It is difficult to overestimate the importance of the underground organ of plants. After all, it reliably holds even huge trees in the soil, provides them with water and a sufficient supply of nutrients. Sometimes environmental conditions require additional functions to be performed. And then the root is modified.
Root and its structure
According to the structural features, several types of roots are distinguished. The main root acts as a pivot. It is easy to distinguish it from others. A plant has only one. Lateral branches depart from the main root. They are needed to increase the surface area of the soil in order to be able to absorb more moisture. The root system, consisting of such roots, is called the pivot. Roots that grow directly from the shoot (above-ground part of the plant) are called adventitious. Their bundle forms a fibrous root system.
Modifications of plant roots
The classical structure of the root system makes it possible to perform only certain functions. In order for plants to survive in difficult conditions, it is necessaryroot modification. Let's consider each of them in more detail.
Root crops
Everyone remembers the fairy tale about tops and roots. Such a modification of the root, like root vegetables, is an example of tasty and juicy roots. Carrots, radishes, turnips, beets… It is impossible to imagine one day without the presence of these he althy and tasty foods in our diet.
They are the result of thickening of the main root of the rod system. In order to survive the cold autumn and winter and form seeds, the plant stores water with minerals underground. And a person uses juicy root vegetables for food.
Root tubers
What is a modification of the root can also be considered on the example of root tubers. This is also a thickening of the roots. But not the main one, but the adventitious roots of the fibrous system. As a result, the underground beam becomes powerful and heavy due to a significant supply of water. It is found in dahlia, asparagus, cinquefoil, sweet potato.
An additional function of root tubers is vegetative reproduction. It is possible due to the presence of adnexal buds on these modifications, which are often also called root cones.
Aerial roots
Growth conditions and modifications of the roots are inextricably linked. Plants of equatorial forests grow in conditions of high humidity. Such plants do not need to get moisture from the soil, since there is enough of it in the air. For example, an orchid grows directly on tree trunks from which aerial roots hang. Absorbing water directly from the air, they provide the plant with this essential substance with the help of aerial (respiratory) roots. Ficus, fat woman, monstera are indoor plants that also form aerial roots. For their normal development, sufficient humidification of the air in the room is necessary.
Support Roots
A support root is also a modification of the root. The name itself speaks of the functions it performs. Indeed, strong adventitious roots, like an artificial mount, hold the shoot. They are often seen in corn. The shoot of this plant with fruits is quite weighty. And the fibrous root system has rather superficial roots that are not able to hold the plant during strong gusts of wind. Here a special device comes to the rescue - prop roots.
Many have seen a man on stilts in the circus, but in nature you can find plants on such devices. Stilted roots are like props, but grow from the shoot down. In mangroves of tropical forests, they additionally perform the function of absorbing moisture from the air. They seem to lift the plants of the tide zone above the water, ensuring their normal functioning.
Trailer Roots
The well-known ivy is able to occupy any surface. Even a vertical rock will not be a special obstacle for him. Suchhe acquired the ability due to the presence of adventitious trailing roots that can attach to any surface.
Gaustoria
In parasitic plants, a modification of the root is a haustoria or sucker root. The beautiful rafflesia, which has a very large flower, is incapable of photosynthesis. Therefore, it cannot provide itself with organic substances. Where can you get them? Of course, in another plant. With the help of suckers, rafflesia penetrates the roots and stems of tropical vines, sucking out ready-made substances from them. Surprisingly, this plant consists only of modified roots and a giant flower.
There are also semi-parasitic plants. For example, mistletoe is capable of photosynthesis and produces the required amount of sugars on its own. But water and nutrients dissolved in it are obtained not from the soil, but from other plants with the help of sucker roots.
Mycorrhiza
Everyone knows that the boletus grows under the birch, and the boletus grows under the aspen. But not everyone understands why this is so. The fact is that the roots of some plants cohabitate mutually with fungi. From such a symbiosis is good for everyone. Mushrooms receive organic substances from a tree, which they cannot produce on their own, since they are incapable of photosynthesis. And trees with the help of fungi are provided with water with a solution of inorganic substances.
Changing the root helps the plant survive in conditions of deficiency or excess of moisture, better hold in the soil, attach to a support and remain viable for a long time, giving a wonderful harvest.
Man has long learneduse them in your work. Root crops containing a large amount of valuable vitamins and minerals are used as food. And not only in raw, but also in boiled, fried and canned form. Forage varieties of beets and turnips are grown for livestock. Sugar is obtained from a special type of beet by processing. But in parsley, it is not the bitter root that is valued, but the juicy and healing leaves of the shoot. So, changing, the roots benefit not only plant, but also animal organisms and humans.
