The Law of Independent Assortment states that during a dihybrid cross (crossing of two pairs of traits), an assortment of each pair of traits is independent of the other. In other words, during gamete formation, one pair of trait segregates from another pair of traits independently. This gives each pair of characters a chance of expression.In the dihybrid cross, he chose round-yellow seed and wrinkled green seed and crossed them. He obtained only round yellow seeds in the F1\xa0generation. Later, self-pollination of F1\xa0progeny gave four different combinations of seeds in the F2\xa0generation. He obtained round-yellow, wrinkled-yellow, round green and wrinkled green seeds in the phenotypic ratio 9:3:3:1.The phenotypic ratio 3:1 of yellow: green colour and the ratio 3:1 of the round: wrinkled seed shape during monohybrid cross was retained in the dihybrid cross as well. Thus, he concluded that characters are distributed independently and inherited independently. Based on this observation, he developed his third law – Law of Independent Assortment.