Reproduction is one of the characteristic features of all living organisms along with breathing, nutrition, movement and others. Its value can hardly be overestimated, because it ensures the continuity of generations, and hence the very existence of life on planet Earth.
In nature, this process is carried out in various ways. One of them is asexual vegetative propagation. It occurs mainly in plants. The significance of vegetative propagation and its varieties will be considered in our publication.
What is asexual reproduction
A school biology course defines the vegetative propagation of plants (grade 6, section "Botany") as one of the types of asexual. This means that during its implementation, germ cells are not involved. And, accordingly, the recombination of genetic information is impossible.
This is the oldest method of reproduction, characteristic of plants, fungi, bacteria and some animals. Its essence lies in the formation of maternal daughter individuals.
In addition to vegetative, there are other ways of asexual reproduction. The most primitive of these is cell division in two. So unicellular animals and plants multiply, as well as bacteria.
Another variation of this method is multiple division. It consists in the fact that several daughter cells are simultaneously formed from one mother cell. This happens, for example, in malarial plasmodium, which parasitizes in blood cells.
A special form of asexual reproduction is the formation of spores. Horsetails, ferns, mosses and moths reproduce in this way.
Asexual vegetative propagation
Often with asexual reproduction, a new organism develops from a whole group of parent cells. This kind of asexual reproduction is called vegetative.
Next, we describe the types and examples of organisms that are characterized by vegetative propagation. A table listing them will help to make a general idea of the prevalence of this type of reproduction.
| Type of vegetative propagation | Organism example |
| Parts of vegetative organs | Algae - parts of the thallus, garlic - onions, currants - cuttings |
| Fragmentation | Earthworm, molds, spirogyra green alga |
| Budding | Freshwater Hydra, Coral Polyps, Yeast Mushrooms |
Reproduction by parts of vegetative organs
The vegetative organs of plants are the shoot, consisting of a stem and leaf, and the root is 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 said artificial vegetative propagation. So, to increase the number of shrubs of currants or gooseberries, you need to take part of their root system with buds, from which the shoot will recover over time.
But for the reproduction of grapes stem stalks are suitable. Of these, after some time, the root system of the plant is restored. A prerequisite is the presence of kidneys on any type of petiole.
But for the propagation of many indoor plants often use leaves. Surely, many bred Uzambara violet in this way.
Propagation by modified shoots
Many plants form modifications of the vegetative organs, which allow them to perform additional functions. One of these functions is vegetative propagation. What are special modifications of shoots, we will understand if we consider separately rhizomes, bulbs and tubers.
Rhizome
This part of the plant is located underground and resembles the root, but, despite the name, is a modification of the shoot. It consists of elongated internodes, from which the adventitious roots and leaves depart.
Examples of plants propagated by rhizomes are lily of the valley, iris, mint. Sometimes the named organ can be found in weeds. Everyone knows how difficult it is to get rid of wheatgrass. Pulling it out of the ground, a person, as a rule, leaves parts of an expanded rhizome of wheatgrass under the ground. And after a certain time they germinate again. Therefore, in order to get rid of the named weed, it must be carefully scooped up.
Bulb
Leek, garlic, daffodil also reproduce with the help of podzimnyh modifications of shoots, which are called bulbs. Their flat stalk is called the base. On it are succulent, fleshy leaves storing nutrients and buds. They give rise to new organisms. The bulb allows the plant to survive underground a difficult period for reproduction - drought or cold.
Tuber and mustache
To propagate potatoes, you do not need to sow seeds, despite the fact that it forms flowers and fruits. This plant is propagated by underground modifications of shoots - tubers. To propagate potatoes, it is not even necessary for the tuber to be whole. Enough of its fragment containing buds, which will grow underground, restoring the entire plant.
After flowering and fruiting, strawberries and strawberries form ground lashes (mustaches), 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 gain a foothold on a support, for a more convenient position in relation to the sun.
Fragmentation
Not only plants are able to reproduce by separating their multicellular parts. This phenomenon is observed in animals. Fragmentation as vegetative propagation - what is it? This process is based on the ability of organisms to regenerate - to restore lost or damaged parts of the body. For example, an entire individual, including the integument and internal organs of an animal, can recover from a part of the body of an earthworm.
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 is split off, starting an independent existence.
This process of budding occurs in freshwater hydra. But in other representatives of the intestinal cavity - coral polyps - the resulting protrusion does not split off, but remains on the mother's body. As a result, bizarre forms of reefs form.
The increase in the number of pastry, which is prepared using yeast, by the way, is also the result of their vegetative propagation, by budding.
The value of vegetative propagation
As you can see, vegetative propagation in nature is widespread enough. This method leads to a rapid increase in the number of individuals of a particular species. In plants, for this, there are even a number of adaptations, in the form of modifications of the root and shoot.
Using artificial vegetative propagation (which such a concept suggests has been said before), a person propagates plants that he uses in his economic activities. For him, an individual of the opposite sex is not required. And for the germination of young plants or the development of new individuals, the familiar conditions in which the maternal organism lives are sufficient.
However, all varieties of asexual reproduction, including vegetative, have one feature. Its result is the appearance of genetically identical organisms, which are an exact copy of the mother. To preserve the biological species and hereditary features, this method of reproduction is ideal. But with volatility, things are much more complicated.
Asexual reproduction, on the whole, deprives organisms of the possibility of the appearance of new traits, and therefore of one of the ways of adaptation to changing environmental conditions. Therefore, most species in wildlife are also capable of sexual process.
Despite this significant drawback, when breeding cultivated plants, the most valuable and widely used is still vegetative propagation. This method suits a person because of a wide variety of possibilities, short in terms of duration, and the number of organisms that reproduce in the described way.