Explain with an example the inheritance of dihybrid cross.How is it different from monohybrid cross?

Explanation

The dihybrid cross involves the inheritance of two pairs of contrast characteristics, round - yellow seeds and wrinkled - green seeds.
When pea plants having round- yellow seeds cross bred with pea plant having wrinkled - green seeds, in the first generation `(F_1)` only round yellow seeds were produced
No wrinkled - green seeds were obtained. Round yellow colour seeds were dominant and wrinkled-green seeds were recessive. When round-yellow seeds were cross bred by self-pollination, four types of seeds having different combinations of shape and colour were obtained in `F_2` generation. They were round yellow , round green , wrinkled yellow , wrinkled green
The phenotypic ratio in `F_2` generation is 9:3:3:1
i.e. 9-Yellow, round
3-Yellow , wrinkled
3-Green , round
1-Green, wrinkled