As the planet continues to warm, plants face a dilemma. Stomata, the same
tiny opening in their leaves they have to open to exchange gases also
release water. They can close the holes to stay hydrated in hotter, drier
conditions, but may miss out on critical carbon dioxide in doing so.
A research team at the Bergmann Lab at Stanford University figured out how
plants regulate the number of stomata that each leaf develops. Using
Arabidopsis, the team looked at cytokinin, an important plant hormone that
was long thought to influence stomatal development and coordinate it with
other processes happening throughout the plant.
Anne VatÚn, lead author of the paper published in Developmental Cell,
analyzed the entire genome of Arabidopsis thaliana and confirmed that genes
associated with cytokinin were indeed highly active in cells that were about
to become stomata. The research team found that by dialing up or down the
levels of this hormone in specific cells in hundreds of laboratory plants,
the researchers found they could subtly alter the number of stomata the
plant makes. They also discovered that cytokinin activates the gene
SPEECHLESS that puts cells on the path toward becoming stomata.