A C-assay for photorespiration in aquatic plants.

The (14)C-assay developed by Zelitch to evaluate photorespiration was modified for use in submersed aquatic plants in the laboratory and in situ. Results in laboratory cultures of Najas flexilis suggest that photorespiration occurs but is limited in comparison to terrestrial C(3) plants and is related to the rate of diffusion of CO(2) from the plant and to the carrying capacity of water for dissolved oxygen.