In garden pea, violet flower colour (V) is dominant over white flower colour (v). A researcher wishes to determine the exact genotype of a plant bearing violet flowers. Which of the following crosses should the researcher perform?

Step-by-step solution

To determine the exact genotype of a plant showing a dominant phenotype (violet flowers, which could be VV or Vv ), a test cross is performed. In a test cross, the individual with the unknown genotype is crossed with a homozygous recessive individual. Here, the homozygous recessive plant has white flowers ( vv ). If the unknown plant is homozygous dominant ( VV ), all offspring will have violet flowers ( Vv ). If the unknown plant is heterozygous ( Vv ), the offspring will show a 1:1 ratio of violet ( Vv ) to white