A Perplexing Result

If you guessed the top flower with the deeper purple, you’re in good company. That’s what the scientists doing the experiment expected.

But the actual result looked like the lower flower—variegated petals with sections of no pigment.

How could adding copies of a gene for enhancing pigment result in less pigment?

A dark purple petunia with an X over it and one with alternating petals of purple and white.