XVI International Botanical Congess

As the need for fossil fuel energy increases with increasing population, it is generally accepted that CO2 concentration will reach a mean of 600 ?l/L during the 21st century. For understanding photosynthetic response of rice plants to CO2 enrichment, photosynthetic parameters, activities of antioxidative enzymes and its response to methyl viologen photooxidation in different varieites grown under elevated CO2 concentration were tested. The results indicated that there were both intraspecific and interspecific differences in the response of photosynthesis and yield to elevated CO2. Photosynthetic acclimation was not shown at the end of experiment. Its enrichment might decrease the celluar need for detoxification of active oxygen in cell metabolism, but in strong oxidative stress by MV, a protection to peroxidation damage showed.