Photosynthesis and respiration in Elodea canadensis Michx

• Main Author: Simpson, Philip Stanley
• Published: University of Liverpool 1981
• Subjects: 572
• Online Access: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.637473

Oxygen effects on photosynthesis end respiration in detached leaves of Elodea canadensis were determined over a range of conditions which the plant experiences in shallow water. Its photosynthesis was inhibited by 02 under all light, temperature, CO2 and pH conditions but this was not caused solely by accelerated dark respiration. These effects were comparable to those described in terrestrial C3 plants. The enhancement of O2 inhibition of photosynthesis by high 02' pH and low CO2 suggests that similar field conditions could lead to major losses in photosynthesis and might explain some of the biomass losses under still water conditions. Compared to the filamentous algae Cladophora glomerata and Spirogvra sp., its photosynthesis was impaired, especially at high pH and low CO2.