Principles of Plant Breeding

Pedigree method

• In pedigree method individual plants are selected from F2 and their progenies are tested in subsequent generations. A record of the entire parent off spring relationship is maintained and known as pedigree record. The pedigree may be defined as a description of the ancestor of an individual and it generally goes back to some distant ancestor. So each progeny inevery generation can be traced back to the F2 plant from which it isoriginated.
• This method used for selection from segregating population of crosses in self pollinated crops. It is used for combination or transgressive breeding.

Procedure:

1. Hybridization: The selected parents are crossed to produce a simple / complex cross(F1 seed)

2. F1generation: F1 seeds are space planted to each produces maximum number of F2seed. 15-30 F1plants aresufficient to produce good F2 populations.

3. F2generation: 200-10000 plants are space planted and 100-500 plants are selected and their seeds are harvested separately. He should select as many as F2 plants as he can handle efficiently. The selection depends on skill of the breeder and his ability to judge to select F2 which produce good progeny.

4. F3 Generation: Individual plant progeny are space planted. Individual plant with desirable characters from superior progenies is selected.

5. F4 Generation: Individual plants progenies are space planted desirable pants are selected undesirable progenies are rejected. Progenies are compared visually and more plants are selected from superior progenies. Selection of desirable plants from superior progenies selection is practiced within / between family.

6. F5Generation: Many families have reached homozygous and may be harvested in bulk. The breeder has to assess the yielding potential of progenies, 25-100 progenies are advanced and tested inpreliminary yield trial.

7. F6 Generation: Multi row plots and evaluated visually progenies harvested bulk and they have become homozygous.

8. F7 Generation: Preliminary yield trail with replication to identify the superior progenies. Progenies are evaluated for other component character 2-5 outstanding lines superior to check are advanced to multi location testing.

9. F8 –F10 Generation: Replicated yield trial at several locations. They are tested for yield as well as for resistance.

10. F11: Seed multiplication and release.