Perennial herb, 5-20 cm tall, with numerous thin roots. Stems solitary or not numerous, covered with hairs. The leaves are trifoliate, on long petioles (4-13 cm), the middle leaf is rhombic-oval on a short petiole, the lateral leaves are oblique-ovate, almost sessile.

Generative organs.

Flowers are white, 1.7-2 cm in diameter, usually bisexual. Fruits are false red berries, fragrant. Propagated vegetatively and by seeds.

Spreading.

Distributed in Europe, Western and Eastern Siberia, the Caucasus and Central Asia. It grows in sparse coniferous forests, on forest edges, clearings and old burned-out areas, less often among shrubs.

Used part.

The medicinal raw materials are fruits and leaves of strawberries. They are harvested quite mature, without stalks. Dried in well-ventilated rooms or dryers at a temperature of 45-65 C, pre-wither (in air or in dryers at a temperature of 25-30 C). Leaves are also harvested manually, while the remainder of the stem should not exceed 1 cm.Dried in well-ventilated rooms or dryers, the heating temperature of the raw material is 45 C.

Chemical composition.

Strawberry fruits contain up to 15% carbohydrates (glucose, fructose, arabinose, pectins), lemon, acetic, apple, formic, quinic, salicylic, folic and ascorbic (up to 80 mg%) acids, vitamins B 1, B 2, B 6, E. P, catechins, anthocyanins, leukoanthocyanides, tannins, phenol carboxylic acids, essential oils, traces of alkaloids, salts of iron, phosphorus, calcium, cobalt and manganese. Seeds contain a lot of iron.

Essential oils, vitamin C, carotene, alkaloids, aromatic and phenolic compounds, flavonoids and tannins are found in the leaves of wild strawberry. There are many tannins and iron salts in the roots.

Pharmacological properties of wild strawberry.

An infusion of strawberry leaves has a pronounced diuretic effect, which is associated with the presence of organic acids in the plant and a high potassium content. The ability of strawberry leaves to slow down the rhythm and increase the amplitude of heart contractions, dilate blood vessels, and also increase the tone and enhance uterine contraction has been experimentally confirmed. Leaves, due to the presence of vitamins, micro- and macroelements, are able to improve metabolism.

Strawberries have both a diuretic and a diaphoretic effect on the body. In addition, they have phytoncidal and antimicrobial properties, improve digestion and have an antithyroid effect.

Application.

Berries and leaves of strawberries are good and a remedy for various disorders in the body. The preparations of this plant are especially effective for blood diseases and metabolic disorders in the body. For diseases (gastritis, peptic ulcer, atonic constipation, digestive disorders), hypertension and atherosclerotic changes in the blood vessels of the heart, fresh strawberries have the best effect. Strawberry fruits and leaves have a good therapeutic effect for gout, arthrosis, arthritis, joint diseases, anemia, and kidney stones.

There is evidence of the positive effect of strawberry preparations for jaundice, dysentery, colitis, bronchial asthma, tuberculosis, enuresis, rheumatism, leukemia, scrofula, chills, uterine bleeding, chlorosis, C-avitaminosis, eczema, skin rashes. Broth, infusion and Fresh Juice strawberry leaves and fruits are also recommended as a tonic, wound-healing, anti-inflammatory and astringent agent. There is experience of their use for the rejection of necrotic masses in decaying tumors.

Due to the antimicrobial properties of strawberry juice, it is used as a gargle for various inflammatory diseases of the oropharynx and bad breath.

Application. Relatively often in some patients, hypersensitivity to strawberries, accompanied by allergic manifestations, is observed.

Dosage forms.

• 20 g of crushed leaves are poured into 200 ml of hot boiled water, infused for 2 hours. Take 1 tablespoon 3-4 times a day.
• Pour a tablespoon of strawberry leaves with a glass of boiling water, boil for 10 minutes, leave for 2 hours, filter. Take 1 tablespoon 3-4 times a day.
• Strawberry leaf tea. To prepare the tea leaves, the leaves are dried in the shade, twisted between the palms until the juice appears, poured into a box or baking sheet in a layer of 5 cm, covered with a wet cloth and fermented at a temperature of 26 C for 6-10 hours, and then dried very quickly. Brew and drink like tea, 2-3 glasses a day.

To grow any plant, including strawberries, you need to know the structure and physiology of the plant.
The stem of the plant consists of a rosette (also called a "horn") and rhizomes with roots. The horn is located above the surface of the earth, and the rhizome is in the surface layer of the earth (sometimes it rises above the surface of the earth). See fig. 1.
The rhizome has a main axis passing into a rosette and lateral ramifications. The internodes on the rhizome are short. An internode is the distance between two adjacent kidneys.
Strawberry roots are adventitious (see botany), they can be distinguished by the first and second order of branching.
Young plants have one horn, from the apical bud of which one peduncle develops. The apical bud dies off after fruiting. In the future, the horn develops due to the first axillary bud of the leaf, located below the dead apical bud.
In more developed plants, horns appear from the lateral branches of the stem (Fig. 2), as well as from the buds of the stem located in the leaf axils.
From the axillary buds, both horns that give flower stalks in the next year, and vegetative shoots - mustaches with rosettes can develop. Some buds may not produce horns or vegetative shoots (dormant buds).
The number of developed horns depends on the conditions of the year (the duration of the favorable period for the development of plants, agricultural technology, the availability of sufficient food and water, temperature and other factors). The most important period is the period after fruiting. At this time, the next year's harvest is laid, differentiation of tissues of future peduncles and their development takes place in the apical buds. During this period, the most important thing is to provide plants with water and intensive nutrition in sufficient quantities. Strawberries do not tolerate both excessive waterlogging and moisture deficit.
Mulching or hilling is also important, since from the base of the young horns developing from the axillary buds, new roots must develop, which are necessary for their nutrition. If there is no soil at the base of the new horns, then their nutrition will be insufficient, the roots of the main horn cannot provide sufficient nutrition for the developing young horns and the process of development of the generative organs of future peduncles will be disrupted. New horns may not produce peduncles if the process of development of the generative organs of the apical buds of new horns is not completed.
The process of development of generative organs can continue in spring, if conditions are favorable. It must be remembered that the process of development of generative organs occurs with a short day and moderate temperatures. The exception is neutral-day varieties of remontant strawberries, in which the crop is laid regardless of the duration of the daylight period. I will write about this in detail in another post.
That is why, under favorable temperature conditions and a lengthening of the growing season in autumn, as well as earlier warming of the soil in early spring, more horns will develop. And, consequently, the harvest will be greater. The number of horns can be judged by the thickness of the neck (the place where the rhizome passes into the horn).
In the spring of next year, flower stalks are distilled due to the accumulated supply of nutrients in the rhizome.
Vegetative shoots provide propagation rosettes. The mustache consists of two nodes and two long internodes. In the first node with a cover sheet, no rosettes are formed (with the exception of some varieties). Every second node gives a socket, from the lower axillary kidney of which a subsequent whisker grows. See fig. 2.
If the whisker is damaged after the first node, lateral branching is formed from it. In some varieties, lateral shoots are formed without damage. On the lateral shoots, the rosettes are weaker and are usually not used to obtain seedlings.
Each peduncle usually consists of 7 full flowers. See fig. 3.
The apical flower of the inflorescence produces the largest berries, the lateral flowers of each subsequent order produce smaller berries. Flowers of the fourth order of berries rarely give, and flowers of the fifth order of berries do not. During spring frosts, flowers of the first and second order are damaged, so large berries may not be obtained. With very early frosts, when only the first-order flowers (apical) are damaged, nutrients are spent on the development of the second-order berries and they will be larger than usual, there will be no significant yield losses. If frosts occur later, then crop losses will be significant.
The flowers of the strawberry are bisexual, have pistils and stamens. But there are exceptions. So, the late variety Pandora does not have stamens and for fertilization of the pistils it is necessary to plant another late variety next to it. See fig. 4.
In flowers, the number of stamens is a multiple of five from 20 to 35. The number of pistils depends on the variety, the position of the flower in the inflorescence and on the growing conditions. There are about 300-400 of them on the apical flower, and about 80 on the 4th order flowers.
The edible part of the strawberry is an overgrown receptacle. See fig. 5. It is not a fruit, since the ovary is not involved in its formation. According to modern classification, the edible is considered to be a false fruit. Strawberry is not a berry either, as it does not correspond to the botanical definition of the term "berry". But the name of the berry has a false fruit in everyday life, we are not talking about false fruits….
The fruits of strawberries are seeds located on the surface of the receptacle and attached to the tops of the pistils.
From Wikipedia: "Berry (lat. Bácca, úva) is a multi-seeded fruit with a thin leathery exocarp, a juicy intercarp and a hard intracarp, which forms a hard spermoderm (seed coat).
The fruit is coenocarpous, that is, formed from the spliced ​​gynoecium. The berry develops both from the upper ovary and from the lower; in the latter case, it bears a dried perianth on its apex, for example, in gooseberries, currants. If the ovary is multi-celled, then the berry is also multi-celled, for example, a two-celled berry - in a potato, a three-celled berry - in asparagus, a four-celled one - in a crow's eye, a five-celled one - in a lingonberry or Manchurian currant, etc. This type of fruit is typical for plants of very many families.
If not only the ovary, but also other parts of the flower (for example, a receptacle, like that of strawberries, strawberries and rose hips), takes part in the development of a fruit, which is similar in structure to a berry, then such a formation is called a false berry. True fruits (nuts) can be found both on the surface of the false berry (for wild strawberries and strawberries), and inside it (for rose hips); the very same fruit of these plants is more correctly called "multi-nut".
Around the core (cavity) are vascular bundles that feed all parts of the "fetus".
The "berry" is connected to the stem by the calyx formed by the sepals and the peduncle (the former pedicel).
The rest of the structure is clearly visible from the attached drawings.
The post used information from Ville Matala (Finland).

When growing strawberries, it is very important to know the features of its structure and physiology.

The strawberry plant consists of a rosette (the so-called "horn"), and rhizomes with roots. The horn should always be above the surface of the earth, and the rhizome is located in the surface layer of the earth. The main axis of the rhizome starts from the base of the rosette, and numerous lateral branches extend from this axis. Internodes on the rhizome, i.e. distance between two adjacent buds, short. The adventitious roots of the first and second order of branching extend from the rhizome of the strawberry.

Young strawberry plants have only one horn, from the apical bud of which one peduncle develops. After fruiting, the apical bud dies off, and a new horn develops due to the first axillary bud of the leaf, located below the dead apical bud. In well-developed plants, other horns develop, which arise from other axillary buds. In addition, from the axillary buds, not only new horns can develop, giving flower stalks next year, but also mustache with rosettes, i.e. organs of vegetative reproduction. At the same time, some of the kidneys remain inactive, i.e. "sleeping".

The number of formed horns developing on a particular plant is directly influenced by the soil and climatic conditions of the growing season (the duration of the period of plant development, temperature, the availability of sufficient nutrition and water, agricultural technology and other factors. At this time, differentiation of tissues occurs in the apical buds and the harvest of the next year is laid.Therefore, the plant during this period must be fully provided with water and intensive nutrition.At the same time, it should be remembered that strawberries cannot tolerate both excessive waterlogging and moisture deficit

Mulching and hilling play an important role in the life of strawberries, because from the base of the forming young horns, new roots begin to develop, providing them with nutrition, and they must be in moist soil. For this reason, if there is no nutritious soil at the base of the new horns, then their nutrition will be insufficient, since the roots of the main horn will not be able to provide sufficient nutrition for the young horns and the development of the generative organs of new peduncles will be disrupted. And if the conditions for the growth of the plant are favorable, then the process of development of the generative organs can continue in spring.

The development of generative organs occurs only with a short day and moderate temperatures, with the exception of neutral-day varieties of remontant strawberries, in which the setting of a crop does not depend on the length of daylight hours.

An important conclusion follows from this: under favorable temperature conditions and lengthening of the growing season in autumn, as well as earlier warming of the soil in early spring, more horns develop on strawberry bushes, which leads to an increase in yield. By the thickness of the neck, i.e. the place where the rhizome passes into the horn can be judged on the number of horns. Forcing of peduncles next spring occurs mainly due to the accumulated supply of nutrients in the rhizome.

Whiskers, which are vegetative shoots, serve for reproduction. Each mustache consists of two nodes connected by two long internodes. At the same time, in the first node of the strawberry mustache, which has a cover leaf, the rosette usually does not form, but the second node gives a rosette from which a new plant develops. A subsequent whisker immediately begins to grow from its lower axillary bud of this rosette. In some varieties of strawberries, in the first node, a lateral branch is formed, always giving outlets weaker than the main ones, therefore they are not used to obtain seedlings.

Each peduncle usually consists of 7 full-fledged bisexual flowers with pistils and stamens. The number of stamens in strawberry flowers is always a multiple of five and ranges from 20 to 35. The number of pistils depends on many factors (variety, position of the flower in the inflorescence, on growing conditions), therefore it is very variable and can vary from 300-400 at the top flower to about 80 on 4th order flowers. The largest berries are given by the apical flower of the inflorescence. Lateral flowers of each subsequent order produce smaller berries, flowers of the fourth order rarely produce berries, and flowers of the fifth order do not give berries at all. But there are exceptions to the general rule, such as the late Pandora variety - its flowers do not have stamens and for the fertilization of the pistils, another late variety must be planted nearby.

It is correct to call the edible part of the strawberry a "false fruit", since it is an overgrown receptacle, and the ovary does not take part in its formation. The real fruits of strawberries are its seeds, located on the surface of a juicy receptacle and attached to the tops of the pistils.

Spring frosts, especially late ones, are enemies of the strawberry harvest. If the flowers of the first and second order are damaged during spring frosts, then large berries can no longer be obtained. With very early frosts that damage only the apical flowers of the first order, nutrients are spent on the development of the second order berries and they will be larger than usual, so there will be no significant yield losses. Later frosts, damaging all flowers of the first and second order, lead to significant losses in yield ...

Introduction

Strawberries are one of the most popular, widespread and widely cultivated berry crops. It is valued for the high quality of berries, their early ripening, quick entry into the season of marketable fruiting, high productivity, fast and easy reproduction.

Strawberry fruits have excellent taste and delicate aroma, are widely used fresh and processed for making preserves, jams, syrups, pies, etc. It finds application in the perfumery industry for the fragrance of soaps, creams, lipsticks. But before you can enjoy it, it must be grown and preserved.

The purpose of this term paper is a consideration of the integrated protection of strawberries. Integrated plant protection is understood as a combination of biological, chemical, physical, agrotechnical and other methods against a complex of diseases in a specific ecological-geographical zone on a specific crop. Its purpose is to regulate the number of harmful species to an economically imperceptible size while maintaining the activity of natural beneficial organisms.

Integrated protection, to a greater extent than individual protective measures, contributes to the achievement of high economic indicators with the fullest observance of environmental requirements and a minimum negative impact on the environment.

Biological features

The structure of the strawberry bush

Strawberry is a perennial herb of the Rosaceae family, a berry culture. The strawberry bush consists of a perennial rhizome, annual horns with apical axillary buds, leaves, peduncles, whiskers with rosettes, etc.

Figure 1. The structure of the strawberry bush

The root system of strawberries is fibrous, branched, well developed (up to 60 - 62% of the total plant biomass). Consists of perennial rhizome, adventitious roots of the horn and lateral fibrous roots. Strawberry rhizome is a perennial modified stem, covered with non-falling stipules - scales. From the second or third year after planting strawberries, the lower part of the rhizome begins to die off. The older the rhizome, the smaller its apical growths and the weaker the root system.

The aerial part of the strawberry bush consists of annual horns with apical and axillary buds, leaves, peduncles, whiskers with rosettes. The leaf is complex, obtuse-toothed, usually trifoliate, but varieties with four and five leaves are found. The apical leaflet is ovate, on a short or long (depending on the variety) petiole, 2 lateral leaflets are sessile. Petioles of leaves in almost all varieties are pubescent; stipules are located in the lower part of the leaf, which differ in shape, color and size. During the growing season, plants have 2 waves of active leaf growth - in spring at the beginning of the growing season and in summer after harvest. A feature of strawberries is the lack of apical growth of the stem. From the apical flower bud in the spring, a peduncle with an inflorescence appears, which dies off after fruiting. New stems are formed as branches from lateral buds. Their length is 0.5 - 1.5 cm. They are called horns. Each horn ends with a flower bud.

The aboveground system has 3 types of shoots, which differ greatly in their morphological characteristics and biological functions:

Horns (shortened annual shoots). Each formed horn has an apical bud (heart), a rosette of 3 - 7 leaves, lateral axillary buds, at the base of the growth - adventitious roots. Peduncles are formed from the apical and axillary buds of the upper leaves for the next year. Axillary leaf buds are often vegetative.

Whiskers (annual creeping shoots) are organs of vegetative reproduction. A young daughter plant (rosette) develops on the second internode of the mustache. From the axils of the first leaf of the rosette, a mustache develops again, which gives a daughter plant of the second order at the second internode, etc. A lot of plant nutrients are spent on the formation of the mustache, which negatively affects the yield. Therefore, timely, 3-4 times during the growing season, the removal of the whiskers increases winter hardiness and productivity in the next year.

Peduncles that form in April from generative buds and live until the end of fruiting. On a flowering shoot, 1-2 stem leaves and an inflorescence appear. Most varieties have 4-12 peduncles on the bush, each having 4-10 flowers. The most favorable conditions for increasing the number of horns are formed in the first 3 years of life of fruit-bearing plantations.

The strawberry flowers are white, bisexual, but differ in stamens. In some varieties, the stamens are well developed, such flowers are called perfect, they can be pollinated with their own pollen. Varieties with underdeveloped stamens (Komsomolskaya Pravda, Miracle Ketena) require replanting of the pollinator variety. Strawberry flowering begins with the appearance of flowers of the first order, then - subsequent ones (according to their location in the inflorescence). Strawberries bloom 25-30 days after the beginning of the growing season, flowering lasts 15-35 days. It takes about 30 days from the beginning of flowering to ripening of the berries.

The strawberry fruit is a multi-nut. Its edible part is a strongly overgrown, colored, juicy, fleshy, sweet receptacle, on the surface of which, in the recesses, there are nuts formed from the ovaries of pistils. The size and weight of the berries depend on the variety, their location on the peduncle, the age and condition of the plants.

By the third or fourth year, the old parts of the rhizome begin to die off, the plant breaks up into separate parts, particulars. This phenomenon was called particularization. Particulation is a natural way of vegetative propagation of strawberries.

Morphological structure of strawberries

Strawberry is a perennial evergreen herb with a pronounced rhizome, in the upper part of which there are horns with rosettes of basal leaves.

Strawberry root - rhizome (modified stem). The root system is located at a depth of 25-30 cm. Strawberries tend to pull the rhizome deep into the substrate. This must be taken into account when planning the volume of the substrate and the size of the containers for planting. The rhizome lives for 2-3 years, then dies off. The diameter of the root system generally does not exceed the diameter of the bush itself. The optimum temperature for the roots is 18-25 ° C. The lower part of the rhizome becomes lignified over time.

Horns. Above the rhizome of the strawberry, stem annual formations are formed - horns. Each horn contains leaves, a flowering shoot with an inflorescence and a whisker. A newly rooted rosette of leaves has only one horn. By the end of the year, the horns become 2-3, in the second year it increases to 5-9, in the third - 8-16.

Strawberry whiskers are creeping shoots that develop from the axillary buds of the lower leaves of the horn. It is a chain of whiskers with several branching orders. Rosettes (daughter plants) appear on even internodes of a mustache of any order. On odd internodes, lateral branches are formed. A mustache of the second order develops from the bosom of the first leaf of the rosette, and looks like an extension of the mustache of the first order.

Strawberry leaves live 60 - 70 days. Leaves grow before flowering and after harvest.

The flowers are perfect, with normally developed stamens and pistils. Such varieties are pollinated with their own pollen. The strawberry cultivars that have flowers with underdeveloped stamens need pollination with other cultivars. Duration of flowering of one flower is 1-4 days.

Strawberry fruits are a false berry that forms from an overgrown receptacle. The fruits are achenes located on the surface of the berries.

Strawberry varieties. Strawberry varieties are divided into weakly and strongly branching. Normal fruiting, permanent and remontant varieties. Varieties of ordinary fruiting give one harvest per year, the rest of the time is used to build a mustache and flower buds for the next year's harvest. Varieties of constant fruiting, which bear fruit in waves with short breaks and produce a mustache throughout the growing season. Repaired varieties bear fruit in waves with short interruptions, but after the first fruiting there is a long interval when the plant grows a whisker, which does not grow later.

Biological features of strawberries

Strawberry is a perennial herb with a gradual renewal and death of leaves. The aerial part of the strawberry bush has three types of shoots:

The first type is horns, or shortened annual shoots, 0.5-1.5 cm long, they are formed after fruiting from the lateral axillary buds. Each horn consists of an apical bud, a rosette of three to five leaves, in the axils of which there are lateral axillary buds, and adventitious roots. From the apical and upper axillary buds, peduncles develop the next year, and from the lower ones - new horns and mustaches. Young plants ("whiskers") planted in spring have only one horn; by autumn, this annual plant can have 2-3 horns, in a biennial - 5-10, in a three-year-old - 8-16, etc. The number of horns most intensively increases in the first three years of the plant's life, then, as a result of aging, the horns are formed more slowly.

After the horn bears fruit and a mustache will develop from the lower axillary buds, and new horns will develop from the lateral buds, but, having lost all the leaves, it gradually turns into part of the rhizome.

The second type of shoots is the whiskers: thin, long, cord-like shoots that form from the lower axillary buds of the horn. On the cord-like shoots, there are nodes from which rosettes of leaves develop, capable of rooting, they are used for reproduction (often called whiskers). Increased whisker formation occurs after strawberry fruiting.

The third type of shoots are peduncles: organs that bear flowers. They develop from the apical and from the upper axillary buds. After fruiting, the peduncles die off.

Strawberry leaves grow during almost the entire growing season, but especially intensively - before flowering and after harvest; during the fruiting period, their growth slows down.

Fruit buds of strawberries begin to form and form in the year preceding the harvest, and these processes end only in the spring of next year.

The root system of strawberries is a perennial rhizome with lateral and adventitious roots that form on the horns. The bulk of the roots is located in the surface layer of the soil at a depth of 10-30 cm (depending on the degree of cultivation of the soil), individual roots penetrate to a depth of 50 cm and more. In width, the roots spread in the projection zone of the bush, and only some of them extend 10-15 cm beyond its limits.

In spring, the roots "wake up" first, 8-10 days earlier than leaves at a soil temperature of 7-8 °. Their growth continues throughout the growing season, but most intensively - in the spring and immediately after the end of fruiting. The best temperature for root growth is 14-30 °. The annual growth of the root system is due to the formation of adventitious roots at the base of the horns. And since with the age of the bush, lateral branches (horns) appear higher and higher from the soil surface, then the young roots also move away from the ground and are, as it were, in the air, therefore, the young roots must be covered with earth, but not spud.

Leaf growth begins in spring at a temperature of 6-8 °. Flowering occurs 25-30 days after the start of growth and lasts about 20-30 days, from pollination to ripening of berries takes 25-30 days.

Strawberry flowers are bisexual in most varieties, but in some varieties the flowers have insufficiently developed stamens or pistils, and they do not self-pollinate. Other bisexual varieties blooming at the same time are planted with such varieties.

Strawberries are not a winter-hardy culture: plants die at temperatures of -15 ...- 18 ° in the absence of snow cover. But in the presence of a snow cover 20 cm thick, strawberries can withstand frosts down to -25 ...- 30 °. Strawberry roots are sensitive to frost and freeze even at a temperature of -8 °. Damage to strawberries under our conditions is sometimes noted in years with cold, snowless pre-winter and in winters with strong thaws.

Given the biological characteristics of strawberries, it is advisable to grow them in one place for no more than 4-5 years.

Growth phases, stages of orthogenesis

During the growing season, strawberry plants go through several phases of development. Growth begins in spring at temperatures above 2-5 ° and intensifies with the onset of stable warm weather. During this period, growth is mainly due to the nutrients deposited in the stems, and partly due to the assimilation of overwintered leaves. In most areas of the Krasnodar Territory, the beginning of strawberry growth is usually noted in March, and on the Black Sea coast - in January - February. After 15-30 days, depending on the weather and the variety, flower stalks appear. This process takes 10-15 days. The growth of leaves in the spring is very rapid.

Strawberry bloom begins 10-15 days after the appearance of the peduncle. Duration of flowering of one flower is 4-6 days.

Uneven flowering of strawberries is associated with the special structure of the flower cluster. Strawberry flowers are collected in inflorescences (scutes, which have from 5 to 27 flowers or an average of 5 to 14 flowers). As a rule, one inflorescence develops from each heart located at the end of the horn. In it, flowers develop unevenly. First, the flower of the first order blooms. From the axils of the two bracts of this first flower, flowers of the second order are formed, and from the axils of flowers of the second order - flowers of the third order. The flowering process of the plantation lasts from 10 to 25 or more days, depending on the variety and weather. The last flowers can form at a time when the first berries are already ripe. It has been noticed that the latter flowers are often sterile. According to I. M. Kovtun, in varieties Koralka and Roshchinskaya, the percentage of such flowers does not exceed 3-4, and in the variety Belaya Pineapple it reaches 70. The percentage of sterile flowers increases under unfavorable conditions.

Strawberry varieties differ somewhat in terms of flowering time and duration. Usually early varieties bloom earlier, and later - later. Early varieties in the period preceding flowering require a smaller sum of effective temperatures - only 180-235 °, middle-term varieties - 223-276 ° and late varieties - 255-353 ° (according to the Pavlovsk experimental base of VIR).

The sum of effective temperatures before flowering over the years is not the same and fluctuates within relatively large limits. The higher the average daily temperature in the period preceding flowering, the shorter the period from the beginning of the growing season to flowering is.

The flowering time of strawberries depends not only on the average daily temperature and the sum of effective temperatures, but also on a set of other environmental conditions - air humidity, lighting period and its intensity, plant nutrition and other factors. Varieties with complex inflorescences, for example, Komsomolskaya Pravda, have the longest flowering time. However, the difference in the flowering times of strawberry varieties in the Kuban conditions is small and usually does not exceed 5-7 days. This is essential for matching pollinators to varieties with unisexual flowers. Based on this, it can be assumed that for the middle variety Komsomolskaya Pravda can be a pollinator of any variety of early, middle and mid-late ripening periods, since the flowering of all these varieties almost completely coincides.

After the end of the ripening of the fruit, the leaves are reinforced again and an increased growth of the whiskers occurs. However, in the absence of irrigation, this growth quickly stops, the whiskers do not have time to develop well, and the rosettes do not take root. Some of the leaves later die off and the rosettes remain unrooted. Under these conditions, the growth of new leaves begins only in September, after a decrease in the heat and precipitation. During this period, rooting of rosettes on the mustache also occurs.

With irrigation, the growth of leaves and whiskers of strawberries continues throughout the growing season. At the same time, the formation of new whiskers stops mainly in July, but their growth in length and the formation of new rosettes on them continues until October.

In the second half of August and early September, strawberry plants begin to grow. This period is extremely important, since at this time reserve nutrients are accumulated before going into winter, and the differentiation of fruit buds also occurs. Most varieties of strawberries are short-day plants, therefore, the differentiation of fruit buds in them occurs in a short autumn day at low temperatures, especially at night. Only in remontant strawberry varieties, differentiation of flower buds can occur during a long summer day, which determines the remontant property. In common strawberry varieties, differentiation of flower buds in summer is possible only under abnormal conditions: with heavy rainfall in late summer after a dry period, after mowing the leaves. Some varieties are more prone to secondary flowering in the fall. Most often, autumn flowering occurs in the Komsomolskaya Pravda and Dessertnaya Kuban varieties. Autumn flowering was also noted in the varieties Excellent, Joseph Magomet, Roshchinskaya. Usually, in the conditions of the Kuban in autumn, only single inflorescences bloom, which does not significantly affect the next year's harvest.

Climatic conditions, agricultural technology and varietal characteristics affect the timing of the laying of flower buds. Usually, early varieties finish differentiation of fruit buds earlier than later ones. Hot weather delays differentiation, and conversely, cool weather, watering and full mineral fertilizer contribute to its Haste.

Creation during the period of kidney differentiation of optimal conditions of moisture and abundant nutrition has great importance for the harvest of next year, since it is in the fall, and not in the spring, that not only the rudiments of inflorescences and flowers, but also pistils are formed in the fruit buds of strawberries. This is important because the pistils determine the number of achenes in the fruit and the more there are, the larger the fruit (within the same variety).

The quality and quantity of the harvest is also reflected in the degree of fruit development, which, in turn, is closely related to the normal development of hemicarps. Fruits with underdeveloped achenes never reach optimal sizes and, moreover, are ugly in shape. This physiological trait depends on the degree of development and vital activity of the stamens and pistils and is a varietal feature.

The difference in the timing of flower buds laying between individual horns of one plant can reach 10-14 days (the weakest lateral horns do not lay them at all), which predetermines the duration of the flowering and fruiting period of strawberry varieties.

It should be remembered that the reserves of nutrients accumulated in autumn determine a good wintering of plants and their spring growth.

The leaves of strawberry plants in the fall acquire an autumn color, specific to each variety, and then die off to a large extent. For the winter, only a small part of the leaves formed in the fall remains green. The strawberry plant gradually enters a state of winter dormancy, from which it emerges at the end of winter, before the onset of spring growth.