Question

Choose the correct option with respect to somatic hybridization.

(i) Protoplasts of different cells of the same plant are fused.

(ii) Protoplasts from cells of different species can be fused.

(iii) Cells are treated with cellulase and pectinase for protoplasm isolation.

• A. Only i is incorrect
• B. Both i and ii are incorrect
• C. Only iii is incorrect
• D. Both i and iii are correct

Answer 1

The correct option is A Only i is incorrect

Somatic hybridization is a technique of formation of hybrids through protoplast fusion in plants. Protoplasm fusion can be carried out between cells of different species or different varieties of same species. Hence statement ii is correct and statement i is incorrect.

Somatic hybridization is carried out as follows:
i) Cell wall removal - The plant cells lacking cell wall are called protoplasts. The cell walls of the cells of selected parents are digested with a combination of enzymes like pectinase and cellulase. Hence statement iii is correct.

ii) Fusion of protoplasm - Fusion between protoplasts of the selected parents is induced by a solution of polyethylene glycol (PEG) or high voltage electric current. Fusion of protoplasts involves the fusion of their cytoplasm and nuclei.

iii) Formation of cell wall - The fused protoplasts are allowed to grow on culture medium. Regeneration of cell wall in fused protoplast is induced by hormones.

iv) Callus formation - Cells grow into callus which give rise to plantlets.

Figure : Somatic hybridization

For example, Pomato is a somatic hybrid between potato and tomato.