When combined back into an octoploid new dahlia that combines ALL this information However, BbbaaaaYYyyIIIi is how it is described, or shorter yet B1Y2I3, ignoring the fully recessive a's. This looks tetraploid, but it is a shorthand form which only shows the effective genes. For simplicity, we assume that the factors are all on separate chromosomes and that they are independently inherited, but that is not correct and many are linked in any given cultivar. Mutation events CAN separate them and this has happened in every case. I's are possible but less likely.
Whites are the key to tracking, if that is desired since they are blank for all colors.
Thus breeding with them will give clear indications of the make up of the colored mate. This is a lot of work and it is complicated by the incompatibility between many dahlias. Lawrence did that work for the following table. The sticky fluid on the stigma contains nutrient to support the process of pollen germination leading to fertilization. This means that a lot of crosses simply don't work, and no data can be obtained.