A tuber is a part of a plant, which is its modified organ. It is necessary for the body to perform additional functions. Features of its structure and varieties of tubers of various origin will be discussed in detail in this article.
Modification Purpose
The underground and aboveground organs of plants are, respectively, the root and shoot. These vegetative parts serve for air and soil nutrition, as well as for asexual reproduction. But under certain conditions, additional functions are needed for the process of adaptation and increased vitality. For these purposes and need modifications. A tuber is a prime example of one of them.
A good example of a modification of the underground organ of plants is root crops. They are formed in carrots, beets, radishes, radishes. This is the thickening of the main root, which stores water and nutrients. Man uses them for food and as fodder crops.
Escape Modifications
Tuber and rhizome are modifications of the aerial organs. There is nothing surprising in this. Despite the location underground, in their structure they have all parts of the shoot. Examples are tubers, bulbs, rhizomes, tendrils, and mustaches. Each of them has its own structural features that determine their functions. For example, strawberry mustache is necessary for the vegetative propagation of this plant. Despite the fact that it forms flowers and seeds, this method is the most significant. But the grape's mustache is needed to attach its lashes to the support.
The leek or garlic bulb consists of a flat stem called the stem. Associated roots are attached to it . They grow in a bunch. This is a typical structure for a fibrous root system. At the bottom there are also buds and several types of leaves. Some of them are juicy and fleshy. They store water and nutrients. Other dry and dense, providing additional protection against mechanical damage and excessive transpiration. From buds located on the bottom, young green leaves periodically grow. They are called green onions. All of the listed features of the structure once again prove that the bulb is a modification of the shoot.
Tuber structure
The next example of a modification of the aerial organs is a tuber. It is characteristic of potatoes, Jerusalem artichoke, kohlrabi. A tuber is the result of thickening of the internodes of the stem, which can be either sub- or elevated.
Its base is a thickened stalk rich in starch and other substances. From adverse environmental conditions, it is protected by bark. We clean it when we use potatoes for cooking. On the thickened stem tuber of the potato are the kidneys. They are called eyes. With their help, the vegetative propagation of this plant is carried out. In the spring, young shoots appear from the buds, which form a bush and new tubers.
Root tuber
Not only shoots are able to form tubers. The underground part of the plant is no exception. So, the root tuber is characteristic of dahlia, sweet potato and chistyak. It is nothing more than a thickening of the accessory components of the fibrous root system. Despite the different origin and location, such modifications perform exactly the same functions.
Functions
The main purpose of both stem and root tubers is to store water with nutrient mineral and organic substances dissolved in it. Everyone knows how potato is rich in starch. It is in its tubers, in the cells of the storage main tissue, that the plastids of leukoplasts containing carbohydrates are located. In this form, plants with these changes easily endure adverse conditions, surviving them underground.
Another important function of this modification is the implementation of vegetative propagation. To grow potatoes, it is enough to cut the tuber into several parts, each of which must have kidneys - eyes, and plant them in the ground. This plant has fruits that can form seeds. But their number is small. Since potatoes are of great economic importance, breeders have attempted to develop new varieties with a large number of seeds. But the vegetative method of propagation using tubers was more productive.
Since a tuber is a storehouse of nutrients, such mutated elements are used as food. And Jerusalem artichoke is able to reduce blood glucose levels with constant use. Doctors recommend it to people with diabetes. The use of potatoes provides the body not only with the necessary daily content of carbohydrates, but also with valuable trace elements, for example, phosphorus and potassium.
Thus, tubers are modifications of the shoot or root and serve for the supply of nutrients, vegetative propagation. They have important food and household value.