A garden pea plant produced axial white flowers . Another of the same species produced terminal violet flowers. Identify the dominant traits.

or

A garden pea plant produced inflated yellow pod and another plant of the same species produced constricted green pods. Identify the dominant traits . How do we find and explain the answer?

To find out the dominant trait among two contrasting traits like white or purple color, one must carry the cross between the parents exhibiting the contrasting traits. The traits which are expressed in progeny i.e. in F1 generation are dominant traits.

For example in the case of cross between plant with axial white flowers and terminal violet flowers the F1 obtained is axial violet showing these traits are dominant over terminal white. This can be explained by the help of following cross.

The ratio obtained in F2 would be 9 axial violet : 3 axial white : 3 terminal violet : 1 terminal white.

You can carry out the cross in similar manner for the pea with inflated yellow pod and another plant of the same species with constricted green pods. In this case F1 will be inflated green pods, showing they are the dominant traits.