Ascorbate–Glutathione Oxidant Scavengers, Metabolome Analysis and Adaptation Mechanisms of Ion Exclusion in Sorghum under Salt Stress

Abstract

Salt stress is one of the major significant restrictions that hamper plant development and agriculture ecosystems worldwide. Novel climate-adapted cultivars and stress tolerance-enhancing molecules are increasingly appreciated to mitigate the detrimental impacts of adverse stressful conditions. Sorghum is a valuable source of food and a potential model for exploring and understanding salt stress dynamics in cereals and for gaining a better understanding of their physiological pathways. Herein, we evaluate the antioxidant scavengers, photosynthetic regulation, and molecular mechanism of ion exclusion transporters in sorghum genotypes under saline conditions. A pot experiment was conducted in two sorghum genotypes viz. SSG 59-3 and PC-5 in a climate-controlled greenhouse under different salt concentrations (60, 80, 100, and 120 mM NaCl). Salinity drastically affected the photosynthetic machinery by reducing the accumulation of chlorophyll pigments and carotenoids. SSG 59-3 alleviated the adverse effects of salinity by suppressing oxidative stress (H2O2) and stimulating enzymatic and non-enzymatic antioxidant activities (SOD, APX, CAT, POD, GR, GST, DHAR, MDHAR, GSH, ASC, proline, GB), as well as protecting cell membrane integrity (MDA, electrolyte leakage). Salinity also influenced Na+ ion efflux and maintained a lower cytosolic Na+/K+ ratio via the concomitant upregulation of SbSOS1, SbSOS2, and SbNHX-2 and SbV-Ppase-II ion transporter genes in sorghum genotypes. Overall, these results suggest that Na+ ions were retained and detoxified, and less stress impact was observed in mature and younger leaves. Based on the above, we deciphered that SSG 59-3 performed better by retaining higher plant water status, photosynthetic assimilates and antioxidant potential, and the upregulation of ion transporter genes and may be utilized in the development of resistant sorghum lines in saline regions.

Glutathione Promotes Degradation and Metabolism of Residual Fungicides by Inducing UDP-Glycosyltransferase Genes in Tomato

“…The production of ROS production (H 2 O 2 and O 2 − ) in plant cells increased under stress. Studies have shown that glutathione can improve the salt tolerance of sorghum by scavenging ROS ( Punia et al, 2021 ). In addition, a study on upland cotton plants under lead (Pb) stress proved the importance of GSH in HMS detoxification ( Khan et al, 2016 ).…”

Integrated Metabolomics and Transcriptomics Analyses Highlight the Flavonoid Compounds Response to Alkaline Salt Stress in Glycyrrhiza uralensis Leaves

“…POD has a high affinity for its substrate H 2 O 2 and can clear H 2 O 2 and other hydroxyl free radicals . The enzyme system plays a crucial role in eliminating ROS, with the drastic increase in POD activity, being especially critical for maintaining the balance of active oxygen inside the body and reducing oxidative damage . Herein, after being subjected to alkaline salt stress, the SOD and CAT activities of G.…”

Integrated transcriptome and metabonomic analysis of key metabolic pathways in response to cadmium stress in novel buckwheat and cultivated species

“…Through the screening of metabolites, differentially accumulated metabolites (DAMs) with criteria FC>1.50, P-value<0.05 and VIP>1 were considered to determine the significant differences between samples (Punia et al, 2021). In DK19, compared with CK, 534 metabolites were up-regulated and 632 metabolites were downregulated after 7 days of treatment (Figure 4A).…”