The root performs the most important functions in the plant organism. 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 implementing these processes is associated with the structural features of various root systems.
What is a root?
The root is called the underground organ of the plant. Although in nature there are its special varieties - respiratory ones, which are able to absorb moisture in the air. Depending on the structural features, several types of roots are distinguished: main, lateral and adnexal.
The first plant is always alone. It has lateral roots. Usually there are quite a lot of them, due to this, the area of \u200b\u200bthe suction surface increases. Roots that grow immediately from the shoot are called adventitious.
Types of root systems
But to provide the whole variety of functions of an underground organ of one type, a plant organism is not enough. Therefore theycombine to form two types of root systems. The core consists of the main and side. Its main advantage is that plants with a rod system can get water from deep underground.
The fibrous root system is formed only by adventitious 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.
Fibrous root system is typical for representatives of the Cereal (Poa), Onion, Liliaceae families. All of them belong to the class Monocots.
Fibrous root system
Among the dicots, this type of underground organ is found in the plantain. The fibrous root system develops on modifications of the shoot. An example of this would be strawberry whiskers or fern rhizomes.
The fibrous root system is able to penetrate deep into the soil at a distance of up to two meters. There it grows quite strongly in width.
From the beginning of development, the main root of this system begins to grow. However, it soon dies off and is replaced by adventitious stem-like 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 monocots - wheat and rye - the bulk of adventitious roots develop at a depth of up to several tens of centimeters. Therefore, these plants are very sensitive tolack of moisture.
But the fibrous root system has a lot of advantages. Being at a shallow depth, it covers a much larger feeding area. For example, the total length of all wheat roots is about 20 km.
Plants with fibrous root system
If drought is the worst enemy of cereals and their roots, then it is not terrible for plants in wet natural areas. After all, they, on the contrary, suffer from an excess of water. This can cause rotting 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 area. These are leaves with a wide leaf blade, and thin bark of trees. Of particular importance is the structure of the underground organ of tropical plants. A large number of adventitious superficial roots ensures the rapid absorption of a sufficient amount of moisture. Through the ascending current, this water enters the leaves, which provide the process of transpiration - the evaporation of water from the surface of the plate.
Fibrous root system is typical for plants that have bulbs. They store water and dissolved nutrients. Tulip, lily, leek, garlic use them as a stock. This helps them get through the bad times.
Modifications and their functions
Modifications often occur in the fibrous root system. In this regard, additional functions appear. For example, the adventitious roots of dahlia, chistyak and sweet potato yam, which ispopular culture of tropical countries, thicken and form tubers. They not only store nutrients and water, but also participate in vegetative propagation. Orchid aerial roots are also adventitious. 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 the leaves to the light. Some plants of the tropics form adventitious roots directly on the trunks and branches. Growing to the ground, they act as supports for a wide crown. Corn has the same adaptation. Since adventitious roots usually occupy a superficial position and are not able to hold the plant in the soil, this function is performed by a kind of props.
Thus, the fibrous root system is characteristic of many plants and provides the most important functions of growth, nutrition and reproduction.
