In wheat kernel color is determined by additive alleles at t

In wheat, kernel color is determined by additive alleles at two unlinked loci. If two plants, one with dark red kernels (+++– genotype), and one with light red kernels (+– – – genotype), are crossed, what fraction of the offspring is expected to have phenotypes distinct from parental colors?

1/4

4/16

6/16

1/2

10/16

Solution

Here,

Dark red can be considered as RRCCand light red can be considered as rrcc then in F1 generation all will be of intermidiate colour as,

RRCC X rrcc

F1 genearation will be RrCc i.e.intermidiate red,

F2 geneartion will be 1/16 RR CC,

4/16 RR Cc, Rr CC

6/16 RR cc, rr CC, Rr Cc,

4/16 rr Cc, Rr cc

1/16 rr cc

so, 6/16 offspring is expected to have phenotypes distinct from parental colors.