Sport or chimera?

The gardens at the Rashtrapati Bhavan turned out to be more interesting than I had expected. One of the fun things was a bed of pansies around the base of a tree. The gardening staff have been putting out interesting crosses with the Viola tricolor base stock in recent years. Having seen the photos from the past years, I looked carefully at the bed. The featured photo was taken by The Family. You can see two different stalks of the same plant have flowers in two different colours (the one behind is closer to the wild V. tricolor) than the main subject of her photo. How often do you see two differently coloured flowers on the same plant? Not so often that one can ignore it, right?

How can that happen at all? In any organism, different genes can be activated or silenced as the animal grows. The patches of colour on cowhide, or the stripes on a tiger are the most visible example of this. Sometimes a cell mutates during development, and the mutant cell produces more daughter cells with the mutation. This is called a chimera. Some individuals have a patch of coloured skin visible on their body, sometimes called a birthmark. This is due to such a mutation in skin cells. These two things can happen to a plant as well. If the genes for a pigment are switched on or kept off during the development of a flower, then you might have two different colours of flowers on the same plant. These are called sports in botany.

So the pansies that we saw in that one bed in the gardens of the Rashtrapati Bhavan are sports, and chimeras. I wonder if the flowers give rise to seeds which will keep the colour of the flower it came from. If it does, then you can breed multiple cultivars from the same plant. In that case some seeds from this plant could give violet flowers, others white, a third set yellow, and yet another set of seeds could give that tricoloured flower that you see in the featured photo. Is this one of the methods that plant breeders use? Someone with more knowledge than me will have to answer that question.