A hack to the photosynthesis of tobacco increased its growth by 40 percent, researchers reported today in Science. The team now hopes to make similar changes to soybeans, potatoes, and other food crops.
The researchers from US Department of Agriculture and the University of Illinois at Urbana-Champaign introduced genetic constructs that tweaked a process called photorespiration in tobacco plants. Photorespiration occurs when an enzyme named Rubisco accidentally grabs an oxygen molecule instead of the carbon dioxide that plants need for growth. This snafu, which occurs roughly 20 percent of the time, results in a plant making a toxic chemical called glycolate.
To get rid of the glycolate, plants transform it into useful compounds through a series of chemical reactions that happen in multiple parts of the cell and reduce the photosynthetic efficiency by up to 50 percent. To recover efficiency, researchers gave their tobacco plants genetic instructions that keep the glycolate in one cellular compartment and transform it there.
The researchers tested how these genetically engineered tobacco plants fared under typical farming conditions in a field. The modified tobacco grew around 40 percent more biomass than unaltered plants.
The researchers hope that this tweak to photosynthesis can enhance plants used for food, too. They are currently testing whether these types of modifications help potatoes in greenhouse experiments, reports Science News. And the team plans on running similar experiments with rice, soybeans, and black-eyed peas.
MIT Technology Review notes that it could take decades to both prove that these genetic modifications produce more food and gain regulatory approval for the crops.