How is the tissue culture technique carried out ?

Step 1 :

·         Small pieces of a plant’s leaf, shoot, bud, stem, or root tissues are cut out.

·         These cut out plant tissues are called explants.

Step 2 :

·         Alternatively, enzymes are used to digest the cell walls of tissues, for example, the mesophyll tissue from a leaf.

·         This results in naked cells without cell walls called protoplasts.

Step 3 :

·         The explants or protoplasts are sterilized and then placed in a glass container which contains a nutrient solution with a fixed chemical composition. A culture medium or growth medium normally consists of a complex mixture of glucose, amino acids, minerals, and other substances required for the growth of the tissues.

·         The culture medium and the apparatus used must be in sterile conditions and free from microorganisms which can contaminate the tissue culture.

·         The pH and temperature of the culture medium also need to be maintained at optimum levels .

                       

Step 4 :

·         The explants or protoplasts begin to divide by mitosis.

·         Cell division produces aggregates of cells.

·         The aggregate of cells develop into a callus; an undifferentiated mass of tissue.

Step 5

·         The callus develops into a somatic embryo.

·         The embryo develops into a plantlet which can later be transferred to the soil for growth into an adult plant.

·         All the plantlets produced this way are genetically identical. Therefore, all the adult plants that develop from them share the same traits.