Let the gene for tall habit of pea plant be represented by ‘T’ and dwarf habit be represented by ‘t’.
Let the gene for round-seed be represented by ‘R’ and that of wrinkled seed be represented by gene ‘r’.
Then, the genotypes of the parents would be:
i. Homozygous tall, round-seeded – TTRR
ii. Homozygous dwarf, wrinkled seeded – ttrr
The above example of a dihybrid cross between homozygous tall, round-seeded pea plant and dwarf, wrinkled-seeded pea plant explains the ‘Law of Independent Assortment’.
The law of independent assortment states that “when two parents differing from each other in two or more pairs of contrasting characters are crossed, then the inheritance of one pair of character is independent of the other pair of character.”