Winter Wheat

Economic importance

Winter wheat is the most valuable and productive grain crop. Its grain contains a large amount of gluten proteins and other valuable substances, so it is widely used for food purposes: in bread baking, the confectionery industry, for the production of groats and pasta products.

Wheat bran is a concentrated feed for all types of farm animals and poultry. In 100 kg of bran there are 70-80 feed units and 11 kg of digestible protein. Straw and chaff also have feed value. Straw in chopped, steamed, or chemically treated form is used to feed cattle and sheep. In 100 kg of straw there is 0.5-1.0 kg of digestible protein and 20-22 feed units. Straw can be used as a building material, for paper making, and as bedding for animals. In some regions of Ukraine and the Central Chernozem zone, winter wheat is used for green fodder.

Cultivation regions and yield

In Russia before the Revolution, winter wheat was grown almost only in the south. At present, winter wheat is used from the south of Arkhangelsk Oblast to the southern regions of Turkmenistan.

The main crops of winter wheat are concentrated in regions with favorable overwintering conditions.

In the USSR, the areas occupied by winter wheat crops were about 6 million ha in Ukraine and were located in the forest-steppe, northern, central, and southern steppe oblasts; about 5 million ha in the North Caucasus; and about 3 million ha in the Central and Central Chernozem regions. Fertile chernozem soils with sufficient precipitation during the growing season and relatively warm winters created favorable conditions for obtaining high and stable yields in these regions.

Good conditions also develop in southern Kazakhstan, the countries of Central Asia, Transcaucasia, and the Central Chernozem zone. Fairly large areas of winter wheat crops are concentrated in the Volga region.

In the central regions of the Non-Chernozem zone, the areas of winter wheat increased by the early 1990s by more than 20 times compared with 1913. Large areas are occupied in Moscow, Bryansk, Kaluga, Vladimir, and Tula oblasts.

In the 1990s in Russia, winter wheat crops occupied over 9 million ha with an average yield of 2.0 t/ha. Modern varieties with a high level of agronomic practice make it possible to obtain yields of 4-5 t/ha, including in the Non-Chernozem zone.

In 2001-2005 in Russia, the sown area of winter wheat was 9 million ha, or 37% of the total wheat area and 20% of the total area of grain crops. The gross harvest was 23 million t, or 52% of the total wheat harvest and 29% of the total grain harvest. The average yield was 2.68 t/ha, for spring wheat 1.5 t/ha, and for all grain crops 1.89 t/ha.

Among grain crops, winter wheat with proper agronomic practice gives high yields in many regions of its cultivation, primarily in the North Caucasus and Ukraine. On farms of Rostov Oblast, grain yield was 3.5-4.0 t/ha; in Krasnodar Krai, on average more than 5 t/ha. In Moscow Oblast, on the fields of the crop production laboratory of MAA, over many years on occupied fallow it was possible to obtain on average 5.0-5.3 t/ha.

According to the experiments of the network of variety testing plots, winter wheat has large reserves and opportunities for increasing yields. According to long-term data, the yield at variety plots was 0.6-0.8 t/ha higher than on the general massifs of the same farm, although not all variety plots used a complex of high agronomic practices.

Biological characteristics

Soil requirements

Winter wheat is characterized by high demands on soil. The reaction should be neutral pH 6-7.6. It gives the highest and most stable yields on fertile, well-moistened chernozem and dark chestnut soils free of weeds. In the Non-Chernozem zone, slightly podzolized, medium loamy, and gray forest soils are better suited. It does poorly on light sandy, clayey, wet soils, and drained peat bogs. On poor sandy and podzolic soils on unfertilized fields and in drought, tillering is greatly inhibited.

The relief has a great influence on yield. Low-lying swampy places are unfavorable for winter wheat.

The root system of winter wheat does not efficiently absorb hard-to-access substances from the soil, so a deficiency of phosphorus and potassium nutrition affects hardening and overwintering. Spring regrowth in this case occurs more slowly than in rye, and the need for nitrogen top dressing increases.

Vegetation

The growing season is 240-350 days. With good soil moisture, new roots form from the tillering nodes in spring; this process can continue until the end of milk ripeness of the grain.

On chernozems by the end of the growing season, the root system can reach a depth of up to 2.5 m; on less fertile soils, much less. On irrigated lands, most of the root system forms in the moistened layer.

Stem elongation in central Russia occurs in the first half of May at a temperature of at least +10 °C; heading occurs after 30-35 days. The intensity of heading increases as the photoperiod and temperature increase.

From spring awakening to heading in various climatic conditions of the country, 70-80 days pass. In the north it is faster, since the spring day length is longer.

Organic and nitrogen fertilizers lengthen the period to heading; phosphorus-potassium fertilizers shorten it by 2-4 days.

At temperatures from +12 to +30 °C, flowering lasts 7 days; in hot and dry weather, 3-5 days. Strong wind, dry air, and drought promote the appearance of empty grains.

Grain formation and filling continue for about 30 days depending on the variety and soil-climatic conditions. Optimal conditions for ripening develop at air humidity of 50% and a temperature of 16-21 °C. Droughty weather shortens the ripening period; rainy and cool weather lengthens it.

The period from full ripeness to physiological ripening of grain is from 20 to 40 days.

Crop rotation

Winter wheat is demanding as to its predecessors. First of all, fields are timely freed from fallow-occupying crops for soil preparation and sowing, weed control is carried out, and measures aimed at preserving and accumulating moisture are taken. Timely implementation of these measures makes it possible to obtain uniform seedlings and good development of winter crops in autumn, which contributes to better overwintering and a high yield.

The predecessors of winter wheat in crop rotation depend on the soil-climatic conditions of cultivation.

In the zone of insufficient and unstable moisture, the best predecessor is black fallow, which allows moisture accumulation and increases the content of nitrates and other nutrients in the soil. Black fallows contribute to higher wheat yields and high-quality grain.

At the Zernograd State Breeding Station of Rostov Oblast, the yield of winter wheat of the Bezostaya 1 variety averaged over 10 years was 51.2 c/ha after clean fallow and 25.9 c/ha after non-fallow predecessors. In dry years, the difference between clean fallow and a non-fallow predecessor increases. On average over 5 dry years, grain yield after fallow was 47.6 c/ha, and after non-fallow predecessors 13.7 c/ha. The protein content in grain was 16% and 14.4%, respectively; crude gluten 34.6% and 32.8%.

The main reason for the decrease in yield after non-fallow predecessors is low reserves of soil moisture. In addition, a dry autumn often leads to delayed sowing. Insufficiently developed autumn seedlings harden poorly and die in winter.

In the arid regions of the Southeast and the steppe regions of the South, coulisse fallows are important. Tall-stemmed crops are sown in fallow in summer, since they dry out the soil less than coulisses of spring sowing. According to data over 4 years of the Kharkov Agricultural Institute, sunflower is better suited for summer coulisses. On the experimental field, winter wheat after summer coulisses increased yield by 5-6 c/ha.

The dry steppe of the North Caucasus is characterized by a dry autumn, mild winter with little snow and recurring thaws, and hot summers with strong dry winds. An ice crust often appears on winter crops; in early spring, dust storms pose a threat to crops. At state variety plots in the dry steppe, the winter wheat yield after fallow is 2-3 times higher than after maize.

Under irrigation conditions, yields of up to 6-8 t/ha are possible without black fallow; in this case, row crops and grain legumes can be predecessors.

In the central, southeastern, and southern regions of the steppe zone of Ukraine, in southern Moldova, the steppe zone of the North Caucasus, in the middle and southeastern parts of the Central Chernozem zone, and in the Volga region, to obtain a stable winter wheat yield, crops should be placed predominantly after clean and black fallow.

Among other predecessors in these regions, maize for silage, grain legumes, and annual grasses are used (except sorghum and Sudan grass), as well as winter crops following black fallow.

Cereal crops, including winter wheat, should not be sown on the same field for more than 2 years in a row, since the number of disease and pest agents, for example, ground beetles, increases sharply.

According to data of the Krasnodar RIA, when sown two years in a row on the same field, the gluten content in grain decreases and its vitreousness decreases. However, fertilization improves grain quality.

In the zone of sufficient moisture, occupied fallows are important, which allow obtaining additional products with sufficiently good field preparation for sowing and applying fertilizers. Data from scientific institutions and leading farms confirm the economic efficiency of occupied fallows in this zone, but subject to the implementation of the entire agronomic complex.

Occupied fallows are introduced taking into account the real capabilities of farms without detriment to the yield of grain and subsequent crops.

In Polesie of Ukraine, Belarus, the Baltic countries, and the northwestern and central regions of the Non-Chernozem zone, winter wheat can be placed after perennial grasses, vetch-oat mixture, lupine for green fodder and silage, early potato, and pea. These predecessors allow timely soil preparation for sowing and good seedlings.

After grain legumes, the yield of winter crops is, as a rule, lower than after fallows. Yield decreases significantly after winter crops for grain, barley, maize for silage, sunflower, and other row crops.

In the forest-steppe regions of Ukraine, Moldova, the North Caucasus, and the Central Chernozem zone, winter wheat gives good yields after fallows occupied by clover, sainfoin, vetch-oat mixture, pea, and early potato. In the drier parts of the forest-steppe, for seed purposes wheat crops are better placed after black fallow.

In flax-growing regions, winter wheat can be placed after flax provided it is harvested early. In the Right-Bank Ukraine, the best predecessors are sugar beet stecklings and winter rapeseed.

On sandy and poor soils, the predecessor can be green-manure lupine fallow or occupied lupine fallow for feed with subsequent incorporation of crop residues.

On sandy and sandy loam soils of Belarus, Ukraine, and the central regions of the Non-Chernozem zone, green-manure fallows are suitable as predecessors, most often occupied by lupine, which is incorporated in the blue-green bean phase.

In regions of sufficient and unstable moisture, for example, in the North Caucasus and the Central Chernozem zone, due to relatively mild winters, although with unstable snow cover, favorable conditions for overwintering winter crops more often develop. Summer is usually warm and humid. The highest yields of winter crops are obtained after clean, occupied, green-manure, and coulisse fallows.

In experiments of Voronezh Agrarian University, it was established that grain harvest in the Central Chernozem zone in crop rotation after clean fallow is 1.0-1.3 t/ha higher than after fallow occupied by maize.

The Middle and Lower Volga region is characterized by a harsh continental climate with dry autumn, little-snow winter, sharp temperature fluctuations in spring, and dry summer. Under these conditions, occupied fallows and non-fallow predecessors do not allow accumulating enough moisture for winter crops. Therefore, black and coulisse fallows are preferable.

In the steppe part of the Trans-Volga region, good yields are possible only after clean cultivated fallows, with snow retention measures. In the forest-steppe part of the Right-Bank Volga region, in addition to clean and coulisse fallows, annual grasses and maize for green mass can be good predecessors. Long-term experiments of Voronezh Agrarian University (Fedotov A. V., 1998) showed that the yield of winter wheat in the steppe and forest-steppe zones when using coulisse crops is 1.5 times higher.

The Non-Chernozem zone is characterized by sufficient moisture, and in the northwestern regions by excessive moisture. In the west, winter is usually warm; in the central part it is colder; in the east it is severe. Snow cover falls early, and its thickness reaches 30-50 cm. Soils are low-fertile, loamy and sandy loam of varying degrees of podzolization, often requiring cultivation. In this zone, the optimal predecessors of winter wheat are occupied and green-manure fallows, perennial and annual grasses, maize for green fodder, pea for grain, and early potato. After clover, wheat gives the same yield as after clean fallow.

Fertilizer system

Winter wheat is demanding as to soil fertility and responsive to fertilizers on all soil types. To produce 1 c of grain and the corresponding amount of straw (1.5 c), it uses on average 3.7 kg of nitrogen, 1.3 kg of phosphorus, and 2.3-2.5 kg of potassium. The return of 1 kg of fertilizer nutrients by an increase in grain yield can reach 10 kg. Micronutrient fertilizers are also effective for winter wheat: manganese, zinc, boron, and copper.

According to data of the Mironov Research Institute of Wheat Breeding and Seed Production, the yield of the Mironovskaya 808 variety when sown after pea without fertilizers was 37.2 c/ha, whereas with the application of N₆₀P₆₀K₆₀ it was 42.6 c/ha. With continuous sowing of the same variety without fertilizers, the yield was 13 c/ha, and with the application of N₆₀P₆₀K₆₀ it was 25 c/ha.

In experiments of the Krasnodar RIA, the yield of winter wheat of the Bezostaya 1 variety when sown after maize for silage without fertilizer was 29.8 c/ha, whereas with the application of N₉₀P₄₅K₄₅ it was 48 c/ha. The yield increase per 1 kg of active ingredient of fertilizer was 10.1 kg.

Fertilizers, especially organic ones, are of particular importance on poor podzolized soils of the northern and central regions of the European part of Russia.

When calculating application rates for the planned yield, data from agrochemical cartograms, nutrient removal, and the coefficient of nutrient use by the crop from soil and applied fertilizers are taken into account. Rates are set taking into account meeting the plant need for the nutrient element whose deficiency may lead to insufficient use of other elements. Good results are achieved with split fertilizer application, especially on podzolized and leached chernozems and in the zone of sufficient moisture, when the main part is applied during plowing, part during pre-sowing treatments, at sowing, and as top dressing during the growing season.

The maximum nitrogen consumption by winter wheat occurs in the phases of stem elongation and heading. With optimal nitrogen nutrition during this period, the ear develops well and the number of spikelets increases. Nitrogen nutrition increases the protein content in grain.

Winter wheat intensively absorbs phosphorus during the first 4-5 weeks of growth. It has a great influence on accelerating crop ripening and increasing the size and volume of the root system, especially in the early stages of development: it promotes uniform emergence and rapid root system formation. The greatest phosphorus consumption occurs in the first 30-35 days after seed germination; thereafter its consumption occurs evenly. Phosphorus fertilizers should be applied for the main treatment and in rows.

Potassium is absorbed more intensively during the period from the first days of growth to flowering. It contributes to better overwintering, increases resistance to diseases and pests, and affects stem strengthening. Its consumption continues for a short time in spring after growth resumes. Potassium fertilizers should be applied in autumn for the main treatment.

Optimal phosphorus-potassium nutrition at the beginning of growth provides favorable conditions for plant rooting and accumulation of sugars in tissues, protecting them from freezing. Increased nitrogen nutrition in the first periods of growth and development, on the contrary, reduces resistance to freezing and smothering.

Nitrogen fertilizers are applied in autumn when wheat is placed after non-fallow predecessors and occupied fallows. Nitrogen is especially needed by winter wheat in spring. If sufficient nitrogen nutrition is provided at this time, plants quickly start growing, tiller well, and form many productive stems.

Liming is an effective measure on acidic and peat soils. On poor soils, lime fertilizers are applied together with phosphorus and organic fertilizers. On acidic peat soils rich in organic matter, lime is applied together with phosphorus-potassium fertilizers. Lime doses are calculated for full hydrolytic acidity and, as a rule, amount to 4-9 t/ha.

Soil cultivation system

Main page: Soil cultivation for winter crops

Soil cultivation system is developed taking into account the preceding crop, field weed infestation, and cultivation region. Winter wheat is responsive to plowing depth. Deepening of the arable layer is carried out during autumn plowing for the predecessor with simultaneous application of organic fertilizers in increased rates. On sod-podzolic soils with a shallow arable layer, good results are given by loosening of the subarable horizon or its plowing-in. The depth of plowing-in is determined by the thickness of the arable layer, soil podzolization, and organic fertilizer application rates.

Deepening of the arable layer increases water reserve, aeration, nitrate and soluble phosphate content.

The conditions for obtaining high yields of winter wheat after occupied fallow are high agricultural technology of the fallow-occupying crop and its timely harvesting. After harvesting continuous-sowing crops, depending on soil compaction, cultivation is carried out with plows with skimmers and simultaneous harrowing or cultivation. After harvesting row crops, the field is cultivated and harrowed.

In years with a dry summer-autumn period, surface treatment with disk or hulled harrows without moldboards with simultaneous harrowing and rolling is more effective. The exception is heavy soils in granulometric composition, prone to silting, and fields infested with root-sprouting weeds.

A large gap between harvesting the predecessor and cultivation is not allowed, since the soil during this time can become very dry. According to the data of the Mironovsky НИИ of Wheat Breeding and Seed Production, the yield of winter wheat when plowing immediately after harvesting corn for silage on August 10 was 63 c/ha, August 20 — 49.4 c/ha, and September 1 — 43.4 c/ha.

Treatment of black fallow begins immediately after harvesting the preceding crop. If stubble is present, a single harrowing to a depth of 6–8 cm is carried out. When fields are infested, disking to a depth of 6–8 cm and share harrowing to 12–14 cm are carried out. After 2–3 weeks, plowing to a depth of 25–27 cm is performed with plows with skimmers. To combat weeds and accumulate moisture, in the spring-summer period, 4–6 layer-by-layer cultivations of different depths are carried out from 10–12 cm, reducing to 5–6 cm. In dry weather, cultivation with rolling is carried out simultaneously.

With flat-cut soil treatment, herbicide treatment is included to combat weeds.

On early fallows, plowing is carried out in spring until May 15 to a depth of 20–22 cm; further treatment is similar to the treatment of clean fallows. Occupied fallows are treated depending on weather conditions and preceding crops. With moist, well-crumbling soil, ordinary plowing to a depth of 18–20 cm is used. On dry soil, surface treatments are carried out, for example, BDT-7.0, BD-10, BDT-3.0, LDG-5A, LDG-10A, LDG-15A, LDG-20A, KPE-3.8A.

In the Non-Chernozem zone, once every 3–4 years, plowing is replaced by deep chiseling to 35–45 cm to loosen the plow pan.

In dry years, after sowing winter wheat, soil rolling is carried out with simultaneous light harrowing. Rolling promotes uniform emergence, normal development, and eliminates the possibility of soil settling, improving overwintering conditions.

After spike predecessors, plowing is carried out as early as possible. Early plowing with simultaneous harrowing helps preserve moisture in the soil and reduce cloddiness. Before sowing, if weeds appear, 2–3 cultivations with harrowing are carried out. The first cultivations should be deeper; the pre-sowing one — to the depth of seed sowing. This method of soil treatment after spike crops approaches the treatment of clean fallows and is called semi-fallow soil treatment (semi-fallow); it is especially widely used in the south.

In a number of regions, large areas of land are at risk of wind erosion. For example, in the steppe regions of the North Caucasus, southern Ukraine, and the insufficient and unstable moisture zone of the Central Chernozem zone, strong winds lead to destruction and blowing away of soil, cause dust storms, damaging winter crop sowings and often leading to complete death of the crop. Therefore, in these regions, an anti-erosion soil cultivation system is used.

The anti-erosion soil cultivation system is widely used in Northern Kazakhstan and Western Siberia. It consists of non-moldboard (flat-cut) treatment with preservation of most of the crop residues on the soil surface. For non-moldboard treatment, flat-cutters of the KPG-250A, KPSH-9 types are used, which cut the roots of plant residues and loosen the soil to a depth of 8–30 cm; cultivator-deep-loosener KPG-2.2; rod cultivator KSH-3.6A, intended for soil treatment to a depth of 5–10 cm; needle harrow of the BIG-3A type for loosening, which hardly damages stubble. Sowing is carried out with a stubble seeder SZS-2.1, which simultaneously with sowing cuts weeds with cultivator shares and rolls the soil in the sown rows.

In all zones of the country, predecessors should free the field as early as possible. Thus, in the Non-Chernozem zone — 3–4 weeks before sowing, in southern regions — 1.5–2 months, for good soil preparation. After peas, corn for silage, and other predecessors, fields are treated as they are freed with disk implements of the BD-10A, BDT-7.0, LDG-10A types to a depth of 8–10 cm or flat-cut cultivators KPSH-9, KPG-2.2 to 10–16 cm. After peas, both methods are used; after corn, the first method is preferable, which is performed with heavy disk harrows in 2–3 passes followed by treatment with needle harrows BIG-3A and ring-spur rollers. It is important to observe the timing, not allowing gaps.

In dry years, it is effective to use combined units RVK-3.6, AKP-2.5, which in one pass loosen the upper layer by 6–8 cm with needle or spherical disks; the lower layer by 8–16 cm — with flat-cutters, followed by leveling the surface with a drag-harrow and roller.

After perennial grasses, harrowing is carried out, then plowing to a depth of 20–22 cm with plows with skimmers with simultaneous rolling with ring-spur rollers (ZKKSH-6) or plows equipped with PVR-2.3 or PVR-3.5 attachments.

Pre-sowing soil preparation consists of loosening the surface layer to a finely cloddy state and leveling. Treatment is carried out at an angle to the direction of the main treatment with shuttle movement of the unit. Pre-sowing treatment is carried out with flat-cutting working bodies to a depth of 5–6 cm with harrows and trails to reduce moisture loss and improve sowing quality.

Sowing

Crop care

The main methods of caring for winter wheat crops include rolling, top dressing, snow retention, spring harrowing, and control of weeds, pests, diseases, and lodging.

When sowing winter wheat in insufficiently moistened or loose, unsettled soil, rolling is carried out with ring rollers ZKKSH-6. Rolling promotes better contact of seeds with soil and movement of moisture from lower layers to upper ones, which favors rapid and uniform emergence and good autumn tillering. According to the data of the Krasnodar НИИСХ, this technique increased yield by 2.2 c/ha. To reduce the danger of damage to overgrown winter wheat, plants, if they are not prostrate, are mowed in autumn by one third of their height. The mowed green mass is immediately removed from the field to avoid the development of mold on plants. Mowing is carried out in a timely manner so that plants can strengthen before the onset of stable cold. Grazing of livestock on winter crops is not allowed.

In the northwestern regions of the Non-Chernozem zone, frequent autumn rains can greatly overmoisten the soil. Prolonged water stagnation in fields can lead to autumn waterlogging of crops. To prevent waterlogging and remove excess moisture, furrows are made in fields at a slight slope.

In autumn, after vegetation stops, to prevent the development of snow mold and root rots, crops are treated with fundazol at a rate of 0.3–0.6 kg of preparation per 1 ha.

An effective method of snow retention in steppe and forest-steppe regions is field-protective forest belts; in arid and low-snow regions — coulisse fallows. On average, snow retention increases winter wheat yield by 35% (0.4–0.7 t/ha). As coulisse plants, tall plants are used, for example, sunflower, mustard, southern hemp. These crops are sown in fallow 1–1.5 months (July 15–20) before sowing winter wheat with row spacing of 60–70 cm, 2–3 rows. The distance between coulisse rows is 10–20 m perpendicular to the direction of prevailing winds in winter. The seeding rate for sunflower is 20–25 seeds per 1 linear meter, for hemp — 40–50 fruits.

Coulisses can be sown along the future technological track; in this case, sowing is carried out along the coulisses, and in spring the technological track is rolled along them. Coulisses increase winter wheat yield by 0.3–0.5 t/ha.

To prevent the formation of an ice crust and prevent waterlogging in spring, pre-emergence slotting is carried out with the ShchN-2-140 unit, which reduces runoff and increases moisture reserves in the soil.

Spring harrowing is performed to destroy the soil crust, remove dead and damaged plants, as well as weeds, which can serve as a source of pest and disease spread. Harrowing begins after the soil surface has dried somewhat. Harrowing is carried out across the rows or diagonally. On poorly developed crops and light soils, harrowing is done in one pass; on well-developed crops and heavy soils — in two passes. Spring harrowing increases yield by 2–3 c/ha. In case of plant heaving, instead of harrowing, rolling is carried out.

Top dressing of winter wheat is carried out with nitrogen fertilizers in 2–3 applications: in early spring — at the beginning of vegetation, at the tillering phase — root, and at the earing phase — to improve grain quality.

Plant protection system

To develop a plant protection system, a phytosanitary assessment of crops is carried out. In intensive agricultural technologies, an integrated protection system is used, providing for the complex application of organizational-economic, agronomic, biological, and chemical methods. In the integrated protection system, the leading role is assigned to agronomic control measures. Chemical control methods are used as an additional measure. It is necessary on crops with severe weed infestation (more than 20 annual and one perennial species per 1 m²).

The development of winter wheat in spring proceeds slowly, so crops are easily overgrown with weeds. Chemical methods are used to combat it. In autumn, spraying is carried out after sowing before emergence with simazine at a rate of 0.25 kg/ha of a.i.

On winter wheat crops, herbicides of the 2,4-D group are used, for example, 40% amine salt at a rate of 1.5–2.5 kg/ha, granular butyl ester 10–12 kg/ha, as well as dialen 1.9–3 kg/ha. Treatment of crops is carried out in spring at the tillering phase at an air temperature of 12 to 25 °C; the solution consumption rate for ground spraying is 200–400 l/ha and 25–50 l/ha for aerial spraying.

To combat lodging of crops, treatment with the preparation tur is carried out at the tillering — beginning of stem elongation phase at a rate of 3–4 kg/ha of a.i. For example, treatment of winter wheat crops of the Mironovskaya 808 variety with the preparation tur at the Field Husbandry Experimental Station of the МСХА named after K. A. Timiryazev increased yield by 2.5–8 c/ha.

Diseases of winter wheat include: brown, yellow, and linear rust, loose and common bunt, root rots; pests — cereal (Hessian and Swedish) flies, shield bugs (Scutelleridae spp.) (Scutelleridae spp.), grain beetle. To combat diseases and pests, the following are effective:

• introduction of resistant varieties;
• against rust — treatment of crops with bayleton at a rate of 0.5–1 kg/ha or zineb 3–4 kg/ha at the tillering — stem elongation phase;
• against the shield bug and grain beetle, crops are sprayed with chlorophos 0.75–2 kg/ha or metaphos 0.5–1 kg/ha or volaton 2 kg/ha. During vegetation, 2–3 treatments are carried out, the last — no later than 15 days before harvesting.

The last treatment with any preparation should be carried out no later than 20 days before harvesting.

Harvesting

When the grain reaches the dough state, regular observations of the state of plants in the field begin. Ripening dates are determined by many factors. Thus, in hot and dry weather on sandy and sandy loam soils, on southern, southeastern, and southwestern slopes, ripening occurs earlier. For operational decision-making on harvesting, 50–100 plants are taken daily in different parts of the field, which are threshed and analyzed.

The start date of harvesting is determined taking into account moisture, external signs, and consistency of grain, and staining of the ear with eosin. The most objective indicator of grain ripeness is moisture. Wax ripeness of grain occurs at a moisture content of 35–40%, while the optimal period for starting two-phase harvesting is considered to be a decrease in moisture from 35 to 20%.

During analysis, external signs and consistency of grain are taken into account. At the beginning of wax ripeness, it becomes yellow, resembles wax, is easily cut with a fingernail, but is not crushed. At this time, in the field, all plants acquire a yellow color; green color is partially preserved only at the upper nodes of the stems.

Grain ripeness can be determined using eosin.

To make a decision on starting harvesting, at least 70–75% of the total amount of grain must be in the ripeness phase. The ability of grain to ripen in windrows as a result of reutilization of plastic substances from stems, leaves, and ears is an advantage of two-phase harvesting.

For high-quality harvesting, it is necessary to ensure modern labor organization, stable equipment productivity, and the availability of qualified specialists.

Harvesting of winter wheat accounts for 50–60% of the total costs of its cultivation. In the forest zone, this percentage is higher; in the steppe — lower, which is explained by the complexity and labor intensity of the process. Delay in harvesting after the onset of full ripeness leads to increased grain losses.

Biological yield — the amount of grain that was formed by the crop at the wax ripeness phase before the start of harvesting. It is determined on small plots (0.25 m²; 0.5 m² or 1.0 m²).

Actual, or barn, yield — the obtained grain harvest after completion of harvesting. The maximum biological yield of high quality is formed in the middle and at the end of wax ripeness at a grain moisture content of 35–20%. During this period, separate harvesting begins, the duration of which should be 5–7 days.

These indicators are also preserved in the full ripeness phase at a moisture content of 20–15% for 5–6 days after onset. During this period, direct combining should be completed. Premature or late harvesting leads to a decrease in the amount and quality of the yield. In this regard, 2–3 days before the start of harvesting, a control threshing is carried out. After that, field edges are mowed 25–30 m from the edge, with simultaneous division into paddocks.

2–3 days before the main harvesting, plant samples are taken along the field diagonals and analyzed for uniformity in grain lot quality to prevent their mixing at the threshing floor. For this, grain samples of 1–2 kg are taken from selected sheaves or control threshings.

Domestic combines of the Don-1500B; Yenisei-1200; Kedr-1200; Don-091; Don-161; SK-10V "Rotor"; Don-2600; PN-100 "Prostor" types have a fully mechanized grain harvesting process (mowing, threshing, cleaning, windrowing or chopping and spreading straw). However, on high-yielding fields, their use is associated with large losses. Foreign combines have a number of advantages.

In the steppe and forest-steppe zones, the greatest grain harvest is achieved by two-phase harvesting in the middle and at the end of wax ripeness, when the maximum biological yield has been formed, but the grain is still held in the ear. This period is the best harvesting time, but its duration is 2–3 days.

It is impossible to harvest all areas in such a short time. If two-phase harvesting is carried out at the beginning of wax ripeness, the yield decreases somewhat because reutilization of nutrients from vegetative organs for grain formation has not been completed.

Single-phase harvesting in the first 3–5 days of full grain ripeness does not lead to large losses. Delay in harvesting by this method, that is, 10–15 days after the optimal time, can lead to losses of up to 20–30% of grain. Therefore, with large areas of cereal crops, harvesting begins by the two-phase method at the beginning of wax ripeness and continues until the end of the phase. Upon reaching full ripeness, they switch to the single-phase method. Under favorable weather conditions, due to the greater productivity of the two-phase method, it is possible to harvest the main areas before the onset of full ripeness. The remaining smaller part of the areas can be harvested at optimal times.

This method is used for short, sparse, and overstayed crops, short-stemmed varieties resistant to lodging, as well as in regions with increased humidity during the harvesting period. The cutting height is set for short and lodged crops — no more than 10 cm; for long-strawed and lodged — 15–20 cm.

Two-phase harvesting is used for tall, unevenly ripening varieties prone to lodging and shattering, as well as on weedy crops. The stand density should be at least 250–300 plants per 1 m². The cutting height is set at 12–25 cm. In regions with increased humidity, thin wide windrows are formed; in dry ones — not wide thick ones. Mowing is carried out across the rows for better placement of stems in windrows. Two-phase harvesting is especially important in regions with a long period of cereal ripening and a short harvesting period.

Despite the advantages of two-phase harvesting, it must be rationally combined with single-phase. Thus, in bad weather during the harvesting period, direct combining is preferable, since under these conditions ears on the root dry faster than in windrows.

In two-phase harvesting, winter wheat is mowed with headers, for example, ZhVN-6A, ZhVR-10, ZhNS-6-12, ZhNU-4.0, ZhSB-4.2, and laid in windrows on stubble. At a stubble height of 15–20 cm, optimal conditions are created for blowing through the windrows. In tall cereals, the stubble height can reach 18–22 cm; in denser ones — 12–15 cm. Windrows should not touch the ground. The width of windrows should be up to 1.6–1.7 m; thickness in the south of the country — up to 25 cm, in moist conditions — up to 15–18 cm.

Stems in windrows should be located at an angle of 10–30° to the longitudinal axis. In certain regions of Russia, the duration of drying of windrows varies: for the North Caucasus and Southern Volga region — 2–3 days, in the Central Chernozem zone and Middle Volga region — 3–4 days, in the Non-Chernozem zone and Urals — 5–7 days.

In rainy and cloudy weather during harvesting, the drying duration increases by 2–3 days. Cereals cannot be left in windrows for a long period, since yield and quality decrease. Windrows are dried to a grain moisture content of 18–16%, since it continues to decrease later during threshing, transportation, and reloading. Strongly overdried grain can be damaged during threshing.

Under favorable weather conditions during harvesting, and if crops have not lodged, grain losses behind the header, during pickup and threshing are minimal. Crushing of seed grain is allowed no more than 1%, food and feed — no more than 2%.

The productivity of headers is 2 times higher than that of combines operating by the single-phase method. However, the productivity of combines when threshing windrows is 25–30% greater than direct combining.

The use of single-phase and two-phase harvesting methods, as well as the specific details of harvesting operations, require a qualified approach with sufficient practical experience. Their optimal combination is found at each specific enterprise and under various weather conditions. Thus, two-phase harvesting cannot be used on short, sparse, and low-productivity crops. This method must be used with caution in rainy weather, on tall crops, since the windrows will not dry. At the same time, on heavily weedy fields, two-phase harvesting is used.

Straw and chaff should be removed immediately after threshing, which allows the field to be quickly freed for subsequent operations. Depending on natural-climatic conditions and farm capabilities, straw removal is carried out in loose or pressed form. Due to the reduction in the use of organic and mineral fertilizers, part of the straw during harvesting of cereal crops is used in chopped form as organic fertilizer.

When harvesting winter wheat, as well as other cereal crops, harvesting-transport complexes are used, including units:

• for preparing fields for harvesting — mowing and swathing in areas, preparing headland strips;
• combine-transport — mowing, pickup and threshing of windrows or direct combining, collection and transportation of grain, chopped straw and chaff to storage sites;
• for technical maintenance — ensuring equipment readiness;
• for harvesting the non-grain part of the crop — dragging and stacking straw, pressing straw from windrows and its transportation;
• for primary soil treatment — harrowing and plowing of cleared fields.

Cultivation under irrigation

Cultivation of winter wheat under irrigation significantly increases gross grain harvests. For example, the Rostov Experimental Reclamation Station obtains 60 c/ha of grain on irrigated lands. In Kabardino-Balkaria, on irrigated lands, the average yield over a number of years reaches 42.8 c/ha; without irrigation — 5.2 c/ha. Modern varieties under irrigation conditions are capable of yielding up to 8 t/ha. Such results were obtained at the All-Russian НИИ of Irrigated Agriculture. However, the average yield under these conditions remains about 4 t/ha.

Under the conditions of the Southeast, steppe regions of the North Caucasus, and southeast of Ukraine, one of the tasks of winter wheat cultivation is obtaining uniform seedlings and its good development in autumn. For successful development of winter wheat, pre-sowing (moisture-charging) irrigation is important. Moisture charging of the soil in the non-vegetation period at a water consumption rate of 800–1500 m³/ha ensures high yield.

At the Stavropol Breeding and Experimental Station, on average over 6 years, the yield of winter wheat was 46.7 c/ha after moisture-charging irrigation, without irrigation — 24.9 c/ha.

The greatest effect from pre-sowing irrigation is achieved in years with a dry autumn and wet spring of the following year. Conversely, with a wet autumn and dry spring, vegetation-period irrigations surpass pre-sowing irrigation in effectiveness.

Moisture-charging irrigation can be carried out before plowing or after. Pre-plowing irrigation accelerates germination of weed seeds and promotes their growth. Germinated weeds are destroyed by subsequent deep plowing. This method increases the irrigation period, thereby reducing work tension and more effectively using canals and structures.

Moisture-charging irrigations begin several weeks before sowing and end at such times that enough time remains for pre-sowing soil treatment and sowing at optimal times. Despite their great importance, irrigations allow obtaining only average yields of winter wheat. The best results are given by a combination of moisture-charging and vegetation irrigations.

At the Grozny Experimental Reclamation Station, the yield of winter wheat on average over 4 years was: without irrigation 10.2 c/ha, with moisture-charging irrigation — 21.6 c/ha, with moisture-charging irrigation and two vegetation irrigations — 34.6 c/ha, with 2–3 vegetation irrigations — 25.5 c/ha.

Varieties of winter wheat

Aly Parus. Durum wheat variety. Mid-season, winter-hardy, drought resistance high. Resistant to lodging and shattering. Pasta quality satisfactory. Zoned in the North Caucasus.

Mironovskaya 808 (v. lutcscens). The variety was developed at the Mironovsky НИИ of Wheat Breeding and Seed Production by Academician V. N. Remeslo. The variety was obtained from spring wheat Artyomovka. Mid-season, winter-hardy, relatively drought-resistant. Resistant to shattering, weakly resistant to lodging. Resistance to brown rust is not high. Grain quality excellent, grain large, vitreous. Baking qualities good. High-yielding, belongs to strong wheats. Widely zoned.

Bezostaya 1 (v. lutescens). The variety was developed at the Krasnodar Research Institute of Agriculture (НИИСХ) by Academician P. P. Lukyanenko. Mid-early. Winter hardiness and drought resistance average. Resistant to shattering and lodging. Weakly affected by brown, yellow, and stem rust, loose smut. Responsive to fertilizer and irrigation. Grain has good baking qualities. High-yielding, belongs to strong wheats. Widely zoned.

Odesskaya 51 (v. erythrospermum). The variety was developed at the All-Union Selection and Genetic Institute. Early ripening. Drought resistance and winter hardiness good. Resistant to lodging and shattering, brown and yellow rust. Baking qualities good. Zoned in the south and southeast of Ukraine, in Moldova, Kalmykia.

Polesskaya 70 (v. erythrospermum). The variety was developed at the Ukrainian НИИ of Agriculture (NIIZ). Mid-season. Zoned in Vinnitsa, Ivano-Frankovsk, Khmelnitsky, Volyn, Kiev oblasts.

Severodonskaya (v. lutcscens). The variety was developed by the Zernograd State Breeding Station and the North-Donetsk Agricultural Experimental Station. Mid-early, winter-hardy, drought resistance high. Resistant to lodging. Baking qualities good and excellent. Zoned in Voronezh, Rostov, Lugansk and other oblasts.

Akhtyrchanka (v. lutescens). The variety was developed at the Ivanovo Experimental Breeding Station of VNIS. Mid-early, winter-hardy, medium-resistant to lodging. Baking qualities good. Zoned in Sumy and Cherkassy oblasts.

Moskovskaya 39. Mid-season variety, high yield. Resistant to lodging, brown rust, common bunt, winter hardiness high. Baking qualities high. High protein content — 1.5–2% higher than other zoned varieties, gluten — by 6–8%. Zoned in the Non-Chernozem zone.

Zarya (v. lulescens). The variety was developed at the НИИ of Agriculture of the Central Regions of the Non-Chernozem Zone. Mid-season, winter-hardy, medium-resistant to drought and lodging. Baking qualities satisfactory and good. Zoned in Ivanovo and Moscow oblasts.

Inna. Mid-season variety, winter-hardy and frost-resistant. Resistant to lodging, common bunt, powdery mildew, yellow rust. Baking qualities satisfactory and good. Yield 4–5 t/ha. Zoned in the Central Chernozem and Non-Chernozem zones.

Pamyati Fedina. Mid-season variety, winter-hardy. Resistant to lodging, yellow rust, common bunt, septoria, powdery mildew. Baking qualities good and satisfactory. Zoned in the Non-Chernozem zone.

Parus (v. leucurum). Durum wheat variety developed by the All-Union Selection and Genetic Institute. Mid-early, winter hardiness average, drought resistance high. Resistant to lodging. Pasta quality satisfactory. Zoned in Odessa and Kherson oblasts.

Odesskaya yubileinaya (v. leucurum). Durum wheat variety, developed by the All-Union Selection and Genetic Institute. Mid-early, winter hardiness average, drought resistance high. Resistant to lodging, shattering, brown and yellow rust. Pasta quality good. Zoned in Nikolaev and Odessa oblasts.

Smuglyanka. The variety is drought-resistant and winter-hardy. Baking qualities good. Resistance to common bunt and brown rust high; resistant to powdery mildew. Zoned in the Middle and Lower Volga regions.

References

1. Vavilov P. P., Gritsenko V. V., Kuznetsov V. S. et al. (1986). Crop Production. Ed. Vavilov P. P. 5th ed., revised and enlarged. Moscow: Agropromizdat.

2. Kolomeichenko V. V. (2007). Crop Production/Textbook. Moscow: Agrobusinesscenter.

3. Niklyaev V. S. (2000). Fundamentals of Agricultural Production Technology. Agriculture and Crop Production. Moscow: Bylina.