Biochemistry and Physiology of Carbon Partitioning in Crop Plants

Carbon xation is a biological process that converts atmospheric CO2 (and H2O) into organic carbon compounds (carbohydrates) and O2 due to the photosynthetic capacity of some particular organisms like plants, algae, and cyanobacteria. For the synthesis of carbohydrates, these organisms have a particular set of enzymes acting in cycle to condensate the CO2 with a ve-carbon acceptor, ribulose-1,5-bisphosphate (Rul-1,5-bisP). This process has high energy demands provided as ATP and NADPH, energy-containing compounds that are synthesized by harvesting the solar energy through a specic electron transport chain. The metabolic process generally called “photosynthesis” (more strictly oxygenic photosynthesis) is used to denote the combined capture of light and synthesis of reduced organic molecules, mainly carbohydrates, but both steps occurring by different sets of enzymes (Nelson and Cox 2004). The overall photosynthetic energy balance is represented in Table 9.1 (Equation 9.1).