Economic importance and nutritional value of tomatoes

The culture of tomatoes, due to the high nutritional value of the fruit, occupies a leading position in vegetable growing in most countries of the world.

Tomato fruits are consumed raw in the form of salads, numerous seasonings (for meat, fish and vegetable dishes), salted, pickled, stuffed.

The value of fruits as a food product is determined by the carbohydrates, organic acids, mineral salts, aromatic substances and vitamins contained in them (C, carotene, B 1, B 2 PP, K, etc.)

The varieties common in Moldova contain dry matter in fruits - 4.5 - 9.2%, sugars 1.9 - 4.9, starch - 0.05 - 0.26, fiber (with hemicelluloses) - 0.18 - 0, 42, pectin 0.12 - 0.33, nitrogenous substances - 0.55 - 1.65, organic acids - 0.30 - 0.85%, ascorbic acid - 12 - 36 mg%, carotene - 0.6 - 14 mg%, vitamin B 1 -80 mgk.

In the composition of dry matter in the fruits of tomatoes, the most carbohydrates (36 - 62%), which are represented mainly in soluble sugars among sugars - glucose and fructose. There is little sucrose in tomato fruits (0.1 - 0.5%). The content of glucose is 1.5 - 2 times more than fructose.

Pectins make up a small percentage of dry matter, but play a very important role in shaping the structure and density of fresh fruits, and the consistency of tomato processed products also depends on the bottom. Most pectins are in unripe fruits, and as the fruits ripen, their number decreases.

The group of organic acids is dominated by citric and malic acids, and also contains a small amount of tartaric, succinic, oxalic and lactic acids.

Ash elements contain a lot of potassium (38.14%), sodium (17.03%), magnesium (8.63%), phosphorus ((9.14%), calcium (6.1%), sulfur (4, 78%), silicon (4.80%), chlorine (6.93%), iron (2.33%).

The fruits of tomatoes contain a large group of vitamins (C, A, B 1, B 2, PP, etc.).

Biological features of tomatoes

Tomato is a herbaceous annual plant of the nightshade family. The stem and shoots at a young age are soft, juicy and fragile. as the stems grow, they become more springy and fall down. The plant is highly branched. The branching of the stems of a tomato is sympodial, namely: the initial shoot ends its growth with the formation of the first inflorescence, in its place the next lateral shoot protrudes, which fuses with the leaf that carries it and grows upwards with it. The first inflorescence is pushed aside.

After the formation of 1-3 leaves (depending on the variety and growing conditions), a flower brush is formed on the shoot of the first order, its growth stops and the stem continues with a side shoot of the second order, etc.

Stems rough, densely covered with glandular hairs, swollen in places of branching. The leaves are alternate, once or twice pinnately dissected, unpaired, rough. The flowers are bisexual, collected in an inflorescence - a brush with a different number of flowers in it. Calyx cleft with 5-6 lobes. Corolla cleavage, stamens 5-6 or more, filaments very short, ovary multilocular. Style straight, stigma with 2-3 or more lobes. The flowers are adapted for self-pollination, but cross-pollination by wind and insects can also occur. The fruit is a berry, juicy with different colors (red, raspberry, yellow, white).

Seeds flattened, reniform. The root of young plants is rod-shaped, but then it becomes thin and does not stand out from the rest. In addition to the main root, lateral roots appear. They grow almost horizontally.

On the lower part of the stem, after filling with moist soil, the plant is able to form adventitious roots. The depth of their penetration depends on the density, moisture and aeration of the soil, as well as on other growth factors (nutrient elements, temperature, etc.). Under good conditions, the roots penetrate the soil up to 1.0 - 1.5 m.

Zoned varieties of tomatoes and their characteristics

In the farms of Transnistria, Moldova, Ukraine, Russia and other countries of the CIS and far abroad, 40 promising tomato varieties have been released.

Breeders of the Pridnestrovian Research Institute of Agriculture made a great contribution to the development of agricultural science and bred the following varieties that are used by collective farms and farmers.

Early maturing hybrids for film greenhouses in Transnistria and Moldova: Flamenco and Corona.

Flamenco is an early hybrid. Fruit ripening 105 - 108 days after germination. The plant is powerful, medium leafy, height up to 1 m. The fruits are rounded. The color of the immature fruit is green, the mature fruit is red. Weight - 90 - 120 grams. The yield of fruits in film greenhouses is up to 13 kg / 1 m 2. recommended for unheated film greenhouses and in open ground.

Crown is an early hybrid. It differs from the FLAMENCO variety in that the fruits are flat-round in shape, weighing 150 g. used for early production of tomatoes in film greenhouses and in open ground on a trellis.

Early ripening varieties: Lyana and Juliana.

Lyana is a very early variety with uniform ripening of fruits, the duration of the period from mass shoots to the beginning of ripening when grown in seedlings is 87 - 93 days. The plant is strongly leafy and medium branched. The height of the stem is 35 - 40 cm, the diameter of the bush is 40 cm. The fruits are rounded, smooth, bright red, weight - 80 grams.

Juliana is an early variety, ripening in unison. The duration of the period from the emergence of shoots to the beginning of ripening when grown by seedlings is 102 - 104 days. The height of the main stem is 40 - 45 cm, the diameter of the bush is 35 - 40 cm. The fruits are bright red. Weight 70 - 80 grams. Designed for reusable cleaning and fresh consumption.

Large-fruited varieties: Perseus, Morning, Quiz, Torch, Potok.

Perseus is a mid-early variety: from germination to the beginning of fruit ripening 108 - 115 days. The plant is powerful, well leafy. The fruits are flat-round, large 130-180 grams, bright red. Productivity in seedling culture is from 80 to 100 tons/ha. Designed for fresh consumption of fruits, for canning, making pasta and juice.

Morning - mid-early variety: from sunrise to the beginning of fruit ripening 110 - 115 days. The fruits are round and smooth. The color of the immature fruit is light green, the mature one is red. Fruit weight 80 - 90 grams. Productivity 45 - 80 tons / ha. Intended for fresh consumption.

Quiz is a mid-early variety; in seedlings, the fruits begin to ripen 112 - 120 days after germination. The plant is medium leafy. The fruits are round, intensely red. Weight 150 -200 grams. Productivity 50 95 tons / ha. Taste qualities are good. It can be grown in seedling and seedless ways. Designed for fresh use, industrial processing.

Fakel is a mid-early variety: from germination to fruit ripening 115 - 127 days. The fruits are round, smooth, red. Weight 60 - 100 grams. Productivity 80 - 100 tons / ha. Designed for reusable cleaning, making paste, juice.

Potok is a mid-season variety: in seedling culture it begins to ripen 115-200 days after emergence. The color of the mature fruit is intense red. The fruits are round and smooth. Weight 120 - 150 grams. Fruit taste is good. yield 60 - 70 tons / ha. Differs in the increased field germination of seeds at low positive temperatures. It can be grown in seedling and seedless ways.

Orange-fruited varieties: Luch, Glory to Moldova, Alex.

Luch - an early variety: the period from mass shoots to ripening is 98 - 102 days. Fruits are oblong-oval, smooth, orange. Weight 50 -80 grams. The palatability is good, it is intended for canning, in order to obtain a dietary product for areas with increased radiation and as a prophylactic for oncological diseases.

Slava Moldavia is a mid-early variety: from germination to the beginning of maturation when grown in seedlings 109-120 days, in a non-seedling culture 95-100 days. A plant of medium foliage. The height of the main stem is 40-45 cm. The fruits are round, orange. Weight 75 - 80 grams. Productivity 50 - 60 tons / ha. It is intended for baby and diet food, for fresh consumption.

Alex is a mid-season variety: from mass shoots to the beginning of ripening when grown in seedlings, 115-120 days. Fruits are elongated oval, smooth, orange. Fruit weight 70 grams. Productivity 40 - 60 tons / ha. It is used for fresh consumption, industrial processing and production of high-quality preservatives with a high carotene content.

Long-fruited varieties: Impulse, Prize-winner, Novelty of Transnistria, Gusar, Credo, Reef, Dedication, Onyx, Maryushka, Cup of Moldova. Let's describe some of them.

Impulse - an early variety: from germination to fruit ripening in seedlings 103 - 105 days. The shape of the fruit is ellipsoid, the color is dark red. Weight 70 grams. Productivity 50 -70 tons / ha. It is used for one-time mechanized harvesting, used for seedling and non-seedling culture, for canning and fresh consumption.

Prize-winner - mid-early variety: from germination to full ripening of fruits 112-114 days. Fruits are oblong-oval. The color of the mature fruit is red. Weight 60 grams. Taste qualities are good. Productivity is 60 -90 tons/hectare. The variety is recommended to be grown in a seedless culture, suitable for combine harvesting. Designed for concentrated tomato products, salting and fresh consumption.

The novelty of Transnistria is a mid-season variety: from germination to harvest 120-125 days. Fruits are elongated-cylindrical, slightly ribbed, red. Weight 40 - 60 grams. In a seedling crop, the yield is 65 - 90 tons / ha, in a seedless crop - 50 - 60 tons / ha.

Gusar - a late variety: from sunrise to one-time harvesting 125 - 130 days. The fruits are cylindrical, smooth, the color of the mature fruit is red. Weight 75 - 80 grams. Productivity 70 - 90 tons / ha. Designed for mechanized harvesting and conservation.

Gloria is a mid-season variety: from germination to fruit ripening 115 - 120 days. The fruits are red, round-oval. Weight 80 -120 grams. Productivity 5 - 8 kg / m 2. recommended for fresh consumption and for the preparation of high-quality tomato products (tomato juice, paste, whole canning).

Varieties for protected ground: Orange, Plot, Quartet, Decembrist, Pridnestrovian.

Orange is an early hybrid: from germination to ripening in winter greenhouses, the average is 120 days. The fruit is flat-round. Weight 50 - 60 grams., The surface is slightly ribbed. The color of the immature fruit is light green, mature orange. Resistant to lack of light, heat and disease. Productivity up to 24 kg / m 2. Recommended for growing in the winter-spring crop rotation of greenhouses, as well as for growing on windows.

Pridnestrovian is a mid-early hybrid: the period from mass shoots to fruit ripening is 130 days. The fruits are round and smooth. Weight 100 -1209 grams. The color of the mature fruit is red. Designed for growing in winter and spring film greenhouses, the yield in winter greenhouses reaches 20 kg / m 2, in spring film greenhouses - 10 kg / m 2.

 2017-11-23 Igor Novitsky

You can get a good harvest of natural tomatoes, subject to the correct choice of their variety, studying the intricacies of growing seedlings or seeds, their subsequent planting, care, and the basics of pest and disease control. Knowledge of the rules of storage and compliance with optimal climatic conditions will help to save the harvest.

Tomatoes are perennial plants of the nightshade family. Originally from America, tomatoes have reliably strengthened their position among the crops grown on our plots. At the present time, tomatoes are one of the most common vegetable crops for most summer residents and large agricultural holdings.

Climate and soils

Tomato plant is thermophilic and light-loving, so tomatoes grow best on soil warmed by the sun, the need for sunlight for this crop should not be less than 8 hours. Otherwise, the tomatoes will stretch upwards, and you won’t have to hope for a good harvest.

Tomatoes grow well in well-drained soils with a pH level of 5.5 to 6.8%. The soil should be rich in organic fertilizers, nitrogen and phosphorus. If there is a problem of moisture stagnation in the area, and it is not possible to make drainage, you can plant tomato seedlings on ridges, this will to some extent solve the problem with excess moisture. When planting a tomato, it is necessary to achieve a clear distribution of water and uniform moisture over the entire surface of the soil. Otherwise, there is a possibility of problems associated with seedling infection and plant disease.

In order to create optimal conditions for the growth of seedlings or the germination of tomato seeds, it is necessary to apply organic matter in the spring, before planting and during the growing season. You can also sow green manure, a kind of fertilizer, before planting a tomato, so that the soil is saturated with nitrogen and organic matter.

Many tomato diseases live in the soil and can cause disease in other crops such as peppers, eggplant, potatoes, and other nightshade crops. In order to break the vicious circle of diseases, get rid of pathogens, you should observe crop rotation and do not plant tomatoes after corn and legumes.

What is the difference between hybrids and other varieties of tomatoes

Today, for a thousand varieties of tomatoes, there are about eight hundred hybrids. A variety is usually presented as one or a group of plants, on the one condition that these plants can be used for reproduction. Hybrids, on the other hand, are crossing between selected parent plants, during which a new type of hybrid plant will be obtained. Ordinary tomato varieties may not be as productive as hybrids, but they have excellent taste, and can also be used to produce seeds and further obtain tomatoes of this variety.

Many farmers support the method of hereditary cultivation of tomatoes on their plot, that is, they plant only those seeds that have proven themselves in the best way, and from generation to generation, gave a good harvest and were highly productive. Such varieties can be safely called family heirlooms among tomato varieties.

Hybrids, on the other hand, are tomatoes whose breeding was obtained under control, in the process of long and complex breeding work. Hybrids can be called the same tomato varieties, only with improved qualities, for example, increased resistance to diseases or a high yield threshold. In fact, if you approach the process of growing tomatoes on an industrial scale, then hybrids will greatly benefit from conventional varieties. They will give good yields, fast ripening, increased shelf life and keeping quality, as well as high quality fruits. However, hybrids have one significant drawback. Hybrid varieties lack the ability to reproduce.

If you want to plant hybrid seeds obtained from the original source, then most likely something similar to a tomato will grow, since in the second generation of plant hybrids there is a complete loss of its hybrid qualities. Also, care for tomato hybrids should be appropriate, since the plant will reveal its hybrid qualities only when appropriate care is organized for it. So if you do not have varieties of tomatoes that differ in any qualities that attract you, but you want to get a high yield of tomatoes, then the solution will be the cultivation of hybrids in your area. When buying hybrid seeds, carefully study the packaging, which will indicate what hybrid qualities the future plant will have.

Selection of seeds and seedlings

Buy tomato seeds of proven varieties. Before planting, it is better to sort them, choose the largest, regular shape, small seeds are not suitable for planting. When choosing a seed variety, start from your personal taste preferences. Before planting, it is recommended to soak the seeds in a weak solution of potassium permanganate, and then rinse with running water.

You can either grow seedlings on your own or purchase them in specialized places and greenhouses. When choosing seedlings, pay attention to the stem and foliage of the plant. The color of tomato seedlings should be uniform, light or dark in color (depending on the variety), leaves without damage, strong, elastic. Seedlings with brown or withered leaves are best not to buy. Also, special attention must be paid to the root system of the tomato. The root should be developed, uniform in color, without damage.

A plant that will bring you a good harvest in the future must be healthy, without signs of insect attack and disease infection. When growing seedlings on your own, prepare soil enriched with organic fertilizers, approximately 2:1. A container for seedlings can serve as disposable cups or small pots. Make special holes for draining excess water at the bottom of the tank and fill it with prepared soil. Then plant the seeds at a depth of no more than 2 centimeters. Maintain seedlings at a temperature not lower than +25 degrees and provide sufficient watering. A week later, with proper care, you should be pleased with the friendly shoots of tomatoes.

Planting tomatoes and fertilizing

Before planting seedlings in open ground, it is necessary to saturate the soil with organic fertilizers, nitrogen and phosphorus. The temperature suitable for the active growth of tomatoes should not be lower than +25 degrees, and the soil should warm up to +10. Otherwise, there is a risk of tomato disease with putrefactive and fungal diseases. Applying too much nitrogen to the soil will give you leaves instead of fruits, so it's important to balance your fertilizer application. Top dressing of tomatoes is best done during planting and the growing season of the plant.

To plant tomatoes, it is necessary to make indentations in the soil - holes at a distance of 35-40 centimeters from each other, the depth will depend on the length of the root system of the plant. The earth should cover the stem, to the lower leaves of the tomato. You need to plant seedlings at an angle, or lying down, in order for the root system to strengthen and begin to develop in all directions, do not worry about the tomato itself, it will stand up straight two days after planting in open ground.

If your tomatoes turn purple during the growing season, this indicates a lack of phosphorus in the soil, which will negatively affect the crop. Therefore, apply the required amount of fertilizer. Tomatoes respond well to top dressing from compost prepared from chicken manure at the rate of 300 grams per 10 liters of water.

Watering and mulching

When watering a tomato, it is necessary to direct a stream of water directly under the root of the plant, while the leaves must remain dry. The top sprinkler is not suitable for watering a tomato; plants can get sick by picking up spores of pathogens on wet leaves. Do not allow the soil to dry out, you need to establish regular watering, without stagnant water.

In areas with high temperatures, you may need to mulch around the base of the plant to keep the roots from drying out and also to help retain moisture. Mulching is fine, and if you live in cold areas, it can protect the plant from getting too cold.

Achieve optimal moisture ratios for planted tomatoes. Water for irrigation use warm or room temperature, watering is best done early in the morning or in the evening every two to three days.

Determinate and indeterminate tomato varieties

Determinate varieties of tomatoes stop their growth, with a certain number of ovaries, these varieties need to remove stepchildren. These varieties are quite suitable for open ground and begin to form their ovaries after the fifth leaf. For "lazy" farmers, there are standard varieties, they are distinguished by a strong stem and a low variety, they do not require a garter.

Differ in unlimited growth of their stem, suitable for greenhouse cultivation, varieties will bear fruit for more than a year, bringing 35 fruit clusters. Removal of stepchildren in these varieties is a necessary measure, tying is mandatory, you can tie tomatoes of these varieties to trellises.

The varieties are equally demanding on temperature, at high temperatures pollination and flowering stops, and at low temperatures below +15 degrees growth is inhibited, and fruiting is out of the question. The optimum temperature for any variety is +22, +25 degrees. Any varieties of tomatoes do not tolerate stagnant water, so the soils cultivated for this crop must have a good drainage system.

plant care

Caring for tomatoes is a rather painstaking task, however, tomatoes grown according to all the rules will delight you with an excellent harvest and excellent taste. Tomato care includes hilling, fertilizing, removing stepchildren, tying bushes, weeding, watering, spraying. Watering is carried out abundantly, three times a week. For large bushes, it is enough to shed the soil to the depth of the roots three times a week. Do not water the plants during the active solstice, as watering can damage and even lead to the death of the tomato, due to extensive burns on the plant. You should also protect a young tomato plant from sunburn for the first time two weeks after planting in open ground, for this, a fine-mesh nylon mesh is pulled over the site or the area is shaded with other materials. It is important not to deprive the plant of sunlight, but only to reduce its intensity.

When the plant reaches 40 centimeters, it is necessary to start tying up to secure the bush and prepare it for the beginning of the fruit bearing. In the tomato row, a wire is stretched, fixed every meter to pegs or reinforcement, such bushes feel quite free and give high yields. An alternative to wire can be pegs driven in next to the bush.

Leaf color defects or their irregular shape, especially in the upper part, all this is due to shifts in temperature regimes, and does not affect the taste of tomatoes in any way. The solution to the problem can be the observance of temperature regimes during landing.

Putrid lesions of non-viral etiology, can be caused by excess moisture, poor and inconsistent calcium absorption. To get rid of the problem, it is necessary to remove all rotting leaves, to establish aeration of the soil between the plants. Since an excess of moisture, due to stagnation, can completely destroy the plant.

sunburn, can also be dangerous for tomatoes. Limit scorching sunlight on extremely hot days by partial, temporary shading of the site or plants.

Cracking of tomato fruits. Tomato spoilage occurs when the plant experiences accelerated growth and excess moisture. To remedy the situation, you need to control the supply of moisture to the plant, as well as fertilize according to the schedule. Another cause of fruit cracking may be the overripeness of the tomato. Harvest your vegetables on time, this will solve the problem.

In addition to the above, many cherry tomatoes can crack at the slightest shift in temperature, and after heavy rainfall. Here, little depends on you.

No flowering on tomatoes occurs from a sudden change in weather conditions and cooling, as well as from a lack of moisture. You can resort to soil mulching if you live in an unstable climate.

Popular varieties of tomatoes

On the market today there is a great variety of varieties and hybrids that you can choose according to your personal preferences. Early-ripening varieties, as well as mid-season hybrids, which are characterized by high yields, are in great demand on the market. Below are the most popular varieties:

The hamayun hybrid is distinguished by good taste and ripening of fruits simultaneously on several brushes. The hybrid belongs to the indeterminate species.

Carlson is a tall plant, the yield is average, the taste of the fruit is wonderful. Growing tomatoes must be done on trellises, as the height of the plants is approximately 2 meters.

The lagid variety belongs to early-ripening tomatoes, the tomato fruits have a sweetish taste, have a plum-like shape, the yield is high, the height of the bush is about 50 centimeters.

White filling, this variety of tomatoes, belongs to the determinant group, the fruits have a sweet taste, round shape and bright red color. Suitable for cultivation, both in open ground and in greenhouse conditions.

Buyan, this type of tomato variety belongs to the determinant group, the bushes are medium in size, the fruits are sweet and small in size, which are great for conservation. The keeping quality of tomatoes is high.

Siberian early-ripening variety, characterized by rapid maturation, high yield, taste qualities of fruits have a moderately sweet taste, bushes of medium size with rounded tomatoes.

In addition to the varieties described above, there are also other, no less high-yielding varieties, with excellent taste. For example, such varieties as: swallow, admiral, blue leg, pink giant, swift, grain, sparkle, cherry, Nikola, shuttle, Kostroma, milady, madam, aramis and others.

Diseases of tomatoes

Late blight is a fungal, very common disease that affects almost all varieties of tomatoes, with the exception of hybrids that have resistance to it. The main reason for the occurrence and development of this disease is dampness. For preventive purposes, in the fight against this disease, spraying with milk whey of plants, as well as special broad-spectrum antifungal drugs, can act.

Macrosporiosis or brown spotting. Also a fairly common disease, it causes infection of the entire plant, starting from the lower leaves and gradually spreading. The leaves of tomatoes begin to dry, flowering stops, the fruits crumble. You can fight this disease with the help of antifungal drugs and compliance with the rules of crop rotation and the cultivation of tomatoes.

Cladosporiosis, a fungal disease that affects plants at any stage of growth. A symptom of the disease is the appearance of yellow-brown spots on the leaves, after which the leaf is covered with a continuous bloom and gradually dries out, causing the whole to die off. Prevention of this disease will consist in spraying the bushes with preparations, the active component of which will be copper. The disease is treated with antifungal drugs.

Blossom end rot is the most dangerous for tomato fruits. This disease affects the fruits of the plant. On tomatoes, brown spots first appear, caused by the reproduction of spores of the fungus. The disease is contagious, transmitted from bush to bush and can become a dangerous threat to the tomato crop. Therefore, it is so important not to leave infected fruits on the site after harvesting, as well as to identify lesions in a timely manner and exclude infection by collecting infected fruits. Blossom end rot indicates that the composition of the soil is unbalanced, an excess of nitrogen or a lack of calcium can provoke this disease. Treatment consists in examining the fruit for the presence of rot and removing them.

Tomatoes are very often infected with fungal diseases. Among them, gray rot, brown rot, black leg, root gil and others are often found. In the fight against these diseases, antifungal drugs, crop rotation, good soil aeration, balanced soil indicators, as well as the timely removal of infected plant parts will help.

Harvesting and storing tomatoes

So, in gratitude for your efforts and care, the plants will thank you with a good harvest. It is best to harvest tomatoes early in the morning or in the evening, avoiding heating them before harvesting. A ripe tomato has a bright red or yellow color (depending on the variety), a soft dense structure. Easily separated from the plant. It is better to store tomatoes in a cool, dry place, avoiding direct sunlight and close storage of vegetables.

Tomato is a heat-loving crop. Seeds begin to germinate at a temperature of 13-15, the optimum temperature for seed germination is 18-21, and for the growth and development of plants, the temperature is 22-24. at temperatures below 15, flowering stops, and at 10, plant growth stops, a prolonged decrease in temperature to 10 leads to abscission of flowers, delaying fruiting by 10-12 days. At a temperature of 0.5, flowers die, and at a temperature of -1, leaves and stems die. However, hardening of swollen seeds and seedlings increases resistance to short-term frosts to -6, at a temperature of 30, pollen in many varieties of tomato loses its viability, plant growth slows down, and stops at a temperature of 35.

Flowering of a tomato for 50-70 days after germination, the dying off of plants continues. The fruits ripen within 45-60 days. At the beginning of the ovary and fruits are green, in milky ripeness they are whitish-green, and at blange ripeness the fruits turn yellow, and then turn pink, at full ripeness they turn red.

With heavy rainfall, fruit cracking is observed. Tomato is picky about light, does not tolerate blackouts.

The soil under the tomato should be fertile, moist and loose. In relation to moisture, the tomato is demanding, especially during the period of intensive fruit growth. Lack of moisture leads to cessation of growth, abscission of flowers and ovaries. In relation to the nutrients, the tomato consumes potassium, phosphorus and sodium the most. The lack of sodium weakens the growth of the stem and leaves, phosphorus contributes to the rapid ripening of fruits, the growth of roots and early flowering. Potassium improves the tenderness of the fruit, increases the shelf life.

Temperature.

One of the main conditions for obtaining an early and good overall tomato crop is to maintain an optimal temperature regime for the plant. In different periods of growth and development, the plant requires a certain temperature of air and soil.

Tomato is a thermophilic plant. The optimum temperature for seed germination is + 24-26°C. At temperatures below + 10 ° C, they do not germinate. After the appearance of cotyledons and the first two true leaves in plants, the temperature is lowered to + 18-20 ° C during the day and + 14-15 ° C at night. This temperature regime contributes to the good development of the first inflorescence. After the appearance of the first buds on the plant, the temperature during the day is reduced to + 17-18°C, and at night it is raised to + 16°C.

The optimal air and soil temperature for a tomato is largely determined by the illumination and the content of carbon dioxide in the air. At different times of the year, the air temperature for the plant depends on the weather conditions. In sunny weather in summer - + 22-25 ° €, on a cloudy day + 20-22 ° С, at night + 16-18 ° С; in the winter and early spring months, when the illumination is very low, during the day + 17-19 ° С, and if it is very cloudy, then + 15 ° С; at night, the temperature can be reduced to +12 C. With a normal CO2 content in the air (0.03%) and normal lighting, the optimum temperature for tomato photosynthesis is within + 20-25 ° C. Under normal conditions, the air temperature above +25°C adversely affects photosynthesis. At a temperature of +30-32°C and above, a significant decrease in plant growth is observed. Pollen in such conditions becomes sterile, the flowers fall off without setting fruit. Temperatures below 14°C are also critical for fertilization. At temperatures below 10°C, plant growth stops.

Night temperature is always maintained below daytime. This is especially important during the period of fruit growth. The difference must be at least 5°C. This is necessary so that the substances assimilated by the plant during the day are not intensively consumed at night for respiration.

Soil temperature has a great influence on all life processes of a tomato plant. If it is below 14 ° C, the synthesis of substances necessary for the growth and development of buds stops in the root system. In general, it is inactive at such a temperature and cannot ensure normal growth and fruiting. The optimum soil temperature for tomatoes is +20-25°C.

In a tomato, a certain pattern can be traced in relation to temperature. The higher it is, the faster ripening occurs, the inflorescence is less branched, the fruits are smaller and have fewer chambers, the internodes are longer, etc., which ultimately leads to an early but low overall yield. On the contrary, at low temperatures, a later, but large harvest is obtained. Therefore, in relation to specific conditions, it is necessary to select the desired temperature regime of soil and air.

All varieties of tomato have different heat requirements. For example, F1 Carlson Tm C F and F1 Baby TmC prefer for their growth and development a temperature 1-2°C lower than recommended for the culture as a whole. Varieties bred in the northern regions of the country are characterized by increased cold resistance and lower heat resistance compared to varieties of southern selection. With proper hardening of seedlings, the tomato is able to withstand short-term cooling well (from +3 to 0 ° C). But even short-term negative temperatures (-0.5-1.0 ° C) have a detrimental effect on the plant.

This is one of the main factors limiting the growth and development of plants, especially in protected ground. Tomato is very picky about light. The minimum illumination at which the vegetative growth of the plant is still possible is 2-3 thousand lux. At illumination below this threshold, the decay of assimilants into respiration will exceed their income from photosynthesis.

For the formation of generative organs, buds and flowers, the illumination should be above 4-6 thousand lux. At low light intensity, the inflorescence is laid much higher than usual (above the 10-13th leaf and above), the number of leaves between the inflorescences increases. Quite often, under such lighting, a complete reduction of the inflorescence occurs. This happens when growing seedlings on short winter days, when the illumination in the middle zone of the country is 3-7 thousand lux. Inflorescences formed under such conditions have a small number of buds and flowers, which practically do not set fruits. Seedlings can be grown at this time only with artificial illumination.

The lack of light can be felt when growing seedlings for film greenhouses and open ground in the early spring months. Tomato seedlings are elongated, forming thin stems with small light leaves, which negatively affects the formation of generative organs and early harvest. At this point, everything possible must be done to prevent the negative impact of low light on the development of plants. It is necessary to ensure the maximum use of natural light. "When growing tomatoes in a greenhouse, this is facilitated by structures with the smallest possible number of ceilings in the roof, the orientation of the structure to the south, cleaning the glass from dust, and the optimal layout of plants.

Of great importance when growing seedlings is the area of ​​plant nutrition. The dense standing and shading of the stems leads to their rapid growth in height, which negatively affects the quality of the seedlings.

The optimal illumination for a tomato is 20 thousand lux or more. But with continuous illumination, the leaf blade develops poorly, chlorotic spots appear on it, plant growth is delayed. However, this is not observed under polar day conditions, which is explained by fluctuations in illumination during the day and especially in temperature. The tomato reacts weakly to the length of the day, but is very responsive to the total energy of light. The optimal length of the day for him is 14-16 hours.

Illumination and temperature largely determine the rate at which a plant passes through all stages of development. The higher the light and temperature (up to certain limits), the shorter the period before fruit ripening. At 80-100 thousand lux, the plant begins to be oppressed, burns of leaves and fruits are possible.

Tomato prefers direct solar radiation, not diffused. In the autumn-winter period, when scattered radiation predominates, or in prolonged cloudy weather, the quality of the fruits is much worse.

The ultraviolet part of the light spectrum contributes to the accumulation of vitamin C in the plant, increases its cold resistance. This must be taken into account when hardening seedlings grown under glazed frames.

A more complete use of solar radiation can be achieved by growing new varieties and hybrids of tomato that can grow and bear fruit in extreme conditions. Recommended indoor varieties, these varieties tolerate low light much better than those grown outdoors.

This is the main component of the tomato plant itself. It is included in almost all organic compounds synthesized by the leaf, dissolves and transports minerals, and helps to maintain optimal temperature conditions due to transpiration. Providing a tomato plant with water is one of the most important conditions for its normal life.

In the process of growth, the need of a plant for water is not the same. During seed germination and fruit filling, it reaches a maximum. When growing seedlings, during flowering and fruit set, soil moisture should not exceed 70-75% of the total field moisture capacity (FWC). Plants at this moment should experience a certain moisture deficit, which leads to the containment of intensive vegetative growth. At the same time, the drying of the soil, leading to shedding of flowers and even young ovaries, should not be allowed.

After fruit set on the first inflorescences, the irrigation regime of the plants is changed. It is watered more often and the soil moisture is adjusted to 75-85% of the FPV. Sharp changes in soil moisture during the period of growth and ripening of fruits are unacceptable. This causes a decrease in their average weight and may lead to cracking.

The number of irrigations depends not only on the phase of plant development, but also on solar radiation, air temperature and its movement, and agricultural technology. It is better to water tomatoes in a greenhouse and greenhouse in the morning, in sunny weather. In the open field, this can be done in the evening. Irrigation water temperature + 20-25°С. It is impossible to overmoisten the soil. This worsens its air regime and adversely affects the activity of the root system.

For a tomato plant, air humidity is of great importance, which has a tangible effect on the fertilization of a flower. Its optimal value is 60-70%. At high rates (80-90%), the pollen sticks together and stops spilling out of the pollen sacs. At low air humidity (50-60%), the pollen that has fallen on the stigma of the pistil does not germinate.

With high humidity, there is always the possibility of fungal diseases of tomato.

The gas composition of the air plays a special role in the active life of the tomato. For example, without oxygen, a plant cannot breathe. The root system is especially acute. With waterlogging of the soil, compaction, crust formation, the roots poorly absorb water and nutrients from the soil.

In the process of photosynthesis, carbon dioxide is of great importance. Its natural content in the air (0.03%) is not enough to get high yields. Its optimal content in the air for a tomato is 0.15-0.20%. In this case, with high solar radiation and a temperature that is 2-3 ° C higher than the recommended one, the maximum productivity of photosynthesis in the plant is possible. Carbon dioxide top dressing makes it possible to increase the set of fruits and increase their size, to sharply increase the overall and especially the early productivity of the crop.

Carbon dioxide top dressing is carried out from morning to 14-16 hours of the day. It is especially needed in the winter-spring months. With an excess of COa in the air at night and low illumination in winter (below 2 thousand lux), necrotic spots appear on the leaves. The movement of air contributes to a better absorption of carbon dioxide by the plant.

Ammonia has a significant effect on tomatoes. When stuffing greenhouses with fresh manure, ammonia poisoning of plants is possible - damage to the lower leaves in the form of burns. In this regard, it is recommended to plant tomatoes in greenhouses a week after stuffing.

Soil and fertilizers.

Tomato can be grown on various soils, but it feels best on sandy or loamy soils, which have good moisture capacity and breathability. In protected ground, you can use the same soil, filling it well with organic and mineral fertilizers.

It is best to place the tomato on the predecessors seasoned with organic fertilizers - on cabbage, cucumbers, etc.

In a greenhouse, it is most often planted after cucumbers, which leave excess nitrogen in the soil. In the early spring months, this leads to "fatting", i.e., excessive vegetative growth, which retards the generative development of plants. This is eliminated by preliminary introduction of nitrogen-binding materials (straw, sawdust) into the soil. The best soil acidity for tomato is 6.0-6.5. Acidic soils must be limed, otherwise many nutrients will be in a form that is indigestible for the plant.

Tomato is very responsive to the use of mineral and organic fertilizers. Most of all, it consumes potassium, especially during the fruiting period. Potassium is important in the first stages of plant development, especially with a lack of light, with the growth of fruits. It is necessary for the formation of stems and ovaries, active assimilation of carbon dioxide.

The plant uses nitrogen to form vegetative organs, especially during the period from germination to flowering. At this time, it is necessary to strictly control the doses of nitrogen nutrition, otherwise the plants begin to develop magnificently and the flowers from the lower inflorescences fall off.

The introduction of nitrogen is increased only after fruit set on the first inflorescences.

Of particular importance is the correct ratio between potassium and nitrogen during the entire period of growth and development of the tomato. In top dressing, it ranges from 2.5: 1 in winter and 1: 1 in summer.

Phosphorus consumption by the plant is low. It mainly goes to the growth of the root system, fruits and seeds. In spring, at low soil temperatures (15°C), its uptake by roots is sharply limited.

In addition to these elements, the tomato absorbs magnesium in a very large amount, which is especially necessary for it during the period of growth and ripening of the fruit. Plants also need various microelements, the richest source of which in an easily accessible form is manure.

The yield of tomatoes is determined by the diet. In order not to lose a significant part of the crop, it is best to apply mineral and organic fertilizers under it in advance, before tillage.

In this publication, I want to talk about such a vegetable crop as tomatoes, about their importance in human nutrition, morphological and biological features, as well as the conditions for growing tomatoes and caring for them.

The fruits of these plants are used fresh, pickled, pickled and in cooking. caloriesTomatoes are not high and are (150 - 200 kcal per 1 kg), their main value lies in the content of vitamins, organic acids and mineral salts. Tomato fruits contain sugars (3 - 5%), organic acids (0.4 - 0, 6%), proteins (0.6 - 1%), essential oils (0.2%), mineral salts (0.5 - 0.6%) and vitamins.

Of the refreshing organic acids, tomatoes contain citric and malic, as well as oxalic acid in the amount of 8 mg%. They are distinguished by a high content of ascorbic acid (25 - 30 mg%), carotene (1.5 - 2 mg%), lycopene (3 - 3.5 mg%). Tomato fruits also have volatile properties. All substances contained in the fruits of tomatoes play an important role in the normalization of metabolism in the human body.

At the same time, they contain the poisonous substance of plants of the nightshade family solanine in a small amount, which decreases as the fruits ripen. By the time the fruits ripen, solanine completely disappears. Therefore, you should not consume an excessive amount of fresh unripe fruits, since a dose of solanine equal to approximately 0.2 g causes headaches, fainting, sore throat and other ailments. In canned immature tomatoes, the solanine is diluted with brine to such an extent that eating tomatoes in normal quantities is not a concern.

Morphological features

They belong to the nightshade family. A perennial tomato plant is grown only as an annual, as it dies off already in mild frosts.

Propagated by seeds. Seeds are flat, kidney-shaped, silver-gray in color, pubescent. 1 g contains 250 - 350 seeds. Seeds germinate within six to eight days. Tomato seeds remain viable for about 5 to 6 years. The root system of tomatoes is well branched and reaches 1.2 - 1.5 m in diameter and 1.0 - 1.5 m in depth.

With seedling culture, the roots are distributed, mainly in the upper horizons of the soil. Adventitious roots appear on the stem almost anywhere at high humidity of air and soil.

The stalk of tomatoes is round, often decumbent, covered with glandular hairs, juicy at the beginning of development, but in the process of growth it hardens to lignification. The leaves are dissected, unpaired. Stepsons grow from the axils of the leaves - lateral shoots.

Stepchildren grow most quickly under the inflorescence. The inflorescence of tomatoes is a curl, usually called a brush. The brush can be simple (not branching), semi-complex (one branching) and complex (3 or more branches). Medium-sized yellow flowers with 5-6 petals and the same number of stamens, fused into a cone-shaped column, inside which there is a pistil. When the pollen ripens, the anthers crack from the inside and the pollen falls on the stigma of the pistil, this is how self-pollination and fruit set occur.

The tomato fruit is a berry of various shapes (spherical, flat-round, oval-round, slightly tetrahedral, irregular in shape, etc.). It can be two-, three-, four- and multi-chamber. The chambers contain seeds surrounded by a gelatinous mass.

Biological features

- a heat-loving plant that does not tolerate temperatures below 0 degrees and suffers when exposed to low positive temperatures. Seeds begin to germinate at 11 - 12 degrees.

The best temperature for germination of tomato seeds will be 22 - 26 degrees, for the process of photosynthesis 18 - 26 degrees, at 13 - 14 degrees flowering stops, and at 10 degrees and below, plant growth also stops. Long-term (more than 4 - 5 days) lowering the temperature to 6 - 8 degrees can lead to abscission of flowers. The cold hardiness of plants can be increased by hardening seeds and seedlings.

At a temperature in the region of 33 - 35 degrees, the pollen becomes sterile and no fruit formation occurs. The optimum soil temperature for tomatoes is 20 - 24 degrees, while lowering it below 15 degrees leads to a decrease in water absorption, as a result of which the plants wilt.

Tomatoes are very demanding on light and prefer direct solar radiation rather than diffused. With insufficient illumination, growth and development of plants slows down, underdeveloped flowers and sterile pollen are formed, fruits are not formed. The optimal illumination for tomatoes is in the range of 17 - 24 thousand lux.

Insufficient illumination is especially often observed when growing seedlings, seedlings begin to stretch, the stems become thin, and the quality of seedlings deteriorates. In no case should plants be allowed to stand thickly.

During the period of seed germination and fruit filling, the need of plants for water is maximum and should be 75 - 85% of the total water capacity (FWC).

During the period of growing seedlings and at the beginning of flowering, the optimal soil moisture should be 70 - 75% of the FPV. With a lack of moisture in the soil, the leaves curl and the fruits are damaged by blossom end rot.

Sharp changes in soil moisture during fruit ripening lead to massive cracking of fruits, and leaves are affected by brown spot and other diseases.

The lack of moisture during flowering leads to the fall of flowers and ovaries, and the excess moisture before flowering enhances the vegetative growth of plants to the detriment of fruit formation. The relative humidity of the air is of no small importance.

At high air humidity (above 75%), tomato plants are severely affected by diseases, in addition, pollen sticks together and does not spill out of the anthers. In the event that, on the contrary, the air humidity is very low (less than 45%), the pollen becomes sterile and also does not germinate. The optimum relative humidity for tomatoes is 50 - 65%.

Tomatoes respond well to the use of organic and mineral fertilizers. They are also characterized by a high consumption of potassium, especially during the fruiting period. In low light, the role of potassium also increases.

Classification of varieties

Depending on the nature of growth and branching, all varieties of tomatoes are divided into 3 groups:

1 - superdeterminant. They form 2-3 inflorescences on the main stem and their vegetative growth stops. Lateral shoots (stepchildren) also quickly end their growth with inflorescences. The height of the first inflorescence is 7 - 8th leaf. There is usually a single leaf between successive inflorescences on the main stem. This group includes the most early ripening varieties of tomatoes.

2 - determinant. In these varieties, 3-4 inflorescences are formed on the main stem. The height of the first inflorescence is 8 - 9 leaves. Subsequent inflorescences most often follow through 2 leaves. This group should include early and mid-early varieties of tomatoes. The beginning of maturation in these varieties occurs 5 - 7 days later than the 1st group.

3 - indeterminate (with unlimited growth). These varieties are characterized by the absence of restrictions on the growth of the main shoot, they are able to form 8 - 10 or more inflorescences. The first inflorescence is laid after the 9th - 10th leaf. This group includes late-ripening varieties.

Features of growing tomatoes (tomatoes)

They love fertile soils rich in organic matter - chernozems, dark forest, floodplain and podzolic soils. According to the mechanical composition, light loamy and heavy sandy loamy quickly warming soils.

When using sandy soils for growing tomatoes, special attention should be paid to watering in order to ensure optimal soil moisture, as well as introducing increased rates of manure or compost. On personal plots, it is almost always possible to create acceptable soil conditions for growing tomatoes.

It is difficult to tolerate prolonged stagnation of water in the soil, as this contributes to the almost complete cessation of air flow to the roots of plants. The optimal reaction of the soil environment for tomatoes is from slightly acidic to neutral.

Good predecessors for tomatoes will be cucumbers, cabbage, carrots, peas, greens (lettuce, spinach, radishes, etc.). Tomatoes should not be placed after potatoes, since these two crops are closely related and have almost the same set of diseases and pests. For the same reason, potatoes should not be placed after tomatoes. In autumn, it is advisable to plow the soil for tomatoes deeply and, if necessary, apply manure at a dose of 3 kg per 1 m 2.

With this treatment, in the spring immediately before planting tomatoes, it is necessary to loosen the soil. All these activities will contribute to the relatively rapid warming of the soil.

In the initial growing season, tomatoes poorly absorb nutrients. However, during the fruiting period, nutrient intake, especially nitrogen and potassium, increases dramatically. Despite the fact that tomatoes take out relatively little phosphorus from the soil, during the seedling period they especially need high doses of highly soluble forms of phosphorus fertilizers.

Both organic and mineral fertilizers are applied under tomatoes. Of the organic, it is most advisable to use rotted manure, humus and peat-dung composts.

The norms of organic fertilizers for tomatoes depend on the type and fertility of the soil. If manure has already been applied to the previous crop, then organic fertilizers can not be applied to tomatoes. Tomatoes respond well to mineral fertilizers, especially phosphate fertilizers. Approximate doses of nitrogen: 8 - 9, phosphorus - 9 - 10, potassium - 6 - 7 g a.i. per 1 m 2.

Growing seedlings of tomatoes

In order to grow seedlings of good quality, it is necessary to strictly observe all agricultural practices based on the biological characteristics of the tomato culture.

Seeds should have the same size and weight. To do this, they are divided by density - for 5 minutes they are dipped in a 4 - 5% solution of table salt. Lightweight seeds will rise to the surface, while the most full-weighted and completed ones will sink to the bottom.

Then the seeds will need to be washed in running water and dried. Having carried out the selection of seeds of each variety in this way, they are tied in gauze and etched in a 1% solution of potassium permanganate for 20 minutes for disinfection.

To do this, take 1 g of potassium permanganate for 1/2 cup of hot water and stir until completely dissolved. Then the seeds are dipped into the cooled solution. After 20 minutes have elapsed, the seeds will need to be rinsed with cold water under the tap. Many vegetable growers use seed hardening.

After soaking in water or fertilizer solution, the seeds are kept at a temperature of 18 - 20 degrees for 12 hours, then they are placed in the refrigerator for 12 - 16 hours, with a temperature of 0 to -1 degrees, then they are kept warm for 8 - 12 hours and so they act with variable temperatures until the seeds begin to peck (this happens after about 8-10 days).

Seeds are sown at different times, depending on the timing of planting seedlings in a permanent place. If seedlings are grown, they begin to sow for film greenhouses on March 5-10, if for temporary film shelters - on March 10-15, and when growing seedlings for open ground, you can sow from March 25 to April 5 ( for the conditions of Tatarstan).

Each variety is sown in a separate vase, cup, cup or jar, so that, as soon as shoots appear, it will be possible to move the plant to conditions with a lower temperature and good lighting.

A small hole is made in the bottom of all cups (for this purpose, for example, an awl can be used), then a nutrient mixture consisting of peat and humus (in a ratio of 1: 1) is poured into them, seeds are sown with a distance between them of 7 - 10 mm, fall asleep with the same substrate 1 cm thick and watered with warm water.

Until the shoots appear, the cups and jars are covered with plastic wrap and the temperature is maintained at about 22 - 23 degrees. When shoots appear (after about 2 - 4 days), the seedlings are placed on a window (best of all, the south or east side), where it will be cool enough and good lighting is provided. In the first: 3 - 5 days the temperature should be maintained at 14 - 16 degrees during the day, and 10 - 12 degrees at night. Then the temperature must be increased by 5 - 6 degrees. Watering seedlings should be carried out in the morning.

As soon as the cotyledon leaves take a horizontal position, and the process of formation of the first true leaf begins, they begin to pick the seedlings into pots with a diameter of about 8–10 cm. Put the pots in a box previously covered with foil and fill them with nutrient soil. For 1 bucket of peat humus mixture, add half a glass of granulated superphosphate, as well as 1.5 cups of wood ash.

Even before picking, the soil in pots is treated with potassium permanganate (at the rate of 1 g per 3-4 liters of water). When carrying out a pick, the main root of the plant is pinched by one third, and the subcotyledonous knee is buried in the soil to the level of the cotyledon leaves, trying to press the soil well against the roots. For one day, the plants are kept in the shade, and then transferred to the brightest windows.

The boxes are placed with a slope of 20 - 25 degrees towards the window; for this, a wooden bar 5 - 6 cm thick can be placed under the edge of the box. To improve the illumination of plants from the side of the room, you can put a reflective shield made of foil or a mirror. It is not necessary to water the seedlings often, but plentifully, and it is better in the morning. Three plant feedings are carried out: 1) It is carried out a week after picking for 10 liters of water (it is best to use melted snow or rain), take 0.5 matchbox of ammonium nitrate, 2 boxes of superphosphate, and 1 potassium chloride.

2) When the plant has formed from 4 to 5 true leaves, apply the same fertilizers, but increase the dose by 1.5 times. If the plants show good growth, then nitrogen fertilizers are not applied.

3) Top dressing is carried out 3-4 days before planting with phosphorus-potassium fertilizers.

About 12 - 15 days before planting, you can start hardening seedlings. In sunny weather, it is taken out to a balcony, loggia or any other protected area near the house, first for a short period of time during the day, and then for the whole day.

A few days before planting, the seedlings are left outdoors and overnight, unless frost is expected.

To avoid stretching seedlings due to insufficient illumination, 15 days before planting, they arrange it. Seedlings from one box are placed in two, the gaps are covered with sawdust or peat-humus soil. This is best done in a greenhouse or greenhouse.

At night, if frosts are expected, the seedlings are covered with thick paper, burlap and other materials.

We hope that the article Features of growing tomatoes and caring for them”was interesting to you, and you learned something new about this. If you have something to add, write in the comment section.

Tomato is a sun-demanding crop. Light is especially needed for plants grown in protected ground and varieties of southern origin. Most tomato varieties of southern origin are short-day, while northern ones are neutral to longitude of the day or long-day. With a lack of light, especially during the period of growing seedlings, the plants are strongly elongated, their development is delayed, few buds are formed. In addition, the plants bloom poorly, the flowers are poorly pollinated, the ovary falls off. The content of dry matter in fruits, the ratio of acids to sugars, the content of vitamins, etc. also depend on lighting. Therefore, plants should not be placed in shaded areas, and with a lack of light, additional illumination is carried out, which increases the productivity of plants.

Tomato is a thermophilic plant. Heat is one of the main factors and largely determines the rate of growth, ripening and yield of tomato. The optimum temperature for seed germination is 20-25°C, the minimum is 10-12°C. The most favorable conditions for plant growth are 22-24°C during the day and 16-18°C at night. At 8-10°C, the growth and maturation of pollen cease, and at 15°C, flowering stops. Temperatures above 30°C (as well as low temperatures) retard plant growth and cause bud and flower drop. Germinating seeds withstand temperatures down to -10°C until the emergence of seedlings, seedlings and young plants - minus 0.5°C, and temperatures of 1-2°C are detrimental to plants. Young plants from hardened seeds, as well as those grown without seedlings, tolerate short-term frosts down to -4°C. A night air temperature of 10-12°C increases the degree of branching of the brush, its compactness and promotes the formation of more flowers, while at a night temperature of 22-24°C fewer flowers form on the longer and thinner axes of the inflorescence. In the open ground, the tomato ripens only when the sum of positive temperatures is above 10 ° C (for the period from the first days of June to mid-August) 2150-2700 ° C and more.

Soil moisture for tomatoes is somewhat less important than heat. At the same time, large amounts of water are required to form a strong root system and above-ground biomass and obtain a rich harvest. The critical periods in water consumption are the initial period of growth and the period of formation and fruiting. Watering at this time is necessary and most effective.

The optimum soil moisture for tomatoes is 70-80% of the total field capacity. With a lack of water in the soil, the absorption of mineral nutrients by the root system worsens, the leaves lose turgor, growth processes slow down, buds and ovaries fall off, fruit filling stops, and as a result, yields decrease. Excessive soil moisture weakens the resistance of plants to diseases.

Air humidity is of great importance for the normal development of a tomato. It should not exceed 50-60% (in the first 10-12 weeks it should be within 60-65%). At a higher relative humidity, pollination of flowers worsens, they fall off, plants are more susceptible to fungal diseases (seedlings - black leg, plants and fruits - late blight), plants stretch, their yield decreases. With high air humidity and excessive nitrogen nutrition, the inflorescence can grow, i.e. leaves and even new shoots with inflorescences can grow on it. The room where tomatoes grow should be intensively ventilated.

Tomato plants are less demanding on soil than many other vegetable crops, but it is better to give them well-warmed fertile soils rich in organic matter with a pH of at least 5.5. Sandy and light loamy soils with a high content of humus and nutrients are considered the best for growing tomato crops.

The need for nutrients changes during the growing season. In the first period (before fruit formation), plants use only 5-7% of the total amount of nutrients consumed. With the growth of green mass and especially the formation and growth of fruits, the consumption of nutrients increases sharply. During this period, enhanced plant nutrition is necessary, especially in protected ground. With mineral starvation, the leaves become blue-green, then grayish, and the stems become lilac-brown. Tomatoes are very sensitive to a lack of phosphorus, especially in the initial period of growth. Almost all of the phosphorus consumed during the growing season is then used to form fruits. Nitrogen is necessary for the formation of the vegetative mass, but its excess can lead to a strong increase in green mass, that is, there is a "fatting" of plants to the detriment of fruiting. Potassium is necessary for the formation of stems and fruits of a tomato, and calcium stimulates the growth of roots and stems. Necessary for the normal growth and development of tomato plants and trace elements - magnesium, sulfur, iron, boron, manganese, copper, etc.

Under favorable conditions, tomato seeds germinate on the 3-4th day after planting (however, there are varieties, especially among the giants, in which germination occurs later - on the 5-10th day; old seeds also germinate more slowly). First, a root appears and takes root in the soil, then they leave the soil and the cotyledon leaves immediately open. The first true leaf appears after 6-10 days, the next 3-4 leaves - every 5-6 days, and then each new leaf - after 3-5 days. At the age of one month, plants usually have 4-5 leaves. The root system is especially intensively formed, which in 40-day-old plants penetrates to a depth of 80 cm and branches.

Above the 7th-9th true leaf in early ripening varieties and over the 12th-14th in late-ripening varieties, flower brushes are laid approximately 30-60 days after germination. Since that time, the process of budding and vegetative growth have been going in parallel, in most varieties without stopping almost throughout the growing season, when the plant can have leaves, stepchildren and flower clusters with buds, flowers, ovaries and fruits of various degrees of maturity at the same time.

Starting from a young age, tomato plants form lateral shoots in the axils of the leaves - stepchildren. According to the nature of growth and type of branching, 2 groups of tomato plants are distinguished (Fig. 1). In most varieties, the top of the plants, after the formation of 7-14 leaves, ends with a flower brush, and the stepson, growing from the axil of the leaf closest to the apical brush, continues the growth of the main stem (lateral or sympodial branching). After the formation of several leaves (1-6), the stepson ends its growth by laying a flower brush, and the growth of the plant continues at the expense of the nearest stepson. And so on until the end of the growing season, which usually ends with the first autumn frost. The type of bush with unlimited growth is called indeterminate (Fig. 2). In some low-growing varieties, plant growth ends with a brush, and stepchildren are formed only in the lower part of the stem. The type of bush with limited growth is called determinant (Fig. 3).

Rice. 1. Features of the growth and branching of the tomato stem: a - monopodial branching; b - removal of the leaf above the inflorescence during the growth of the first sympodium; c — sympodial branching; C - cotyledons; L - sheet; Social - inflorescence

Tomato varieties with an indeterminate type of growth are divided into 3 groups:

- early ripening weakly repaired. They are distinguished by a pronounced attenuation of growth processes during the formation of the crop on the first inflorescences, amicable early fruiting, as well as a markedly pronounced unevenness in the formation and return of the rest of the crop; the yield is quite low; the inflorescence of this group, as a rule, is simple, unbranched (there are varieties in which the first inflorescence is complex); fruit of medium weight;

- mid-season mid-repair. They are distinguished by a less pronounced attenuation of growth processes and a more uniform flow of the crop during the fruiting period; inflorescence simple or branched; fruit of medium weight;

- late-ripening strongly repaired. They have strongly pronounced growth processes, which are practically not affected by the emerging fruits of the first inflorescences; the return of the crop is uniform throughout the entire period of fruiting; inflorescences - from simple bilateral to complex.

Rice. Fig. 3. Arrangement of leaves and inflorescences on the main shoot in superdeterminate (a), determinate (b) and semideterminate (c) tomato varieties

Tomato varieties with a determinant type of growth are also divided into 3 groups:

- precocious superdeterminant. 2-3 inflorescences are formed on the main and side shoots, and the growth of the plant stops for a long time. As a result of weak repairability and limited growth of shoots by inflorescences, the plant forms a small compact bush. The second weakened wave of growth in plants is observed after the ripening of most of the fruits. The height of the first inflorescence is the 6-7th leaf. Between two subsequent inflorescences on the replacement shoots there is 1 leaf, less often - 3, and sometimes the inflorescences follow directly one after the other. The return of the harvest is very friendly, but the yield is low;

- mid-term determinant. Plants of this type are characterized by limited growth of replacement shoots after the formation of 4-6 inflorescences on them. The second wave of growth in varieties is more pronounced and occurs much earlier - after the completion of fruit formation on the first inflorescences. The height of the first inflorescence is the 8-9th leaf. Subsequent inflorescences follow through 1, more often through 2 leaves. This is the most numerous group of determinant tomato varieties used in production. Determinate varieties begin to bear fruit 5-7 days later than superdeterminant varieties, the duration of the return of the crop and the overall productivity of the varieties of this group are much higher;

- late-ripening semi-determinant. They are characterized by a weakened manifestation of determinism, i.e. prolonged absence of stem growth restriction (even after the formation of 8-10 inflorescences on it). Inflorescences are laid through 2-3 leaves. The first inflorescence is located after the 10th leaf. This is the late-ripening group of determinant tomato varieties. In terms of the uniformity of the return of the crop, it approaches late-ripening, strongly remontant tomato varieties with an indeterminate type of growth.

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And some more biology
In the process of plant ontogenesis, vegetative growth and reproductive development are determined by various morphological features, as well as environmental conditions, are in constant interaction and are inseparable. Therefore, the separation of these processes is conditional. According to D.D. Brezhnev, tomato plants in their ontogeny go through the following phases: the emergence of seedlings, the first true leaf, the growth of the above-ground mass and roots, the formation of buds, flowering, the formation and ripening of fruits.

Under favorable temperature conditions and the presence of moisture, tomato seeds germinate 3-4 days after sowing; with a lack of heat, especially when sowing in open ground - after 2-3 weeks. In the seeds, after swelling, a root first appears, then the hypocotyl knee begins to grow, which bends in the form of a loop, breaks through the soil and, as it grows, brings the cotyledons to the surface of the soil. After the seedlings straighten up and the cotyledon leaves open, further growth of the plant occurs due to the growth point of the stem.

In a tomato plant, under favorable conditions, the growth of the root system predominates in the first 2-3 weeks after germination, the cotyledon leaves increase slowly. With seedless cultivation, as well as at low temperatures in seedling structures, this period is longer. The first true leaf is formed in 6-10 days. The elevated temperature in this phase accelerates the emergence of true leaves and contributes to the extension (growth) of the hypocotyl knee, which is undesirable.

Subsequent leaves are formed after 5-6 days, and then faster - every 3-5 days. During the appearance of the 1st and 2nd true leaves, seedlings in protected ground are transplanted, which contributes to the development of a more powerful root system and seedlings of better quality. After transplantation, when the plants take root and begin to grow intensively, new leaves appear and fruiting organs (rudiments of tubercles) are laid. Buds are laid after the formation of 3-4 true leaves. At the age of one month, tomato plants have 4-5 leaves. Simultaneously with the growth of leaves, the growth of stems and roots. When a young plant forms a sufficiently developed root system, intensive growth of the above-ground mass begins. The fastest growth of seedlings is observed before planting it in the ground. After planting seedlings in open ground for 7-10 days, and with poor quality seedlings - up to 20 days, the mass of the plant does not increase (often even decreases), restoring the disturbed root system and rebuilding the physiological orientation of metabolic processes in relation to open ground. The higher the quality of the seedlings and the better the root system is preserved during planting, the shorter this period. In the future, the growth rate of a tomato plant is more dependent on the variety and growing technology.

Above the 7-9th true leaf in early-ripening varieties and over the 12-14th leaf in late-ripening varieties, about 30-40 days after germination, flower clusters are laid. Since that time, the process of bud formation and vegetative growth have been running in parallel, without stopping practically during the entire growing season and fruiting, the budding phase lasts about 15-20 days. The duration of the period from the emergence of seedlings to the beginning of flowering varies widely: in early ripening after 40-50 days, mid-ripening - 51-70, late-ripening 71-90 days. The rate of development depends on the ambient temperature. This is especially evident when growing tomatoes in open ground.

Tomato belongs to the self-pollinating plants, in one flower of which there are male and female organs. This is due to the structure of its voluminous flower. The stamens, fused with the side walls of the anthers (male organ), tightly surround the pistil (female organ), which consists of an ovary with an ovule and a style with a stigma. When the pollen matures, the stamens open from the inside and the pollen spills out on the stigma of the pistil of the same flower. This is how self-pollination occurs, which usually coincides with the opening of the bud. Further, the pollen through the style penetrates the ovary and ovule, where fertilization occurs. The ovule then develops into a seed, and the ovary develops into a fruit.
In the southern regions, in hot, dry weather, 2% of plants experience natural cross-fertilization (pollen from other flowers). In this case, pollen is carried by bees, bumblebees, thrips, ants. This is observed when the stamens with anthers develop shorter and the style with the stigma is higher than them. In this regard, in the southern regions, seed crops are isolated in open areas by 300 m and protected - by 100 m variety from variety. In woodlands and forest-steppes, this isolation can be reduced to 100 and 40 m, respectively.

Self-pollination in tomato is favored by the fact that the receptive stigma is located inside the anther cone, and the flower occupies a hanging position. Pollen of a tomato with a diameter of 21-24 microns. The fusion of the sperm with the egg occurs 35-50 hours after pollination.

Flowering begins with the first brush and goes from bottom to top. The second brush at this time is in the stage of budding and blooms only after 6-15 days. The third brush blooms about a week after the second, the fourth - a week after the third, etc. In each brush, the lower 2 flowers open first, followed by the ones sitting above them in pairs. From the beginning to the mass flowering of the brush (75% of opened flowers) takes from 2 to 6 days.

The stigma of the flower becomes susceptible to pollen almost simultaneously with the maturation of the anthers (the cracking of the latter usually occurs 24-48 hours later) and is able to receive pollen 9-12 days after the colored bud phase.

Despite the fact that the tomato self-pollinates, not every flower gives an ovary, from which a fruit would subsequently form. It depends on the conditions in which the flowering and fruiting phases take place. Under unfavorable conditions - with drought, a sharp drop in temperature - there is often a massive fall of buds and flowers. In addition, cases of mass abscission of flowers can be observed in greenhouses during the autumn-winter turnover, that is, under conditions of a shortened day.

All types of tomato (cultivated, semi-cultivated and wild) and varieties interbreed with each other very easily. For better pollination in room conditions, dry air is needed.

From the moment of fertilization, the growth of the fetus begins, and upon reaching the size characteristic of the variety, maturation begins. From the beginning of flowering to the ripening of the first fruits of early-ripening varieties, 35-45 days pass. For mid-ripening (46-65 days) and late-ripening tomato varieties, this period increases to 66-85 days. The early maturity of a tomato is determined not only by the beginning of fruit ripening, but also by the share of the crop for the first decade of fruiting and by the presence of mature fruits from the entire crop, expressed as a percentage.

In the process of fruit ripening, a whitish tint of the skin appears, the flesh becomes light green with a pale pinkish tint, the seed coat hardens (milky ripeness). Then the redness spreads to the skin and pulp of the fruit, causing a change in the outer color to brown (brown, or blanche, ripeness), and then to pink and red (pink and full, or biological, red, ripeness). At the same time, the seed chambers of the fetus are filled with cell sap, in which the seeds are immersed, the fruit becomes juicy and soft.

The duration of the growing season of tomato varieties can vary significantly depending on the weather conditions of the soil-climatic zone, growing methods and technology. This difference can reach 20-30 days. The growing season (from germination to fruit ripening) in different varieties varies greatly and is: in ultra-early varieties 85-90 days, early-ripening - 91-105, mid-early - 106-110, mid-ripening - 111-115, mid-late - 116-120, late-ripening - more than 120 days
. When growing the same variety in the south and in the north, the growing season is shorter in the first case due to better heat supply.

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