Carbon Dioxide Efflux from Leaves in Light and Darkness

Abstract
Efflux of carbon dioxide in light and darkness was measured at low ambient CO2 concentrations in leaves of Rumex acetosa. Light carbon dioxide production (photo‐respiration) was found to depend on irradiance and to differ from dark production as to the response to temperature and ambient concentrations of O2 and CO2. These observations support previously made suggestions that photorespiration follows a different metabolic pathway to dark respiration.