Protoplast of different species can be fused to generate a hybrid and this process is referred to as somatic hybridization
Protoplast are naked plant cells without the cell wall but they posses plasma membrane and all other cellular component.
Cybridization (Cytoplasmic Hybrid)
Cybridization is the phenomenon of fusion of normal protoplast with an enucleated (without nucleus) protoplast that results in the formation of a cybrid or cyoplast .
Term Protoplast – Hanstein -1880
First isolation of protoplast – Klercker 1892
Regeneration of Whole plant (Tobacco) prom protoplast first achieved by – Rakabe – 1971
Importance of protoplast culture
- The protoplast in culture can be regenerated in to a whole plant
- Hybrid can be developed from protoplast fusion
- It is easy to perform single cell cloning with protoplasts
- Genetic transformation can be achieved through genetic engineering of protoplst DNA
- Protoplast are excellent material for ultrastructure studies.
- Isolation of cell organelles and chromosomes is easy from protoplasts.
- Protoplasts are useful for membrane studies (transport and uptake processes)
- Isolation of muttants from protoplast cultures is easy.
Somatic Hybridization or protoplast fusion
Production of hybrid plants through the fusion of protoplasts of two different plant species or varieties is called somatic hybridization such hybrid is called somatic hybrid.
•The technique is used for hybridization between two different species and different genera where crosses are not possible by sexual reproduction.
•It is useful because hybrid cells of plants can be easily regenerated to whole plants due to totipotency
Somatic hybridization involves following four steps:.
•(i) Isolation of protoplasts
• (ii) Fusion of protoplasts of desired varieties or species
• (iii) Selection of somatic hybrid cells
•(iv) Culture of hybrid cells and regeneration of hybrid plant from them