Plants generate their energy from sunlight via photosynthesis, however many crops have a photosynthetic glitch, which costs them a significant amount of energy that could be used for growth. This glitch has been shortened using careful engineering by researchers from the University of Illinois and US Department of Agriculture’s Agricultural Research Service, to generate plants with a 40% increase in productivity in real-world conditions.

 

Tobacco seedlings. Image: Claire Benjamin/RIPE project

During photosynthesis, carbon dioxide (CO2) and water are converted into sugars by the enzyme Rubisco, which is fuelled by energy from sunlight. Rubisco is the planets most abundant protein, but its efficiency has resulted in an oxygen-rich atmosphere, and it cannot reliably distinguish between CO2 and oxygen (O2). Approximately 20% of the time, O2 is grabbed by Rubisco instead of CO2, and then converted into a compound which is toxic to plants. This compound can be recycled through a process known as photorespiration.

 

The research team.  Image: Claire Benjamin/RIPE project

In this study, alternate routes for the process have been engineered, allowing the plant to save resources better utilised for growth. The scientists generated three alternate routes using different sets of promoters and genes, which were then stress tested in 1,700 individual plants to find the best performers.