Plant photosynthesis under abiotic stresses: Damages, adaptive, and signaling mechanisms

Photosynthesis is crucial for sustaining life on this planet and necessary for plant growth and development. Abiotic stresses such as high and low temperatures, and excess, or deficit of water limit the crucial plant processes, thus threatening the global food security. However, recent molecular approaches allowed elucidation of the photosynthetic components/compounds and their efficiency under stress conditions. In the present scenario, these approaches are not enough to reduce the yield penalty due to the reduction in photosynthetic efficiency. Therefore, comprehensive data on plant behaviour and stress crosstalk networks could assist in understanding the in-depth mechanism of photosynthesis. In recent years, information regarding crosstalk, signalling characterization of candidate genes, and responses to multiple stressors have advanced our knowledge to understand the mechanism of photosynthesis. Therefore, in this review, we provide a comprehensive overview of various studies conducted on photosynthesis under multiple abiotic stress factors that affect the photosynthetic efficiency of a plant. We also discuss the role of crosstalk signalling compounds (plant growth regulators and micro RNAs) for an in-depth understanding of the photosynthesis mechanism. Finally, based on our gathered data set, the mechanism of damage and adaptive response of photosynthesis under multiple stressors are explained to enhance the scientific community's knowledge toward boosting photosynthesis and to accelerate stress tolerance strategies for crop improvement.