 12-14 c/ha.

Thus, the above information indicates that the presented invention has the stated properties and a set of distinctive features of the described method, which ensures the achievement of the specified result.

As a result of the conducted analysis of the state of the art of potato cultivation technology based on biologization of agriculture in the conditions of the Vladimir region of sod-podzolic soil, characterized by features identical to all essential features of the claimed invention, was not found, therefore, the claimed invention meets the condition of "novelty".

An additional search of known solutions showed that the claimed invention is obvious to a specialist from the known state of the art, since new conditions have been selected that provide stimulation of the cultivated plants of a high-yielding variety of potato. Consequently, the claimed invention meets the condition of "inventive step".

To confirm the technical results, experimental field work was carried out to study soil fertility, which is expressed in the humus content and its composition in the following variants: 1. Control (without fertilizers); 2. N ₉₀ P ₉₀ K ₁₂₀ - background; 3. Background + lupine straw 3 t/ha; 4. Lupine straw 3 t/ha.

Thus, in the technological aspect, these are factors of biologization of potato cultivation technology - the use of annual lupine as a green manure fertilizer.

The claimed method takes into account to a greater extent the influence of lupine straw on the microbial community and the influence of plant residues on the biological state of soils, contributes to the improvement of the soil nutritional regime, its ability to serve as a habitat for cultivated plants, a source and mediator in providing earthly factors of life, i.e. biological characteristics of soil culture, new elements of industrialization.

Mineral fertilizers also accelerate the decomposition of livestock remains, which contributes to the formation of humus.

The potato variety "Skarb" was chosen as the object of the study.

Variety - "Skarb" - mid-late variety, resistant to disease, unpretentious in care. Potato Skarb was bred in Belarus. In 2002, the variety was included in the State Register for the North-West and Central regions. Bushes are compact, medium height. Very strong and formed from thick shoots. A little green foliage of a dark color, oval-elongated shape, with smooth edges appears on the stems.

The tubers fully ripen in 80-90 days after emergence. They have an excellent taste, do not darken or boil over when cooked. The skin is light golden, very smooth and even. The eyes are small, evenly spaced and not deep. The tubers are quite large, yellowish, oval-round, even, weighing 150-250 grams. One plant can produce 12 to 18 excellent root crops. The average weight of one tuber reaches 200 grams. One hectare yields 50-60 tons of harvest. Tender, uniform, bright yellow. The starch content is no more than 17%. It is not planted deeply. It is drought-resistant.

The yield indicators will be specifically shown to us below based on research on sod-podzolic soil in the Vladimir region for 2022-2023.

Example 1. As noted above, the field experiment design included four options. For growing potatoes, the predecessor was annual lupine as a green manure. Grain-row crop rotation: winter wheat-lupine-potato-barley-annual. The experiment design includes options with the application of mineral fertilizers annually before sowing crops, straw of grain and leguminous crops of the crop rotation (winter wheat, lupine and barley, in the fall after harvesting at 3 t/ha, as well as a combination of straw and mineral fertilizers). The studies were carried out in agrocenoses of white lupine (Lupinus dlbus.L), potato variety "Skarb".

Example 2. In the control plots in the fall, when harvesting the grain legume predecessor, the straw was chopped (to 7-12 cm) simultaneously with the grain harvesting using a SAMIPO-500 combine with a chopper and evenly distributed over the experimental plots, the soil was cultivated to a depth of 20 cm using a BDT-3 heavy disc harrow, then 2-3 weeks later in the fall, plowing was carried out to a depth of 20 cm using a PLN-3-35 plow, followed by transverse disking of the field.

Example 3. Differs from example 2 in that in the spring, mineral fertilizers N ₉₀ P ₉₀ K ₁₂₀ are added to the soil for pre-sowing cultivation to a depth of 6-8 cm, then potatoes are planted. At the same time, with the Background + lupine straw 3 t / ha option, the average potato yield for 2022-2023 was 183 c / ha compared to the control (see Table 3).

The research was carried out in a field experiment laid out in 2022-2023 on the experimental field of the All-Russian Research Institute of Organic Fertilizers and Peat - a branch of the Upper Volga Federal Agricultural Research Center. The soil is sod-podzolic sandy loam, underlain by moraine loam.

The soil for the experiments was characterized by the following agrochemical parameters: pH _RCl - 4.6-4.9; mobile phosphorus - 0.52-0.67%; exchangeable potassium - 83-99 mg/kg of soil; C _org - 0.52-0.67%.

Agricultural technology complied with zonal recommendations, which include the Vladimir region.

The experiments were repeated four times. The experiment was carried out using the method of randomized repetitions. The total area of the plot was 42 m ² .

The method of accounting is continuous, from the entire accounting area of the plot. The method of fractional accounting was used to determine the biological yield of potatoes and its structure.

The statistical error was carried out using the method of dispersion analysis according to B.A. Dospekhov (1985) using a computer.

The calculation of the humus balance in the soil under potatoes was carried out according to the method proposed by A.M. Lykov (Popov P.D. et al. 1987).

The mass and structure of the above-ground lupine biomass (grain, straw, bean pods) were measured in test sheaves collected immediately before harvesting.

The content of essential nutritional elements in plant samples was determined: nitrogen, phosphorus, potassium according to the relevant GOSTs.

Soil samples for analysis were collected using a rod auger (0-20 cm), and mixed samples were prepared from 20-30 individual samples from each plot (42 ^m2 ).

The biological state of the soil was assessed by the following indicators: the number of microorganisms belonging to different ecological groups was taken into account on solid nutrient media: ammonifying on meat-peptone agar (MPA); amylolytic - on starch-ammonia agar (SAA); cellulolytic - on Gechinson's medium; the content of microbial biomass ( _Cmic ) was determined by the rehydration-extraction method. Microbiological analyses were performed in fresh samples with data recalculation for dry soil.

Oligotrophicity coefficients (Colitis) were calculated as the ratio of the number of microorganisms grown on CAA to the number of microorganisms recorded by the MPA culture.

In the experiment, the introduction of mineral fertilizers and organic fertilizers affects not only the agrochemical factors of fertility. Fertilizers, especially organic ones, significantly affect all soil regimes, changing the habitat of plants, which affects their growth and development, and ultimately - the size of the harvest.

The results of the conducted studies of the total above-ground biomass of lupine (grain, straw-stubble, bean pods) varied from 30.1 c/ha against the background of mineral fertilizers to 36.9 c/ha with long-term application of straw without mineral fertilizers. In the structure of the above-ground biomass of lupine, the share of the main commercial product (grain) was 30-37%, straw and stubble - 31-37%, bean pods - 31-36% (Fig. 1).

The ratio of straw to grain of the white lupine variety "Dega" was 1.37. The coefficient of conversion of lupine grain into by-products at a yield of less than 20 c/ha is from 0.8 to 1.21 tons. Taking into account the weight of the bean pods, this ratio increased significantly to 1.73-2.31 tons.

Thus, it was experimentally established that a crop such as annual lupine makes up to 2.31 tons of plant residues per 1 ton of grain in total (straw, stubble, bean pods).

An analysis of the chemical composition of lupine in the experiment showed that the grain had the highest nitrogen content, from 5.61 to 5.98%; post-harvest residues contained from 1.87 to 2.99% (in straw) and 0.79-0.99% nitrogen (in bean sections).

Post-harvest residues were characterized by a high potassium content, which was 1.03-1.61% in straw and 1.24-1.43% in bean pods. The total removal of nutrients with the lupine harvest was: nitrogen - 78.1-117.7; phosphorus - 14.0-20; potassium - 34.9-43.6 kg/ha.

Table 1 shows the content and removal of nutrients by the lupine crop.

With lupine straw, 19.4-32.6 kg of nitrogen; 2.7-3.6 phosphorus; 10.7-16.4 kg of potassium entered the soil. If we additionally take into account the lupine bean valves in the composition of by-products, the mass of which was equal to the mass of straw, then the total return of nutrients to the soil was 29-45 kg of nitrogen; 5.4-8.2 kg of phosphorus; 25.7-32 kg of potassium, or, accordingly, 32-38; 39; 73-74% of the total mowing.

Post-harvest plant residues are a direct source of biologically available carbohydrate and nitrogen for microbial activity, so their additional supply to the arable layer can significantly affect the amount of biomass and activity of soil microbiosis.

Management methods and agricultural technologies that ensure high rates of exogenous carbon input into the soil, including through the return of post-harvest plant residues, which are a trophic and energy source, “hot spots” for the microbial population, create conditions for the preservation and growth of microbial biomass.

The conducted studies have established that leaving and incorporating into the soil post-harvest residues of agricultural crops, which are a source of biologically active organic matter and nutrients for soil microflora, helps to optimize the biological state of soils.

Compared to cereals, leguminous crops are characterized by a higher C:N ratio in straw, which is in the range of 40-55, which is more favorable for soil microorganisms.

In the soil, organic matter and nutrients are distributed heterogeneously, and microorganisms with different requirements for food and energy sources coexist. Thus, it depends on the reserves of readily available organic matter.

The conducted studies showed that the inclusion in the crop rotation of the intermediate crop of annual lupine, grown after harvesting winter wheat, with the addition of lupine straw in the variant without mineral fertilizers created favorable conditions for the growth of soil microorganisms, which are mostly ammonifying and cellulose-decomposing, and was accompanied by an increase in the number of these groups in relation to the control (without fertilizer) by 1.34 to 1.41 times, respectively.

Table 2 shows the number of microorganisms on sod-podzolic soil (0-20 cm layer), average for 2022-2023.

The data in Table 2 indicate that in the years of research conducted, the variant with the introduction of lupine straw against the background of mineral fertilizers was characterized by maximum values, and most significantly (by 1.59 times). The number of cellulolytic microorganisms also increased.

It should be noted that the introduction of fresh organic matter into the soil contributed to an increase in the number (they were incorporated into the top 10 cm of soil with a disc harrow, then after 2-3 weeks they were plowed with a PLN-3-35 plow during autumn plowing to a depth of 20 cm), not only of the zymogenic group, but also of the oligotrophic group.

The studies on mineralization coefficients (K _m ) were the highest 2.3 and 2.19 in the variants in comparison with the control (without fertilizers) and in comparison with NPK depleted in fresh organic matter (Table 2).

In variants with the incorporation of lupine straw, this indicator significantly decreased to 1.35 due to the higher amount of ammonium fixer, which indicates a change in the direction of microbiological processes towards humus synthesis.

It has been experimentally proven that 80-90% of soil humic substances consist of the remains of microbial cells and products of microbial metabolism.

Analysis of the content of microbial carbon ( _Cmic ) in the soil of the experiment showed that the minimum value of this indicator for two sampling periods (seedlings and after potato harvesting) - 378-280 mg/kg of soil - was characteristic of the control variant (without fertilizers).

When applying mineral fertilizers, the content of _Cmic increased by 61-78 mg/kg (16-28%), and when adding lupine straw in combination with mineral fertilizers by 139-157 mg/kg (37-56%).

The introduction of lupine straw without the addition of mineral fertilizers was accompanied by an increase in the content of microbial biomass in the soil by 71-50 mg/kg (19-18%) (Fig. 2).

The studied efficiency variations for different climatic conditions and soil types show that the results obtained may differ from each other regarding the effect of straw on crop yield.

The results of the research experiments showed that the yield of potatoes without fertilizers was 105 c/ha, the increase from mineral fertilizers was +54 c/ha.

Table 3 shows the average potato yield for 2022-2023.

Studies have shown that the incorporation of post-harvest residues of the grain legume predecessor (lupine) ensures the return of 70% of the total removal of nutrients to the soil, and contributes to an increase in potato yield by 24 c/ha against the background of mineral fertilizers and by 12 c/ha in relation to the control (without fertilizers).

In addition, after harvesting annual lupine, up to 2.3 tons of post-harvest residues (63.4-69.8% of the total underground biomass) remain per 1 ton of grain, in the structure of which 31-37% are bean valves. Their incorporation into the soil also allows returning 32-38% of nitrogen, 39% of phosphorus, 73-74% of potassium from the total removal to the biological cycle.

Thus, for the described four variants of experiments on cultivation of the Dega lupine potato variety in crop rotation, it is advisable to use the introduction of post-harvest lupine residues into the arable layer of sod-podzolic sandy loam soil and the creation of favorable conditions for soil microbiosis, which contributes to an increase in the number of ammonifying, amipolytic, cellulolytic microorganisms, a decrease in the mineralization and oligotrophy coefficients, an increase in microbial biomass, an increase in potato yield by 12-24 c/ha, in addition, fertilizers improve soil fertility and increase the yield of environmentally safe crops.

The developed method is universal in its application, as it takes into account important, but unstable indicators: the content of nutrients in the straw and its volume (yield). Each year, the straw contains different amounts of carbon and nitrogen, so the doses of compensatory nitrogen can only be determined based on its chemical analysis. The use of the claimed method will significantly reduce the costs of applying mineral fertilizers, while the arable soil layer is guaranteed to be enriched with organic matter (lupine straw) and, as a result, the yield of agricultural crops increases.

Claims (2)

1. A method for increasing potato yields, which involves using organic matter as a fertilizer, nutrients in crop rotation and performing pre-harvest treatment of potato plantings, using lupine as a predecessor, while chopped lupine straw up to 7-12 cm in size in an amount of 3 t/ha is used as an organic fertilizer, which is then evenly scattered over the field, embedded in the soil with a heavy disc harrow to a depth of 10 cm, ploughed under fall plowing to a depth of 20 cm in the fall, characterized in that transverse disking of the field is additionally carried out, and in the second year in the spring, mineral fertilizers are applied at a dose of N ₉₀ P ₉₀ K ₁₂₀ to a depth of 6-8 cm under pre-sowing cultivation and potatoes are planted in the first ten days of May upon reaching physical maturity of the soil with a density of 50 thousand tubers per 1 ha. 2. The method according to paragraph 1, characterized in that the soil is treated before and after planting potatoes.