Scientists look to increase crop production by speeding up photosynthesis

How does one improve the amount of food a crop yields? Speed up the way that plant eats.

A new study published last week in the journal Nature details a group of scientists that were able to genetically engineer a tobacco plant with a faster enzymes from blue-green algae, or cyanobacteria, to allow it conduct photosynthesis more quickly. With sped-up photosynthesis — the process that allows plants to convert sunlight, carbon dioxide and water into oxygen and the sugar sucrose — scientists hope that food yields from crops such as wheat and rice can be multiplied up to 60 percent.

The secret is keeping the enzyme Rubisco away from oxygen and exposing it to more concentrated pockets of carbon dioxide:

In many crop plants, including tobacco, Rubisco is less reactive with oxygen, but a trade-off leads to slower carbon fixing and photosynthesis, and thus, smaller yields. The Rubisco in cyanobacteria fixes carbon faster, but it is more reactive with oxygen. As a result, in cyanobacteria, Rubisco is protected in special micro-compartments (called carboxysomes) that keep oxygen out and concentrate carbon dioxide for efficient photosynthesis.

“This is the first time that a plant has been created through genetic engineering to fix all of its carbon by a cyanobacterial enzyme,” said Maureen Hanson, plant geneticist and a co-author of the study from Cornell University.

The hope is more efficient yields from the same crops would be a possible solution to the finite amount of farmable land.