PI ants with desired traits are tested for homozygosity and two such plants are crossed and seeds obtained to raise the F population. Large number of F, individuals is raised and self pollination is allowed among plants with dominant traits.
Selection again is carried out among the F2 population. Good ones are again selected and sown. In this way progenies up to F4 or Fs are raised, when individuals become almost homozygous for the desired trait. The seeds are now ready for use.
Pedigree method is suitable for plants, where traits can be easily observed as in case of tobacco, cotton, soya beans etc.
(d) Bulk method:
Several plants are selected as the parents and cross pollination is carried out among them. The F, progeny is allowed to self pollinate and large number of F2 individuals are raised. (In pedigree method cross pollination is carried between two selected individuals).
The F2 seeds are sown in bulk (not separately). Natural selection is allowed to operate in all these crosses and the desired ones are selected at the end of the F6 or F8 generations. Bulk method is suitable for small grained crops.