The following progeny are obtained from a test cross of a trihybrid wild-type plant to a plant with the recessive phenotypes compound leaves (c), intercalary leaflets (i), and green fruits (g). (Traits not listed are wild type.) The test-cross progeny are as follows:
Phenotype Number
Compound leaves 324
Compound leaves, intercalary leaflets 32
Compound leaves, green fruits 5
Compound leaves, intercalary leaflets, green fruits 51
Intercalary leaflets 3
Intercalary leaflets, green fruits 309
Green fruits 42
Wild type 49
815
Determine the order of the three genes, and construct a genetic map that identifies the correct order and the alleles carried on each chromosome in the trihybrid parental plant.
4. Genetic Mapping and Linkage
Trihybrid Cross