In radishes, red and white are pure-breeding colors, while hybrids are purple. If a red (RR) radish is crossed with a white (WW) radish, what will be the phenotype of the F_2 generation (assuming the F_1 generation self-pollinates)? Solution Cross between RR and WW would produce RW as F1. Now assuming that RW is self crossed, we get F2 as following: 1 RR (RED) 2 RW ( PURPLE) 1 WW (WHITE) Hence, the ratio is 1:2:1. It is a case of INCOMPLETE DOMINANCE..