Morphology of root system

Morphology of root system

Roots are typically of non-green underground cylindrical structure forming the axis of the plant which gives rise to endogenous and does not possess leaves, nodes or buds.

Characteristics of the root system

  • They normally constituted the descending part of the plant axis.
  • These are the cylindrical structure which is non-green and do not have the distraction of nodes and internodes.
  • Buds and leaves are absent and its functions root is covered by a root cap.
  • Root branches develop from the interior of the parent root such and origin is called endogenous which is in contrast to exogenous or external origin in case of the stem.
  • The roots are neutral or negatively phototrophic and positively hydrotropic and positively geotropic.

Morphology of root system

 Parts of a typical root:

(1) Root cap:

  • It is our thimble-shaped or cap-like parenchymatous multicellular structure which covers the root meristem.
  • The cells of the root cap secret mucilage.
  • The water lubricates the passage of roots through the soil.
  • Without it, the tender route would be unable to penetrate the hard soil.
  • Another function of the root cap is the protection of the root meristem from the friction of the soil particle.
  • Route pockets function at balance in the aquatic plants which is finger glove-like covering at the root apices.
  • These are structurally similar to the root caps but differ from the damaged or lost root pocket are not regenerated.

(2) Growing point Or meristematic zone

  • It is about 1 mm in length.
  • The growing point of the root is determined and lies protected below the root cap.
  • The meristematic reason produces a new cell for the root cap and the based region of the root.
  • Therefore it is essential for the growth of the root.

(3) Region for the zone of elongation

  • It is about 4 to 8 mm in length.
  • It lies behind the growing point.
  • The cells of this region are newly formed cell which loses the power of division.
  • They elongate rapidly.
  • This increase the length of the root.
  • This also causes the power of absorption of water and mineral salt from the soil.

(4) Root hair zone

  • It also represents the zone of differentiation or maturation because a different type of primary tissues differentiates or mature in this reason like xylem and phloem, pericycle, endodermis cortex, epiblema etc.
  • Root hair zone is 126 CM in length.
  • Most of the water absorption occurs in this region.
  • Some of the outer cells of this zone give rise to lateral tabular outgrowth called root hairs.
  • The root hairs increase the exposed surface of the root for absorption.

(5) Region or zone of mature cell

  • It forms the bulk of the route.
  • The cells of this reason do not undergo any further change.
  • The outermost layer of this region has a thick world or impermeable sales.
  • So this region cannot help the root in water absorption.
  • Its only functions to anchor the plant firmly in the soil.

Types of the root system

  • There are two types of root system tap and adventitious.

(1)Taproot system:

  • it is a mass of roots which develop from the radicle of the embryo.
  • it consists of a tap root, secondary roots, tertiary roots and also rootlets.
  • The radical itself grow up directly into the main or primary root.
  • The persistent primary root is known as the taproot.
  • they are formed in acropetal succession and oldest towards the base of the parent Root.
  • Rootlets are the ultimate root branches.
  • They bear root hair for absorption.
  • The root system is of two types:-

(1)Deep feeder

(2)Surface feeder

  • deep feeder tap root which penetrates the deeper layer of the soil.
  • it is mostly found in trees.
  • in surface feeders, the taproot does not elongate very much.
  • the secondary roots spread to a greater extent mostly horizontal near the soil surface.
  • the surface feeder tap root system of some annual plant consists of thin fibrous roots.
  • it may be called a fibrous tap root system.

(2) adventitious root system

  • The root that grows from any part of the plant other than the radicle or its branches is called adventitious roots.
  • The branches like a taproot.
  • a mass of adventitious roots along with their branches constituent and adventitious root system.
  • the plant having adventitious root also developed primary root from the radical.
  • However, it is short-lived and therefore does not produce taproot.
  • fibrous roots are underground root which arises in group weather at the base of the erect steam for the notes of the horizontal stem.
  • the main roots are of equal length.
  • they give off small branches.
  • both the main root and their branches are thin and thread-like.
  • therefore they are called fibrous roots which do not penetrate deep in the soil are hens named as a surface feeder.

Function of roots

Primary or main functions

  • Anchorage:-

Roots take part in a succession of the plant and supporting the aerial shoot system.

  • Absorption of water

Roots absorb water from the soil.

  • absorption of minerals

Roots absorb mineral salts from the soil.

  • production of soil erosion

Roots hold the soil particles firmly to prevent soil erosion.

  • Transport

The taking part in transport to absorb water and mineral to shoot system.

Secondary functions:

  1. Storage: It occurs in fresh roots.Conical-carrots, Napiform-Beat, Tuber-microbilis
  2. Extra or mechanical support: It is provided by several types of roots.Buttress roots- Bombax,Stilt roots- Maize
  3. Climbing: Roots help some of the weak stem plants to cling and hence climb of support.Ex- money plant.
  4. Nitrogen fixation: Nodulated roots of pea, bean, gram, methylation: Prop roots, knee roots
  5. Reproduction: By bearing adventitious buds on both tap roots and adventitious roots.
  6. Floating: By storing air sum of the function of the root as floats.
  7. Photosynthesis: As in propa, Tinospora
  8. Oxidation: The roots of some amphibious plant release Oxygen and oxidize the surrounding environment as for example rice.

Also, you can check the flowering plant characteristics and reproduction in-Study Notes on Sexual reproduction in flowering plants