Coupling Between CAM and Movements of Stomata

Similar to the CO2 exchange pattern (see Chap. 5.1.2), any given plant may show variations in the basic pattern of stomatal behavior mainly in response to environmental factors (see Chap. 5.3.4). 

Crassulacean succulents, e.g., Kalanchoe daigremontiana, have much the same pattern, but frequently show stomatal opening in the afternoon (Fig. 5.21). The afternoon opening could be the result of a reduced partial pressure of CO2 after organic acid depletion and photosynthetic reduction of endogenously produced CO2 as outlined in Chapter S.3.2.2. 

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