Leaf O2 uptake in the dark is independent of coincident CO2 partial pressure

Elevated CO2, in the dark, is sometimes reported to inhibit leaf respiration, with respiration usually measured as CO2 efflux. Oxygen uptake may be a better gauge of respiration because non-respiratory processes can affect dark CO2 efflux in elevated CO2. Two methods of quantifying O-2 uptake indicated that leaf respiration was unaffected by coincident CO2 level in the dark.