Growing flowers in the autumn-winter period is associated with a number of difficulties, mainly caused by a lack of light. Thus, excessive elongation of stems as a result of elongation of internodes significantly reduces the value of flowers. Particularly undesirable is the elongation and associated weakening of peduncles, which sharply reduces the life span of plants. It turned out that modern retardants can prevent these negative phenomena.

The effect of retardants on cloves, a greenhouse crop of which is especially widespread, has been well studied. Carnation plants are sprayed twice or three times with a 0.25% solution of SSS, which leads to a reduction and strengthening of the peduncle, some shortening of the internodes without changing the diameter of the flower. Approximately the same results are obtained by watering the substrate with a 1% solution of alar. These changes improve the appearance and prolong the life of the flower.

Growth regulators are also recommended for processing cut carnations. The domestic industry produces the drug “Nora” intended for this purpose, which contains 0.07% alar and 0.04% hydroxyquinoline sulfate, as well as sucrose. Stored flowers are first placed in water for 2-3 hours, and then in the “Nora” solution, which can extend the life of cut carnations up to 40 days.

Some varieties of chrysanthemums react to alar in much the same way as carnations, so with the help of retardants it is possible to reduce the growth of plants in height, reduce the length and increase the strength of the peduncle.

To reduce the height growth of daffodils, tulips, and geraniums, you can apply treatment with an etrel solution at a concentration of 0.03-0.05%. Spraying many plants (for example, azaleas, roses, asters, zinnias, petunias, etc.) with a higher concentration of ethrel solution suppresses apical growth and promotes the formation of numerous lateral shoots. In recent years, numerous synthetic growth regulators have been created for use in floriculture. At the same time, new drugs are characterized, as a rule, by higher efficiency and a significantly lower level of phytotoxicity.

In developed countries, large areas are occupied by decorative lawns, the periodic mowing of which requires significant labor costs. Spraying the lawn in the spring with MMC in doses from 3 to 6 kg/ha effectively retards the growth of cereal grasses, which reduces the number of grass mowings. Since the tillering of plants becomes more intense, the decorative qualities of the lawn increase.

MMC is also used as a means of inhibiting the growth of shrubs in hedges. Typically, hedges are trimmed many times throughout the growing season as new shoots grow. This rather labor-intensive event gradually leads to a deterioration in the decorative qualities of the hedge, since when trimmed, the foliage of the plants decreases and the trunks are exposed. The best results are obtained by spraying the bush with a solution of hydrochloric acid. It is carried out at the very beginning of summer, when the bushes become well leafy. The concentration of the inhibitor solution varies from 0.25 to 1.5%, depending on the rock forming the fence. For example, to inhibit the growth of hawthorn, privet or yellow acacia, less HMC is required than for processing cotoneaster.

A hedge treated with GMK retains its given shape throughout the entire growing season, the plants remain green and well-leafed. In this case, a one-time haircut is sufficient, which is carried out in the fall or spring before the buds open. Thus, labor costs for maintaining the fence are reduced several times.

Ornamental gardening, becoming increasingly important, is becoming a serious consumer of physiologically active substances. It is not surprising that many new synthetic plant growth regulators first find application in this branch of crop production.

Plant growth regulators– natural or synthetic substances. They are used to treat plants in order to change vital processes or structure, to improve their quality, increase yield or facilitate harvesting. Regulators have an effect in small doses. Pre-sowing seed treatment has a beneficial effect on the growth of the seedling and increases its resistance to unfavorable environmental conditions and various pathogens, which contributes to the formation of stronger and more productive plants. Plant growth regulators increase resistance to lodging in plants; influence the expression of sex in a crop, which leads to increased seed production and increased yield. All growth regulators, both natural phytohormones and synthesized substances that activate individual phases of plant growth and development (organogenesis), are combined into a group growth stimulants.

Natural regulators include (auxins, cytokinins, gibberellins, ABA, ethylene, brassinosteroids, jasmonic and salicylic acids), through which the interaction of cells, tissues and organs is carried out; in small quantities they are necessary for the launch and regulation of physiological and morphogenetic programs. They are formed in certain organs or zones of the plant and transported throughout its body. They act in low concentrations, at the level of 10 -6 - 10 -12 M. However, it should be taken into account that phytohormones exhibit stimulating activity in a fairly narrow range of concentrations, the excess of which leads to inhibition and even death of plants (phytotoxicity, herbicidal effect).

A number of requirements are put forward for synthetic regulators: low consumption rates, rapid disposal in natural conditions, inability to accumulate in soil and food products. They are more stable in the plant body and are able to control their development for a long time.

Growth regulators that suppress or inhibit physiological or biochemical processes in plants, growth, seed germination and bud breaking are combined into a group growth inhibitors.

Natural growth regulators:

Auxins – phytohormones are predominantly of indole nature (indoleacetic acid and its derivatives). They induce cell growth by stretching. The precursor to auxin is the amino acid tryptophan. Auxins are produced and accumulated in high concentrations in the apical meristems (growth cones of the shoot and root). IAA can be released from a bound state (from glycosides, complexes with amino acids or proteins). They activate nucleic acid synthesis and division; stimulate cell growth by stretching, root formation (rooting of cuttings, formation of lateral and adventitious roots); participate in the differentiation of the root system, the gravitropic reaction of the root and stem. However, in excessively large doses they suppress root formation. They play a major role in growth movements - tropisms and nasties. In particular, they are responsible for phototropism - growth bending of organs in response to one-sided lighting; have an attracting effect. They enhance the formation of callus associated with cell proliferation near the wound surface; induce calcium permeability of vesicles; participate in temperature adaptation of the plant organism; reduce viscosity, increase permeability and speed of cytoplasmic movement; are an important factor in apical dominance (a phenomenon in which the presence of an apical bud prevents the lateral buds from awakening); participate in the regulation of phloem formation; activate enzymes that control phloem loading. Changes in auxin concentration are responsible for the natural separation of fruits or leaves.

The most common natural auxin in plants is indolyl-3-acetic acid (IAA). It is continuously destroyed by plant enzymes, while synthetic compounds are not subject to enzymatic destruction and therefore small doses can cause a noticeable and long-lasting effect.

More often in agriculture synthetic analogues of auxin are used: indolylbutyric acid (IBA), naphthylacetic acid (NAA), 2,4-dichlorophenoxyacetic acid (2,4-D), naphthoxyacetic acid, chlorophenoxyacetic acid.

IBA has high activity in stimulating root formation.

NAA is produced as a potassium salt, amide or methyl ester. Salt or NAA amide is used for thinning flowers and ovaries (apple trees, olives). NAA methyl ester is used as a means of delaying the germination of stored potatoes.

2,4 – D in high concentration is an effective herbicide for controlling weeds in cereal crops. Its positive effect on the balance of microelements in barley seeds was discovered. It prevents pre-harvest abscission of citrus fruits.

Naphthoxyacetic acid is used as a means of stimulating fruit formation (on tomatoes, strawberries).

To treat cuttings, prepare aqueous solutions of preparations, as well as powders and powder-based pastes. The concentrations of various substances for different crops are not the same (Table 8).

Table 8

Concentrations and duration of treatment of cuttings with aqueous solutions of growth regulators and vitamins (according to R.X. Turetskaya)

When using vitamins, the exposure of cuttings to treatment depends on the exposure of the rooting stimulant used.

Cuttings that cannot tolerate pre-planting soaking (leaves, herbaceous cuttings) are treated with powders and pastes. Such cuttings are immersed with the wet basal end in the powder or paste and immediately planted in the substrate.

Powders are prepared at the rate (1 mg per 1 g of talc or crushed charcoal): heteroauxin, IBA or NAA - 1-30, vitamin C - 50-100, vitamin B 2 - 5 - 10. A paste is prepared based on the powder or aqueous solution at the rate of 300 g of talc (or coal) per 1 liter of water.

In addition to aqueous solutions, alcohol solutions are also used, which contain in 1 ml of 50% alcohol (mg): heteroauxin - 8-10; indolylbutyric acid - 8 - 10; naphthylacetic acid - 4-6. Treatment of cuttings with an alcohol solution is carried out for 10-15 s.

Thus, synthetic auxins are used to enhance root formation in cuttings; obtaining parthenocarpic fruits; in order to prevent pre-harvest fruit drop in citrus and some pome fruits. In high concentrations, synthetic auxins are used as herbicides to control certain weeds.

Gibberellins- substances that promote strong elongation of plant stems. They belong to polyisoprene compounds and are synthesized from acetyl-CoA. The closest predecessor of the kaurena. They are synthesized in leaves and roots. Gibberellins induce germination of seeds and dormant organs; stimulate cell growth by stretching; participate in the regulation of flowering; increase the size of the fruits of seedless grapes. Treatment with phytohormone leads to the formation of parthenocarpic fruits. They are able to change the size, shape and number of leaves. The chlorophyll content in the treated leaves is reduced. More than 50 gibberellins are known. The main substance used in practice is gibberellic acid, or gibberellin A 3 (GK 3), which is obtained microbiologically. The concentration of gibberellin A 3 (GK 3) solutions for soaking or spraying is 0.0001-0.005%.

The stimulating effect of gibberellins on the growth of shoots in length, increasing doubleness and color, increasing the size of inflorescences and changing the timing of flowering was revealed on roses, cineraria, carnations, hydrangea, chrysanthemum, phlox, salvia, petunia, etc. In addition, treatment of bulbs and corms with gibberellins increases their reproduction coefficient accelerates the flowering of bulbous and corm crops. To obtain these effects, it is important to take into account the growth and development phase of the plant, since gibberellin stimulates the growth of those structures that have formed at the time of treatment. So, to increase the size of the inflorescences, enhance their color and doubleness, the treatment is carried out at the moment of complete formation of all elements of the flower, and to change the timing of flowering - when all parts of the flower are formed, but the buds are still green, and the longer the period from flower formation to flowering , the greater the acceleration.

The synthetic analogue gibbersib (sodium salts of gibberellic acids) increases the number of ovaries on the plant. The most common way to use gibbersib is to spray individual parts of the whole plant or apply drops of the suspension to buds and buds; for bulbs and seeds, soak them in the suspension for 4-12 hours.

A drug "Gerbamine", obtained by biofermentation from medicinal herbs, contains: N - 5.7 g/l, P - 2.7 g/l, K - 8.4 g/l, trace elements, gibbersib, amino acids and fatty acids, pH 5.7 . Recommended for feeding open ground perennials at the time of leaf growth; for irrigation use a 3% solution, consumption 10-15 l/m2, 2 for spraying - the same solution, consumption 10 l/100 m2.

Cytokinins – substances that induce division plant cells. All natural cytokinins are derivatives of isopentenyladenine. The place of their synthesis is the apical meristem of the roots. From the roots they are transported passively through the xylem to the above-ground organs. They stimulate cell division, synthesis of nucleic acids and proteins in isolated organs (for example, in pumpkin cotyledons); induce seed germination, promoting bud formation in whole plants and isolated tissues; activate shoot growth and inhibit root growth in length; enhance the growth of lateral roots; have an attracting effect; activate the metabolism of plant tissues, stimulate growth and biosynthetic processes in them; regulate nitrogen metabolism, photosynthesis, metabolite transport, chloroplast differentiation; keep stomata open; delay aging; control the formation of xylem vessels; induce stem morphogenesis. Sources of cytokinins are fruits and endosperm tissues.

Cytokinins (kinins) are used mainly in tissue culture to enhance cell division (cytokinesis) and tissue differentiation, and to induce active shoot formation in test tubes.

A synthetic analogue of cytokinin is BAP (benzylaminopurine).

In addition to the above substances, some natural substances of a non-hormonal nature - vitamins, some phenols, urea derivatives - also have the ability to stimulate the growth and development of plants. These substances, like phytohormones, are formed in plants in very small quantities, and not all of them easily move throughout the plant (for example, vitamins). They have a growth effect only in combination with phytohormones. In practice, they are used to enhance the effect together with growth regulators.

Brassinosteroids have growth-stimulating activity, which manifests itself in low concentrations (10 -6 – 10 -12 M); act as factors in the generative development of plants; reduce fruit drop, increase yield; play an important role in photomorphogenesis; increase resistance to disease and stress and induce the synthesis of polypeptides. They take part in the formation of nonspecific adaptive mechanisms.

Growth inhibitors are abscisic acid and ethylene.

Abscisic acid (ABA) belongs to sesquiterpenoids (C 15). ABA differs from natural inhibitors of the phenolic group (coumarin, salicylic acid) in that it inhibits growth in very low concentrations - 100 - 500 times less than substances of the phenolic group. The precursor is mevalonic acid. The phytohormone is synthesized in the leaves. It regulates germination; synthesis of storage proteins and lipids of the seed; seed ripening; falling of leaves and fruits; responses during pathogenesis and induction of resistance; stimulates the synthesis of proteins necessary during stress (heat and cold shock proteins; dehydrins, which protect proteins from denaturation during dehydration); induces the expression of genes that control the synthesis of aquaporins; accelerates the breakdown of NK, proteins, chlorophyll; closure of stomata (suppresses the channels through which potassium enters the stomatal cells and activates the channels that release potassium from the stomatal cells, which promotes the closure of stomata). When stomata close, ABA induces a rapid increase in calcium concentration in guard cells. In other cases, the effects of ABA appear after a long period of time and are associated with the regulation of various genes and proteins.

It was shown that the addition of ABA to nutrient media slowed down cell growth and reduced the synthesis of shikonin and its derivatives during the entire cultivation process.

It was found that ABA slows down the development of Arabidopsis thaliana seedlings by triggering the accumulation of the ABI5 transcription factor.

Lin and Kao indicated that the retardation of root growth in rice seedlings in the presence of ABA could be explained by the activation of ion-linked peroxidase.

Among synthetic analogs of ABA, only pentadienoic acid comes close to its ability to inhibit growth.

Xanthoxin is a substance similar to ABA in structure and physiological activity.

Some plants contain compounds functionally related to ABA. These substances quickly accumulate in the tissues of lower plants under damaging influences. These include lunularic acid (isolated from Lunularia cruciata); hydrangic acid (isolated from Hydrangea macrophylla). Lunular and hydrangic acids are formed from phenylalanine with the participation of phenylalanine ammonia lyase.

Ethylene gaseous phytohormone. The closest precursor is 1-aminocyclopropane-1-carboxylic acid (ACC). The main precursor of ethylene in higher plants is methionine. Ethylene is intensively synthesized in aging leaves and ripening fruits. In dividing and rapidly growing cells of young plants, more ethylene is formed than in those that have completed growth. It is assumed that the ethylene biosynthesis system is localized in the plasmalemma. The phytohormone inhibits cell division, growth in length and causes cells to grow in width. Causes epinasty (leaf curling - a mechanism of protection against excessive loss of water, the supply of which during flooding is reduced due to a decrease in hydraulic conductivity); falling of leaves, bending of petioles, inhibits the growth of seedlings, as well as the action of auxins, cytokinins, gibberellins; loosening of cell walls (ripening of fruits, formation of aerenchyma during flooding - air cavities through which air can enter the flooded roots). It is involved in the aging of cells, tissues and organs; participates in fruit ripening; influences the synthesis of odorous volatile compounds in fruits. Stress ethylene is thought to accelerate the rejection of damaged tissues or organs.

Estrel remains the main drug that produces ethylene when degraded in plant tissues. Estrel facilitates the separation of fruits and berries from the mother plant. It has been found that it leads to synchronized flowering of pineapples; significantly increases the productivity of Hevea.

Synthetic growth regulators and inhibitors:

Growth inhibitors comprise several groups that have a specific function: retardants, suppress stem growth; antiauxins inhibit the movement of 3-indoleacetic acid (3-IAA) and its analogues throughout the plant; morphactines disrupt the normal course of formative processes in the apexes of plants; stunners sharply stop the growth of all organs.

Of the inhibitors in floriculture, they are primarily tested retardants of synthetic origin, having the ability to limit the growth of shoots without reducing the number of leaves and significantly reducing the leaf surface, due to which a compact plant habit is created and the stability of peduncles is observed. In many cases, retardants accelerate flowering and inhibit the growth of unproductive shoots, thereby creating favorable conditions for the development of the main generative shoots. In general, they cause an effect similar to the effect of high-intensity lighting at low temperatures: plants have dense stems, short internodes, and intensely colored leaves.

The most widely used: CCC - chlorocholine chloride, or 2-chloroethyltrimethylammonium chloride (domestic preparations TUR and ZAR); alar- 2-2-dimethylhydrazide of succinic acid (B9, SADH, DYAC); etrel- 2-chloroethylphosphonic acid (ethephon); phosphon- tributyl-(2,4-dichlorobenzyl) phosphonium chloride (chlorophonium); atrinal- sodium salt of 2,3:4,6-bis-(1-methyl ethylidene)-0-(/,)-xylo-2-hexylfuronose acid (dikegulak, daikgulak). Retardants are used in concentrations of 50-200 mg/l, the processing methods are the same as for gibberellin, at a temperature of 12-23 0 C. There are practical recommendations for the use of retardants on annuals, biennials and potted plants. These recommendations are specific to each crop. However, it should be noted that the selection of a suitable retardant is carried out during experiments on each plant, since retardants act specifically. Thus, SSS has no effect on nightshades; only alar is effective for them. CCC is used in the form of a 0.5-1% solution for growing remontant cloves; treatment is carried out 3-4 times in the autumn-winter period at intervals of 10-14 days.

Substances with the action of auxins are used in the vegetative propagation of chrysanthemums, carnations, roses and other crops to treat cuttings in order to improve their root formation. The most widely used for this heteroauxin, rootin(a preparation based on (3-IAA), (3-indolylbutyric and ss-naphthylacetic acids, as well as vitamins B 1 and C.

Heteroauxin(beta-indoleacetic acid) has physiological activity and affects growth processes. One of the most widely distributed auxins. Heteroauxin is a stimulator of root formation in fruit, ornamental, tree and shrub plants; improves the fusion of scion and rootstock when grafting fruit crops; promotes faster development of shoots and leaves; antitranspirant.

Kornevin(5 g/kg indolylbutyric acid) root formation stimulator. Substances of indole nature stimulate root growth in plants, cuttings, and seedlings.

Kornevin is used for rooting seedlings; acceleration of root formation during cuttings; improving the survival rate of seedlings during transplantation.

Epin(0.025 g/l Epibrassinolide) has a growth-regulating effect and an anti-stress effect. Seed treatment increases germination energy and germination (accelerates the germination of grain and vegetable seeds). It enhances the protective functions of the cell, the synthesis of nucleic acids and proteins, enzymes, etc. Spraying plants stimulates the processes of photosynthesis and the absorption of nutrients due to more developed leaf apparatus and root systems. The drug improves tuber formation; stimulates resistance to late blight; helps reduce the content of heavy metal salts and nitrates; accelerates fruit ripening. It affects the content of dry matter, starch, vitamin C. Reduces the effect of stressful situations for wheat, barley, corn, rapeseed, soybeans, and potatoes.

It was shown that treating barley seeds and spraying crops in the tillering phase increased yield by 11-18%, including due to a reduction in the incidence of plant root rot and leaf diseases by 20%, compared to the control.

The effectiveness of using Epin has been shown on table beet crops. When pre-sowing beet seeds were treated with Epin, a significant increase in field germination was observed: in the Bordeaux variety - by 5%, Crosby - by 16%, Odnorostkovaya - by 6%. In all varieties, plant height, weight and number of leaves, and root weight were higher than those of plants grown from untreated beet seeds.

It was shown that treatment of Chinese cabbage plants with solutions of sodium selenate and Epin reduced the lead content, and the selenium content significantly increased. It is likely that the protective effect of the growth promoter against lead accumulation is mediated by selenium.

At a concentration of 0.12-0.25 mg/l, epin accelerates the germination of gladiolus corms, accelerates its flowering, increases the yield of children and the quality of the corms.

According to the GBS RAS, epin was used for cuttings of Korean chrysanthemums (concentration 0.125 mg/l, exposure 24 hours) and roses: ground cover, miniature, floribunda, hybrid tea and climbing roses (concentration 0.06 mg/l, exposure 18 - 20 hours). In all experimental samples, the quality of the root system and the number of rooted cuttings under the influence of epin approached the indicators obtained from the influence of IMC.

Zircon(hydroxycinnamic acid) activates the germination of seeds of grain, vegetable and tree plants, which contributes to the production of high-quality seedlings with a powerful root system. The growth regulator has growth-regulating and growth-stimulating effectiveness, which is associated with the activation of phytohormones and the protection of IAA through the mechanism of auxin oxidase inhibition; antibacterial, antiviral and fungicidal action. It promotes the rapid growth of the root and above-ground parts of planted and transplanted plants and ensures their survival and winter hardiness. The use of a growth regulator significantly increases the size and number of leaves (they quickly switch to root nutrition and use macro- and microfertilizers more efficiently).

It was shown that Zircon and Epin effectively act on the photosynthetic parameters of the assimilation apparatus of cucumber plants, which may indicate the possibility of their influence on the intensity of photosynthesis processes. They had a stimulating effect on the formation of generative organs of cucumber plants. It should be noted that these drugs not only increased the number of flowers, but also accelerated the intensity of their formation. It is assumed that Zircon and Epin influence the content of gibberellins, which are responsible for flowering processes in plants, or cause effects similar to the action of phytohormones. In wheat leaves, Zircon increased the intensity of photosynthesis and increased the chlorophyll content.

The drug has a pronounced protective effect against phytopathogens of various natures. Under stressful conditions, it helps to replenish missing biologically active compounds of an immunomodulatory and adaptogenic nature, enhancing the adaptive potential of cells, increasing their resistance to the effects of ionizing radiation, unfavorable temperature, water and light conditions and other types of stress. Zircon stimulates protective histogenic reactions of the affected tissue and increases repair processes in it. It has a protective effect due to the presence of caffeic, chlorogenic and chicoric acids.

When spraying potato plantings with Zircon, a decrease in the degree of damage to plants by late blight was noted; the increase in yield at a spray rate of 10 ml/ha was 20% of the control.

Zircon reduces the accumulation of heavy metals. It was established that pre-sowing treatment of spring wheat seeds with Zircon (2 ml/t of grain) and vegetative plants in the tillering phase at the rate of 10 ml/ha helped reduce the phytotoxic effect of cadmium when growing Irgina wheat in soil with a high content of this element, which manifested itself in stimulation plant growth and development and increased productivity. At the same time, a significant decrease in the transition of cadmium to the economically useful part of plants was noted.

Athlete(600 mg/l chlormequat chloride) is an unconventional plant growth regulator that prevents overgrowth of seedlings. Pre-sowing treatment of seeds with Atlet leads to the redistribution of assimilates from above-ground organs to underground, which ultimately causes shortening and thickening of the stem and proliferation of roots.

Athlete prevents lodging of winter and spring wheat and perennial cereal grasses; increases frost and drought resistance of tomatoes and fruits; prevents overgrowth of tomato seedlings; accelerates the beginning of fruiting of apple trees, pears, strawberries; increases the productivity of vineyards.

Growing fruit, vegetable and flower crops is not complete without the use of substances that improve productivity and accelerate plant development. Every gardener uses organic or mineral fertilizers at certain stages of growth, but it is not always possible to create optimal conditions.

Unbalanced soil composition, heat or frost reduce efforts to nothing. To increase the percentage of rooting and the resistance of the green organism to unfavorable factors, growth process stimulants are used.

What are stimulants?

These are special preparations made from biologically active substances - organic compounds that control specific vital functions: they affect growth, flowering, and fruit formation. These substances include:

• fulvic and humic acids;
• amino acids;
• vitamins;
• peptides;
• enzymes;
• proteins;
• polysaccharides;
• microelements.

Planting material (seeds, bulbs, tubers) and plant roots are treated with stimulating substances; they are also used for foliar feeding. Stimulants and growth regulators promote the production of phytohormones - organic substances that affect various processes of the plant body. Phytohormones include auxins, gibberellins and some other compounds:

1. 1. Auxins control the direction of growth: thanks to their action, the above-ground part grows vertically upward, and the root part - downward. They also stimulate cell growth and the formation of generative organs - fruits and fruit buds. Auxins are synthesized and accumulated in young parts of the plant (at the tops of fresh shoots).
2. 2. Gibberellins are the largest group of phytohormones. Concentrated in leaf blades, unripe fruits and grains. They influence the processes of seed germination and preparation for flowering.
3. 3. Cytokinins accelerate plant cell division and nutrient transport and inhibit the development of lateral roots. Another interesting function is slowing down the aging of leaves. A high content of cytolysins is observed in the root system and ripening seeds.
4. 4. Abscisins are antagonists of previous types of hormones. They have an inhibitory effect, which speeds up the ripening of fruits, seeds and buds, and prepares the plant for the dormant period. Water absorption by the root system is activated, while the respiration process is minimized. This effect of abscisins is used in the manufacture of drugs that increase crop resistance to drought and frost. Such hormones are synthesized in all plant organs in response to changing weather conditions, and accumulate in leaves and root caps.
5. 5. Brassinosteroids are involved in maintaining immunity. Thanks to the content of these phytohormones in the cells, the plant becomes more resistant to soil salinity, dry conditions and frost, and the negative impact of pesticide treatments is reduced (adaptogenic property). Brassinosteroids are found in young organs - immature pollen, seedlings - in microscopic quantities, therefore such substances are produced chemically.
6. 6. Ethylene stimulates seed growth. The presence of this plant hormone also causes fruit to ripen smoothly. Actively produced in all parts in response to exposure to the same ethylene. Leaf fall, flower color and aroma are also associated with the effects of ethylene.
7. 7. Jasmonates influence the formation of storage organs (tubers). Activate protective functions when attacked by pests and diseases.
8. 8. Polypeptide hormones, along with jasmonates, are involved in increasing immunity to damage by insects and diseases. An example of this type of hormone is systemin, which stimulates the production of jasmonic acid.

Phytohormones are formed in some parts of the plant and affect others. They have an active effect at very small concentrations (microdoses).

Types and properties

Both biologically active substances and phytohormones themselves can be obtained from plant or animal material - peat, coal, mushrooms, pollen, chitinous shells.

Some stimulants are produced exclusively by laboratory methods. In their properties, such compounds are almost no different from natural ones.

Natural preparations

They can be made at home using improvised means: nettle greens, aloe juice, yeast or bee honey. Such extracts are used to stimulate seed germination and micro-fertilizing of indoor and garden crops. Water from the container in which the willow twigs took root accelerates root formation.

A popular line of natural stimulants are humates. Humus is an organic substance, the main component of fertile soils. It is found in large quantities in peat and brown coal. Humate enriches the soil with microelements, improves its structure, serving as a breeding ground for beneficial microorganisms.

In the last few years, preparations based on seaweed have also appeared. The content of plant hormones and microelements allows these products to be used to increase sustainability and productivity.

Obtained by artificial (laboratory) method

These substances are synthesized in chemical production. Used in amateur and professional gardening. These include “Heteroauxin” and “Kornerost”, “Kornevin”, “Zircon”, “Krezacin”, “Epin”, “Atlet”, “Immunocytophyte”.

Methods of using stimulants:

• soaking seeds and tubers;
• watering the soil and plants;
• spraying (leaf treatment);
• soaking or dusting the cuttings and root system;
• local treatment (partial application to certain plant organs).

If the conditions of agricultural technology are violated - overwatering or drying out, severe damage by pests, lack of weeding - stimulants will be useless. They increase plant immunity, but do not eliminate the consequences of improper care.

The best stimulants

The use of stimulants helps increase yield by 1/3 and improve the quality of fruits. Thanks to timely treatment with drugs, plants cope more actively with stress factors (chemical exposure to pesticides, difficult weather conditions).

Classification of stimulants:

• agents that have an adaptogenic effect;
• rooting stimulants;
• plant growth stimulants;
• fruiting activators;
• substances to inhibit growth processes (inhibitors or retardants).

Humates

Available in powder or diluted concentrate form. Humic-based liquid preparations dissolve well in water.

They stimulate the reproduction and activity of microorganisms, which improve the chemical composition and structure of the soil (moisture capacity, air permeability). Thanks to humic compounds, metabolic processes in plant tissues occur more actively.

Sodium humate

It is a dark powder with an active ingredient content of 300 g/1 kg. Reduces the consumption of nitrogen fertilizers, increases yields by up to 20% and increases the accumulation of vitamins in fruits. Activates the synthesis of natural phytohormones, increases the rooting of seedlings. The effect of radionuclides decreases after treating plants with sodium humate. Before use, it is recommended to pour 5 g of powder - 1 heaped teaspoon - 1 l hot water(70-80 degrees). After 5-6 hours, filter the solution through a thick sieve or cloth. Apply:

• To soak vegetable and flower seeds, dilute the base at a rate of 1:10 (100 ml of stock solution per 1 liter). The grains are immersed in liquid for 1-1.5 days, then dried and sown.
• To water at the initial stage of seedling growth, add 10 liters of water to 1/2 liter of solution, and water the seedlings with the resulting liquid three times - after germination, after 12-20 days and at the beginning of budding.
• For spraying, prepare a solution of 1:20, as for irrigation. Process until the leaves are completely wetted.

You can improve the soil by adding 50 g of dry humate per 10 square meters. For uniform distribution, the powder is mixed with sand.

Potassium humate

More expensive in cost compared to sodium humate, but does not contain heavy metal impurities. Helps accelerate flowering and fruit formation, improve immunity.

The use of dry potassium humate is similar to sodium. The tubers are immersed in a 10% solution for a day or two. The cuttings are placed at a depth of 2-3 cm and kept for 5-6 hours. For spraying, dilute 1 ml of liquid humate in 1 liter of water, the frequency of treatments is 3 or 4 every 2 weeks.

Gumat+7

In addition to humic acids, it contains 7 microelements. Contains nitrogen, potassium, copper, manganese, zinc, molybdenum, cobalt, boron and iron.

One gram of the substance is dissolved in 10-15 liters of water. Used for watering during active growth once every 2-2.5 weeks. Consumption per 1 sq. m - 4-5 l.

"Baikal EM-1"

The biological product contains cultures of beneficial microorganisms. Restores soil fertility and improves soil structure. Increases plant resistance to low temperatures. How to use:

• To prepare compost, dissolve 0.5 cups of the drug in 10 liters of water and pour over organic residues - sawdust, plant tops, manure - evenly. Stir and cover with film for 2-3 weeks.
• For watering 1 tbsp. l. add to 1 bucket of water. The frequency of treatments is 1 time every 1-2 weeks.

"Athlete"

Belongs to the category of growth regulators. Causes a slowdown in the development of the aerial parts and thickening of the stems. The main part of the nutrients is distributed in the root system, stimulating its active growth and branching. "Athlete" accelerates the formation of ovaries and increases their number. For most treatments, dilute 1.5 ml of the drug in 1 liter of water. Used for watering:

• Solanaceous seedlings (tomatoes, peppers and eggplants) at the age of 3-4 true leaves. Carry out 1 treatment, distributing 30-50 ml of solution per plant.
• Cabbages at the 3rd or 4th true leaf stage. The frequency of watering is 3 every 7 days, the consumption rate is 1 liter per 1 sq. m.

For spraying: peppers and eggplants are sprayed once when they have the 4th leaf.

Tomatoes are processed three times with an interval of 6-8 days:

• 1st time - if there are 3-4 leaves with liquid of the same concentration (1.5 ml per 1 l);
• The next 2 times the amount of water in the solution is reduced (1.5 ml per 0.5-0.7 l). If the seedlings have to be kept without planting, it is allowed to process them a fourth time.

And flower seedlings and ornamental shrubs are sprayed with Atlet twice every 5-7 days. Flower crops - in case of stretching, bushes - during budding.

The positive aspect of the product: vegetable and flower seedlings do not stretch in conditions of low light and increased temperature. Processing is carried out strictly according to the instructions for use. Insufficient influence of the drug (single spraying) causes strong growth after 6-8 days, and an overdose - inhibition of plant development.

"Alar"

In contrast to Atlet, it is more often used to blunt the growth of ornamental and fruit crops. The inhibitory properties of N-dimethylhydrazide of succinic acid (the active ingredient of the drug) are also used in gardens for the purpose of actively laying fruit buds for next year's harvest.

The drug is not certified for use in private farms due to its high toxicity to fish. Industrial agricultural enterprises carry out the following treatments with Alar:

• spring spraying of winter varieties of apple trees to accelerate fruiting and prevent fruit falling before harvesting;
• treatment of the garden 2-3 weeks after flowering (solution concentration - 0.16-0.32%);
• watering low varieties of chrysanthemums to achieve a more compact, branched bush shape (0.15%).

"Heteroauxin"

Root formation stimulator, the active ingredient of which is β-indolylacetic acid (IAA). Helps activate cellular metabolism, increase regenerative capacity (the ability of cells to divide and form a new plant from its part). Improves seed germination, accelerates rooting of cuttings and seedlings of herbaceous and woody species. Thanks to the treatment with “Heteroauxin”, a high yield of daughter bulbs is obtained during propagation.

The substance has a powerful effect. An overdose leads to developmental disorders, so “Heteroauxin” is produced in the form of 0.1 g tablets: it is easier to control the consumption of the product in small portions at home.

The drug is almost insoluble in water. To prepare the solution, use medical alcohol. The operation is carried out wearing rubber gloves. The required number of tablets is placed in a spoon, a smaller device (a teaspoon) is applied with a rubbing motion and the tablets are crushed into powder. After pouring it into a small glass container with a tight-fitting lid, add alcohol (5 ml per 1 tablet). Shake, periodically heating the container in a container with warm (up to 70 degrees) water until completely dissolved. The liquid is then adjusted to the desired concentration.

Directions for use:

Processing sections of rootstock and scion before grafting grapes involves preparing a solution of high concentration - 1 g (10 tablets) per 1 liter of alcohol. There is enough liquid to lubricate 500 grafts.

Both the substance itself and the finished solution are kept in a dark place. Processing temperature - +18...+22.

"Kornerost"

Analogue of "Heteroauxin". The advantage of the drug "Kornerost" is ease of use.

The substance is in soluble capsules. Prepare the working fluid for several minutes, using water at room temperature. Methods for processing planting material correspond to those described for “Heteroauxin”.

"Kornevin"

The basis of the drug is indolylbutyric acid (IBA) 0.5%. Used to stimulate root formation and improve survival rate. "Kornevin" is produced in the form of a fine cream-colored powder. Methods of using the substance:

• the lower part of the cuttings is moistened with water, shaken and dusted with powder, planted in a substrate for rooting;
• When transplanting, the root system of seedlings is soaked for 6 hours in a suspension prepared at the rate of 1 g per 1 liter of water;
• the planted plants are watered with a similar solution after 7-10 days.

The suspension is prepared by diluting the powder in a small amount of hot (90 degrees) water, then bringing the liquid to full volume with cool water. The prepared solution retains its properties for 12 hours.

Good results are shown by the use of "Kornevin" in combination with other drugs:

• cuttings from a powerful plant will take root better when used in combination with Heteroauxin;
• rose shoots produce a strong root system using Zircon;
• weak shoots are rooted using “Kornevin” and “Epin”.

After planting rooted plants, it is advisable to fertilize with phosphorus or potassium-phosphorus fertilizers.

"Zircon"

It is a plant immune system stimulant. The active ingredient is hydroxycinnamic acids (caffeic acid, chicory acid, chlorogenic acid), dissolved in alcohol 0.1 g/l. A preventive remedy for diseases of fungal and viral etymology (late blight, downy mildew, scab, bacteriosis and others). "Zircon" accelerates the formation of roots during cuttings and transplantation; for this reason, its combination with rooting agents is unacceptable. Use with fertilizers will have a positive effect.

The solution is prepared by diluting the product in a glass, enamel or plastic container. First, take 1/3 of the volume of water at room temperature, mix thoroughly with the Zircon norm and add the remaining liquid.

The active acids of the drug are destroyed in the light within 30 minutes. The treatment is carried out in low light - in the evening, with exclusively fresh solution.

Use of the drug "Zircon". 1 ampoule = 1 ml = about 40 drops:

The product is quickly absorbed by plant organisms. 18 hours are enough for the drug to act.

"Epin"

Plant growth regulator that increases resistance to diseases and environmental stress factors. Reduces the content of heavy metal salts, nitrates and toxic substances in tissues. Improves germination, increases productivity and promotes rapid ripening of fruits.

The active component of "Epin" is epibrassinolide from the group of brassinosteroids. It is used as an independent stimulant and in tank mixtures with fertilizers, disinfectants and fungicides. At the same time, the consumption of pesticides is halved. It goes on sale under the name "Epin-Extra".

Using "Epin":

For preventive spraying of various crops, the following terms are used:

• nightshade and ornamental - 1-2 treatments at budding and beginning of flowering;
• root crops - after germination;
• cucumbers - 2 sprays: in the 3-4 leaf phase and at the budding stage;
• cabbage - a full leaf rosette;
• onion set - formation of the 4th leaf;
• fruit and berry - budding period with repeated treatment after 3 weeks.

Epin is environmentally friendly. The prepared solution is used within 24 hours. When exposed to light, the substance quickly decomposes.

"Pennant"

Complex adaptogenic drug. Consists of polyethylene oxide (PEO) 770 g/l and humic acid salts up to 30 g/l. Increases germination and productivity, resistance to unfavorable growing factors. Activates the development of beneficial microorganisms in the soil, enhances the effect of pesticides when used in tank mixtures and separately.

Using the "Vympel" stimulator:

New modifications to the line are the drug "Vympel-K", which enhances energy metabolism in cells thanks to succinic acid, as well as "Vympel 2". This product is enhanced by the carboxylic acids contained in it, which activate the processes of respiration and photosynthesis.

"Emistim-S"

The natural preparation "Emistim" is made on the basis of epiphytic mushrooms. Contains a number of phytohormones (cytokinins, auxins), carbohydrates, amino acids, microelements, and fatty acids.

Increases the percentage of germination and energy of seed germination, productivity, stimulates the development of a powerful root system and above-ground parts of plants. Increases resistance in difficult weather conditions, resistance to phytopathogens and pests, including nematodes.

The rate of treatment of seeds and tubers is 1/4 ml per 10 kg of material. For foliar application, 0.2 ml of the drug is enough to spray 1 hundred square meters of plantings.

Preparations with improved characteristics from this series are “Biolan” and “Stimpo”. They are used by amateur gardeners and farmers of large farms.

"Biosil"

A product of biological origin, obtained from the needles of the Siberian fir (Abies sibirica) plant. The main component - triterpene acids - is used to treat planting material and plants during the growing season.

Biologically active compounds stimulate the immunity of vegetable, fruit and ornamental crops. Processing wheat increases the gluten and protein content of the crop. The drug is completely safe, this quality allows it to be used for the production of environmentally friendly products, including baby food. Compatible with most pesticides - disinfectants, insecticides.

Directions for use:

1. 1. Treatment of grain seeds is carried out with a solution with a concentration of 0.05% (50 ml/10 l). A bucket of working fluid is enough to spray 1 ton of grain.
2. 2. Foliar feeding of cereals is used twice: during the tillering and heading period of plants. The liquid is prepared at the rate of 30 ml/300 l/1 ha of area.
3. 3. For tomatoes, apply 3 sprays during the formation of the 1st, 2nd and 3rd clusters. 300 liters of water are consumed per hectare with the addition of 50 ml of Biosila.
4. 4. Cucumbers are treated more often with a solution of lower concentration - 15 ml/300 l/1 ha. Sequence of spraying: on the 3rd leaf, at the beginning of budding, during the period of mass flowering and 1 week after the 3rd treatment.

"Immunocytophyte"

Arachidonic acid preparation. Strengthens resistance to diseases of fungal origin and bacteriosis. The durability of the effect is up to 2 months after treatment. Shows adaptogenic properties. Compatible with a wide range of insecticides.

Preparation of working fluid: 1 tablet is crushed and dissolved in 1-15 ml of water at room temperature, stirring occasionally for 1/2 hour. The concentrated solution is adjusted to the required proportion. Usually 1 tablet per 2 liters of water is enough for sheet processing of 50 square meters. m area.

Directions for use:

It is strictly prohibited to use the product before precipitation. Also, you cannot mix “Immunocytophyte” with biological products and alkaline compounds, potassium permanganate. An analogue of the drug is the stimulant "Obereg".

Gibberellin

The stimulating effect of gibberellic acids was discovered relatively recently and is stronger than that of auxins. Gibberellins stimulate the growth of above-ground parts of the plant at certain temperatures. Such drugs are used to increase yield and improve seed germination.

Stimulants that contain gibberellins: “Ovary”, “Fruitability”, “Bud”. Designed for foliar application. Particular attention is paid to fertilizing: on poor soils, the effect of gibberellin-type preparations will be ineffective or opposite to what is expected.

The use of stimulants does not replace fertilizers. Optimal results are achieved through the use of a complex of products. The action of various plant hormones and minerals is interrelated. When combined with proper growing techniques, it has a positive effect on plants.

The main retardants (chlorocholine chloride, alar, etrel)
About 20 retardants belonging to various groups of chemical compounds are used in global agricultural production. But the main attention is drawn to three: chlorocholine chloride (2-chloroethyltrimethylammonium chloride), alar (N-dimethylhydrazide of succinic acid) and etrel (a derivative of 2-chloroethylphosphonic acid).
Chlorocholine chloride (in our country produced under the name TUR, abroad CCC) is widely used in agriculture in many countries. This is an extremely effective and universal means of combating lodging of cereals. It also helps to increase the drought and frost resistance of grain crops. The use of chlorocholine chloride is necessary for long-stemmed, lodging wheat varieties growing in wet weather, when using high doses of nitrogen fertilizers. Spring wheat is sprayed with retardant in the summer at the beginning of the booting phase, and winter wheat in the spring at the end of the tillering phase. Only 4-6 kilograms of chlorocholine chloride are consumed per hectare. With mechanized spraying, the water consumption per hectare is 100 liters, and with the help of aviation - only 25.
As numerous tests have shown, chlorocholine chloride has found reliable use in vegetable growing, especially when growing tomato seedlings. Typically, the preparation of seedlings in greenhouses is carried out with a high seeding density and a lack of light. Because of this, elongated and weakened plants often grow. Spraying tomato seedlings at the moment when they have only formed two or three true leaves with a solution of chlorocholine chloride reduces the height of the stem by 1.5-2 times due to the formation of a short, thickened stem, which is very convenient for mechanized planting. At the same time, the number of true leaves increases and the root system becomes more powerful. Tomatoes treated with retardant produce more buds, flowers and ovaries. Maturation is thus accelerated by almost a week.
Today, when cultivating high-intensity varieties of apple, pear, cherry, sweet cherry and many other fruit crops, they try to limit their crowns. This can be done by pruning and bending the branches. But such operations require skilled manual labor. The search prompted chemists to create new regulators that inhibit plant growth. Based on N-dimethylhydrazide of succinic acid, a group of drugs was created under the trade name Alar.
Alar can work wonders. By treating apple or pear trees with it in the spring, you can slow down the growth of shoots and at the same time speed up the formation of flower buds and thus increase the yield next year. Fruit trees treated in the fall can delay flowering next year and avoid spring frosts. With the help of alar, they prevent the undesirable phenomenon of fruit falling before harvesting, and also accelerate ripening and even improve the color of fruits. Treatment of raspberry bushes reduces the length of the shoots by two to three times and thereby increases the frost resistance of the plants. Alar is superior in its effectiveness to many similar drugs.
But this substance also has disadvantages. For example, repeated treatments, especially of mature trees, are dangerous. They are overloaded with the harvest, which leads to sudden and long breaks in fruiting. In some varieties of fruit trees, after treatment with alar, the yield is sometimes lost. A negative feature of alar is its high stability and the danger of accumulation in the environment. Alar is harmless to humans and warm-blooded animals, but dangerous to fish. In this regard, in our country, alar is not used in industrial gardening. Our scientists are conducting research to create drugs similar to alar, but easily decomposed and less toxic.
Everyone knows how important it is not only to grow a crop, but also to harvest it, and then save it. Half of the total costs in gardening, or even more, are spent on manual labor for picking fruits and berries. While grains, potatoes and some vegetables are harvested from the fields using machinery, fruit collection still remains a challenge for agricultural machine design engineers. In recent years, mechanized harvesting of fruits and berries has been making its way into global industrial horticulture. So far, all modern fruit harvesting machines are based on the principle of shaking the harvest from trees and bushes. For the successful operation of such machines, it is necessary to simultaneously ripen the fruits and weaken their connection with the stalks or fruiting branches. But it turned out that not all valuable industrial varieties of fruit trees and berry bushes meet this requirement.
Plant physiologists knew about an unusual gaseous regulator of growth and development - ethylene. We have already talked about it in previous chapters. Let us remember: the action is expressed in the acceleration of maturation. But using gas in gardens is not very convenient. And here chemists came to the rescue - they created ethylene “generators” - powerful, easily soluble substances in water that facilitate mechanized harvesting.
An effective drug, etrel, was created based on 2-chloroethylphosphonic acid. In plant tissues, it decomposes into hydrochloric and phosphoric acids and ethylene, which has such a desirable physiological effect on the plant.
Spraying cherries, cherries, and plums with etrel in a concentration of 0.1 percent 10-15 days before harvesting accelerates ripening and the formation of a separating layer between the fruit and the stalk. Thanks to this, the harvesting machine manages to shake off almost all the fruit. From untreated trees, only one third of the fruit can be harvested by machine.
So, the creation of modern high-intensity and low-labor technologies for cultivating fruit and berry crops is a requirement of today. This is possible only with the close cooperation of design engineers, chemists creating synthetic regulators, and physiologists studying the processes of plant growth and fruiting.