Latvian tobacco

SEEDLING CULTIVATION

Tobacco is the most common non-food agricultural crop in the world. It is grown in more than 100 countries around the world. This crop is resistant to various climatic conditions and soil types - it is grown both in tropical peaks and in mild countries such as Canada and Norway. Tobacco grows best in countries where the rate of return does not fall below zero for 120-170 days a year. To achieve the best quality indicators, tobacco needs fertile, well-moistened soils and heat. The type of soil has an impact on the size of the leaf, its texture and color. For example, on sandy soils, a tobacco leaf grows large and relatively light, with a good texture and good taste. On dense soils (muddy and clayey), tobacco leaf grows smaller, dense and with a strong aroma when burning. For different subsequent uses, you grow different varieties of tobacco. The Virginia variety is the main tobacco in the production of cigarettes, Burlinsky is used mainly as a pipe and cigarette blend. Several countries, including the United States, Turkey and Cuba, grow tobacco from the United States. The annual cycle of tobacco production begins with the planting of seeds. A tobacco seed is very small. One million seeds (enough to sow the area of a large farm) weighs only 80 g (Fig. 8). The seeds are so tender that they must be carefully protected from drying out when they begin to germinate. Seeds should be of the 1st or 2nd class with a germination rate of at least 90 and 80%, respectively, and high germination energy. Seed sowing rates per 1 m2 of the greenhouse are 0.4 g for spring sowing, 0.8 g for winter sowing; on a soil ridge - 0.5 g. For disinfection, the seeds are etched with lin: one part of 40% formalin is dissolved in 50 parts of water. The seeds are immersed in the solution for 10 minutes in bags of loose fabric. Each contains no more than 1 kg of seeds.2 liters of formalin solution are consumed per 1 kg of seeds. After mordantling, the seeds in the bag are washed with water under the tap or from a watering can for 10-15 minutes. A bag measuring about 38x24 cm is filled with 2/3 of the seme. They are tied and dipped for a day in water heated to 30 C. After that, the seeds are washed until the flowing water becomes clear. The bag is shaken to remove water and placed in a warm place, covered with damp burlap. The air temperature for germination is 27 ° C. It is desirable to change the heat regime during the day: maintain 27-30 ° C for 6 hours and 15-20 ° C for 18 hours.
In cases where several kilograms of seeds are required for sowing, they are germinated not in bags, but on trays. The tray is a rectangular frame (frame) with an internal clearance of 35x50 cm, covered on one side with dense burlap or calico, with sides 6-7 cm high. During germination, the seeds are ventilated daily, stirred, and moistened if necessary. On the 4-5th day, sprouts appear in the form of white dots, and the seed must be sown. If sowing is delayed, the seeds are dried until free-flowing or placed in a cold place (temperature 1-2 °C). Seeds can be dried only at the beginning of their germination (when white dots appear). For sowing, the seeds are thoroughly mixed with a nutrient mixture or humus passed through a sieve with small holes. The mixture is taken at the rate of 2 buckets per twenty-frame greenhouse. Before sowing, the surface of the greenhouse or wood is leveled, slightly compacted with a tamper and poured abundantly. A handful of the mixture is evenly scattered. Then the seeds are sprinkled with a layer of humus about 0.5 cm thick, compacted with a tamper and watered through a fine strainer. Greenhouses are covered with frames and mats, beds are covered with mats. Greenhouses and beds are sown in different calendar periods, depending on local conditions, in 5-6 doses with intervals in 4-5 days, in order to

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Latvian tobacco

NUTRIENT MIXTURE AND EQUIPMENT
For the establishment of greenhouses and beds, a nutrient mixture is used, on which seedlings are grown, a layer of earth for a feeding mixture, humus for sprinkling seedlings, straw or other material for an insulating layer and manure for greenhouses heated by biofuel.
The nutrient mixture is prepared from humus, soil and sand in equal parts. If there is a lack of humus, the ratio can be 1:2:1 or other. It is very important that the nutrient mixture is loose and does not form a crust on it when drying. Sand and soil should not be clayey.
The most suitable soil is from under perennial grasses, turf. Manure or forest humus should be well rotted, non-leached, loose and unpopulated. When grazing cattle on saline tracts, manure and humus can contain a significant amount of chlorine, which is harmful to seedlings.
Therefore, it is necessary to determine the chlorine content in the culture medium. If it turns out to be more than 0.08% in terms of absolutely dry weight, then such manure cannot be used. 0.11 m3 of nutrient mixture is required for 1 m2 of a heated solar greenhouse or ridge, 0.02 m3 for sprinkling the garden, that is, only 0.13 m3. For 1 m2 of the greenhouse, it is necessary to load 0.3-0.6 m3 of fresh manure.
When compacted in a pit, it will take 0.2-0.4 m3, and the volume of fresh water on the cart depends on the thickness of the heated layer. A 5 cm thick insulation layer is needed for heated and solar greenhouses. For 1 m2 of the greenhouse, 0.05 m3 of straw or other material is used - dry foxes, peat, sand.
The amount of water for watering depends on the weather and the seedlings. In order to determine the daily water consumption for a certain area, for example, for 100 m2, it is necessary to live wisely per 1 m2 (10 l) per usable area. The daily consumption will be 1000 liters, or 1 m3.
Sowing seeds and caring for seedlings is usual. To eliminate weeds, diphenamide is applied in the form of an 80% wetting powder immediately after the first sprinkling of the plant at the rate of 0.25-0.35 g of the active ingredient (a.i.) per 1 m2, diluted in 2-3 liters of water.
Seedlings turn out to be good, and their yield from 1 m2 is no less than with an annual change of the nutrient mixture. However, when seedlings are regrown, the fertility of this mixture decreases. To restore it, mineral fertilizers (nitrogen, phosphorus and potassium, which do not contain chlorine) are applied.
The benefit of the above-described technology within 5 years is substantial, since less labor and money is spent on the preparation of materials for the nutrient mixture, its preparation, loading into greenhouses and unloading.
With a longer continuous use of the nutrient mixture, its water-physical properties deteriorate, natural fertility decreases, and pathogens accumulate. Therefore, it has to be replaced with a new one.
In your nursery, depending on the size and arrangement of greenhouses and beds, there should be the following permanent equipment;
• standard-sized greenhouse frames;
• mats for insulation of greenhouses and beds;
• a screen with holes with a diameter of 1 cm for sifting materials from which the nutrient mixture is prepared, when working manually, the size of the screen should be 1x2 m;
• wire sieve for sifting powder with square meshes with a cross-section of 0.5 cm;
• watering cans with two removable strainers: with holes with a diameter of 0.5 mm for watering seedlings and with a diameter of 1 mm for watering strengthened plants;
• tubs with a capacity of 200 liters for the preparation of mineral fertilizers and pesticides;
• a tamper for easy compaction of crops in greenhouses and beds, it is a planed and sanded board 20x40 cm in size, 2 cm thick.
• supports in the form of bars with cutouts, they are placed under the short side of the raised frame;
• table and decimal scales for weighing seeds, chemicals, mineral fertilizers, etc.; • board boxes measuring 70x40x45 cm for delivering seedlings to the field;
• thermometers, shovels, rakes, forks, hoes, hand scythes, pickaxes, crowbars, stretchers, baskets, boards, hammer;
• axe, pliers, pliers, hacksaw, screwdriver, diamond for cutting glass, etc.

1 year ago | [YT] | 1

Latvian tobacco

ARRANGEMENT OF SOIL BEDS

Soil beds are prepared as follows. The allotted area is plowed in the fall. In early spring, the soil is carefully cut with a cultivator and a harrow, after which ridges with a width of 1-1.5 m and a length of about 10-15 m in the direction from east to west are cut with a bed maker. The distance between the long sides of the beds should be 70 cm. To do this, stretch the cord or place the poles in one line; after 1 or 1.5 m, the second line is marked parallel to the first. Along both lines, a furrow is drawn with a hiller, rolling the earth into the middle of the broken strip, on which the ridges will be made. In the same way, at intervals of 70 cm, beat off after blowing strips for ridges. Then transverse furrows are laid in the direction from north to south. The distances between the transverse furrows should correspond to the specified length of the ridges. After cutting the strips, the paths are cleaned, the surface of the ridges is leveled and the nutrient mixture is poured on them in an even layer 8-10 cm thick. When the frames are freed on the greenhouses, they are covered with gruds to accelerate the forcing of seedlings. The best results are when covering the beds with wooden frames with curtains made of transparent synthetic film. Each frame covers one ridge. On the beds under film frames, seedlings can be obtained in the same time frame as in solar greenhouses.

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Latvian tobacco

CONSTRUCTION OF GREENHOUSES

When growing seedlings, greenhouses of various designs are used: single-pitch with frame and film shelter and mechanized. A standard single-slope deepened greenhouse made of the same blade-concrete parts is a developed structure of a Russian log greenhouse, consisting of a pit 1, northern 4, southern 2 and end 10 parts, greenhouse frame 3, bed 5. The size of the greenhouse is determined taking into account the size and number of greenhouse frames.
With a standard size of a greenhouse frame of 160x106 cm, the tyram greenhouse has a length of 2.1 m and an outer width of 1.64 m. In a typical project, the following dimensions of the bed are adopted: length 92 cm, width 20 cm and thickness 8 cm.
At a distance of 4 cm from each end on the upper side, the bed has transverse cutouts 4 cm deep, 7 cm long at the top and 5 cm at the bottom the ends of the lateral parups. For one twenty-yard greenhouse and 10 paruznya, 11 beds are required.
The northern side is 2.12 m long, 25 cm high and 5 cm thick; A groove with a depth of 3 cm and a width of 5 cm is made along the entire length of the upper and inner side of the chamber is made with a depth of 3 cm and a width of 5 cm. For one greenhouse, 10 paruznyas are needed for the north side and 10 for the south. On the northern and southern parubinyas, the upper edge is beveled at an angle of 9°. The end paruben is 1.64 m long, 25 cm high at one end, 12 cm at the other, and 5 cm thick.
The pit can be of different sizes. The depth of the pit of warm greenhouses with bioheating should be 70 cm, the width of the lower part should be 1.38 m and the width of the upper part should be 1.5 m, for semi-warm greenhouses respectively 35 cm, 1.4 m and 1.5 m. The main advantages of greenhouses of this design are good thermal insulation and low consumption of materials for their manufacture, and the shortcomings are the labor intensity of digging a pit, the possibility of its crumbling and inconvenience of maintenance.
A ground single-slope greenhouse made of wood consists of southern and northern posts, longitudinal and transverse planks and greenhouse frames. The greenhouse is 2.2 m long and 1.64 m wide. Southern posts with a diameter of 18 cm have grooves on both sides with a length of 60 cm, a width and a depth of 5.2 cm. The posts are located at a distance of 2 m from each other. The height of the rack is 1.2 m, the installation depth is 60 cm. 11 racks are required for one greenhouse. The diameter of the server racks is 18 cm, the length of the grooves on both sides is 70, the width and depth are 5.2, the height is 130 cm. The northern posts are placed against the southern ones at a distance of 2 m. Longitudinal boards (5x20x190 cm) are placed three on the north and south sides and one (5x10x190 cm) on the north side are laid in the grooves of the posts. If there are no boards, slabs, slabs and other cheap material are used. Cross boards with a length of 154 cm are also laid in the grooves of the posts. A plank with a thickness of 2-2.5 cm and a height of 3-4 cm is sewn to the upper southern wall so that it protrudes 1.5-2 cm above the level of the greenhouse and forms a shoulder, an analogous groove in greenhouses made of reinforced concrete parts. The frames of the greenhouse are standard, glazed. A ground greenhouse is easier to maintain than a deepened one. In addition, you will spend less effort digging holes for the pillars, the walls will not crumble. But such a greenhouse is inferior to the first one in terms of thermal insulation and more materials are spent on its construction. Single-pitch greenhouses can be equipped with casings for covering with film.
There are several types of frame designs for film. The all-wood frame for the film consists of load-bearing planks 5, front and rear ends 3, in which ventilation hatches 2 are cut, closed by cover 1. In addition, the frame has side and ridge racks 7, rafter ridge bars 6.
To fix the film in the ridge bar in the upper part, two holes with a cross-section of 10x10 mm are made along the entire length. The edges of the film are inserted into them and clamped with thin glazing beads 13. Glazing beads are attached every 20-30 cm with nails. In the lower parts of the film are fixed with special reels 8. After that, they should have grooves with a cross-section of 10x10 mm along the entire length. At the same time, a shrinkage allowance of 15 cm per 1 m is made.
The film is stretched by a freely hanging reel, which should be 3-5 cm away from the surface of the inter-greenhouse passages. If the greenhouse is long, then it is advisable to make the frame in sections, and the film is attached to bobbins.
The metal frame for the film consists of transverse metal arcs 1 connected at the bottom, top and sides by longitudinal bars 2. The outer end arches at the bottom are welded with the lower longitudinal bars. The film is attached to the reels and lies freely on the covered car. At the bottom, the reels are fixed with special stops or spring clamps. Such a frame design under the film is also used for insulating beds. In Bulgaria, willow rods are used instead of steel arches.
The ends of the twigs are made along the longitudinal edges of the ridges. Greenhouses on the selected site are placed in a certain order (mainly from west to east). If there are several different types of greenhouses on your site, then they should be grouped into sections. Between the greenhouses there should be In winter, biofuel (fresh manure) is drilled in the passages between the sections of greenhouses, and in autumn, rotted manure is piled up when cleaning greenhouses. In the passages between the greenhouses, old greenhouse earth is piled.

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Latvian tobacco

BIOLOGICAL AND MORPHOLOGICAL FEATURES

Tobacco varieties
There are several basic varieties of tobacco, on the basis of which various and numerous mixtures are then prepared.
Virginia. The most common type of tobacco. It accounts for about 2/3 of the world's production of tanks. It is a vapor-processed light tobacco that is new to most cigarette and pipe tobaccos (Fig. 4, a). The name of this variety comes from the name of the former British colony "Virginia", founded by Sir Walter Reilly and named after Queen Elizabeth I of England. The main exporting countries are the United States, Brazil, India and Zimbabwe. Virginia tobacco is distinguished by its high content of sahara, which determines its pleasant taste. The nicotine content can vary from 1% to 3.5%. The average figure is 2%. It is often used as a base in any mixture, but it is perfectly smoked in its pure form. Virginia has a delicate delicate sweet aftertaste. After harvesting, the lias are dried in sheds. They stay there for about 3-5 days. After the leaves restore some moisture from the air, they are sold. Further processing is carried out by sales agents The leaves lie for 1-2 years, and then are separated from the stems. Before sale, they are sorted according to color and quality, raw materials for pipe tobacco manufacturers are obtained.
Burley. Burley is a relatively young tank. Light tobacco of natural drying (Fig. 4, b). It absorbs various flavors well, for which it is valued in pipe mixtures, and never bitter. The content of nicotine is between 1.5 and 4.5%. Burley contains almost no sugar, so the smoke from it is drier and more aromatic than from Virginia.
Burley smolders slowly and has a rich, nutty flavor. Burghley's main suppliers are Kentucky, Tennessee, Ohio, North Carolina, Virginia and Missouri (USA), as well as Mexico. Drying of tobacco leaves is carried out in large open sheds with a natural air flow, for one or two months. The color of tobacco ranges from brown to mahogany. Burley is mainly used as a supplement to Virginia.
Tobacco is a spice. Spice tobacco is not actually one type of tobacco, but rather a wide variety of special types used in small quantities to create a picant taste. The main tobacco spices are Oriental, Lata Kiya, Perique and Kentucky. Most of them are used in so-called potions. Oriental tobacco is grown in Turkey, the Balkans, and Russia. The best varieties are Izmir, Samsun, Yedidje, Cavella and Bursa. General characteristics: su hoi smoke and sometimes a slightly sour aroma. Some of these tobaccos are also used in exotic cigarettes from Egypt and other Arab countries. Latakia. The most famous tobacco is a spice (Fig. 4, c). It is named after a small Syrian port town.
Latakia tobacco grows mainly in Turkey and in the northern part of Cyprus. First, this variety is dried in the sun. After drying, the leaves are hung in closed sheds and smoked over an open flame from oak and pine wood. This treatment can last about two months. Latakia's aro mat is unique. Latakia is an indispensable component of the traditional English mixture. The content of this tobacco spice can vary from a few percent to about 40-50%. The taste is a little sharp, smoky. Dunhill's best-known tobaccos are My Mixture-965, Early Morning Pipe and London Mixture.
Perique. Peric is a very specific tobacco (Fig. 4, d). It is grown in only one place on Earth - in the parish of St. James, Louisiana in the United States. This tobacco is processed according to a secret recipe and kept in oak barrels along with plum juice, spices and fruit pulp. The result is tobacco, which, when added in small quantities to the mixture, gives it a delicate fruity aroma. The color is blue-black. This tobacco spice is produced in small quantities, so the price for it is quite high. During the agricultural season, the upper part of the plant is cut off, leaving only about 10 leaves on each: this way the remaining leaves will contain more nicotine and aromatic substances. Perique is processed in a similar way to Burghley, but for a shorter time. Then the leaves are placed under pressure, and they go through a fermentation process. This process takes at least one year. The nicotine content is overwhelming. Perik should not be smoked separately. Early Perique was used as a semi-finished product for snuff, and is now used in mixtures in very small quantities (about 5%) to give them a particularly delicate taste.
Kentucky, Kentucky tobacco borrowed its name from the American state. It is actually a specially processed Burleigh tobacco produced in Kentucky. Unlike Burley, it dries over a flame from oak, hickory or maple wood. It has a dark brown, close to black, color and a strong, rich taste. The nicotine content is quite high, so tobacco is used in limited quantities.
Dutch Drum and Samson Zware cigarette tobacco contains Kentucky. African Ken tukki is sometimes used as a spice and mixed with Virginia. Cavendish. Cavendish was originally developed by English tobacco firms. It is more of a tobacco processing method than a variety. Cavendish can be made from any type of tobacco, but mainly from Virginia and Burghley. English Cavendish is made from Virginia tobacco, it is slightly flavored and heated under high pressure on copper pans, so it is very dark. There are several English varieties of Cavendish - Dark Aromatic and Black Virginia Rattray. Tobacco is usually flavored with a liquid mixture of sugar, liquor, or whatever kind of flavors the tobacco absorbs. The purpose of this go is to produce a pleasant and smooth aroma (cherry, va-nil, chocolate, strawberry, Irish cream). Modern Cavendish is included in numerous aromatic tobaccos. Danish Cavendish is a blend of different tobacco leaves, such as Burley, Virginia, and Maryland, pressed into aged bars. Black Cavendish is a drier version of regular Burleigh Tobaccos from Tennessee and Kentucky, as well as some varieties of air-dried dark Tobaccos from Central Virginia. Such tobaccos are often flavored with various impregnations and herbs.
Oriental tobaccos (oriental). In the countries of Asia and the Mediterranean, they grow and dry in the sun the so-called oriental, or oriental, tobaccos, many of which are distinguished by a special sweetish, spicy or leafy taste and aroma (Fig. 4, f). Oriental tobaccos grow in Greece, Bulgaria, Syria, Yugoslavia, Albania, Romania, southern Russia, as well as parts of Italy, Li Wan, Iran, Iraq and Israel. A distinctive feature of this variety is the small oval leaves of a pale yellow color with a sweet aromatic taste.
Turkish tobacco. These tobaccos, despite the name, mainly grow in Greece. They have a very pleasant smell, but for various reasons they are extremely rarely used in tobacco mixtures, only in exotic ones.

1 year ago | [YT] | 1

Latvian tobacco

SETTING UP NURSERIES AND GROWING SEEDLINGS NURSERY

Growing healthy seedlings at the right time and in the right amount is an important condition for obtaining high yields of tobacco and its timely harvesting. A plot of land on which seedlings are grown in greenhouses and on beds is called a nursery.
Greenhouses in which manure and technical heat are used are called heated, and greenhouses in which solar heat is used are called solar. First of all, seedlings are sown and obtained in heated greenhouses (after 45-55 days), then in sunny and on beds (after 60 days). Usually, seedlings for 1 hectare of small-leaved and medium-leaved tobacco varieties will be provided by a greenhouse with an area of 60 m2, for gardens of large-leaved varieties, a greenhouse with an area of 40 m2 will be required.
Small-leaved tobacco varieties include Samsun, Dyubek, American, Holly, medium-leaved - Trebizond, large-leaved - Holly, Peremozhets. In biofuel greenhouses, up to 2500 seedlings are obtained from 1 m2, in solar greenhouses - up to 2000 pieces, from soil ridges - about 1500 pieces. Seedlings are planted on the site for a month. The number of greenhouses and beds depends on natural conditions.
Where the spring is early and warm, it is enough to have sunny greenhouses and ridges. In areas with a later spring, where spring frosts are possible, heated greenhouses are necessary. The plot for the nursery is allocated horizontally or with a slope of no more than 0.005 to the south or southwest.
A slope of 0.005 is a lowering of the terrain every 100 m by 50 cm. The soil should not be clayey, with a well-permeated subsoil. Areas with high groundwater standing and subject to flooding by floods or heavy rains are not suitable for growing tobacco seedlings.

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Latvian tobacco

BIOLOGICAL AND MORPHOLOGICAL FEATURES

Growth and development
The protein content in tobacco leaves grown on soils with a significant amount of humus (chernozem) is higher than in low-humus soils (gray soils, podzolics), and the carbohydrate content is inversely dependent. The aromaticity of tobacco is due to the presence of resins, essential oils and other substances.
For the growth and development of tobacco, a large amount of water is required: 500 liters for the formation of 1 kg of dry matter.
With heavy rains, improper irrigation, sometimes it is necessary to urgently (within a day) remove excess water, otherwise the plants die from a lack of oxygen in the soil. After that, the soil should be loosened in order to prevent the formation of a soil crust, which impedes the access of air to the roots.
It is important to provide tobacco with nitrogen, phosphorus and potassium elements in the right combination, the rest of the necessary elements are usually found in sufficient quantities in the soil. With a lack of assimilated nitrogen, the growth of the plant is delayed, and its productivity is low.
However, abundant nitrogen nutrition without proper combination with phosphorus and potassium leads to the formation of a large mass of leaves to the detriment of the quality of tobacco raw materials due to the high content of protein substances. Phosphorus accelerates the flowering and ripening of seeds, helps the leaves to acquire a light color and improve the commercial grade of tobacco raw materials.
With a lack of this element, the leaves have a dark green color, yellow and then brown spots appear on them, and the leaves die off. Sufficient potassium nutrition has a positive effect on the growth and development of plants, on the assimilation of carbon dioxide by leaves and the formation of carbohydrates.
With a lack of calium, the leaves darken, become wrinkled, coarse, large spots with vague outlines appear on them. Therefore, in order to obtain a high yield of good quality tobacco, it is necessary to properly cultivate the soil, remove fertilizers, taking into account the requirements of the crop, the characteristics of the soil and predecessors.
Tobacco grows well in a wide variety of soils. But they are more suitable for light, loose, sufficiently provided with basic nutrients, which allow you to create and maintain a good air and water regime. The choice of land plots for aromatic tobaccos is especially responsible. For example, the Dubek variety is best grown on red or gray soils and light chestnut soils.

1 year ago | [YT] | 0

Latvian tobacco

BIOLOGICAL FEATURES



Growth and development
Seeds are formed and ripen gradually: first in the central, then in the peripheral capsules. The ripe capsule and the seeds in it become brown, but the robot cracks. It takes 25-30 days from the beginning of fertilization to the ripening of seeds. The required average daily temperature is 20-22 C.
Seeds of peripheral capsules are lighter than central ones, and plants grown from them have elongated values and are less productive. This is one of the reasons for the heterogeneity of the shape of tobacco leaves in industrial plantings.
To obtain high-quality seeds, periphery branches and inflorescences are removed. This slightly reduces the yield of seeds, but the losses are compensated by a significant improvement in their quality.
Tobacco seeds have two phases of maturity, which are conventionally called biological and physiological.
The first occurs when the seeds are fully formed, easily separated from the receptacle, and their feeding by the mother plant has stopped. However, they are still incomplete: they germinate slowly, give unfriendly shoots. The second phase of maturity occurs about a year after harvesting, so in tobacco growing it has long been customary to use seeds of two or three years of age.
The onset of the second phase, or ripening of seeds, can be accelerated by heat treatment. Freshly harvested seeds at a temperature of 25-30 C and air humidity of 60-65% ripen within 1-2 months. Normal germination and germination energy for seeds with a moisture content not exceeding 9% is 5 years if they are kept indoors at a temperature of 15-20 °C and a relative humidity of 70%.
With less humidity, the sowing qualities are preserved even longer. It should be noted that another biological feature of tobacco seeds is that they periodically "go dormant": every year in summer, their germination rate is significantly reduced, and by autumn it is fully restored.
The chemical composition of tobacco leaves is very diverse. It is represented by more than 70 different substances, including nitrogenous, pectin, carbohydrates, resins and others. Green leaves contain 85% water. The presence of water in dried leaves depends on the variety, place of cultivation, and drying methods.
After fire drying, it is about 7%, after solar drying - 8-10%. With a moisture content of less than 12%, the leaves crumble, they have to be moistened to avoid yield loss. The moisture content of non-fermented tobacco raw materials should be 20-21%, Humidity is not allowed less than 12% or higher than 23%.
These values are approximate, since the chemical composition is very variable and depends on the growing conditions and variety. Nicotin is a nitrogenous substance produced by roots and accumulated in leaves. When smoking tobacco, a wide variety of substances are formed.
The relationship between the chemical composition of tobacco leaves and smoking qualities has not been definitively established. Therefore, the quality of tobacco products, botanical varieties, tobacco raw materials is evaluated mainly by tasting. However, the meaning of some substances has been clarified.
With an increase in the percentage of nicotine, the physiological effect (or strength) of tobacco during smoking increases. It is considered to be of medium strength with a content of 1.2-2% nicotine, strong - at 2.5%, weak - less than 1% nicotine. Potassium in the form of salts of organic acids improves the smoldering (flammability) of tobacco, and chlorine in the composition of melting compounds, on the contrary, worsens it. Protein substances have a positive effect on the smoking taste of tobacco, and carbohydrates in the form of simple sugars (fructose, glucose) have a positive effect.

1 year ago | [YT] | 0

Latvian tobacco

BIOLOGICAL FEATURES

Growth and development
Plant growth is understood as an increase in the above-ground mass and root system; Development is the qualitative changes in cells that occur from the sowing of seeds to the formation of new seeds in a certain sequence. Qualitative changes occur in the cells of the cone of growth of the stem and during cell division are transmitted to newly appearing cells, but are not transmitted to cells that were previously formed. Therefore, the upper part of the stem of an adult plant is at a higher stage of development.
As a result, inflorescences appear and leaves ripen on the suckers that emerge from the axils of the upper part of the leaves, rather than on the suckers of the lower part of the stem. Tobacco seed germination requires water and heat.
The seed absorbs water, swells and quickly germinates at a temperature of 27-28 ° C. A seedling in the form of a white dot on the seed appears on the 3-5th day. Germination of seeds that have not completed physiological maturation requires much more time. In a germinating seed, a root rudiment is first formed, and then two cotyledons.
When growing seedlings, the following phases of growth are distinguished:
• seedlings - two cotyledons appear above the ground, similar to small leaves;
• cross – two true leaves are formed, perpendicular to the cotyledons, the growth of roots is enhanced;
• ears – four leaves, slightly pressing against the stem, they are drawn to the light;
• readiness for planting – the plant has 5-6 leaves, 12-14 cm long from the root neck to the top of the last leaves, the root system is fibrous, well developed. The duration of the growth phases is quite variable, as it depends on the biological properties of the variety, on the growing conditions of the seedlings. When growing seedlings in a greenhouse, the duration of the phases is as follows:
• from sowing germinated seeds to germination - 4-6 days;
• from seedlings to the cross – 10-12;
• from the cross to the ears – 12-15;
• from ears to readiness for planting – 20-22 days.

Seedlings grow well at a soil moisture content of 60-70% of the total field moisture capacity and a temperature of 20-22 °C (it is desirable to lower it at night to 15 °C). Other necessary conditions are the provision of basic nutrients (nitrogen, phosphorus, potassium) and trace elements (boron, manganese, molybdenum, etc.), good natural lighting and ventilation.
When planting seedlings on the site, the root system is inevitably damaged, the plants fall into less favorable conditions for them. They experience transplant shock: the stem and leaves wither and droop. But then the roots begin to absorb water from the soil and extract nutrients, turgor (tissue filling with cell sap) is restored in the plant, and on the 2-3rd day after planting, the planted seedlings come to life. It begins to grow above the ground part of the plant. This phase is called stemming.
At this time, it is important to create conditions for rapid rooting and rooting of transplanted plants – to achieve minimal damage to the roots, to ensure a good soil structure on the site and sufficient application of mineral fertilizers with irrigation water.
The central flower opens first, then the inflorescences located on the branches. At this time, the growth of the stem and the formation of new leaves stops. The flowering period lasts 20-22 days. Tobacco is a self-pollinating plant. With the opening of the flower, the pollen of the stamens fully has the ability to germinate, and the eggs of the ovary are capable of fertilization.
Cross-pollination is also not possible, when pollen with higher germination energy is transferred from other flowers to insects or the wind. For fertilization, the average daily air temperature of 20-22 °C is favorable. Almost all varieties of tobacco bloom with a daylight of 15-16 hours;
There are also short-day varieties, for example, American Trebizond, Mammoth, Camel, for flowering of which a shorter daylight duration is required - 10-11 hours.
On the stem of tobacco, the leaves grow sequentially, starting from the bottom. As a result, tiering is formed: the plant has leaves of different ages and sizes. It takes 20-30 days from the beginning of leaf formation to the end of its growth, depending on the varietal characteristics and cultivation conditions. The duration of growth of lower and upper leaves is somewhat less than that of the leaves of the middle tier.
The leaves synthesize substances used by the plant to build growing organs. It takes 10-11 days from the end of the leaf growth to the beginning of its dying. Dieback is externally characterized by drying of the leaf plates, starting from the top.
The period of the greatest accumulation of produced substances is called leaf maturation. It is approximately 5 days. By this time, the dry leaf weight increases, and consequently the yield, and the aromatic properties are more fully expressed. With overripeness, the mass of dry matter decreases, the smoking properties of tobacco raw materials deteriorate - it becomes "empty", especially for tobacco grown on light soils.
Therefore, the leaves are harvested in tiers when technical maturity is reached. The growing season for annual agricultural crops is the period from the beginning of germination of sown seeds to the ripening of new ones. In tobacco, the vegetative period is considered to be the period from planting on the site to the technical maturity of the upper leaves on the stem (not on the suckers), if grown for semi-raw materials or before the ripening of seeds. The duration of the growing season depends on the variety, as well as on the growing conditions - soil, humidity, length of daylight, provision of plants with nutrients and other factors.

1 year ago | [YT] | 0

Latvian tobacco

PLANT MORPHOLOGY

Each variety of tobacco differs from the other in the shape of all or some of the plant's organs. Its external signs are more clearly expressed before flowering, when growth and development end. Traits such as plant height, leaf size, and color are variable. The shape of the leaf, the shape of the plant, the color of the flower and others, on the contrary, are quite stable and it is convenient to recognize varieties by these features. When determining the shape of the leaf, attention is paid to the shape of the blade, the base and appendages of the base of the leaf, the degree of sharpness of the top, the nature of the surface of the leaf.
Leaf blades can be of the following shape rounded — the length is almost equal to the width or slightly greater than it ; oval, or ovoid — the ratio of length to width is 1.8 or slightly less ; • oval-elongated — the ratio of length to width is 2.0, 2.1; • elliptically elongated — the ratio of length to width is not equal to 2.2-2.5 ; • elliptical — the ratio of length to width is the same as that of an oval-elongated one, but the greatest width is in the middle of the plate, and not below it ; • broadly oval — the ratio of length to width of 1.4 1.6 is less than that of the oval . The base of the leaf can be petiolate, tail, sessile, vulture. Depending on this, leaves are distinguished: • petiolate – the blade is connected to the stem by a short tail, which serves as the beginning of the midrib and can have a narrow or wide winging; • semi-petiolate – the petiole is short, weakly expressed; • sessile – no petiole ; • neck-shaped — there is no petiole, and the base of the ki plates is narrowed and elongated like the neck of a violin. At the point of attachment of the leaf to the stem, there are small lamellar appendages of the leaf base, enclosing the stem, called leaf ears. In shape, they can be elongated and rounded-oval, in relation to the stem pressed, semi-pressed, divergent, half-volume and enclosing the stem. When determining the shape of plants, the inflorescence is not taken into account. The outline of the plant is called habit. It depends on the size of the angle that is formed between the base of the leaf and the stem, the ratio of the size of the leaves of different tiers, the ratio of the length of the internodes*. If the angle of the leaves is smaller, their position is called pressed against the stem, at the angle of 45-50° – protruding, at 60-70° – raised, at 80-90° – horizontal. In the first two cases, the habit of the plant is closed - the stem is not exposed; in the other two, the habit is open, the stem is exposed. The ratio of the length of the internodes can be as follows: • the leaves are evenly distributed along the length of the stem (Du Bec); • the upper internodes are shorter than the lower ones, the leaves of the upper tiers are close together (Samsun); • the lower internodes are shorter than the upper ones, more leaves are placed on 2/3 of the stem (Trebizond). In order to imagine the shape of the plant, mentally draw a line along the edges of the leaves from the upper (excluding flowering) to the lower ones on both sides of the plant. This line defines the contour of the plant and its geometric figure. There are five forms of tobacco plants: • cylindrical — the leaves are located more or less evenly on the stem, the horizontal cross-section of the plant is approximately the same throughout the height; • oval — the largest cross-section of the plant's habit is located in its lower third; • ellipsoidal – the largest cross-section is located approximately in the middle of the stem, transverse • An internode is a section of the stem between two with gray nodes, i.e. the places where the leaf emerges.the sections in the upper and lower parts of the stem are close to each other; • cone-shaped – the largest cross-section is not in the lower part of the plant, gradually decreasing towards the upper part; • reverse cone-shaped — the largest transverse cut is located in the upper third of the plant, gradually decreasing downwards. The branches of the first and second order have paniculate flowering. About 80-90% of flowers are located on the branches of the first order. The shape of the inflorescence depends on the ratio of the length of the lower and upper branches, the density of the branches and flowers. By shape, inflorescences are spherical, shield covid, pyramidal and spreading; in terms of density, they are dense, medium, friable.

1 year ago (edited) | [YT] | 0