Question

In radishes, two incompletely dominant genes control color and shape. Red and white radishes are homozygous, whereas the hybrid is purple. Long and round radishes are homozygous and if crossed will produce an oval hybrid. Complete a punnett square to show the genotypes and phenotypes produced by crossing pure breeding red long radishes with white round radishes.

Answer 1

The correct answer would be:

• Phenotypic ratio: All are Purple and oval.
• Genotypic ratio: RrLl

Let us consider R and L be the genes for color and shape of the radish respectively.

As both are incomplete dominant genes, the genotypes and phenotypes would be

• RR - Red color
• rr - White color
• Rr - Purple color
• LL- Long shape
• ll - Round shape
• Ll - Oval shape

So, the genotype of pure breed red and long radish would be RRLL.

Similarly, the genotype of the pure breed white and round radish would be rrll.

The cross would result in the production of offspring with genotype RrLl.

Thus, the phenotype of all the offspring would be purple and oval radish.