Figure 1.

Relationship between the ratio of leaf conductance at 700 μmol mol^-1[CO₂] to that at a 350 μmol mol^-1[CO₂] carbon dioxide concentration and the leaf-to-air-water-vapour pressure difference (VPD). The solid line represents the measurement result of sorghum plants in [Bunce (2001]). The dashed line represents the results of the coupled photosynthesis-stomatal conductance model ([Collatz et al., 1991]). The dot-and-dashed line is based upon the measurement data for rice given in [Morison and Gifford 1983].