Explain the law of independent assortment with reference to seed shape and seed colour in garden tea plant.

Explanation

Law of independent assortment states that when two pairs of traits are combined in a hybrid, segregation of one pair of character is independent of the other pair of character. In a dihybrid cross, R represents a gene for round shape, r- gene for wrinkled and Y represents the gene for yellow colour and y-gene for green colour. The genotype producing round, yellow seed RRYY and a wrinkled green seed is rryy. The parents were homozygous for both pairs of factors.
The RRYY parent produce gametes carrying RY factor and rryy parent produce gametes carrying ry factor. When RY and ry gametes come together during `F_(1)` generation, offspring will be RrYy and would produce a round and yellow seed, since R is dominant over r and Y is dominant over y. The `F_(2)` generation of dihybrid cross yielded four types of gametes - RY, Ry, rY. ry.
Phenotypic ratio - `9:3:3:1`