A garden center is generating new strains of petunias for sale. A blue-flowered strain, when self-crossed, produced plants where 24 had deep purple, 51 had blue, and 25 had white flowers. An orange-flowered strain, when self-crossed, produced plants where 21 had orange flowers, 15 had dark orange, 16 had light orange, 6 had orange-red, 6 had golden, 1 had red, and 2 had yellow flowers. They realized that:

1. the blue-flowered strain was heterozygous for a single incompletely dominant trait locus
2. the blue-flowered F1 plants would be pure-breeding when self-crossed
3. the orange-flowered strain showed evidence of polygenic alleles
4. self-crossing the yellow-flowered plants would be likely to produce a high proportion of plants with yellow flowers
5. some, but not all, of the flower colors in petunias are controlled by quantitative trait loci

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