Mechanisms Regulating the Dynamics of Photosynthesis Under Abiotic Stresses

Abstract

Photosynthesis sustains plant life on earth and is indispensable for plant growth and development. Factors such as unfavorable environmental conditions, stress regulatory networks, and plant biochemical processes limits the photosynthetic efficiency of plants and thereby threaten food security worldwide. Although numerous physiological approaches have been used to assess the performance of key photosynthetic components and their stress responses, though, these approaches are not extensive enough and do not favor strategic improvement of photosynthesis under abiotic stresses. The decline in photosynthetic capacity of plants due to these stresses is directly associated with reduction in yield. Therefore, a detailed information of the plant responses and better understanding of the photosynthetic machinery could help in developing new crop plants with higher yield even under stressed environments. Interestingly, cracking of signaling and metabolic pathways, identification of some key regulatory elements, characterization of potential genes, and phytohormone responses to abiotic factors have advanced our knowledge related to photosynthesis. However, our understanding of dynamic modulation of photosynthesis under dramatically fluctuating natural environments remains limited. Here, we provide a detailed overview of the research conducted on photosynthesis to date, and highlight the abiotic stress factors (heat, salinity, drought, high light, and heavy metal) that limit the performance of the photosynthetic machinery. Further, we reviewed the role of transcription factor genes and various enzymes involved in the process of photosynthesis under abiotic stresses. Finally, we discussed the recent progress in the field of biodegradable compounds, such as chitosan and humic acid, and the effect of melatonin (bio-stimulant) on photosynthetic activity. Based on our gathered researched data set, the logical concept of photosynthetic regulation under abiotic stresses along with improvement strategies will expand and surely accelerate the development of stress tolerance mechanisms, wider adaptability, higher survival rate, and yield potential of plant species.

Exogenous Gibberellic Acid or Dilute Bee Honey Boosts Drought Stress Tolerance in Vicia faba by Rebalancing Osmoprotectants, Antioxidants, Nutrients, and Phytohormones

“…In the current study, leaf photosynthetic pigment contents (total chlorophylls and carotenoids), photochemical activity, SPAD chlorophyll index, and photosynthetic efficiency (F v /F m and PI) were reduced while the irrigation water was reduced to 60% ETc, indicating chlorophyll degradation in chloroplasts and photoinhibition of PSII of waterstressed faba bean plants due to the damaging influences of ROS [54,55]. However, leaf photosynthetic pigment contents, photochemical activity, SPAD chlorophyll index, and photosynthetic efficiency (Table 2) were markedly improved by foliar-applied Db-H [38] or GA 3 [22].…”

Foliar Spray of Alpha-Tocopherol Modulates Antioxidant Potential of Okra Fruit under Salt Stress

“…It influences plant performance, limiting its production and causing water shortages to the plants. Salinity also negatively affects chlorophyll, the photosynthetic apparatus, and chloroplast ultra-structure, and may cause cell death [ 21 , 22 ]. Salinity-induced ROS triggers phytotoxic reactions and adversely affects the cellular processes of plants, causing tissue damage due to the oxidization of macro-molecules such as proteins and lipids.…”

Modulation of Photorespiratory Enzymes by Oxidative and Photo-Oxidative Stress Induced by Menadione in Leaves of Pea (Pisum sativum)

“…We used high light and oxidative stress (by MD), as such combination occurs in nature [ 44 , 45 , 46 ]. The amplified effects of oxidative stress (due to drought or other conditions) under high light conditions are reflected in the responses of photosynthesis and photoinhibition [ 47 , 48 ]. Our work demonstrated the importance of mitochondrial metabolism in protecting photosynthesis against photoinhibition.…”