Two genes $\mathrm{R}$ and $\mathrm{Y}$ are located very close on the chromosomal linkage map of maize plant…
Two genes $\mathrm{R}$ and $\mathrm{Y}$ are located very close on the chromosomal linkage map of maize plant. When RRYY and rryy genotypes ore hybridized, the $\mathrm{F}_2$ segregation will show:
segregation in the expected $9: 3: 3$ : 1 ratio
segregation in 3:1 ratio
higher number of the parental types
higher number of the recombinant types.
Solution
When the linked genes are situated quiteclose, the chances of crossing over arehighly reduced. Due to this, large number of parental gametes are formed and only few recombinant gametes are formed. This results in higher number of parental typesin $\mathrm{F}_2$ generation as compared to recombinants.