ABSTRACT
Environmental stresses alter the growth and productivity of crop plants by affecting the key metabolic pathways. Among these pathways, photosynthesis 14holds a key position contributing immensely to overall development and productivity. The tolerance levels to different abiotic stresses vary considerably from species to species. Abiotic stresses significantly alter photosynthetic functioning by upsurging the production of toxic reactive oxygen production leading to disruption of the photosynthetic components like electron transport, photosystems I and II, adenosine triphosphate (ATP) generation, and carbon fixation by overall influence on the enzymes regulating the carbon fixation process. Both C3 and C4 systems display differential behavior in response to abiotic stresses. The alteration in the stomatal and nonstomatal attributes ultimately affects the photosynthesis considerably. Designing plants with improved photosynthetic functioning is imperative with focus on the antioxidant machinery of the chloroplast, PSII repair mechanisms, redox homeostasis, and the associated signaling components. The present review addresses the influence of abiotic stresses on photosynthetic functioning and the mechanisms contributing to amelioration of the damaging effects.
