Home » Horticulture

Category Archives: Horticulture

Maral root

Leuzea safflower-like (Rhaponticum carthamoides, also “maral root”) is a medicinal plant.

Economic importance

The rhizomes and roots of Leuzea safflower contain alkaloids, tannins, essential oils, resins and mineral salts, ascorbic acid. Roots and rhizomes are used to obtain extracts and tinctures that have a stimulant in physical, mental and mental overwork. They can be used to increase efficiency, appetite, sexual
potency, etc.

Leuzea safflower is a promising fodder plant for the forest-meadow and forest-steppe zones of Russia. The yield of green mass reaches 30-35 t/ha. The green mass is suitable for the preparation of silage, haylage and vitamin-grass flour. Plants are readily eaten by farm animals in their pure form and in mixtures with other herbs. In terms of protein content, Leuzea safflower is not inferior to legumes. Due to the high content of sugars, it is suitable for ensiling both in pure form and in mixtures with various fodder crops, such as corn, annual grasses.

100 kg of green mass of safflower leuzea correspond to 15 feed units and contain 2.1 kg of digestible protein; 1 feed unit accounts for 140 g of protein. 100 kg of silage correspond to 16.5 feed units and 2.1 kg of digestible protein; 1 feed unit accounts for 127 g.

The inclusion of leuzea feed in the diet has a positive effect on the reproductive ability of animals.

Good honey plant.

Crop history

Leuzea safflower has long been known in Mongolia. Until now, it is believed that this plant can cure 14 diseases and give a person strength up to 100 years.

Habitats

Plants of the genus Leuzea are distributed mainly in the Northern Hemisphere.

In Russia, the range of Leuzea species mainly extends to the mountains of Altai, Kuznetsk Alatau, Sayan, etc.

Botanical description

Leuzea safflower-like (russian), or safflower-shaped raponticum (Raponticum carthamoides Willd) is a perennial rhizomatous plant of the Asteraceae family.

The genus Leuzea includes 17 species, 14 of them grow in Russia.

The tap root, gradually thickening, has numerous branches, penetrates the soil to a depth of 80 cm, forms a powerful branching rhizome.

Stem erect, irregularly rounded, hollow, slightly branched, slightly leafy. Plant height 130-180 cm.

Leaves sessile, in the lower part of the plants 70-90 cm long, 15-25 cm wide, in the upper part much smaller, deeply pinnately dissected, on long petioles.

The inflorescence is a dense, rounded basket, 5-8 cm in diameter. The flowers are bisexual, violet-lilac or pinkish.

The fruit is a purple-brown tetrahedral achene. Weight of 1000 pieces – 15-18 g.

Biological features

Leuzea safflower-like – a plant of winter type of development. In the first year of life, it forms a powerful rosette of leaves.

In the second and subsequent years, plant growth begins immediately after the snow melts. Flowering occurs in late May – early June. Fruiting occurs from the second year of life. After fruit ripening, generative shoots die off completely 1-1.5 months before the end of the growing season.

Leuzea begins to produce the largest yields of green mass from the third year of life.

It tolerates double use well. The proportion of leaves by the stage of cutting maturity reaches 60-70% of the total above-ground phytomass.

Leuzea safflower-like is a light-loving plant, therefore, sowing under the cover of other crops is not carried out.

Frost-resistant. Seedlings are able to tolerate early spring frosts down to -4 °C.

Leuzea is not very demanding on moisture, therefore it can be cultivated in the conditions of the forest-steppe zone. However, it does not tolerate waterlogging of the soil and prolonged flooding.

Highly fertile sandy and loamy, gray forest and chernozem, well-aerated soils with a slightly acidic reaction (pH 5.6-6.0) are considered optimal.

Agrotechnology

For the formation of 10 tons of green mass, the safflower-like leuzea removes 35.7-50.0 kg of nitrogen from the soil; 5.9-12.0 kg of phosphorus; 48.7-55.0 kg of potassium, 30.5-37.3 kg of calcium.

Leuzea is usually grown in non-rotational areas.

The best predecessors are annual grasses, tilled and leguminous crops.

When laying a plantation, 50-60 t/ha of organic fertilizers and lime are applied to the soil, the application rate of which is calculated from the total hydrolytic acidity.

After plowing, the field is cultivated.

In the case of late autumn sowing, the treatment is carried out with an РВК-3 unit. Sowing Sowing can be done in the fall 1-2 weeks before the onset of permanent frosts, but it is best to sow in the spring. Vegetable seeders with row spacing of 60-70 cm can be used for sowing. Sowing depth is 2-3 cm. Seeding rate is 6-10 kg/ha.

In the first year of plant life , 2-4 inter-row treatments are carried out for weed control , if necessary, herbicides are applied.

Mowing of the safflower-like leuzea in the first year of life is usually not carried out so as not to weaken the plants and not worsen overwintering.

In the second and subsequent years, inter-row cultivation is carried out on the plantation in early spring with simultaneous top dressing. The fertilizer application rate for top dressing is N45-60P45-60K45-60.

After the first mowing, a second inter-row processing is done with the simultaneous application of P20-30K20-30. Every 2-3 years it is recommended to apply rotted manure on the plantation at the rate of 15-20 t/ha.

Harvesting

When cultivating safflower-like leuzea to obtain vitamin-herbal flour, they start harvesting in the budding phase, for silage – in the flowering phase. To protect the bees, harvesting is carried out early in the morning and late in the evening.

Leuzea safflower-like allows two-fold mowing every year, while depletion of plants is not observed.

The second mowing is usually done in late August – early September.

For use any silo harvesters.

Leuzea seeds can be obtained from ordinary forage crops, starting from the third year of life. Harvesting for seeds begins when 70% of the inflorescences turn brown. For this, semi-mounted sorghum harvesters can be used. Cut inflorescences are dried and threshed on a current. After harvesting the inflorescences, the remaining mass is suitable for livestock feed.

Sources

V.V. Kolomeichenko. Crop production / Textbook. — M.: Agrobusinesscenter, 2007. — 600 p. ISBN 978-5-902792-11-6.

Melissa officinalis

Economic importance

Melissa officinalis is widely used as a medicinal, essential oil and vegetable plant. Young greens are used as a seasoning and for the preparation of tonic infusions. Due to the volatility of its delicate lemon flavor, lemon balm is added to ready meals. When dried, lemon balm gradually loses its aroma even in tightly closed containers.

The leaves contain essential oil, which is used in medicine, perfumery and the production of alcoholic beverages.

The aerial vegetative part (“grass”) has an analgesic and antispasmodic effect. Melissa infusions serve as an appetite stimulant, normalize the functioning of the gastrointestinal tract, relieve fatigue, have a calming and tonic effect on the nervous system, and help with insomnia and migraines. A decoction is used to rinse the mouth with inflammation of the gums, for the treatment of skin diseases.

For medicinal purposes, use the leaves collected in the budding phase. During this period, they contain up to 0.3% essential oil, as well as carotene and tannins. The seeds contain up to 20% fatty oil.

Crop history

Melissa officinalis has been known as a medicinal plant for over 2,000 years.

The homeland is the Mediterranean.

Habitats

Currently, lemon balm is grown in small areas in some countries of Europe, Asia, and also in the USA.

Melissa has been cultivated in Russia since the middle of the 20th century.

Botanical description

Lemon balm (Melissa officinalis L.) is a perennial herb belonging to the Lamiaceae family.

The root system is in the form of a strongly branched rhizome.

The stem is straight, tetrahedral, branched. Plant height reaches 1.0 m. Creeping in the lower and side shoots.

Leaves ovate, petiolate, light green.

The flowers are small, sessile, yellowish, pink or whitish. The inflorescence is a complex umbrella, located in the axils of the upper leaves.

The fruit consists of four nuts, brown or almost black. Weight of 1000 pieces 0.5-0.7 g.

Biological features

Melissa officinalis is a thermophilic and light-loving culture. Shading leads to a decrease in the content of essential oil in the leaves.

For normal growth and development, plants need sufficient moisture, but lemon balm does not tolerate excess water.

Prefers fertile, light-textured soils.

It has poor winter hardiness, therefore, in the northern regions it is grown only as an annual crop.

Agrotechnology

The best predecessors of lemon balm are perennial herbs , vegetables, winter grains and legumes .

Lemon balm plantations are usually planted for 3-5 years.

Soil preparation includes:

  • stubble peeling;
  • autumn plowing;
  • early spring harrowing;
  • deep preplant cultivation to a depth of 12-15 cm.

It is recommended to apply organic (20-30 t/ha) and mineral fertilizers for autumn plowing. In the second and subsequent years of plantation use, two fertilizing with nitrogen and phosphorus fertilizers is carried out during the growing season . Top dressing is given in early spring and after the first mowing.

Melissa officinalis is propagated by seed, seedling and vegetative methods. For vegetative propagation, parts of old bushes, layering and rhizomes are used. The layout of plants 60-70 × 30 cm.

Landing care includes:

  • 3-4 inter-row loosening;
  • 1-2 weeding;
  • top dressing;
  • 3-4 waterings.

Irrigation rate is 500-600 m3/ha. Watering is carried out in dry weather.

Cleaning and drying

During the summer, lemon balm is mowed 2-3 times. The yield of green mass in this case reaches 20-25 t/ha.

The selection of essential oil is carried out by steam distillation of freshly harvested raw materials. The yield of essential oil is usually 30-35 kg/ha.

To harvest lemon balm as a raw material for the food industry, the green mass is dried in the shade under sheds or in dryers at a temperature not exceeding +35 °C.

Harvesting of lemon balm for seeds is carried out in single-phase or two-phase methods. The yield of seeds is usually 200-300 kg/ha.

Sources

V.V. Kolomeichenko. Crop production / Textbook. — M.: Agrobusinesscenter, 2007. — 600 p. ISBN 978-5-902792-11-6.

Common hop

Economic importance

Common hop has long been used in many peoples of the world for various purposes.

For brewing purposes, this plant is cultivated on special plantations in many countries, for example, in the USA, England, Germany, Russia. The main raw materials are “cones”, which contain 16-26% bitter resinous and 3% tannins, as well as 0.4% essential oils.

In limited quantities, the “cones” of common hops are used for baking some types of bread. The young shoots are sometimes used for culinary purposes.

Common hop is important as a medicinal plant. It has properties that improve appetite and digestion, and is used in the treatment of kidneys and bladder, irritability and insomnia, gout, rheumatism, etc.

Crop history

The first mention of the use of common hop for medicinal purposes refers to the Arabs and dates back to the VIII century. AD Around the same time, it began to be grown in Europe.

Cultivation areas and yield

Currently, the area of ​​cultivation of cultivated and wild hops occupies a large territory in Europe and Asia Minor.

In Russia, hops are distributed almost everywhere in the European and Asian parts of the country. Hop is considered a plant of Russian forests and does not belong to specially protected species. In forests of different types, it is usually found scattered – one or several plants.

Botanical description

Hop (Humulus lupulus L.) is a perennial herbaceous vine belonging to the Cannabinaceae family.

The root system is taproot with horizontal underground rhizomes.

Above-ground shoots can reach 7 m in length.

Leaves opposite, heart-shaped.

Male flowers are small, yellowish-green, located in axillary paniculate inflorescences. Female inflorescences are collected in capitate inflorescences, resembling “cones” in appearance.

The fruit is a nutlet, brown in color.

Flowering in July-August, fruiting in August-September.

Biological features

Hop is a moisture-loving and heat-loving plant.

The sum of temperatures for its development averages about 2600 °C. The optimal average daily temperature is 16-18 °C.

The optimal amount of annual precipitation is 450-650 mm, relative humidity is 70-80%.

Common hop is demanding on soils. It develops well on fertile soils with a slightly acidic reaction. Chernozems, gray forest, light and loamy soils are considered the best. Sandy, carbonate and waterlogged soils are unsuitable.

From the soil, hops absorb 3.5-4 times more nutrients (NPK) than winter wheat.

Hops are considered a plant sensitive to zinc deficiency in the soil.

Agrotechnology

Typically, hops are grown on permanent plantations ranging from 3-4 to 30-40 hectares for 15-20 years. For the growth and development of plants, special trellises up to 7 m high are constructed to support the above-ground part.

Growing hops from seeds is only important in breeding work.

To propagate this culture, a vegetative method is used using cuttings that are cut from the underground parts of the stems. For accelerated reproduction, rhizomes and shoots can also be used.

In some cases, the cultivation of special seedlings in nurseries is practiced.

The planting scheme in commercial hop farms: 2.25 x 1.0 m or 2.5 x 1.2 m. At the same time, the density of plants per 1 ha is 4.4 and 3.3 thousand plants.

Hop care includes:

  • pinching;
  • tweezing of lateral branches;
  • chasing the tops of the bushes.

The main goal of care work is to limit the growth processes of the vegetative organs and enhance the formation of “bumps”.

Cleaning and drying

Harvesting of the “cones” of hops begins at technical ripeness, that is, when the green color changes to a lighter, yellow-green or golden green. In a state of technical ripeness, the “cones” have a strong smell of lupulin.

Cleaning must be carried out quickly, as the browned “bumps” lose quality. During harvesting, the “bumps” break off separately with a petiole no more than 2 cm.

The moisture content of the “cones” at the time of harvesting is about 80%, so they are immediately sent for drying in special hop dryers. During drying, the moisture content of the “cones” is brought to 8-9%, after which they are pressed, packed into a fabric weighing 15-16 kg.

Sources

V.V. Kolomeichenko. Crop production / Textbook. — M.: Agrobusinesscenter, 2007. — 600 p. ISBN 978-5-902792-11-6.

Strong tobacco

Strong tobacco (Nicotiana rustica, russian “makhorka”) is an alkaloid plant and industrial crop.

Economic importance

Strong tobacco is grown for smoking (shag) grits, snuff and chewing tobacco. For smoking purposes, shag is used much less frequently than tobacco .

Dried shag leaves contain 5-15% nicotine, 15-20% organic acids, including 7-14% citric and 3-4% malic acids. The stems of shag plants contain less of these substances.

The raw materials of shag are used in the pharmaceutical industry for the production of nicotinic acid (vitamin PP), the food industry for the production of citric acid and the textile industry.

Shag seeds contain 35-40% fatty oil, which is used in the manufacture of paints, varnishes and soaps.

Strong tobacco can serve as a raw material for the production of environmentally friendly insecticides. The soil and climatic conditions of many regions of Russia make it possible to significantly expand the sown areas of this crop.

Crop history

North America is considered the birthplace of shag.

Cultivation areas and yield

The cultivated area occupied by shag is much less than the cultivated area of ​​tobacco. It is cultivated in India, Algeria, Tunisia, Poland.

Strong tobacco is cultivated in the Central Black Earth zone of Russia, in Mordovia, Chuvashia, Tatarstan and Western Siberia, as well as in Ukraine.

In the USSR, the sown area of ​​shag was 10,000 hectares in the USSR.

Botanical description

Strong tobacco or makhorka (Nicotiana rustica L.) is an annual plant of the Solanaceae family. Not known in the wild. It is an interspecific hybrid from the natural cross-pollination of two wild species (Nicotiana undulata and Nicotiana paniculata).

Taproot, highly developed.

The stem is erect, ribbed, with a loose core. Plant height reaches 1.2-1.5 m.

The leaves are petiolate, fleshy, heart-shaped or ovate with a wrinkled surface, dark green, light green or yellow-green. The number of leaves per stem is a varietal characteristic and is usually 12-20.

In the axils of the leaves, lateral shoots are formed – stepchildren.

The stems and leaves are covered with short capitate hairs with a strong specific smell.

Inflorescence – panicle. The flowers are bisexual, green or yellowish-green, quintuple type, with bracts. Plants are self-pollinating, but cross-pollination is also noted.

The fruit is a bivalve (two-celled) multi-seeded box. In one box 200-600 seeds are formed. Seeds are small, brown or cream. Weight of 1000 seeds 0.25-0.35 g.

Biological features

Strong tobacco is less demanding on heat than tobacco. Germination of shag seeds begins at a soil temperature of 7-8 °C. The optimum temperature for growth and development is 20-25 °C.

Shag is sensitive to low temperatures, plants are damaged at a temperature of -2 … -3 °C.

Strong tobacco is demanding on moisture. Optimum soil moisture is 55-70% HB. The transpiration coefficient is 450-500.

Strong tobacco is a long day plant. With the advancement of its crops to the north, it accelerates its development, which allows it to be grown even in the Arctic.

Loamy chernozems, gray forest, sandy and loamy sod-podzolic soils are considered optimal for shag.

Vegetation

There are two periods in tobacco culture:

  • growing seedlings from seeds in greenhouses or soil ridges;
  • growing tobacco from seedlings in the field.

The seedling formation period usually lasts 45-50 days, but depends on the variety and usually ends by the time 5-6 true leaves appear.

The period from planting seedlings in the field to the onset of technical ripeness of the leaves of the upper tier lasts 80-120 days. Rooting of seedlings after its transplantation in the field is 10-15 days, after which the phases of stemming, budding, flowering, seed formation and maturation begin.

The formation of leaves in tobacco occurs in tiers.

Technological properties of leaves are determined by varietal characteristics, layering, growing conditions.

Crop rotation

The best predecessors of strong tobacco in the crop rotation are winter cereals, corn, root crops, legumes, annual and perennial grasses, vegetables.

Bad predecessors are gourds, potatoes (all solanaceous), hemp, sunflower, as they have common diseases and pests with it.

Strong tobacco serves as a good forerunner for many field crops.

Strong tobacco allows repeated crops.

Strong tobacco crop rotation

Among the strong tobacco crop rotations are used:

  • grass-rowed:
    • 1-2 – perennial grasses, 3-4 – strong tobacco, 5 – leguminous, 6 – strong tobacco, 7 – annual grasses with overseeding of perennial grasses – 42.7% strong tobacco;
    • 1 – clover , 2-3 – strong tobacco, 4 – corn for silage, 5 – strong tobacco, 6 – annual grasses with overseeding of perennial grasses – 50% strong tobacco;
  • tilled:
    • 1 – corn for silage, 2-3 – strong tobacco, 4 – grain legumes, 5 – strong tobacco – 60% strong tobacco;
    • 1 – annual herbs, 2 – strong tobacco, 3 – root crops, 4 – strong tobacco – 50% strong tobacco.

Fertilizer system

Strong tobacco consumes relatively few nutrients from the soil. For the formation of 100 kg of dry leaves and stems, it consumes 2.4 kg of nitrogen, 1 kg of phosphorus, 3.5 kg of potassium.

Strong tobacco responds well to the application of organic and mineral fertilizers. The application rate of manure depends on the fertility of the soil and is usually 40-60 t/ha. When combined with mineral fertilizers, the rate of manure is reduced.

The recommended application rates of mineral fertilizers to obtain a yield of dry leaves and stems of 3.0 t/ha on various soils are:

  • on sod-podzolic – 120 kg/ha of nitrogen 120, 60 kg/ha of phosphorus, 90 kg/ha of potassium;
  • on leached chernozems – 90 kg/ha of nitrogen, 60 kg/ha of phosphorus, 60 kg/ha of potassium;
  • on peatlands – 20 kg/ha of nitrogen, 90 kg/ha of phosphorus, 120 kg/ha of potassium.

Manure and 2/3 of the entire norm of phosphorus and potash fertilizers are applied in autumn under deep plowing. In the spring, for cultivation, when sowing or planting seedlings and for top dressing, all nitrogen fertilizers and the rest of phosphorus and potash are applied.

Before sowing shag, a mixture is prepared in the field, consisting of superphosphate, at the rate of 20-30 kg of phosphorus, and 5-10 times the amount of humus. Seeds are poured into the mixture and mixed well, after which they are sown.

When planting seedlings, superphosphate (20 kg of phosphorus) and nitrogen fertilizers (15-20 kg of nitrogen) are applied simultaneously with irrigation water. The remaining amount of mineral fertilizers is used as top dressing.

Tillage system

Autumn tillage for strong tobacco includes:

  • two peelings (after grain crops) with disc tools to a depth of 6-8 cm and 10-12 cm;
  • early deep plowing by 25-30 cm (Vavilov; according to other recommendations 20-22 cm, Kolomeichenko).

In the spring, plowing is harrowed and 1-2 cultivations are carried out, followed by harrowing and leveling the soil surface.

Growing methods

Strong tobacco can be grown in two ways: seedlings (seedlings) and sowing seeds in the field (seeding).

The seedling method is important for the northern regions of cultivation. This method is associated with an increase in the cost of growing seedlings and planting them. However, low-lying areas flooded with hollow water and insufficiently structured soils can be occupied under it.

Elevated areas with light structural soils are best suited for seedlings.

Growing seedlings (saplings)

Strong tobacco seedlings are grown in greenhouses or on soil ridges.

The seeding rate in greenhouses is 1.5-2 g/m2, on warm beds – 2-2.5 g/m2, on cold beds – 2.5-3 g/m2.

Before sowing, the seeds are subjected to dressing in a weak solution of formalin and germinated at a temperature of 25-28 °C for 3-4 days. Before sowing, the seeds are mixed with clean sand in a ratio of 1:40.

For planting 1 hectare of shag, depending on the varietal characteristics, there are 30-45 m2 of greenhouses or 45-60 m2 of warm ridges.

Seedling care

Seedling care involves maintaining the optimum temperature (18-20 °C), thinning plants, 2-3 feedings, watering and hardening.

Seedlings ready for planting should have 5-6 true leaves and a height of 8-12 cm. Growing seedlings in greenhouses usually takes 30-35 days, in ridges – 40-45 days.

Transplanting

Planting seedlings of strong tobacco is recommended to be carried out in the early stages, after spring frosts, when the topsoil warms up to 10 °C. For the south of Ukraine, landing begins in late April – early May, in the Central Black Earth zone of Russia – in the second decade of May, in the north of the Non-Chernozem zone and in Siberia – in the third decade of May – early June.

Planting of seedlings is carried out manually or with the help of transplanters with a row spacing of 50-60 cm and a distance between plants of 20-30 cm.

For large-leaved varieties of shag, the plant density is recommended to be 60-70 thousand/ha, medium-leaved – 70-80 thousand/ha, small-leaved – 80-90 thousand/ha.

A square-nest method of placing plants according to the 50 × 50 cm scheme can be used, while two plants are planted in a nest.

Sowing (seedling)

They start sowing strong tobacco at an early date, simultaneously with the sowing of early grain crops.

For sowing, a mixture of germinated and dry seeds is used in equal amounts. Germinated seeds germinate 6-7 days after sowing, dry seeds – after 15-18 days. This approach allows you to get good seedlings if early shoots from germinated seeds have suffered from frost.

The method of sowing shag is wide-row with row spacing of 50-60 cm. For sowing, special or grain seeders with depth limiters can be used. The seeding rate is 2-3 kg/ha. Seeding depth no more than 1 cm.

Landing care

Before the emergence of seedlings during the formation of the soil crust, its destruction is carried out with the help of rotary hoes.

The first loosening of row spacing is done at the beginning of emergence to a depth of 5-6 cm. The second loosening is carried out 8-10 days after the first to a depth of 6-8 cm.

Bouquet of crops begins in the phase of two true leaves. With a wide-row sowing method with row spacing of 60 cm, the width of the cutout is 20 cm, and the length of the bouquet is 10 cm, the distance between the centers of the bouquets should be 30 cm. After 2-3 days, the bouquets are thinned, leaving 3-5 well-developed plants in them.

The final breakthrough is done 10-12 days after bouquet, when the plants have 5-6 leaves. With a wide-row sowing method, one plant is left in each bouquet, with a square-nested method – two of the best. Simultaneously with thinning, the first top dressing is carried out.

The recommended planting density of shag seedlings is the same as seedlings: 60-70 thousand plants per ha for large-leaved varieties, 80-90 thousand/ha for small-leaved varieties.

After thinning, 2-3 loosening of row spacings and top dressing are performed.

Before the first or second inter-row treatment, the seedlings and seedlings are cleaned, that is, the removal of 2-3 lower leaves.

During budding, topping is done, that is, the removal of inflorescences, and when lateral shoots grow by 5-7 cm, pinching.

Harvesting and drying

Harvesting of shag is carried out in one step with whole plants at the onset of technical ripeness, which is characterized by brittle leaves and their sagging. At the same time, mature leaves emit a strong peculiar smell. Delay in harvesting shag can lead to damage to plants by autumn frosts.

To speed up the drying of ripe shag, its stems are cut from top to bottom (plastered) 3-4 days before harvesting, leaving the lower part of the stem 5-6 cm long intact so that the plants do not die. The layering method allows to reduce drying by 10-12 days and reduce the loss of dry matter.

The shag is harvested by hand in dry, sunny weather. For this, the plants are cut down at the root, leaving not even small stumps. Cut down plants are left in the field for drying. Drying is completed when the leaves become soft and will not break when bent.

From the field, shag is transported to drying rooms, where it is subjected to languishing at a temperature of 30-40 ºС for 20-24 hours. The width of the stack is made equal to the length of two plants, the height is 50-70 cm. After languishing, the shag is dried for 25-30 days in well-ventilated rooms. Drying is considered complete when a moisture content of 35% is reached.

Sources

Crop production / P.P. Vavilov, V.V. Gritsenko, V.S. Kuznetsov and others; Ed. P.P. Vavilov. – 5th ed., revised. and additional – M.: Agropromizdat, 1986. – 512 p.: ill. – (Textbook and textbooks for higher educational institutions).

V.V. Kolomeichenko. Crop production / Textbook. — M.: Agrobusinesscenter, 2007. — 600 p. ISBN 978-5-902792-11-6.

Tobacco

Tobacco (Nicotiana tabacum) is an alkaloid crop, also considered one of the most labor-intensive industrial crops.

Economic importance

Tobacco is grown for its leaves, which are used as a raw material in the manufacture of cigarettes, cigars and pipe tobacco.

Tobacco leaves contain:

  • nicotine 1-3%;
  • essential oils – about 1%;
  • resins – 4-7%;
  • proteins – 7-10%;
  • carbohydrates – 4-13%;
  • ash – 13-15%.

The smell and aromaticity of tobacco are due to resins and essential oils.

Nicotine is synthesized by the root system of tobacco plants. This was proven by Academician A.A. Shmuk in 1941 together with employees. If tobacco is grafted onto a tomato , then nicotine is practically not found in tobacco leaves, and, conversely, up to 3-4% of nicotine accumulates in tomato leaves grafted onto tobacco.

Tobacco also serves as a raw material in the pharmaceutical industry.

Crop history

Tobacco is native to America. The Indians of South and Central America used tobacco leaves for smoking long before Europeans discovered the continent.

Cultivation areas and yield

Tobacco is currently grown in many countries around the world. The sown area of ​​tobacco is more than 4 million hectares. More than half of the world’s production is in China, the United States, India and Brazil.

In the USSR, over 170 thousand hectares were occupied under tobacco crops. The main regions of cultivation are Moldova, the south and south-west of Ukraine, the countries of Central Asia and the Caucasus, in Russia – the North Caucasus. The average yield of tobacco is 1.5-2.0 t/ha. The maximum yields that could be obtained were 3.0-3.5 t/ha. For example, in the collective farm named after Krupskaya, Urgut district, Samarkand region of Uzbekistan, on an area of ​​1027 hectares, the yield reached 3.6 t per hectare with an output of 87% of the highest grades.

Botanical description

Tobacco (Nicotiana tabacum L.), or cultivated tobacco, is an annual plant belonging to the Solanaceae family. The genus includes about 70 species.

The root is taproot, penetrates the soil to a depth of 1.5-2 m. The stem is erect, pubescent. Plants reach 100-180 cm in height.

The leaves are large, petiolate or sessile, entire, oval, ovate or elliptical, pointed, with a smooth or wrinkled surface. The number of leaves on one plant reaches 25-50 pieces. Their number and size depend on the variety type and growing conditions. The leaves and stem are covered with short sticky hairs.

Inflorescence paniculate, corymbose. Flowers bisexual, pedicel, pentate, with bracts. The calyx is bell-shaped. The corolla is longer than the calyx, covered with hairs on the outside. The corolla tube is white, the limb is pink or red. The ovary is superior, often bilocular. The stigma is bilobed. Stamens five.

Tobacco is a self-pollinator, but cross-pollination is possible.

The fruit is a two-celled, multi-seeded, oval capsule, 1.5-2.0 cm long, brown, cracking when ripe. In one box, up to 5000 thousand seeds can be formed.

Seeds are oval, dark brown, very small. Weight of 1000 seeds (0.05) 0.06-0.08 (0.12) g.

In tobacco growing, two groups of tobacco are distinguished – cigarette and cigar. Cigarette tobacco is divided into Oriental and American. In the USSR, oriental cigarette tobacco was most widely used, the varieties of which, according to smoking qualities, are divided into aromatic (flavoring, added to tobacco raw materials in small quantities) and skeletal, which form the basis of smoking products.

Biological features

Temperature requirements

Tobacco seeds begin to germinate at a temperature of 10-12 °C. The optimum temperature is 25-30 °C. At temperatures above 35 °C, tobacco growth stops.

Frosts -2 … -3 °С are detrimental to young plants. However, in autumn, tobacco tolerates short-term low temperatures well.

Moisture requirements

The optimum soil moisture for tobacco is 65-70% from the lowest soil moisture capacity.

The greatest need for water falls on planting and rooting seedlings, as well as during the formation of leaves and intensive plant growth. The lack of moisture at this time leads to a decrease in leaf size and premature ripening, which causes a decrease in yield and quality of tobacco.

Excess moisture, especially on heavy clay soils, leads to wetting of plants.

Transpiration coefficient 500-600.

Soil requirements

Light textured soils with a low humus content are considered optimal for tobacco. An excess of organic matter in the soil leads to a deterioration in the smoking qualities of tobacco.

Tabakh is a chlorophobic culture. Sodium and calcium chloride compounds in the soil reduce its combustibility.

Heavy clay, saline and waterlogged soils are unsuitable for cultivation.

Light requirements

Tobacco belongs to light-loving plants.

The lack of illumination leads to a delay in the development of plants and a decrease in the quality of raw materials.

Vegetation

There are two periods in tobacco culture:

  • growing seedlings from seeds in greenhouses or soil ridges;
  • growing tobacco from seedlings in the field.

The seedling formation period usually lasts 45-50 days, but depends on the variety and usually ends by the time 5-6 true leaves appear.

The period from planting seedlings in the field to the onset of technical ripeness of the leaves of the upper tier lasts 80-120 days. Rooting of seedlings after its transplantation in the field is 10-15 days, after which the phases of stemming, budding, flowering, seed formation and maturation begin.

The formation of leaves in tobacco occurs in tiers.

Technological properties of leaves are determined by varietal characteristics, layering, growing conditions.

Crop rotation

The best forerunners of tobacco in a crop rotation are considered to be winter crops, sugar beets, corn, annual legumes and grasses. On less fertile soils, tobacco is recommended to be placed after leguminous crops and along the reservoir turnover.

With a high saturation of the crop rotation with tobacco, it is allowed to re-plant it in a year, after which it is returned to this field only after 3-4 years. However, the scientifically substantiated inclusion of tobacco in the crop rotation allows increasing its yield by 1.5-2 times compared to permanent and repeated crops.

According to the All-Russian Research Institute of Tobacco and Shag, tobacco is recommended to be placed on light sandy, coarsely skeletal and low-humus podzolized piedmont soils along a layer of perennial grasses; on rich fertile soils – according to the turnover of the layer, in some cases in the third year after perennial grasses.

Tobacco crop rotation

Plantings of tobacco are usually placed near water sources and drying facilities. For this reason, this crop is cultivated in special tobacco crop rotations with a narrow set of crops.

Tobacco crop rotations are tilled, grass-rowed, fruit-shifting. They are built on the placement of tobacco according to the best predecessors for it – winter wheat, perennial grasses, sugar beets, corn, annual legumes and cereal grasses.

Undesirable predecessors are hemp, sunflower, gourds, nightshade crops, as they have pests and diseases in common with tobacco.

In the foothill regions of the Krasnodar Territory, the following tobacco crop rotation is used: 1-2 – alfalfa of the 1st-2nd year of use, 3 – tobacco, 4 – corn, 5 – tobacco, 6 – annual grasses, 7 – tobacco, 8 – spring barley with oversowing perennial herbs. The share of tobacco is 37.5% of the total area.

On poor podzolized soils of the Krasnodar Territory, tobacco is cultivated according to the layer of perennial grasses, as well as in the third year after them in crop rotation: 1-2 – perennial grasses of the 1-2nd year of use, 3 – tobacco, 4 – corn or Sudanese grass, 5 – tobacco, 6 – spring barley with overseeding of perennial grasses. The share of tobacco is 33% of the area.

In a number of farms in the Krasnodar Territory, crop rotation is used: 1-2 – perennial grasses of the 1st-2nd year of use, 3 – winter wheat, 4 – tobacco, 5 – winter wheat, 6 – tobacco, 7 – Sudanese grass, 8 – tobacco.

In the foothill regions of the Kuban, the following 8-field grain-grass row (fruit shift) crop rotation is used: 1-2 – perennial grasses, 3 – winter wheat, 4-5 – tobacco, 6 – winter wheat + intermediate crop, 7 – tobacco, 8 – corn.

In the humid zone of the subtropics of the Krasnodar Territory, the following tobacco crop rotation was introduced: 1 – two-cut clover, 2 – tobacco + intermediate crop, 3 – corn + intermediate crop, 4 – tobacco, 5 – cereals with clover oversowing.

Fertilizer system

Tobacco places high demands on nutrient availability. On average, for the formation of 100 kg of leaves, it absorbs from the soil 6 kg of nitrogen, 1.7 kg of phosphorus, 4.6 kg of potassium and 6.7 kg of calcium. Therefore, this crop responds well to the application of organic and mineral fertilizers.

In turn, nitrogen fertilizers should be used in moderation, since excess nitrogen in the soil degrades the quality of tobacco raw materials. The combined application of nitrogen and phosphorus-potassium fertilizers weakens the negative effect of excess nitrogen.

Since tobacco is a chlorophobic crop, it is not recommended to use chlorine-containing fertilizers.

To obtain 15-20 kg/ha of tobacco leaf yield, it is recommended to apply 10-15 t/ha of manure, 30-60 kg/ha of nitrogen, 80-120 kg/ha of phosphorus, 70-100 kg/ha of potassium (Vavilov; according to others data, from N15-20P50-60K70-75 to N45-60P90-100K120-150, Kolomeichenko). Manure and 2/3 of the entire norm of phosphorus and potash fertilizers are applied in the fall for deep plowing, nitrogen and the rest of the phosphorus and potash fertilizers are applied in the spring during cultivation and for top dressing. When cultivating tobacco under irrigation or excessive moisture, mineral fertilizers are applied in the spring under plowing.

Top dressing is carried out at the beginning of intensive growth of tobacco, that is, 10-12 days after planting seedlings. With weak growth, a second top dressing is carried out 8-10 days after the first.

The lack of boron in the soil can cause the tops of tobacco plants to dry out.

Tobacco responds positively to zinc and lithium fertilizers. For foliar top dressing, a solution containing up to 0.1% lithium is used.

Tillage system

Autumn tillage provides for:

  • double stubble peeling to a depth of 5-7 cm and 10-13 cm;
  • autumn tillage to a depth of 25-30 cm (Vavilov; according to other sources, 20-22 cm, Kolomeychenko), which should be carried out in a timely manner.

Spring tillage includes:

  • fallow harrowing;
  • 2-3 cultivations with simultaneous harrowing.

The number of cultivations depends on the weediness of the fields and the timing of planting seedlings.

Growing seedlings

Tobacco is grown only in seedlings. Seedlings are grown in heated and solar greenhouses (nurseries), in film greenhouses or on soil ridges.

Nurseries should be placed on level ground with a slight slope to the south or southwest. They should be well lit and located away from tobacco fields, dryers and tobacco storage facilities in order to prevent infection of seedlings with grouse, mosaic and other diseases.

Nurseries for tobacco are prepared in the same way as for vegetable crops.

Sowing

The timing of sowing tobacco seeds in nurseries is determined by the timing of planting seedlings in the field. Depending on the type of nursery and weather conditions, it takes 35-65 days to get ready seedlings. For example, in the North Caucasus, seedlings in heated greenhouses are obtained on the 45th day, in sunny – on the 55th, in soil beds – on the 60th day after sowing.

The seeding rate for greenhouses is 0.6 g/m2, warm ridges – 0.8 g/m2, cold ridges – 1 g/m2.

Seedling care

Tobacco seedling care includes:

  • irrigation;
  • ventilation;
  • top dressing;
  • weeding;
  • pest and disease control.

Watering the seedlings is done in small portions of water, but often, preventing the surface of the nutrient mixture from drying out.

The optimum temperature from sowing to germination is 22-28 °C, after germination – 18-25 °C. In greenhouses with technical heating, the temperature is regulated by heating, in greenhouses of another type – by ventilation and covering them with insulation mats.

3-4 times the seedlings are fertilized with mineral and organic fertilizers. The rate of application of mineral fertilizers in top dressing in the form of a solution: nitrogen 2 g/m2, phosphorus 2 g/m2, potassium 5 g/m2. The consumption of the solution is 200 l per 100 m2.

For fertilizing with organic fertilizers, fermented infusion of chicken manure, diluted 1:20 or 1:30, is usually used.

Weed control on seedling crops is carried out as they appear.

Thickened seedlings are thinned out.

Before weeding and thinning, if the nurseries are dry, watering is carried out.

By the time of planting, the seedlings should have a well-developed root system, a flexible, dense stem with 5-6 true leaves.

Seedlings are hardened before sampling. To do this, for 8-10 days it is watered after 1-2 days, stopping it 2-3 days before transplantation.

The output of seedlings is 2500 pcs/m2 on greenhouses with a warming layer, 2000 pcs/m 2 on solar greenhouses, 1500 pcs/m2 on soil ridges. There are 40-60 m 2 of nurseries per hectare of plantings, depending on the variety.

NPO “Tabak” and the Moldavian Research Institute of Tobacco developed a technology for growing seedlings on a nutrient mixture that has not been replaced for 4-5 years. The technology provides for the annual disinfection of greenhouse or greenhouse soil.

Transplanting

Planting seedlings in the field is started when the temperature of the topsoil reaches 10-12 °C and the danger of frost has passed. For most tobacco-growing areas, these conditions fall on the third decade of April. Planting seedlings should be completed before the third decade of May.

Early planting dates are advantageous, especially in the Crimea, where spring is often dry.

The density of standing tobacco plants depends on the area of ​​cultivation and varietal characteristics:

  • small-leaved varieties are planted according to the scheme 50 × 12 cm at a plant density of 150-200 thousand pieces/ha;
  • medium-leaved – 60 × 20-24 cm with a density of 80-90 thousand pieces/ha;
  • large-leaved – 70 × 30 and 90 × 20 cm with a density of 45-55 thousand pieces/ha.

Tobacco planting is carried out by transplanters. For row planting, the МПР-4 transplanter can be used.

Landing care

An important technique for caring for tobacco plantings is considered to be inter-row tillage, which is usually 3-4 with an interval of 8-12 days.

The first treatment is carried out to a depth of 6-8 cm, the subsequent – 10-12 cm. If the soil moisture is insufficient, the treatment is done to a depth of 6-8 cm.

When growing tobacco under irrigation conditions, plantations are watered 2-6 times. Irrigation rate 500-800 m3/ha.

Special methods of planting care are cleaning, topping and pinching tobacco.

Erasure – removal of the lower seedling leaves, followed by their destruction. This technique contributes to a better development of the leaves of the following tiers.

Topping – removal of inflorescences. It is carried out from the beginning of flowering 3-4 times.

Pasynkovanie – removal of side shoots. Carried out simultaneously with topping.

Topping and stepping help to increase the yield, due to the fact that plastic substances are not spent on the further development of inflorescences and side shoots, but are used by the leaves.

Tobacco is considered a medium competitive crop. Parasitic weeds (broomrape (Orobanche) and dodder (Cuscuta)) can appear in tobacco plantations. In the fight against parasitic weeds, crop rotation is of great importance, which should include crops resistant to these weeds: barley, wheat, rice, oats, millet or perennial cereal grasses.

The main pests of tobacco include: slugs, bear, tobacco thrips, wireworm, meadow moth, black weevil. Main diseases: black root rot, bacterial grouse, powdery mildew, mosaic, ring spot, etc.

Harvest

Tobacco leaves ripen unevenly. The oldest lower leaves ripen first, then the middle and last the upper leaves. Most varieties have five tiers of ripening.

Tobacco leaves are harvested by hand. For this, 5-10 breaks are made within 1.5-2 months. The number of breaks, as a rule, coincides with the number of maturation tiers. For one break, 3-7 leaves are removed from one plant.

The harvested leaves are stacked in packs and immediately sent to drying sheds, where they are sorted, strung on cords 5-6 m long and dried.

Drying tobacco

Tobacco drying is carried out in two phases: languor and fixation (drying itself).

Languishing is carried out in drying sheds on special frames – wagons on which cords with strung leaves are hung. The optimal languishing temperature is 25-30 °C, while breathing and evaporation of moisture by plants continues. When languishing in the tissues of the leaf, the breakdown of proteins occurs, the conversion of starch into sugar and the destruction of chlorophyll. The content of nicotine in the leaves decreases, but the amount of aromatic substances increases. Moisture loss during languishing is 6-7%, dry matter – 10-16%. As a result of languishing, the leaves turn yellow, their quality increases. The duration of languor is usually 3-4 days.

After languishing, fixation is carried out, that is, the final drying of tobacco in the sun for 15-20 days or in special fire dryers at a temperature of 40-42 °C at the beginning of drying and 48-50 °C at the end.

For tobacco drying, СТГ-1.5 production lines can be used, which can reduce labor costs by 35-40% compared to pipe-fired drying. The production line СТГ-1.5 for drying tobacco, fixed on cords in vertical garlands, allows the use of a continuous technology of languishing, drying and moistening the leaves.

A relatively newer way of drying large-leaf tobacco – in bulk – is to place the leaves in cassettes equipped with metal needles. For this method, the СТМ-60, УСТП-10, 801-ТУ installations are used.

After drying, the leaves are sorted according to the established standard into five grades, tied into bales and handed over to procurement points. Humidity of commercial raw materials in bales (20-25 kg each) should not exceed 19%. From the procurement points, tobacco is sent to fermentation plants to improve quality and impart resistance to mold, from where it is already delivered to tobacco factories.

Sources

Crop production / P.P. Vavilov, V.V. Gritsenko, V.S. Kuznetsov and others; Ed. P.P. Vavilov. – 5th ed., revised. and additional – M.: Agropromizdat, 1986. – 512 p.: ill. – (Textbook and textbooks for higher educational institutions).

V.V. Kolomeichenko. Crop production / Textbook. — M.: Agrobusinesscenter, 2007. — 600 p. ISBN 978-5-902792-11-6.

Medicinal and alkaloid plants

Medicinal and alkaloid plants include:

  • geranium (Geranium);
  • fenugreek (Trigonella);
  • motherwort heart (Leonurus cardiaca);
  • five-lobed motherwort (Leonurus quinquelobatus);
  • golden root (Rhodiola rosea);
  • yarrow (Achillea millefolium);
  • Jacob’s-ladder (Polemonium caeruleum);
  • coneflowers (Echinacea);
  • clary sage (Salvia sclarea);
  • common sage (Salvia officinalis);
  • elecampane (Inula helenium);
  • common nettle (Urtica dioica);
  • common thyme (Thymus vulgaris);
  • greater celandine (Chelidonium majus);
  • belladonna (Atropa belladonna);
  • fireweed (Epilobium);
  • goat’s rue (Galega officinalis);
  • greater burdock (Arctium lappa);
  • great burnet (Sanguisorba officinalis);
  • tobacco (Nicotiana tabacum);
  • strong tobacco (Nicotiana rustica);
  • peppermint (Mentha piperitя) ;
  • Valerian officinalis (Valeriana officinalis);
  • Tangut rhubarb (Rheum palmatum);
  • chamomile (Matricaria chamomilla);
  • marigold (Calendula);
  • winter rye spores.

In Russia, medicinal plants are cultivated in specialized farms in the south, in the non-chernozem and forest-steppe zones, in some regions of Siberia and the Far East.

In total, more than 50 species of medicinal plants have been introduced into the culture.

Horticulture

Navigation


Horticulture

History

The ancestors of modern man used wild plants for not only nutrition, but also for treatment. After the advent of agriculture, people learned to grow some of them.

The first written evidence of the use of medicinal plants refers to the state of the Sumerians, which existed on the territory of modern Iraq in 6000 BC.

Treatment with the help of plants – phytotherapy – still exists today, despite the widespread use of artificially synthesized pharmaceuticals. Many medicinal plants are collected and harvested in natural phytocenoses (forests, swamps, meadows, steppes, mountains, etc.). However, since the second half of the XX century. more purposeful introduction and selection of the most valuable medicinal plants began.

In the State Register for 2006, several dozen varieties of medicinal plants were included. Thus, at the end of the 20th century, a new group of industrial crops appeared in crop production – medicinal and alkaloid plants.

A clear distinction between medicinal plants and other field crops cannot be called clear. So some essential oil crops (coriander, anise, peppermint, clary sage, etc.) can be included in a separate group of medicinal plants. Often, tobacco and shag are isolated separately.

Alkaloid plants (cocoa, tea, coffee, poppy, etc.) are widely used, which contain various alkaloids (ephedrine, caffeine, quinine, nicotine, etc.) and have a strong physiological effect on the nervous system of humans and animals. Due to the content of alkaloids in these plants, they are widely used in medicine and veterinary medicine.

Despite the fact that tobacco and shag smoking, due to the negative impact on human health, has become catastrophic in our country and throughout the world, the nicotine alkaloid (a strong poison!) Obtained from these plants is used to produce pharmaceuticals and insecticides.

It should be noted that some cereals, legumes, technical and fodder crops, in addition to their main purpose, can also be used as medicinal plants. So, in some textbooks, amaranth is classified as a rare fodder plant, but in the ancient American states (Aztecs and Incas), this culture was used as a medicinal and food crop. Also, leuzea safflower-like (maral root) and Jerusalem artichoke can be simultaneously attributed to fodder and medicinal plants.

Medicinal crop rotations

Medicinal cultures are subject to high requirements for product purity. Therefore, they are cultivated in environmentally friendly conditions. Growing technology eliminates their contamination with residual agrochemicals, therefore, great importance is attached to the use of organic fertilizers, agrotechnical and biological methods of protecting plants from diseases, pests and weeds, and primarily crop rotation.

In most cases, medicinal crops are introduced into regular field, special and sometimes fodder crop rotations. They are placed according to the best predecessors – bare and seeded fallows, layer and turnover of the layer of perennial grasses, legumes, after winter crops, following the best predecessors, row crops.

Perennial medicinal crops can be introduced into hatching fields, where they are cultivated continuously for several years.

Cultivation features

Taking into account the peculiarities of the implementation of many medicinal plants, the Kabardino-Balkarian Agricultural Academy (Fisun M.N.) proposed a technology for the multilateral use of plants that simultaneously have medicinal, fodder, decorative and other properties.

Under production conditions, a comprehensive experiment was carried out, in which single-species tape crops of goat’s rue, high elecampane, woolly comfrey and dioica nettle are used depending on the market situation. If it is possible to sell medicinal raw materials, cleaning is carried out along the tapes. If there is no opportunity to sell medicinal raw materials, the plants are used to harvest high-quality silage or haylage, for which the green mass is mowing across the tapes. Such permanent multi-purpose plantations showed high and stable productivity: 2.5-4 t/ha of medicinal raw materials or 45-60 t/ha of green mass.

Sources

V.V. Kolomeichenko. Crop production / Textbook. — M.: Agrobusinesscenter, 2007. — 600 p. ISBN 978-5-902792-11-6.

Kenaf

Kenaf is a valuable fiber crop.

Economic importance

Kenaf stems contain up to 24% fiber, which is strong, soft and hygroscopic. Tarpaulin, sacking, container, carpet and furniture fabrics, ropes, ropes and other products are made from fiber.

The kenaf fire is used for the production of building boards and paper. The seeds contain 18-20% oil (fat), which is used in the leather, soap and paint industries. The cake goes to feed livestock.

Crop history

The homeland of kenaf is considered to be South America, where it is distributed in the wild.

Cultivation areas and yield

Kenaf is grown in India, China, Indonesia, Burma, Sudan, Brazil.

On the territory of the former USSR, kenaf is cultivated on irrigated lands in Uzbekistan. The area under crops in the 1980s was about 15 thousand hectares (statistics for the USSR).

On green and seed crops, the yield of kenaf stalks can reach 18 t/ra or more. The largest yields of 20-25 t/ha were obtained annually on the Politotdel collective farm of the Communist region, the Akhunbaev collective farm of the Srednechirchik region, the Lenin collective farm of the Galabinsky region of the Tashkent region, etc.

Botanical description

Kenaf (Hibiscus cannabinus L.) is an annual herbaceous plant of the Malvaceae family .

The root is taproot, well developed, penetrating to a depth of more than 2 m.

The stem is round or slightly ribbed, 2 to 5 m high, branched, with anthocyanin coloration. At the base, the thickness of the stem is 1.5-2.0 cm.

The leaves are alternate: the lower ones are simple, the middle ones are lobed, the upper ones are lanceolate with serrated edges.

The flowers are large, up to 7 cm in diameter, five-petalled, yellow, cream, light lilac, pink in color with a dark cherry or pale reddish spot inside the corolla. Plants begin to bloom from the lower flowers. Each flower blooms for one day. Self-pollination prevails, with underdeveloped anthers, cross-pollination can be observed.

The fruit is a five-celled, ovoid-pointed capsule, about 2.5 cm long, 1-2 cm wide, covered with fine bristles. On one plant, 20-30 boxes are formed.

Seeds triangular, dark gray. One box contains 15-20 seeds. Weight of 1000 seeds 20-28 g.

Biological features

Temperature requirements

Kenaf is a thermophilic plant.

Seeds begin to germinate at a temperature of 10-12 °C. The optimum temperature for the appearance of uniform seedlings is 20-22 °C.

Frosts -1.0 … -1.5 °C lead to the death of seedlings and adult plants.

The optimal temperature for the growth and development of kenaf is 23-25 ​​°C. By the end of the growing season, heat requirements are noticeably reduced.

Moisture requirements

For kenaf, the optimum soil moisture is 80% from the lowest soil moisture capacity. Therefore, kenaf can be cultivated either in irrigated conditions or in regions rich in rainfall.

The greatest need of plants for water falls on the period of rapid growth, that is, when a three-blade leaf appears.

Soil requirements

Typically, kenaf is sown on alluvial soils of river valleys, gray soils, meadow and meadow-marsh soils.

Salt and waterlogged soils are not suitable for cultivation.

Light requirements

Kenaf is a photophilous plant of a short day.

The lack of lighting, which can be observed on heavily thickened crops, leads to short stature and weakening of plants.

Vegetation

The vegetation period of kenaf is 120-160 days.

Crop rotation

In crop rotation, the predecessors of kenaf can be winter cereals, tilled crops, legumes and alfalfa.

Fertilizer system

Kenaf is a rather demanding culture in terms of nutrition. With a stem yield of 10 t/ha, kenaf removes 120-150 kg of nitrogen from the soil, 60-80 kg of phosphorus and 120-160 kg of potassium.

At the beginning of the growing season, the greatest need is noted for phosphorus and potassium. Nitrogen consumption increases significantly during the budding and flowering phases.

Kenaf is responsive to fertilization. A particularly good result is obtained from the joint application of manure (15-20 t/ha) and mineral fertilizers.

The approximate recommended application rate of mineral fertilizers to obtain 18-20 t / ha of stems is: nitrogen – 220-250 kg, phosphorus – 150-170 kg and potassium K – 90-100 kg/ha. When placing kenaf after alfalfa, the fertilizer rates in the first year are somewhat reduced.

Manure and half of the total norm of phosphorus and potash fertilizers are applied for autumn tillage, 25-30 kg/ha of nitrogen and phosphorus – at sowing, the rest of the fertilizer – for top dressing. Top dressing of crops of kenaf is carried out in the phase of 8-10 leaves and in the phase of the beginning of budding.

Tillage system

Tillage for kenaf includes:

  • peeling;
  • autumn plowing with plows with skimmers to a depth of 28-30 cm in September;
  • early spring plowing;
  • 1-2 cultivations with simultaneous harrowing.

Before sowing, the field is planned and harrowed.

Sowing

Seed preparation

Before sowing, conditioned seeds are subjected to air-heat treatment in open areas. Seeds are treated with 80% TMTD at the rate of 200 g/100 kg of seeds.

Sowing dates

Sowing of kenaf is started when the soil warms up to 12-15 °C.

For Uzbekistan, the optimal sowing time for greens is April 10-20, when grown for seeds – April 1-10.

Seeding methods

The most progressive method of sowing when growing greens is a two-row belt with a width between the ribbons of 70 cm and a distance between the lines of 20 cm. The seed sowing rate by this method is 25-30 kg/ha.

With the seed crop of kenaf, a wide-row sowing method with row spacing of 60 cm is usually used. The sowing rate in this case is 8-10 kg/ha.

Seeding depth

Sowing depth on light soils is 5-6 cm, on heavy soils – 3-4 cm.

Crop care

Kenaf plants at the beginning of the growing season develop slowly, so the greatest care is required for crops during this period. The destruction of the soil crust at this time is carried out with the help of light harrows.

During the growing season, the number of inter-row treatments reaches 5-6. They are carried out immediately after watering, as soon as it becomes possible due to the state of soil moisture. Usually, inter-row cultivation continues until the rows close.

During the growing season, 5-6 waterings are carried out on green crops: the first watering is carried out at a plant height of 12-15 cm, the next – after 15-20 days. The irrigation rate is 1000-1200 m3/ha.

On seed crops, after the first cultivation, thinning is done, after which the plant density should be 150-180 thousand plants per 1 ha. Three waterings are usually carried out: the first – in the phase of 18-20 leaves, the second – in the budding phase, the third – in the flowering phase. Irrigation rate – 3500-4000 m3/ha.

Harvest

The harvesting of kenaf for greenery is started at the onset of technical ripeness, that is, when at least 50% of the plants bloom. To obtain bast, freshly cut stems are processed using a ЛО-1А bast separator. The resulting green bast is dried, for which it is spread over the stubble in an even layer. After drying, the bast is collected in bales weighing 10-12 kg. Before delivery to the procurement points, the bast is sorted.

Kenaf harvesting can be carried out using kenaf harvesters, for example, КУ-0.2, which cuts the stems, separates the undergrowth and weeds, processes the stems into bast and lays them on the ground to dry.

Harvesters ЖК-2.1 are used for harvesting kenaf for seeds. Harvesting is started when 3-4 lower bolls are browned in 75% of plants. In the conditions of the Tashkent region, which is the only producer of kenaf seeds for all regions of Uzbekistan, harvesting is usually carried out on September 5-16.

Cut stems are dried, for which they are left on the field for 3-4 days. Then the stems are tied into sheaves and set in small musts to dry. Dried sheaves are subjected to threshing, for which mobile threshers МКФ-6 are used. Seeds are sorted, and the remaining stems are tied into sheaves and sent for delivery to bast plants.

Sources

Crop production / P.P. Vavilov, V.V. Gritsenko, V.S. Kuznetsov and others; Ed. P.P. Vavilov. – 5th ed., revised. and additional – M.: Agropromizdat, 1986. – 512 p.: ill. – (Textbook and textbooks for higher educational institutions).

Fiber flax

Fiber flax is an agricultural fiber crop.

Economic importance

The flax stem contains 20-30% of bast, in highly productive varieties and more. Linen fiber is characterized by high technological properties: strength, flexibility, thinness, etc. It is 2 times stronger than cotton fiber, three times woolen and second only to silk.

Linen fiber is used for the production of household, technical, container and packaging fabrics. From 1 kg of fiber, 10 m2 of batiste or 2.4 m 2 of linen, 1.6 m2 of technical fabrics or 1 m2 of tarpaulin are produced. Linen fabrics are wear-resistant and resist decay. They are in demand all over the world.

In the production of fabrics, flax fiber is considered one of the best components when used together with chemical fibers.

Flax seeds contain 35-42% by weight of seeds of a well-drying oil, which is used in the production of paints, varnishes, drying oils, in soap making, paper, electrical and other industries, as well as in medicine and perfumery. A small part of linseed oil is used for food purposes.

Flaxseed cake serves as a good concentrated feed for livestock. 1 kg corresponds to 1.15 feed units. It contains 6-12% fat and up to 30 (36)% digestible protein.

When processing trusts into fiber, short spun fiber (tow) is obtained, which is used for the manufacture of sack and packaging fabrics, as well as non-spun fiber (tow), which is used to make ropes, twine and as caulking material. Bonfire (stem wood) serves as a raw material in the production of cardboard, ethyl alcohol, acetic acid, acetone and other materials, is used for the production of building boards (fireplates) and insulating materials.

The wood of the stems can serve as organic fertilizer and be used as fuel.

Flax has medicinal value.

The share of flax straw in the yield of fiber flax is 70-75%, and with high yields – about 80%. The share of seeds is 10-15% (in seed crops up to 30%) and the share of chaff is 10-15% of chaff. The output of the trust from the harvest of flax straw averages 70%.

Crop history

Flax is one of the oldest crops of agriculture. It was known in India, China, Egypt, Mesopotamia and Transcaucasia for 4-5 thousand years BC. It is assumed that the birthplace of this culture is Southwest and East Asia, as well as the Mediterranean.

On the territory of Russia, it was grown in ancient times. Back in the XII century. flax was grown in the Novgorod and Pskov principalities. Linen was used to make fabrics and other products that were used not only to meet their needs, but also for exchange. In the XV century. the volume of export of fiber and flax seeds to other countries has reached the largest size. In the XVI century. The first rope factory was built in Russia. In 1711, Peter 1 issued a decree on the expansion of flax sowing, and a little later, a decree appeared on the norms of flax sowing. At the same time, state-owned linen factories were built, producing wide linen sheets for sails and other needs. Until the end of the XVIII century. flax fiber occupied the first place among Russian goods intended for export.

Pskov, Novgorod, Kashin, Kostroma flax were especially known on the world market. At the beginning of the XX century. The Russian Empire was the main supplier of flax fiber.

Prior to the widespread introduction of sunflower in the Russian Empire, oilseed flax served as the most important source of vegetable fat and fodder cake.

Cultivation areas and yield

The area under fiber flax crops in the world in the mid-1980s was 1.5 million hectares, while more than 70% of the world area (1.06-1.1 million hectares) was concentrated in the USSR.

Significant areas of crops are available in the Netherlands, Belgium, France, England, Germany, the Czech Republic, Slovakia, Poland, Romania, and on limited areas also in Canada, the USA and Japan.

The area under oil flax crops in the world was 1.06 million hectares. The share of the USSR accounted for 10% (90 thousand hectares) of the world’s area. Large arrays of it were in Argentina, USA, Canada, India.

Fiber flax is grown in Russia in regions of a humid and temperate climate, oilseed flax – in drier and warmer regions. The main crops of fiber flax are located in the Non-Chernozem zone (Tver, Smolensk, Yaroslavl, Vologda, Pskov, Kostroma and other regions), as well as in Belarus, Ukraine, and the Baltic countries.

In the early 2000s the area occupied by fiber flax in Russia is 120 thousand hectares. During the period from 1970 to 2000, the area under crops was sharply reduced: in 1970, 727 thousand hectares were occupied; 1980 – 595 thousand hectares; 1990 – 418 thousand hectares; 2000 – 108 thousand hectares. The gross harvest of flax fiber also dropped sharply: from 207 thousand tons in 1971-1975. up to 52 thousand tons by the beginning of the 2000s.

Oil flax crops in Russia are located in the Central Black Earth zone, the Volga region, Western Siberia, as well as in Kazakhstan, in the steppe part of Ukraine, in Tajikistan, Uzbekistan, Kyrgyzstan and Armenia.

The yield of flax fiber in 1976-1980 in the USSR, the average was 3.4 c/ha, in 1984 – 3.8 c/ha. In terms of the gross harvest of flax fiber, the USSR ranked first in the world. The maximum yield was obtained in the Pochinkovsky district of the Smolensk region (1983) on an area of ​​9 thousand hectares and amounted to 7 centners per hectare of fiber and 4 centners per hectare of seeds.

Botanical description

The genus Linum of the Flax family (Linaceae) includes more than 200 species that are distributed in temperate and subtropical regions of all parts of the world. These are predominantly annual, sometimes perennial herbaceous plants.

On the territory of Russia and the countries of the former USSR, 40-45 types of flax are found. Among them, flax is of agricultural importance – Linum usitatissimum L.

According to the modern classification, common flax is divided into five subspecies, of which only 3 are of greatest importance in Russia:

  • Mediterranean subspecies – subsp. mediterraneum Vav. et El . Plants are undersized (up to 50 cm). Flowers, bolls and seeds are large. Weight of 1000 seeds 10-13 g. Cultivated in the Mediterranean countries.
  • Intermediate subspecies subsp. transitorium ell . Plants of medium height (50-60 cm). Flowers, bolls and seeds of medium size. Weight of 1000 seeds 6-9 g. Distributed as an oilseed crop in the south of Ukraine, in the Crimea, Transcaucasia and Kazakhstan.
  • Eurasian subspecies – subsp. eurasiaticum Vav. et El . Plants varying in height and branching. Flowers, bolls and seeds are small. The weight of 1000 seeds is 3-5 g. The most common subspecies in the culture. Cultivated in Europe and Asia.

The Eurasian subspecies is also subdivided into 4 groups of varieties:

  1. Fiber flax (elongata). Tall (from 60 to 120 (175) cm) single stem plants, branching only in the upper part. Stems are light green or bluish green. Leaves lanceolate, sessile. The flowers are regular, quintuple type, with blue, pink or white petals. Five stamens with blue, orange or yellow anthers. Pistil with five-celled ovary and five styles. The fruit is a five-celled capsule, divided by partitions into ten half-nests. One seed develops in each semi-nest. Seeds are flat, ovoid, brown or brown. On one plant, depending on the density of crops, from 2-3 to 8-10 seed pods are formed. The root system of fiber flax is underdeveloped, it consists of the main tap root and small tender branches located in the upper soil layer, mainly in the arable layer.
    Fiber flax is cultivated in areas of moderately warm and humid climate.
  2. Curly flax, or stag (v. brevimulticaulia). A low-growing (30-50 cm) plant with a strongly branching stem at the base and a large number of bolls (from 30-35 to 50-60 or more). Seeds are larger than those of the longweed. The weight of 1000 seeds is about 8 g. It is cultivated for oil production in the countries of Central Asia and Transcaucasia.
  3. Intermediate flax, or intermediate flax (v. intermedia). Plants of medium height (50-70 cm), 1-2 stems. Usually there are more bolls than those of the long-tailed bat (10-25). More often cultivated for oil, less often for oil and fiber, in the Central Black Earth zone (Kursk, Voronezh regions), in the Volga region (Samara region, Bashkortostan and Tatarstan), partly in Siberia, Ukraine, the North Caucasus, and Kazakhstan.
  4. Creeping flax (v. prostrata). Plants with numerous creeping stems before flowering. By the beginning of flowering, the stems rise and reach a height of 100 cm or more. It is cultivated as a winter crop in limited areas in Transcaucasia.

Forms of flax determine directions in cultivation: two-sided – for obtaining fiber and seeds (dolguntsy) and seed (curly). Mezheumki occupy an intermediate position, usually approaching curls. In Russia, over 85% of all flax crops fall on fiber flax, or spinning flax.

Technological properties of flax fiber

In the stems of fiber flax, 20-30% is accounted for by the fiber, which consists of fiber (88-90%), pectin (6-7%) and waxy (3%) substances, ash (1-2%). The proportion of fiber in the lower part of the stem is only 12%, and its quality is low (thick, rough, partially lignified). In the middle part of the stem, the proportion of fiber reaches 35% and is of higher quality (thin, strong and long, with the smallest cavities inside and thick walls). In the upper part of the stem, the amount of fiber decreases to 28-30%, the quality is somewhat worse (the fibers have a larger clearance and thinner walls).

Bast fibers are located in the parenchymal tissue of the stem cortex in the form of fibrous or bast bundles, which consist of many individual cells called elementary fibers.

Elementary fibrils are elongated cells with pointed ends 15–40 mm long and 20–30 µm thick on average. The fibers are firmly glued together with pectin into a fibrous bundle. Each bundle can contain 25-40 fibers. Fibrous bundles are arranged in a ring of 25-30 bundles along the periphery of the stem. The bundles, connecting with each other, form a tape of technical fiber.

The length of the bast bundles is determined by the total length of the stem and its technical length, that is, the length from the trace of cotyledon leaves to the beginning of branching (the first branch of the inflorescence). Tall stems are more than 70 cm long, have a greater technical length, contain longer elementary fibers and a longer technical fiber. Thin stems (1-1.5 mm) give a higher quality fiber, since their elementary fibers have thick walls and a relatively small internal cavity, which makes it possible to obtain strong and flexible fibers.

The quality of flax fiber is characterized by technological properties: strength, flexibility, fineness, gloss, elasticity, softness, cleanliness, quality factor and spinning ability. The overall fiber quality rating is determined by comparing the fiber with standard references. The higher the number of flax fiber, the less it is spent on the production of 1 m of fabric. High quality fiber should be long, thin-layered, without a large cavity, smooth and clean.

Biological features

Temperature requirements

Moderate temperatures in spring and summer with intermittent rain and clear weather are favorable for fiber flax. In the conditions of Russia, such conditions are most often observed in the forest zone. Its seeds begin to germinate at a temperature of (2) 3-5 °C. Seedlings are able to withstand frosts down to (-3) -4 (-5) °С. However, at this temperature, damage to the cotyledons and yellowing of the seedling are observed.

Active germination of seeds and the emergence of seedlings are observed when the soil warms up at a depth of sowing seeds to 7-9 °C. The sum of effective temperatures for the period from sowing to germination is -60 °C, from germination to the beginning of flowering – 418-440 °C, from flowering to browning of the bolls – 410 °C (Schegolev). For the entire development cycle of flax, the sum of active temperatures is required from 1000 to 1300 °C.

The optimal temperature for plant growth is (15) 16-17 (18) °C. Hot weather leads to a delay in the growth of stems in height. At a temperature of 22 °C, growth inhibition is already noted, especially with insufficient moisture supply to the plants. Sharp diurnal temperature fluctuations also have a negative effect, especially during active growth (the budding phase).

Oil flax (mezheumok and especially curly) makes higher demands on heat than fiber flax, especially in the ripening phase. They are also more resistant to high temperatures and drought. For curly flax, warm sunny weather with a relatively dry summer (forest-steppe and steppe) is optimal.

Moisture requirements

Fiber flax makes very high demands on moisture. The maximum demand falls on the periods of budding and flowering.

The optimal soil moisture is 70% of lowest soil moisture capacity. At the same time, fiber flax needs moisture in different phases of development.

For swelling of seeds, about 100 (180)% of water is required from their mass. Friendly seedlings appear at an optimum soil moisture content of 10-20 mm in a 10 cm layer. Starting from the fir-tree phase to flowering, fiber flax’s need for moisture increases, while normal plant growth is possible with productive moisture reserves of 30 mm or more in a layer of 0-20 cm.

Flax does not tolerate excess moisture in the soil, as well as areas with a close occurrence of groundwater. Precipitation during maturation is also unfavorable, as this leads to lodging of plants and the development of diseases. During ripening, dry, moderately warm and sunny weather is considered favorable.

The transpiration coefficient of flax is 400-430 (450).

Oilseed flax (curly and mezheumok) is less demanding on moisture.

Soil requirements

More K.A. Timiryazev noted that on fertile soils, flax gives a thinner and more elastic fiber.

Due to the weak assimilation ability of the root system and a short period of intensive growth of stems, fiber flax is demanding on soil fertility.

In the Nonchernozem zone of Russia, well-cultivated, aerated, medium loamy soils and loamy sandy loams with a low degree of podzolization are considered the best. Optimal slightly acidic soil reaction (pH 5.9-6.3 (6.5)).

In fiber flax, up to 80% of the roots are located in the 0-20 cm layer, 14-18% – in the 21-50 cm layer, 3-6% – in the 51-100 cm layer. Therefore, more than 80% of the crop is formed due to moisture and nutrients of the soil horizon 0-20 cm.

Soils with a humus content of at least 2%, easily hydrolysable nitrogen – 10 mg/100 g of soil, potassium and phosphorus 10-15 mg/100 g of soil, and a bulk density of 1.3 g/cm3 are optimal. However, on very rich soils, plants often lie down, on the contrary, on very poor soils they are stunted. Flax can be grown on poor podzolic soils, but in order to obtain stable good yields of high quality (0.6-0.8 t/ha of fiber and 0.4-0.5 t/ha of seeds), it is necessary to choose good predecessors and follow fertilizer systems and plant protection.

Sandy loams and sands are unsuitable for growing fiber flax. Also, it does not work well on heavy clay, cold, swimming and acidic peaty soils. On limed soils, flax produces a brittle and coarse fibre. Does not tolerate weedy soils.

For oil flax, weed-free chernozems and chestnut soils are optimal. Mezheumok and curly are considered less demanding on fertility. Alkaline, as well as heavy clayey and marshy soils, are of little use for their cultivation.

Light requirements

Long-day flax is a long-day plant. In strong sunlight, increased branching of the stem occurs, which leads to a decrease in the yield of long fiber and a deterioration in its quality.

The most favorable diffused light.

Vegetation

Flax is characterized by the following phases of development:

  • seedlings;
  • the beginning of stalking (“herringbone”);
  • budding;
  • bloom;
  • ripening (sometimes subdivided into fruit formation, seed ripening, full ripeness).

Under favorable conditions, flax seedlings usually appear 5-6 days after sowing.

In the seedling phase, the flax plant has two cotyledon leaves with a small bud between them. In the herringbone phase, the plant reaches a height of 10 cm, while 5-7 pairs of true leaves are formed on the stem. These two phases (approximately 1 month after germination) are characterized by slow growth of the stem in height, but the rapid development of the root system.

Further, flax begins a period of intensive growth of plants in height (gains of 3-5 cm per day). This period lasts 12-20 days and ends with the onset of budding, at the onset of which plant growth slows down to 0.5-1 cm per day, and by the end of flowering almost stops. All agricultural practices aimed at inhibiting this process lead to stem lengthening and fiber quality improvement.

During maturation, the stems of plants are rapidly lignified and seeds are formed in boxes.

According to the Department of Crop Production of the Moscow Agricultural Academy, for the Svetoch variety, the period from sowing to germination is 6-7 days. The fir-tree phase occurs 26-28 days after sowing, budding – after 54-56 days, flowering – after 60-62 days. The growing season lasts an average of 82-84 days. For various varieties, the growing season ranges from 70 to 100 days.

Crop rotation

When using high and intensive agricultural technologies for the cultivation of fiber flax, the predecessors can be winter cereals, legumes, potatoes, corn, sugar beets, a layer or turnover of a layer of perennial grasses.

In Western Europe (Belgium, the Netherlands, etc.), clover is considered a poor predecessor of flax, because due to an excess of nitrogen, it lodges, and the straw turns out to be coarse and branching.

The frequent return of flax to its original place in the crop rotation leads to the accumulation of harmful microorganisms and specific weeds in the soil, which affects the yield. This phenomenon is called “flax fatigue”. They return it to its original place after 7-8 years.

Of great agrotechnical importance are intermediate crops of crops of the Cabbage family (rapeseed, Barbarea, oil radish, etc.), which are used as green manure or for green fodder. These crops are sown after harvesting early cereals.

Fiber flax is considered a good predecessor for winter and spring crops, buckwheat, beets and potatoes.

Falls, a layer of perennial grasses, winter grains, corn, legumes, melons and other row crops are considered good predecessors of oil flax.

Fertilizer system

Flax makes high demands on soil fertility. So, according to numerous data from VNIIL and other experimental institutions, when a complete mineral fertilizer is applied, the yield of fiber flax straw increases by 0.4-0.8 t/ha or 40%, seeds – up to 30%. In addition, the quality of flax fiber is improved.

Flax uses the nutrients of mineral fertilizers in different ways: easily hydrolysable nitrogen is absorbed by about 30-90%, phosphorus – by 10-25%, potassium – by 26-40%; from the soil, respectively: nitrogen – 20-30%, phosphorus – 6-13%, potassium – 12-13%. In conditions of a sufficient amount of moisture in the soil, it is recommended to take the upper gradation.

Nitrogen increases the content of long fiber in the crop. However, its excess lengthens the growing season of plants, leads to lodging of crops and increases the susceptibility to diseases, which ultimately significantly reduces the yield and quality of the fiber. Flax plants are especially sensitive to a lack of nitrogen in the herringbone phase, and the greatest need falls on the period of the herringbone – budding.

Phosphorus is very important from germination to the herringbone phase (5-6 pairs of true leaves). Sufficient phosphorus nutrition accelerates maturation, increases seed and fiber yield. When choosing forms of phosphate fertilizers, it is necessary to take into account their effect on increasing the acidity of the soil, to which flax is very sensitive.

Potassium contributes to an increase in the number of elementary fibers in the stem, increases the yield and quality of flax fiber, reduces the risk of plant lodging, and alleviates the negative effects of excess nitrogen fertilizers. The greatest need for potassium falls on the first 3 weeks of plant growth and in the budding phase.

The removal of nutrients from 1 ton of straw and seeds averages 10-14 kg of nitrogen, 4.5-7.5 kg of phosphorus, 11-17.5 kg of potassium.

On soddy-podzolic soils, the increase in straw yield is 5-7 kg per 1 kg of a.i. fertilizers.

When developing a flax fertilization system, it is necessary to take into account the weak ability of the root system to absorb nutrients from the soil and high sensitivity to high concentrations of soil solution, as well as a short growing season.

The introduction of 30-40 t/ha of manure under previous winter or tilled crops, together with phosphorite flour (400-600 kg/ha) and potassium chloride (150-200 kg/ha), contributes to an increase in yield by 25-30%. Lupins, seradella, vetch and rapeseed, which are grown in stubble crops, can be used as green manure. Manure and composts are not applied directly under flax, as this leads to lodging of crops.

According to the recommendations of All-Russian Research Institute of Flax, 30 kg of nitrogen (or 100 kg/ha of ammonium nitrate) are applied under flax, coming after spring cereals (barley, oats, spring wheat), with their planned grain yield of up to 2.5 t/ha. After cereals with a planned yield of 2.5 to 3.5 t/ha, it is recommended to apply 20-25 kg of nitrogen (or 60-70 kg of ammonium nitrate). With a planned grain yield of more than 3.5 t/ha – 15-17 kg of nitrogen (or 50 kg/ha of ammonium nitrate).

When placing flax after clover, with a hay yield of 3.04.0 t/ha under flax, it is recommended to apply no more than 15-17 kg of nitrogen, and with a hay yield of 4.5-5.0 t/ha, nitrogen under flax is not recommended. The application rate of nitrogen on drained peatlands is reduced, while that of phosphorus and potassium is increased.

The recommended ratio of nutrients in a complete mineral fertilizer for flax is NRK – 1:2:3 on soils poor in nitrogen, and 1:3:4 on soils rich in nitrogen, on poorly cultivated soils – 1:2:2, on medium cultivated soils – 1:3:3, on highly cultivated – 1:4-6:4-6.

In addition to ammonium nitrate, urea, ammonium sulfate or complex fertilizers – nitrophoska, nitroammophoska and ammophos can be applied under flax. 100 kg of nitrophoska correspond to N12-15Р12-15K12-15, nitroammophoska – N16P16K16 (NPK ratio 1:1:1), ammophos – N11-12Р36-52. The application rate of complex fertilizers per 1 ha is determined by nitrogen, and superphosphate and potassium chloride are added to the missing amounts of phosphorus and potassium.

Under flax, in addition to simple superphosphate, double superphosphate (P34-45) and boron superphosphate containing 19-20% phosphorus and 0.2-0.3% boron can be used.

For the rational use of All-Russian Research Institute of Flax mineral fertilizers, it is recommended to apply nitrogen, phosphorus and potassium under flax, taking into account their content in the soil and the planned yield of flax products (table). At the same time, the recommended fertilizer application rates must be adjusted taking into account zonal characteristics.

Table. Approximate norms for applying mineral fertilizers for flax (data from VNIIL, 1984)[1]Crop production / P.P. Vavilov, V.V. Gritsenko, V.S. Kuznetsov and others; Ed. P.P. Vavilov. – 5th ed., revised. and additional - M.: Agropromizdat, 1986. - 512 p.: ill. - (Textbook and textbooks … Continue reading

THE CONTENT OF NUTRIENTS, MG PER 100 G OF SOIL
PROVISION OF FLAX WITH MOBILE PHOSPHORUS, NITROGEN, EXCHANGEABLE POTASSIUM
PLANNED YIELD OF FLAX FIBER 0.5-0.7 T/HA, SEEDS 400-500 KG/HA
PLANNED YIELD OF FLAX FIBER 0.8-1.0 T/HA, SEEDS 600-700 KG/HA
mobile phosphorus (P2O5)
exchangeable potassium (K2O)
N
P2O5
K2O
N
P2O5
K2O
3
5
Very low
30
90
120
Not planned
Not planned
Not planned
3-9
5-10
Low
25
80
100
Not planned
Not planned
Not planned
10-15
11-15
Medium
20
70
90
20
90
120
16-20
16-20
Increased
15
60
60
15
90
90
21-30
21-30
High
10
45
45
10
60
60
30
30
Very high
0
30
30
0
45
45

On strongly acidic soils with a pH of less than 5.0, it is better to replace superphosphate with a mixture consisting of three parts of phosphate rock and one part of superphosphate, and on medium acid soils (pH 5.5) – a mixture of equal parts of phosphate rock and superphosphate.

Part of the entire rate of phosphate fertilizers is applied when sowing in rows in the form of granulated superphosphate at the rate of 50 kg/ha for commercial crops and 20 kg/ha for seed crops.

From potash fertilizers for flax, potassium chloride (56-60% K2O), potassium sulfate (48% K2O), potassium salt (30-40% K) can be applied. On sandy soils with magnesium deficiency, it is advisable to apply potassium magnesia (K2O 28-30% and MgO 8-10%).

To correct the developed zonal average fertilizer application rates for flax, All-Russian Institute of Fertilizers and Agrosoil Science is recommended to use correction factors taking into account the planned yield and nutrient content in the soil.

Nitrogen fertilizers for flax are applied in the spring, potash and phosphorus fertilizers – in the fall, before the autumn tillage or immediately after it. On soils with a low content of mobile forms of phosphorus and potassium, as well as on heavy cohesive soils, phosphorus-potassium fertilizers are recommended to be applied in two steps: half in autumn, before autumn tillage, and the second half in early spring, before spring tillage.

The main mineral fertilizer is applied randomly using special fertilizer seeders with ПТХ-4.2А plate-type sowing machines. Granular superphosphate is applied when sowing in rows with combined seeders СЗЛ-3.6.

A good effect is given by fertilizing during the growing season of plants. Ammonium nitrate or ammonium sulfate can be used for top dressing. The consumption rate is N20-30, superphosphate – P30-40, potassium chloride – K30 or complex fertilizers. Top dressing begins to be carried out at a plant height of 6-8 cm or 20 days after germination. A delay in nitrogen fertilization can lead to stretching of flowering time and uneven ripening. Often top dressing is done only with phosphate fertilizers.

Of the microfertilizers, flax needs boron the most. Boron-datolite or boron-magnesium fertilizer is applied in the spring before cultivation at the rate of 20-30 kg/ha (Vavilov; according to other recommendations, 40-70 kg/ha of boron, Kolomeichenko). In addition to these fertilizers, with a lack of boron in the soil, boron superphosphate can be used in rows when sown in an amount of 50 kg/ha. Boron reduces the negative effect of lime on flax plants, reduces damage to plants by bacterial diseases. Boric fertilizers are recommended to be applied on calcareous, podzolic and waterlogged soils, as well as in the development of new lands.

Copper microfertilizers should be used when growing flax on peatlands at the rate of 25 kg/ha of copper sulfate or 250-500 kg/ha of pyrite cinders.

Soddy-podzolic soils of the flax growing zone, characterized by high acidity, are subjected to liming . The experiments of All-Russian Research Institute of Flax showed that with the direct application of lime under flax in small quantities, the yield of flax fiber increases, but its quality deteriorates noticeably. The joint introduction of lime and boron somewhat eliminated the negative effect of lime. For this reason, liming of acidic soils in flax crop rotations is carried out under a cover crop of red clover or in a fallow field. The following lime application rates are recommended for:

  • pH 4.5 and below – 2.5-3 t/ha;
  • pH 4.6-5.0 – 2-2.5 t/ha;
  • pH 5.0-5.5 – 2 t/ra.

Lime is applied using mineral fertilizer spreaders 1РМГ-4, РУМ-8. Errors in the application of mineral fertilizers are not allowed, deviations from the specified application rate should be no more than 10%.

A good effect is given by the addition of mineral fertilizers to the addition of wood ash under flax from 100 kg of ash for every 100 kg of fiber.

Manure or peat-dung compost is usually not applied directly under flax, as this can lead to lodging of plants, variegation and weediness of crops. However, under the conditions of intensification of flax growing, the role of organic fertilizers in flax crop rotation increases. According to studies, it is optimal to apply manure and composts in flax crop rotation in two fields – under potatoes or other tilled crops and under winter or spring crops with oversowing of perennial grasses. At the same time, mineral fertilizers should be applied under crops annually.

According to All-Russian Research Institute of Flax, in order to ensure high yields of all crops included in the flax crop rotation, it is necessary to annually apply at least 10-13 t/ha of organic fertilizers and 1 t/ha of standard mineral fertilizers on cultivated soddy-podzolic soil.

The introduction of organic (20 t/ha manure) and mineral (N30P45K40) fertilizers for oilseed flax significantly increases the yield. In this case, phosphorus-potassium fertilizers are applied under autumn plowing, and nitrogen fertilizers are applied under pre-sowing cultivation. When sowing, it is also recommended to add superphosphate or nitrophoska to the rows at the rate of P15-20, which increases the yield of oilseeds by 0.3 t/ha.

Tillage system

Basic tillage

Due to the underdeveloped root system and the small depth of its penetration into the soil, flax is sensitive to tillage, which largely depends on the predecessor. For varieties of flax (fiber, mezheumok, curly), the tillage system, as a rule, does not differ.

When placing flax after perennial grasses, soil cultivation begins with disking the layer in two directions using heavy disc harrows БДН-3, БДТ-10, БДТ-3.0. Disking is performed 2-3 weeks before autumn processing. Plowing is carried out with plows with skimmers to a depth of 22-25 cm, and in the case of a shallow arable layer – to its entire depth.

The optimal plowing time for the central and western regions of the Non-Chernozem zone of Russia is the end of August – the first half of September, in Western Siberia – August, Belarus – September, the Baltic countries – the end of September – the first half of October, in Ukraine – September. At the same time, good tillage in early spring should be ensured.

When placing flax after grain crops, after their harvesting, the soil is peeled to a depth of 4-6 cm with disk cultivators ЛДГ-5А, ЛДГ-10А, ЛДГ-15А or plowshares ППЛ-5-25, ППЛ-10-25. When infested with couch grass (Elytrigia repens), the depth of peeling should be at least 10-12 cm. The crumbled seeds and knots of couch grass rhizomes quickly germinate and, during subsequent autumn plowing, are deeply embedded in the soil and die. With a strong clogging of wheatgrass, it is advisable to use soil-acting herbicides.

When flax is placed after potatoes, if plowing was carried out after its harvesting, additional plowing is usually not carried out.

On weedy crop rotation landsthey often leave a repair fallow field or carry out autumn tillage according to the semi-fallow type. With semi-fallow tillage, plowing and several cultivations are carried out in autumn to control weeds. Peeling is carried out immediately after harvesting the predecessor to provoke the germination of weeds, which are then plowed. If the fields are clogged with annual weeds, a cultivator of the ЛДГ-10 type is used to a depth of 6-8 cm, when clogged with root weeds, ППЛ-10-25 plow-ploughs are used, with a large distribution of creeping wheatgrass, heavy disc harrows БДТ-3.0 or БДТ- 7.0 in two tracks. In dry autumn weather, it is advisable to aggregate the plow with a ring-spur roller, and in wet weather – with a heavy harrow. Before the start of frost, it is desirable to perform 2-3 cultivations to a depth of 10-14 cm diagonally to the direction of plowing. For cultivation, КПС-4 cultivators with spring paws in combination with harrows are usually used. They try to perform the last cultivation 2 weeks before the onset of frost to a depth of 8-10 cm; at the same time, the same cultivators with lancet paws and without harrows are used.

Pre-sowing tillage

In spring, plowing on sandy and light loamy soils is harrowed, on heavy loamy and moist soils it is cultivated. Pre-sowing treatment of sandy loamy soils is carried out with heavy tooth harrows, light and medium loams – needle-shaped (БИГ-3А) and spring (БП-8), heavy loams and clay soils – cultivators to a depth of 5-7 cm.

Early spring processing of loamy and clayey soils, in case of placing flax after grain crops, is carried out by cultivators with lancet paws to a depth of 5-6 cm with simultaneous harrowing with heavy or medium tooth harrows. When incorporating mineral fertilizers, the cultivation depth on these soils is increased to 10-12 cm.

Early spring processing after a layer of perennial grasses raised in the fall (provided there is no couch grass), in order not to turn the turf to the surface, use disc cultivators ЛДГ-10, ЛДГ-5 or disc harrows БД-10, БДН-3.0 (Vavilov; according to others data, they are treated with cultivators with lancet paws, Kolomeichenko).

Presowing tillage, which is reduced to cultivation with simultaneous harrowing, is carried out one week after early spring tillage. Such treatment promotes more complete germination of weeds , which are then destroyed by tillage implements before sowing flax.

Before sowing, if necessary, the soil surface is leveled, for which light toothed harrows ЗБП-0.6А, plume-harrows ШБ-2.5, etc. are used, or leveling bars are used.

Poorly moistened and light-textured soils are rolled using smooth water-filled (ЗКВГ-1.4) or ringed rollers (ЗККШ-6А). On heavily moistened and heavy soils, it is recommended to carry out leveling with trailing harrows.

When carrying out pre-sowing tillage for flax, combined units are more effective: ripper-leveler – roller РВК-3.6 and leveler-chopper-packer ВИП-5.6, which allow high-quality soil preparation for sowing in one pass.

On well-prepared soils, field germination of flax reaches 70-80%.

Sowing

Seed preparation

Requirements for flax seeds are: purity – not less than 97%, germination – not less than 85%. Seeds should be full-bodied, leveled, shiny, oily to the touch. For fiber flax, contamination with seeds of camelina (Camelina), toriza (Spergula), and chaff (Lolium) is especially dangerous. The admixture of weed seeds in flax seeds should not exceed 180 pieces/kg. Seed material infested with quarantine weeds (for example, dodder (Cuscuta)) is not allowed to be used.

To combat anthracnose, fusarium, rust and other diseases, seeds before sowing or in advance (for (2) 5-6 months) are treated with chemicals using a semi-dry method at the rate of 0.5-1 l of water per 100 kg of seeds. At the same time, the moisture content of the seeds increases by only 0.4-0.5%. For dressing seeds with moisture, fentiuram, fentiuram-molybdate (300 g/100 kg seeds) are used in the form of wettable powders with various adhesive additives. It is also recommended to use preparations: tigam (300 g/100 kg of ​​seeds), 80% TMTD (300 g/100 kg of ​​seeds), granosan with dye (150 g/100 kg of ​​seeds). As adhesives, film-forming substances, for example, sulphite-alcohol stillage or acidic water, can serve. For 100 kg of seeds, take 1 kg of acidic water, 1 liter of ordinary water and a disinfectant according to the norm.

For pickling, special machines such as ПСШ-5, ПС-10А are used.

Before dressing to increase germination energy and field germination, flax seeds 10-15 days before sowing are subjected to air-heat treatment for 4-5 (7) days in open areas or 8-10 days in well-ventilated areas. To do this, they are scattered in a thin layer of 5-6 cm on tarpaulin panels or on clean, dry concrete sites. The seeds are stirred several times a day.

A good result is obtained by seed treatment with microfertilizers (boric acid, copper sulfate, ammonium molybdate, zinc sulfate, etc.).

Sowing dates

Sowing of flax is carried out in an early and short time (within 4-5 days). Sowing begins with the onset of soil ripeness and its heating at a depth of 10 cm to 7-8 ºC. Early sowing helps to increase the yield and quality of the fiber, while reducing the susceptibility of plants to fungal diseases and pests.

Delaying sowing by a week can reduce the yield of fiber and seeds by 10-20%.

According to the data of the Moscow Agricultural Academy Experimental Station for Flax Growing, the yield of trust at early sowing (May 13) of flax was 20% higher than with late sowing (June 9), and the quality of the fiber improved by five numbers. The damage of early crops by flax flea was 2.3%, while that of late crops was 3.46% (Vavilov; according to other sources, 34.6%, Kolomeichenko).

Flax germinated at low temperatures is more resistant to spring frosts. However, too early sowing in cold, wet and poorly prepared soil leads to a decrease in the yield of flax to the same extent as late sowing.

The sowing of oil flax is carried out simultaneously with the sowing of early spring crops.

Seeding methods

The best way to sow flax is narrow-row with a row spacing of 7.5 cm.

For sowing, flax narrow-row seeders СЗЛ-3.6, as well as СЛН-48А, СУЛ-48, aggregated with tractors of the 1.4 kN class are used. For uniform sowing of seeds, seeders are additionally equipped with ring trains.

To obtain flax seeds, wide-row (45 cm) or tape methods (45 × 7.5 × 7.5 cm) of sowing are usually used. For accelerated reproduction of new varieties and in dry conditions, the wide-row method is more effective, while the seeding rate is reduced by 2 times.

For sowing oilseed flax, ordinary grain seeders are used. The sowing method is narrow-row or ordinary ordinary.

Seeding rates

The generalized sowing rate of flax seeds is 20-25 million pieces or 100-120 kg per 1 ha.

Optimal seeding rates largely depend on the variety, for example, for a variety:

  • L-1120 – 25-30 million/ha of germinating seeds;
  • Svetoch – 27-29 million/ha;
  • K-6 – 24-25 million/ha;
  • Pskovskiy 359 – 21-22 million/ha;
  • Tvertsa – 20-23 million/ha;
  • Shokinsky – 25-30 million/ha.

In addition, the seeding rate is determined taking into account zonal conditions, the purpose of sowing.

In wet years, with increased seeding rates, lodging of plants is likely, which makes harvesting and primary processing of flax difficult. Thickened crops are not recommended to be done on poor soils, where flax turns out to be stunted. The seeding rate is increased by 10-15% on heavily weedy fields, as well as on heavy, floating soils, on which a smaller number of plants remain by the time of harvesting.

When growing flax for seeds, the seeding rate is reduced.

The seeding rate for oil flax seeds is 40-60 kg/ha.

With the bilateral appointment of flax-mezheumka (for fiber and seeds), the seeding rate is increased by 10-15 kg.

Seeding depth

The optimal sowing depth of flax seeds on heavy soils is 1.5-2.0 cm, on light soils – 2.0-2.5 cm.

Increasing the sowing depth significantly reduces the seedling density and flax yield. So, in the experiments of Moscow Agricultural Academy and Izhevsk Agricultural Institute at a seed sowing depth of 5-6 cm, the field germination of flax decreased to 42-50%.

The optimal sowing depth of flax seeds for bilateral use is 4-5 cm.

Stubble and joint crops

With the combine method, harvesting with spreading straw on flax, under flax, meadow fescue (16-18 kg/ha) or perennial ryegrass (20-25 kg/ha) can be sown.

White grass clover can be sown simultaneously with flax seeds. To do this, they are thoroughly mixed before sowing.

Seeding quality control

During the first passes of the unit, the sowing depth, the width of the butt row spacing, the seeding rate are checked in accordance with the requirements for the production of mechanized work in field crops.

The number of seeds consumed during the operation of the seeder at the control length of the passage of the unit at a given seeding rate (Q) is calculated by the formula:

Q = LBH/104,

where L is the length of the rut, m; B is the width of the seeder, m; H is the seeding rate, kg/ha.

Crop care

Care of crops of commercial fiber flax consists in:

  • post-sowing rolling;
  • harrowing (during the formation of a crust);
  • weed and pest control.

The listed agrotechnical measures are carried out taking into account specific conditions.

Harrowing to destroy the soil crust is carried out with light sowing, rotary or mesh harrows, as well as ring-spur rollers.

In addition to agrotechnical measures, the most important methods of caring for crops include the use of chemical means to control weeds, pests and diseases of flax. The damage they cause to fiber flax can reach 30% or more in some years.

According to All-Russian Research Institute of Flax data, in the presence of more than 200 dioecious weeds per 1 m 2 of crops, it leads to a decrease in yield even when fertilizers are applied.

To combat annual dicotyledonous weeds (white gauze (Chenopodium album), field yaruka (Thlaspi arvense), zebra pickle (Galeopsis speciosa), field tori (Spergula arvensis), wild radish (Raphanus raphanistrum), etc.), spraying with herbicides such as 2M-4X, 2M-4X 80%, which are applied in the amount of 0.6-1.2 kg. The consumption of the working solution when spraying with ОН-400 boom sprayers or others is 200-300 l, with the help of aircraft – 150-200 l/ha.

The optimal phase of development of flax crops for herbicide treatment is plant height from 5 to 8 (15) cm (herringbone phase). During this period, the leaves are located on the stems at an acute angle (10-30°) and are often covered with a wax coating, thus significantly reducing the negative effect of the herbicide on cultivated plants in comparison with the treatment at a later date.

The greatest effect of spraying crops is achieved in clear and dry weather at an air temperature of 15-17 °C. Cool weather (12 °C) slows down the penetration of the herbicide solution into weeds, while dry and hot weather increases, but at the same time causes flax to stick.

According to All-Russian Research Institute of Flax, the use of herbicide 2M-4X (0.75 kg/ha) in a mixture with ammonium nitrate (9 kg/ha) or urea (13 kg/ha) promotes good growth of flax and more complete cleansing of crops from weeds. the use of herbicide and nitrogen fertilizer , compared with treatment with one herbicide, increases the yield of flax seeds by 13-14% and fiber – by 12.8-27.7%.

According to the Department of Crop Production of the Moscow Agricultural Academy, the effect of spraying crops with herbicide 2M-4X (0.5 kg/ha) in a mixture with ammonium nitrate (12 kg/ha) is enhanced if microfertilizers are added to the mixture (boron 0.25 kg/ha, zinc and molybdenum at 0.1 kg/ha). At the same time, the fiber yield increases by 0.15-0.2 t/ha, seeds – by 0.13-0.15 t/ha. Such a joint action of the herbicide, ammonium nitrate and microfertilizers is associated with an increase in plant photosynthesis. In addition, the infection of flax with bacteriosis, fusarium, rust and other diseases is noticeably reduced.

Particular attention in flax-sowing farms should be given to the fight against creeping wheatgrass (Elytrigia repens), which in heavily infested areas can reduce the yield of flax fiber by 20-25% or more. Sodium trichloroacetate (TCA) is used to control this weed. The drug is applied no later than the first half of September, as wheatgrass “shilets” appear after peeling the soil from under grain crops or disking a layer of perennial grasses. The application rate of sodium trichloroacetate on sandy loamy soils is 20 kg/ha a.i. (or 23 kg/ha 90% of the preparation), on loamy soils – 30 kg/ha a.i. (or 34.5 kg/ha of 90% preparation). The same doses are used after autumn treatment.

According to the results of VNIIL experiments, the application of 30 kg/ha of sodium trichloroacetate before plowing leads to the death of 78.1% of the rhizomes of couch grass, and the increase in fiber yield reaches 13.6%, seeds – 10.8%.

Another notorious flax weed is flax chaff (Lolium remotum). Against it, the herbicide 40% triallat is used, which is applied 1-3 days before sowing or on the day of sowing before leveling the soil surface with harrows at the rate of 1.5-2.5 kg per 1 ha. Triallat reduces the infestation of flax seeds by chaff by 90-96%.

Care of flax crops should include the protection of plants from pests, especially the ubiquitous flax flea. Against the flea, 1-2 days before the emergence of seedlings, marginal and blockade treatments of crops with insecticides are carried out to a width of 3-4 passes of the unit. For processing, the preparation phosphamide Bi-58 is used in the amount of 0.8 kg/ha. For these, 80% chlorophos (0.8 kg/ha) can also be used.

When the number of flax fleas is more than 10 individuals per 1 m 2 in dry and hot weather, or more than 20 individuals per 1 m 2 in wet weather, the treatment is performed using boom sprayers. Fluid consumption 200-300 l/ha.

To control thrips, crops are dusted with 12% HCH dust (15-25 kg/ha) after the herringbone phase.

Harvest

The ripeness phase of fiber flax is divided into four phases:

  • green;
  • early yellow (early);
  • yellow;
  • complete.

Green ripeness (flax-green) comes after flowering. During this period, the stems and boxes are still green, only the leaves in the lower third of the plant begin to dry out and turn yellow. When the seeds are crushed, a milky liquid is released from them. Harvesting flax in the green ripeness phase produces a thin and shiny, but weak fiber. Such fiber can be used in the production of thin products (cambric, lace).

In the phase of early yellow ripeness, the leaves of the lower half of the plant stem fall off, the rest, with the exception of the apical ones, turn yellow. The boxes have green veins. Seeds in pods acquire a green-yellow color and a yellow spout (wax ripeness). Harvesting flax in this phase produces the best quality fiber: soft, silky and strong.

In the phase of yellow ripeness, all leaves turn yellow, remain only at the top of the stem, the bolls become brown, the seeds become light brown. Usually occurs 5-7 days after the early ripeness phase. The quality of the fiber in the phase of yellow ripeness begins to decline. The fiber of the lower part of the stem becomes coarse.

In the phase of full ripeness, all the leaves fall off, the stems and boxes become brown. The fiber collected in this phase is of poor quality: dry, hard, inelastic.

For timely harvesting of flax it is possible to use desiccation. This technique allows you to dry the plants on the vine and refuse field drying and ripening of plants in sheaves. Desiccation is carried out in the phase of early ripeness.

The harvesting of fiber flax by harvesters usually begins 2-3 days after the onset of the phase of early yellow ripeness (Karpets, 1984). Linen harvested during this period produces the greatest amount of high quality long fiber. Seeds by this moment are sufficiently formed and after ripening can be used for sowing (technical ripeness of flax).

Harvesting of flax in the phase of yellow ripeness is carried out upon receipt of seeds of breeding varieties of fiber flax in seed farms. In the phase of full ripeness, oil flax is harvested.

The period of technical ripeness of fiber flax is 8-10 days, but in hot weather it can be reduced. Therefore, the delay in pulling leads to significant yield losses: on average, for each day, the loss of fiber is 2-3%, seeds – 1.5%.

According to the data of the Moscow Agricultural Academy Experimental Station for Flax Growing, harvesting flax at the end of the yellow ripeness phase led to a decrease in the yield of long fiber by an average of 14.2% over 5 years compared to harvesting in the early yellow ripeness phase, and harvesting in the full ripeness phase by 21. 9%.

Flax harvesting is considered the most difficult and time-consuming work in flax growing – it accounts for 70-80% of all costs. Therefore, the use of efficient flax harvesting technologies is of great industrial and economic importance.

The traditional sheaf harvesting method, including pulling, field drying of sheaves in pasterns, threshing on threshing machines and manual spreading in the meadow, does not meet the objectives of the development of flax growing. A more advanced and efficient way of harvesting flax is the well-developed and proven for many years combine harvesting method.

The combine harvesting method allows you to perform several operations: pulling, stripping seed pods, loading a heap of vehicles, knitting flax straw into sheaves using a knitting machine for subsequent delivery to a flax mill (ЛКВ-4А combine) or spreading it on a flax in the form of a tape to obtain trust (harvester ЛК-4А).

Compared with the sheaf method, the combine method reduces the time for harvesting flax by 3-4 weeks, and labor costs – when spreading straw on a flax bed by 1.5-1.7 times or when putting straw in sheaves by 3-4 times. The efficiency of the combine harvesting method increases when several combines are used.

According to All-Russian Research Institute of Flax, the preparation of flax straw on a flax bed is almost comparable to the process of its maturation on meadow beds. Conditions on the flax can be improved by overseeding flax with perennial grasses ( meadow fescue , perennial ryegrass, white clover, etc.). The quality of trusts in this case increases by 1-2 numbers.

When harvesting flax with the help of ЛК-4А combines, the spreading of straw on the bed is carried out simultaneously with harvesting in the optimal agrotechnical terms – 20-30 days earlier than with the sheaf method.

In the process of straw maturation, approximately every 8-10 days it must be turned over with the help of mounted turners ОСН-1 for uniform maturation and prevention of overgrowing of straw with grass. The trust begins to rise when its moisture content is not more than 20%.

The lifting of linen stock with its tying into sheaves is carried out by a mounted pick-up ПТН-1. The use of a pick-up allows you to reduce labor costs compared to the manual method by 6 times.

With a combine harvesting method, a raw heap is obtained, which consists of 52-84% of boxes, 2-7% of seeds, 12-16% of mud and other impurities. The humidity of the heap is usually high – 60-65%, seed pods 40-50%. In order to prevent damage to seeds in boxes, a heap is evenly loaded into the drying sections with a layer of 1.1 m in floor dryers or 0.7 m in conveyor dryers and is immediately dried to a moisture content of 16-18% on the surface, for which installations are used, for example, ОСВ-60 with air heater ВГ1Т-400 or ВПТ-600. The temperature of the heated air should not exceed 45 °C. After 20-45 hours of drying, cold air is blown for 1.5-5 hours to reduce seed damage during heap processing. The following requirements are imposed on the process of drying and processing: loss of seed germination should be no more than 2%, crushing – less than 1%, irretrievable losses during processing should be no more than 3%. The threshing of the heap is carried out on a threshing fan МВ-2.5А. Seed moisture before threshing should be 10±2%.

In the culture of fiber flax, it is of great importance to bring the seeds obtained during harvesting to sowing conditions. To do this, farms carry out their cleaning on grain cleaning wind screen machines СМ-4, СОМ-300 and electromagnetic machine СМЩ-04. At flax seed stations, production lines from a complex of machines and equipment for processing and preparing seeds for sowing are used for this.

Compliance with the technology of drying seeds intended for sowing is important, since the loss of germination occurs due to the death of the embryo under the action of a heating temperature above the maximum allowable. The sensitivity of the embryo to high temperatures increases with increasing seed moisture. For shaft-type dryers, the optimal drying modes are determined (table).

Table. Recommended modes of drying flax seeds[2]Crop production/P.P. Vavilov, V.V. Gritsenko, V.S. Kuznetsov and others; Ed. P.P. Vavilov. – 5th ed., revised. and additional - M.: Agropromizdat, 1986. - 512 p.: ill. - (Textbook and textbooks for … Continue reading

SEED MOISTURE CONTENT BEFORE DRYING, %
LIMIT TEMPERATURE, °C
coolant
seed heating
13-15
65-70
42-45
15-17
60-65
38-40
17-19
55-60
35-38
over 19
50-55
32-35

Flax straw can remain on the farm for primary processing or be immediately delivered to harvesting stations and flax mills. For delivery to flax mills, straw must comply with the established requirements (GOST). The sheaves must be round or oval in shape with a diameter of at least 13 cm. The moisture content of the straw (to an absolutely dry mass) must be 19%, straw with a moisture content of more than 25% is not accepted by flax mills. Permissible weediness – 5%, with more than 10% weediness, straw is also not accepted.

The quality of flax straw is determined by the length (handful), strength, bast content, suitability, color, stem diameter. Depending on these properties, it may have the following numbers: 5.00; 4.50; 4.00; 3.50; 3.00; 2.50; 2.00; 1.75; 1.50; 1.25; 1.00; 0.75; 0.50. The quality of delivered straw is assessed in daylight by comparing the selected samples with seasonal standard samples.

Primary processing of flax

In order to reduce losses and obtain the greatest amount of high-quality fiber from straw, it is divided into 2-3 grades according to length, thickness, color and other qualities. Plants affected by diseases are isolated in a separate fraction.

The main operations of primary processing of flax include:

  • preparation of trust straw by spreading or rinsing;
  • drying trusts;
  • wrinkle;
  • fluttering.

At present, 75-80% of the trusts are prepared on farms by spreading straw on the beds. The industrial technology of fiber flax cultivation provides for the sale of 50-70% of flax products to flax mills in the form of flax straw. Flax straw, when spreading, turns into trust under the action of an aerobic fungus – Cladosporium herbarum Zin. (aerobic straw lobe). The trust is best aged when spreading in August, when the weather is warm (18 °C) and humid with heavy dews. The duration of maturation under such conditions this month is 3-4 weeks, in later periods of spreading it increases to 5-7 weeks. By the end of the maturation, the stems of the trusts become gray. At this time, to determine the end of aging, sampling is carried out – “torture” (handfuls from different places, at least 2 kg). The samples are dried, processed on a pulper and ruffled.

2-2.5 tons of flax straw are spread on 1 hectare. Trusts from such straw are obtained by 20-25% less (slate trust).

After aging, the trust is placed in cones to dry. In case of rainy weather, drying is carried out in special dryers and rigs.

The best way to obtain trusts is considered to be a water soak of straw in special soaks, and especially in warm water (thermal soak).

Thermal urine is carried out in installations consisting of several soaking pools, devices for heating water and other equipment. The decomposition of pectin substances in the water lobe occurs under the action of anaerobic bacteria Bacillus felsineus Carbone, Granuiobacter pectinivorum Bejerinc et Van. and others (anaerobic lobe of flax straw).

Wetting basins are loaded with sheaves of straw in a vertical position and immediately filled with water at a temperature of 36-38 °C. After 9 hours, part of the urination liquid is drained, fresh warm water is added instead. 6 hours later, a slow flow of warm water is established through all pools until the lobe is completed. The duration of the heat lobe is 3-5 days. Upon completion, the trust is washed with water, squeezed on presses and dried.

Dew or water lobe, as well as chemical treatment in alkaline solutions, can also be used to isolate the fiber.

To isolate pure fiber from trust, it is necessary to remove the fire, that is, the wood of the stems. This operation is carried out with the help of special roller mills. After that, raw fiber is obtained, which is subjected to additional separation from the remains of the fire on scutching machines.

After drying, the trust (slate and monets) is subjected to crushing on МЛКУ-6А pulpers, from which fiber is obtained. The fiber is subjected to processing – scutching – on flax scutching machines ТЛ-40А. On average, flax fiber contains 25% of the total fiber, long – no more than 18-20%. Part of the fiber goes to waste, from which, with the help of tow-making machines КЛ-25А, a short “tow” fiber is obtained. Usually, all these machines are part of one scutching and scutching unit, the daily output of which is 600-800 kg of fiber.

When handed over to flax mills, the trust must be gathered into sheaves of hand or machine knitting. The sheaves should be uniform in length and degree of maturation or soaking, and the stems in the sheaves should be placed with butts in one direction. The moisture content of the straw should be no more than 20%, weediness – no more than 5%, fiber content – no less than 11%, sheaves diameter – no less than 17 cm.

Linen weed (soaked straw), depending on the fiber content, strength, handful length, suitability, color, separability and diameter of the stems, is divided into numbers: 4.00; 3.50; 3.00; 2.50; 2.00; 1.75; 1.50; 1.25; 1.00; 0.75; 0.50. In accordance with the technical specifications (GOST), an OOV device should be used to determine the fiber separability, to determine the fiber content – ПК-2, sheaf length – ДЛ-3.

Linen fiber, upon delivery to procurement points, should be tied into waders of 3-4 kg with a flax length of up to 70 cm. At a distance of 1/3 from the top, each wader is tied twice with a belt made from the same fiber. Rated humidity of torn flax to absolutely dry mass should be 12%. Upon acceptance, an organoleptic analysis of ragged flax is carried out by comparing it with standard seasonal samples. Worn flax, depending on the quality, is usually divided into numbers: 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 18, 20, 22, 24, 26, 28, 30, 32. Linen the fiber should be clean from the fire, strong, long, thin, soft, greasy to the touch, heavy and uniform in color (light silver, white). The yield of pure fiber is usually about 15% by weight of straw or 20% by weight of straw.

Industrial technology of fiber flax cultivation

All-Russian Research Institute of Flax, together with the Ukrainian Research Institute of Agriculture and the Belarusian Research Institute of Agriculture, developed an industrial technology for the cultivation of fiber flax, which was introduced on more than a quarter of all commercial crops. The technology is designed to produce at least 550-800 kg/ha of flax fiber and 500 kg/ha of seeds, in addition to reducing labor costs by more than 2 times.

Industrial technology includes:

  • concentration of crops in fiber flax farm in 2-3 crop rotations;
  • placement of flax after cereal crops;
  • introduction of scientifically based norms of mineral and organic fertilizers in
  • the crop rotation;
  • basic tillage according to the semi-fallow type;
  • improved pre-sowing tillage;
  • sowing at the optimal time with seeds of class I and II with a seeding rate of 18-22 million/ha of viable seeds;
  • application of an integrated system of measures to combat diseases, pests and weeds;
  • pre-harvest desiccation;
  • mechanized cleaning;
  • implementation of at least 50% of the crop in the form of straw according to the “field-factory” scheme. At the same time, as the experience of All-Russian Research Institute of Flax has shown, the roll cleaning technology deserves attention.

Organizational measures are based on the contract, the creation of harvesting and transport complexes for harvesting flax in the optimal time and reducing the loss of flax products.

Technological operations are recommended to be performed by machines for:

  • dressing seeds ПСШ-5, ПС-10А, ОПШ-15;
  • fertilizer application – ПОУ, РТТ-4.2А, 1-РМГ-4, ЛДГ-10А, ЛГД-15А, БД Т-3, ПЛН-8-40, ПЛН-4-35, ПЛН-3-35, КПС-4-03, ЗКВГ-1,4, РВК-3,6;
  • sowing – СЗЛ-3,6;
  • cleaning – ЛК-4А. ЛКВ-4А, ПТН-1, ОСН-1, ПНП-3, ПСП-3, ВПТ-600, ТЛН-1.5А, Т-25А, МТЗ-80, ТАУ-1,5, МВ-2.5А, МЛ-2.8П, trailer 2ПТС-4М.

Thus, intensive technology, using intensification factors, and, despite the significant costs of fixed assets in the development of technology, allows the most rational use of resources and obtaining flax products with greater efficiency.

For example, in the collective farm “Bolshevik” of the Torzhok district, according to the industrial technology of flax in 1983, 9.2 centners per hectare were obtained from a total area of ​​330 hectares with labor costs for obtaining 100 kg: seeds – 12.2 man-hours; straw – 2.5 man-hours; trusts – 5.3 man-hours

Features of agricultural technology of oil flax

Oilseed flax is placed in a crop rotation after fertilized winter crops, perennial grasses, legumes, corn, potatoes and other crops.

Autumn processing is carried out as early as possible, before which it is recommended to peel the soil. The main tasks of spring processing include the preservation of moisture in the soil and weed control.

When fertilizing oilseed flax, phosphorus and potash fertilizers (30–45 kg/ha of phosphorus and potassium) are applied for autumn tillage, and nitrogen fertilizers (25–30 kg/ha of nitrogen) for presowing cultivation. According to All-Russian Research Institute of Oilseeds data, the introduction of granular superphosphate into the rows during sowing gives a good result. Seed yield increases by 2.9 kg/ha.

Sowing of oil flax is carried out simultaneously with early spring crops. The sowing method is the usual ordinary or narrow-row. On weedy soils, wide-row sowing is used with row spacing of 45 cm. The seeding rate is from 30 (on wide-row) to 80 kg/ha. With double-sided use of flax (for seeds and fiber), the seeding rate is increased by 10-15 kg. Sowing depth 4-5 cm.

Oil flax is harvested for seeds in the phase of full ripeness. Cleaning is carried out by grain combines. With two-sided use of the crop – in the phase of yellow ripeness with a cut height of 10 cm and a reduced number of drum revolutions per minute to 800-1200. If flax straw is spread on a flax field, the bottom of the stacker is removed from the combines. If the straw is spread elsewhere, the harvester collects the straw into piles and then it is transported to the meadows and spread over the surface with a layer of no more than 15 cm. In damp and warm weather, flax stalks can mature for 10-12 days.

The separation of fiber from the trust is carried out with the help of mills and shakers (construction tow). To isolate the spinning fiber, a tow-making machine КЛ-25А is used.

Sources

Crop production / P.P. Vavilov, V.V. Gritsenko, V.S. Kuznetsov and others; Ed. P.P. Vavilov. – 5th ed., revised. and additional – M.: Agropromizdat, 1986. – 512 p.: ill. – (Textbook and textbooks for higher educational institutions).

V.V. Kolomeichenko. Crop production / Textbook. — M.: Agrobusinesscenter, 2007. — 600 p. ISBN 978-5-902792-11-6.

Fundamentals of agricultural production technology. Agriculture and crop production. Ed. V.S. Niklyaev. – M .: “Epic”, 2000. – 555 p.

Cotton

Cotton is an agricultural fiber and oilseed crop.

Economic importance

Cotton fiber is the main type of plant raw material for the textile industry. Various fabrics are made from cotton fiber of long-staple varieties: chintz, satin, knitwear, flannel, batiste and others, in addition, it is used for the production of threads and cord. Mixed with wool or chemical fibers, cotton fiber is used to produce a wide variety of fabrics.

The down of seeds (lint or linter) is used for the manufacture of hygroscopic cotton wool, especially durable grades of paper, film, plastic, nitro-varnishes, and artificial leather.

Cotton cake can serve as a good concentrated feed for farm animals. The protein content in it reaches 40%. It is fed in small quantities (2-3 kg per day for
per head of cattle), as it contains the poisonous substance gossypol. Pigs should not be fed cake.

The peel (husk) of seeds serves as raw material for the production of ethyl and methyl alcohols, glucose, furfural, lignin, resins, feed proteins. Acetic acid, paper, biofuels are obtained from the stems and flaps of the boxes. From the leaves and bark of the stems – citric acid (the content in the leaves is up to 10%) and malic acid, resins. Plant residues can be used as organic fertilizer.

Cotton raw materials are used to make safety glass, artificial felt, fire hoses and other products.

From 1 ton of raw cotton can be obtained: (320) 340-350 kg of fiber, 570-580 kg of linted seeds, 30-40 kg of lint, 20-30 kg of other waste. When processing this amount of cotton seeds, the following can be obtained: 98-110 kg of refined oil, 20 kg of laundry soap, 225-230 kg of cake, 210-230 kg of husks.

The output from 1 kg of cotton fiber fabrics is: 12 m of chintz or 20 m of cambric, or 140 spools of thread.

Cotton is a valuable honey plant.

As a tilled crop, crop rotation is of great agrotechnical importance.

In addition to the spinning crop, cotton is also considered as one of the main oilseeds. Cotton seeds, whose share of the total mass of the raw yield reaches 65%, contain (18) 20-27% oil, including 35-40% in the kernel. The oil is suitable for eating and for producing margarine, drying oil, phytin, stearin, glycerin, soap.

Crop history

Cotton has been cultivated since ancient times. It has been grown since 3000 BC. in India and China and was used to produce spinning fiber. Approximately 500 BC cotton penetrated from China to Egypt, and in the IV-V centuries. cotton growing began to develop in Central Asia and Iran, in the 9th-10th centuries. high-quality fabrics were made from cotton fiber.

In the XIII century. cotton appeared in Transcaucasia.

In America, cotton appeared independently in Mexican and Peruvian cultures and has been known for several millennia.

The industrial processing of cotton fiber increased dramatically in the second half of the 18th century, after the invention of machine spinning and the cotton gin. In the 19th century cotton growing provided 73% of all spinning raw materials, and in the 20th century. – over 85%.

Cotton growing in Russia developed very quickly. In 1922 V.I. Lenin approved the “Regulations on the state organization of cotton growing, the cotton ginning industry and cotton procurement.” In 1929, measures were taken to free the USSR from dependence on foreign supplies of raw cotton. Special attention was paid to the development of cotton growing in the republics of Central Asia and Transcaucasia. As a result, within 3 years, the import of cotton to the USSR was greatly reduced and amounted to only 7% of the country’s need for cotton fiber, and in the prewar years it was completely stopped.

The USSR was the northernmost country in the world where cotton was grown. After the Great Patriotic War, the USSR ranked first in world agriculture in terms of yield and quality of cotton fiber.

Chemical composition

The chemical composition of the green mass, mowed in the phase of mass flowering:

  • water – 65-70%;
  • carbohydrates – 17%;
  • protein – 2.5%;
  • fats – 0.8%.

Also in the green mass contains a large amount of calcium and phosphorus.

Cultivation areas and yield

The world area occupied by cotton crops in 1984 was 33-34 million hectares, and the gross harvest of raw cotton was 42-45 million tons. The main cotton-growing countries of the world were the USSR, the USA, China, India, Pakistan, Brazil, Mexico , Egypt and Turkey. They accounted for approximately 80% of all raw cotton produced in the world.

In the early 2000s, cotton was grown in about 60 countries around the world. The total sown area was 35 million hectares, including:

  • India – 7.5 million hectares;
  • USA – 4.5 million hectares;
  • China – 4.8 million hectares;
  • Brazil – 1.9 million hectares;
  • Pakistan – 1.8 million hectares;
  • Egypt – 0.6 million hectares.

In the USSR, the main cotton-growing regions were the republics of Central Asia: Uzbekistan, Turkmenistan, Tajikistan, Kyrgyzstan, Kazakhstan and Transcaucasia (Azerbaijan). The sown area in the USSR reached 3.2-3.3 million hectares, and the yield of raw cotton in 1984 was 2.3-2.6 tons/ha, the gross harvest was 8.6 million tons.

Record yields reached 4-5 t/ha.

For the period up to 2000, the USSR planned to achieve a harvest of 2.8-3 million tons of cotton fiber and 9.1-9.4 million tons of raw cotton. In addition, it was planned to improve the quality of the fiber, its output and reduce losses.

Botanical description

Cotton (Gossypium) belongs to the Malvaceae family (Malvaceae). A perennial plant, but more often, especially in temperate regions, it is cultivated as an annual crop.

An adult plant is a bush with a height of 90 to 130-180 cm.

Root

The root is taproot, well developed, penetrates the soil to a depth of 1.5-2 (3) m. In the upper part, many lateral roots depart from it. Horizontally extends to 1.5-2 m.

In the first month of plant development, the root system grows very quickly. Before the budding phase, the main root develops especially intensively, while after this phase, the lateral roots develop. In the first two weeks, the growth of the main root averages 2.5-3.2 cm per day, and the total growth of lateral roots reaches 30-45 cm.

Stem

The stem is straight, branching, strong enough, woody (rough) in the lower part, covered with hairs.

There are 2-3 buds in the axils of the leaves. Those of them that are in the axils of the first leaves usually remain dormant, and branches begin to form from the buds of the axils of subsequent leaves, more often 3-5 leaves.

Branches

The branches are divided into growth (monopodial), or monopodia, and fruit (sympodial), or sympodia.

Monopodia are formed in the lower part of the stem and depart from it at an acute angle. Monopodia grow in a straight line and are usually stronger than sympodial ones.

Fruit branches on the stem are located above the growth branches. They form a more obtuse angle with the stem and grow articulated, along a broken line. Sympodia are peduncles, on which fruits (boxes) then appear.

Cotton
Cotton bush: 1 - main stem; 2 - box; 3 - fruit branches; 4 - growth branches

The number of monopodial branches on the main stem before the formation of the first sympodium is different and depends on the forms and varieties of cotton species, as well as on growing conditions.

In the tropics, there are forms of cotton, in which the number of monopodial branches is from 15 to 40 pieces. This type of cotton branching is called monopodial.

A typical cotton plant is treelike. Its sympodial branches form high and bloom very late.

In the conditions of the countries of Central Asia, there are usually only 2-3 monopodia on a cotton bush before the formation of the first sympodium. This type of branching is called sympodial. The height of the laying of the first sympodial (fruit) branch on the main stem is one of the signs of the precocity of cotton.

There are forms of cotton that do not form branches, and the fruits sit on shortened stalks, 1-2 in axils of the leaves of the main stem. This type of branching is called zero. Bushes of this type are very compact. Such forms of cotton were bred in the Soviet period and were used to produce fine-staple cotton.

Cotton varieties differ in the number and length of internodes of fruit branches. Some varieties have fruit branches with one internode, at the end of which all the buds give buds and boxes, so the branch stops further growth. This type of branch is called limiting. The cotton bush with the limiting type of branching has a compressed columnar shape.

Fruit branches with several internodes are of the unlimited type.

Cotton branch
Fruit branch (sympodium) of the limiting type
Fruit branch of cotton
Fruit branch (sympodium) of unlimited type

Depending on the length of the internodes, the unlimited sympodial branches are divided into subtypes:

  • I – with shortened internodes 3-5 cm;
  • II – with average internodes 6-10 cm;
  • III – with long internodes 11-15 cm;
  • IV – with very long internodes 16-25 cm.

A subtype with very long internodes is characteristic of Soviet varieties of fine-staple cotton.

The length of the internodes of fruit branches is an important varietal trait that determines the total length of the branches, the degree of spreading or compactness of the bush. The longer the internodes, the longer the branches and spreading of the bush and, conversely, the shorter the internodes, the shorter the branches and the more compact the bush. The large spreading of the bush creates some difficulties in inter-row tillage and harvesting.

In the USSR, forms of cotton with an unsaturated type of fruit branches were usually grown. Cotton with a marginal type of branches is considered to be less productive and produces fiber of a slightly worse quality.

In the axils of the leaves of monopodial branches, branches of the second order can form, and, just like on the main stem: in the axils of the first 2-3 leaves, the branches usually do not form, and the buds remain dormant here. Monopodia can form from the axils of the next 2-3 leaves, and only sympodia can form from the axils of the next leaves. Thus, in its development, the monopodial branch, as it were, repeats the development of the main stem.

The later the cotton plant is, the more often it forms monopodial branches of the second order. In early ripening varieties, only sympodia are usually formed as branches of the second order on monopodial branches. The total number of fruit branches on the stem is 16-18.

Leaves

Leaves vary in size and shape on the same plant. The first 2-3 leaves developing on the main stem are whole, extreme, heart-shaped. The rest of the leaves on this stem and branches are lobed. The number of leaf lobes varies in different varieties and varies from 3 to 7.

On the main stem and on the growth branches, the leaves are located at each node, while on the fruiting branches – opposite each bud.

Inflorescence

The flower is large, consists of five petals fused at the base, yellow, cream or white, depending on the variety. At the base of the petals of some types of cotton, for example, Peruvian or goose, there is a raspberry-red spot.

Stigma 3-5-lobed, large. There are many stamens. Anthers yellow, cream or orange. Calyx green, underdeveloped.

The flower has three large bracts.

Mainly self-pollinator. Cross-pollination is rare.

Fruit

The fruit is a round-ovoid capsule. The size of the box depends on the number of flaps (nests), which can be 3-5. In one nest there can be from 5 to 10 seeds, in one box – 25-40 seeds.

When ripe, the box cracks at the seams, and the valves in most species open, while raw cotton is exposed, which consists of seeds covered with long (fiber) and short (down) hairs.

The mass of dry raw material in one mature box is from (2) 5 to 8 (10) g and depends on the variety and growing conditions. The mass of raw cotton accounts for 30-40%, for downs (linter) – 0.2-1.5%. Strong, well-developed bushes can produce over 100 open boxes. Opening stops at frosts of -3…-4 °C, which usually occur in the main cotton-growing regions at the end of October.

Seeds

Seeds are ovoid, with a very large number of fibers – up to 7-15 thousand, 9-12 mm long, 6-8 mm wide. After removing the fibers from the seeds, they are left with a downy layer of short fibers. It accounts for 3-4% of the mass of seeds.

The seeds are covered with two shells: outer (peel) – lignified dark brown and inner – membranous. The kernel (without shell) consists of two cotyledons, rudiments of root and stalk.

Weight of 1000 seeds (80) 90-150 (160) g.

Types of cotton

The genus Cotton (Gossypium) includes 35 species, of which 5 are cultivated and 30 are wild, in addition, the genus has many forms and varieties. Two types were cultivated in the USSR:

  • ordinary cotton, or Mexican (medium fiber), – Gossypium hirsutum L .;
  • cotton Peruvian, or Egyptian (fine-fibered), – Gossypium peruvianum Gav. (Gossypium barbadense L.).

Herbaceous cotton (guza) – Gossypium herbaceum L. – is considered unproductive and was not grown in the USSR.

Tree-like cotton, or Indochinese – Gossypium arboreum L. and three-pointed cotton – Gossypium tricuspidatum Lam. – cultivated in tropical regions.

Cotton ordinary (medium fiber)

Cotton ordinary (medium fiber) comes from Mexico.

In culture, this semi-shrub reaches a height of 1-1.5 m. The stem is strong with developed branches, which are pubescent with one tier of hairs.

Leaves 3-5-lobed. The blades are medium, shortened triangular.

The flowers are yellow, medium in size, there is no spot on the petals of the corolla, they open well.

The boll is round, large, with a beak at the top, 4-5-leaf (3-5 nested), the surface is smooth, when ripe it opens wide, 5-11 seeds in each nest.

Seeds are covered with down, consisting of dense short hairs. The fiber is white, 30-35 mm long, 17-20 microns thick. Fiber yield 35-38 (40)%. The fiber quality is high. Metric number 4200-5500.

Cotton is the most widespread species in all cotton-growing countries. Most of the cultivated varieties belong to this species and are characterized by precocity and cold resistance.

Peruvian cotton (fine fiber)

Peruvian cotton (fine fiber) comes from Peru.

It is a semi-shrub with a height of 1 to 3 m with a large number of long, hairless branches.

The leaves are 3-5-lobed, the lobes are elongated-triangular in shape.

The flowers are large, creamy, have a crimson-red spot on the petals of the corolla.

The boll is cone-shaped, large (but smaller than that of medium fiber cotton), with an elongated top, the surface is finely pitted, when ripe it opens wide, 3-4-leaf, 5-8 seeds per nest.

Seeds are almost bare, there are almost no downs. Fiber yield 31-34%. The fiber is strong, long 39-41 mm, of the highest quality, 12-18 microns thick, metric number 6000-7500, silky, has high spinning qualities.

Fine-staple cotton is characterized by a longer growing season and high heat requirements, so its varieties are grown in the warmest countries and regions.

Technological properties of cotton fiber

Cotton fiber is an elongated cell of the epidermis of the peel, slightly twisted, curving and covered with a thin layer of wax, which gives the fiber a shine. The ratio of cell thickness to its length is 1: 1500-2000. There is a cavity inside the fiber. Usually the fiber is white, in some varieties it can be cream, greenish or brown.

The fibers of the seed down are also formed from the cells of the outer epidermis of the peel, but their length is much less.

After cracking the boxes, the fibers dry quickly, as if flattened, while acquiring the shape of a ribbon. At the same time, they twist, become spirally twisted. Sometimes there are overripe fibers with thick walls. When dried, such fibers do not twist and remain rounded in cross section. In immature or immature fibers, when dried, the walls are easily flattened, but their crimp is weak, under a microscope they look like flat ribbons. Such abnormally developed fibers are called “dead fibers” in the textile industry.

In a well-developed box, not only abnormally developed fibers can be present, but also whole voles, that is, seeds with fibers sitting on it, which are formed due to the infertility of some ovary ovules. The fiber of the fly begins to form on the day of flowering, before fertilization. But the development of unfertilized ovules and the fibers that have begun to develop on them quickly stops, and they die off. Dead ovules, when dried, are nodules with short fibers, they are called small auks.

In addition to the small uluk, when the fertilized ovules die in the phase of a more or less developed embryo, a large uluk, that is, an underdeveloped volulet, can form.

The formation of small and large uluk occurs primarily due to improper nutrition of the plant and its individual parts. Most often this is due to the low level of agricultural technology and cotton diseases, especially wilt.

Increased volatility of raw cotton is usually noted in the first cone and peripheral cones, starting from the 4th-5th. Within one box, lucidity is observed at its base and in the lower parts of the lobules.

The formation of uluk leads to a decrease in the yield of raw cotton and loss of fiber quality. In different varieties of cotton, the mass of uluk varies from 0.7 to 1.2%.

Technological characteristics

The quality of cotton fiber is characterized by various technological characteristics, the main of which are the following:

  • fiber yield;
  • fiber length;
  • average breaking load (fiber strength);
  • linear density (metric number);
  • breaking length;
  • fiber maturity.

Technological characteristics (properties) of the fiber determine the quality of fabrics made from it. The thinner, stronger and longer the fiber, the more valuable it is, and the higher the quality of the fabrics produced from it.

The yield of fiber is the ratio of the mass of the fiber to the mass of the raw cotton from which it is obtained and expressed as a percentage. The yield of fiber depends on the growing conditions and the location of the bolls in different tiers of the cotton bush. The output of fiber from the boxes of the lower tiers is 2-4% more than from the upper tiers.

Fiber length – the distance between the ends of the fiber in the straightened state. Expressed in millimeters.

The average breaking load (strength) of the fiber is the maximum force that the sample can withstand before breaking. It is expressed in newtons (N) or gram-forces (gs). Characterizes the amount of load that one fiber can withstand before breaking. The average breaking load of the fiber depends on the grade and is usually 0.004-0.006 N or, respectively, 4-6 gf.

The linear density (metric number) of the fiber indirectly characterizes the fineness of the cotton fiber. It corresponds to the total length of all fibers in 1 g of fiber. Expressed in meters. So, for grade 108-f, the metric number is 5550, which means: the length of all fibers of 1 g of fiber is 5550 m. The greater the linear density of the fiber, the thinner it is. The metric number of fiber of different grades varies from 5000 to 8000.

The breaking length of the fiber is a complex indicator equal to the product of the strength of the fiber and its metric number. For example, with a fiber strength of 0.0049 N (4.9 gf) with a metric number of 5200 m, its breaking length will be 25,480 m (5200 m x 4.9 gf), or 25.48 km. The breaking length is expressed in kilometers. Physically, the characteristic is the length of such an imaginary fiber, which is torn under the action of its mass. The greater this characteristic, the stronger the fibers, and, accordingly, the yarn.

The maturity of the fiber reflects the filling of the fibers with cellulose. The characteristic is determined by the thickening of the walls and the reduction of the channel. An increase in maturity leads to a change in the basic properties of the fiber: its strength, linear strength (thickness) and the degree of dyeing increase.

Technological properties of cotton fiber differ on the same bush. Thus, the fiber yield decreases from the first bolls to the next. In the box itself, in each lobule, medium bats have a longer and stronger fiber. The fibers also vary within the bat. The longest fibers are located on the chalase of the seed, while the short ones are located at the micropyle end. The degree of fiber maturity decreases from micropyle to chalase.

For industrial use, a fiber that is more uniform in terms of technological characteristics is important.

The technological properties of the fiber depend on the hereditary characteristics of the varieties, soil and climatic conditions and cultivation methods. The most variable is the length of the fiber, which changes, for example, from irrigation and fertilization.

Types of cotton fiber

The Central Research Institute of the Cotton Industry was proposed to conditionally divide the entire range of cotton fiber into seven types, for each of which the approximate demand of the cotton industry (USSR) was established.

Fiber types I, II and III are obtained from varieties of fine-staple cotton. These varieties are late ripening and are cultivated only in the southern regions of the countries of Central Asia on relatively small areas (10% of all cotton crops). From the fiber of these varieties, especially thin and strong fabrics are obtained – satin, batiste and high-quality knitwear.

Fiber IV, V, VI and VII types are produced from varieties of medium staple cotton. These varieties are characterized by greater precocity and yield. They account for about 90% of all cotton sown areas. Type IV fiber is similar in quality to type III. It is used for the production of thread, voile and other fabrics. Type V fiber (basic) is used to produce the most common fabrics – linen, dress, lining and others. Suit and fleece fabrics are made from type VI fiber, they are also mixed with wool. Type VII fiber is not planned, as its quality does not meet the requirements.

Table. Types of cotton fiber[1]Crop production/P.P. Vavilov, V.V. Gritsenko, V.S. Kuznetsov and others; Ed. P.P. Vavilov. – 5th ed., revised. and additional - M.: Agropromizdat, 1986. - 512 p.: ill. - (Textbook and textbooks for … Continue reading

FIBER TYPE
FIBER LENGTH, MM, NOT LESS THAN
MINIMUM METRIC NUMBER
FORTRESS, GF, NOT LESS
RELATIVE BREAKING LOAD, GF/TEX
I
40-41
7900
4,7
37,0
II
38-39
7300
4,7
34,0
III
37-38
6800
4,7
32,0
IV
35-36
6000
4,7
28,0
V
33-34
5600
4,7
26,5
VI
32-33
5000
5,0
25,0

Biological features

Temperature requirements

Cotton seeds begin to germinate at a temperature of 10-12 °C, but the optimum temperature is considered to be 20-25 °C. Even small frosts down to -0.5 … -1 °C lead to the death of seedlings. The minimum temperature required for the emergence of cotton seedlings is 14-15 °C, for the formation of generative organs and flowering – 20 °C.

The optimum temperature for plant development is 25 °C. A higher need for plants in heat up to 26-30 °C falls on the period of flowering and budding.

Lowering the temperature below 10-12 °C results in a short or unripened cotton fiber.

The sum of active temperatures for early-ripening varieties of cotton is 3000 °C, mid-ripening – 3400 °C, late-ripening – 4000 °C.

Moisture requirements

Cotton is considered a relatively drought-resistant plant.

Due to the deep penetrating root system, plants make good use of the water of the subsoil layers.

Cotton can be grown in areas with an annual rainfall of 350-400 mm, but under these conditions the yield is very low.

Transpiration coefficient (400) 500-600 (800).

The greatest need for moisture falls on the period of flowering – fruit formation.

Higher air humidity contributes to the production of a long and thin fiber.

It responds very well to irrigation, while the yield increases sharply. In the conditions of the USSR, cotton was cultivated only with irrigation. To obtain good yields, cotton crops must be provided with 5-8 thousand m3/ha of water.

Soil requirements

In the countries of Central Asia and Transcaucasia, cotton is cultivated on soils characteristic of these regions: sierozems, sierozem-meadow and meadow-marsh. Light fertile soils with a pH of 7-8 are considered optimal.

Fields with a close occurrence of groundwater and with high acidity of the soil are of little use.

Cotton is able to tolerate slight salinity, especially towards the end of the growing season.

Light requirements

Cotton is a light-loving plant with a short day, so the orientation of the leaf blades changes during the day: during the day the blades are facing the sun, at night they fall in the shade.

Scattered light leads to a delay in the development of plants and an increase in the vegetative mass.

Direct and too bright light, together with exposure to high temperature and dry air, often reduces assimilation.

Vegetation

In cotton, the following vegetation phases are distinguished:

  • seedlings;
  • budding;
  • bloom;
  • maturation.

Seed germination begins with the absorption of 70-80% of their mass. First, the root starts to grow, then the curved hypocotyl knee of the stem, which brings the cotyledons to the surface of the soil.

Cotyledons appear on the soil surface under favorable conditions 5-6 days after sowing, and 8-10 days after that the first true leaf is formed. Each subsequent leaf appears after 3-5 days.

When 7-8 true leaves are formed in the axil of the 4-5 (6)-th leaf or slightly higher, the first fruit branch with a bud is formed. This moment is considered to be the beginning of the budding phase. From the moment the first leaf appears to the beginning of budding, (20) 25-30 days pass.

The formation of buds on a bush occurs in two directions: along the fruit branch (horizontally) and upward in a spiral.

In accordance with the timing of the formation of buds, flowering also takes place. The period from the development of the first bud to the opening of the first flower is 25-35 days, by this time 9-10 fruit branches are formed.

It has been established that higher yields of raw cotton can be obtained with early flowering and fruit formation.

Flowers open in the morning. The petals of the corolla at this time have a light yellow color. In the afternoon, the corolla turns red, and in the evening, withering, it closes. The next day, the corolla turns purple and falls off.

The opening of flowers in the bush occurs from the bottom up, in groups or cones. The first cone includes the first three flowers, which are located on the three lower branches closer to the stem. The second cone consists of the second flowers of the first three branches and the first flowers on the 4th, 5th and 6th branches. The third cone consists of flowers of the 1st, 2nd and 3rd branches, the second flowers of the 4th, 5th and 6th branches and the first flowers of the 7th, 8th and 9th branches, etc.

Cotton flowering scheme
Cotton flowering scheme: Roman numerals show the numbering of flowering cones, Arabic - the numbering of branches.

Flowering in an ascending line, that is, from branch to branch, occurs at intervals of approximately 2-3 days (short queue), while along the same branch – at intervals of 5-7 days (long queue). The duration of short and long flowering lines depends on the varietal characteristics of cotton, growing temperature, agricultural technology, etc.

The period from the flowering phase to the opening of the boxes is (45) 50-65 days. The external formation of the box ends 25-35 days after fertilization, but for the maturation of seeds and the formation of fiber, another 25-30 days are needed, during which nutrients are reutilized from the vegetative organs of the plant.

The opening of boxes on one bush often stretches up to 2 months. Clear and warm weather accelerates this phase and, conversely, cool weather slows it down.

The entire period from sowing to the opening of the first box, that is, the beginning of the ripening phase, is:

  • for Soviet varieties of medium staple cotton – 130-140 days;
  • for Soviet varieties of fine-staple cotton – 145-160 days.

The duration of interphase periods for the most common group of mid-ripening varieties is (Vavilov):

  • from sowing to germination 14-16 days;
  • from germination to the beginning of the formation of the basket 37-43 days;
  • from the beginning of the formation of the basket to flowering 27-30 days (according to other sources, 50-60 days after germination, Kolomeichenko);
  • from flowering to ripening 44-50 days.

The total duration of vegetation for this group of sunflower varieties is 120-140 days. Depending on the variety or hybrid and growing conditions, seeds may ripen in (70) 80-120 (140) days after germination.

In the first period of its development (2-3 pairs of leaves), sunflower plants develop relatively slowly. At this time, they are easily drowned out by weeds . However, then the growth accelerates and reaches its maximum, which is 3-5 cm per day, in the period from the formation of the basket to the beginning of flowering. In the flowering phase, growth in height slows down and stops completely by the end of flowering.

The beginning of the formation of the basket in early maturing varieties of sunflower in the conditions of the South-East of Russia falls on 2 pairs of leaves, in mid-season – at 3-5 pairs. The laying of the basket in mid-season varieties begins in the conditions of the Krasnodar Territory with 5 pairs of leaves.

Flowering of one basket lasts 8-10 days, and growth – until it turns yellow. The basket grows most intensively within 8-10 days after the end of flowering. The filling of achenes lasts for 32-42 days from the time of their fertilization.

Simultaneously with the growth of the plant in height and the formation of a basket, dry matter begins to accumulate. During this period, this process is slow, and by the beginning of the formation of the basket, sunflower accumulates only 15% of dry matter. By the beginning of the flowering phase, the amount of dry matter in the plant reaches 50%, and it continues to increase until the beginning of the filling of seeds, but is also spent mainly on the formation of the basket.

Physiological ripening of achenes after harvesting can be 10-50 days.

Crop rotation

Cotton-alfalfa crop rotations are widespread in cotton-growing regions. The main ones are 8-, 9- and 10-field, in which 2-3 fields are occupied by alfalfa and 5-7 fields by cotton. The share of cotton in cotton-alfalfa crop rotations accounts for 60-70%.

For cotton-alfalfa crop rotations, the designation is accepted by numbers, for example, 2:5, 2:6, 3:7, etc., the first digit in which means the number of alfalfa fields, the second – cotton.

Depending on soil conditions, the following crop rotation schemes are recommended:

  • non-saline dark typical serozems and meadow soils – 3:9, 3:7, 2:8;
  • uninhabited and slightly saline light gray soils and meadow soils – 3:7, 3:6, 2:7;
  • moderately saline gray soils and meadow soils – 3:6;
  • lands subject to severe salinization – 3:5:1, 3:6:1, where 1 denotes an reclamation field.

In the first field of cotton-alfalfa crop rotations, alfalfa is usually sown under the cover of cereal crops (barley) or together with corn, jugar or Sudanese grass for silage. In the second and third years, alfalfa grows as a single crop, and after plowing, cotton is sown, which occupies the field for 6-7 years in a row.

In diagrams 3:5:1 and 3:6:1, the last field, marked 1, is ameliorative. Before sowing alfalfa, leveling, washing, etc. are carried out on it.

Alfalfa is important as a precursor to cotton in soils subject to salinity. Due to the well-developed above-ground mass, it shades the soil surface, significantly reducing the evaporation of moisture and thereby preventing the movement of salts from the lower layers of the soil to the upper ones. When irrigated, large amounts of salt are washed into deeper horizons.

Alfalfa is also of great importance in wilt-infested fields. The causative agents of the disease do not develop on the roots of alfalfa and for the most part die without finding the substrate they need. According to the data of experimental institutions, when using cotton varieties with low resistance to wilt, their susceptibility in the first 3 years after plowing alfalfa is no more than 20-35%, while when sown on old arable land, the same varieties of cotton already in the first year are more than 90% afflicted with wilt.

Alfalfa helps to improve the physical properties of the soil, reduces subsequent water consumption for irrigation and activates the activity of soil microflora. Alfalfa of the third year of use leaves up to 15-18 t/ha of organic matter.

Other crop rotations can be used, which are developed taking into account the intensification of cotton growing and more efficient use of irrigated land. In addition to alfalfa, sorghum, corn, legumes (mung bean, peas, soybeans, sweet clover) can be good cotton precursors.

Sowing green manure crops, such as rape, mustard, vetch, peas, etc., is important for increasing soil fertility and productivity. Sowing green manure is carried out after harvesting corn or under cotton in the 4-6th year after plowing alfalfa.

The use of cotton monoculture, which is practiced in some countries, is not recommended, as this is associated with a large annual removal of nutrients from the soil and adverse mechanical effects associated with multiple irrigations and inter-row treatments. With permanent cotton crops, fertility decreases, the arable layer is sprayed, the concentration of harmful salts increases and the level of groundwater rises, the structure and phytosanitary condition of soils deteriorate.

Cotton can be grown in one place of crop rotation for 4-7 years in a row only in case of systematic fertilization, systematic control of weeds, pests and diseases.

Cotton crop rotations

Cotton occupies large areas in areas where irrigated agriculture is used, in the Central Asian and Transcaucasian countries. To increase the share of cotton in special crop rotations, repeated crops are introduced for 3-4 or more years in a row.

In the Central Asian countries, nine- and ten-field cotton-alfalfa crop rotations are used. On cultivated highly fertile soils, the following alternation schemes have been introduced:

  • 1-2 – alfalfa, 4-10 – cotton;
  • 1-2 – alfalfa, 3-6 – cotton, 7 – corn for grain, 8-10 – cotton;
  • 1 – alfalfa, 2-4 – cotton, 5 – corn for grain, 6-10 – cotton.

In these crop rotations, cotton accounts for 70, 75 and 80% of the area.

On poorly cultivated, but relatively fertile, for example, slightly and moderately saline soils, cotton crop rotations are recommended:

  • 1-2 – alfalfa, 3-6 – cotton, 7 – corn for grain, 8-10 – cotton;
  • 1-2 – alfalfa, 3-6 – cotton, corn for grain with stubble sowing of rapeseed or green manure, 8-10 – cotton;
  • 1-3 – alfalfa, 4-7 – cotton, 8 – corn for grain, 9-10 – cotton. In these crop rotations, cotton occupies 75%, 70% and 66.7%, respectively.

To improve the efficiency of cotton-alfalfa crop rotations, alfalfa crops are combined with Sudanese grass or corn, autumn and winter intermediate crops are introduced, harvested in spring for green fodder or plowed under cotton. The best intermediate crops are winter vetch, winter barley or rye, wintering peas, shabdar, mustard, rapeseed, etc.

Intermediate crops, as a rule, are used for 3-5 years of cotton cultivation, after alfalfa plowing.

It should be noted that in the countries of Central Asia, when growing cotton in a crop rotation to produce 100 kg of raw cotton, 24% less labor is spent than with permanent cultivation, fertilizers – 34% less, irrigation water – 20% less.

Fertilizer system

Cotton is one of the crops that consume a large amount of nutrients. For the formation of 100 kg of raw cotton with good development of plants, cotton consumes 5 kg of nitrogen, 1.7 kg of phosphorus and 5 kg of potassium.

Providing cotton plants with an optimal nutritional regimen can reduce the growing season by 5-10 days, increase yields and plant resistance to diseases. The lack of nutrients in the initial phases leads to a slowdown in the development of the root system, the fall of buds and ovaries. Lack of nutrition in the later phases of the growing season reduces the rate of formation of fruit branches, buds and delays flowering.

Absorption of nutrients during the growing season is uneven:

  • before budding, 3-5% of nitrogen and phosphorus are consumed from the total amount of these substances needed throughout the growing season, and 2-3% of potassium;
  • from the beginning of budding to flowering – 25-30% nitrogen and phosphorus, up to 15-20% potassium;
  • during flowering and fruit formation, which coincide with the most intensive plant growth, – 65-70% nitrogen and phosphorus, 75-80% potassium.

In the first phases of development, plants are most sensitive to phosphorus deficiency.

Intensive growing technologies involve providing cotton with an optimal nutritional regime during the growing season and increasing the efficiency of applying mineral fertilizers.

The fertilizer system includes the application of organic and mineral fertilizers. However, it should be taken into account that cotton, which is placed in the crop rotation after plowing alfalfa, makes good use of the nutrients accumulated by it and experiences less need for organic fertilizers than cotton, which is grown in fields more distant in time from alfalfa. As a rule, within 2-3 years after alfalfa, organic fertilizers are not used for cotton, but mineral fertilizers are applied.

The use of green fertilizers is important. After harvesting corn, intermediate crops can be sown, for example, peas, the green mass of which is plowed up in autumn.

The norms and methods of applying mineral fertilizers depend on the type of soil, the form of fertilizer and the placement of cotton in the crop rotation. In cotton-alfalfa crop rotations on gray soils in the first two years after plowing alfalfa, nitrogen fertilizers, as a rule, are applied in smaller quantities than phosphorus ones. The ratio of nitrogen and phosphorus in the annual norm of mineral fertilizers is 1:1.3 or 1:1.5. In subsequent years, for cotton in the same fields, the application rates of nitrogen fertilizers are increased, the ratio between nitrogen and phosphorus is set to 1 : 0.8. This ratio reduces the incidence of cotton wilt. In addition, it is favorable for cotton with an increase in nitrogen doses up to 240-300 kg/ha.

On meadow and meadow-marsh soils with a high nitrogen content, it is advisable to set the ratio N:P 1:1.5.

The norms recommended by SoyuzNIHI for applying mineral fertilizers for cotton on gray soils with a planned yield of raw cotton of 3.5-4.0 t/ha are N 270-300, P 190-210, K 120 kg/ha. In the third year after plowing alfalfa into cotton fields for autumn plowing, it is recommended to apply at least 10-15 t/ha of manure.

With industrial cultivation technology, fractional fertilization is recommended:

  • under deep plowing;
  • before sowing;
  • when sowing;
  • during the growing season.

When distributing fertilizers according to the timing of application, it is necessary to take into account the supply of nutrients to plants during the growing season. 25% of the total rate of nitrogen fertilizers should be applied before sowing and 75% – at sowing and in top dressing. With two top dressings, nitrogen is introduced in the phases of the beginning of budding and the beginning of flowering, with three, it is additionally applied in the phase of 3-4 true leaves.

At the first (early) top dressing, fertilizers are applied at a distance of 15-16 cm from the row to a depth of 12-14 cm. When top dressing in the budding phase – at a distance of 20-22 cm from the row to a depth of 3-4 cm below the bottom of the furrow. The third dressing is applied in the middle of the row spacing.

For fertilization, cultivators-plant feeders КРХ-4 are used with row spacing of 60 cm or cultivators-plant feeders КРХ-3.6 with row spacing of 90 cm.

When using increased nitrogen rates, approximately 1/3 of them are applied before sowing, the rest is used as top dressing during the budding and flowering period.

Lack of nitrogen leads to poor plant development and greater wilt damage.

Phosphorus is recommended to be applied for plowing at the rate of 60-70% of the annual norm, the rest of the amount – simultaneously with sowing and in top dressing.

A good effect is given by row application when sowing granulated superphosphate in the amount of 15-20 kg/ha P2O5. Phosphate fertilizers are added to top dressing together with nitrogen fertilizers in the cotton budding phase.

Potash fertilizers are more effective on light and non-saline soils with a high standing water table. The recommended rate is 80-100 kg/ha of K2O. Potash fertilizers are usually applied in equal proportions for plowing and top dressing, which are also carried out at the beginning of budding.

It should be borne in mind that the intensive use of nitrogen and phosphorus fertilizers increases the need for cotton in potassium nutrition. A lack of potassium leads to a violation of carbohydrate metabolism in plants, the conditions for the formation of bolls worsen, especially the outer cones of flowering, the main one becomes thinner and prone to lodging. In addition, the technological properties of the fiber are significantly reduced: metric number, strength and maturity.

According to the experimental data of SoyuzNIKhI, the most optimal ratio of nitrogen and potassium is 1:0.5. With the introduction of increased norms of nitrogen and in areas infected with wilt, the ratio shifts to 1:0.7 and even up to 1:1.

Potash fertilizers are a necessary component of fertilizer mixtures for all types of soils, except for saline ones, in which the potassium content is quite high, and with a planned raw cotton yield of more than 2.5 t/ha.

Sulfur, calcium and magnesium are important in the development of cotton.

The lack of sulfur, especially on alkaline soils, leads to stunting of plants, the leaves become yellow in color. A good result is the introduction of ammonium sulfate in the initial period of plant development.

The soils of the main cotton-growing regions of the countries of Central Asia, as a rule, contain a sufficient amount of calcium and magnesium. For these areas, the introduction of microfertilizers is effective: boron, manganese, copper, zinc, molybdenum or, accordingly, macrofertilizers enriched with these microelements. Microfertilizers are applied directly to the soil or used to soak seeds. In the latter case, the concentration of microelement salts in the soaking solution should be 0.02-0.04%, and the ratio of seeds and solution should be 2:1, soaking time should be 12 hours. basic fertilizers.

For gray soils, it is recommended to apply 0.5-1 kg/ha of a.i. boron, for meadow-marsh soils – 1.5-2 kg/ha.

Recommended norms of manganese – no more than 18 kg/ha, copper – 2-3 kg/ha, zinc – 3-4 kg/ha. Molybdenum is added as part of molybdenized superphosphate.

Tillage system

Autumn tillage for cotton depends on the predecessor.

When placing cotton after alfalfa, plowing is carried out in the second half of October with plows with skimmers to a depth of at least 28-30 cm. Before plowing, peeling is performed to a depth of 5-6 cm to cut the roots of alfalfa and prevent its growth in spring.

In fields littered with pigs (Cynodon), huma (Sorghum halepense), sytsia (Cyperus) and other rhizomatous weeds, after harvesting, guza-pai loosen the soil to a depth of 16-18 cm with plows with removed mouldboards, combing the rhizomes of weeds with mounted harrows, or chisels. Combed rhizomes are removed from the field. Before loosening, heavily dried soils are watered with a water flow rate of 600-800 m3/ha.

When placing cotton after cotton, the field is first freed from stems (guza-pai) and the irrigation furrows are leveled. Uprooting should be completed no later than the first decade of November. The uprooted stems are removed from the field. Especially thorough harvesting of goose-pai should be carried out in fields infected with wilt. In fields not charged with wilt, cotton stalks can be chopped and plowed.

When placing cotton after grain crops, after harvesting, fine stubble peeling is carried out to a depth of 5-8 cm, for better weed germination, it is recommended to carry out pre-arable watering. After the appearance of weeds, surface tillage is carried out. The optimal time for autumn plowing is August-September.

When stubble crops of annual crops are harvested, watering is done, after which deep plowing is carried out with plows with skimmers.

Two-tier plowing to a depth of 30-40 cm on fertile soils and combined plowing with soil deepening, in which a 20-25-cm soil layer is cultivated with a layer turnover, and the lower one is loosened (on saline lands with a compacted subarable horizon), have proven themselves well. In this case, when placing cotton after alfalfa, peeling is also carried out before plowing. For two-tier and combined processing, a ПД-4-35 plow is used.

Early spring and pre-sowing tillage differ depending on the state of arable land in each area. As a rule, tillage in the spring begins with two-track harrowing of the fallow in one pass of the tractor. However, in fields where leaching irrigation was carried out, harrowing in early spring may be ineffective due to the strong compaction of the topsoil. Instead of harrowing on such soils, chiselling or disking is carried out with simultaneous harrowing.

For 5-10 days or immediately before sowing on non-saline soils, harrowing is carried out with thinning. On fields clear of weeds, it can be limited to leveling the surface with the help of a planner or small, on medium and heavily weedy lands – cultivators or chisels with flat-cutting working bodies coupled with harrows and small.

Irrigations

To meet the demand of cotton for water, the soil moisture in the root layer should be more than 65-70% of lowest soil moisture capacity, which is achieved by the use of irrigation. When soil moisture is less than 65% of lowest soil moisture capacity, the yield decreases, while at moisture content above 80% of lowest soil moisture capacity, branches grow.

Irrigations are spare (moisture charging, in some cases they are also flushing) and vegetative. Spare irrigation improves the physical condition of the soil, helps remove harmful salts from the upper layers of the soil, creates a moisture reserve for the normal development of cotton, and helps reduce the number of pests.

Spare, or water-charging, irrigation in the autumn-winter period serves to accumulate moisture in the soil, ensure seed germination and the emergence of cotton seedlings. They are carried out after harvesting cotton along furrows, strips and large checks. Also, watering is carried out in the winter, before the onset of severe frosts. For these purposes, furrows are cut along which water moistens the soil. On light soils and with deep groundwater, spare irrigation is done in early spring.

The reserve irrigation rate in winter is 1000-1500 m3/ha, spring – 800-900 m3/ha. On saline soils, reserve irrigations are also leaching, the irrigation rate in this case reaches 3000 m3/ha.

In spring, to preserve moisture, harrowing is carried out in 1-2 tracks or continuous chiselling is used to a depth of 6-8 cm.

Vegetative irrigation is done during the growing season of cotton: before the flowering phase, during flowering and during the ripening period. For example, two waterings are carried out – before flowering, three or four – during flowering, and one – during the ripening period. Such distribution of irrigations is conditionally designated 2-3-1 or 2-4-1 and is called the irrigation scheme. Also, irrigation can be carried out with a decrease in soil moisture to 65-75% of lowest soil moisture capacity for a stable supply of plants with water.

The total number of vegetative irrigations, depending on the type of soil and the occurrence of groundwater, ranges from 2 to 12. Based on numerous studies, SoyuzNIHI developed approximate irrigation norms for medium-fiber cotton varieties on old arable lands.

Table. Irrigation rates for medium staple cotton varieties[2]Crop production/P.P. Vavilov, V.V. Gritsenko, V.S. Kuznetsov and others; Ed. P.P. Vavilov. – 5th ed., revised. and additional - M.: Agropromizdat, 1986. - 512 p.: ill. - (Textbook and textbooks for … Continue reading

SOIL TYPE AND GROUNDWATER DEPTH
NUMBER OF WATERINGS
IRRIGATION RATE, m3/ha
before flowering
during the flowering period
when ripe
total
Thin soils with close occurrence of pebbles and sand and deep groundwater
2-3
4-6
2-3
8-12
6000-8400
Gray soils with groundwater at a depth of 3–4 m or more
1-2
3-5
1-2
5-9
5200-7800
Gray-meadow soils with groundwater at a depth of 2–3 m
1-2
3-4
0-1
4-7
4200-6500
Meadow soils with groundwater at a depth of 1–2 m
1
2-4
0
3-5
3000-5000
Meadow-marsh soils with groundwater at a depth of up to 1 m
0
2-3
0
2-3
2000-3200

For old-arable fields with deep groundwater during furrow irrigation, the following norms are recommended.

Table. Irrigation rates for medium fiber varieties of cotton (SoyuzNIKhI)[3]Crop production/P.P. Vavilov, V.V. Gritsenko, V.S. Kuznetsov and others; Ed. P.P. Vavilov. – 5th ed., revised. and additional - M.: Agropromizdat, 1986. - 512 p.: ill. - (Textbook and textbooks for … Continue reading

SOILS (BY MECHANICAL COMPOSITION)
IRRIGATION RATES, m3/ha
before flowering
during the flowering period
when ripe
Lungs
700
750-800
650
Medium
800
900-1000
750
Heavy
900
1000-1200
850

On heavy soils, watering rates are increased, but watering is carried out less frequently.

The irrigation rate for plowed alfalfa is increased by 100-300 m3/ha.

Starting cotton irrigation too early is not recommended. With early and frequent watering, its root system develops in the upper horizons of the soil and therefore does not adequately supply water to the above-ground part of the plants during flowering and maturation. In addition, excess moisture in the early growing season contributes to the abundant development of the vegetative mass at the expense of generative organs.

However, it is important to carry out the first watering in a timely manner, as a delay can greatly delay the development of cotton plants. Depending on the condition of the soil and seedlings, the first watering is carried out 2-3 weeks after emergence. To ensure good growth of cotton, about 2-3 waterings should be carried out before flowering (by early June). Intensive watering in August and September promotes intensive growth of vegetative organs, which leads to a delay in the maturation of bolls.

The timing of irrigation is determined by the state of the plants: before flowering – by the darkening of the leaves and their slight wilting at noon, while during the flowering period – by the position of the upper flower. Properly watered cotton at the beginning of flowering has 8-9 fruit non-flowering branches above the last flower, at the end of July – 6-7 branches, at the end of August – no more than 4. However, the most objective indicator of establishing the timing of irrigation is soil moisture, which should not fall below 70% of lowest soil moisture capacity. In addition, a method has been developed for determining the timing of irrigation according to physiological indicators: the sucking power of cells and the concentration of cell sap.

Usually cotton is irrigated along the furrows. Furrows for the first irrigation are cut to a depth of 16-18 cm, for subsequent irrigation – up to 20 cm. The length of the furrows is determined depending on the permeability of the soil and the slope of the bottom of the furrow. With medium slopes (from 0.001 to 0.005) and low water permeability of the soil, furrows are made 120-150 m long, with an average – 100-120, with strong water permeability – 90-100 m. The strength of the water jet with small slopes should be up to 1-1, 2 l/s, for large – 0.1-0.3 l/s. For furrow irrigation, flexible polyethylene siphon tubes are usually used.

When using industrial technology for cultivating cotton for irrigation, instead of cutting furrows, rigid and semi-rigid polyethylene irrigation pipelines, flexible hoses, siphon tubes, machines of the ППА-165У type or sprinklers (ДДА-100М, Volzhanka, Fregat, etc.) .

When using pipelines, water is supplied to the fields through concrete trays, fixed at a certain height above the soil surface to provide water pressure. Water is taken into pipelines with the help of hydrants. The use of pipelines and sprinkler systems allows you to ration the water supply, use it economically and automate the irrigation process.

The sprinkling method allows to reduce water consumption by 2-4 times, while there is no need to cut furrows and level the field. In addition, sprinklers allow spraying of plants to control pests and diseases.

Subsoil irrigation is carried out using porous pipes or perforated hoses, which are placed at a depth of 40-50 cm in rows of 1-1.5 m. During the growing season, water pressure is maintained in them, thereby ensuring sufficient soil moisture.

The combination of furrow irrigation and sprinkler irrigation is economically more profitable than conventional furrow irrigation.

Sowing

Seed preparation

For sowing, cotton seeds with a purity of at least 97% and a germination rate of at least 85% are used.

The seeds obtained from the raw material of the first opened bolls are considered the best in terms of sowing qualities. According to the experiments carried out in Uzbekistan, the field germination of seeds of the first harvest was 94%, while the last pre-frost harvest was less than 50%. So, when sowing seeds from bolls ripened on September 4-10, 3.9 t/ha of raw cotton was obtained, and from bolls ripened on September 29 – October 9 – 2.3 t/ha.

Raw cotton for seeds at ginneries is subjected to primary processing, including ginning, linting and deletion. In addition, the preparation of seed material includes calibration, dressing and pelleting in the presence of pubescence.

Ginning is the process of completely separating the fiber from the seeds. Lintering is the process of partially separating the down from the seeds. During ginning and linting, cotton seeds can be mechanically damaged.

Delintering is the process of completely removing the down from the seed. Delintering can be mechanical, chemical (impact on the seeds of acids) and aerochemical (exposure to gaseous reagents). The aerochemical method is the most interesting, since it does not damage the seeds and does not reduce their sowing qualities. In addition, under the action of gaseous reagents, the seeds are disinfected from gommosis and other diseases, thus eliminating the need for the use of chemical means of protection.

The Research Institute of Plant Protection (Tashkent) recommends coating bare and pubescent seeds, which consists in enveloping the seeds with a mixture of nutrients, protective and stimulating substances. Dragee seeds are more free-flowing and protected from diseases and rotting in the soil.

Hairy seeds can also be used for sowing. From gommosis and root rot, they are treated with 65% feptiuram at the rate of 10-12 kg/t of seeds. Before sowing, such seeds are moistened with water in three doses (600 l/t of seeds), for which they are scattered on a cemented site with a layer of 20-30 cm, moistened and shoveled 2-3 times with an interval of 4-5 hours. Moistened seeds are collected in heaps and covered with a tarpaulin or film for languishing. At early terms of sowing in moist soil, languor is completed in 8-12 hours, at later dates in 20-24 hours.

Bare seeds are sown dry.

It is not allowed to moisten pubescent pelleted seeds.

Sowing dates

Cotton sowing is started when the soil warms up at a depth of 10 cm to 12 (13) °C and the average air temperature (12) is 13-15 °C. As a rule, in the southern regions of cotton growing, such conditions are created in the third decade of March, in the middle regions – at the end of March – early April, in the northern regions – in the second decade of April.

Too early sowing of cotton leads to a lengthening of the growing season, while too late sowing – to a delay in the opening of the boxes and a decrease in the pre-frost harvest of raw cotton.

Sowing dates are recommended to be specified taking into account soil, hydrological and weather conditions. Sowing usually begins on light, well-warmed lands of the southern slopes. The duration of sowing is not recommended to stretch.

Seeding methods

When sowing pubescent seeds, ordinary (tape) or often nested sowing methods are used. Often preference is given to the wide-row sowing method, which allows for better warming of plants, a decrease in the incidence of wilt, facilitates inter-row cultivation, irrigation, mechanized harvesting, speeds up the ripening of boxes by 4-7 days, reduces labor costs and obtains an increase in yield up to 0.3-0.5 t/ha.

With the industrial technology of growing cotton, sowing is carried out with bare seeds with the exact sowing of a given number of seeds in each nest, thus obtaining a given plant density without thinning.

In cotton growing, the row spacing is usually 60 and 90 cm with distances between nests of 10-30 (60) cm. When using the dotted sowing method, seeds are sown every 10 cm, 1-2 per nest. Such a scheme provides the most uniform distribution of plants and a given density of standing – 100-150 thousand plants per 1 ha without thinning seedlings.

A relatively new method of sowing is sowing on removed ridges (ridge method). It is carried out with the help of a bed maker or hiller, with which furrows are cut and ridges 20-30 cm high are formed. With a special device – a comber – when sowing, the top dry layer of soil is removed and the seeds are planted in loose, moist, well-heated soil. This method allows you to get early and uniform shoots.

With industrial technology, sowing is carried out by 4-row seeders СТХ-4Г, equipped with a device for applying herbicides and sowing along the ridges. Seeders СХУ-4 and СХУ-8 are also used.

Seeding rates

The sowing rate of cotton seeds depends on the row spacing, nest placement patterns, the quality of the seed material, and the conditions during the sowing period. The norm varies from 35-40 kg/ha to 70-80 kg/ha (Vavilov). According to other recommendations, the seeding rate for bare seeds is 20-25 kg/ha, for pubescent seeds – 90-100 kg/ha.

To obtain a high yield of raw cotton, the plant density should be 100-110 thousand/ha, on thin and sandy soils – up to 130-150 thousand/ha.

The seeding rate is increased by 10-15% when sowing on fields infected with wilt, as well as on saline soils.

Seeding depth

On gray soils, the sowing depth is 4-5 cm, on meadow-marsh soils – 3-4 cm.

With early sowing in moist soil, the embedment depth should be 3-4 cm, and as the soil warms up and dries, the depth is increased to 4-5 cm.

Bare seeds are recommended to be sown 1 cm smaller than pubescent ones, but always in moist soil.

Crop care

Care for cotton sowing before germination consists in destroying the soil crust with the help of light harrows or rotary hoes.

When the topsoil dries up, it is recommended to carry out recharge irrigation with a consumption rate of 600 m3/ha. For its implementation, irrigation furrows are cut during sowing.

To ensure optimal plant density, thinning is carried out no later than the phase of formation of the first (second) true leaf. Depending on the agricultural technologies used, soil fertility, varietal characteristics and sowing method, the sowing density should be in the range from 70 to 160 thousand plants per 1 ha. When using precision seeding and under optimal conditions, a given planting density can be obtained without the use of thinning.

When shoots appear, inter-row tillage is started. Depending on the purpose of each treatment, various working bodies can be used on cultivators: shaving or flat-cutting paws, hillers, rotary sprockets, etc.

The first longitudinal cultivation is carried out to a depth of 6-8 cm with simultaneous loosening of protective zones, the width of which during this period of plant development is 10-12 cm on each side of the row. The second cultivation is recommended to be done before the first vegetation watering. Subsequent cultivation – 2-3 days after each watering with some drying of the soil.

To loosen the row spacing, the extreme working bodies of the cultivators are set to a depth of 8-10 cm, the middle ones – by 12-15 cm. Starting from 2-3 cultivation, the width of the protective zones is increased to 16 cm.

The number of treatments between rows after irrigation is determined by the number of irrigations during the growing season and the onset of complete closure of cotton rows, which usually occurs in the second half of the flowering phase.

Weed control with the use of herbicides is of great importance in the care of cotton crops. Against annual weeds, a continuous pre-sowing application of treflan is used, followed by its incorporation by harrowing or disking. To apply the herbicide, sprayers of the type ОВХ-14 are used. The application rate of treflan is 4 kg/ha on light soils, 6 kg/ha on medium and heavy soils. The flow rate of the working fluid is 400 l/ha.

To control weeds in cotton rows during sowing, the herbicide Kotoran is applied in strips 20-30 cm wide at a rate of 0.8-1.75 kg/ha and a working solution flow rate of 200 l/ha. For these purposes, devices ПГС-2.45 or УГС-4 can be used, which are aggregated with cotton seeders.

The use of chemical control agents causes the death of 93-96% of weeds, accelerates the ripening of cotton and increases the collection of pre-frost raw cotton.

In the care of cotton crops, the chasing technique is important, which consists in removing the growth points of the main stem and monopodial branches. Chasing helps prevent the fall of buds and ovaries, as it creates more favorable conditions for nutrition and lighting for them. According to the experiments of SoyuzNIKhI, chasing cotton increases the yield of raw cotton up to 1.1 t/ha.

The efficiency of minting cotton depends on the duration. With too early terms of its implementation, the yield decreases. First of all, minting should be carried out from July 15 to July 25 in areas with a strong development of plants with the formation of 17-18 fruit branches on them. On medium-developed plants, chasing is carried out in the presence of 15-16 fruit branches no later than August 5. On underdeveloped plants – with the formation of 12-14 fruit branches no later than August 10 (Vavilov). According to other recommendations, minting should be carried out when 12-16 sympodial branches are formed on plants for medium-fiber varieties and 14-20 branches for fine-fiber varieties.

Chasing can be carried out using the 4ВХ-4 device, which is designed to cut the tops of cotton plants. It is hung on a tractor with a КРХ-4 cultivator.

Mechanized coinage is carried out in the second half of July – early August in two terms. The first minting begins when 40-50% of the plants have 15 or more fruit branches, the second – 7-10 days after the first. In the second pass, the tops of the plants lagging behind in growth and development are cut off. In this case, the knives of the device for chasing are set 3-5 cm higher than during the first chasing. Usually, chasing is recommended to be combined with cutting furrows for irrigation or loosening row spacings.

According to the calculations of research institutions, the costs of double mechanized chasing are 3.7 times less than those of manual chasing.

Wilt and Fusarium wilt are considered the most harmful diseases for cotton. To combat them, approved chemical plant protection products are used.

Harvest

The maturation of cotton bolls does not occur simultaneously and lasts about two (three) months (until frost). Therefore, the harvesting of raw cotton is carried out as the bolls open: with mechanized harvesting – in three steps, two of which are using cotton pickers and one – chicken harvesters; with manual cleaning – in four steps.

The vertical-spindle cotton pickers developed in the Soviet era did not allow the harvesting of raw cotton from plants with a large number of green leaves. Therefore, the technology of mechanized harvesting of such crops involves defoliation before harvesting – the treatment of cotton with chemicals to quickly fall off the leaves.

As a defoliant, spraying with magnesium chlorate is used, in the calculation for medium-staple cotton – 8-12 kg/ha, fine-staple – 13-15 kg/ha. Instead of magnesium chlorate, calcium chlorate-chloride can be used, at a rate of 20-30 kg/ha.

Relatively new preparations include Hydrel, with a recommended application rate of 6-8 kg/ha for medium staple cotton or mixed with butyl-caitax in formulations from 3+3 kg/ha to 5+5 kg/ha. UDM-type defoliants are based on magnesium chlorate mixed with nitrogen fertilizers. Spraying of crops is carried out from airplanes or helicopters, when most plants open 2 bolls in the northern regions of cotton growing, 2-3 bolls in the central regions and 4-5 bolls in the southern regions (Vavilov). According to other recommendations, defoliation is recommended when opening 3-4 bolls on medium-staple cotton plants or 4-5 on fine-staple cotton (Kolomeichenko). Falling leaves after treatment occurs on the 8-10th day.

The use of the OVKh-28 ground sprayer makes it possible to reduce the negative impact of chemicals on the environment and increase the efficiency of defoliants.

With insufficient effect from defoliation, they resort to desiccation, that is, drying plants on the vine. As desiccants, magnesium chlorate is used at the rate of 25-30 kg/ha or calcium chlorate-chloride – 45-50 kg/ha. Desiccation makes it possible to speed up the maturation of the bolls remaining after the first collections in years with adverse weather conditions, as well as to clear headlands when using a mechanized harvesting method.

For harvesting raw cotton, two-row vertical-spindle cotton pickers ХВН-1.2А can be used on crops with a row spacing of 60 cm, ХНП-1.8 – on crops with a row spacing of 90 cm, four-row cotton pickers 14ХВ-2.4А on row spacings of 60 cm. harvesting of seed raw cotton, machines for tiered collection of seed raw cotton ХВА-1.2 (60 cm) or ХВБ-1.8 (90 cm) can be used.

To collect kurak, that is, boxes that have not opened after frost, they are carried out with chicken harvesters СКО-2.4 with row spacings of 60 cm or СКО-3.6 and СКО-5.4 with row spacings of 90 cm.

Mechanized harvesting of raw cotton is carried out in fields cleared of weeds and when 75-80% of the leaves of cotton plants fall off after defoliation. The collection is carried out in three stages:

  • the first harvest – by cotton-picking spindle machines when opening no more than 50-60% of the boxes;
  • the second collection – by the same machines when opening another 20-30 (35)% of the boxes, which usually occurs 12-15 days after the first collection;
  • the third collection – chicken harvesters, which remove the remaining boxes on the bushes.

Fallen raw cotton after the first and second harvests is picked up from the ground by mechanical pick-ups ПХ-2.4 (at 60 cm row spacing) or ПХС-3.6 (at 90 cm row spacing).

Raw cotton is unloaded from the bins of cotton pickers into bulk vehicles and delivered to the procurement point. Before being sent to the procurement point, raw cotton must be dried to a moisture content of 8-12% and cleaned.

Manual harvesting of raw cotton is carried out in four (in some cases up to eight) receptions on fields clean from weeds. The first collection is started when the plant has an average of 3-4 well-opened bolls. At the second harvest, the selection of raw cotton from well-opened bolls is completed until the end of the growing season of cotton plants. When carrying out the first and second collections, the selection of unripe raw cotton from incompletely opened bolls or the collection of raw cotton in case of heavy dew in the fields is not allowed.

At the third and fourth collections, the raw cotton remaining on the bushes is sampled.

Hand-picked raw cotton, depending on the strength of the fiber, is divided into four grades.

The mechanized method of picking raw cotton compared to manual picking makes it possible to reduce labor costs by 3-4 times and to reduce the cost of raw cotton by 2 times.

Harvesting of stalks (guza-pan) of cotton after harvesting all the cotton is carried out by rooters КВ-4А and КВ-3.6А.

The use of industrial technologies, for example, at the state farm. The five-year plan of Uzbekistan made it possible to reduce labor costs to 459 man-hours per hectare, which is 2 times less than the average for other farms. The yield of raw cotton at the same time reached 4 t/ha, production costs – 11.5 man-hours/100 kg, which is 3 times less than in other farms.

Sources

Crop production / P.P. Vavilov, V.V. Gritsenko, V.S. Kuznetsov and others; Ed. P.P. Vavilov. – 5th ed., revised. and additional – M.: Agropromizdat, 1986. – 512 p.: ill. – (Textbook and textbooks for higher educational institutions).

V.V. Kolomeichenko. Crop production / Textbook. — M.: Agrobusinesscenter, 2007. — 600 p. ISBN 978-5-902792-11-6.

Fundamentals of agricultural production technology. Agriculture and crop production. Ed. V.S. Niklyaev. – M .: “Epic”, 2000. – 555 p.

Clary sage

Economic importance

The essential oil of sage is contained in its inflorescences (0.35%). It is used in perfumery, food industry and winemaking.

Cultivation areas and yield

In Russia, clary sage is grown in the Crimea and the Krasnodar Territory. From the former republics of the USSR – in Moldova.

The sown area in 1984 throughout the USSR was approximately 13 thousand hectares.

The yield of inflorescences reaches 3.0-4.0 t/ha.

Botanical description

Clary sage (Salvia sclarea L.) is a perennial herbaceous plant belonging to the Lamiaceae (Labiatae) family.

Taproot, well developed.

Stem branched, tetrahedral.

Plant height 100-120 cm.

The leaves are opposite, large, ovate, wrinkled, the edges are notched-toothed.

Inflorescence paniculate-branched, located at the ends of the branches. Corolla of flowers pink, lilac or white.

The fruit is dry, consists of four nuts with a smooth surface. Nuts contain a drying fatty oil.

Biological features

Clary sage is considered a culture that is not very demanding on heat and moisture.

Seeds begin to germinate at a temperature of 10-12 °C. Seedlings are able to withstand frosts down to -6 °C. With sufficient snow cover, it can tolerate frosts down to -30 °C.

Mature plants tolerate drought well.

Light-loving plant. Shading leads to poor plant growth, and yields are greatly reduced.

Fertile chernozem soils are considered optimal.

Vegetation and reproduction

In the first year of life, clary sage forms a rosette of basal leaves. In the second year, densely leafy stems form in the plants, inflorescences and fruits appear.

Crop rotation

In the crop rotation, special areas are allocated for sage, which are not included in the rotation and where it is cultivated for 2-3 years.

Winter crops are considered the best predecessor for spring crops. When sowing at other times, it is usually placed after mid-season spring crops.

Fertilizer system

Clary sage responds well to fertilizer application.

The recommended application rate of manure is 20 t/ha, full mineral fertilizer is N30P40-60K40.

Tillage system

When placing sage after winter crops and during spring sowing, tillage includes autumn and spring tillage.

Sowing

Sowing sage can be carried out in spring or before winter, but in such a way that its seeds do not have time to germinate before the onset of cold weather.

Usually, a wide-row sowing method is used with a row spacing of 45 cm.

According to the data of the Voznesenskaya Experimental Station of the All-Russian Research Institute of Essential Oil Crops, good results are obtained by the usual row sowing method with row spacing of 15 cm.

Seeding rate:

  • with wide-row sowing – 7 kg/ha;
  • with the usual ordinary – 12 kg / ha.

Seeding depth on cohesive soils is 2-3 cm, on loose soils – 4-5 cm.

Crop care

Care of crops of clary sage consists in harrowing by seedlings and during the growing season 3-4 inter-row tillage.

Harvest

Harvesting sage is started when the content in the inflorescences is not less than 0.12% of essential oil. To control the content of essential oil from the moment of flowering, laboratory analyzes of samples are carried out daily.

The beginning of the browning of the seeds of the lower fruits of the inflorescences is considered the optimal harvesting time.

Sources

Crop production / P.P. Vavilov, V.V. Gritsenko, V.S. Kuznetsov and others; Ed. P.P. Vavilov. – 5th ed., revised. and additional – M.: Agropromizdat, 1986. – 512 p.: ill. – (Textbook and textbooks for higher educational institutions).