One of the crucial part of the the vascular plant, that normally grows underground and nourish, and support plants in various ways to grow. The roots are the non-leafy part of a plants, and does not have any nodes.
Roots can also grow above the ground surface i.e. known as aerial or if they float over the surface of the water they are known as aerated. The root has four major parts, namely – Root Cap; The meristematic region; The region of elongation and The region of maturation.
Being the part of a plant, roots play various functions like, It gives anchor and support , photosynthesis, transportation of nutrients, storage, aeration, movement, reproduction, conduction and absorption.
It is important to know that the first part that appear when the seed germinates is the radicle or primary root. It starts growing toward the ground i.e in downward direction, therefore anchoring the seedling.
In monocotyledons and Grasses (angiosperms with a single seed leaf) consist of the fibrous roots system, having the bulk of roots with equal diameter. There is no network of roots found in this type.
On the other side, Dicotyledons, (angiosperms and gymnosperms with two seed leaves), the primary root or radicle becomes the tap root and thus growing downward followed by the growth of numerous secondary roots from the it (tap root). This type of system is seen in turnips, carrots.
Types of Roots
Found in dicots plants, where the single primary root give rise to numerous secondary and tertiary roots. The branches of the roots are in acropetal succession,where the new and short roots are formed at the apex or top of the primary roots, while the oldest ones are found at the base of the lead root.
Characteristics of tap roots
- Taproots appears from the radical of embryo.
- Primary roots is always present, till the life of a plant.
- As the penetration is high into the soil, they provide strong anchorage to the plants. However, unable to penetrate into the hard soil.
- Cocoa, okra, papayas, coffee, cotton , mustard, beetroot, parsley, china rose are the few examples.
Found in monocots, where the root is branched, slender and grows with the connecting parent stem. Such roots spread horizontally and grow close to the surface.
- Fibrous roots are underground and appears from the base of the stem.
- Cluster like appearance, consisting of numerous roots together having similar size.
- The primary roots gives rise to numbers of roots, thus replaced by the newer ones (adventitious roots).
- Does not penetrate into the deep soil.
- Rice, banana, maize, wheat and other monocots have this type of root system.
Adventitious roots show similarities with the fibrous roots, though they can be aerial (above the ground) or underground. The roots can be thick or thin or they can be modified according to the plant species. These roots can appear from stem nodes, leaves, intermodal, but not from radical .
- Adventitious roots usually grow under the stress condition or the place of waterlogging after floods.
- Adventitious roots also arise from the branch cuttings, leaf cuttings or in case of plant injury, this is due to increase the chances of plant survival and thus assisting it (plant).
- Bamboo, maize, mangrove, maize, rice are the few examples.
Creeping roots is generally seen in trees, where the growth of the roots is not underground, instead roots are shallow and spread horizontally long way, exactly from the base of th plant.
- Creeping roots cover the large portion of an area, where the trees grow.
- These roots does not penetrate deep into the soil, and generally goes long way, from the base of the plant.