Salt Tolerance Research Articles

Foliar application of esculin and digitoxin improve the yield quality of salt-stressed flax by improving the antioxidant defense system

BackgroundSecondary metabolites of several plants, including esculin and digitoxin, which are cardiac glycosides, were previously employed for their therapeutic effects. The current study aims to investigate the functions of the main Na+ /K+ transport inhibitor digitoxin and the antioxidant esculin for enhancing flax plant growth and production under salinity.MethodologyFlax plants were irrigated with distilled water supplemented with 0.0 and 5000 mg/L salt solution starting from 15 DAS from sowing. Then exogenous treatment with digitoxin and esculin with 50 mg L− 1 and 100 mg L− 1 were used for this work.ResultsAccording to the results of this work, foliar spraying of esculin or digitoxin increased the salinity tolerance of flax plants.The foliar application of either esculin or digitoxin induced an elevation in the contents of photosynthetic pigments, osmolytes including soluble sugar and proline as well as the total phenols in salt-stressed flax plants. Moreover, esculin and digitoxin in particular counteract oxidative stress by increasing the activity of antioxidant enzymes including superoxide dismutase, catalase, peroxidase, phenylalanine ammonia-lyase, and tyrosine ammonia lyase, leading to a decrease in reactive oxygen species and lipid peroxidation levels and electrolyte leakage. The efficiency of esculin and digitoxin to sustain ion homeostasis by inhibiting Na+ absorption and increasing potassium, calcium, and phosphorus in flax plants may be the reason for their protective actions towards salinity.As a consequence, esculin and digitoxin increased yield quantity and quality as shown by increases in all investigated yield criteriaas shoot height, root length, their fresh and dry weights as well asseed yield/plant (g), and 1000 seeds weight, especially those that improved the desired oil properties.ConclusionIn conclusion, this study concluded that digitoxin was more effective in inhibiting Na+ build-up and increasing flax salinity tolerance, particularly at the high investigated dose as compared to esculin. In this study, we reported the recent findings of exogenousapplication of either digitoxin or esculin glycosides which are new investigated salt alleviators never used before for improving the salt tolerance in flax plants.

Tannic Acid-Induced Polypyrrole Photothermal Coating for Efficient Solar-Driven Water Evaporation with Salt Resistance through the Roof-Structure Water Transfer Model

Tannic Acid-Induced Polypyrrole Photothermal Coating for Efficient Solar-Driven Water Evaporation with Salt Resistance through the Roof-Structure Water Transfer Model

Cakile maritima: A Halophyte Model to Study Salt Tolerance Mechanisms and Potential Useful Crop for Sustainable Saline Agriculture in the Context of Climate Change.

Salinity is an increasing problem for agriculture. Most plant species tolerate low or, at best, moderate soil salinities. However, a small (<1%) proportion of species, termed halophytes, can survive and complete their life cycle in natural habitats with salinities equivalent to 200 mM NaCl or more. Cakile maritima is a succulent annual halophyte belonging to the Brassicaceae family; it is dispersed worldwide and mainly grows in foreshores. Cakile maritima growth is optimal under slight (i.e., 100 mM NaCl) saline conditions, measured by biomass and seed production. Higher salt concentrations, up to 500 mM NaCl, significantly impact its growth but do not compromise its survival. Cakile maritima alleviates sodium toxicity through different strategies, including anatomical and morphological adaptations, ion transport regulation, biosynthesis of osmolytes, and activation of antioxidative mechanisms. The species is potentially useful as a cash crop for the so-called biosaline agriculture due to its production of secondary metabolites of medical and nutritional interest and the high oil accumulation in its seeds. In this review, we highlight the relevance of this species as a model for studying the basic mechanisms of salt tolerance and for sustainable biosaline agriculture in the context of soil salination and climate change.

Four MYB transcription factors regulate suberization and non-localized lignification at the root endodermis in rice.

In response to variable environments, rice (Oryza sativa) roots have developed lignified and suberized diffusion barriers at the endodermis to permit selective nutrient uptake for optimal growth. Here, we demonstrate that endodermal suberization and non-localized lignification are redundantly regulated by four MYB transcription factors: OsMYB39a, OsMYB41, OsMYB92a, and OsMYB92b. These transcription factors function downstream of the OsMYB36a/b/c, CASPARIAN STRIP INTEGRITY FACTOR (OsCIF)-SCHENGEN3 (OsSGN3), and stress-inducible signaling pathways in rice. Knockout of all four MYB genes resulted in the complete absence of endodermal suberin lamellae (SL) and almost no lignin deposition between the Casparian strip and the cortex-facing lignified band at cell corners under all conditions examined. In contrast, endodermis-specific overexpression of any of these MYB genes was sufficient to induce strong endodermal suberization and non-localized lignification near the root tip. Furthermore, OsMYB92a-overexpressing lines showed an altered ionomic profile and enhanced salinity tolerance. Transcriptome analysis identified 152 downstream genes regulated by OsMYB39a/41/92a/92b, including the key SL formation gene OsCYP86A1 and other genes involved in endodermal lignification and suberization under normal and stress conditions. Our results provide important insights into the molecular mechanisms underlying suberization and non-localized lignification at the root endodermis and their physiological significance in ion homeostasis and acclimation to environmental stress.

In Situ Growth of Well-Aligned MOF Nanoneedle Arrays into Composite Photothermal Membranes for Solar Desalination.

The solar-driven interfacial evaporation (SDIE) technology serves as a clean and facile approach combining seawater desalination to address water shortage and energy crisis. Recently, porous organic framework materials have aroused great attention, and the development of MOF-based composites with significant performance in photothermal conversion and water activation has become one of the important focuses in this field. In this work, an MOF-based composite photothermal membrane (PON@MOF) was prepared via the in situ growth of metal-organic framework (MOF) nanoneedle arrays induced by a pyridine-based organic polymer nanowire network (PON). The PON@MOF membrane possessed an MOF array layer, a PON-induced layer, and a porous support layer. The PON is rich in coordinated nitrogen atoms for anchoring the metal-ion source, and the main role of the PON layer is to provide favorable nucleation sites and orient in situ growth of well-aligned MOF nanoneedle arrays. With the highly conjugated framework of PON@MOF and the light trapping of the nanoarrays strengthening the photothermal conversion as well as the hydrophilic chemical structure facilitating the decrease of the water evaporation enthalpy, the PON@MOF membrane realizes highly efficient thermal vapor conversion. Under solar irradiation (1.0 kW m-2), PON@MOF demonstrated an evaporation rate of 2.14 kg m-2 h-1 and a solar-to-vapor conversion efficiency of 98.5%. Meanwhile, the PON@MOF membrane has excellent salt resistance and stability, highlighting its potential application in desalination. Overall, this work provides a special idea for the structural design of photothermal composites for solar desalination and freshwater production.

Effects of Salt Stress on Seed Germination and Embryo Growth of Oxytropis coerulea

Background: Oxytropis coerulea is considered to be an exceptional forage. The salinization of soil is a prevalent ecological issue worldwide. In order to study the effects of saline solution on seed germination and embryo growth of O. coerulea. Methods: An experiment was carried out using the culture dish filter paper method. Three salt stresses, namely, Na2CO3, NaCl and double salt were set, each of which was set to 0%, 0.3%, 0.6% and 0.9% concentration. Result: The results indicated that as the concentration of salt increased, there was a decrease in the germination rate, germination index and embryo growth. The activities of SOD, POD and CAT, as well as soluble protein content, initially increased and then decreased with increasing salt stress. The toxic effects of the three salts ranged from strong to weak as Na2CO3 greater than double salt greater than NaCl. The salt resistance indexes of 0.3% Na2CO3, NaCl and double salt were 53.87, 57.00 and 38.73, respectively and the salt resistance index of 0.6% NaCl was 50.21, indicating a high salt-tolerant degree. It showed certain resistance to 0.3% Na2CO3, 0.6% NaCl and 0.3% double salt. In short, the various soluble mechanisms of O. coerulea in different stages of salt stress and different salt stress levels have different reaction mechanisms, which reflect the salt stress of O. coerulea seeds. O. coerulea seeds can be planted in a suitable concentration of saline-alkali land, which can utilize the feed value and medicinal value of O. coerulea to improve economic benefits and utilize saline soil to improve the ecological environment.

Degradation of alkali‐activated Fe‐rich slag in magnesium sulfate solution

AbstractThe potential of Fe‐rich non‐ferrous metallurgical slag (NFMS) in alkali‐activated materials has been demonstrated, exhibiting promising mechanical strength and fire resistance. However, the durability of alkali‐activated NFMS (AA‐NFMS) in terms of sulfate salt resistance remains unexplored. Additionally, the variability in the chemical composition of NFMS presents challenges in directly assessing the durability of AA‐NFMS. This study investigates the interplay between the Ca/Si and Mg/Ca ratios in Fe‐rich NFMS and the resulting MgSO4 resistance of the AA‐NFMS made thereof. To do so, mass change and compressive strength retention were monitored for six months on AA‐NFMS immersed in 5 wt% MgSO4, whereas microstructure was investigated using scanning electron microscope (SEM) and electron probe microanalyzer (EPMA). The results show that the MgSO4 solution attacked selectively the reacted binder matrix of AA‐NFMS rather than the unreacted slag. The corrosion primarily occurs at the sulfate exposure surface of AA‐NFMS, forming a dense, thin layer of Mg(OH)2, which acts as a barrier and impedes further attack. Dissolution of Ca is the most pronounced among the major elements (Ca, Fe, Al, and Si) in the NFMS. The mass of the specimens increased linearly with the initial Ca content. The medium Ca concentration (∼10%) retained the highest strength.

A gene cluster for polyamine transport and modification improves salt tolerance in tomato.

Polyamines act as protective compounds directly protecting plants from stress-related damage, while also acting as signaling molecules to participate in serious abiotic stresses. However, the molecular mechanisms underlying these effects are poorly understood. Here, we utilized metabolome genome-wide association study to investigate the polyamine content of wild and cultivated tomato accessions, and we discovered a new gene cluster that drove polyamine content during tomato domestication. The gene cluster contains two polyphenol oxidases (SlPPOE and SlPPOF), two BAHD acyltransferases (SlAT4 and SlAT5), a coumaroyl-CoA ligase (Sl4CL6), and a polyamine uptake transporter (SlPUT3). SlPUT3 mediates polyamine uptake and transport, while the five other genes are involved in polyamine modification. Further salt tolerance assays demonstrated that SlPPOE, SlPPOF, and SlAT5 overexpression lines showed greater phenolamide accumulation and salt tolerance as compared with wild-type (WT). Meanwhile, the exogenous application of Spm to SlPUT3-OE lines displayed salt tolerance compared with WT, while having the opposite effect in slput3 lines, confirms that the polyamine and phenolamide can play a protective role by alleviating cell damage. SlPUT3 interacted with SlPIP2;4, a H2O2 transport protein, to maintain H2O2 homeostasis. Polyamine-derived H2O2 linked Spm to stress responses, suggesting that Spm signaling activates stress response pathways. Collectively, our finding reveals that the H2O2-polyamine-phenolamide module coordinately enhanced tomato salt stress tolerance and provide a foundation for tomato stress-resistance breeding.

Eco-friendly and easy-to-prepare three-dimensional network constructed by tannic acid/polypyrrole/sodium alginate via triple action mechanism of Fe3+ for highly-efficient solar evaporation

Solar-driven interfacial evaporation (SIE) represents a promising desalination technology leveraging solar energy and seawater. Nevertheless, the majority of SIE systems face constraints such as high costs, intricate fabrication processes, and limited tolerance to salt. Therein, we designed and developed an eco-friendly, simple, and low-cost way to construct independent and elastic three-dimensional networks using tannic acid (TA), polypyrrole (PPy), and sodium alginate (SA) via the triple action mechanism of Fe3+ for efficient water evaporation (TPS-x). When the mass ratios of PPy and TA are designed as 1:2, 1:1, 2:1, and 3:1, and crosslinked with sodium alginate and FeCl3, four composites (TPS-1, TPS-2, TPS-3, and TPS-4) are obtained, in which the light absorption and evaporation properties of TPS-3 are the optimal, with an evaporation rate up to 2.451 kg m−2 h−1 and a photothermal conversion efficiency up to 84.74 %. Additionally, the TPS-3 evaporator has excellent stability and salt tolerance, maintaining more than 95.5 % of its original evaporation rate after 20 days of cycling tests. Due to its exceptional photothermal evaporation performance, TPS-3 shows potential for practical commercial applications, particularly in the fields of wastewater treatment and desalination.

Biochemical and Transcriptomic Analyses Reveal Key Salinity and Alkalinity Stress Response and Tolerance Pathways in Salix linearistipularis Inoculated with Trichoderma

Soil salinization and alkalinization are pervasive environmental issues that severely restrict plant growth and crop yield. Utilizing plant growth-promoting rhizobacteria (PGPR) is an effective strategy to enhance plant tolerance to saline–alkaline stress, though the regulatory mechanisms remain unclear. This study employed biochemical and RNA-Seq methods to uncover the critical growth-promoting effects of Trichoderma spp. on Salix linearistipularis under saline–alkaline stress. The results showed that, during saline–alkaline stress, inoculation with Trichoderma sp. M4 and M5 significantly increased the proline and soluble sugar contents in Salix linearistipularis, enhanced the activities of SOD, POD, CAT, and APX, and reduced lipid peroxidation levels, with M4 exhibiting more pronounced effects than M5. RNA-Seq analysis of revealed that 11,051 genes were upregulated after Trichoderma sp. M4 inoculation under stress conditions, with 3532 genes primarily involved in carbon metabolism, amino acid biosynthesis, and oxidative phosphorylation—processes that alleviate saline–alkaline stress. Additionally, 7519 genes were uniquely upregulated by M4 under stress, mainly enriched in secondary metabolite biosynthesis, amino acid metabolism, cyanamide metabolism, and phenylpropanoid biosynthesis. M4 mitigates saline–alkaline stress-induced damage in Salix linearistipularis seedlings by reducing oxidative damage, enhancing organic acid and amino acid metabolism, and activating phenylpropanoid biosynthesis pathways to eliminate harmful ROS. This enhances the seedlings’ tolerance to saline–alkaline stress, providing a basis for studying fungi–plant interactions under such conditions.

Investigation of Nitrogen Removal in Flue Gas Desulfurization and Denitrification Wastewater Utilizing Halophilic Activated Sludge.

In the process of flue gas desulfurization and denitrification, the generation of high-sulfate wastewater containing nitrogen is a significant challenge for biological wastewater treatment. In this study, halophilic activated sludge was inoculated in a Sequencing Batch Reactor to remove nitrogen from wastewater with a high sulfate concentration (60 g/L). With the influent concentration of 180 mg/L, the removal rate of total nitrogen was more than 96.7%. The effluent ammonium nitrogen concentration was lower than 1.94 mg/L, and the effluent nitrate nitrogen and nitrite nitrogen concentrations were even lower than 0.77 mg/L. The salt tolerance of activated sludge is mainly related to the increase in the content of ectoine in microbial cells. The Specific Nitrite Oxidation Rate is quite low, while the Specific Nitrite Reduction Rate and Specific Nitrate Reduction Rate are relatively strong. In the system, there are various nitrogen metabolic processes, including aerobic nitrification, anaerobic denitrification, and simultaneous nitrification-denitrification processes. By analyzing the nitrogen metabolic mechanisms and microbial community structure of the reaction system, dominate bacteria can be identified, such as Azoarcus, Thauera, and Halomonas, which have significant nitrogen removal capabilities.

Diethyl aminoethyl hexanoate ameliorates salt tolerance associated with ion transport, osmotic adjustment, and metabolite reprograming in white clover

BackgroundSoil salinization is a serious environmental hazard, limiting plant growth and production in different agro-ecological zones worldwide. Diethyl aminoethyl hexanoate (DA-6) as an essential plant growth regulator (PGR) exhibits a beneficial role in improving crop growth and stress tolerance. However, the DA-6-regulated effect and mechanism of salt tolerance in plants are still not fully understood. The objective of current study was to disclose salt tolerance induced by DA-6 in relation to changes in water and redox balance, photosynthetic function, ionic homeostasis, and organic metabolites reprogramming in white clover (Trifolium repens).ResultsA prolonged duration of salt stress caused water loss, impaired photosynthetic function, and oxidative injury to plants. However, foliar application of DA-6 significantly improved osmotic adjustment (OA), photochemical efficiency, and cell membrane stability under salt stress. In addition, high salinity induced massive accumulation of sodium (Na), but decreased accumulation of potassium (K) in leaves and roots of all plants. DA-6-treated plants demonstrated significantly higher transcript levels of genes involved in uptake and transport of Na and K such as VP1, HKT8, SOS1, NHX2, NHX6, and SKOR in leaves as well as VP1, HKT1, HKT8, H+-ATPase, TPK5, SOS1, NHX2, and SKOR in roots. Metabolomics analysis further illustrated that DA-6 primarily induced the accumulation of glucuronic acid, hexanoic acid, linolenic acid, arachidonic acid, inosose, erythrulose, galactopyranose, talopyranose, urea, 1-monopalmitin, glycerol monostearate, campesterol, stigmasterol, and alanine.ConclusionsThe DA-6 significantly up-regulated transcript levels of multiple genes associated with increased Na+ compartmentalization in vacuoles and Na+ sequestration in roots to reduce Na+ transport to photosynthetic organs, thereby maintaining Na+ homeostasis under salt stress. The accumulation of many organic metabolites induced by the DA-6 could be attributed to enhanced cell wall and membrane structural stability and functionality, OA, antioxidant defense, and downstream signal transduction in leaves under salt stress. The present study provides a deep insight about the synergistic role of DA-6 in salt tolerance of white clover.

Ultra‐Durable Solar‐Driven Seawater Electrolysis for Sustainable Hydrogen Production

AbstractIons in seawater hinder direct sewage electrolysis due to the extreme corrosion of Cl− to the anode and reaction of Mg2+ and Ca2+ on the cathode producing solid substances, which reduce the electrolytic efficiency. However, traditional desalination consuming fossil fuel with massive CO2 emissions threatens human survival. Therefore, zero‐carbon emission, ultra‐durable, large‐scale production of freshwater from seawater for water electrolysis is urgently needed. Herein, a multifunctional system for seawater is demonstrated electrolysis based on ultra‐durable solar desalination outdoors. The solar evaporators reach an evaporation flux of 1.88 kg m−2 h−1 with a photothermal conversion efficiency of solar energy as high as 91.3% with excellent ultra‐durable salt resistance even for saturated saltwater due to the Marangoni effects. Moreover, the condensation of pure water from solar desalination based on the evaporation system reaches 0.54 L m−2 h−1 outdoors, which is suitable for a 20 cm × 20 cm engineered electrode equipped with a Janus membrane powered by a solar panel to produce H2 outdoors. The ultrafast unidirectional transport of H2 bubbles enabled by Janus membranes can greatly improve the H2 production efficiency at a rate approaching 85 mL h−1 for continuous 24 h outdoors.

Understanding of Plant Salt Tolerance Mechanisms and Application to Molecular Breeding.

Soil salinization is a widespread hindrance that endangers agricultural production and ecological security. High salt concentrations in saline soils are primarily caused by osmotic stress, ionic toxicity and oxidative stress, which have a negative impact on plant growth and development. In order to withstand salt stress, plants have developed a series of complicated physiological and molecular mechanisms, encompassing adaptive changes in the structure and function of various plant organs, as well as the intricate signal transduction networks enabling plants to survive in high-salinity environments. This review summarizes the recent advances in salt perception under different tissues, physiological responses and signaling regulations of plant tolerance to salt stress. We also examine the current knowledge of strategies for breeding salt-tolerant plants, including the applications of omics technologies and transgenic approaches, aiming to provide the basis for the cultivation of salt-tolerant crops through molecular breeding. Finally, future research on the application of wild germplasm resources and muti-omics technologies to discover new tolerant genes as well as investigation of crosstalk among plant hormone signaling pathways to uncover plant salt tolerance mechanisms are also discussed in this review.

Exogenous Melatonin Reinforces Photosynthesis, Antioxidant Defense and Gene Expression to Ameliorate Na2CO3 Stress in Maize.

Salt stress can seriously affect the growth and development of maize (Zea mays L.), resulting in a great yield loss. Melatonin (MT), an indole hormone, is a potential enhancer of plant tolerance against salt stress. However, the complex mechanisms of MT application in enhancing maize salt tolerance are still unclear. Herein, three-leaf seedlings of salt-susceptible P138 and its salt-resistant ethyl methane sulfonate (EMS)-104 mutant were cultured with or without 150 μM MT application under 0 and 100 mM Na2CO3 treatments for seven days, to systematically explore the response mechanisms of exogenous MT in improving the salt tolerance of maize. The results showed that salt stress triggered an escalation in reactive oxygen species production, enhanced multiple antioxidant enzymes' activities, impaired cellular membrane permeability, inhibited photosynthetic pigment accumulation, and ultimately undermined the vigor and photosynthetic prowess of the seedlings. While suitable MT application counteracted the detrimental impacts of Na2CO3 on seedlings' growth and photosynthetic capacity, the seedling length and net photosynthetic rate of P138 and EMS-104 were increased by 5.5% and 18.7%, and 12.7% and 54.5%, respectively. Quantitative real-time PCR (qRT-PCR) analysis further showed that MT application activated the expression levels of antioxidant enzyme-related genes (Zm00001d025106, Zm00001d031908, Zm00001d027511, and Zm00001d040364) and pigment biosynthesis-related genes (Zm00001d011819 and Zm00001d017766) in both maize seedlings under Na2CO3 stress; they then formed a complex interaction network of gene expression, multiple physiological metabolisms, and phenotype changes to influence the salt tolerance of maize seedlings under MT or Na2CO3 stress. To sum up, these observations underscore that 150 μM MT can alleviate salt injury of maize seedlings, which may provide new insights for further investigating MT regulation mechanisms to enhance maize seedlings' salt resistance.

The amino acid permease SlAAP6 contributes to tomato growth and salt tolerance by mediating branched-chain amino acid transport

The amino acid permease <i>SlAAP6</i> contributes to tomato growth and salt tolerance by mediating branched-chain amino acid transport

The Maize Gene ZmGLYI-8 Confers Salt and Drought Tolerance in Transgenic Arabidopsis Plants.

Methylglyoxal (MG), a highly reactive and cytotoxic α-oxoaldehyde compound, can over-accumulate under abiotic stress, consequently injuring plants or even causing death. Glyoxalase I (GLYI), the first enzyme of the glyoxalase pathway, plays multiple roles in the detoxification of MG and in abiotic stress responses. However, the GLY1 gene in maize has been little studied in response to abiotic stress. In this study, we screened a glyoxalase I gene (ZmGLYI-8) and overexpressed in Arabidopsis. This gene was localized in the cytoplasm and can be induced in maize seedlings under multiple stress treatments, including salt, drought, MG, ABA, H2O2 and high temperature stress. Phenotypic analysis revealed that after MG, salt and drought stress treatments, overexpression of ZmGLYI-8 increased the tolerance of transgenic Arabidopsis to MG, salt and drought stress. Furthermore, we demonstrated that the overexpression of ZmGLYI-8 scavenges accumulated reactive oxygen species, detoxifies MG and enhances the activity of antioxidant enzymes to improve the resistance of transgenic Arabidopsis plants to salt and drought stress. In summary, this study preliminarily elucidates the molecular mechanism of the maize ZmGLYI-8 gene in transgenic Arabidopsis and provides new insight into the breeding of salt- and drought-tolerant maize varieties.

Silicon (Si) enhances salt tolerance in sea barley (Hordeum marinum) by promoting growth, detoxifying reactive oxygen species, and stimulating antioxidant defense mechanisms

Silicon (Si) enhances salt tolerance in sea barley (Hordeum marinum) by promoting growth, detoxifying reactive oxygen species, and stimulating antioxidant defense mechanisms

AtC3H3, an Arabidopsis Non-TZF Gene, Enhances Salt Tolerance by Increasing the Expression of Both ABA-Dependent and -Independent Stress-Responsive Genes.

Salinity causes widespread crop loss and prompts plants to adapt through changes in gene expression. In this study, we aimed to investigate the function of the non-tandem CCCH zinc-finger (non-TZF) protein gene AtC3H3 in response to salt stress in Arabidopsis. AtC3H3, a gene from the non-TZF gene family known for its RNA-binding and RNase activities, was up-regulated under osmotic stress, such as high salt and drought. When overexpressed in Arabidopsis, AtC3H3 improved tolerance to salt stress, but not drought stress. The expression of well-known abscisic acid (ABA)-dependent salt stress-responsive genes, namely Responsive to Desiccation 29B (RD29B), RD22, and Responsive to ABA 18 (RAB18), and representative ABA-independent salt stress-responsive genes, namely Dehydration-Responsive Element Binding protein 2A (DREB2A) and DREB2B, was significantly higher in AtC3H3-overexpressing transgenic plants (AtC3H3 OXs) than in wild-type plants (WT) under NaCl treatment, indicating its significance in both ABA-dependent and -independent signal transduction pathways. mRNA-sequencing (mRNA-Seq) analysis using NaCl-treated WT and AtC3H3 OXs revealed no potential target mRNAs for the RNase function of AtC3H3, suggesting that the potential targets of AtC3H3 might be noncoding RNAs and not mRNAs. Through this study, we conclusively demonstrated that AtC3H3 plays a crucial role in salt stress tolerance by influencing the expression of salt stress-responsive genes. These findings offer new insights into plant stress response mechanisms and suggest potential strategies for improving crop resilience to salinity stress.

Marker-Assisted Selection of Jacalin-Related Lectin Genes OsJRL45 and OsJRL40 Derived from Sea Rice 86 Enhances Salt Tolerance in Rice.

Soil salinization limits rice growth and is an important restriction on grain yield. Jacalin-related lectins are involved in multiple stress responses, but their role in salt stress responses and use as molecular markers for salt tolerance remain poorly understood. Salt stress treatments and RT-qPCR analyses of Sea Rice 86 (SR86), 9311, and Nipponbare (Nip) showed that OsJRL45 and OsJRL40 enhanced tolerance of salt stress in SR86. Molecular markers based on sequence differences in SR86 and the salt-sensitive variety, 9311, in the intergenic region between OsJRL45 and OsJRL40 were validated in recombinant inbred lines derived from SR86 and 9311, hybrid populations, and common rice varieties. Yeast two-hybrid and bimolecular fluorescence complementation demonstrated that OsJRL45 and OsJRL40 interacted. Co-transformation of Nip with OsJRL45 and OsJRL40 derived from SR86 had no effect on the mature phenotype in T2 plants; however, salt stress at the three-leaf stage led to significant increases in CAT, POD, SOD, and Pro contents, but reduced MDA content in transgenic plants. Transcriptomic analysis identified 834 differentially expressed genes in transgenic plants under salt stress. GO and KEGG enrichment analyses indicated that metabolic pathways related to antioxidant responses and osmotic balance were crucial for salt-stress tolerance. Thus, molecular markers based on nucleotide differences in OsJRL45 and OsJRL40 provide a novel method for identifying salt-tolerant rice varieties.