RU2774903C1 - Method for cultivating rice on agricultural land not related to rice irrigation systems on underground drip irrigation under mulching film - Google Patents

Abstract

FIELD: agriculture.

SUBSTANCE: invention relates to the field of agriculture, in particular to the cultivation of rice. The method includes growing rice on drip irrigation under a plastic film, preparing seeds, soil and seedlings, controlling irrigation of rice through a drip irrigation system and applying fertilizers. Rice is cultivated on the lands of the irrigated rice fund with underground drip irrigation under plastic and/or biodegradable perforated film. Previously, in the first year of rice cultivation in autumn, after harvesting the predecessor, the main tillage is carried out once to a depth of 0.18-0.22 m, loosening with chisels to a depth of 14-16 cm. Disk is carried out with incorporation of organic fertilizers to a depth of 0.10-0.12 m with an application rate of 40-50 tons per 1 ha of manure or green manure. In the spring of the first year, the laying of the main line and underground hoses and/or drip irrigation tapes is carried out to a depth not higher than the middle of the root system of rice crop rotation crops and the depth of tillage. The step between the water outlets of the underground hose and/or drip irrigation tape is 20 cm, with the diameter and wall thickness of the drip hose and/or tape being 16 mm and 0.9 mm, respectively. The water outflow of the drip hose and/or tape in l/h per 1 m is taken from the condition of providing the required moisture in a given soil layer for crops of rice crop rotation. The distance between the drip hoses and/or tapes is 56 cm. The annual spring-autumn technological cycle of work is carried out, including: harrowing with toothed harrows in two tracks to a depth of 0.08 m, leveling and rolling the soil surface; preparation of rice seeds, including their treatment against seed infection and a single pre-sowing treatment with a growth regulator. Pre-planting irrigation before planting rice seedlings is carried out with a norm that provides soil moisture of 90% of the lowest moisture capacity in a layer of 0.6 m, and the soil surface is treated with soil herbicides. A perforated mulching film is laid on the soil surface, between the strips of which technological passages and passages are made, which are covered with non-woven geosynthetic material. The width of the strips of perforated mulching film and the distance between its strips depends on the technical characteristics of the machinery used for the cultivation of rice and associated crops of the rice crop rotation; at the same time, the condition of soil moistening in the root layer is observed with one underground drip hose and/or a tape of two rows of perforations on the mulch film, in which rice seedlings are planted. The diameter of the perforation is equal to the diameter of a peat pot with a nutrient substrate in which 1 to 4 rice plants are grown, located at a distance of 10 cm from the axis of laying the underground hose and/or drip irrigation tape and 20 cm in a row and between adjacent perforations. Rice seedlings are planted in the perforation of a mulching film in the phase of 6-7 leaves with a green color, a well-developed root system and not infected with pests and diseases, which is sprayed with biologically active substances 1-2 days before planting in open ground. After planting rice seedlings, it is irrigated through an underground drip irrigation system throughout the growing season with the frequency and rate of irrigation, depending on compliance with the condition for ensuring a constant soil moisture of 80% of the lowest moisture capacity in a layer of 0.4 m. Mineral fertilizers are applied in the amount of 25% of the full rate of mineral fertilizers with two equal rates of N₂₀P₁₀K₅ in kg of r.a./ha in the phase of 8-9 leaves after full establishment and in the tillering phase by fertigation through an underground drip irrigation system. Rice plants are treated with pesticides in the tillering phase, with biologically active substances at the end of the tillering phase before the start of booting, twice with fungicides in the booting phase and again after 20-25 days, with insecticides during the growing season when pests exceed the economic threshold of harmfulness. After ripening, the rice is harvested. Before planting the accompanying crops of the rice crop rotation, pre-planting irrigation is carried out through an underground drip irrigation system with simultaneous application of mineral fertilizers, seedlings are planted and/or sowing of the accompanying crops of the rice crop rotation, followed by their treatment with pesticides, fungicides and insecticides. Irrigation of crops of rice crop rotation is carried out through an underground drip irrigation system during the growing season. After the maturation of the accompanying crops of the rice crop rotation, they are harvested, after which a mulching perforated film is collected from the soil surface. If a biodegradable mulching film is used, it is left on the soil surface. Deep loosening is carried out to a depth of 0.14-0.16 m, disking with incorporation of organic fertilizers to a depth of 0.10-0.12 m with an application rate of 40-50 tons per 1 ha of manure or green manure, after which the annual spring-autumn technological the cycle of work is repeated.

EFFECT: method provides for an increase in the productivity and quality of biometric indicators of rice crops, an improvement in the reclamation state of soils, a decrease in the irrigation rate and a decrease in the labor intensity of rice production.

1 cl, 6 dwg, 4 tbl, 1 ex

Description

The invention relates to the field of agriculture, in particular to rice growing.

A known method of growing plants (US Pat. SU No. 1079212 A01G 13.02, 19.03.1983), including spreading a strip of film over the planted plants (the width of the strip depends on the size of the plants being covered and should be approximately three times the height of the plant), cruciform cuts are made in the film directly above plants, through the incisions, the aerial part of the plants is extracted to the outside. Then, some heavy objects are laid out on the film between the plants (to press the film to the soil and prevent it from moving in strong winds), after which both edges of the film rise up and are fastened together above the plants. It turns out a shelter like a tunnel, in which the soil is isolated from the plants with a film, which is also a mulch.

The disadvantages of this method are the low efficiency of rice cultivation due to the high labor intensity of production, high financial costs, lack of irrigation.

A known method of cultivating cotton under a film (agrotechnology) (US Pat. RU No. 2637729, A01B 79.02, 06/05/2015), including spreading the film on the soil, sowing seeds through the holes made in the film, into the nest with simultaneous sealing the edges of the film with soil, cutting irrigation furrows and mulching. In the method, during the sealing of the edges of the film, it is prevented from mechanical cuts and falling asleep with earth, and mulching is carried out after laying the seeds directly into the nest with the mulch covering the holes of the film, which is not removed and removed together with the grown cotton bush.

The disadvantages of this method are large volumes of planning and earthworks for cutting irrigation furrows, high irrigation water consumption when irrigating rice along the furrows, the use of drainage systems, including drainage pumps. In addition, the cultivation of the plant with furrow irrigation leads to slitization processes, which in turn leads to a loss of soil structure and degradation, as well as a decrease in the ameliorative state of soils, waterlogging and the risk of secondary salinization processes due to the rise in groundwater levels. The implementation of this method requires large financial costs and labor resources.

A known method of growing rice seedlings on periodic irrigation, including the technology of growing rice seedlings in a phytotron in nutrient pots, as a substrate, a mixture of various components is used: highly fertile field land, soddy land, humus, high-moor peat, coarse sand with the addition of mineral fertilizers by quantity and the ratio taking into account the need for nitrogen nutrition of rice during the initial growth and development of rice seedlings and the humus content in the substrate is not lower than 40%, the density is less than unity, the porosity is 60-90%, the air content is not lower than 10% while maintaining the optimum temperature when growing rice seedlings in sunny weather during the day they maintain 20-24 ° С, in cloudy weather - 16-18 ° С, at night - 15-16 ° С, optimal pre-irrigation humidity - at the level of 55-65%, relative air humidity - 60-70%, lighting control with the help of fluorescent lamps with their shutdown at night, in addition, seedlings in the phase of 2-3 leaves were fed with nitrogen 1 time no-phosphorus fertilizers in dissolved form, which met the requirements for growing rice seedlings and the technology for growing rice on an experimental field: basic tillage to a depth of 0.20-0.25 m; loosening to a depth of 0.16-0.18 m; field alignment; harrowing to a depth of 0.16-0.18 m; growing rice seedlings; pre-sowing basic application of mineral fertilizers in the amount of 25% of the NPK norm, spraying the soil with a herbicide (against annual cereals) after loosening; spraying with a biologically active substance 2 days before planting seedlings; planting seedlings in open ground S check 1.2 m (length 1.2 m, width - 1.0 m) plants are arranged in 4 rows, between rows 20 cm, between plants 20 cm; irrigation of rice using the “intermittent flooding” technology, namely, simultaneously with the planting of seedlings, water was supplied until the seedlings were flooded by 5-7 cm, then after the seedlings were fully established with moisturizing irrigation for short-term aeration of the upper soil layer, water was supplied until flooding by 7-10 cm to the onset of the tillering phase and the appearance of the 8-10th leaf; application of mineral fertilizers (basal top dressing) in the amount of 50% of the norm N, 25% NH ₄ NO ₃ , 10% P ₂ O ₅ , 50% K ₂ SO ₄ after full survival, the tillering phase and during the budding period; treatment with insecticides for prevention (thrips, leech, aphids) in the tillering phase - exit into the tube; treatment with fungicides for prophylaxis in the tube entry phase; removal of weeds by hand during the growing season; harvesting (L.P. Ionova, N.D. Smashevsky, A.S. Babakova Adaptation of Russian and Iranian varieties of rice when grown by seedlings and periodic irrigation in arid zone conditions // Bulletin of the Altai State Agrarian University No. 10 (156), 2017).

The disadvantages of this method are a high irrigation rate compared to drip irrigation, high weed infestation of rice paddies due to the absence of a mulch film, which reduces the yield and quality of the resulting grain, requires additional financial costs and labor resources for the implementation of this method and is the reason for the high cost and low profitability of rice production. The known method cannot be recommended for rice irrigation systems of the Krasnodar Territory due to the low-fertility heavy merged chernozems of the Abinsk region of the Krasnodar Territory. Performed in a known way, the main tillage to a depth of 0.20-0.25 m on heavy drained soils of the rice irrigation system will not be effective for filtering water from rice fields and creating optimal conditions for oxidative processes in the autumn-spring period. The loosening carried out in the autumn to a depth of 0.16-0.18 m is also insufficient to prevent the soil from drying out after deep plowing and to activate the soil's respiratory activity. The technology described in the method for growing rice seedlings in a phytotron in nutrient pots is ineffective for the soil and climatic conditions of the Abinsk region of the Krasnodar Territory and can lead to both its low survival rate after planting and the mass death of seedlings.

A known method of rice cultivation on drip irrigation, including the use of rice agricultural technology recommended by the All-Russian Research Institute of Rice for flooded rice and VNIIOZ for the cultivation of rice on soil not saturated with water, treatment with soil herbicides after sowing rice, spraying with herbicides of contact action in the phase of 2-3 leaves to combat monocots and dicotyledonous weeds, an irrigation system consisting of a drip line through which water is supplied through a dripper with a flow rate of 1.8 l / h, and the distance between water outlets is -0.33 m, humidifiers - 0.6 m; maintenance of soil moisture according to the following variants of the soil water regime: 1. maintaining moisture in the active (0.6 m) soil layer not lower than 80% of the lowest moisture capacity during the entire growing season of rice, 2. the same as in variant 1 until the end of the phase tillering in a layer of 0.4 m, and from the budding phase to the full ripeness of the grain - 0.6 m, 3. the water regime of the soil before the beginning of the wax ripeness of the grain according to option 2, followed by a decrease in the phase of the beginning of wax ripeness of pre-irrigation moisture to 70% of the lowest moisture capacity, 4. the water regime of the soil in a layer of 0.6 m was regulated according to the scheme: 70-80-70% of the lowest moisture capacity (70% of the lowest moisture capacity from sowing to the beginning of tillering and from the end of milk to full ripeness of the grain; 80% of the lowest moisture capacity - from tillering to the end of milky ripeness); fertilization according to 3 variants of doses calculated to obtain 5 (N ₁₀₉ R ₆₂ K ₇₅ ), 6 (N ₁₃₁ R ₇₄ K ₉₀ ) and 7 (N ₁₅₇ R ₉₀ K108) tons from 1 ha of grain (N.N. Dubenok, I.P. Kruzhilin, N.M. Abdu, M.A. Ganiev, K.A. Rodin Productivity of dry rice under drip irrigation // Izvestiya TSHA, Issue 6, 2015, pp. 92-99.; Kruzhilin, M.A. Ganiev, K.A. Rodin, A.B. Nevezhina Substantiation of predecessors and sowing rates to obtain the planned rice yield under drip irrigation // Proceedings of the Nizhnevolzhsky AgroUniversity Complex: Science and Higher Professional Education, No. 4 (48) , 2017, pp. 77-84.)

The disadvantages of this method are the high infestation of rice fields with weeds due to the lack of a mulching film, the low efficiency of rice production in the conditions of the reclamation and water management complex of the Abinsky district of the Krasnodar Territory, which is due to different soil and climatic conditions of rice cultivation in the Volgograd region and the Krasnodar Territory. In contrast to the light chestnut soils of the Federal State Unitary Enterprise “Irrigated”, Volgograd, on heavy merged chernozems of the Abinsky district of the Krasnodar Territory, the distance between water outlets - 0.33 m and between drip tapes - 0.6 m will be too large to ensure a uniform distribution of the humidification circuit to a given depth, which will lead to overmoistening of the upper layer and underwetting of the lower boundary of the wetted contour. The doses of mineral fertilizers used in the method are ineffective on the initially low-fertile confluent chernozems of the Abinsk region of the Krasnodar Territory.

Known methods of growing rice on drip irrigation under plastic film (Method of drip irrigation under plastic film for rice cropping WO/2015/095989, A01G 22/22, 07/02/2015; Method of drip irrigation under plastic film for rice cropping CN 103733930, A01G 16/00, 04/23/2014 Method for rice cultivation via drip irrigation under plastic film IN 3119/MUMNP/2015, A01G 16/00, 06/03/2016; /02, 02.06.2016; Method of drip irrigation under plastic film for rice cropping PH 1/2015/502551, A01G 25/02, 02.22.2016), including the cultivation of rice under plastic film through drip irrigation with an irrigation rate of 10500-12000 m ³ /hm ² during the entire growing season of rice, repeated irrigation 38-45 times during the entire growing season of rice, the irrigation period is 3-4 days, and 1-2 days during the peak crop water consumption season; seed preparation, soil preparation, including weed control by plowing to a depth of 15-20 cm, rolling the soil and spraying with mixed herbicides before sowing and 15-25 days after planting, sowing rice with a planting density of 33300-36000 holes / mu with a preference of 33300 holes/mu or 30500-32600 holes/mu, with a preference of 30500 holes/mu, at a density of 33300-36000 holes/mu the film width is 215-225 cm, with a preference of 220 cm, with a pitch between outlets from 9 to 10 cm, planting width 235-245 cm, with a preference of 240 cm, as the best irrigation configuration is taken under 1 film, 3 tubes, 12 rows: 13 cm + 24 cm + 13 cm + 20 cm + 13 cm + 24. cm + 13 cm + 20 cm + 13 cm + 24 cm + 13 cm + 50 cm, three drip tapes evenly distributed between 12 rows of rice, at a planting density of 30500-32600 holes/mu and a film width of 155-165 cm, with a spacing between outlets from 9 to 10 cm, fit width is 170-180 cm, config accepted irrigation ration under 1 film, 2 tubes, 8 rows: 12.5 cm + 26 cm + 12.5 cm + 26 cm + 12.5 cm + 26 cm + 12.5 cm + 47 cm, two drip tapes evenly distributed between 8 lines of rice; crop care; fertilization, namely the application of manure when plowing fields in late autumn at a rate of 15-20 t / hm ² and diammonium phosphate once at a rate of 40-50 kg / hm ² after which deep plowing is performed, the application of soluble organic fertilizers at a rate of 120-150 kg / hm ² and mineral fertilizers with a norm of pure nitrogen 330-345 kg / hm ² , with a preference for a norm of 330 kg / hm ² , P ₂ O ₅ - 150-160 kg / hm ² , K ₂ O 70-90 kg / hm ² , water-soluble Si fertilizer 25-30 kg/hm , boron fertilizer and zinc fertilizer 7 and 8 kg/hm ² respectively; pest control and other stages.

The disadvantages of these methods are the insufficiently high efficiency of rice production, which is due to the discrepancy between the soil and climatic conditions and the technical and technological capabilities of rice cultivation in China and on the lands of the reclamation and water management complex of the Abinsk district of the Krasnodar Territory, and, consequently, the inefficiency of the application of the set of techniques claimed in the inventions and technological operations, as well as the proposed schemes for laying out the drip tape, planting rice, rice sowing rates, the timing and doses of mineral and organic fertilizers, as well as the timing of crop processing.

The closest technical solution to the claimed proposal is a method of sowing rice on drip irrigation under a plastic film, including growing rice under a plurality of plastic films for mulching by drip irrigation, including seed preparation; soil preparation, including preventing the spread of weeds, carried out by tilling the soil before sowing, spraying with mixed herbicides after sowing, and re-spraying with mixed herbicides after 45-15-25 days; sowing in rows; seedling management using rooting stimulants through a drip irrigation system from planting to the tillering phase; management of rice irrigation through a drip irrigation system with an irrigation rate of 10500-12000 m ³ /hm ² during the entire growing season of rice or carried out according to the stages of rice vegetation: from the seedling stage to the trefoil stage: in case of poor soil moisture after rice cultivation, irrigate 2-3 times , total watering volume 900-1200 m ³ /hm ² , from the trefoil stage to the initial period of the booting phase: watering 8-10 times, the total watering volume 2400-2700 m ³ /hm ² , from the initial period of the booting phase up to heading phase: watering 9-10 times, total watering 2700-3000 m ³ /hm ² , from heading to flowering phase: watering 5-6 times, total watering 1200-1500 m ³ /hm ² , from the flowering phase to the ripening stage: carrying out irrigation 14-16 times, with a total irrigation volume of 3300-3600 m ³ /hm ² or by drip irrigation 38-45 times during the entire growing season of rice; fertilization management When, from planting to rice seedling maturation, plants are fertilized with pure nitrogen fertilizer in the amount of 330-345 kg/hm, or when special requirements for the management of various fertilizers, use the following technology: base fertilizer: once evenly apply manure for deep plowing of fields in late autumn at a rate 15-20 t/hm ² and 40-50 kg/hm ² dimonium phosphate; fertilizer for seedlings: if the soil is saline, alkaline, has uneven fertility, has a lack of nutrients, spotting and some weak seedlings then apply 20-30 kg/hm pure nitrogen, 25-30 kg/hm ² P ₂ 0 ₅ , 10-15 kg / hm ² K ₂ 0 and 3.5-4 kg / hm ² zinc fertilizers are dripped together with water in 2-3 repetitions to stimulate the growth of seedlings; fertilizer for the tillering phase: 110-120 kg/hm ² pure nitrogen, 30-40 kg/hm ² P ₂ 0 ₅ , 10-15 kg/hm ² K ₂ 0, 25-30 kg/hm ² water-soluble Si fertilizer, 7-8 kg/hm ^{2 of} boron fertilizer and 3.5-4 kg/hm ^{2 of} zinc fertilizer are applied together with water 3 times; fertilizer for the initial phase of entering the tube: 110-120 kg / hm ^{2 of} pure nitrogen are applied 2-3 times, P ₂ 0 ₅ 35-40 kg / hm ² , K ₂ 0 25-30 kg / hm ² and 60-75 kg/hm ² soluble organic fertilizer; fertilizer for the heading phase: 3-4 times repeated: from 50 to 60 kg/hm ² pure nitrogen, P ₂ 0 ₅ 30-40 kg/hm ² , K ₂ 0 25-30 kg/hm ² and 60-75 kg /hm ² soluble organic fertilizer or application of a general fertilizer system for the growing season of rice consisting of and applying 15-20 kg/hm ² manure, 120-150 kg/hm ² soluble organic fertilizer, 300-330 kg/hm ² pure nitrogen, 150-160 kg/hm ² P ₂ 0 ₅ , 70-90 kg/hm ² K ₂ 0, 25-30 kg/hm ² water-soluble Si-fertilizer, 7-8 kg/hm ² boron fertilizer and zinc fertilizer, respectively; while the sowing density is 33300-36000. holes/mu, the width of each film is 215-225 cm, and the distance between the water outlets of the drip tape is 9 to 10 cm, placing every twelve rows of rice under one film, and using three drip tapes so that the distances between adjacent rows are as follows: 13 cm, 24 cm, 13 cm, 20 cm, 13 cm, 24 cm, 13 cm, 20 cm, 13 cm, 24 cm, 13 cm and 50 cm respectively, with three drip tapes evenly distributed between twelve rows of rice or at a density crops 30500-32600 holes/mu, the width of each film is 155-165 cm, the distance between the water outlets of the drip tape is 9 to 10 cm, placing eight rows of rice under one film and using two drip tapes so that the distances between adjacent rows are as follows: 12.5 cm, 26 cm, 12.5 cm, 26 cm, 12.5 cm, 26 cm, 12.5 cm and 47 cm, respectively, with two drip tapes evenly distributed between eight rows of rice. (Method of drip irrigation under plastic film for rice cropping) (U.S. Pat. No. 10278341, B2, 05/07/2019).

The disadvantages of this method are the inefficiency and / or impossibility of implementing the set of methods and technological operations proposed in the method, as well as their implementation in the stated sequence in the conditions of the reclamation and water management complex of the Abinsky district of the Krasnodar Territory, which is due to soil and climatic conditions, varietal and technological capabilities. In particular, the rice-growing regions of the PRC are located in a subtropical and tropical climate with the sum of active temperatures and solar activity during the growing season significantly exceeding the average values of these values for the rice-growing regions of the Abinsk region of the Krasnodar Territory. The physical and chemical properties of secondary-calcareous rice soils prevailing in the rice-growing regions of China differ from the meadow-chernozem, meadow, alluvial meadow-bog (heavy merged chernozems) soils of the reclamation and water management complex of the Abinsk district of the Krasnodar Territory, most of which since the beginning of use for rice cultivation lose favorable physical properties and become degraded, merged, viscous, gleyed formations. The use of root stimulants is not effective in the cultivation of seedling rice due to the cultivation of rice seedlings on protected ground. Irrigation of rice through a drip irrigation system with an irrigation rate of 10500-12000 m ³ /hm ² during the entire growing season of rice or carried out according to the stages of rice vegetation with specified irrigation rates, timing and number of irrigation cannot be implemented in the natural and climatic conditions and soils of the Abinsk region Krasnodar Territory.

The technical result of the invention is to increase the productivity and quality of biometric indicators of rice crops, improve the ameliorative state of soils, reduce irrigation rates, reduce labor intensity and cost of rice production.

The technical result is achieved by the fact that in the known method of rice cultivation, including the cultivation of rice on drip irrigation under a plastic film, the preparation of seeds, soil and seedlings, the management of rice irrigation through a drip irrigation system and the application of fertilizers, according to the invention, rice is cultivated on lands of an irrigated rice fund under underground drip irrigation under plastic and/or biodegradable perforated film, beforehand in the first year of rice cultivation in autumn, after harvesting the predecessor, the main tillage is carried out once to a depth of 0.18-0.22 m, loosening with chisels to a depth of 14-16 cm, then disking is carried out with the incorporation of organic fertilizers to a depth of 0.10-0.12 m with an application rate of 40-50 tons per 1 ha of manure or green manure, after which in the spring of the first year of the implementation of the method, the main highway and underground hoses and / or drip irrigation tapes are laid to a depth not higher than the middle of the root system of rice crops ota and depth of tillage, while the step between the water outlets of the underground hose and / or drip irrigation tape is 20 cm, with the diameter and wall thickness of the drip hose and / or tape - 16 mm and 0.9 mm, respectively, and the water outlet of the drip hose and / or tape in l / h per 1 m is taken from the condition of providing the required moisture in a given soil layer for crops of rice crop rotation, while the distance between drip hoses and / or tapes is 56 cm, then the annual spring-autumn technological cycle of work is performed, including: harrowing with tine harrows in two tracks to a depth of 0.08 m, then the soil surface is leveled and rolled; preparation of rice seeds, including their treatment against seed infection and a single pre-sowing treatment with a growth regulator, and pre-planting irrigation before planting rice seedlings is carried out with a soil moisture rate of 90% of the lowest moisture capacity in a layer of 0.6 m and the soil surface is treated with soil herbicides, then for the soil surface is laid with a perforated mulching film between the strips of which technological driveways and passages are made, which are covered with non-woven geosynthetic material, while the width of the strips of the perforated mulching film and the distance between its strips depends on the technical characteristics of the equipment used for the cultivation of rice and associated crops of the rice crop rotation; at the same time, the condition of moistening the soil in the root layer is observed with one underground drip hose and / or a tape of two rows of perforations on the mulch film in which rice seedlings are planted, and the perforation diameter is equal to the diameter of a peat pot with a nutrient substrate in which from 1 to 4 rice plants are grown and located at a distance of 10 cm from the axis of laying the underground hose and / or drip irrigation tape and 20 cm in a row and between adjacent perforations; then, rice seedlings are planted in the perforation of the mulching film in the phase of 6-7 leaves with a green color, a well-developed root system and not infected with pests and diseases, which is sprayed with biologically active substances 1-2 days before planting in open ground, then after planting the seedlings rice is irrigated through an underground drip irrigation system throughout the growing season with a frequency and irrigation rate depending on compliance with the condition for ensuring a constant soil moisture of 80% of the lowest moisture capacity in a layer of 0.4 m, then mineral fertilizers are applied in an amount of 25% of the full norm of mineral fertilizers with two equal rates of N ₂₀ P ₁₀ K ₅ in kg AI / ha in the phase of 8-9 leaves after full establishment and in the tillering phase by fertigation through an underground drip irrigation system, then the rice plants are treated with pesticides in the tillering phase, biologically active substances at the end of the tillering phase before the start of the tube; twice with fungicides in the phase of entry into the tube and again after 20-25 days, with insecticides during the growing season when pests exceed the economic threshold of harmfulness; after ripening, rice is harvested; pre-planting irrigation before planting the accompanying crops of the rice rotation through an underground drip irrigation system with the simultaneous application of mineral fertilizers, planting seedlings and/or sowing of the accompanying crops of the rice rotation followed by their treatment with pesticides, fungicides and insecticides, and the rice crops are irrigated through the underground drip irrigation system during the growing season; then, after the maturation of the accompanying crops of the rice crop rotation, they are harvested, after which a perforated mulch film is collected from the soil surface, and in the case of using a biodegradable mulch film, it is left on the soil surface, then deep loosening is carried out to a depth of 0.14-0.16 m , disking with incorporation of organic fertilizers to a depth of 0.10-0.12 m with an application rate of 40-50 tons per 1 ha of manure or green manure, after which the annual spring-autumn technological cycle of work is repeated.

The novelty of the claimed invention is due to the pioneering technology in the Russian Federation for the cultivation of rice on agricultural land not related to rice irrigation systems with underground drip irrigation under plastic and / or biodegradable perforated film, the introduction of which improves the quality of the resulting grain by creating optimal conditions for the vegetation of rice crops; improve the ameliorative state of soils, the granulometric composition of the soil, as well as the biometric indicators of the rice crop as a result of the transition to flood-free rice cultivation technology; reduce irrigation norms, labor intensity and cost of rice production by reducing the number of necessary technological operations, reducing the doses of applied macro and microelements, reducing suffusion and nutrient removal from the soil; increase profitability by reducing the irrigation rate and reduce the application of organic and mineral fertilizers.

The use of agricultural land not related to rice irrigation systems for the cultivation of rice on underground drip irrigation under plastic and / or biodegradable perforated film allows agricultural producers to produce rice without being “attached” to rice systems, which allows increasing production volumes, reducing the cost of the resulting products of rice crop rotation crops , to use fundamentally new rice crop rotations with the inclusion of gourds and vegetables in them, to increase the profitability and product quality of rice crop rotations, to reduce the need for irrigation water, to improve the ecological situation in the rice irrigation system.

The use of underground drip irrigation allows: to increase the profitability of rice production by saving irrigation water; reduce the cost of rice production by reducing technological operations due to the absence of the need to carry out annual maintenance and operational activities on the rice system and the doses of macro and microelements introduced as a result of the absence of suffusion; eliminate the removal of nutrients from the soil in comparison with the traditional technology of flooding rice fields; perform tillage at any convenient and / or necessary time, while the soil is moistened only in the root zone, which does not interfere with the implementation of the required agricultural practices, including harvesting; improve the reclamation state of the soil due to the use of non-flood cultivation technology, increase productivity.

The main tillage is carried out to control weeds, activate redox processes in the soil, protect the soil from erosion processes, improve the soil structure, while the optimal plowing depth for the soil conditions of the Abinsk district of the Krasnodar Territory is 0.18-0.22 m, which is sufficient to destroy the plow pan and provide the best water filtration from the arable horizon.

Autumn loosening with chisels, which in the soil conditions of the Abinsky district of the Krasnodar Territory, is performed after the main tillage to a depth of at least 0.14-0.16 m is carried out for: weed control by destroying young entries and roots of weeds located on the soil surface after plowing the soil, preventing the soil from drying out, creating favorable conditions for the unhindered removal of excess moisture to the lower layers of the soil, and activating the respiratory activity of the soil.

Autumn disking of the soil, in the soil conditions of the Abinsk district, the Krasnodar Territory, is carried out in late autumn to a depth of 0.10-0.12 m and combined with the incorporation of organic fertilizers to control young shoots of weeds, create favorable reclamation conditions in spring, increase the agro-resource potential of the soil and accumulate nutrient reserves for crops of rice crop rotation, their good survival and survival.

The application of organic fertilizers provides additional soil nutrition and naturally transforms the soil structure, allows you to obtain environmentally friendly crops of rice and related crops of rice crop rotation, stimulates the vital activity of beneficial microorganisms, while the application rate of 40-50 tons per 1 ha of manure or green fertilizer is necessary and sufficient to replenish natural fertility in the soils of the Abinsk region of the Krasnodar Territory.

Spring harrowing with tooth harrows, which, under the soil conditions of the Abinsk district of the Krasnodar Territory, is carried out in early spring to a depth of 0.08 m for crumbling, loosening, mixing and leveling the soil surface, damaging and destroying seedlings and weed shoots, destroying the surface soil crust and activating the respiratory soil activity.

The leveling of the field surface is carried out in order to exclude local depressions on the field surface and to prevent the formation of "saucers" on the mulch film after its laying, which provoke the growth of weeds, the accumulation of precipitation and the processes of destruction of the mulch film; creation of favorable conditions for simultaneous seedlings of rice crops and the formation of a uniform moistening contour from immiters; minimize the likelihood of the development of processes of fusion and degradation of the soil, the destruction of weed shoots, the breaking of lumps and the soil surface under the laying of the mulching film.

The rolling of the soil surface is performed to: increase the throughput and contact of seeds with the soil, which, after sowing rice, increases the access of moisture to the seeds and, as a result, seedlings appear faster; creating favorable conditions for better, uniform sowing; prevention of subsidence of the earth and failure of seeds after crops; creating favorable conditions for successful germination and increasing seed germination; reducing evaporation and drying of the soil; increasing the quality of soil cultivation, in cases where the land was poorly plowed or with high humidity, after which many lumps and lumps remained on its surface.

Covering technological driveways and passages with non-woven geosynthetic material is necessary to prevent the germination of weeds in them and to create the possibility for agricultural machinery to move along them in any weather without overcompacting the soil and forming ruts.

The use of underground drip irrigation makes it possible to ensure the distribution of the required moisture in the root layer with the best efficiency due to the fact that the underground hose and / or drip irrigation tape is at the level of the center of the root system of rice crop rotation plants. The use of underground hoses and / or drip irrigation tapes with a step between water outlets of 20 cm makes it possible to form moistening zones on the soils of the Abinsk district of the Krasnodar Territory with the best efficiency, and the diameter of drip tapes equal to 16 mm and located at a distance of 56 cm from each other most effectively provides during the growing season of rice, soil moisture is 80% of the lowest moisture capacity in a layer of 0.4 m, which is a necessary and sufficient condition for normal rice vegetation, as well as the creation of the required pre-sowing moisture in a given soil layer. Wall thickness of underground hoses and / or drip irrigation tapes should be at least 0.9 mm, which is due to the need for its effective operation over an 8-year period in the soils of the Abinsk district of the Krasnodar Territory, including when using them for fertigation.

Laying underground hoses and/or drip irrigation tapes to a depth not higher than the middle of the root system of rice crop rotation and not higher than the depth of tillage is a mandatory and sufficient condition for the formation of an optimal zone of moistening of the root layer of the soil and ensuring a given soil moisture, and also allows minimizing the irrigation rate and doses of applied fertilizers, to achieve maximum efficiency in the availability of water and fertilizers to plants in the rice crop rotation.

The scheme of laying the drip hose and/or tape is carried out in compliance with the condition of underground irrigation with one drip hose and/or tape of two rows of perforations on the mulch film, which achieves the maximum efficiency of distribution of moisture zones in the root zone and helps to minimize the consumption of irrigation water required to maintain optimal humidity. only for rice crops, but also concomitant for crops of rice crop rotation.

Treating the soil surface with soil herbicides before covering the soil with a perforated mulching film allows you to create a so-called soil screen on it, upon reaching which weed shoots die, and crops continue to grow, it also allows you to maintain the integrity of the film from gusts of weeds.

The use of plastic and/or biodegradable perforated film makes it possible to: reduce the irrigation rate by reducing evaporation losses from the soil surface; to level the daily amplitude of the temperature of the arable horizon of the soil, as well as to accelerate the time of soil warming, and, consequently, the time of planting rice seedlings, which will also increase the growing season for the accompanying crops of the rice crop rotation; improve the development of the root system of cultivated mulched crops due to the formation of a large number of adventitious roots; to prevent the ingress of pathogens from the soil onto the plant during irrigation and / or precipitation; to reduce the infestation of crops with weeds and to reduce the dose of herbicides due to this; exclude the appearance of a soil crust, which ensures the normal growth and development of the plant; activate the development of worms and microorganisms; to preserve the best presentation of the fruits of the accompanying crops of the rice crop rotation due to the lack of their contact with the ground.

The use of perforated mulch film makes it possible to simplify the process of planting seedlings of rice and crops of rice crop rotation, that is, to reduce the number of technological agricultural practices, and also provide the necessary conditions for the germination of crops of rice crop rotation.

The use of a biodegradable mulching film makes it possible to cultivate winter crops of vegetables: carrots, beets, onions, garlic, parsnips, parsley, sorrel, spinach, dill, and the biodegradable film crushed and plowed into the arable layer, as a result of its decomposition by bacterial colonies, will increase the number of microorganisms and worms, thereby will thereby improve the soil structure and the reclamation state of the arable horizon of the soil.

The use of rice seedlings allows you to speed up the time of harvesting rice, and thereby increase the growing season for the accompanying crops of rice crop rotation, while the soil and climatic conditions for growing seedlings should correspond as much as possible to the conditions of the Abinsk district of the Krasnodar Territory, in connection with this, it is recommended to grow seedlings in nutrient pots, in substrate, the components of which: highly fertile field land, soddy land, humus, high-moor peat, coarse sand should be taken in such a ratio that the humus content in the substrate is not lower than 60%, the density of the substrate is 0.8-1.0 g / cm ³ , porosity - 80-90%, air content - not less than 15-20% with the addition of microelements to the substrate before planting rice seeds in the amount of 75% of the full norm N ₁₆₀ P ₈₀ K ₄₀ in kg AI / ha and one top dressing nitrogen fertilizers in the phase of 2-3 sheets with a norm of N ₄₀ in kg of AI / ha, maintaining the temperature during the period of growing seedlings: during the day 24-26 ° C, in cloudy weather - 20- 22 °С, at night - 18-20 °С, optimal pre-irrigation humidity of the substrate at the level of 80% of the lowest moisture capacity, relative air humidity - 70-80% and illumination: the first three days, the time of illumination is 24 hours, after the third day - at least 12 -14 hours depending on daylight hours and weather conditions.

Growing rice seedlings in an amount of 1 to 4 plants in one nutrient pot with a diameter of 8 cm allows planting rice in the perforation of a mulch film without injuring rice plants, minimizing plant stress during transplantation, and increasing the survival and productivity of rice.

Planting up to 4 rice plants in one perforation of the mulching film will provide an increase in the resulting yield by an average of 3.5 times per 1 m without negative changes in the biometric characteristics of rice plants.

Pre-sowing irrigation should be carried out before sowing crops of rice crop rotation in order to create the necessary moisture reserve in the soil, the norm providing soil moisture of 90% of the lowest moisture capacity in a layer of 0.6 m to obtain friendly seedlings and better development of plants at the beginning of the growing season, as well as reducing the time adaptation of rice seedlings planted in open areas.

The use of fertigation makes it possible to most effectively apply pesticides and / or plant nutrition through underground drip irrigation, simultaneously with irrigation (irrigation), which minimizes the irrational use of drugs, reduces fertilizer doses and the cost of production of rice crop rotation.

Two top dressings to increase the amount of mobile nutrients nitrogen, potassium and phosphorus in the root zone of rice, which are consumed by the plant as it grows, must be performed at a dose of 25% of the full rate of mineral fertilizers, which, on average, for the conditions of the Abinsky district of the Krasnodar Territory is N ₁₆₀ P ₈₀ K ₄₀ in kg AI / ha and is adjusted depending on the agricultural background and the adopted crop rotation and is applied in two equal rates of N ₂₀ P ₁₀ K ₅ in kg AI / ha in the phase of 8-9 leaves after full establishment and in the phase tillering by fertigation through an underground drip irrigation system.

Care of rice plants during the growing season is carried out in accordance with their biological and climatic characteristics, namely, the treatment with pesticides must be carried out in the tillering phase, biologically active substances at the end of the tillering phase before the start of the tube; twice with fungicides in the phase of entry into the tube and again after 20-25 days, as well as in case of exceeding the economic threshold of harmfulness by pests, insecticide treatment is performed.

The use of new rice crop rotations with the inclusion of gourds and vegetables in them makes it possible to optimize the use of lands, taking into account their possible effective fertility, the biological potential of plants and the available resources (heat, climate, fertilizers, agricultural machinery and agrochemicals) in order to conduct the most profitable management possible. when obtaining high yields, with simultaneous reproduction of fertility and environmental protection.

The essence of the invention is illustrated by drawings, where in Fig. 1 shows a technological scheme of one grip when cultivating rice and related crops of rice crop rotation on underground drip irrigation with laying an underground drip hose and / or tape to a depth of 0.18 m under a mulching film, including biodegradable one: in Fig. 2 shows a fragment of the left part of the technological scheme of one grip when cultivating rice and related crops of rice crop rotation on drip irrigation with laying an underground drip hose and / or tape to a depth of 0.18 m under a mulch film, including biodegradable one: in fig. 3 too, section A-A; in fig. 4 shows a fragment of the central part of the technological scheme of one grip when cultivating rice and related crops of rice crop rotation on drip irrigation with laying an underground drip hose and / or tape to a depth of 0.18 m under a mulch film, including biodegradable one: in Fig. 5 too, section B-B.

In the drawings, the dimensions of the elements of the technological scheme of one grip are indicated in centimeters.

Technological scheme of one capture when cultivating rice contains: 1 - underground drip hose and/or tape; 2 - technological passage; 3 - round perforation in the mulching film for planting crops; 4 - mulching film; 5 - technological passage; 6 - outlets (Fig. 6).

The rice cultivation method is carried out as follows

In the autumn in the first year of the implementation of the method of rice cultivation on agricultural lands not related to rice irrigation systems on underground drip irrigation under plastic and / or biodegradable perforated film 4, previously in the first year of rice cultivation, the following is performed once:

- basic tillage to a depth of 0.18-0.22 m,

- loosening with chisels to a depth of 14-16 cm,

- disking with incorporation of organic fertilizers to a depth of 0.10-0.12 m with an application rate of 40-50 tons per 1 ha of manure or green manure.

In the spring of the first year of the implementation of the method, the main highway and underground hoses and/or drip irrigation tapes 1 are laid to a depth not higher than the middle of the root system of rice crop rotation and the depth of tillage, while the step between the outlets 6 of the underground hose and/or drip irrigation tape 1 is equal to 20 cm, with a diameter and wall thickness of the drip hose and/or tape 1 equal to 16 mm and 0.9 mm, respectively, and the water outflow of the drip hose and/or tape 1 in l/h per 1 m is taken from the condition of providing the required humidity in a given soil layer for crops of rice crop rotation, while the distance between drip hoses and / or tapes 1 is 56 cm.

Next, the annual spring-autumn technological cycle of work is performed, including:

- harrowing with tooth harrows in two tracks to a depth of 0.08 m;

- leveling the soil surface;

- rolling of the soil surface;

- preparation of rice seeds, including their dressing against seed infection and a single pre-sowing treatment with a growth regulator;

- pre-planting watering before planting rice seedlings with a norm providing soil moisture of 90% of the lowest moisture capacity in a layer of 0.6 m;

- treatment of the soil surface with soil herbicides;

- laying a perforated mulching film 4 on the soil surface, between the strips of which technological passages 5 and passages 2 are made, which are covered with non-woven geosynthetic material, while the width of the strips of the perforated mulching film 4 and the distance between its strips depends on the technical characteristics of the equipment used for the cultivation of rice and accompanying crops of rice crop rotation, while observing the condition of moistening the soil in the root layer with one underground drip hose and / or tape 1 of two rows of perforations 3 on the mulch film 4, in which rice seedlings are planted, and the diameter of the perforation 3 is equal to the diameter of the peat pot with a nutrient substrate, in which from 1 to 4 rice plants are grown and located at a distance of 10 cm from the axis of laying the underground hose and/or drip irrigation tape 1 and 20 cm in a row and between adjacent perforations;

- treatment of rice seedlings with biologically active substances 1-2 days before planting in open ground;

- planting rice seedlings in perforation 3 of mulching film 4 in the phase of 6-7 leaves with green color, well-developed root system and not infected with pests and diseases;

- watering rice seedlings after planting them in perforation 3 through an underground drip irrigation system throughout the growing season with a frequency and irrigation rate depending on compliance with the condition for ensuring constant soil moisture of 80% of the lowest moisture capacity in a layer of 0.4 m;

- application of mineral fertilizers in the amount of 25% of the total rate of mineral fertilizers with two equal rates of N ₂₀ P ₁₀ K ₅ in kg AI / ha in the phase of 8-9 leaves after full establishment and in the tillering phase by fertigation through an underground drip irrigation system ;

- treatment of rice plants with pesticides in the tillering phase;

- treatment of rice plants with biologically active substances at the end of the tillering phase before the start of the tube;

- treatment of rice plants twice with fungicides in the phase of entry into the tube and again after 20-25 days;

- treatment of rice plants with insecticides during the growing season when pests exceed the economic threshold of harmfulness;

- rice harvesting;

- pre-planting irrigation before planting the accompanying crops of rice crop rotation through an underground drip irrigation system with the simultaneous application of mineral fertilizers;

- planting seedlings and/or sowing of accompanying crops of the rice rotation followed by their treatment with pesticides, fungicides and insecticides;

- watering crops of rice crop rotation through an underground drip irrigation system during the growing season;

- harvesting of accompanying crops of rice crop rotation after their maturation;

- cleaning perforated mulching film 4 and drip tape 1, and in the case of using a biodegradable mulching film, it is left on the soil surface;

- deep loosening to a depth of 0.14-0.16 m;

- disking with incorporation of organic fertilizers to a depth of 0.10-0.12 m with an application rate of 40-50 tons per 1 ha of manure or green manure.

Then the annual spring-autumn technological cycle of work is repeated. Example of implementation of the rice cultivation method

Testing of the method of cultivating rice of the Rapan variety was carried out in the Krasnodar Territory at LLC KH "Pugach S.G." Abinsky district of the Krasnodar Territory on an experimental field with an area of 5 hectares.

The cultivated rice crop was Rapan variety.

The predecessor in the first year of the implementation of the method - fig.

On the experimental field from 2016 to 2019, the following crop rotation was applied:

- 2016: rice (seedlings) + melons (seedlings);

- 2017: rice (seedlings) + chickpeas (seed);

- 2018: rice (seedlings) + tomatoes (seedlings);

- 2019: rice (seedlings) + vetch (seed).

The method of cultivating rice on agricultural land not related to rice irrigation systems with underground drip irrigation under polyethylene and biodegradable perforated mulching film included a list of technological operations presented in Table 1.

As a result of approbation of the method of rice cultivation on agricultural lands that are not related to rice irrigation systems, on drip irrigation under polyethylene and / or biodegradable perforated mulching film, it was possible to prove the effectiveness of not only rice cultivation (Table 2), but also rice crop rotation crops (Table 3) .

The use of the claimed method of rice cultivation has improved the ameliorative state of soils (table 4).

As a result of rice cultivation on underground drip irrigation under polyethylene and mulching perforated film on agricultural lands that do not belong to rice irrigation systems, the effectiveness of the rice cultivation technology developed by us has been proven. The developed technology is a more environmentally friendly farming system for rice cultivation than traditionally used in the rice-growing sector of Russia.

The proposed technology allows rice-growing state farms to produce elite rice seeds, which allows not only to significantly save on the purchase of seed, but also to increase the profitability of rice production.

The proposed technology reduces the anthropogenic load and improves the environmental and reclamation situation in the rice irrigation system. Due to the lack of groundwater contact with irrigation water, not only the process of removal of mineral, organic and chemical plant treatment products to the underlying layers was stopped, but also their further movement to the water intake (rivers, lakes, estuaries), which has a beneficial effect on the environment and health person.

The main indicators of the effectiveness of the proposed method are:

- increase in rice productivity by an average of 2.5 times;

- an annual average decrease in the irrigation rate by 5.6 times relative to the traditional technology of rice cultivation by flooding;

- improvement of the ameliorative state of soils from “satisfactory” to “good” in 2019;

- reduction of labor intensity by 47%;

- reduction in the cost of rice production by an average of 32%;

- reduction of doses of macro and microelements introduced by an average of 38%.

Claims (1)

A method of rice cultivation, including growing rice on drip irrigation under a plastic film, preparing seeds, soil and seedlings, managing rice irrigation through a drip irrigation system and applying fertilizers, characterized in that rice is cultivated on lands of an irrigated rice fund with underground drip irrigation under plastic and /or biodegradable perforated film, previously in the first year of rice cultivation in the fall, after harvesting the predecessor, the main tillage is carried out once to a depth of 0.18-0.22 m, loosening with chisels to a depth of 14-16 cm, then disking is carried out with the incorporation of organic fertilizers to a depth of 0.10-0.12 m with an application rate of 40-50 tons per 1 ha of manure or green manure, after which in the spring of the first year of the implementation of the method, the main highway and underground hoses and / or drip irrigation tapes are laid to a depth not higher than the middle of the root rice crop rotation system and tillage depth, while the step between the waters outlets of the underground hose and/or drip irrigation tape is 20 cm, with a diameter and wall thickness of the drip hose and/or tape of 16 mm and 0.9 mm, respectively, and the water outflow of the drip hose and/or tape in l/h per 1 m is taken from conditions for ensuring the required moisture in a given soil layer for crops of rice crop rotation, while the distance between drip hoses and / or tapes is 56 cm, then the annual spring-autumn technological cycle of work is performed, including: harrowing with toothed harrows in two tracks to a depth of 0.08 m, then leveling and rolling the soil surface; preparation of rice seeds, including their treatment against seed infection and a single pre-sowing treatment with a growth regulator, and pre-planting irrigation before planting rice seedlings is carried out with a rate that provides soil moisture of 90% of the lowest moisture capacity in a layer of 0.6 m, and the soil surface is treated with soil herbicides, further, a perforated mulching film is laid on the soil surface, between the strips of which technological passages and passages are made, which are covered with non-woven geosynthetic material, while the width of the strips of the perforated mulching film and the distance between its strips depends on the technical characteristics of the equipment used for the cultivation of rice and related crops of rice crop rotation; at the same time, the condition of moistening the soil in the root layer is observed with one underground drip hose and / or a tape of two rows of perforations on the mulch film in which rice seedlings are planted, and the perforation diameter is equal to the diameter of a peat pot with a nutrient substrate in which from 1 to 4 rice plants are grown located at a distance of 10 cm from the axis of laying the underground hose and / or drip irrigation tape and 20 cm in a row and between adjacent perforations; then, rice seedlings are planted in the perforation of the mulching film in the phase of 6-7 leaves with a green color, a well-developed root system and not infected with pests and diseases, which is sprayed with biologically active substances 1-2 days before planting in open ground, then after planting the seedlings rice is irrigated through an underground drip irrigation system throughout the growing season with a frequency and rate of irrigation, depending on compliance with the condition for ensuring a constant soil moisture of 80% of the lowest moisture capacity in a layer of 0.4 m, then mineral fertilizers are applied in an amount of 25% of the full rate mineral fertilizers with two equal rates of N ₂₀ P ₁₀ K ₅ in kg AI / ha in the phase of 8-9 leaves after full establishment and in the tillering phase by fertigation through an underground drip irrigation system, then the rice plants are treated with pesticides in the tillering phase, biologically active substances at the end of the tillering phase before the start of the tube; twice with fungicides in the phase of entry into the tube and again after 20-25 days, with insecticides during the growing season when pests exceed the economic threshold of harmfulness; after ripening, rice is harvested; pre-planting irrigation before planting the accompanying crops of the rice rotation through an underground drip irrigation system with the simultaneous application of mineral fertilizers, planting seedlings and/or sowing of the accompanying crops of the rice rotation followed by their treatment with pesticides, fungicides and insecticides, and the rice crops are irrigated through the underground drip irrigation system during the growing season; then, after the maturation of the accompanying crops of the rice crop rotation, they are harvested, after which a perforated mulch film is collected from the soil surface, and in the case of using a biodegradable mulch film, it is left on the soil surface, then deep loosening is carried out to a depth of 0.14-0.16 m, disking with incorporation of organic fertilizers to a depth of 0.10-0.12 m with an application rate of 40-50 tons per 1 ha of manure or green manure, after which the annual spring-autumn technological cycle of work is repeated.

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