Figure 9
Carbon balance in plants exposed to 1 (1D plants) or 3 (3D plants) drought cycles. Blue arrows indicate anabolic process (photosynthesis) and red arrows indicate catabolic processes. The thickness of the arrow indicates the intensity of the process. Plants that experienced 3 drought cycles were able to keep their stomata open and, consequently, had a higher rate of carbon fixation, which was directed to defense mechanisms. Activation of defense responses maintained cell integrity, which allowed maintenance respiration to continue at levels similar to control. In plants exposed to a single drought cycle, stomatal closure resulted in less carbohydrate production, which associated with less activation of defense mechanisms triggered several cellular damages. The high increase in maintenance respiration in these plants required the deviation of metabolites from other pathways to the TCA cycle.
