INTRODUCTION TO CASPARIAN STRIPS IN PLANT ROOTS
Plants grow in soil and anchor to the soil through roots. The roots of plants absorb water and other important nutrients from the soil. They also need to avoid the absorption of toxic materials. To avoid this unusual absorption, plants have developed Casparian strips in their endodermal and epidermal layer of cell walls of roots. Plant cell walls also contain other chemicals such as cellulose, lipids, waxes, proteins, carbohydrates and other polysaccharides. Due to hydrophobic nature of Casparian strips, they are much useful for plants.
Casparian strips are a single layer of sclerenchymatous cells. They are found in plant roots and act as a chemical diffusion barrier. They help in the diffusion of useful materials and avoid the entrance of toxic solutes. Casparian strips were discovered in 1965 by a German botanist Robert Caspary and named after his name. It is quite unnatural in the history of botany that discovery was named after the name of the scientist who discovered it. Casparian strips are specific for each type of tissue.
Casparian strips contain different chemicals like;
- Other cell wall proteins
Casparian strips are found in;
- The cell wall of the plant
- Root of plant
How Casparian Strips Are Developed?
In the plant roots, Casparian strips are developed via different methods.
In the primary stage during endodermis development, lipophilic and aromatic are deposited in transverse and radial walls to make Casparian strips.
- In the secondary stage, the middle lamella is deposited in the protoplast next to anticlinal and tangential cell walls.
- In the tertiary stage, Casparian strips are formed by deposition of cellulose in radial, tangential and transverse walls.
- Casparian strips prevent the uptake of ions during different environmental changes.
- They act as an apoplastic transport barrier in roots.
- They act as a diffusion barrier and allow only some substances to pass through