Phytohormones Regulate Accumulation of Osmolytes Under Abiotic Stress

Abstract

Plants face a variety of abiotic stresses, which generate reactive oxygen species (ROS), and ultimately obstruct normal growth and development of plants. To prevent cellular damage caused by oxidative stress, plants accumulate certain compatible solutes known as osmolytes to safeguard the cellular machinery. The most common osmolytes that play crucial role in osmoregulation are proline, glycine-betaine, polyamines, and sugars. These compounds stabilize the osmotic differences between surroundings of cell and the cytosol. Besides, they also protect the plant cells from oxidative stress by inhibiting the production of harmful ROS like hydroxyl ions, superoxide ions, hydrogen peroxide, and other free radicals. The accumulation of osmolytes is further modulated by phytohormones like abscisic acid, brassinosteroids, cytokinins, ethylene, jasmonates, and salicylic acid. It is thus important to understand the mechanisms regulating the phytohormone-mediated accumulation of osmolytes in plants during abiotic stresses. In this review, we have discussed the underlying mechanisms of phytohormone-regulated osmolyte accumulation along with their various functions in plants under stress conditions.

Gene expression profile indicates involvement of uniconazole in Coix lachryma‐jobi L. seedlings at low temperature

“…Low temperatures could decrease level of Ros in study, in which results were inconsistent with Sharma(Sharma, Shahzad, Kumar, et al, 2019;Sharma, Shahzad, Rehman, et al, 2019), due to different species possibly.Forty-seven annotated DEGs were identified in photosynthesis and Ros pathways between CKL and U3. Bar graph indicating the DEGs among the sets of CK_VS_CKL and CKL_VS_U3 (a).…”

“…Among these DEGs, most genes were down-regulated genes. Low temperatures could decrease level of Ros in study, in which results were inconsistent with Sharma(Sharma, Shahzad, Kumar, et al, 2019;Sharma, Shahzad, Rehman, et al, 2019), due to different species possibly.Forty-seven annotated DEGs were identified in photosynthesis and Ros pathways between CKL and U3. Among them, chloroplastic, peroxidase 2 and peroxidase 12, pyruvate, phosphate dikinase 2 isoform X1, peroxidase N OS = Armoracia rusticana, peroxisomal (S)-2-hydroxy-acid oxidase GLO3, peroxidase 52, peroxidase 21, and peroxidase 54 were significantly up-regulated.…”

“…The pathways were closely associated with low-temperature stress (Chen, Tian, et al, 2014;Chen, Song, et al, 2014;Sharma, Shahzad, Kumar, et al, 2019;Sharma, Shahzad, Rehman, et al, 2019;wang et al, 2018;Xu et al, 2014). The pathways were closely associated with low-temperature stress (Chen, Tian, et al, 2014;Chen, Song, et al, 2014;Sharma, Shahzad, Kumar, et al, 2019;Sharma, Shahzad, Rehman, et al, 2019;wang et al, 2018;Xu et al, 2014).…”

Stomatal and Photosynthetic Traits Are Associated with Investigating Sodium Chloride Tolerance of Brassica napus L. Cultivars

“…Apart from ion homeostasis, proline, and sugar accumulation is another well-known mechanism that has evolved in many plant species to overcome salt stress. The accumulation of sugars and proline in salt stress conditions protects the cells by balancing the osmotic strength of the cytosol with that of the vacuole and the external environment [51,52]. Furthermore, proline has a double role in enhancing salt-stress tolerance.…”

Exogenous Brassinolide Enhances the Growth and Cold Resistance of Maize (Zea mays L.) Seedlings under Chilling Stress

“…Liu [63] reported that BL treatment promoted the activity of antioxidant enzymes in Chorispora bungeana and increased the content of proline and glutathione under chilling stress, thereby eliminating excess ROS. More studies have shown that appropriate concentrations of BL can significantly increase antioxidant enzyme activity and increase antioxidant defense [20,[64][65][66]. However, after spraying three concentrations (T1, T2, T3) of BL solution onto two maize hybrids under chilling stress, the MDA content of the seedlings decreased significantly, and the antioxidant enzyme activity increased significantly.…”