Question

(c) Briefly explain the various steps of tissue culture.
Ans.​

Answer 1

Explanation:

Plant tissue culture is an in-vitro culture of plant cells, tissues or organs which will form a complete plant.

Plant tissue culture works on the basis of totipotency. It is the ability of a plant cell to form the complete plant through dedifferentiation and redifferentiation.

It involves following steps:

1. Selection of plant- The plant which has to be cultured in vitro is selected.

2. Isolation of explant- Explant is any part of plant excised out for tissue culture.

3. Sterilization of explant- Explant is surface sterilized so as to avoid contamination.

4. Inoculation of explant- The explant is inoculated on the nutrient medium. For plant tissue culture, the most common medium used is MS media.

5. Incubation: After inoculation, the cultures are incubated so as to provide proper conditions for their growth and regeneration like temperature, moisture etc.

6. Initiation of callus: Callus is a mass of undifferentiated cells formed by the dedifferentiation of plant cells or the explant. Callus further regenerates to form roots and shoots and eventually the complete plant.

7. Sub-culturing: The cultured cells or tissues are transferred regularly to new nutrient medium and this is called subculturing.

8. Regeneration: Regeneration is the formation of organized structures like roots, shoots, flower buds etc from the cultured cells

9. Hardening: The plantlets are removed from the cultures and prepared for soil transfer and this transfer to fields is known as hardening.

Answer 2

Describe the various steps involved in tissue culture.

1) Selection of plant:

• The plant which has to be cultured in vitro is selected.

2) Isolation of explant:

• Explant is any part of plant excised out for tissue culture.

3) Sterilization of explant:

• Explant is surface sterilized so as to avoid contamination.

4) Inoculation of explant:

• The explant is inoculated on the nutrient medium.

5) Incubation:

• After inoculation, the cultures are incubated so as to provide proper conditions for their growth & regeneration like temperature, moisture etc.

6) Initiation of callus:

• Callus is a mass of undifferentiated cells formed by the dedifferentiation of plant cells or the explant.
• Callus further regenerates to form roots & shoots & eventually the complete plant.

7) Sub-culturing:

• The cultured cells or tissues are transferred regularly to new nutrient medium called subculturing.

8) Regeneration:

• Regeneration is the formation of organized structures like roots, shoots, flower buds etc from the cultured cells

9) Hardening:

• The plantlets are removed from the cultures and prepared for soil transfer & this transfer to fields is known as hardening.