The test cross is a cross, which is performed to determine the genotype of a given organism. in this case, the individual is crossed with homozygous recessive organism
In case the plant is showing a dominant phenotype, then it can either be homozygous or heterozygous dominant. On crossing with homozygous recessive individual, the homozygous dominant individual produces all dominant offspring, whereas, the heterozygous dominant produces 50% dominant offspring and 50% recessive offspring. Hence, by observing the result of the test cross, one can determine the genotype of the plant.
