Differential Impact of Nitric Oxide and Abscisic Acid on the Cellular and Physiological Functioning of sub1A QTL Bearing Rice Genotype under Salt Stress

Abstract

Hydroponic culture containing 200 mM NaCl was used to induce oxidative stress in seedlings of cultivars initially primed with 1 mM SNP and 10 µM ABA. Exogenous application of sodium nitroprusside (SNP – a nitric oxide donor) and abscisic acid (ABA) was well sensitized more in cv. Swarna Sub1 than cv. Swarna and also reflected in different cellular responses. The major effects of salinity, irrespective of the cultivar, were lowering the water relation, including relative water content and osmotic potential, and decreasing the compatible solutes like alanine, gamma-aminobutyric acid, and glycine betaine. The accumulated polyamines were reduced more in cv. Swarna with a concomitant decrease in photosynthetic reserves. NADP-malic enzyme activity, sucrose accumulation, ascorbate peroxidase, and glutathione S-transferase activities gradually declined under NaCl stress and the catabolizing enzymes like invertase (both wall and cytosolic forms) also declined. On the contrary, plants suffered from oxidative stress through superoxide, hydrogen peroxide, and their biosynthetic enzymes like NADP(H) oxidase. Moderation of Na+/K+ by both SNP and ABA were correlated with other salt sensitivities in the plants. The maximum effects of SNP and ABA were found in the recovery of antioxidation pathways, osmotic tolerance, and carbohydrate metabolism. Findings predict the efficacy of SNP and ABA either independently or cumulatively in overcoming NaCl toxicity in rice.

Exploring Aluminum Tolerance Mechanisms in Crops: A Comprehensive Review of Genetic, Metabolic, and Physiological Adaptations in Acidic Soils

“…The response to aluminum (Al) toxicity in plants involves two primary pathways: exclusion and oxidative tolerance [40]. Exclusion involves several channel proteins on cell membranes and tonoplasts, aided by specific metabolites, including anion transporters like malate/hydroxide ion that facilitate Al sequestration into vacuoles or apoplastic spaces [41]. Solubility of various organic acid anions like citrate, lactate, oxalate, and succinate in acidic environments also plays a role [42].…”

Exploring Aluminum Tolerance Mechanisms in Plants with Reference to Rice and Arabidopsis: A Comprehensive Review of Genetic, Metabolic, and Physiological Adaptations in Acidic Soils

“…The response to Al toxicity in plants involves two primary pathways: exclusion and oxidative tolerance [40]. Exclusion mechanisms involve several channel proteins on cell membranes and tonoplasts, including anion transporters (like malate/hydroxide ion), that facilitate Al sequestration into vacuoles or apoplastic spaces [41]. The solubility of various organic acid anions like citrate, lactate, oxalate, and succinate in acidic environments also plays a role [42].…”

Interaction between ABA and NO in plants under abiotic stresses and its regulatory mechanisms

“…The results suggest that ABA increases Pro level dependent on NO production under NaCl stress (Table 1). The application of ABA and NO can improve the growth of rice by maintaining water homeostasis, sodium ion/potassium ion (Na + /K + ) ratio, elevating antioxidant enzyme activities and antioxidant contents under 200 mM NaCl stress (Saha et al, 2022; Table 1). Hsu and Lee, 2018 reveal that methionine sulfoxide reductase (MSR; catalyzed the reduction of methionine sulfoxide to methionine residues and alleviated ROS damage to proteins)-related gene expression is up-regulated in rice roots under salt stress, but when 0.3 mM Flu or 300 mM cPTIO is added, the effect is reversed (Hsu and Lee, 2018;Table 2).…”

“…The results can be seen that NO acts cooperatively in ABA-induced antioxidant enzymes under salt tolerance. Using 200 mM NaCl-induced salt stress triggers the accumulation of H 2 O 2 and O 2 in rice, but when SNP and ABA are applied, these negative effects are reversed, following high levels of APX and glutathione S-transferase (GST, EC 2.5.1.18; Saha et al, 2022). Wu et al (2018) found that the concentrations of O 2 and MDA are increased in wheat seedlings under Mo condition, but these adverse effects can be relieved by exogenous ABA and SNP.…”

“…High levels of ROS lead to excessive oxidation of the plasma membrane, frequently producing high levels of malondialdehyde (MDA) and thiobarbituric acid reactive substances (TBARS), resulting in plant cell poisoning (Xu et al, 2013;Berni et al, 2019;Iqbal et al, 2022). To scavenge excess ROS, plants can regulate antioxidant enzymes, antioxidants, phytohormones, and signaling molecules in response to stress (Muneer et al, 2014;Peng et al, 2022;Saha et al, 2022). Moreover, abscisic acid (ABA) and nitric oxide (NO) significantly enhance antioxidant enzyme activities to eliminate excess ROS, thus increasing the survival percentage of maize seedlings under chilling stress (Li and Zhang, 2012).…”