The phenotypic ratio of the offspring will be 1 red: 1 yellow if a true-breeding yellow pepper plant is crossed with a dihybrid pepper plant.
Phenotypic ratio is the ratio of the phenotype of offspring produced from a cross between two parents.
Let the allele for yellow be y and red Y.
Let the allele for early chlorophyll break down be E and late loss be e.
The genotype of the parents are as follows:
The cross is as follows: yyEE × YyEe
The offspring produced will be:
yyEE, yyEe, YyEe, YyEe
The offspring will be: 2 yellow, 2red peppers
Therefore, the phenotypic ratio is 1 red: 1 yellow.
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