Researchers from the University of Illinois have developed a model that treats photosynthesis as a dynamic process rather than an activity that either is or is not happening, allowing the group to examine the impacts of light fluctuations that crop leaves experience due to intermittent clouds, overlying leaves, and the sun's daily passage across the sky.
These light fluctuations are the norm in today's densely planted crops. Lower efficiency of photosynthesis due to slow adjustment to light changes and are estimated to cost up to 40 percent of potential productivity. If crop leaves could be genetically manipulated to adjust more rapidly, then the gain in productivity and efficiency of water use would be substantial.
"When light changes, the plants need time to get used to it. It takes time and decreases efficiency," said Yu Wang, a postdoctoral researcher at Illinois, who led this work for a research project called Realizing Increased Photosynthetic Efficiency (RIPE). In a recent study, RIPE researchers have shown that by treating photosynthesis as a dynamic process, they could improve the response time of C4 plants, (plants that use C4 carbon fixation for photosynthesis) such as corn, to adjust more rapidly to fluctuations in light.
First, the research team validated their model against actual photosynthesis measurements in fluctuating light, which they made in corn, sorghum, and sugarcane. They then used their model to predict which steps in photosynthesis limited the response of the process to fluctuations in light in the three crops. By treating photosynthesis as a dynamic process, the researchers were able to identify the segments of the process that limit the speed of response. Through their modeling and simulation, they identified two proteins they believe are essential in the adjustment.
(Source: Crop Biotech Update, International Service for Acquisition of Agri-Biotech Applications.