Allelopathy - this “scary” term denotes only a simple interaction of plants and their influence on each other. Interact plants through the release of various volatile substances into the environment.
- Phytoncides, antibiotics, and the like substances secreted by plants form around them a kind of protective cloud designed to inhibit competitors and help plants of the same family and friends with them to develop.
Experienced gardeners have long noticed the peculiarities of the "behavior" of plants that grow in close proximity to each other. Over time, all the "oddities" found an explanation - quite scientific and logical. For example, in one year, under the same conditions, one plant develops and grows perfectly, and the other, for no apparent reason, is in a depressed state. Or the apple tree, which is fruitful before, suddenly becomes low-yielding, lags behind in growth, is attacked by pests and diseases. And it grows next to the cherry, which feels great - healthy and covered with fruits.
It is explained simply. In cherries, both roots and crown grow more intensively than in apple trees. And it is able to give root processes in large quantities. Its fast-growing "organism" emits a variety of allelepath substances that have a depressing effect on our apple tree.
Especially the issues of plant survival are relevant for small areas. The owners of small land should help the plants in which they are interested, to fight for life and prosperity. Of course, in all the plants that grow on our site, we are interested. There are several ways to “reconcile” antagonist allelopats with each other.
- We have a landing from north to south.
- We have rocks from west to east, according to the strength of growth.
- The most tall plants are placed in the extreme western row, since for photosynthesis the most efficient radiation occurs between 10 and 12 am.
- In the extreme western row, we also observe the ranking. Tall plants should be in the north and small plants should be in the south.
- Let's recreate a virtual garden and consider the theory with a concrete example. Plants of the extreme western row: cherry and sweet cherry. Cherries - north, cherry - south. Next row: plum and plum. Plum - north. Cherry plum - south. If you are going to grow apricot - here, to the north.
- The third row: apple and pear. Pear - north, apple - south. In the south, you can optionally plant a quince. Plants growing in such a sequence will not fight for precious solar energy and harm each other.
From fruitful combinations - basil and tomatoes. Basil improves their taste and protects against diseases. Dill does the same for cabbage. Of the active plants that have a beneficial effect on almost all garden crops, it should be noted chamomile, thyme, marjoram, lavender, chervil, thyme, sage, borage.
By the way, nettle, yarrow and white ash tree are also not weeds. That is, weeds, of course, but they help the plants to fight disease. Therefore, the benefits of them in the garden more than harm. They are very well cultivated around the perimeter of the entire site.
The development and growth of cucumbers suppress tomatoes - next to them in the same garden bed is contraindicated. Still tomatoes do not like turnips. Onions do not tolerate the neighborhood with beans, but loves beets and helps carrots to get rid of pests.
Tip! Do not destroy dandelions that grow under the apple tree. Their leaves produce ethylene, which accelerates the ripening and improves the taste of apples. In general, dandelion is a great neighbor for all vegetable crops. So stop treating it like a malignant weed. In addition, from the young leaves of dandelion in the spring, you can prepare a vitamin salad.
But the peas and mustard leaf - the perfect combination. A mutually beneficial partnership is also in peas with carrots and potatoes.
Between the rows of radish is good to plant watercress.
Garlic is the best helper and doctor for all plants, especially cucumbers, tomatoes, carrots, beets, strawberries. He, like chives, has a positive effect on roses.
Another uniquely positive plant is tarragon. The volatile substances that it releases have a beneficial effect on all vegetable crops.
- Larger pests, for example, rabbits - do not like garlic, marigolds, onions.
- Moles - the scourge of all gardeners - do not like the smell of narcissus and castor-bean.
- Mice, too, beware of land with garlic and polynya.
- Ants will not build an anthill where mint, wormwood, lavender, tansy, valerian grow.
- The larvae of the cabbage fly do not “digest” radishes, wormwood, marigolds, sage, and garlic.
- Carrot fly larvae are afraid of lettuce, onion and leek, rosemary, tobacco, wormwood and sage.
- Garlic and wormwood will not allow the apple moth to "roam".
- Slugs and snails go away from fennel, rosemary, garlic and parsley.
- A scoop can be brought out by planting geraniums, cosmos, marigolds, or by mulching plants with oak bark.
- Aphids are afraid of coriander, chives, marigolds, mustard, fennel, mint, nasturtiums.
- For convenience, we will compile a list in which we will reflect on what pests of the garden-garden do which plants scare away.
- The whitefly is afraid of nasturtium and peppermint, thyme and bitter wormwood.
- The cabbage blanket flies around with celery, mint, tomatoes and sage.
- Earthen fleas hate tobacco, tansy, mint, catnip, rue, cabbage and leaf lettuce.
- The five-point hawk moth is wary of dill, basil and borage.
- Cabbage caterpillars do not like dill, geranium, mint, garlic, nasturtium, onions, tansy, sage, wormwood and thyme.
- Colorado potato beetle can get rid of catnip, coriander, nasturtium, tansy, horseradish, onion, beans.
Allelopathic properties of soil
Allelopathy is understood as the chemical inhibiting interaction of plants and soil microorganisms as a result of the isolation of either physiologically active organic compounds or those appearing in the soils when their residues rot. The term "allelopathy" consists of two Greek words meaning "mutual suffering." Thus, allelopathy is the most important property of the living phase of the soil and has a great influence on the level of their fertility.
The phenomenon of allelopathy was noticed long ago both in the natural environment in forest, meadow, steppe and other biocenoses, and in agricultural practice in the cultivation of agricultural crops. However, the interaction of plants, soil microorganisms and other living organisms into account in the agronomic practice is extremely insufficient. Mostly the oppression of some plants by others is explained only by competition for light, water, nutrients, the development of pests and pathogens, deterioration of the physical properties of the soil, etc. The underestimation of the allelepathic interaction of organisms in the living phase of the soil limits the possibilities for increasing crop yields.
G. Molish, G. Grümmer, J. Bonner, A. G. Winter, E. Rice, S. I. Chernobrivenko, V. P. Ivanov, T. A. Rabotnov, 3. Lashtuvka, made a great contribution to the study of allelopathy. A.M. Grodzinsky, M.V. Kolesnichenko and many other scientists. For soil science and agronomic practice, these studies are of particular importance. Knowledge of allelopathy is also extremely important in environmental terms.
The most studied allelopathic interaction of plants and microorganisms. In order to characterize it, G. Grummer proposed using certain terms to designate inhibitors (inhibitors) of an allelopathic nature. The term antibiotic refers to inhibitors of biochemical processes produced by microorganisms and acting on microorganisms. The term phytoncide refers to inhibitors produced by higher plants and acting on microorganisms. Compounds secreted by microorganisms, inhibiting the biochemical processes of plants, called marasminami. The term colins are chemical inhibitors, formed by higher plants and acting on higher plants. However, there is a different focus of the action of inhibitors. Some antibiotics are toxic to higher plants, there are many phytoncides that inhibit the growth of higher plants, and many Colins that inhibit the growth of microorganisms, and some marasmins also act on microorganisms.
CHEMICAL COMPOSITION OF ALLOPLATIC NATURE INHIBITORS AND THE ORIENTATION OF THE MECHANISM OF THEIR EFFECTS
The main ways of biosynthesis of substances of alleleopathic nature and their chemical composition are partially established. E. Raie (1978) considers that all known inhibitors of the allelopathic nature can be divided into 15 groups. They are represented by a variety of simple and complex organic compounds. Most of the identified antibiotics, marasmins, phytoncides and colins can be attributed, according to E. Rais, to one of 14 groups.
1. Simple water-soluble organic acids, straight chain alcohols, aliphatic aldehydes and ketones.
2. Simple unsaturated lactones.
3. Long chain fatty acids.
4. Naphthoquinones, anthraquinones and complex quinones.
5. Terpenoids and steroids.
6. Simple phenols, benzoic acid and their derivatives, gallic acid and protocatechuic acid.
7. Cinnamic acid and its derivatives.
10. Condensed tannins, hydrolyzable tannins.
11. Amino acids and polypeptides.
12. Alkaloids and cyanhydrins.
13. Sulfides and glycosides of mustard oil.
14. Purines and nucleosides.
But some substances do not fit these groups, and it is advisable to allocate them to the 15th group. These are phenylacetic and 4-phenylbutyric acids, found among the toxins of decomposing rye residues, and phenylethyl alcohol, tryptophol, volatile ethylene inhibitor (CH2= CH2), abscisic acid, agropyrene, etc.
Inhibitors of allelopathic nature are not only released by plants on Wednesday, but are also found in stems, leaves, roots, flowers and inflorescences, in fruits and seeds of plants. Getting into the soil, they are part of its organic matter, and are also in the adsorbed state with the solid phase of the soil, in soil solutions and soil air (volatile toxins).
It has been established that alkaloids and coumarins strongly inhibit seed germination, phenolic toxins - seedling growth, cruciferous mustard oils - seed germination and the vital activity of microorganisms, tannins - powerful inhibitors of nitrification in soils, etc. Inhibitors can accumulate in soils and collapse.
The mechanisms of action of inhibitors are aimed at inhibiting cell division, suppressing growth, impairing the absorption of macro- and microelements by organisms, inhibiting photosynthesis, suppressing respiration, the degree of opening of the stomatal crevices, suppressing protein synthesis, changing membrane permeability, and inhibiting specific enzymes (cellulase, catalase, proteases, invertases, peroxidases, polyphenol oxidases, phosphatases, ureases, etc.), increasing plant sensitivity to certain diseases.
MANIFESTATION OF ALLELOPATHY IN NATURE SITUATION, IN AGRICULTURE AND GARDENING
Allelopathy has a great influence on the change in time of some biocenoses by others in certain areas of the earth's surface as a result of exposure to toxins produced by living organisms of biocenoses. Such a change in biocenoses is called succession. Successions occur as a result of changes in the growing conditions of plants under the influence of the vital activity of organisms that make up biocenoses, and under the influence of external causes, including agricultural activity of man. Consequently, allelopathy, like other plant relationships, underlies the emergence, development, and change of plant associations. It plays an important role in soil formation processes.
Agricultural activity of a person leads to a change of natural biocenoses by certain agro-biocenoses and a change in the direction of soil formation as a result of the use of a complex of agrotechnical methods. Under agrobiocenosis, new allelopathic relationships between organisms of the living soil phase are formed, new complexes of allelopathic compounds are being formed. Significant in this respect is a significant decrease in allelopathic inhibition of azotobacter and nitrifying bacteria after the development of forest sod-podzolic soils for arable land.
The allelopathic effect is manifested both in cultivated agricultural plants on weeds (in rye, flax, chickpea, buckwheat, etc.), and in weeds on cultivated plants. For example, the allelopathic effect of wormwood is expressed in reducing the germination of seeded bean seeds and in the germination of pea seeds, the creeper in the field inhibits oats, milkweed and flax flax - flax, sweet clover - corn, etc.
The phenomenon of fatigue known in agronomy is a vivid example of the manifestation of allelopathy under monocultures. Agricultural plants, growing on one field for a long time and releasing toxins into the soil, destroy themselves, even if the soil has an adequate supply of nutrients and is not infected with pathogenic microorganisms and other pests. Wheat root excretions adversely affect wheat roots, root oat excretions act on oats, flax on flax, and clover on clover. Soil fatigue is also observed in the cultivation of peas, cucumber, alfalfa, beet and other cultivated plants. This phenomenon is also found in fruit trees and shrubs.
There is a chemical interaction of seeds of weeds and cultivated plants during germination.
Along with other causes, the preservation of seeds in the soil from death for many years to their germination is related to the content of antimicrobial substances in the seeds of weeds of an allopathic nature. It is very important for cultivated plants that the seeds do not germinate during the pre-harvest and post-harvest periods. This is also a manifestation of allelopathy. For example, in sorghum this is favored by a high content in the seeds of tannins. Tannins also contribute to plant resistance to infection. It should be noted that substances that suppress the vital activity of both pathogenic and non-pathogenic microorganisms are found in hundreds of plant species.
It is necessary to take into account the allelopathic effect of decomposing crop residues on cultivated plants, especially when carrying out mulching tillage. The inhibitory effect of mulch consists of the action of toxins contained in the plant material of the mulch and the toxins produced by microorganisms that decompose the organic mass of the mulch. According to N. A. Krasil'nikov, from 5 to 15% of 1,500 cultures of actinomycetes suppressed the growth of higher plants, the same is observed in a third of 300 cultures of spore-forming bacteria studied by him and in 20-30% of spore-forming bacteria.
Allelopathic interaction was also observed in horticultural crops. Walnut releases a toxin that damages and even kills apple trees. The barberry, horse chestnut, rose, lilac, viburnum, and fir have significant allelopathic activity. Toxins of these plants inhibit neighboring plants and accumulate in the soil. The allelopathic interaction of the stock and the graft is shown during budding and grafting in horticultural crops. As a result, the growth of plants, their resistance to diseases, the terms of fruit ripening, their size, color and quality change. From the point of view of allelopathy, it is very important to carry out activities for the replantation of gardens.
Growing potatoes in between the rows of young apple orchards can lead to the accumulation of toxins in the soil that damage the apple trees. This reduces the nitrogen content in the roots and branches and changes the composition of proteins in the bark of apple trees, disrupts the process of photosynthesis.
Allolopathy plays a significant role in forestry. There are many species of woody plants that have an allelopathic effect on other types of woody plants or sometimes on plants of the same species.
Allolopathy is observed not only between plants and microorganisms. For example, some mushrooms are inedible to humans as a result of their toxic content. Known poisonous herbs not eaten by herbivores, etc. All these are manifestations of allelopathy.
Among living organisms, as a result of the release of chemicals, in addition to the negative interaction, there is also a positive one. Therefore, some researchers (G. Molish and others) suggest the phenomenon of allelopathy to be understood more broadly, and not only as an inhibitory effect of biochemically active compounds.
AGRONOMIC ACTIVITIES DECREASING ALLELOPATHIC IMPACT ON CULTURAL PLANTS
Many agricultural practices for farming purposes have yet to be developed. However, the importance of a number of activities that reduce the allelopathic manifestation of the living phase of the soil is beyond doubt. Here are some of them.
1. Cultivation of crops only in conditions of crop rotation.
2. Refusal from long-term permanent cultivation of crops in one field.
3. Weed control.
4. Тщательный подбор растений для смешанных посевов и посадок.
5. Регулирование травостоя естественных лугов и пастбищ.
6. Внесение в почву адсорбентов, снижающих содержание в почве подвижных токсичных веществ.
7. Известкование кислых почв для нейтрализации многих органических кислот аллелопатической природы.
8. Proper selection of vegetable crops (celery, next to cauliflower, protects it from blooming cabbage whitefish, carrots and onions protect each other from carrot and onion flies, etc.).
Test questions and tasks
1. What is allelopathy? 2. What are the groups of inhibitors of allelopathic interaction of plants and microorganisms? 3. Name the main chemical substances of the allelopathic nature and the direction of the mechanism of their action. 4. Give examples of allelopathic interaction of plants and microorganisms in natural conditions, in agriculture, in horticulture. 5. What do you know ways to reduce allelopathic effects in agricultural practice?
See what "ALLELOPATHY" is in other dictionaries:
allelopathy - allelopathy ... Spelling reference dictionary
allelopathy - interaction, alopathy Dictionary of Russian synonyms. allelopathy n., number of synonyms: 1 • interaction (5) ASIS synonym dictionary ... Synonym dictionary
Allelopathy - English allelopathy effect on each other of plant cargoes transported by ship, due to the release of gases: carbon dioxide, ethylene, ether, alcohols, aldehydes and other volatile substances. In cargo insurance, it is rated as risky ... ... Dictionary of business terms
ALLELOPATHY - (from Greek. Allelon mutually and. Patia) the mutual influence of plants on each other (slow growth, flowering, etc.) as a result of their release into the environment of various organic substances (antibiotics, phytoncids, etc.) ... Great Encyclopedic Dictionary
ALLELOPATHY - (from Greek. Allelon mutually and pathos suffering, the impact experienced), the interaction of plants through the release of biologically active substances (phytoncides, colins, antibiotics, etc.) in the external. Wednesday Sometimes A. is defined only as harmful ... Biological encyclopedic dictionary
allelopathy - Suppression of one plant species by another due to the release of a toxic substance [http://www.dunwoodypress.com/148/PDF/Biotech Eng Rus.pdf] Biotechnology topics EN allelopathy ... Reference book of a technical translator
allelopathy - The influence of the organisms of one population on the organisms of another with the release into the environment of waste products and the conversion of biomass into a mortmass ... Dictionary of Geography
Allelopathy - * alelapatyya * allelopathy interaction, which includes two different species, in which chemical compounds (eg, terpinoid compounds) released into the environment by individuals of the same species, inhibit the development of individuals of another species. Some plants ... Genetics. encyclopedic Dictionary
Allelopathy - (from other Greek. Ἀλλήλων (allelon) mutually and πάθος (pathos) suffering) the property of some organisms (microorganisms, fungi, plants, animals) to secrete chemical compounds that inhibit or inhibit the development of others. Also sometimes ... ... Wikipedia
Allelopathy - (from the Greek. Allēlōn mutual and páthos suffering) the influence of plants on each other as a result of the release of various substances. There are 4 groups of such substances. The substances of the two groups are formed by microorganisms, these are Antibiotics that suppress ... ... The Great Soviet Encyclopedia
The worst option for a gardener is when the representatives of the flora on his site are quite aggressive and have a negative effect through the soil on all its inhabitants. This may be manifested by slower growth, low yields or plant death. Substances can accumulate for quite a long period and manifest themselves for quite a long time.
Such cultures are a real find and pride. They are able to favorably influence their neighbors, increasing their yields to the maximum, improve development and rooting, in fact, in every way contribute to the process of life activity.
At the same time, they are able to destroy weeds and repel pests.
Is it possible to determine?
It is possible to determine allelopathic activity only by trial and error, that is, if you notice that crops grow poorly near or are dying, you should try to plant other representatives of this variety and watch. In cases where the positive dynamics are not monitored, it is worth thinking about the absolute incompatibility and planting of another culture.
How is allelopathy
The impact of the emitted chemicals can be of three types: 1. Negative - manifested in the inhibition of growth and development of neighboring plants, reducing the ability to winter, low yields, loss of crops. The excreted substances accumulate in the soil and gradually create an allelopathic environment that favorably affects some plants and inhibits others.
2. Positive - manifested in increased vegetation of neighboring crops, high yield and resistance of plants to environmental hazards.
This is due to the fact that some plants secrete substances that inhibit the growth of weeds, as well as preventing the spread of pests and various microbial and fungal diseases,
3. Neutral - this type of interaction does not affect the growth and development of neighboring plants.
How to determine the negative allelopathic effect?
It is rather difficult to determine the cause of the oppression of one or another plant variety, especially in the case of alleleopathic influence. For a start, factors such as soil quality, irrigation conditions, lighting, etc. should be excluded. We can only speak about the negative influence of neighboring plants as a result of the experiment. When the culture dies, a new plant of the same variety should be planted instead. If it dies again or is in a depressed state for inexplicable reasons, while observing all the rules of care, watering, soil selection, etc., then you need to think about the plants located nearby and their impact on the cultivated variety.
Allelopathic plant activity
Allelopathic activity is important to take into account when crop rotation. Most cultivated plants have weak allelopathic activity, unlike weeds, which rather easily inhibit other species, and generally worsen the condition of the soil. To avoid such problems, one can familiarize oneself with the main examples of the allelopathic influence of plants on each other.
Examples of crop incompatibility:
- Cherry is incompatible with such cultures as apple, pear, apricot,
- Beans with onions, garlic, celery,
- Squash with tomatoes,
- Cabbage with tomatoes, strawberries and beans,
- Potatoes with raspberries, pumpkin, cucumbers, tomatoes, sunflowers, cherries, apples,
- Carrots with celery, beetroot, horseradish,
- Peppers with beans, cucumbers, celery and fennel,
- Plum trees with pear, apple,
- Tomatoes with kohlrabi cabbage, legumes, cucumbers,
- Onions with beans and cabbage
- Radish and radish with legumes and strawberries.
Thus, if you properly distribute the various crops on the site, taking into account the allelopathic influence, it is possible to prevent the oppression and poor growth of some plants, to achieve high yields, while getting rid of pests and diseases.
"Fatigue" of the soil
These substances and their role in plant life are the essence allelopathy - the influence of plants on each other by various excretions into the environment.
Allocated substances not only protect their donor from enemies. They play a regulatory role in nature.
Have you noticed an amazing phenomenon - the change of dominants on some abandoned field?
Summer is coming the whole field turns yellow - this colza has covered it with its sunny flowers.
Next year The colza is almost invisible: the field is covered with a white robe — the daisy filled it.
On the third - it all fusions mature dandelions.
And finally in the fourth year the field is occupied by gradually accumulating iwan-tea. Such a shift over the course of several years could be observed on a long-abandoned collective farm field in the Yaroslavl province.
Nature did not create diversity of species in order to enable any one of them to occupy the whole earth. She provided an amazing mechanism: the plant produces not only protective, but also harmful substances. One copy produces very few similar substances. But the discharge of thousands, tens of thousands of plants of one species, grown and flourished in a limited area, is enough to “poison” the soil for themselves.
The following year, the seeds of the “pressed” plants either do not germinate at all, or feel oppressed and produce rachitic offspring. At the same time, the substance inhibiting growth for the seeds of another plant turns out to be a stimulant. And allows him to show his activity and become dominant.
This phenomenon underlies the so-called soil fatigue . It manifests itself not only in wild grass, but also in the garden, in the garden and even in the forest.
To avoid the "fatigue" of the soil, crop rotation and apply crop rotation, or horticulture. On the same bed one culture replaces another, and that, in turn, the third. In the end, everyone feels great and gives the maximum yield.