What is somatic hybridization? Write it's advantage and disadvantages.

 

Questions 1. What is somatic hybridization? Write it's advantage and disadvantages.

Ans:- somatic hybridization :- fusion of isolated protoplast of two different plant species/varieties in vitro to form a hybrid cell and it's subsequent development to form hybrid plant is called somatic hybridization.

Somatic hybridization involves following steps:-

A. Agglutination (Adhesion):- when two protoplasts are in close contact with each other, adhesion occurs. Adhesion is induced by fusogen e.g. PEG, sodium nitrate, high pH and high Ca++

B. Plasma membrane fusion:- protoplast membrane get fused at localized sites at the point of adhesion.This leads to the formation of cytoplasmic bridge between protoplasts.

C. Formation of Heterokaryons :- the fused protoplast get rounded as a result of cytoplasmic Bridge bleeding to the formation of asherical heterokarons i.e. cell with two different nucleus.

D. Identification and selection of somatic hybrid cells.

E. Culture of the hybrid cells.

F. Regeneration of hybrid plants.

# Advantage of somatic hybridization

1. Production of heterozygous lines in the single species which can not be propagated by vegetative means.

2. Disease resistance genes from one plant is transfered to many others with the help of somatic hybridization.

3. Desirable characters can be introduced in hybrid plants.

4. It is used to overcome the limitations of sexual hybridization such as incompatibility barriers.

# Disadvantage of somatic hybridization

1. The plant produced are not always viable and fertile.

2. Protoplast fusion sometime brings genetic instability.