This new volume aims to be the single source that discusses in a comprehensive and elaborate way the photosynthetic and respiratory mechanisms in plants under hostile situations and the proper mitigating strategies to continue uninterrupted photosynthesis and respiration under such situations. Photosynthesis and respiration are the two main physiological processes for sugar biosynthesis and mobilization for driving all other vital functions. This volume delivers a wealth of sound information on these processes for scientists, researchers, and academicians.With chapters from renowned scientists, researchers, and global leaders, this volume focuses on the effect of environmental stressors on photosynthetic pigments, photosystems, activities of photosynthetic enzymes and protein complexes, PSII photochemistry, carbon fixation pathways, photosynthetic efficiency, glycolytic and Krebs cycle pathways, and ATP production and electron transport chain of plants. The recovery of photosynthesis and respiration through application of phytohormones, signaling molecules, and other protective agents are also emphasized. Genetic engineering to enhance photosynthetic efficiency is highlighted as well.