“Very reminiscent of what occurs in the Romanesco,” Dr. Godin said proudly.
Normally, when a plant sprouts a flower, the flowering tip of the plant prevents more growth from the stem. A cauliflower curd is a bud that was designed to become a flower but never makes it all the way there, and instead makes a shoot. But the researchers’ experiments in the meristem found that because this shoot has passed through a transient floral stage, it is exposed to a gene that triggers its growth. “Because you have been a flower, you are free to grow and you can make a shoot,” Dr. Parcy said.
This process creates a chain reaction where the meristem is creating many shoots that, in turn, creates many more shoots, enacting the fractal geometry of a cauliflower.
“It’s not a normal stem,” Dr. Godin said. “It’s a stem without a leaf. A stem with no inhibition.”
“That’s the only way to make a cauliflower,” Dr. Parcy said.
The researchers say there are likely other mutations responsible for the spectacular shape of Romanesco. Ning Guo, a researcher at the Beijing Vegetable Research Center who is also studying the potential genetic mechanism behind the architecture of the cauliflower curd, says the paper has offered “a lot of inspiration.”
“The story is not yet finished,” Dr. Godin said, adding that he and Dr. Parcy will continue refining their cauliflower models. “But we know we are on the right track.”
But they are open, they say, to studying anything that flowers.