Two genes of a flower, one controlling blue (B) versus white (b) petals and the other controlling round (R) versus oval (r) stamens, are linked and are 10 map units apart. You cross a homozygous blue oval plant with a homozygous white round plant. The resulting F1 progeny are crossed with homozygous white oval plants, and 1,000 offspring plants are obtained. How many plants of each of the four phenotypes do you expect?

The genotype of the homozygous blue oval plant isBBrr, and the genotype of the homozygous white round plant isbbRR. The gametes produced from theBBrrplant areBr, and the gametes produced from thebbRRplant are bR.

Thus, when both the plants are crossed (BBrr × bbRR), the genotype of the F1 progeny is BbRr.

The genotype of homozygous white oval plants isbbrr.

Four different progenies are produced when F1 progeny (BbRr) is crossed with the homozygous white oval plant (bbrr). The phenotypes and genotypes of the offspring are blue round (BbRr), blue oval (Brrr), white round (bbRr), and white oval (bbrr).

Some of the offspring obtained are of parental types, and some are recombinants. The blue oval and white round plants are of a parental type, and the blue round and white oval are recombinants.

The genes that control the color and shape of stamens are ten map units apart. This meansthe recombination frequency between the genes is 10%.The number of offspring produced is 1000.

The number of recombinants can be calculated using the formula for recombinant frequency. The formula:

$Recombinationfrequency=\frac{Numberofrecombinants}{Totalnumberofoffsprings}\times 100$

The number of recombinants is calculated as:

$10=\frac{Numberofrecombinants}{100}\times 100$

Thus, the number of recombinants is 100.

The number of recombinants is 100, which means 50 each of blue round and white oval plants is produced as these are recombinants.The remaining 900 (1000-100) offspring are of the parental type.This means 450 each of blue oval and white round plants are obtained.

Thus, 50 each type of recombinants and 450 each of parental type plants are produced.