Cucumber is a light-loving plant. Growing cucumber in the seedling period for 15...20 days on a 10...12 hour day increases the rate of development, enhances and accelerates the formation of female flowers, and increases the early and overall yield. When daylight lengthens to 16 hours, flowering and fruiting are delayed. Bright, high-intensity light accelerates flowering, but leads to premature aging of plants and reduced yield. If there is a lack of light in the early period, the plants become stretched and the yield drops sharply.

Cucumbers are short-day plants that are successfully grown in winter greenhouses. In the summer, with a long duration of daylight hours, the flowering and fruiting of cucumbers is somewhat delayed, and the plant itself ages prematurely, which is observed in middle lane and more northern regions of Russia. Insufficient illumination in the early period of development leads to elongation and weakening of the plant.

Cucumber is very thermophilic. Its seeds begin to germinate at temperatures not lower than 15 degrees. The optimal temperature for their germination is 25...30 degrees. A prolonged cold spell, when the air temperature does not exceed 8...10 degrees, can lead to the death of plants, and at a temperature of 3...4 degrees, cucumbers die after 3...4 days.

Cucumber does not tolerate frost at all. Young shoots (in the cotyledon phase) are most sensitive to cold. In the phase of one or two true leaves, when intensive photosynthesis begins in plants, their resistance to cold increases significantly. The optimal temperature for flowering and fertilization of flowers is 18…21 degrees. The best temperature during the fruiting period is: 30...32 degrees during the day, and 20...22 degrees at night.

Cucumbers are heat-loving, so you can count on a harvest only if the optimal thermal regime is observed. A temperature of +10 degrees for 10 days will lead to disease and completely destroy the cucumber plants. The root system is sensitive to low temperatures and the whimsical nature of cucumbers is worth taking into account. Cucumbers feel very comfortable when the soil temperature in the root zone is slightly higher than above the soil. This regime is achieved, for example, by using biofuel in cucumber farming.

Cucumber is a moisture-loving plant. Cucumber is one of the most demanding vegetable crops in terms of soil and air moisture, which is due to the weak development of the root system, its low suction capacity, the large evaporating surface of the plants, and the high intensity of transpiration. With insufficient soil moisture and low relative air humidity, plants grow poorly, develop slowly, the first, most valuable ovaries fall off, few fruits are produced, they do not reach normal size, and their taste is low.

The cucumber consumes the most water during the period of maximum leaf growth and mass fruit formation. At the same time, the leaves evaporate a lot of moisture, especially in sunny weather. The optimal soil and air humidity for the growth and fruiting of cucumbers is 70...80 percent.

An increase in soil moisture to 100 percent, as well as a decrease to 60 percent, sharply reduces the fruit yield and the mass of the above-ground parts of plants. Higher soil moisture is necessary during the first growing season (before flowering) and during intensive fruit growth. During the period of mass flowering, it is possible to reduce soil moisture to 55...60 percent.

Cucumber does not tolerate watering cold water, the temperature of which is lower than the soil temperature, since in this case the root hairs easily rot and the plants die not only from the cold, but also from lack of moisture, since the poorly developed root system does not have time to supply water to the leaves, as a result of which their burns are possible. To prevent these phenomena, increase air humidity by spraying the plants and internal parts of the greenhouse with water.

Air-gas mode for cucumber. The cucumber root system responds positively to active gas exchange. Loose, well-permeable soil for air, water and heat promotes intensive growth and development of plants, increasing productivity. Cucumber needs increased levels of carbon dioxide in the air, which is a source of carbon nutrition. As a rule, the concentration of carbon dioxide in the air is 0.03 percent, but increasing it by 5...10 times in protected soil significantly increases the productivity of the crop.

Cucumber is demanding on the structure and fertility of the soil. It is characterized by rapid growth and development. Cucumber produces a harvest in a relatively short time, while consuming a lot of nutrients. That is why cucumber is grown on highly fertile soils and frequent fertilizing with small doses of fertilizers is carried out. However, cucumber is not resistant to salinity and is also very sensitive to high concentrations of soil solution and soil acidity. The optimal reaction of the soil environment (pH) for cucumber is 6.2...6.8. Excess nitrogen nutrition enhances the growth of leaves and shoots, but reduces the number of female flowers.

Cucumbers are an annual herbaceous plant of the Cucurbitaceae family. According to many scientists, they come from the humid tropical zone of India or Indochina.

The root system of cucumbers consists of taproot and side branches. Cucumbers have the ability to form additional roots. The stem of the plant is erect when young, but after flowering it is creeping and branching. The main stem forms side shoots - first-order lashes, from which second-order lashes extend, etc. The length of the lashes and their number on the plant depends on the variety and growing conditions. U early varieties the lashes are short (50-80 cm), in late-ripening ones they are longer, they have more lateral branches, the length of the main stem reaches 2.5 m or more.

The leaves are petiolate with a three- or five-lobed blade, located alternately on the cucumber vines. The leaf that appears first on the plant differs in blade shape from the rest. Each subsequent leaf is more dissected and jagged. The size and color of the leaves depends on the varietal characteristics and growing conditions.

Cucumber is in most cases a monoecious dioecious plant, which produces male and female flowers (Fig. 1). Male ones are located in the axils of the leaves in the form of inflorescences (scutes). Female flowers are usually formed in other nodes one at a time, less often two or three. Male flowers have stamens containing pollen, female flowers have an ovary located below the corolla and stigma, sitting inside the flower. The number of male flowers on a plant significantly exceeds the number of female ones. However, there are forms of cucumbers with hermaphroditic (bisexual) flowers. In parthenocarpic forms, fruits are formed without pollination of flowers.

Recently, at the Crimean and Maikop experimental stations of the All-Union Institute of Plant Growing named after. N.I. Vavilova created gynocyous (partially dioecious) varieties: plants produce only female flowers, while others produce male and female flowers.

Cucumber is a cross-pollinating plant. The pollen is sticky, glued into lumps, and is not carried by the wind. Pollination occurs only with the participation of insects - bees, bumblebees, wasps, flies, thrips, ants, butterflies.

Rice. 1. Cucumber flowers:
a - male; b - female; c - hermaphroditic.

The fruit of cucumbers is a false berry from 5 to 70 cm long. It has from 3 to 5 seed chambers. The fruits are eaten in an unripe state, ranging from 3-5-day-old ovaries to greens at the age of 8-12 days. The most important morphological characteristics of the fruit are its shape, size, color, surface and pubescence.

The pubescence can be simple (each individual spine consists of a hair) and complex (the hair has a thickened spherical base). The surface of the fruit can be smooth, finely tuberculate or coarsely tuberculate. With simple pubescence, the surface of the fruit is smooth, with complex pubescence, it is tuberous. Based on the color of the fruit pubescence, cucumber varieties are divided into black-thorn and white-thorn; there are significant differences between black-thorn and white-thorn cucumbers. Fruits with black pubescence are very fragrant, tasty both fresh and salted, their skin is soft. But they can turn yellow while still on the plant and quickly lose their presentation. White-thorned varieties are less tasty and their skin is rougher. However, they retain their green color for a long time and also have a good presentation.

The bitterness of cucumbers is due to the substance they contain, cucurbitacin. Under unfavorable conditions (lack of moisture, light, food, low or too high temperatures in dry sunny weather), the development of fruits is delayed, and in most cases they are bitter.

The shape of cucumber seeds is elongated-elliptical, their length is 7-16 mm, width - 3-6, thickness 2-3 mm. Weight of 1000 seeds - 16-33 g.

Cucumber shoots, depending on weather conditions, appear 3-10 days after sowing. When seeds germinate, two thick, fleshy cotyledons appear on the soil surface, which serve as leaves, feeding all the organs of the young plant. Their importance in the life of a plant is great: the growth and timing of the beginning of flowering of cucumbers depend on them. Under favorable conditions, the first true leaf appears 5-6 days after germination. During its formation, flower tubercles begin to form in the axil. The next leaves are formed at intervals of 2 to 7 days. When 5 leaves appear, the plant begins to branch and soon blooms. Biological (seed) ripeness of the fruit occurs 40-69 days after flowering.

Attitude to heat. Cucumbers are very demanding of heat. Seeds begin to germinate at a temperature of 12-15°. After special hardening, the temperature minimum for enzymatic processes decreases; seeds can germinate at 10°C. The higher the temperature, the faster and more friendly the seedlings appear. At 20°, seedlings appear after 5 days, at 18° - after 10. When sowing seeds in soil with a low temperature, seedlings are significantly delayed or die completely. Therefore, cucumbers open ground it is necessary to sow when the soil at a depth of 10 cm warms up to 12-14°.

A decrease in temperature below 15° negatively affects the absorption of water and nutrients from the soil solution by the roots and disrupts the normal functioning of the leaves of adult plants. When the soil temperature drops to 8-9°, the root system functions poorly. If the temperature remains below 10° for a long time, the plants stop growing and may die. Short-term frosts are also detrimental to plants.

Cucumber plants are especially demanding of temperature during the first period of growth and development, as well as in the flowering and fruit formation phases. At temperatures above 20°, plants bloom after 26 days, and below 20°, after 37 days after germination. The optimal temperature for cucumbers is 25-30° during the day and 17-18° at night. Before the onset of economic ripeness of cucumbers, the sum of average daily active (? 15°) air temperatures is 800-1000°; for the ripening of the seeds - at least 1500°.

Attitude to moisture. Cucumbers are very demanding on soil and air moisture. According to long-term data from BelNIIKPO, with a harvest of 200-300 c/ha, plants consume 10-15 m 3 of water per 1 c of production. This is explained by the fact that they develop a large vegetative mass; the leaf surface evaporates a lot of moisture. In addition, the root system of cucumbers has a low suction force (1.5-2 atm) and is located mainly in the upper layer of soil (at a depth of 20 cm), where moisture reserves are unstable. Therefore, if there is a lack of moisture in the soil, the leaves begin to wither, the plants grow slower, and their productivity decreases.

The most favorable relative air humidity for cucumbers is 80-90% (in greenhouse conditions - up to 100%), soil - 70-80% of the lowest moisture capacity (MC). Excess soil moisture exceeding 85% of total moisture capacity, especially in combination with low temperatures, is harmful to cucumbers.

Attitude to light. Cucumbers are light-loving plants, although they are less demanding of light than of heat and moisture. Varieties of cucumbers have significant differences in their light requirements. For most varieties, growing under shortened daylight hours increases yield; for some, ripening is accelerated. These features are very important when cultivating cucumbers in protected soil. When shaded, they grow and bear fruit poorly. The minimum illumination at which flowering and fruiting of cucumbers is possible is 2400 lux. Optimal illumination - 20 thousand lux.

One of the important biological features of cucumbers is that in most of the most common varieties, about 80% of the female flowers (with ovaries) are located on the side shoots (lashes), and the male flowers are located on the main shoot (stem). When the plants in the rows are dense, mainly the main shoot develops with male “barren flowers”, the side shoots grow weakly, which negatively affects the yield. Therefore, you should not thicken the cucumber crops. When growing them in a garden bed, the illumination of plants is regulated mainly by their placement on the area and the direction of sowing in relation to the cardinal points.

Requirements for food conditions. Cucumbers have a relatively high nutrient intake compared to other vegetable crops. The data obtained in the experiments of BelNIIKPO showed that the consumption of basic nutrients from the soil by cucumbers per 100 centners of commercial products is 11 kg of nitrogen, 6 kg of phosphorus and 24 kg of potassium.

Cucumber plants differ from other vegetable crops in their high demands on soil nutrition conditions, which is quite consistent with the growth and development rates of this crop. In a relatively short growing season (90-105 days), under favorable conditions, they form a fairly high yield of fruits. Moreover, their root system is located mainly in the arable horizon and cannot use nutrients from deeper layers of the soil. Therefore, cucumbers should be placed on highly fertile soils rich in essential nutrients.

The most favorable amount of humus in soils for cucumbers is 2-4%. Cucumbers do not tolerate acidic soils and high concentrations of soil solution, especially when they are young. The optimal reaction of the soil solution is close to 6-6.5 pH, and the permissible one does not go beyond 4-7.6 pH. The largest number of female flowers is formed when cucumbers are placed on soil whose reaction is close to neutral (pH 5.9-6.1). The degree of saturation with bases must be at least 75-80%. The content of mobile aluminum is not allowed to exceed 3-4 mg per 100 g of soil. Cucumbers have low salt tolerance compared to other vegetable crops.

The need of plants for basic nutrients changes during their growth and development. At the beginning of the growing season, cucumber plants absorb nitrogen more intensively. With the growth of lateral vines, the absorption of potassium and phosphorus increases, then, due to the strong increase in vegetative mass, nitrogen consumption increases again.

Air-gas regime. Cucumber seeds are very sensitive to lack of air; under these conditions, germination energy and often germination are sharply reduced. This is one of the reasons for the high responsiveness of cucumbers to light and loose soils.

Cucumber plants are very responsive to increased carbon dioxide in the air. It has been established that the application of fresh manure provides not only root nutrition for cucumbers, but also air supply. Feeding cucumber plants with carbon dioxide increases their resistance to diseases and pests. An increase in the concentration of ammonia, which is released during the decomposition of organic matter, above 0.6% causes leaf burns, and at 4% the plants die.

To provide the roots of the plant with oxygen, frequent loosening of the soil is necessary, thanks to which the soil reserves are replenished from the air.

Cucumber appeared in culture more than 6 thousand years ago. Its homeland is the tropical and subtropical regions of India and China, where it still grows naturally (Hardwick's cucumber). It is believed that the cucumber entered Europe thanks to the conquest of Southeast Asia by the ancient Greeks. The image of a cucumber can be found in ancient Greek temples. The Greeks called the cucumber "aoros". This word is translated as “unripe”, since the fruits were eaten unripe. The word "aoros" gradually became "auguros" (in Rus' it was paraphrased as "cucumber"). In France, cucumbers began to be grown around the 8th century, and a little later - in Germany and Spain.

Cucumbers most likely came to Russia from East Asia. And although the first printed mentions of cucumbers in Rus' date back only to the 16th century.

Cucumber in Russia ranks first in terms of area under protected ground. It was the first crop in Russia to be grown in protected soil. In the beginning (until the 18th century), cold beds and warm nurseries with light-proof shelters, steam beds, ridges and heaps (with manure as soil heating) were used for cucumbers. Since the 18th century, classic Russian greenhouses with biological heating (manure) began to be built. In the 19th century, semi-greenhouses with glazed frames and the famous Klin lean-to greenhouses with steam heating.

Cucumber is a widespread vegetable crop; it is grown everywhere in open or protected ground. Despite their popularity, the nutritional value of cucumbers is insignificant, since 95-98% of the mass is water. Fruits in a state of technical ripeness (greens) are used for food. Their nutritional value is low, but they are of great dietary importance. Cucumber fruits contain fiber and other carbohydrates, proteins, potassium salts, phosphorus, iron, carotene, vitamin C. The amount of sugars, depending on the variety and growing conditions, ranges from 1.3 to 3.0%, ascorbic acid - 3-28 mg per 100 g. They are consumed fresh, salted, pickled, prepared in salads and main courses. Cucumbers increase appetite and improve the absorption of proteins and fats. Fresh cucumbers have a choleretic, diuretic and laxative effect, reducing the acidity of gastric juice. In folk medicine, fresh cucumber juice is drunk as an analgesic and sedative for gastrointestinal colic and catarrh of the upper respiratory tract. Cucumber is an excellent cosmetic product.

1.2 Morphological and biological features of cucumber

Cucumber (Cucumis sativus L.) belongs to the pumpkin family (Cucurbitaceae). Annual herbaceous plant, branching stem, liana-like. Tendrils, shoots, male and female flowers are formed in the axils of the leaves. When directly sowing seeds into the ground, a tap root system is formed, penetrating to a depth of 0.8 - 1.5 m and a width of 1.2 - 1.5 m.

The seedling culture has a fibrous root system. The flowers are large, yellow, five-petaled. The plant is monoecious. Male flowers of 5-7 flowers form an inflorescence corymb. Women's singles or collected in 2-4 pieces. There are two groups of cucumber varieties - parthenocarpic, which form fruits without pollination, and bee-pollinated, which require pollination of flowers by bees for fruit formation.

The fruit is a fleshy false berry. The surface is pubescent or smooth. The pubescence can be simple, complex or mixed; the spines can be white or black. Greens with black pubescence have a yellowish tint; they quickly turn yellow. White-thorned ones have intense coloring. The leaves are five-lobed, petiolate, and have large tendrils and lateral shoots. The white seeds are flat and elongated.

Cucumber is a heat-loving plant, seeds germinate at soil temperatures above 12 o C, at a temperature of 18 o C seedlings appear on the 8th day, but the most favorable temperature for germination is 24 - 30 o C. A long period below 15 o C leads to death, high temperatures leads to the formation of a large number of male flowers. For the formation of female flowers, a nose temperature of 14-18 o C is required. Cucumber is demanding on air and soil humidity. Soil moisture 60-80% increase or decrease leads to a decrease in yield; air humidity 80-90%. A short-day plant, with increasing light intensity the internodes are shortened and the length of the main shoot decreases. When thickening occurs, the plants are suppressed, the internodes lengthen, the leaves die, and the yield is reduced. Cucumber requires well-aerated, humus-rich soil. You cannot apply chlorine-containing fertilizers PH – 6.5-7. Responsive to organic fertilizers. The root system requires active gas exchange. Cucumber is demanding of carbon dioxide.

Cucumber is native to the humid tropics of India and Indochina. On the territory of Russia, cucumbers appeared and became widespread even before the founding of Kievan Rus. In our country, cucumbers are one of the most favorite vegetable crops. Cucumber fruits are used both fresh and for processing: canning, pickling.

Cucumbers are valued not only for their taste, but also for their content of vitamins and mineral salts. Cucumbers contain carotene, vitamins C, B1, B2, folic acid, as well as trace elements: sodium, magnesium, iron, potassium, calcium, copper, phosphorus, zinc, chromium, silver, iodine.

Cucumbers are very good for health - they improve appetite, help absorb fats and proteins from other foods, and improve metabolism. Due to their low calorie content, cucumbers are recommended for obese people to include in their diet.

Botanical features of cucumber

Cucumber is an annual herbaceous plant from the pumpkin family. It has a long creeping, branching, 4-5-sided, pubescent stem. On the main stem, shoots of the first order are formed, on which shoots of the second order develop, etc. The main stem reaches a length of 200 cm, but when grown in greenhouse conditions, it can grow more than 5 meters. There are bush forms of cucumbers; they are characterized by stopping the growth of the main stem in a certain phase, for example after the formation of 10-12 nodes. On the stems, in the axils of 3-6 leaves, tendrils form, with them the plant clings to the supports and the vine grows upward, which allows you to grow cucumbers on a trellis.

Roots. The root system of the cucumber is taprooted and branched. Its development depends on soil and climatic conditions. In the middle zone and more northern regions, the bulk of the roots are located in the upper layer of soil, up to 30 cm. Individual roots penetrate to a depth of up to 80 cm. In the southern regions, with a lack of moisture, the roots grow superficially only at the beginning of growth, and then begin to grow deeper , up to 120 cm. If the soil is sufficiently moistened, then on the cotyledonous knee, during the period of intensive vegetative growth, many adventitious roots grow.

Flowers. Cucumbers are monoecious plants with dioecious flowers. Female, male, and less often bisexual flowers are formed on the plant. Female flowers are usually solitary, less often 2-4, with an ellipsoid or oval-elongated ovary on a short stalk. The ovary is three-petal-shaped, inside of which there is a stigma. Male flowers have a long stalk and five stamens containing pollen. Flowers are collected in inflorescences of 5-7 pieces. Male flowers usually bloom 1-3 days earlier than female ones. The structure of the calyx and corolla of the female and male flowers is the same, only the corolla of the female flower is larger than the male one. The corolla is yellow, five-lobed, wheel-shaped. The calyx is goblet-shaped, with five stamens (2 fused in pairs, 1 free). The ovary is inferior, pubescent, the stigma is tripartite. Bisexual flowers have a stigma, an inferior ovary and five stamens.

As the plant grows, flowers form in the axils of the upper rudimentary leaves. Which flowers there will be more on a plant, male or female, depends on the growing conditions, characteristics of the variety or hybrid. On the central shoots, more male flowers are formed than female ones, and on shoots of the first, second and further orders the ratio changes - the number of female flowers increases sharply.

Cucumber is a cross-pollinated plant; for pollination it needs insects: bees, flies, wasps, bumblebees, ants and others. Along with bee-pollinated varieties, there are parthenocarpic varieties and hybrids. In such varieties and hybrids, fruits develop without pollination; they are good for growing in greenhouses.

Fetus. The fruit of the cucumber is a meaty false berry (pumpkin) and has 3-5 seed chambers. Fruits vary in size, weight, shape, color, pubescence, depending on the variety.

By size, cucumber fruits are divided into 3 categories: pickles (length 3-5 cm), gherkins (5-9 cm) and greens (9-30 cm)

According to the shape of the fruit, cucumbers are ovoid, elongated-ovoid, cylindrical, elongated-oval, spindle-shaped.

The color of fruits at technical ripeness varies from light green to dark green, at biological ripeness from white to dark brown.

Fruit pubescence can be complex, simple or mixed. Hair color - brown, black, white. Fruits with black complex edges are well suited for pickling.

The fruits are eaten when they are technically ripe, have reached a certain size, are green in color, with watery seeds beginning to form. Sometimes the fruits are bitter. Bitterness appears in cucumbers under unfavorable growing conditions: low temperature, lack of light, nutrients, moisture, high temperatures and drought.

Seeds. Seed fruits contain 100-400 seeds. Cucumber seeds are white with a yellowish tint or light brown, elongated-elliptical in shape, 7-15 mm long, 2-3 mm thick, 3-6 mm wide, smooth. Germination remains for 6-8 years. For sowing, it is better to use 2-3 year old seeds, they produce more female flowers.

Biological features of cucumbers

Tropical origin determines the biological characteristics of the cucumber, the plant presents high requirements to heat and humidity, as well as to soil fertility and structure. Agricultural technology for growing cucumbers requires careful adherence to temperature and water conditions. As with growing other vegetables, there are secrets to growing cucumbers. Now in more detail about the features of this healthy and tasty vegetable, as well as how to grow it.

Temperature. Cucumber is a heat-loving crop. The temperature required for seed germination should not be lower than +15 degrees, the optimal temperature is +25+30 degrees. If the seeds are previously hardened and given the opportunity to hatch, they will sprout at a temperature of +10+13 degrees. If after sowing the soil temperature remains at +8+10 degrees, then the seeds will simply rot, which often happens with early sowing. The higher the temperature, the easier and faster the seedlings will appear. Shoots appear 5-6 days after sowing, at a soil temperature of +20 degrees and after 10 days if the soil has warmed up to +18 degrees.

For normal development, the plant, in the period before fruiting, requires a temperature of +20+28 degrees during the day, and at night - not lower than +12 degrees. During the fruiting period, the temperature is required higher: +24+30 degrees during the day and not lower than +16 degrees at night. When the temperature drops below +13+15 degrees, the root system absorbs nutrients and water worse, and plant development stops. A decrease in temperature to +8+10 degrees for 10 days or a decrease in temperature to + 3+4 degrees for 3-4 days leads to the death of plants. Cucumbers cannot tolerate frost at all.

At optimal temperatures +22+25, cucumbers begin to bloom 22-28 days after germination, bear fruit after 32-38 days, depending on the variety. With more low temperatures these periods are significantly increased.

Cold and wet weather over a long period harms cucumbers more than prolonged drought. Cold nights in summer and early autumn shorten the growing season of cucumber plants. Sharp temperature fluctuations cause stunted growth and death of roots. At high temperatures, above +42 degrees, plant growth stops.

Water mode. Moisture is one of the main components of success when growing cucumbers, since cucumber makes high demands on air and soil humidity. The reason for this is the poor development of the root system, its low absorption capacity and the large evaporating surface of the leaves. With low soil moisture and dry air, cucumber plants develop poorly, grow slowly, the first ovaries fall off, few fruits are produced and they are of poor quality.

The cucumber plant consumes the most water during the period of intensive leaf growth and fruiting. For normal development and growth, plants require 70-80% soil and air humidity.

Water for irrigation should be warm; watering with cold water can lead to disease and death of plants. Plants cannot be flooded, otherwise the roots will lack oxygen and nutrients, begin to rot, and the plant will grow worse. Weak watering is also not acceptable, especially during the period of active growth of vines. Watering should be carried out in the first half of the day, followed by ventilation of the greenhouses. If the humidity is too high, pollination deteriorates, flowers fall off, and rot appears.

Light. Cucumber is a short-day plant, but in our conditions, day-length-neutral varieties are usually grown. Although, when daylight hours during the seedling period are reduced to 10-12 hours, plant development accelerates, female flowers are more actively formed, and the period of fruiting is reduced. With a long day, a large vegetative mass grows, to the detriment of fruiting.

Cucumber is a light-loving plant and a lack of sunlight delays flowering for 1-2 weeks, and less nutrients accumulate in the fruits.

The soil. Cucumber requires structural, fertile soils. The cucumber plant is characterized by rapid growth and development, produces a harvest in a short time, so it requires a lot of nutrients. Cucumbers grow well in humus-rich soils with a high content of nutrients. These can be cultivated light or medium loams.

Cucumbers can be grown on loose soils by adding organic fertilizers and lime. Heavy clay soils must be “diluted” with loosening materials (coarse sand or old sawdust), peat, turf soil with humus.

The soil for cucumbers should be slightly acidic or neutral, since in acidic soil cucumbers absorb nutrients less well. Such soils must be “deoxidized” by adding lime, chalk, and ash.

Cucumbers require various macro and microelements for full development and fruiting. The most important are: nitrogen, phosphorus, potassium, calcium, magnesium, as well as boron, manganese, zinc, molybdenum and others.

At nitrogen deficiency, plants slow down, leaves turn pale green, then turn yellow.

Phosphorus is of great importance in the initial stage of plant development. Phosphorus deficiency delays fruiting, weakens the plant, leaves become smaller.

Calcium improves soil structure, reduces acidity, and stimulates root growth. At calcium deficiency White spots appear between the veins and along the edges of the leaves.

Potassium regulates metabolism in the plant, is easily absorbed, increases cold resistance, disease resistance, and improves the taste of fruits. At lack of potassium A pale yellow border forms on the edges of the leaves. The cucumber removes this nutrient most from the soil.

Magnesium plays an important role in the life processes of cucumber plants. At shortage magnesium, yellow spots (chlorosis) appear between the veins on old leaves. If the magnesium content in the soil is too high, the leaves darken and curl.

At boron deficiency, the leaves of cucumbers acquire an intense dark green color, the fruits are deformed, the roots and growing points die off.

The need for cucumbers nutrients depends on the stage of development. During the first 10-15 days, cucumbers need more nitrogen nutrition. During the flowering period, more phosphorus fertilizers are required, and when cucumbers begin to bear fruit, they need nitrogen-potassium fertilizer. Cucumbers especially need potassium in poor light conditions (cloudy weather, shading).

Introduction

Cucumber is a vegetable crop, an annual herbaceous plant belonging to the pumpkin family.

Cucumber is a tropical vine that has taken root in our gardens.

Moreover, this happened relatively recently, considering that five thousand years ago in India they also loved fresh cucumbers, and two thousand years later they discovered the taste of cucumbers pickled in tubs. The Egyptians valued cucumbers. Cucumbers came to the gardens of our ancestors from Byzantium. The Greeks who lived there called them "aoros", that is, unripe vegetables.

India is considered the homeland of the cucumber, where it was known more than 3 thousand years BC. e. This is a monoecious plant with a creeping or climbing stem. It has male flowers with stamens and pollen and females with a pistil, consisting of the lower ovary, style and stigma. Cucumber is an annual heat-loving cross-pollinating plant with dioecious flowers (some flowers are bisexual), belongs to the Pumpkin family. On one plant grow male flowers with stamens and pollen and female flowers with a pistil, consisting of an inferior ovary, style and stigma. Of all vegetable crops, cucumber is one of the most common and favorite vegetables. It is consumed throughout the year fresh, lightly salted, pickled and salted. Salads and okroshkas, soups and pickles are prepared from it. Nutritional value is determined by its unique taste qualities, which contribute to excellent appetite and absorption of food. Cucumber also has medicinal properties: promotes the dissolution of kidney stones, eliminates gouty tumors, prevents the development of atherosclerosis.

Morphological and biological characteristics of cucumber

Cucumber is a herbaceous annual plant, according to taxonomic categories:

Kingdom - Plants ( plantae)

Department - Angiosperms ( Magnoliophyta)

Class - Dicotyledons ( Dicotyldones)

Order - Cucurbitaceae ( Cucurbitales)

Family - Pumpkin (Cucurbitaceae L.)

Species - Common cucumber (Cucumis sativus L.)

According to morphological characteristics, a cucumber has this structure. (Figure 1) Leaves: arranged alternately. The solid, pentagonal-shaped, slightly lobed leaf blade has a deep notch at the point where the petiole is attached. The leaf, like the stem, is pubescent; the edge of the leaf has a jagged shape. The length of the shooting stem is 150-200 cm. Shoots of the first order, often equal to the main stem, are 2-6 in number. Next are the shoots of the second order. Cases of third-order shoots cannot be excluded. The morphological structure of the plant, in particular the length of the stem and shoots, is significantly influenced by the growing conditions. For example, in greenhouse conditions the length of the main stem of a plant can exceed 5 m.

Figure 1 - Morphological features of cucumber (Cucumis sativus L.)

The fruit of the cucumber is emerald green, bubbly, elongated, multi-seeded, juicy. This structure of the fruit is characteristic of this family and is called pumpkin. By botanical characteristics The cucumber fruit is false. The shape and size depend on the crop variety.

The cucumber fruit has three to four seed chambers. The shape is oval-triangular, sometimes tetrahedral. Edges with pronounced grooves. For varieties with dense green pulp, there are about ten longitudinal protrusions - “ribs”. The surface of the fruit is pubescent with hairs or spines, which are located on the tubercles. According to the size of the fruit, varieties are distinguished with small fruits - up to 8 cm, medium - 8-11 cm, large - 12-18 cm, very large ones reach 18 cm. The fruit of a cucumber contains from 100 to 400 seeds, depending on the variety and growing conditions. Full seed maturity occurs 30-50 days after flowering.

The vegetative part may slow down its growth and then stop altogether if the fruits are left on the plant until the seeds ripen. In this case, only shoots of the first and second order are formed; branches of the third order are completely excluded in this case.

In the case of timely selection of greens, the vegetative part continues to grow until the autumn cold snap.

For cucumbers, determinate and “bush” forms were identified. The bush form is characterized by cessation of growth after the formation of 10-12 nodes. For agriculture, such forms reduce labor costs for harvesting and weeding crops.

The type of root system of the cucumber root is taproot, branched (Figure 2). The main part (about 30 cm) is in the substrate. The main physiological property of this root system is its high absorption capacity.

Climatic and soil factors have a significant impact on the growth and development of cucumber roots.

The northern and central regions are characterized by location in the top layer of soil (up to 30 cm)

Figure 2 - Cucumber root

The maximum depth of root penetration can vary from 80 to 120 cm, while it is noted that for the first period of growth, the roots are located superficially, and then abruptly change their location to vertical.

During the period of intensive vegetative growth, if the soil is well moistened, numerous adventitious roots are formed on the subcotyledon. When drought occurs, these roots usually die.

The cucumber culture is characterized by the presence of female and male flowers in a monoecious plant. Female flowers are located in the leaf axil, singly or in pairs. An inflorescence of 5-7 flowers, presented in a raceme or corymb, is typical for male flowers.

In a cucumber, flowers are located at each node. Such a node contains a leaf, a bud, a tendril and a side shoot. The development of tendrils and lateral shoots occurs fully at each node. 3-5 nodes of the lower part of the plant do not have tendrils. A feature of the lateral shoots is their shortened shape, as well as the presence of leaf primordia and the absence of tendrils, therefore, later flowering and fruit development occur on these shoots. Late varieties of cucumbers tend to produce fruits on shortened shoots. These shoots represent a “fruiting reserve” that is used by the plant at the end of the growing season.

Nowadays, thanks to the work of breeders, varieties and hybrids of cucumber crops have been developed that are partially dioecy. These dioecious varieties have three plant types. The first are plants with " female type", they are characterized by female flowers. In turn, the "male type" is characterized by the presence of male flowers.

In the intermediate type of plants, equally male and female flowers are produced. Greenhouse farms mainly cultivate plants with the female type.

Based on the type of pollination, cucumbers can be divided into bee-pollinated and parthenocarpic (familyless). Bee-pollinated cucumbers are characterized by the flowability of pollen; their pollination occurs cross-pollinated, with the participation of pollinating insects. At the same time, single bisexual flowers sometimes appear on plants of ordinary dioecious varieties. Lack of pollination negatively affects the harvest and further reproduction of this crop. Parthenocarpic cucumber hybrids have many advantages compared to bee-pollinated ones: powerful growth and high foliage, standing density is 2-2.5 times less. Consequently, the result of these factors is the saving of seeds and seedlings, as well as a reduction in labor costs for caring for plants, and no costs for bees.

Cucumber is a heat-loving and moisture-loving plant. The temperature at which the growth process stops is below 14.5 0 C and above 42 0 C. The most intense growth of cucumber can be observed at temperature values ​​of 28-32 0 C.