What are the different types of hybridization?

Explanation

According to the relationship between plants hybridization is divided into.
(i) Intravarietal hybridization - The cross between the plants of same variety. Such crosses are useful only in the self-pollinated crops.
(ii) Intervarietal hybridization - The cross between the plants belonging to two different varieties of the same species and is also known as intraspecific hybridization. This technique has been the basis of improving self-pollinated as well as cross pollinated crops.
(iii) Interspecific hybridization - The cross between the plants belonging to different species belonging to the same genus is also called intragenic hybridization. It is commonly used for transferring the genes of disease, insect, pest and drought resistance from one species to another.
Example: Gossypium hirsutum x
Gossypium arboreum.
(iv) Intergeneric hybridization - The crosses are made between the plants belonging to two different genera. The disadvantages are hybrid sterility, time consuming and expensive procedure.
Example: Raphanobrassica, Triticale.