Question

In an experiment on pure pea plants, plants with round yellow seeds were crossed with plants producing wrinkled green seeds. What will be the phenotypic ratio of the progeny of f1 generation?

Answer 1

During Mendel's experiment with dihybrid cross, it was seen that all the plants in F1 generation produced round and yellow seeds.

Answer 2

The phenotypic ratio of plants in F2 generation is -

9:3:3:1 ( Round yellow: Round green: Wrinkled yellow: Wrinkled green).

The genotypic ratio of the plants in F2 generation is-

1:2:1:2:4:2:1:2:1 ( RRYY: RRYy: RRyy: RrYY: RrYy: Rryy: rrYY: rrYy: rryy).

Round yellow is a dominant trait over wrinkled green. When the given parental plants (with genotype RRYY and rryy) are crossed, they will produce RrYy (Round yellow offsprings) in the F1 generation. Now parents with genotype RrYy will interbreed and produce phenotypes in the ratio 9:3:3:1 and genotypes in the ratio 1:2:1:2:4:2:1:2:1 in the F2 generation.