“Answering this question is a huge step toward understanding how we can make the most robust and productive crops possible.”
To harness the power of the sun and make sugars for energy storage, plants use photosynthesis. But some plants are more efficient at it than others. For the first time, researchers have identified a key step in the transformation between old-fashioned C3 photosynthesis and new and improved C4 photosynthesis — which could lead to the development of more efficient, more resilient “super crops,” SciTechDaily reports.
Scientists at the Salk Institute in San Diego, California, collaborated with researchers at the University of Cambridge to make the breakthrough, charting the evolution of plants over millions of years.
While 95% of plants use C3 photosynthesis, SciTechDaily explained, a new group of plants evolved to use C4 photosynthesis around 30 million years ago.
C3 gets the job done, but it has flaws. It fails and uses the wrong molecule about 20% of the time, whereas C4 eliminates this inefficiency and the need to break down the incorrect molecule afterward. Plus, C3 requires the plant’s pores to stay open longer waiting for carbon dioxide, which means the plant loses water; whereas C4 plants retain their water and are much more resilient to heat and drought.
Extremely efficient sugar production plus heat and drought tolerance is a winning combo in a crop. C4 photosynthesis is what makes corn such a great staple, for example.
If that property could be transferred to C3 crops, they’d be much more resilient and useful in an overheating world.
“Asking what makes C3 and C4 plants different is not just important from the basic biological perspective of wanting to know why something evolved and how it functions on the molecular level,” said Professor Joseph Ecker, senior author of the study, per SciTechDaily. “Answering this question is a huge step toward understanding how we can make the most robust and productive crops possible in the face of climate change and a growing global population.”
It turns out that the big difference between the two groups of plants doesn’t come from adding or subtracting genes, but from how the genes are regulated — basically, how they turn on and off in different cells.
“Now we’ve got this blueprint for how different plants utilize the sun’s energy to survive in different environments,” said Joseph Swift, co-first author of the study, per SciTechDaily. “The ultimate goal is to try to switch C4 photosynthesis on and, in turn, create more productive and resilient crops for the future.”
The team’s continuing research is aimed at turning on C4 photosynthesis in rice — a project shared with a global network of collaborators whose work could generate an incredible new, reliable food crop.
