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Vegetative propagation plants- this is the development of new plants from vegetative organs or their parts. Vegetative propagation is based on the plant’s ability to regenerate, i.e., to restore a whole organism from a part. During vegetative propagation, new plants are formed from shoots, leaves, roots, tubers, bulbs, and root suckers. The new generation has all the qualities that the mother plant has.
Vegetative propagation of plants occurs naturally or with the help of a person. People widely use vegetative propagation of indoor, ornamental, and vegetable plants. For this, first of all, those methods that exist in nature are used.
Wheatgrass, lily of the valley, and kupena reproduce by rhizomes. Rhizomes have adventitious roots, as well as apical and axillary buds. The plant, in the form of a rhizome, overwinters in the soil. In spring, young shoots develop from the buds. If the rhizomes are damaged, each piece can produce a new plant.
Some plants reproduce from broken branches (willow, poplar).
Reproduction by leaves occurs less frequently. It is found, for example, in meadow heart. In moist soil, an adventitious bud develops at the base of the broken leaf, from which a new plant grows.
Potatoes are propagated by tubers. When planting a club, part of the buds develops into green shoots. Later, from another part of the buds, underground shoots, similar to rhizomes, are formed - stolons. The tops of the stolons thicken and turn into new tubers (Fig. 144).
Onions, garlic, and tulips reproduce from bulbs. When planting bulbs in the soil, adventitious roots grow from the bottom. Daughter bulbs are formed from axillary buds.
Many shrubs and perennial herbs are propagated by dividing the bush, for example peonies, irises, hydrangeas, etc.
Scientists have developed methods of vegetative propagation that are extremely rare in nature (cuttings) or do not exist at all (grafting).
Cutting-forging
When cuttings, part of the mother plant is separated and rooted. A cutting is a part of any vegetative organ - a shoot (stem, leaf), root. The cuttings usually already have buds, or they may appear under favorable conditions. A new plant grows from the cuttings, completely similar to the mother one.
Many indoor plants, Tradescantia, Pelargonium, and Coleus, are propagated by green leafy shoot cuttings (Fig. 145). Gooseberries, currants, nil, willow and other plants are propagated by leafless cuttings (a section of a young stem with several buds).
Begonia, glock blue, Uzambara violet, sansevieria (pike tail) and many other indoor plants are propagated by leaf cuttings. To do this, a separate leaf is planted in damp sand, covered with a glass cap, or placed in water (Fig. 146).
Raspberries are propagated by root cuttings.
Layerings
Layerings are used for propagating gooseberries, currants, and linden. In this case, the lower branches of the bush are bent to the ground, pressed and sprinkled with soil. It is recommended to make cuts on the underside of the bent branch to stimulate the formation of adventitious roots. After rooting, the cutting branch is separated from the mother plant and transplanted to a permanent place (Fig. 147).
Plant grafting
When grown from seeds, apple trees, pears and other fruit plants do not retain the valuable qualities of the original plant. They become wild, so such plants are propagated by grafting. The plant that is grafted onto is called the rootstock, and the plant that is grafted onto is called the scion. A distinction is made between grafting with an eye and grafting with a cutting (Fig. 148).
Inoculation
Eye grafting is carried out as follows. In the spring, during sap flow, a T-shaped cut is made on the bark of the rootstock. Then the corners of the bark are folded back and a bud cut from the scion with a small area of bark and wood is inserted under it. The bark of the rootstock is pressed, and the wound is bandaged with a special adhesive tape. The part of the rootstock located above the scion is removed.
Grafting with cuttings
Vaccinations are done by cuttings in different ways: butt (cambium on cambium), split, under the bark. With all methods, it is important to observe the basic condition: the cambium of the scion and the cambium of the rootstock must match. Only in this case will fusion occur. As with kidney grafting, the wound is bandaged. The sites of correctly performed grafting quickly grow together. Material from the site
Plant tissue culture
IN last decades Such a method of vegetative propagation as tissue culture has been developed. The essence of the method is that a whole plant is grown from a piece of educational (or other) tissue or even from one cell on a nutrient medium under careful observation of lighting and temperature conditions. At the same time, it is important to prevent the plant from being damaged by microorganisms. The value of the method is that, without waiting for seeds to form, you can get a large number of plants.
Vegetative propagation of plants is of great biological and economic importance. It promotes fairly rapid dispersal of plants.
During vegetative propagation, the new generation has all the qualities of the mother’s organism, which allows the preservation of plant varieties with valuable traits. Therefore, many fruit crops reproduce only vegetatively. When propagated by grafting, the new plant immediately has a powerful root system, which allows it to provide young plants with water and minerals. Such plants turn out to be more competitive compared to seedlings emerging from seeds. However, this method also has disadvantages: with repeated repetition of vegetative propagation, “aging” of the original plant occurs. This reduces its resistance to environmental conditions and diseases.
For a long time, people, cultivating plants, began to use vegetative propagation. For example, growing potatoes, strawberries, banana in all countries of the world it is carried out only by vegetative means - tubers, tendrils and rhizomes.
The use of vegetative reproduction of plants in agricultural practice is called artificial vegetative propagation .
The main methods of artificial vegetative propagation come down to repeating those that occur in plants under natural conditions.
People often use propagation by cuttings - parts of green or woody shoots (grapes, currants, gooseberries, roses, cloves, ficus ) , tubers (potatoes, dahlia, sweet potato, Jerusalem artichoke ) , leaves (saintpaulia, gloxinia, begonia) , bulbs (onion, garlic, tulip, narcissus ) , dividing the bush (currants, pyrethrum) and layering (gooseberry, honeysuckle, clematis) , mustache (strawberry ), rhizomes (sugar cane, irises, phlox ) , root shoots (plum, raspberry, cherry, lilac ) .
In agricultural practice, forms of vegetative propagation of plants are used that are not found in wildlife. Among them, propagation by grafting and tissue culture is widely represented.
Graft, or transplantation(from lat. transplantation- “transplantation”) is the transplantation of vegetative parts of one plant to another and merging them with each other.
With this method of propagation, one of the grafted plants has its own root system, and the other, fused with it, has no roots and feeds on the roots of another plant.
The plant that is grafted onto is called rootstock , and the plant that is grafted onto the rootstock is scion .
IN agriculture vaccinations are of great practical importance. Growing varietals fruit trees always carried out by vaccination.
Most often, two types of grafting are used: a cutting and one bud - an eye.
For cutting grafting Cut annual shoots with 2-3 buds are usually used as a scion. They are attached to the rootstock. Typically the scion is placed between the bark and the wood, where the cambium layer is located. In this case, it is important that the cambial layers of the scion and rootstock coincide. This ensures the success of shoot fusion.
Eye vaccination (one kidney) is called budding (from lat. oculus- "eye"). Due to the ease of budding, it is most often used by gardeners. When grafting with one kidney, fusion occurs faster than with other methods. It is only important that the cut eye has a small area of bark and cambial layer. In this form, the scion is placed in a cut under the bark of the rootstock and strengthened with tying (duct tape or polyethylene). The fusion of the eye with the rootstock occurs after 10-15 days.
Grafting is usually done in the spring, when the plants are actively flowing sap, or in the summer. Cuttings are usually prepared in winter; they are cut from strong, healthy trees from shoots that have well formed buds. The cuttings are stored until spring in a cold place, usually under snow. At the time of grafting, the necessary eyes are cut off from the cuttings.
Tissue culture. Growing plants from cells or pieces of tissue is called tissue culture . This method is based on the ability of a plant cell to form an entire organism. From one mother plant, more than a million daughter plants with previously known properties can be obtained in a year. Tissue culture is used to grow virus-free potatoes, ginseng, orchids and other ornamental plants. Tissue culture is grown in special laboratories on nutrient media, under sterile conditions at a certain temperature, humidity, and lighting.
You can get a new plant from the tissue of any organ. Usually they take pieces of tissue from the tip of a root or shoot, or a piece of leaf. Sterilize and transfer to a nutrient medium. The cells grow quickly and gradually form a small plant.
It is important that the tissue culture method can quickly obtain a large number of valuable medicinal or ornamental, as well as rare and protected plants. Often those that do not reproduce vegetatively by other means. Despite the high cost and labor intensity, this method of vegetative propagation is justified and is very promising.
Vegetative propagation is used in agricultural practice. Its value lies in the fact that the vegetative method of propagation allows the almost unchanged qualities of the mother plant to be passed on to the daughter plants. Grafting and tissue culture are methods of vegetative propagation introduced into the plant world by humans.
Reproduction is the ability of all organisms to reproduce their own kind, which ensures the continuity and acceptability of life.
| Sexual | Asexual |
| Two organisms involved | One organism involved |
| Involved sex cells (gametes) obtained by meiosis | Somatic cells that reproduce by mitosis are involved. |
| The children turn out to be different (a recombination of the characteristics of the father and mother occurs, the genetic diversity of the population increases) In evolutionary terms, it appeared later. occurs under unfavorable conditions. characteristic of eukaryotes Meaning: |
Children turn out identical, copies of the parent (in agriculture - allows you to quickly increase the number of organisms, preserving all the characteristics of the variety). This is the oldest form of reproduction. Occurs under favorable conditions. Maintains characteristics in stable, unchanging conditions Meaning: |
Methods of asexual reproduction
1) Division in two(amoeba and ciliates are divided by transverse division, green euglena is divided by longitudinal division).
2) Sporulation
- Spores are specialized haploid cells. Spores of fungi and plants serve for reproduction. Fungal spores are formed by mitosis, and plant spores are formed by meiosis.
- Sp bacterial pores do not serve for reproduction, because One spore is formed from one bacterium. They serve to survive unfavorable conditions and dispersal (by wind).
3) Budding: daughter individuals are formed from outgrowths of the body of the mother organism (buds) - in coelenterates (hydra, sea anemone, corals, jellyfish), yeast - unicellular fungi
4) Fragmentation: The mother organism is divided into parts, each part turns into a daughter organism. (Spirogyra, coelenterates, starfish.) Based on regeneration.
5) Vegetative propagation of plants: reproduction with vegetative organs:
- roots – raspberries
- leaves - violet
- specialized modified shoots:
- bulbs (onion, tulip)
- rhizome (wheatgrass, iris, lily of the valley)
- tuber (potato, Jerusalem artichoke)
- mustache (strawberry)
Methods of sexual reproduction
1) With the help of gametes, sperm and eggs. Hermaphrodite is an organism that produces both female and male gametes (most higher plants, coelenterates, flatworms and some annelids, mollusks).
2) Conjugation green algae Spirogyra: two filaments of spirogyra come together, copulation bridges are formed, the contents of one filament flow into the other, one filament is formed from zygotes, the second from empty shells.
3) Conjugation in ciliates: two ciliates approach each other, exchange reproductive nuclei, and then separate. The number of ciliates remains the same, but recombination occurs.
4) Parthenogenesis: a child develops from an unfertilized egg (in aphids, daphnia, bee drones).
Are the statements true?
Sporulation is characteristic of hydra. -
Green euglena reproduces by cell division. +
Asexual reproduction involves one individual. +
A hermaphrodite is a bisexual organism. +
Mosses and ferns reproduce by budding. -
In asexual reproduction, the offspring are genetically very different from the parent organisms. –
Protozoa are characterized by halving. +
Reproduction is the process of reproducing others like themselves. +
Hydra reproduces by budding. +
Grapes, currants, gooseberries, and willows are propagated by cuttings. +
Asexual reproduction involves one individual. +
37 tests on the topic (Zubrominim website)
1. During parthenogenesis, the organism develops from
A) zygotes
B) vegetative cell
B) somatic cell
D) n unfertilized egg
2. In agricultural practice, vegetative propagation of plants is often used to
A) get a high yield
B) increase their resistance to pests
C) increase their resistance to disease
D) get mature plants faster
3. The daughter organism is most similar to the parent during reproduction
A) sexual
B) seed
IN ) asexual
D) with alternating generations
4. In agricultural practice, the vegetative method of plant propagation is often used to
A) to achieve the greatest similarity of the offspring with the parent organism
B) achieve the greatest difference between the offspring and the original forms
C) increase plant resistance to pests
D) increase plant resistance to diseases
5. The daughter organism is more different from the parent organisms during reproduction
A) vegetative
B) using spores
B) sexual
D) budding
6. Gametes with a haploid set of chromosomes participate in reproduction
A) using spores
B) vegetative
IN) sexually
D) budding
7. The method of reproduction of aphids, ants, wasps, in which a daughter organism develops from an unfertilized egg, is called
A) parthenogenesis
B) spore
B) budding
D) vegetative
8. Reproduction, in which a daughter organism appears without fertilization from the cells of the body of the mother organism, is called
A ) parthenogenesis
B) sexual
B) asexual
D) seed
9. Parthenogenesis is characteristic of
A ) aphids
B) worms
B) bacteria
D) protozoa
10. Parthenogenesis is the process of development of an organism from
A) unfertilized egg
B) somatic cells of the mother
B) haploid spores
D) zygote formed as a result of the fusion of gametes
11. The method of propagating raspberries using root suckers is called
A) generative
B) budding
IN) vegetative
D) seed
12. The reproduction of some insects through parthenogenesis promotes
A) increasing the viability of offspring
B) improving adaptation to the environment
C) enrichment of the heredity of offspring
G) rapid increase in animal numbers
13. Gametes are specialized cells with the help of which
A) sexual reproduction
B) vegetative propagation
B) budding
D) regeneration
14. The sexual method of reproduction includes the process
A ) parthenogenesis in bees
B) budding in yeast
B) spore formation in mosses
D) regeneration in freshwater hydra
15 During the sexual reproduction of organisms, offspring experience
A) complete reproduction of parental characteristics and properties
B) p recombination of traits and properties of parent organisms V
C) maintaining the number of females
D) predominance of males
16. During sexual reproduction, as opposed to asexual
A) the daughter organism develops faster
B) population numbers increase
C) more females are born
G ) genetic diversity of offspring increases
17 Asexual reproduction occurs in
A) flowering plants with seeds
B) birds laying eggs
IN) hydr budding
G) coniferous plants seeds
18 The set of genes in a daughter organism differs significantly from the set of genes in parent organisms during reproduction
A) vegetative
B) disputes
IN ) sexual
D) budding
19. Reproduction carried out by the fusion of gametes is called
A) asexual
B) vegetative
IN) sexual
D) controversial
20 Parthenogenesis is characterized by
A) partial exchange of hereditary information through the cytoplasm
B) development of an embryo from an unfertilized egg
B) death of sperm after penetration into the egg
D) development of the egg due to the genetic material of sperm
21. Great value sexual reproduction for evolution is that
A) During fertilization, new combinations of genes may arise in the zygote
B) the daughter organism is an exact copy of the parent organisms
C) due to the process of mitosis, an embryo is formed from the zygote
D) the development of a new organism begins with the division of one cell
22. As a result of sexual reproduction in populations
A) various somatic mutations occur
B) the number of individuals of the species increases rapidly
C) the genotype identical to the maternal one is preserved
G) the genetic diversity of individuals in the population increases
23. Reproduction of humans, animals, plants, in which the fusion of two specialized cells occurs, is called
A) budding
B) parthenogenesis
B) asexual
G) sexual
24. Parthenogenesis is
A) reproduction by development of an adult from an unfertilized egg
B) reproduction of hermaphrodites that have both testes and ovaries
B) reproduction by budding
D) artificial fertilization of an egg (in vitro)
25. What type of reproduction is parthenogenesis?
A) sexually mu
B) vegetative
B) budding
D) asexual
26. In plants obtained by vegetative propagation
A) adaptation to new conditions increases
B) the set of genes is identical to the parent
B) combinative variability appears
D) many new signs appear
27. Which animal reproduces by budding?
A) white planaria
B) freshwater hydra
B) earthworm
D) big pond snail
28. What mushrooms reproduce by budding?
A) mukor
B) penicillium
IN) yeast
D) champignons
29. The exchange of hereditary information occurs in the process
A) sporulation of Escherichia coli
B) budding of freshwater hydra
C) vegetative propagation of strawberries
G) conjugation between individuals of ciliates-slippers
30. How does a fungal spore differ from a bacterial spore?
A) represented by only one cell
B) performs the function of reproduction
B) carried by the wind over a long distance
D) serves as an adaptation to unfavorable conditions
31 The basis of asexual reproduction of unicellular animals is
A) cyst formation
B) parthenogenesis
B) meiotic division
G) mitotic division
32. The sexual method includes reproduction
A) m honey bee parthenogenesis
B) freshwater hydra by budding
B) ciliates-slippers dividing in two
D) white planaria with body fragments
33. Parthenogenesis is a method of reproduction by
A) budding
B) regeneration
B) sporulation
G) sexual
34. Bacteria as opposed to fungi
A) do not reproduce by spores
B) form specialized germ cells
B) consist of a variety of tissues
D) have a cell wall
35. Sexual reproduction more progressive because it
A) provides a larger number of offspring compared to asexual
B) maintains the genetic stability of the species
IN) provides greater genetic diversity in offspring
D) inhibits excessive fertility of the species
36. Participates in asexual reproduction
A) moss spores
B) rat sperm
B) elephant eggs
D) mature human erythrocytes
37. Participate in sexual reproduction
A) blastomeres
B ) gametes
B) kidneys
D) disputes
Reproduction is one of the characteristic features of all living organisms, along with respiration, nutrition, movement and others. Its importance is difficult to overestimate, because it ensures the very existence of life on planet Earth.
In nature, this process is carried out in different ways. One of them is asexual vegetative reproduction. It is found mainly in plants. The importance of vegetative propagation and its varieties will be discussed in our publication.
What is asexual reproduction
The school biology course defines vegetative propagation of plants (grade 6, section “Botany”) as one of the asexual types. This means that germ cells are not involved in its implementation. And, accordingly, recombination of genetic information is impossible.
This is the most ancient method of reproduction, characteristic of plants, fungi, bacteria and some animals. Its essence lies in the formation of daughter individuals from maternal ones.
In addition to vegetative, there are other methods of asexual reproduction. The most primitive of them is cell division in two. This is how plants and bacteria reproduce.
A special form of asexual reproduction is the formation of spores. Horsetails, ferns, mosses and mosses reproduce in this way.
Asexual vegetative reproduction
Often with asexual reproduction, a new organism develops from a whole group of parent cells. This type of asexual reproduction is called vegetative.
Reproduction by parts of vegetative organs
The vegetative organs of plants are the shoot, consisting of a stem and a leaf, and the root, an underground organ. By splitting off their multicellular part or petiole, a person can carry out vegetative propagation.
What is cuttings for example? This is the method of the mentioned artificial vegetative propagation. So, in order to increase the number of currant or gooseberry bushes, you need to take part of their root system with buds, from which a shoot will be restored over time.
But stem petioles are suitable for propagating grapes. Of these, after some time the root system of the plant will be restored. A necessary condition is the presence of buds on any type of petiole.
But for the reproduction of many indoor plants leaves are often used. Surely, many people bred Uzambara violet in this way.
Reproduction by modified shoots
Many plants form modifications of vegetative organs that allow them to perform additional features. One of these functions is vegetative propagation. We will understand what special modifications of shoots are if we consider rhizomes, bulbs and tubers separately.
Rhizome
This part of the plant is located underground and resembles a root, but, despite the name, it is a modification of the shoot. It consists of elongated internodes from which adventitious roots and leaves extend.
Examples of plants that reproduce using rhizomes are lily of the valley, iris, and mint. Sometimes this organ can also be found in weeds. Everyone knows how difficult it can be to get rid of wheatgrass. When pulling it out of the ground, a person, as a rule, leaves parts of the overgrown wheatgrass rhizome underground. And after a certain time they sprout again. Therefore, in order to get rid of the said weed, it must be carefully dug up.
Bulb
Leeks, garlic, and narcissus also reproduce using underground modifications of shoots called bulbs. Their flat stem is called the bottom. It contains juicy, fleshy leaves that store nutrients and buds. They are the ones that give rise to new organisms. The bulb allows the plant to survive a difficult period for reproduction underground - drought or cold.
Tuber and mustache
To propagate potatoes, you do not need to sow seeds, although they produce flowers and fruits. This plant reproduces by underground modifications of shoots - tubers. To propagate potatoes, it is not even necessary that the tuber be whole. A fragment of it containing buds is enough, which will sprout underground, restoring the entire plant.
And strawberries and wild strawberries, after flowering and fruiting, form ground lashes (whiskers), on which new shoots appear. By the way, they should not be confused with the tendrils of grapes, for example. In this plant they perform another function - the ability to attach to a support for a more comfortable position in relation to the sun.
Fragmentation
Not only plants are able to reproduce by separating their multicellular parts. This phenomenon is also observed in animals. Fragmentation as vegetative propagation - what is it? This process is based on the ability of organisms to regenerate - restore lost or damaged body parts. For example, a whole individual, including integument and internal organs animal.
Budding
Budding is another method of reproduction, but vegetative buds have nothing to do with it. Its essence is as follows: a protrusion forms on the body of the mother’s body, it grows, acquires the features of an adult organism and splits off, beginning an independent existence.
This budding process occurs in freshwater hydra. But in other representatives of the coelenterates, the resulting protrusion does not break off, but remains on the mother’s body. As a result, bizarre reef shapes are formed.
Increase in quantity butter dough, which is prepared using yeast, by the way, is also the result of their vegetative propagation through budding.
The importance of vegetative propagation
As you can see, vegetative propagation in nature is quite widespread. This method leads to a rapid increase in the number of individuals of a certain species. Plants even have a number of adaptations for this, in the form of shoots.
Using artificial vegetative propagation (which this concept implies has already been said earlier), a person propagates plants that he uses in his economic activities. It does not require an individual of the opposite sex. And for the germination of young plants or the development of new individuals, the familiar conditions in which the mother’s organism lives are sufficient.
However, all varieties of asexual reproduction, including vegetative ones, have one feature. Its result is the emergence of genetically identical organisms that are an exact copy of the maternal one. To preserve the biological species and hereditary characteristics, this method of reproduction is ideal. But with variability, everything is much more complicated.
Asexual reproduction, in general, deprives organisms of the opportunity to develop new characteristics, and therefore one of the ways to adapt to changing environmental conditions. Therefore, most species in nature are capable of sexual intercourse.
Despite this significant drawback, when breeding cultivated plants, the most valuable and widely used is still vegetative propagation. A person is satisfied with this method due to the wide variety of possibilities, short periods of time, and the number of organisms that reproduce in the described way.
