Method of Plant Breeding in Self Pollinated Plants – Hybridization
Different type’s steps involved selection procedure after hybridization. Pedigree method, def pedigree record, procedure, merits and demerits.
Hybridization is one of the methods for developing new variety by crossing two lines or plants having unlike genetic constitution or it is the mating or crossing of two plants or lines of dissimilar genotype in order to combine desirable characters from both the parents.
The chief objective of hybridization is to create genetic variation. When two plants having unlike genetic constitution are crossed, the genes from both the parents are brought together. Segregation and recombination produce many new gene combinations in F2 and the subsequent generation. The degree of variation produced by hybridization in the segregating generation depends upon the number of heterozygous genes in the F1, and this depends upon the number of gene for which two parents differ.
The aim of hybridization may be transfer of one or few qualitative characters, the improvement in one or more quantitative character or the use of F1 as a hybrid variety. These objectives are grouped into two classes.
1) Combination Breeding:
The main aim of combination breeding is the transfer of one or more characters into a single variety, from other varieties. These characteristics may be governed by oligogenes or Polygenes.
2) Transgressive Breeding:
Transgressive breeding aims at improving yield or its contributing character through Transgressive segregation. Transgressive segregation is the production of plants in F2 generation that are superior to both the parents for one or more characters.