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Salt stress is a significant environmental factor affecting plant growth and development, with NaCl stress being one of the most common types of salt stress. The halophyte, Tamarix ramosissima Ledeb (T. ramosissima), is frequently utilized for the afforestation of saline-alkali soils. Indeed, there has been limited research and reports by experts and scholars on the regulatory mechanisms of basic leucine zipper (bZIP) genes in T. ramosissima when treated with exogenous potassium (K+) to alleviate the effects of NaCl stress. This study focused on the bZIP genes in T. ramosissima roots under NaCl stress with additional KCl applied. We identified key candidate genes and metabolic pathways related to bZIP and validated them through quantitative real-time PCR (qRT-PCR). The results revealed that under NaCl stress with additional KCl applied treatments at 0 h, 48 h, and 168 h, based on Pfam protein domain prediction and physicochemical property analysis, we identified 20 related bZIP genes. Notably, four bZIP genes (bZIP_2, bZIP_6, bZIP_16, and bZIP_18) were labeled with the plant hormone signal transduction pathway, showing a predominant up-regulation in expression levels. The results suggest that these genes may mediate multiple physiological pathways under NaCl stress with additional KCl applied at 48 h and 168 h, enhancing signal transduction, reducing the accumulation of ROS, and decreasing oxidative damage, thereby enhancing the tolerance of T. ramosissima to NaCl stress. This study provides gene resources and a theoretical basis for further breeding of salt-tolerant Tamarix species and the involvement of bZIP transcription factors in mitigating NaCl toxicity. [ABSTRACT FROM AUTHOR]

Introduction: Salinization affects more than 25% of the world's arable land, and Tamarix ramosissima Ledeb (T. ramosissima), the representative of Tamarix plants, is widely grown in salinized soil. In contrast, less is known about the mechanism of potassium's antioxidative enzyme activity in preventing NaCl stress damage to plants. Method: This study examined changes in root growth for T. ramosissima at 0h, 48h, and 168h, performed antioxidant enzyme activity assays, transcriptome sequencing, and non-targeted metabolite analysis to understand changes in their roots as well as changes in the activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT). Quantitative real-time PCR (qRT-PCR) was used to identify differentially expressed genes (DEGs) and differential metabolites associated with antioxidant enzyme activities. Result: As the time increased, the results showed that compared with the 200 Mm NaCl group, the root growth of the 200 mM NaCl + 10 mM KCl group increased, the activities of SOD, POD and CAT increased the most, but the contents of hydrogen peroxide (H2O2) and Malondialdehyde (MDA) increased less. Meanwhile, 58 DEGs related to SOD, POD and CAT activities were changed during the application of exogenous K+ for 48h and 168h in T. ramosissima. Based on association analysis of transcriptomic and metabolomic data, we found coniferyl alcohol, which can act as a substrate to label catalytic POD. It is worth noting that Unigene0013825 and Unigene0014843, as POD-related genes, have positively regulated the downstream of coniferyl alcohol, and they have a significant correlation with coniferyl alcohol. Discussion: In summary, 48h and 168h of exogenous K+ applied to the roots of T. ramosissima under NaCl stress can resist NaCl stress by scavenging the reactive oxygen species (ROS) generated by high salt stress by enhancing the mechanism of antioxidant enzyme activity, relieving NaCl toxicity and maintaining growth. This study provides genetic resources and a scientific theoretical basis for further breeding of salt-tolerant Tamarix plants and the molecular mechanism of K+ alleviating NaCl toxicity. [ABSTRACT FROM AUTHOR]

There is a serious problem with soil salinization that affects the growth and development of plants. Tamarix ramosissima Ledeb (T. ramosissima), as a halophyte, is widely used for afforestation in salinized soils. At present, there are few reports on the antioxidant mechanism of T. ramosissima under NaCl stress. In this study, we learned about the superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) activities, and hydrogen peroxide (H2O2) and malondialdehyde (MDA) content changes in T. ramosissima. We also mined the relevant metabolic pathways in the antioxidant mechanism, candidate key genes, and their related differential metabolites and verified them using quantitative real-time PCR (qRT-PCR). The results show that the SOD, POD, and CAT activities, and the H2O2 and MDA content reached the highest values in the roots of T. ramosissima. Simultaneously, 92 differentially expressed genes (DEGs) related to antioxidant enzyme activities changed during 48 and 168 h of NaCl stress, and these DEGs were mainly upregulated in 168 h. Based on the association analysis of transcriptomic and metabolomic data, we found Unigene0089358 and Unigene0007782 as genes related to key enzymes in the flavonoid biosynthesis pathway. They were located in the upstream positive regulation at 48 and 168 h under NaCl stress, and their respective related metabolites (phloretin and pinocembrin) were involved in resistance to NaCl stress, and they were significantly correlated with their respective metabolites. In conclusion, at 48 and 168 h under NaCl stress, the roots of T. ramosissima resist NaCl stress by enhancing enzymatic and nonenzymatic antioxidant mechanisms, scavenging ROS generated by high-salt stress, alleviating NaCl toxicity, and maintaining the growth of T. ramosissima. This study provides genetic resources and a scientific theoretical basis for further breeding of salt-tolerant Tamarix plants and the molecular mechanism of antioxidants to alleviate NaCl toxicity. [ABSTRACT FROM AUTHOR]

There is a serious problem with soil salinization that affects the growth and development of plants. Tamarix ramosissima Ledeb (T. ramosissima), as a halophyte, is widely used for afforestation in salinized soils. At present, there are few reports on the antioxidant mechanism of T. ramosissima under NaCl stress. In this study, we learned about the superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) activities, and hydrogen peroxide (H2O2) and malondialdehyde (MDA) content changes in T. ramosissima. We also mined the relevant metabolic pathways in the antioxidant mechanism, candidate key genes, and their related differential metabolites and verified them using quantitative real-time PCR (qRT-PCR). The results show that the SOD, POD, and CAT activities, and the H2O2 and MDA content reached the highest values in the roots of T. ramosissima. Simultaneously, 92 differentially expressed genes (DEGs) related to antioxidant enzyme activities changed during 48 and 168 h of NaCl stress, and these DEGs were mainly upregulated in 168 h. Based on the association analysis of transcriptomic and metabolomic data, we found Unigene0089358 and Unigene0007782 as genes related to key enzymes in the flavonoid biosynthesis pathway. They were located in the upstream positive regulation at 48 and 168 h under NaCl stress, and their respective related metabolites (phloretin and pinocembrin) were involved in resistance to NaCl stress, and they were significantly correlated with their respective metabolites. In conclusion, at 48 and 168 h under NaCl stress, the roots of T. ramosissima resist NaCl stress by enhancing enzymatic and nonenzymatic antioxidant mechanisms, scavenging ROS generated by high-salt stress, alleviating NaCl toxicity, and maintaining the growth of T. ramosissima. This study provides genetic resources and a scientific theoretical basis for further breeding of salt-tolerant Tamarix plants and the molecular mechanism of antioxidants to alleviate NaCl toxicity.

Soil salinization limit crop yield and deteriorate product quality in arid and semi-arid agroecological regions. Under such conditions regulation of mineral nutrients may help to sustain crop productivity. Therefore, a pot experiment was carried out to identify optimal sulfur level and source for enhancing salt adaptability of sunflower (Helianthus annuus L.). A uniform salinity level of 100 mM NaCl was developed in each pot and then six S treatments viz. S0, control; S1, 20 mg sulfur kg-1 soil; S2, 40 mg sulfur kg-1 soil; S3, 60 mg sulfur kg-1 soil; S4, 80 mg sulfur kg-1 soil and S5, 100 mg sulfur kg-1 soil were applied by using elemental S and K2SO4 as sulfur source. Supplementation of sulfur caused reduction in tissue Na+ accumulation and electrolyte leakage while increase in tissue K+ and Ca2+ with a subsequent increase in relative water content and photosynthetic rate of sunflower. Increasing sulfur levels in the form of K2SO4 depicted linear increase in plant growth and yield attributes up to 80 mg sulfur kg-1 soil beyond which there was decline in these growth characteristics suggesting that sulfur as K2SO4 at 80 mg sulfur kg-1 soil might be optimum in mitigating NaCl toxicity in sunflower.

Sodium chloride poisoning has been suspected in Iraqi buffalo (Bubalus bubalis) of Basrah governorate, A study was conducted on 523 animals. All animals drank natural water from the Shatt al-Arab sources. Seventy-six animals show different clinical manifestations, and twelve clinically healthy animals were used as controls. Diseased buffalo exhibited different clinical manifestations. A significant increase in PCV with alterations in indices of clotting factors was also explored. Serum analysis demonstrated increase in serum sodium and chloride concentrations in diseased buffalo. However, water analysis revealed elevation of electrical conductivity, sodium, chloride and total dissolved solids in the drinking water of diseased buffalo. The macroscopic appearance of the carcasses showed congestion and slight edema of the brain tissues, Moreover, the histopathological examinations revealed, spongiform-like encephalopathy with severe congested blood vessels and neuro-vascular thrombus was detected. [ABSTRACT FROM AUTHOR]

Soil salinization limit crop yield and deteriorate product quality in arid and semi-arid agroecological regions. Under such conditions regulation of mineral nutrients may help to sustain crop productivity. Therefore, a pot experiment was carried out to identify optimal sulfur level and source for enhancing salt adaptability of sunflower (Helianthus annuus L.). A uniform salinity level of 100 mM NaCl was developed in each pot and then six S treatments viz. S0, control; S1, 20 mg sulfur kg-1 soil; S2, 40 mg sulfur kg-1 soil; S3, 60 mg sulfur kg-1 soil; S4, 80 mg sulfur kg-1 soil and S5, 100 mg sulfur kg-1 soil were applied by using elemental S and K2SO4 as sulfur source. Supplementation of sulfur caused reduction in tissue Na+ accumulation and electrolyte leakage while increase in tissue K+ and Ca2+ with a subsequent increase in relative water content and photosynthetic rate of sunflower. Increasing sulfur levels in the form of K2SO4 depicted linear increase in plant growth and yield attributes up to 80 mg sulfur kg-1 soil beyond which there was decline in these growth characteristics suggesting that sulfur as K2SO4 at 80 mg sulfur kg-1 soil might be optimum in mitigating NaCl toxicity in sunflower. [ABSTRACT FROM AUTHOR]

Soil salinization limit crop yield and deteriorate product quality in arid and semi-arid agroecological regions. Under such conditions regulation of mineral nutrients may help to sustain crop productivity. Therefore, a pot experiment was carried out to identify optimal sulfur level and source for enhancing salt adaptability of sunflower (Helianthus annuus L.). A uniform salinity level of 100 mM NaCl was developed in each pot and then six S treatments viz. S0, control; S1, 20 mg sulfur kg-1 soil; S2, 40 mg sulfur kg-1 soil; S3, 60 mg sulfur kg-1 soil; S4, 80 mg sulfur kg-1 soil and S5, 100 mg sulfur kg-1 soil were applied by using elemental S and K2SO4 as sulfur source. Supplementation of sulfur caused reduction in tissue Na+ accumulation and electrolyte leakage while increase in tissue K+ and Ca2+ with a subsequent increase in relative water content and photosynthetic rate of sunflower. Increasing sulfur levels in the form of K2SO4 depicted linear increase in plant growth and yield attributes up to 80 mg sulfur kg-1 soil beyond which there was decline in these growth characteristics suggesting that sulfur as K2SO4 at 80 mg sulfur kg-1 soil might be optimum in mitigating NaCl toxicity in sunflower. [ABSTRACT FROM AUTHOR]

Soil salinity is among the main factors influencing seed germination in coastal dunes, acting as a major determinant of species establishment and growth. Tolerance to salinity during the germination process is crucial especially for species of the drift line, which are exposed to high levels. Cakile maritima is an annual species of coastal dunes which can suffer from the effects of salt-spray and seawater inundation. We investigated the effect of light, temperature and salinity on seed germination of C. maritima in three populations of the Mediterranean Basin (central Italy, Sardinia and Mallorca). Results showed higher germination percentage in the dark, although the species was only weekly photoinhibited. Germination increased at 25°C and decreased under NaCl conditions. Exposure to NaCl increased mortality, especially at high temperature, suggesting a toxic effect on seeds. However, the response to salinity differed between populations, seemingly depending on the degree of aridity of collection sites: seeds from Sardinia (the most arid collection site) were the most salt-tolerant, while seeds from Mallorca (with the highest values of precipitation, especially in spring), were the least salt-tolerant. These germination patterns suggest that although being under the same macroclimate conditions, beach populations can be subjected to local conditions, such as aridity, influencing population responses at fine scale. In the context of global climate change, the investigation of germination under varying environmental factors can provide important information for understanding population dynamics, predicting the response of species to climate change and setting restoration plans. [ABSTRACT FROM AUTHOR]

A pot culture study was performed to evaluate the differences between salt-stressed pea (Pisum sativum L.) plants of tolerant (Climax and Samarina Zard) and sensitive (Ambassidar and PF-400) genotypes, and to determine whether treatment with 24-epibrassinolide (EBL) could enhance the accumulation of osmolytes and antioxidant activity and thereby induce tolerance in salt-stressed plants. Three-week-old seedlings were subjected to +NaCl (5 dS m-1) and -NaCl conditions (0 dS m-1). After 4 days of salt stress, the plants were sprayed with Milli-Q water or EBL (0.125 mg L-1). The plants were sampled at 32 days after sowing and at the final maturity stage. Half-strength Hoagland solution was used as the nutrient medium. Both the tolerant and sensitive plants subjected to saline condition showed decreases in germination percentage, embryo axis length, plant fresh/dry biomass, leaf area, chlorophyll content, relative water content (RWC), photosynthesis, rubisco content, rubisco activity, stomatal conductance, number of stomata, stomatal size, number of epidermal cells, and yield attributes and increases in lipid peroxidation, total phenolics content, proline content, glycine betaine content, total amino acids content, total soluble sugars content, sucrose content, sucrose phosphate synthase activity, sucrose synthase activity, and activities of antioxidant enzymes (superoxide dismutase, peroxidase, catalase, ascorbate peroxidase, and guaiacol peroxidase). Salt stress had a less deleterious effect on Climax and Samarina Zard than on Ambassidar and PF-400. The foliar application of EBL mitigated the deleterious effects of NaCl by improving growth, productivity, and gas exchange attributes and by further enhancing the concentrations of the above osmolytes and antioxidants, particularly in the tolerant genotypes. The enhanced concentrations of osmolytes and antioxidants may have induced salt tolerance in the plants subjected to saline conditions, resulting in improved growth, gas exchange attributes, and yield. [ABSTRACT FROM AUTHOR]

Cynara cardunculus L., known as cynara for industrial application, is a versatile plant for Mediterranean regions. Irrigation with non-conventional salty water sources is a common practice in these water-scarce regions. However, the research performed on cynara salt-stress response is limited and solely tested under soilless conditions. Thereby, the aims of the current experiment were to ascertain the effect of saline irrigation on cynara growth and mineral nutrition in Mediterranean soils. The influence of soil was considered using two typical agricultural soils, mainly differing in their salinity status. Plants were grown under controlled conditions from November until July in pots filled with soil amended with sewage sludge compost. Three saline irrigation treatments were applied (0.7,2, and 3 dS·m-1) with increasing concentrations of NaCl (4,13, and 23 mM). Saline irrigation started in January and ended in June. Plants growth parameters (height, dry biomass, heads number, seed yield) declined with saline irrigation. Above-ground dry biomass of plants irrigated with 3 dS·m-1 was reduced approximately one-third regarding the control value, whereas seed yield was reduced in 57%. Despite growth reduction induced by salinity, no symptoms of nutritional deficiency were observed in leaves. Saline irrigation was the main driving factor regarding cynara mineral concentration, except for potassium (K) and manganese (Mn), which were related to soil type. Chlorine (Cl) and sodium (Na) concentration increased at the whole-plant level, whereas magnesium (Mg) showed the opposing trend. Similar trends were observed in the mineral content of cynara aboveground biomass. Interaction effects between soil type and saline irrigation were marginal. Cynara exhibited high K selectivity, which might be associated with a mechanism of salt tolerance, whereas Mg is suggested as a potential indicator of salt stress in cynara plants grown in calcareous Mediterranean soils. We concluded that cynara growth and mineral nutrition were mainly affected by saline irrigation, probably as a result of the accumulation of Na and Cl. [ABSTRACT FROM AUTHOR]

Salt tolerance in plants is a complex trait involving multiple mechanisms. Understanding these mechanisms and their regulation will assist in developing novel strategies to engineer salt-tolerant crops. In the current study, we investigated salt-tolerant mechanisms in soybean ( Glycine max) cultivar WF-7 in comparison to salt-sensitive Union. In vivo and in vitro salt assays demonstrated the salt tolerance of WF-7 at the seedling stage and during germination. After a 10-day 200 mM NaCl treatment, chlorophyll content in Union was reduced by 50 % compared to a 17 % reduction in WF-7. WF-7 was also less affected by abscisic acid (ABA) and NaCl during germination than Union. Upon ABA and NaCl treatment, the ABA-responsive genes SCOF1, ASN1, bZIP44, and AAPK1 are differentially expressed in WF-7 and Union seedlings. These results suggest that salt tolerance in WF-7 is in part regulated through an ABA-dependent pathway. In addition, following a 4-day 200 mM NaCl treatment, WF-7 produced more HO than Union indicating the involvement of reactive oxygen species (ROS) in regulating salt tolerance in WF-7. Yet another mechanism WF-7 employs is withholding toxic chloride (Cl) ions from aerial tissues. Following 200 mM NaCl treatment, Cl accumulation was mostly localized to the roots of WF-7. In contrast, most of the Cl in Union was transported into the stems and leaves. Taken together, our results demonstrated a role of ABA and ROS in regulating salt tolerance in WF-7, and the critical role of Cl in NaCl-induced mortality in soybean. Key message Withholding toxic Cl ions from leaves and, to a lesser extent, stems, confers salt tolerance to soybean WF-7. In addition, ABA and ROS may be involved in salt-stress signal transduction. [ABSTRACT FROM AUTHOR]

Daphnia magna is mainly recognized as a freshwater cladoceran, but there are some strains that grow in brackish waters. The tolerance to salinity of a freshwater strain was assessed at NaCl concentrations of 0, 2, 4, 6, and 7gL−1. The green microalga Ankistrodesmus falcatus was fed at optimal concentration (4×105 cellsmL−1). Reproduction and survival were recorded in two experimental series: in the first one, 20 female neonates were individually studied for each treatment. In the second, cohorts of 10 female neonates were distributed in each of five replicates per treatment. In both cases, experiments were conducted over a full life-cycle. The determined 48-h LC50 for NaCl was 5.48gL−1, but we recorded reproduction at up to 7gNaClL−1. The average clutch size, total progeny, number of clutches, and longevity were significantly reduced by the NaCl concentration (); total progeny ranged from 467 to 25 neonates as edge values for NaCl concentrations of 0–7gL−1. Inter-brood time was significantly higher for females grown at 7gNaClL−1 (3.9 days). The Life Table analysis demonstrates that average lifespan, life expectancy at birth, net reproductive rate and intrinsic rate of growth were also significantly reduced according to NaCl concentration. Based on the results for the two highest NaCl concentrations (6 and 7gL−1), we conclude that the used D. magna strain was acclimated to develop satisfactorily under concentrations of up to 6gNaClL−1; however, the established salinity conditions reduced significantly reproduction and survival in this strain. [Copyright &y& Elsevier]