Incomplete dominance is the ability of two alleles to produce a heterozygous phenotype different from the two homozygous phenotypes.
Example is when a pure stock of red flowered (RR) four o'clock plant is been crossed with a white flowered(rr) one, the offspring are all pink flowered(Rr), showing a blending of flower colour character. Self pollination of the pink flowered F1 individual produce a mixture of F2 individual bearing red, pink and white flowers in the ratio of 1:2:1. This reappearance of the red flowered and white flowered forms in the F2 generation shows that alleles R and r have remained unaltered in the F1 generation.
