NaCl Salinity Research Articles

Effect of Organic Fertilizer on the Growth and Physiological Parameters of a Traditional Medicinal Plant under Salinity Stress Conditions

Foeniculum vulgare (fennel) is a medicinal and aromatic plant species from Apiaceae (Umbelliferae) and has been extensively used to treat digestive and pulmonary diseases. This plant is relatively sensitive to salinity. To investigate the effect of salinity stress at levels of 0, 40, and 80 mM NaCl in combination with 0 and 5% v/v vermicompost mixed with soil on the growth as well as the physiological and biochemical traits of two fennel landraces planted in Urmia and Shiraz areas, a factorial experiment was conducted as a randomized complete block design in three replications under greenhouse conditions. The plants were sampled in the flowering stage eleven weeks after cultivation. As the results showed, vermicompost treatment together with salinity stress could enhance the growth traits of the plants, such as the length and dry weight of shoots; leaf area and dry weight of roots; photosynthetic pigments, i.e., chlorophylls and carotenoids; membrane stability index; relative water content, soluble sugar, soluble protein, proline, total phenol, and anthocyanin in the shoots; mineral elements, i.e., phosphate, nitrate, zinc, molybdenum, magnesium, and iron in the shoots; and potassium and calcium in the shoots and roots. The interaction of vermicompost and salinity also decreased the aldehydes, total flavonoids, activity of catalase enzyme and shoot starch, soluble sugar and root proline, and sodium content of both shoots and roots. In a comparison of the two studied fennel landraces, the Shiraz landrace emerged to be less affected by salinity stress. In saline conditions, vermicompost caused a change in the physiological and biochemical parameters of both fennel landraces and improved their growth. The improvement in the growth conditions in the Urmia landrace was more obvious due to the use of vermicompost. Using vermicompost plus 40 mM NaCl salinity, the dry weight of the shoot and leaf surface of the Urmia landrace increased by about 3 and 2.5 times, respectively, and under 80 mM NaCl, the dry weight of the shoot and leaf surface increased by 2.7 and 1.2 times compared to the control. According to the experiments, it seems that vermicompost can limit the harmful effects of salinity on fennel plants by affecting photosynthetic pigments, osmolytes, phenolic compounds, antioxidants, the stability of membranes, and the availability of water and essential minerals.

Physiological and transcriptome analysis reveals that prohexadione-calcium promotes rice seedling's development under salt stress by regulating antioxidant processes and photosynthesis.

Prohexadione-calcium (Pro-Ca) has been proved to play an important role in releasing abiotic stress in plants. However, there is still a lack of research on the mechanism of Pro-Ca alleviating salt stress in rice. To explore the protective effects of Pro-Ca on rice seedlings under salt stress, we investigated the effect of exogenous Pro-Ca on rice seedling under salt stress by conducting the following three treatment experiments: CK (control), S (50 mmol·L-1 NaCl saline solution) and S + Pro-Ca (50 mmol·L-1 NaCl saline solution + 100 mg·L-1 Pro-Ca). The results indicated that Pro-Ca modulated the expression of antioxidant enzyme-related genes (such as SOD2, PXMP2, MPV17, E1.11.1.7). Spraying Pro-Ca under salt stress significantly increased in ascorbate peroxidase, superoxide dismutase, and peroxidase activity by 84.2%, 75.2%, and 3.5% as compared to the salt treatment, as demonstrated by an example of a 24-hour treatment. Malondialdehyde level in Pro-Ca was also dramatically decreased by 5.8%. Moreover, spraying Pro-Ca under salt stress regulated the expression of photosynthesis genes (such as PsbS, PsbD) and chlorophyll metabolism genes (heml, PPD). Compared to salt stress treatment, spraying Pro-Ca under salt stress significantly increased in net photosynthetic rate by 167.2%. In addition, when rice shoots were sprayed with Pro-Ca under salt stress, the Na+ concentration was considerably reduced by 17.1% compared to salt treatment. In conclusion, Pro-Ca regulates antioxidant mechanisms and photosynthesis to aid in the growth of rice seedlings under salt stress.

Experimental investigation of surfactant adsorption during EOR and soil pollution control processes: Influence of surfactant concentration, water salinity, and clay type

Surfactant injection is a well-established method of chemical EOR processes. Surfactant adsorption into clay layers can prevent their proper performance and thus reduce the oil recovery factor. On the other hand, this adsorption property of clay materials can be used to prevent surface and underground water pollution and reduce soil pollution. In this experimental study, the effect of surfactant concentration, electrolyte type (NaCl and MgCl2), and the solution salinity on fluid adsorption into the interlayer space of different clay types (bentonite and kaolinite) was investigated. XRF analysis was conducted on two relevant clay samples, and immersion and Washburn tests were performed on the desired samples with the Sigma 700 setup. Then, according to the clay type, the most optimal conditions were introduced for the surfactant solution used in the two areas of EOR and environmental processes related to reducing soil pollution. In the EOR processes, the optimal condition for the lowest adsorption amount is C (with 1 CMC concentration and salinity of 100,000 ppm for NaCl salt). This fluid works better in kaolinite formations. In the environmental field related to the reduction of soil pollution, if the pollutants we are looking for are R and S (with alkyl benzene sulfonic acid as the dominant agent), bentonite has a better performance than kaolinite in terms of adsorption and subsequently pollution control. If the polluting fluid contains MgCl2 ions in the exact salinity values, the adsorption amount and soil pollution control will be higher for both adsorbent clays than if our fluid has NaCl salinity. The study's findings have a wide range of applications in surfactant flooding designs, surfactant adsorption optimization, and can be generalized to other detergent types.

Effects of halotolerant rhizobacteria on rice seedlings under salinity stress

Avirulent halotolerant plant growth-promoting rhizobacteria (HPGPR) located on the roots' periphery can reduce abiotic stressors (such as salinity and drought), enhance plant productivity. Salinity poses a significant challenge for growing agricultural products, like rice, in the coastal regions. It is crucial to enhance production because of limited arable land and the high growth rate of the population. This study targeted to identify HPGPR from legume root nodules and assessed their effects on rice plants experiencing salt stress in coastal regions of Bangladesh. Based on the culture morphology, biochemical, salt, pH, and temperature tolerance traits, sixteen bacteria were isolated from the root nodules of leguminous plants (Common bean, Yardlong bean, Dhaincha, and Shameplant). All the bacterial strains can tolerate 3 % salt concentration, and capable to survive at the highest 45 °C temperature and pH 11 (without isolate 1). Three preeminent bacteria, Agrobacterium tumefaciens (B1), Bacillus subtilis (B2), and Lysinibacillus fusiformis (B3) were specified through morpho-biochemical and molecular (16S rRNA gene sequence) exploration for inoculation. To assess the plant growth-promoting activities, germination tests are applied where bacterial inoculation increased germination in saline and non-saline conditions. Control group (C) showed 89.47 % and bacterial treated groups (C + B1, C + B2, and C + B3) 95 %, 90 %, and 75 % germination after 2 days of inoculation. In (1 % NaCl) saline condition control group revealed 40 % whereas three groups with bacteria showed 60 %, 40 %, and 70 % germination after 3 days, which increased 70 %, 90 %, 85 %, and 95 % respectively after 4 days of inoculation. The HPGPR significantly improved plant development metrics such as root length, shoot length, fresh and arid biomass yield, chlorophyll content, etc. Our results suggest that the salt-resistant bacteria (Halotolerant) have a great potential role in recuperating plant growth and would be cost-effective as a bio-inoculant in saline conditions to be used as a prospective bio-fertilizer for rice production. These findings indicate that the HPGPR has a substantially promising function in reviving plant development in an eco-friendly manner.

The Sorption Behaviors of Barium during Reinjection of Gas Field Produced Water into Sandstone Reservoir: An Experimental Water-Rock Interaction Study

Identifying the fate of contaminants (such as barium) during gas field produced water reinjection could be a feasible method to evaluate the environmental risks of the reinjection project and thus improve its sustainability. To assess the barium sorption behaviors during gas field produced water reinjected into sandstone reservoirs, a series of water–rock interactions experiments were conducted to systematically investigate the effects of brine/rock ratio (5:1~500:1), pH (3~10), temperature (20, 50 and 80 °C), brine salinity (NaCl solution, 0~100 g/L), competitive cations (Sr and Mg, 0.5 g/L), and organic compound (methanol, 0~5 g/L) on the sorption of barium in sandstone. The rock samples were collected from the Triassic formation of the Yanchang Group in the northern Ordos Basin, China. The results indicated that the sorption of barium in sandstone strongly depends on the brine/rock ratio. Under the same brine/rock ratio, the severity of the impact on the barium sorption from high to low was competitive cation, salinity, pH, temperature, and methanol concentration. The sorption process of barium onto the sandstone could be well fitted by a pseudo-second-order kinetics model. The presence of competitive cations would restrain the sorption of barium, while the existence of methanol hardly affects the barium sorption. The chloro-complexation reaction and the reduction of rock surface electrical potential are mainly responsible for the inhibition effects of NaCl salinity on barium sorption, and the corresponding relationship can be characterized by an exponential function. Barium sorption in sandstone decreases with increasing temperature, while it is positively correlated to the initial pH of the solution. The water-rock system is weakly alkaline with a value of 7.7–8.5 when the barium sorption reaches an equilibrium state, regardless of the initial pH of the reactive solution. The results are meaningful in understanding and predicting the fate of barium after the gas field produced water was reinjected into the underground.

Seasonal Influence on Oocyte Recovery Rate, Quality and in vitro Maturation in Cows

Background: Recent breakthroughs in vitro maturation, fertilization and culture technology have allowed for an increase in the number of offspring generated from genetically better females, but this progress is still hampered by critical factors affecting oocyte yield and quality. This study aims to evaluate the effect of the seasons on the rate of maturation and recovery of oocytes. Methods: The ovaries were brought from the slaughterhouse in Riyadh, Saudi Arabia, in a 0.9% NaCl saline solution and brought to the laboratory within 2-3 hours at a temperature of 25-35°C. Only the collected oocytes with two layers or more of cumulus cells (CCs) and uniform ooplasm were used. Five repetitions were made in each season of the year, followed by their ripening in the laboratory and a follow-up ripening after 24 hours. Observe the maturity rate after the stain and the expansion of cumulus cells and compare them with other seasons. Result: The mean maturation rates of MII and MI oocytes were not significantly different between all seasons. Additionally, there were no significant changes in the cumulus-oocyte complex before maturation in all seasons. However, after maturation, a highly significant difference (P less than 0.001) was found between the spring season before and after maturation (156.31±17.68 mm) and the rest of the seasons (summer; 169.89±19.96 mm; autumn; 176.66±20.14 mm; and winter; 188.84±24.50 mm). In order to improve in vitro maturation for following investigations, such as in vitro fertilization or cloning and in vitro embryo development, the ideal season should be chosen for collecting oocytes.

Physiological Responses of Two Olive Cultivars to Salt Stress.

The olive tree (Olea europaea L.) is the main fruit tree in most of the arid and semi-arid regions of Tunisia, which is where the problem of salinity is more pronounced. Salinity is one of the main factors that affects the productivity of olive trees, so the objective of this experiment was to study the effects of salinity on the photosynthesis, water relations, mineral status, and enzymatic activity of two cultivars of Olea europaea L., 'Chemlali' and 'Koroneiki'. The trial was conducted under controlled conditions in a greenhouse for a period of 49 days and included two treatments: T0 control and T100 (irrigation with 100 mM of NaCl solution). Under salinity stress, the photosynthesis, stomatal conductance, and leaves of both cultivars were negatively affected. 'Chemlali' showed greater tolerance to NaCl salinity, based on a progressive decrease in osmotic potential (Ψπ) followed by a progressive and synchronous decrease in gs, without a comparable decrease in photosynthesis. The water use efficiency (WUE) improved as a result. In addition, the K+/Na+ ratio in 'Chemlali' rose. This appears to be crucial for managing stress. Conversely, enzymatic activity showed an accumulation of glutathione peroxidase (GPX) in stressed plants. The catalase (CAT) and ascorbate peroxidase (APX) content decreased in both stressed varieties. It can be concluded that the cultivar 'Koroneiki' is more susceptible to salt stress than the cultivar 'Chemlali', because the accumulation of GPX and the decreases in CAT and APX were more pronounced in this cultivar.

Overexpression of type II rice metacaspase, OsMC4, increases endoplasmic reticulum stress tolerance in transgenic rice calli

The endoplasmic reticulum (ER) is an organelle responsible for regulating protein synthesis in plants. High salinity can lead to the accumulation of misfolded proteins, resulting in an ER stress response mechanism known as the unfolded protein response (UPR). Failure of the UPR to reverse the effect of protein misfolding will activate programmed cell death (PCD). Metacaspase genes are known regulate PCD in plants. This study aims to provide a comprehensive analysis of the expression patterns of type II rice metacaspase (OsMC) genes in response to ER and salinity stress in rice leaf. Among five type II metacaspases in the rice genome, OsMC4, OsMC5, and OsMC8 expressions were found to be upregulated during treatment with tunicamycin (ER stress) and sodium chloride, NaCl (salinity stress). A construct of taqRFP::OsMC4, controlled by the CaMV35S promoter, was generated and transformed into rice calli. The transgenic rice calli overexpressing taqRFP::OsMC4 demonstrated significant changes in the expression of the ER stress-marker genes, protein disulfide isomerase (OsPDI), and binding immunoglobulin protein (OsBiP). The results from this analysis provide preliminary evidence that at least one of the type II metacaspases, OsMC4, is be able to reduce ER and salinity stresses in rice. Further functional analysis of OsMC genes in ER and salinity stress tolerance could be carried out in transgenic rice overexpressing OsMCs in the future to improve stress tolerance. Simple summaryOryza sativa, commonly known as rice, is one of the most consumed crops in the world. In response to multiple biotic and abiotic factors, a series of endoplasmic reticulum (ER) stress response regulators are activated. There is evidence that high salinity triggers ER stress in plants. This study aims to determine the level of gene expression among type II metacaspases in rice in response to ER and salinity stress and to assess how they may be linked to PCD in rice calli. Three metacaspase genes, OsMC4, OsMC5, and OsMC8, have been observed to have significant expression post-treatment with tunicamycin in rice leaf. Overexpression of taqRFP::OsMC4 in rice calli significantly reduces the expression level of the stress markers, OsBiP and OsPDI, indicating that the stress level is relatively lower in the transgenic calli compared to the wild-type calli. Therefore, overexpression of taqRFP::OsMC4 in rice may increase rice tolerance towards ER and salinity stress. These expression analyses of the OsMCs family provide valuable information for further functional studies on the biological roles of OsMCs in ER and salinity stress responses.

Modafinil Improves Autism-like Behavior in Rats by Reducing Neuroinflammation.

To evaluate the ameliorating effect of Modafinil on neuroinflammation, behavioral, and histopathological alterations in rats induced by propionic acid (PPA). Thirty male Wistar rats were used in the study, divided into 3 groups of ten subjects. One group served as a control, the subjects in the other two were given 250mg/kg/day of PPA by intraperitoneal injection over the course of 5days to induce autism. The experimental design was as follows: Group 1: Normal control (orally-fed control, n = 10); Group 2 (PPA + saline, n = 10): PPA and 1ml/kg/day % 0.9 NaCl saline via oral gavage; Group 3 (PPA + Modafinil, n = 10) PPA and 30mg/kg/day Modafinil (Modiodal tablets 100mg, Cephalon) via oral gavage. All of the groups were investigated for behavioral, biochemical, and histological abnormality. Autism-like behaviors were reduced significantly in the rats treated with PPA. TNF-α, Nerve Growth Factor (NGF), IL-17, IL-2, and NF-KB levels as well as MDA levels and lactate were significantly higher in those treated with PPA compared to the control group. Using immunohistochemical methods, the number of neurons and GFAP immunoreactivity was significantly altered in PPA-treated rats compared to the control. Using Magnetic Resonance Spectroscopy (MRS), we found that lactate levels were significantly higher in the PPA-treated rats, while creatinine levels were significantly decreased. In the rats administered with Modafinil, behavior, neuroinflammation, and histopathological changes brought about by PPA were significantly reversed. Our results demonstrate the potential role of Modafinil in ameliorating PPA-induced neuroinflammation in rats.

Origin and hydrogeochemical formation processes of geothermal fluids from the Kibiro area, Western Uganda

The Kibiro geothermal field, located in the western branch of the East African Rift Valley System, has many geothermal surface manifestations. Several geochemical research has already been carried out in this area. However, the sources of dissolved ions in geothermal fluids have not been assessed so far. The hydrochemical and gas isotopic characteristics have been examined in this study to identify and determine the sources of the main dissolved components and the geochemical processes involved in the formation of the geothermal fluid. Methods applied in the analysis of the genesis and hydrogeochemical evolution of geothermal fluids include isotope tracers, major ion ratios, graphical methods (stability diagrams, durov diagrams, chloro-alkaline indices, piper diagrams, and HNC-plot), and hydrogeochemical simulations using PHREEQC software. The Kibiro hot springs are high salinity Na–Cl waters. Based on δ18O and δ2H values, the geothermal waters are found to be of meteoric origin. The assessments indicate that Na+ and Cl− are derived from halite dissolution. The dissolution of dolomite, calcite, gypsum, and anhydrite is responsible for the concentration of Ca2+, Mg2+, SO42−, and HCO3−. The main source of K+ is derived from the dissolution of silicate rocks (K-feldspar). The gas isotopes analysis indicates that 97.5% of He with isotope ratio of 0.217 Ra mainly originates from crustal sources and 2.47% is derived from the mantle. 51.39% of CO2 originates from marine limestone, 46.55% from sedimentary organic carbon and 2.06% from the mantle. This evidence further confirms that there are no direct inputs of volatiles from a magma chamber below the Kibiro geothermal field. The evolution of the fluids suggests that most of the common cations and anions found in the Kibiro hot spring waters originated from high-temperature water/rock interaction.

Growth and Metabolic Response of Glycine max to the Plant Growth-Promoting Enterobacter Delta PSK and Bradyrhizobium japonicum Under Salinity Stress

This study was designed to test the ability of some plant growth-promoting bacteria to adverse the effects of salinity on soybean growth. The effect of Bacillus MAP3 and Enterobacter Delta PSK, along with Bradyrhizobium japonicum was studied on soybean at two levels of NaCl salinization (50 and 100 mM). The physical growth parameters of bacterized soybean (21 days old), particularly plants co-inoculated with Bradyrhizobium japonicum + Enterobacter Delta PSK, were significantly enhanced compared to control plants. The shoot length, leaf area, root length, and chlorophyll a content increased by 49.58%, 78.58%, 20.19%, and 57.35%, respectively, indicating the promoting activity of this bacterial combination. After 19 days following the onset of salinity stress, the retarded growth parameters in controls improved significantly due to bacterial treatments, especially by Bradyrhizobium japonicum + Enterobacter DeltaPSK, which increased the values of all growth parameters significantly regardless of the salinity level. Additionally, electrolyte leakage, the amounts of malondialdehyde and hydrogen peroxide decreased considerably due to this combined bacterial treatment. Overall, the combination treatment of Enterobacter Delta PSK and the original symbiont B. japonicum enhanced soybean growth under salt stress, indicating the ability of Enterobacter Delta PSK to mitigate osmotic stress. The effect of this strain on soybean yield should be further evaluated to pave the way for its use as a biofertilizer along with B. japonicum, especially under salt stress.

Interaction of NaCl salinity and light intensity affect growth, physiological traits and essential oil constituents in Artemisia dracunculus L. (tarragon)

Soil salinity is one of the major limiting factors of medicinal plant performance and may affect their properties and chemical constituents. Although various reports have suggested the light quality-mediated modulation of growth and metabolism, little is known about physiological and phytochemicals aspects of light intensity on medicinal plants. In the present study, a factorial experiment as a randomized complete block design with three replicates was conducted to investigate the effects of salinity stress and light intensity on tarragon plants grown in pots at outdoor conditions. The experimental treatments consisted of NaCl salt stress at three levels (0, 60, and 120 mM) and different light intensities (full light, 75% of sunlight, and 50% of sunlight). According to the results, salinity led to a reduction in plant height, shoot dry weight, relative water content (RWC), and chlorophyll content compared to control conditions. While low light intensity improved the above mentioned characteristics. However, the interaction effect of salinity (60 mM) and low light intensity significantly increased anthocyanin and chlorophyll contents, and dry weight. Overall, tarragon yield can be improved at 75% of light intensity and moderate salinity by increasing the synthesis of photosynthetic pigments and phenolic compounds as protective substances. Essential oils examined here were particularly rich in methyl chavicol (68.39–79.02%), camphene (0.26–6.28%), β-pinene (0.24–5.21%), and trans-β-o-cymene (1.49–4.53%).

Quality analysis of genomic DNA and authentication of fisheries products based on distinct methods of DNA extraction.

Molecular genetic techniques are an effective monitoring tool, but high-quality DNA samples are usually required. In this study, we compared three different protocols of DNA extraction: NaCl (saline); phenol-chloroform and commercial kit (Promega)-from three biological tissues of five individuals of Lutjanus purpureus under two methods of storage. The evaluated items included DNA concentration and purity, processing time and cost, as well as the obtaining of functional sequences. The highest average values of DNA concentration were obtained using the saline procedure and the commercial kit. Pure DNA was only obtained using the saline protocol, evaluated by the ratio of 260/280. The saline and phenol-chloroform protocols were the least expensive methods. The commercial kit costs are counterbalanced by the short time required. The procedure based on phenol-chloroform presented the worst results regarding DNA yield and the time required to perform all steps. The saline and commercial kit protocols showed similar results concerning the amount and quality of extracted DNA. Therefore, the final choice should be based on the available financial resources and the available time for carrying out each procedure of DNA extraction.

Microphysics of liquid water in sub-10 nm ultrafine aerosol particles

Abstract. Ultrafine aerosol particles with sizes smaller than 50 nm have been shown in recent studies to serve as a large source of cloud condensation nuclei that can promote additional cloud droplet formation under supersaturation conditions. Knowledge of the microphysics of liquid water in these droplets remains limited, particularly in the sub-10 nm particle size range, due to experimental and theoretical challenges associated with the complexity of aerosol components and the small length scales of interest (e.g., difficulty of precisely sampling the liquid–air interface, questionable validity of mean-field theoretical representations). Here, we carried out molecular dynamics (MD) simulations of aerosol particles with diameters between 1 and 10 nm and characterized atomistic-level structure and water dynamics in well-mixed and phase-separated systems with different particle sizes, NaCl salinities, and pimelic acid (PML) organic surface loadings as a function of distance from the time-averaged Gibbs dividing interface or instantaneous water–air interface. We define a sphericity factor (ϕ) that can shed light on the phase-mixing state of nanodroplets, and we reveal an unexpected dependence of mixing state on droplet size. Our results also evidence an ion concentration enhancement in ultrafine aerosols, which should modulate salt nucleation kinetics in sub-10 nm droplets, and provide detailed characterization of the influence of droplet size on surface tension and on water self-diffusivity near the interface. Analysis of water evaporation free energy and water activity demonstrates the validity of the Kelvin equation and Köhler theory at droplet sizes larger than 4 nm under moderate salinities and organic loadings and the need for further extension to account for ion concentration enhancement in sub-10 nm aerosols, droplet-size-dependent phase separation effects, and a sharp decrease in the cohesiveness of liquid water in sub-4 nm droplets. Finally, we show that an idealized fractional surface coating factor (fs) can be used to categorize and reconcile water accommodation coefficients (α*) observed in MD simulations and experimental results in the presence of organic coatings, and we resolve the droplet size dependence of α*.

RELACIÓN BRADYRIZOBIUM-CAUPÍ EN CONDICIONES DE SALINIDAD: SU INFLUENCIA EN LA TOLERANCIA AL ESTRÉS SALINO

<p><strong>Background:</strong> The introduction of species with tolerance to salinity is one of the strategies to reduce the harmful effect of salts in the eastern region of Cuba. The species <em>Vigna unguiculata</em> L., shows rusticity and capability of adaptation, however, it is necessary to search for cultivars with greater tolerance and symbiotic nitrogen fixation possibilities to increase yields. <strong>Objective: </strong>To determine the behavior of the <em>bradyrizobium</em>-cowpea bean relationship under salinity conditions, based on variables related to symbiotic nitrogen fixation, growth and development. <strong>Methodology:</strong> An experiment was carried out under controlled glass house conditions at the CSIC, Madrid, Spain. Two cultivars were used; IITA-Precoz and IT 86 D-715, which were inoculated with Strain VIBA-1 of <em>Bradyrhizobum liaoningense.</em> Treatments were Hoagland nutrient solution (control) and nutrient solution with 150 mM NaCl (saline). A completely randomized design with eight replications was used. At 40 days after germination, variables related to symbiotic nitrogen fixation, growth and development, protein concentration of the cytosolic soluble fraction of leaves and nodules were evaluated.<strong> Results: </strong>Although salinity negatively affected both cultivars, the damage did not manifest with the same intensity. IT 86 D-715 was less affected by showing less damage on the variables number of nodules, ARA, protein concentration in nodules and leaves, accumulation of leaf and root biomass, so its tolerance was greater. The IITA-Precoz cultivar was more susceptible, all the variables were notably affected under stress conditions, therefore, its tolerance level is lower. <strong>Implications:</strong> The cultivar IT 86 D-715 can be used in salinized soils due to its high tolerance, which is evidenced in variables of growth development and atmospheric nitrogen fixation. <strong>Conclusions: </strong>The cultivar IT 86 D-715 presents a greater capacity for symbiotic nitrogen fixation under salinity conditions and the tolerance index in all the growth and development variables evaluated was higher than IITA-Precoz, for which it presents a high susceptibility level.</p>

New geochemical data for defining origin and distribution of mercury in groundwater of a coastal area in southern Tuscany (Italy)

A geochemical study was conducted in a coastal plain in the Orbetello Lagoon area in southern Tuscany (Italy), acquiring new data on groundwater, lagoon water, and stream sediment for insights into the origin, distribution, and behaviour of mercury in a Hg-enriched carbonate aquifer. The main hydrochemical features of the groundwater are ruled by the mixing of Ca–SO4 and Ca–Cl continental fresh waters of the carbonate aquifer and Na–Cl saline waters of the Tyrrhenian Sea and Lagoon of Orbetello. Groundwater had highly variable Hg concentrations (< 0.1–11 μg/L) that were not correlated with the percentage of saline water, depth in the aquifer, or distance from the lagoon. This excluded the possibility that saline water could be the direct source of Hg in groundwater and responsible for release of the element through interaction with the carbonate lithologies of the aquifer. The origin of Hg in groundwater could be ascribed to the Quaternary continental sediments overlying the carbonate aquifer because i) high Hg concentrations were found in the continental sediments of the coastal plain and in the contiguous lagoon sediments; ii) waters from the upper part of aquifer had the highest Hg concentrations; iii) Hg levels in groundwater increased with increasing thickness of the continental deposits. The high Hg content in the continental and lagoon sediments is geogenic due to regional and local Hg anomalies and to sedimentary and pedogenetic processes. It can be assumed that i) water circulating in these sediments dissolves the solid Hg-bearing constituents and mobilises this element mainly as chloride complexes; ii) Hg-enriched water moves from the upper part of the carbonate aquifer due to the cone of depression generated by intense pumping of groundwater by fish farms in the study area.

Appraisal of Salt Sensitivity among Elite Genotypes of Chickpea (Cicer arietinum L.) At Seedling Stage

Background: The cool-season grain legume chickpea (Cicer arietinum L.) crop is sensitive to salt stress. Especially, NaCl salt inhibits both the rate and extent of seed germination and plant establishment. Methods: The 20 Desi chickpea genotypes were investigated under different levels of NaCl salt stress (0, 4, 6, 8, and 10 dS/m) at the seedling stage with three replications during Rabi 2020-21. Observations were recorded at 15 and 30 DAS (Days after sowing) for seedling growth, vigor, and physiological performance. Result: The seedling length (cm), fresh weight (g), and relative water content (RWC%) exhibited decreasing trends and reversibly increasing trends by the relative stress injury (RSI%) with increasing NaCl salinity levels. The values of the length of coleoptile and radicle (cm) at control to 10 dS/m ranged from 15.9-8.6 cm and 29.6-18.3 cm, respectively at 15 DAS and from 20.5-12.8 cm and 30.3-18.3 cm, respectively at 30 DAS. The chickpea genotypes identified as the source of salinity tolerance were HC5, HC3, HC1, H12-22, H14-14, and H03-56 as they maintained higher growth, water status, and fewer membrane injuries at the seedling stage, recognized as screening tools under salt stress which could be used to enhance/develop a new salt-tolerant variety in chickpea breeding programme.

Effects of prenatal testosterone exposure on the development of autism-like behaviours in offspring of Wistar rats.

A neurodevelopmental disease, autism spectrum disorder (ASD) occurs in males three times more commonly than girls. Higher prenatal testosterone exposure may result in autistic-like behaviour in boys, according to earlier research. It is unclear how fetal testosterone affects the development of autism. In this study, we tested the hypothesis that prenatal testosterone exposure in an animal model may result in autistic behaviours by modifying serotonin, dopamine, IGF-1 and oxytocin levels. Group 1 (control, n = 6) and Group 2 (testosterone undecanoate, n = 6) of female rats were randomly assigned. For 2-3days during the oestrus cycle, female rats were housed with a reproductive male (three females/one male). On the 10th day of gestation, rats in Group 1 received 1ml/kg% 0.9 NaCl saline, whereas rats in Group 2 received 250 mg/kg testosterone undecanoate. Until weaning on postnatal day 21 (P21), the mothers were permitted to care for their pups. On P21, 40 littermates-10 male and female for control and 10 male and female from mothers that exposed to testosterone-were arbitrarily split up and housed. On P50, these mature rats were tested for their behaviour. The rats were then sacrificed. The brain tissue was subjected to histological examinations as well as biochemical tests for homovanillic acid (HVA), 5-Hydroxyindoleacetic acid (5-HIAA), oxytocin and insulin-like growth factor-1 (IGF-1). The groups differed significantly in the behavioural examinations (three-chamber social test, passive avoidance learning analysis, open field test), with the testosterone-exposed groups exhibiting autistic symptoms to a higher extent. When compared with the control groups, testosterone exposure caused significant histological changes in the hippocampus CA1 and CA3 areas, including gliosis and cell death of neurons. In the testosterone-exposed groups, HVA, 5-HIAA and IGF-1 tissue expressions in the brain elevated, whereas oxytocin levels reduced. These findings point to a potential connection between neurodevelopmental disorders like ASD and exposure to testosterone during gestation. Overall, we revealed that prenatal testosterone exposure led to autistic traits by elevating serotonin, dopamine and IGF-1 levels while lowering oxytocin levels.

Corrosion resistance of magnesium phosphate cement under long-term immersion in different solutions

Magnesium phosphate cement (MPC) is widely utilised in engineering. However, it may be subject to corrosion in the Western Chinese saline soil environment. This study analysed the factors of magnesium phosphorus ratio, borax content, water binder ratio and fly ash content. Mix proportions of MPC were devised through orthogonal testing. The corrosion performance of MPC specimens in water, 5% Na2SO4 solution, 5% NaCl solution and saline soil solution were analysed in terms of mass loss and the strength anti-corrosion coefficient. The corrosion mechanisms of MPC in different solutions were analysed by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Thermogravimetric and differential scanning calorimetry (TG-DSC) and Scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS). There were no obvious changes in MPC appearance or morphology after soaking in different solutions for 180 days. The mass loss was < 5% and the strength loss was < 25%, indicating that MPC has good resistance to saline soil and other saline solutions. The strength anti-corrosion coefficients of MPC soaked in various solutions for 180 days were > 0.75, and the influences on strength can be ranked as follows: 5% Na2SO4 solution > saline soil solution > water > 5% NaCl solution. On the basis of TG-DSC, FTIR and XRD analyses, when MPC was soaked in different solutions for 180 d, the contents of the hydration product MgKPO4·6H2O (MKP) were ranked as water > 5% NaCl solution > saline soil solution > 5% Na2SO4 solution. SEM-EDS analysis shows that MKP was corroded to varying degrees after the MPC was soaked in different solutions, with the 5% Na2SO4 solution causing the greatest corrosion.

Dominance of Bacillus species in the wheat (Triticum aestivum L.) rhizosphere and their plant growth promoting potential under salt stress conditions.

Wheat (Triticum aestivum L.) is a major source of calorific intake in its various forms and is considered one of the most important staple foods. Improved wheat productivity can contribute substantially to addressing food security in the coming decades. Soil salinity is the most serious limiting factor in crop production and fertilizer use efficiency. In this study, 11 bacteria were isolated from wheat rhizosphere and examined for salt tolerance ability. WGT1, WGT2, WGT3, WGT6, WGT8, and WGT11 were able to tolerate NaCl salinity up to 4%. Bacterial isolates were characterized in vitro for plant growth-promoting properties including indole-3-acetic acid (IAA) production, phosphate solubilization, nitrogen fixation, zinc solubilization, biofilm formation, and cellulase-pectinase production. Six isolates, WGT1, WGT3, WGT4, WGT6, WGT8, and WGT9 showed IAA production ability ranging from 0.7-6 µg m/L. WGT8 displayed the highest IAA production. Five isolates, WGT1, WGT2, WGT5, WGT10, and WGT11, demonstrated phosphate solubilization ranging from 1.4-12.3 µg m/L. WGT2 showed the highest phosphate solubilization. Nitrogen fixation was shown by only two isolates, WGT1 and WGT8. Zinc solubilization was shown by WGT1 and WGT11 on minimal media. All isolates showed biofilm formation ability, where WGT4 exhibited maximum potential. Cellulase production ability was noticed in WGT1, WGT2, WGT4, and WGT5, while pectinase production was observed in WGT2 and WGT3. Phylogenetic identification of potential bacteria isolates confirmed their close relationship with various species of the genus Bacillus. WGT1, WGT2, and WGT3 showed the highest similarity with B. cereus, WGT6 with B. tianshenii, WGT8 with B. subtilis, and WGT11 with B. thuringiensis. Biofertilizer characteristics of salt-tolerant potential rhizospheric bacteria were evaluated by inoculating wheat plants under controlled conditions and field experiments. B. cereus WGT1 and B. thuringiensis WGT11 displayed the maximum potential to increase plant growth parameters and enhance grain yield by 37% and 31%, respectively. Potential bacteria of this study can tolerate salt stress, have the ability to produce plant growth promoting substances under salt stress and contribute significantly to enhance wheat grain yield. These bacterial isolates have the potential to be used as biofertilizers for improved wheat production under salinity conditions and contribute to the sustainable agriculture.