Describe the tissue culture technique in plants.

Explanation

Plant tissue culture is an advanced technique of plant breeding that developed around the 1950s. Plant tissue culture makes use of parts of a plant to generate multiple copies of the plant in a very short duration. The technique is based on the property of totipotency of plant cell which means that any cell from any part of the plant can be used to generate a whole new plant.
Types of Plant tissue culture :
(i) Seed Culture
(ii) Embryo Culture
(iii) Callus Culture
(iv) Organ Culture
(v) Protoplast Culture
(vi) Anther Culture
An example of use of plant tissue culture in the lab :
Step 1: A new gene of interest is introduced into tissue of a plant. Thus altering its genotype.
Step 2: The transformed plant cells are then isolated and placed into sterile nutrient agar.
Step 3 : Each cell grows into a cluster of cells called a callus.
Step 4: Calluses are separated and a plant hormone called cytokinin is added which stimulates growth of small leaf shoots.
Step 5: Shoots are separated and the addition of another plant hormone called auxin stimulates the growth of roots.
Step 6: New plants are transferred to soil and grown to observe how the alteration of its genotype has affected its phenotype under extreme environmental conditions such as high salt, increased CO2 and drought.

Tissue culture is used to develop thousands of genetically identical plants from one single parent plant known as soma clones, and this process is known as micro-propagation. The method offers an advantage over other methods as it can be used to develop disease free plants from disease-rode plants by using their meristems (apical and axillary) as explants.