Roots are the important parts of the plant and trees. They help in
- fixing the plant firmly to the soil,
- provide water,
- provide minerals and manures,
- storage of food,
- excretion of waste,
- source of vital medicine and drugs,
- source of fiber,
- help in Plant propagation,
- supports the life of other organisms.
Plant fixation: Plants are the organisms which do not move in their lifetime. They grow and die in the same place where they are born. This ability to stay at one place is due to their root system. These roots fix the plants and trees firmly in the ground. Even heavy winds, flood also would not be able to uproot the plants. Such is the strength of roots in fixing the whole plant in soil.
Provide water: Plants require a continuous supply of water. This is necessary to move the sap in the plant from bottom to top. To manage the body temperature of the plant etc. This water is supplied by the roots system by capillary action.
The roots keep on growing through the entire life of the plant to different regions below the ground in search of water for the plant. So sometimes they grow to a few meters if needed.
Provide minerals and manure. Besides water, roots also supply manures, minerals from the soil to the plants. These are essential for plant growth and physiology. Minerals include macro and microelements. Manures include ammonia, nitrogen, etc.
Storage of food: Roots also act to store the food material of plants.
For example in plants like carrot, radish, onion, groundnut etc, the food is stored in roots. This food is meant for future consumption by the same plant. But animals and human can feed on these stored food roots.
Waste expulsion: Roots also help to expel the waste from plant body. Accumulation of this waste could be toxic to the plant.
Help in Plant propagation: Roots of some plants help to produce a new plant from the root cutting. Plants like raspberry, rose, blackberry, phlox , lilac, fig, trumpet vine,etc. can be grown by roots. A 2 to 6 inch long root cutting is stored in suitable conditions for 3 weeks and then transferred into soil. These grow into new plants. See the method to grow plant from root cuttings.
Uses of roots to man:
Source of vital medicine and drugs: Roots are some of the important sources of life-saving medicines. Plant medicines like Rauwolfia, ipecac, ginseng, ashwagandha etc. are obtained from the roots.
Source of fiber: Like leaves, the fiber from roots is used as brooms, brushes, baskets etc. Examples of these plants include Zacaton
Supports life of other organisms. Many microbes and even other plant live on the roots. They derive nutrition and other essentials from roots. Some of them microbes even help the plant in return. Example of such bacteria is rhizobium bacteria. This is a bacteria which is present in the roots of leguminous plants. These bacteria help fix the nitrogen from air as ammonia in soil. Thus they provide manure to the plant. In return, they obtained food and shelter from the plant. This is called a symbiotic relationship.