Stomatal response to VPD in C plants with different biochemical sub-pathways.

C NAD-malic enzyme (NAD-ME) species occurs in drier regions and exhibit different drought responses compared to C NADP-malic enzyme (NADP-ME) species. However, a physiological mechanism explaining the geographical discrepancies remains uncertain. This study examined gas exchange patterns that might explain different distributions observed between two subtypes of C photosynthesis.