Title: Photosynthetic targets for improving crop tolerance to ozone Authors
Submitted to: International Congress of Photosynthesis
Publication Type: Abstract Only
Publication Acceptance Date: May 29, 2013
Publication Date: N/A
Technical Abstract: Ozone (O3) is an air-born pollutant that has increased in the atmosphere from industrial activities. Current O3 concentrations exceed the threshold for damage to plants, and globally, $14-$26 billion in potential crop productivity is estimated to be lost to O3 stress each year. Sensitivity of C3 crops to O3 is well-established; however, developing O3 tolerance in major crops has not been an industrial priority to date. Photosynthesis is particularly sensitive to O3, and recent proteomics studies have demonstrated that many components of the photosynthetic apparatus, including light-harvesting complexes, ATP synthase and Calvin cycle enzymes are negatively impacted by O3. Increasing O3 concentration by 25% above current ambient levels reduces photosynthesis in major C3 food crops by 10% and reduces stomatal conductance by 15%. Much of the reduction in photosynthesis occurs late in leaf development as O3 accelerates the process of senescence, which coincides with the critical period in reproductive development that determines yield. Here, we discuss recent experiments detailing the effects of chronic elevated O3 on leaf primary metabolism and photosynthesis, and identify potential targets for improving crop tolerance to O3.