Fruit color in a particular plant is controlled by a set of three quantitative traits that work in an equal and additive manner. Each trait has two alleles (i. e., A and a); each allele represented by a capital letter produces one dose of yellow pigment, while alleles represented with lower case letters do not produce any pigment at all. How many different shades of yellow fruit color are there

7

Explanation:

The number of distinct shades of fruit color would be 7. It is given that the color is dominated by a group of three QTL(quantitative traits) with each trait having two alleles(A,a). Out of these two alleles, one represented by a capital letter(A) generates a single dose of yellow pigment while the latter represented by a smaller case letter(a) does not generate any pigment. Since there is no environmental effect, the number of various yellow shades would be 7 through the combinations of yellow and colorless pigments(A/a, A/a, A/a, A).