Search Results (1,805)

Alhagi camelorum is a dominant leguminous shrub distributed in the Taklamakan Desert, an area characterized by extreme drought and high soil salinization, which can complete its life cycle normally in salt-affected soils. However, the underlying molecular regulatory mechanism of its salt tolerance remains largely unclear. The AcABI5 gene was successfully cloned and characterized, and it encodes a typical nuclear-localized bZIP transcription factor. Functional characterization demonstrated that overexpression of AcABI5 markedly improved the salt stress tolerance of A. camelorum calli, whereas silencing of AcABI5 via virus-induced gene silencing (VIGS) rendered the plant more sensitive to salt stress. Further mechanistic investigations revealed that AcABI5 enhanced salt tolerance by regulating the expression of superoxide dismutase (SOD)- and peroxidase (POD)-related antioxidant genes. Compared with the wild type, AcABI5-overexpressing calli exhibited significantly increased SOD and POD activities and remarkably reduced malondialdehyde (MDA) content under salt treatment, whereas AcABI5-silenced lines exhibited the opposite physiological phenotypes. Furthermore, heterologous silencing of AcABI5 in Nicotiana benthamiana via virus-induced gene silencing (VIGS) produced comparable salt-sensitive phenotypes, similar to those observed in A. camelorum AcABI5-silenced lines. Collectively, these results provide insights into the molecular mechanism by which AcABI5 enhances salt tolerance in A. camelorum, and lay a solid theoretical foundation for the optimization of the A. camelorum genetic transformation system and the expansion of related salt-tolerant crop research. Full article

Saline–alkali stress severely limits crop production worldwide. Soybean [Glycine max (L.) Merr.] is particularly sensitive during seed germination, a stage critical for stand establishment. This complex stress environment encompasses two distinct yet equally critical dimensions: neutral salt stress and alkaline salt stress, each eliciting specialized physiological and metabolic responses. Here, a comparative assessment of four genotypes (tolerant: CN16, CN17; sensitive: Williams 82, K18) under 100 mmol/L Na⁺ revealed that alkaline salt stress exerts a significantly more potent inhibitory effect than neutral salt stress. Tolerant cultivars maintained 75–80% germination under alkaline conditions, whereas sensitive ones dropped below 15%, a divergence primarily driven by superior oxidative mitigation capacity. Integrated multi-omics analysis of the tolerant variety CN16 identified stage-specific regulatory shifts: early alkaline salt stress (60 h) triggers extensive transcriptional reprogramming focused on physical barrier reinforcement, including cell walls and lipid remodeling. By 96 h, regulatory modes between the two stress types diverged: neutral salt elicited a transcriptional surge, while alkaline salt transitioned to a metabolically dominant regulation, shifting flux from growth-related isoflavonoids to defense-related anthocyanins. Crucially, this study uncovers the distinct bioenergetic trade-offs governing these responses: whereas adaptation to neutral salt relies on low-energy galactose metabolism, tolerance to alkaline salt demands energy-intensive processes, specifically the active vacuolar compartmentalization of organic acids and anthocyanins for intracellular buffering. This obligatory energy expenditure restricts biomass accumulation, explaining the severe growth penalties observed in complex saline-alkali environments. Finally, the identification of a core regulatory module driven by key genes, including GmPHOT2b, GmLOG, and GmSHMT08, enriches the metabolic regulatory network under saline-alkali stress, providing core targets and a theoretical framework for precisely balancing metabolic expenditure with biomass accumulation in breeding practice. Full article

The multi-cycle high-rate injection and production operations in Underground Gas Storage (UGS) facilities converted from depleted fracture-pore carbonate gas reservoirs induce complex rock–fluid interactions that threaten long-term integrity and performance. This study experimentally investigates the petrophysical responses of the Xiangguosi (XGS) UGS carbonate reservoirs in China using multi-cycle stress sensitivity tests, fines migration experiments, and water evaporation–salt precipitation analyses. SEM observations distinguish the contributions of crack closure and matrix compression to permeability evolution. Results show a sharp contrast in mechanical damage: high-quality rocks present negligible permanent deformation (<8% Young’s modulus reduction), whereas poor-quality rocks suffer catastrophic deterioration (>60%). Fines migration exhibits a three-stage behavior under cyclic flow, with water saturation significantly aggravating permeability impairment. A critical salinity threshold (220,000 ppm) is identified for the transition between drying-enhanced storage and salt plugging. Permeability declines sharply despite a slight porosity increase due to selective salt clogging of key pore throats, revealing a clear porosity–permeability decoupling. Salt deposition under movable water conditions can reduce UGS capacity by up to 1.45%. Reservoir heterogeneity, microfractures, karst structures, and initial petrophysical properties dominate the storage and flow space evolution. This work provides a predictive framework for optimizing injection–production strategies and improving the performance of complex carbonate UGS. Full article

Salt cavern CO₂ storage (SCCS) technology represents a crucial pathway for achieving large-scale carbon sequestration. However, its long-term operation faces the challenge of cavern shrinkage due to surrounding rock creep, which directly impacts storage safety and stability. Despite its importance, there is currently a lack of research focusing on the proactive control of SCCS cavern shrinkage and its collaborative optimization with operational economy. To fill this gap, this paper first investigated the effects of the stress state (f₁), height-to-diameter ratio (f₂), symmetry factor (f₃), and cavern volume (f₄) on the volumetric shrinkage rate through numerical simulations of regular caverns and univariate sensitivity analysis. The sensitivity ranking and quantitative relationships of these factors were clarified as $f_1(2.31)>f_4(0.309)>f_2(0.166)>f_3(0)$. Subsequently, a multi-objective nonlinear optimization model was established, and the primal-dual interior-point method was adopted as the solution algorithm. Using actual cavern data as a case study for the solution, the results demonstrate that the optimization model converges stably in approximately 1.1 s. The resulting optimal gas injection allocation scheme achieves a 14.77% improvement in the comprehensive score compared to the baseline scheme. This study provides a theoretical basis and a practical tool for the rapid generation of SCCS gas injection allocation schemes. Full article

This study examined the toxicological, and bioaccumulative effects of dietary lead (Pb) on Tenebrio molitor larvae, increasingly considered for human and animal consumption within sustainable food and feed production systems. Larvae were exposed for 21 days to an oat-based diet contaminated with lead salts (125–2000 mg Pb/kg). Body mass, and Pb accumulation in the intestine, internal tissues, and cuticle were analyzed. Pb concentrations in larval compartments increased with increasing nominal Pb levels in feed, with concentrations in internal tissues and cuticle reaching 5–6 times higher than in the control. Estimated bioaccumulation factors (BAF) were below 1 in all cases, indicating no biomagnification. Despite high exposure levels, no significant effects on larval survival or biomass gain were observed. These findings indicate that growth-related parameters are not sensitive indicators of Pb exposure. At the same time, substantial Pb accumulation occurred, particularly in the gut and cuticle, highlighting a risk of “hidden” contamination in insect-based production systems. The results emphasize the need for substrate monitoring and the inclusion of sensitive chemical indicators in food safety risk assessment. Full article

Citrus production is increasingly constrained worldwide by rising soil salinity, particularly in arid and semi-arid regions. In Tunisia, the expansion of saline soils represents a major abiotic stress limiting orchard productivity. The identification of salt-tolerant rootstocks has therefore become a priority, especially as alternatives to sour orange (SO, Citrus aurantium L.), which is highly susceptible to Citrus tristeza virus. In recent years, several outbreaks of the disease have been reported in the Cap Bon citrus-growing region, posing an imminent threat to the sustainability of citrus production in Tunisia. This study evaluated the salt tolerance of commercial cultivars (HER, MAR, WN, NH) grafted onto Citrus volkameriana Ten. & Pasq. (CV, Citrus aurantium × Citrus limon (L.) Burm.f.) and three Poncirus trifoliata hybrids (CC, C35, CTR) under irrigation water salinity ranging from 1.1 to 4.1 mS/cm and soil salinity between 1.8 and 3.8 mS/cm. Data were collected between 2020 and 2021 in five young citrus orchards (KHB, OSN, BKN, BSJ, CHK) located in the main citrus-producing region of Tunisia, with key physiological measurements conducted during the high-evaporation period. Salinity increased across most sites during summer 2021, affecting ion homeostasis, Na⁺/K⁺ selectivity, stomatal traits, photosynthetic performance, and growth. The highest leaf Cl⁻ concentration (0.4 meq g⁻¹ dry weight) was recorded in the sensitive HER/CC combination at the OSN site. Increased salinity at OSN was associated with a 0.86% reduction in canopy growth compared to BSJ. Rootstock tolerance was strongly linked to the ability to restrict Cl⁻ accumulation in leaf tissues. Under higher salinity conditions, CV showed superior performance and represents a suitable alternative to SO. Full article

Background: High dietary salt intake has been implicated in immune-mediated inflammatory diseases; however, its impact on allergic contact dermatitis (ACD) remains unclear. This study examined whether dietary salt exposure during the sensitization phase influences the severity of DNFB-induced ACD in mice. Methods: Female C57BL/6N mice were fed a normal diet (ND) or an 8% high-salt diet (HSD). In a subset, salt intake was normalized prior to sensitization (HSD → ND). ACD was induced using a DNFB sensitization and challenge protocol. Ear swelling was quantified using incremental area under the curve (iAUC). Histological analyses and measurements of plasma and skin sodium were performed. Results: HSD-fed mice showed greater ear swelling and higher iAUC than ND controls, accompanied by enhanced inflammatory cell infiltration. Skin sodium concentration differed among groups, with a higher concentration in HSD-fed mice compared that in the HSD → ND group. Normalization of salt intake prior to sensitization attenuated disease severity. Spearman analyses indicated that total sodium intake and plasma potassium concentration were associated with inflammatory severity. Conclusions: Dietary salt exposure during immune sensitization exacerbated experimental ACD and was associated with systemic electrolyte alterations. These findings suggest that sodium exposure during immune activation may influence allergic skin inflammation. Full article

Soil salinization in arid oases constrains soil functioning and crop production, making spatially explicit monitoring important for land management. Multispectral optical remote sensing enables large-area salinity assessment, but in oasis environments such as the Keriya Oasis, its performance can be limited by spectral confusion between salt crusts and bright bare soils, sparse vegetation cover, and strong surface heterogeneity. Synthetic aperture radar (SAR), by contrast, provides all-weather imaging capability and sensitivity to surface scattering and dielectric-related conditions, but its salinity interpretation is often affected by surface complexity and environmental coupling. To address these, a spectral index–polarimetric scattering integration framework that combines RADARSAT-2 and Landsat-8 OLI features within a simple two-dimensional (2D) feature space was developed. Two groups of models were constructed from variables selected through a data-driven screening process: (1) polarimetric feature space models based on combinations such as VanZyl volume scattering with Pauli odd-bounce or Touzi alpha scattering; and (2) multi-source feature space models that integrate the optimal polarimetric component with key spectral indicators such as SI4 and MSAVI. Among all tested models, VanZyl_vol-SI4 achieved the best performance (fitting: R² = 0.749, RMSE = 5.798 dS m⁻¹, MAE = 4.086 dS m⁻¹; validation: R² = 0.716, RMSE = 5.566 dS m⁻¹, MAE = 4.528 dS m⁻¹). The results indicate that integrating PolSAR scattering information with optical indices can improve salinity mapping relative to single-source feature spaces in the Keriya Oasis. The proposed 2D framework provides a concise way to compare different feature combinations and supports regional identification of salt-affected soils. Full article

Polyhalite, K₂SO₄•MgSO₄•2CaSO₄•2H₂O, a ternary evaporite mineral, is commonly found in evaporitic rock salt strata, where it acts as an indicator mineral for potash evaporite deposits. As a directly exploitable mineral potash fertilizer, polyhalite serves as an important substitute for potassium resources. The thermodynamic properties of polyhalite remain poorly characterized experimentally; consequently, current estimates predominantly rely on predictive modeling and indirect experimental approaches. The Raman spectra of free SO₄²⁻ vibrational modes in various sulfate minerals are sensitive to the local symmetry and hydrogen-bonding environment within crystal hydrates, and are directly influenced by the surrounding crystal field. This sensitivity makes Raman spectroscopy a powerful tool for investigating and identifying the crystal structures of sulfate minerals. In this work, the thermodynamic and Raman vibrational properties of polyhalite were investigated using density functional theory (DFT). Phonon calculations at the optimized geometry were employed to compute polyhalite’s key thermodynamic properties—specific heat, entropy, enthalpy, Gibbs free energy, and Debye temperature—over a temperature range of 0–1000 K. The results showed that: (1) the computed volume exhibited minimal error, approximately 0.87%, compared to experimental data; (2) the calculated values for the isobaric heat capacity and entropy were 420.72 and 531.39 J·mol⁻¹·K⁻¹ at 298.15 K, respectively; and (3) the calculated value for the free energy of formation at 298.15 K was −5670 kJ·mol⁻¹. The computed Raman spectrum results showed that the typical spectral features of polyhalite are: (1) ν1 for 1024 cm⁻¹, symmetric stretching mode; (2) ν2 for 464 cm⁻¹, symmetry bending mode; and (3) ν4 for 627 cm⁻¹, anti-symmetry bending mode. Full article

Elm (Ulmus pumila), an ecologically and economically valuable tree, exhibits significant tolerance to abiotic stress. However, the physiological and molecular mechanisms underlying its stress adaptabilities are largely unknown. Here, two elm salt-tolerant cultivars (ST-Y and ST-Q) and two salt-sensitive cultivars (SS-J and SS-JX) were identified in the 13 elm accessions collected from Shandong province, China via phenotypic salt tolerance screening. The key salt tolerance mechanisms were explored in ST-Y and SS-J via transcriptomic (RNA-Seq) assays, and subsequently validated in ST-Q and SS-JX via quantitative real-time polymerase chain reaction (RT-qPCR) analyses. Under salt treatment, ST-Y maintained leaf intactness and enhanced activation of antioxidant enzymes with a reduction in reactive oxygen species (ROS) accumulation, while SS-J suffered leaf defoliation and showed compromised antioxidant capacity with higher ROS levels. KEGG pathway analysis revealed that ST-Y leaves exhibited a unique enrichment of differentially expressed genes (DEGs) in the “oxidative phosphorylation (OXPHOS)” pathway after salt stress treatment. Both ST-Y and SS-J exhibited significant enrichment in the “metabolic pathway”, but the number of DEGs in the “arachidonic acid (AA) metabolism” pathway was much higher in ST-Y than in SS-J. Further RT-qPCR analysis verified the accuracy of the RNA-Seq data and revealed that genes related to the “OXPHOS” pathway were significantly up-regulated in ST-Y and ST-Q, but down-regulated in SS-J and SS-JX. Our results suggested that OXPHOS efficiency is critical to antioxidant capacity in elm salt tolerance, suggesting new avenues for forest tree improvement for climate change. Full article

In the current study, the dielectric behavior of ternary mixtures composed of glycerol and water with various salt additives is investigated over a frequency range that extends from 0.5 to 20 GHz and at temperatures between 5 and 55 °C. The investigated mixtures consisted of glycerol and water with glycerol volume ratios of 20%, 40%, and 60%. To explore the salt addition’s effect on the dielectric properties, different moderate ionic strengths of glycerol–water mixtures were prepared with NaCl concentrations of 0.10, 0.20, and 0.30 M for the same glycerol volume ratios. The ion-specific effects on the dielectric properties were investigated for prepared mixtures with a 0.10 M concentration of Na₂SO₃, NaNO₃, and KCl for the 20% glycerol ratio to explore ions with different charge density and hydration tendencies. Using dielectric spectroscopy, the frequency dependence of the real (${\epsilon }^{\prime }$) and imaginary (${\epsilon }^{″}$) dielectric constants was measured, and the associated dielectric parameters were extracted using the Cole–Cole model. This study shows that increasing the salt concentration results in a slight decrease in ${\epsilon }^{\prime }$ while ${\epsilon }^{″}$ increases dramatically, especially at lower frequencies, due to enhanced DC conductivity. An isopermittivity behavior is observed in ${\epsilon }^{\prime }$ as the temperature changes across all mixtures, and it is found to be insensitive to the addition of salt, indicating that it is mainly dictated by the glycerol–water dipolar relaxation network. Among the tested mixtures is the 20% glycerol mixture with 0.10 M KCl, which exhibits the highest ${\epsilon }^{″}$ value in the low-frequency range, attributed to its relatively high DC conductivity. Additionally, the dielectric properties of mixtures with higher glycerol ratios are found to be less sensitive to the addition of salt due to their high viscosity and the higher structured solvent network, which collectively limit ionic mobility and suppress changes in dielectric response. Full article

The Fruit Weight 2.2-like (FWL) gene family, characterized by the conserved PLAC8 domain, plays important roles in plant organ development and metal ion homeostasis. However, the systematic characterization of FWL genes in rice (Oryza sativa) and their involvement in abiotic stress responses remain insufficiently understood. In this study, a genome-wide identification of the FWL gene family in rice was performed, resulting in the identification of nine OsFWL genes, including a previously unreported member, OsFWL9. Phylogenetic analysis of FWL proteins from rice, maize, soybean, and Arabidopsis thaliana classified the family into three distinct subgroups, indicating both conserved and divergent evolutionary relationships. Structural and conserved motif analyses revealed that OsFWL proteins share similar domain architectures, while promoter analysis uncovered abundant cis-acting elements associated with stress responses, phytohormone signaling, and plant growth and development. Expression profiling demonstrated that most OsFWL genes were rapidly induced by drought, high temperature, salt, and arsenic stresses at the seedling stage, suggesting their broad involvement in abiotic stress adaptation. Notably, OsFWL8 exhibited a unique expression pattern, being significantly suppressed under arsenic stress. Functional characterization using CRISPR/Cas9-generated knockout mutants and overexpression lines revealed that OsFWL8 negatively regulates arsenic tolerance in rice. Overexpression of OsFWL8 markedly increased plant sensitivity to arsenic stress. Furthermore, arsenic detoxification-related genes, including OsABCC1 and OsPCS2, were significantly upregulated in fwl8 mutants under arsenic treatment. These results indicate that OsFWL8 may modulate arsenic tolerance by influencing arsenic sequestration and detoxification pathways. Overall, this study provides a comprehensive overview of the FWL gene family in rice and identifies OsFWL8 as a key regulator of arsenic stress response, offering valuable insights for improving rice tolerance to heavy metal stress. Full article

This study investigates how soil calcium (Ca) and magnesium (Mg) supplementation influence mitragynine accumulation in Mitragyna speciosa (kratom), addressing the lack of quantitative thresholds in previous research. Seedlings from a uniform seed stock were cultivated in a controlled environment using a standardized soil mix (soil:peat moss:earthworm castings, 6:1:1). Following an initial growth phase, Ca and Mg were applied at three concentrations and in fixed Ca:Mg ratios (5:1, 10:1, 20:1) using gypsum and Epsom salt. Over a 45-day treatment period, growth parameters and mitragynine levels were assessed one week after the final application. Seedlings under control had the highest total biomass (102.35 g), significantly exceeding both the Mg-only and Ca:Mg treatments (64–84 g), and values above the typical upper threshold of 20 did not suppress growth, as evidenced by unchanged root-to-shoot ratios across treatments. In contrast, mitragynine accumulation was the highest under moderate Ca:Mg ratios (8–10), exhibiting a 2–14% increase relative to the control, suggesting that production of this alkaloid is more sensitive to nutrient balance than overall growth. These findings underscore the importance of nutrient ratios, rather than individual nutrient concentrations, in regulating both vegetative development and alkaloid production in kratom. Maintaining an appropriate Ca:Mg ratio can support efficient seedling growth as well as maximizing mitragynine levels. Preliminary field trials over a span of one month indicate that field-grown seedlings exhibit a similar result with high growth and mitragynine content in soils having a Ca:Mg ratio of 1:10. Future studies should test these responses under field conditions and over longer growth periods. Full article

Hybrid desalination systems that combine osmotic and thermal driving forces offer a promising route to improve water recovery and energy efficiency for high-salinity feedwaters where conventional processes face limitations. This study presents a comprehensive mathematical modeling framework and performance analysis of a hybrid forward osmosis–membrane distillation (FO-MD) system for seawater desalination. The novel contributions include: (1) a coupled heat, mass, and solute transport model that explicitly accounts for concentration polarization, temperature polarization, reverse salt flux, and their dynamic interactions through the draw solution loop; (2) a quantitative assessment of the synergistic regeneration effect, showing how MD maintains draw solution concentration and stabilizes FO performance over time; (3) systematic evaluation of parameter sensitivity to polarization effects; and (4) comparative energy analysis quantifying specific energy consumption relative to standalone processes. Model predictions were validated against published experimental data, showing good agreement for both FO and MD fluxes (R² > 0.94). The MD flux increased from approximately 2–3 LMH at 30 °C to 17 LMH at 50 °C, confirming vapor pressure enhancement. FO water flux increased significantly with draw solution concentration from 0.2 to 1.1 M due to higher osmotic pressure differences. Time-dependent simulations of the integrated FO-MD system showed that MD regeneration reduces draw solution dilution by 60% compared to standalone FO, maintaining FO flux approximately 43% higher after 6 h of operation. Sensitivity analysis revealed that FO predictions are moderately sensitive to mass transfer coefficients (6–9% flux change for 20% parameter variation), while MD shows lower sensitivity to heat transfer coefficients (3–5%). Energy analysis indicates that FO-MD hybridization reduces thermal energy consumption by 15–40% compared to standalone MD, with specific energy consumption of 382 kWh/m³ (40.2 kWh/m³ primary energy equivalent) when using low-grade heat. The obtained results demonstrate that FO-MD hybridization enhances water recovery and operational stability compared to standalone processes, supporting its potential for energy-efficient desalination of high-salinity brines and industrial wastewaters where low-grade heat is available. Full article

Salt stress severely restricts grape (Vitis vinifera L.) production. Serine/arginine-rich (SR) proteins, as a class of RNA-binding proteins, play important roles in plant growth, development and stress responses. However, the function and regulatory mechanism of VvSR34a in grape salt tolerance remain unclear. In this study, grape callus and cutting seedlings were used as materials to explore the role and molecular mechanism of VvSR34a in grape salt stress response. The results showed that, under 100 mM NaCl treatment, the relative level of VvSR34a in grape callus exhibited a ‘first increase and then decrease’ pattern, reaching a peak at 2 h, and the gene was localized in the nucleus. Transgenic experiments confirmed that the overexpression of VvSR34a significantly enhanced salt tolerance in grape callus and cuttings, as evidenced by better growth status, higher chlorophyll content and root activity, as well as lower electrolyte leakage and malondialdehyde (MDA) content under salt stress. In contrast, the silencing of VvSR34a significantly increased salt sensitivity in grapes. Y2H and LCI assays verified that VvSR34a physically interacts with VvCOP9. VvCOP9 may play a negative regulatory role in the salt stress response of the grapevine, and through the loss of the high salt-tolerant phenotype in the VvSR34a/VvCOP9-RNAi lines, it demonstrated that VvCOP9 is genetically upstream of VvSR34a. Furthermore, the ubiquitination and degradation assay demonstrated that VvCOP9 can significantly promote the degradation of VvSR34a. RNA-seq analysis showed that a total of 2834 differentially expressed genes and 202 alternative splicing events were detected in VvSR34a overexpression lines. These differentially expressed genes were significantly enriched in ATPase activity, redox and hormone signaling pathways. This study demonstrates that VvSR34a positively regulates salt tolerance in grapes, providing an important theoretical basis for molecular breeding of salt-tolerant grapevines. Full article