The root performs the most important functions in the plant body. The main ones are fixation in the soil, absorption and conduction of water with substances dissolved in it, as well as vegetative propagation. The possibility of these processes is associated with structural features of various root systems.
What is the root?
The root is the underground organ of the plant. Although in nature there are its special varieties - respiratory, which are able to absorb moisture in the air. Depending on the structural features, several types of roots are distinguished: main, lateral and subordinate.
The first plant is always one. Side roots depart from it. Usually there are a lot of them, due to this the suction surface area increases. Roots that grow immediately from the shoot are called subordinate.
Types of Root Systems
But to ensure the whole variety of functions of an underground organ of one type, a plant organism is not enough. Therefore, they combine to form two types of root systems. The core consists of the main and side. Its main advantage is that plants with a stem system can get water deep from the ground.
The fibrous root system is formed only by subordinate roots that extend from the aerial part of the plant - the shoot. They grow in a large bunch, most of them have the same length.
The fibrous root system is characteristic of representatives of the Cereal (Bluegrass), Onion, and Lily families . All of them belong to the class Monocotyledonous.
Fibrous root system
Among the dicotyledons, a plantain has an underground organ of this type. The fibrous root system develops on modifications of the shoot. An example of this is a strawberry mustache or fern rhizome.
The fibrous root system is able to penetrate into the soil at a distance of up to two meters. There it grows quite wide in width.
From the beginning of development, the main root of this system begins to grow. However, it soon dies and is replaced by subordinate stem-species.
The length of the fibrous root system varies. In the vast majority of cereal plants, it reaches three meters, and in corn - up to ten. In some of the most valuable representatives of monocotyledons - wheat and rye - the bulk of the subordinate roots develop at a depth of several tens of centimeters. Therefore, such plants are very sensitive to lack of moisture.
But the fibrous root system has many advantages. Being at a shallow depth, it covers a much larger area of nutrition. For example, the total length of all wheat roots is about 20 km.
Plants with a fibrous root system
If drought is the worst enemy of cereals and their roots, then it is not terrible for plants of moist natural zones. After all, they, on the contrary, suffer from an overabundance of water. This can cause decay processes, which will inevitably lead to the death of plants. That is why they have a number of vital adaptations for development in this natural zone. These are leaves with a wide leaf blade, and a thin bark of trees. Of particular importance is the structure of the underground organ of tropical plants. A large number of accessory superficial roots ensures the rapid absorption of a sufficient amount of moisture. In an upward current, this water enters the leaves, which provide the transpiration process - evaporation of water from the surface of the plate.
The fibrous root system is characteristic of plants that have bulbs. They accumulate water with dissolved nutrients. Tulip, lily, leek, garlic use them as a stock. This helps them survive the adverse period.
Modifications and their functions
In the fibrous root system, modifications often occur. In this regard, additional functions appear. For example, the subordinate roots of dahlia, chistyak and sweet potato sweet potato, which is a popular crop of tropical countries, thicken and form tubers. They not only store nutrients and water, but also participate in vegetative propagation. The aerial roots of orchids are also secondary. They are able to absorb moisture directly from the air.
The fibrous root system is also characteristic of ivy. With its help, he clings to a support and grows up, bringing leaves to the light. Some plants of the tropics form subordinate roots directly on the trunks and branches. Growing to the ground, they serve as props for a wide crown. The same device has corn. Since the subordinate roots usually occupy a superficial position and are not able to hold the plant in the soil, peculiar supports perform this function.
Thus, the fibrous root system is characteristic of many plants and provides the most important functions of growth, nutrition and reproduction.