A common weed holds important clues on how to breed drought-tolerant crops in a world beset by climate change.
Yale scientists describe remark Portulaca oleracea, commonly known as purslane. they report August 5 in the journal Science Improvements.
“This is a very uncommon combination of attributes and has created a kind of ‘super plant’ – a which could potentially be useful in endeavors such as crop engineering,” said Erika Edwards of Yale, professor of ecology and evolutionary biology and lead author of the paper.
the process by which green plants use sunlight to synthesize nutrients from carbon dioxide and water. For instance. which allows the plant to remain successful at high temperatures. which helps them survive in deserts and other areas with little water.
What makes purslane unique is that it has these two adaptations scalable, allowing it to be both highly productive and highly drought tolerant, an unlikely combination for a plant. Most scientists thought that C4 and CAM worked independently in purslane leaves.
But the Yale team, led by co-corresponding authors and postdoctoral researchers Jose Moreno -Villena and Haoran Zhou, conducted a spatial analysis of gene expression in purslane leaves and found that C4 and CAM activity are fully integrated. They operate in the same cells, with the products of CAM reactions being processed through the C4 pathway. This system offers unusual levels of defense for a C4 plant in times of drought.
Researchers also constructed metabolic flux models that predicted the emergence of a system integrated C4+CAM that reflects their experimental results.
Understanding this new metabolic pathway could help scientists to devise new ways to engineer crops such as maize to help withstand prolonged drought, according to the authors.
“In terms of engineering a cycle CAM in a C4 crop, like corn, there’s still a lot of work to do before it becomes a reality,” Edwards said. “But what we’ve shown is that both paths can be effectively integrated and share products. C4 and CAM are more compatible than we thought, leading us to suspect that there are many more C4+CAM species out there, waiting to be discovered.”