Figure 1.

Patterns of carbon assimilation (A), stomatal conductance (g_s), and intrinsic water use efficiency (W_i) under continuous light conditions for different species. Each point represents the mean of at least three replicates that were measured in the second subjective day under continuous illumination in Arabidopsis (Dodd et al., 2005), Gossypium hirsutum (Resco de Dios et al., 2016), L. esculentum (Corlett et al., 1998), M. indica (Allen et al., 2000), and P. vulgaris (Resco de Dios et al., 2016). Data originates from different studies, but the entrainment phase always consisted of 12 h of day and of night (except Allen et al. [2000], where daylength was 11 h). There were differences in radiation and temperature across studies leading to differences in flux rates across species. Consequently, plotted values represent normalized values of A, g_s, and W_i. Normalization was done by dividing each value by the maximum value for that species.