Answer:
RrYy x RrYy
Explanation:
Given
Round (R) allele is dominant over wrinkled allele "r"
and Yellow seed allele (Y) is dominant over green seed allele "y"
If I find a plant with round and yellow seeds and want to determine its genotype, then I will cross it with plant that has heterozygous genotype for both the characteristics i.e "RrYy"
Let us say that the plant I found is heterozygous dominant for both the traits i.e "RrYy"
If RrYy is crossed with another RrYy ,we get -
RY Ry rY ry
RY RRYY RRYy RrYY RrYy
Ry RRYy RRyy RrYy Rryy
rY RrYY RrYy rrYY rrYy
ry RrYy Rryy rrYy rryy
Thus, the possible gnotypes would be
RRYY-1
RRYy-2
RrYY-2
RrYy-4
RRyy- 1
Rryy-2
rrYY-1
rrYy-2
rryy-1
The phenotypic ration for this cross is[tex]9:3:3:1[/tex]. This is a standard cross result between two heterozygous parents.