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The moisture with salt ions adsorbed on the mineral soil surface is crucial to the cohesion process when the media is exposed to marine or coastal environments. However, the impact of salinity on the cohesion of soils is not well studied at the nanoscale. In this study, the salinity effect was investigated by studying the wettability and capillary force of NaCl solutions on quartz substrates via a molecular dynamics-based approach. Besides, a new visualization method was proposed to measure the contact angle of liquid droplets from the aspect of nanoscale. The results indicated that salt ions can weaken the wettability of the liquid on the quartz surface and inhibit the capillary force. Compared with water, the liquid with a 10% NaCl solution can achieve a capillary force reduction of around 70%, resulting in a detrimental effect on the cohesion of soils. Overall, this study enhanced the understanding of the nanoscale salinity effect on the cohesion process and provided insights into the modification of the mechanical properties of soils from the aspect of nanoscale. [ABSTRACT FROM AUTHOR]

Populations consuming saline drinking water are at greater risk of high blood pressure and potentially other adverse health outcomes. We modelled data and used available datasets to identify countries of higher vulnerability to future saltwater intrusion associated with climate change in 2050 under Representative Concentration Pathways (RCP)4.5 and RCP8.5. We developed three vulnerability criteria to capture geographies with: (1) any coastal areas with projected inland saltwater intrusion of ≥ 1 km inland, (2) > 50% of the population in coastal secondary administrative areas with reliance on groundwater for drinking water, and 3) high national average sodium urinary excretion (i.e., > 3 g/day). We identified 41 nations across all continents (except Antarctica) with ≥ 1 km of inland saltwater intrusion by 2050. Seven low- and middle-income countries of higher vulnerability were all concentrated in South/Southeast Asia. Based on these initial findings, future research should study geological nuances at the local level in higher-risk areas and co-produce with local communities contextually appropriate solutions to secure equitable access to clean drinking water.

Soil salinity is a major nutritional challenge with poor agriculture production characterized by high sodium (Na+) ions in the soil. Zinc oxide nanoparticles (ZnO NPs) and biochar have received attention as a sustainable strategy to reduce biotic and abiotic stress. However, there is a lack of information regarding the incorporation of ZnO NPs with biochar to ameliorate the salinity stress (0, 50,100 mM). Therefore, the current study aimed to investigate the potentials of ZnO NPs application (priming and foliar) alone and with a combination of biochar on the growth and nutrient availability of spinach plants under salinity stress. Results demonstrated that salinity stress at a higher rate (100 mM) showed maximum growth retardation by inducing oxidative stress, resulted in reduced photosynthetic rate and nutrient availability. ZnO NPs (priming and foliar) alone enhanced growth, chlorophyll contents and gas exchange parameters by improving the antioxidant enzymes activity of spinach under salinity stress. While, a significant and more pronounced effect was observed at combined treatments of ZnO NPs with biochar amendment. More importantly, ZnO NPs foliar application with biochar significantly reduced the Na+ contents in root 57.69%, and leaves 61.27% of spinach as compared to the respective control. Furthermore, higher nutrient contents were also found at the combined treatment of ZnO NPs foliar application with biochar. Overall, ZnO NPs combined application with biochar proved to be an efficient and sustainable strategy to alleviate salinity stress and improve crop nutritional quality under salinity stress. We inferred that ZnO NPs foliar application with a combination of biochar is more effectual in improving crop nutritional status and salinity mitigation than priming treatments with a combination of biochar.

Most of the available data on diffusion in natural clayey rocks consider tracer diffusion in the absence of a salinity gradient despite the fact that such gradients are frequently found in natural and engineered subsurface environments. To assess the role of such gradients on the diffusion properties of clayey materials, through-diffusion experiments were carried out in the presence and absence of a salinity gradient using salt-diffusion and radioisotope tracer techniques. The experiments were carried out with vermiculite samples that contained equal proportions of interparticle and interlayer porosities so as to assess also the role played by the two types of porosities on the diffusion of water and ions. Data were interpreted using both a classical Fickian diffusion model and with a reactive transport code, CrunchClay that can handle multi-porosity diffusion processes in the presence of charged surfaces. By combining experimental and simulated data, we demonstrated that (i) the flux of water diffusing through vermiculite interlayer porosity was minor compared to that diffusing through the interparticle porosity, and (ii) a model considering at least three types of porous volumes (interlayer, interparticle diffuse layer, and bulk interparticle) was necessary to reproduce consistently the variations of neutral and charged species diffusion as a function of salinity gradient conditions.

Mutants lacking functional HYD2 homoeologs showed improved seedling growth, but comparable or increased susceptibility to salt stress in tillering plants, suggesting a developmentally restricted role of HYD2 in salt response. Salinity stress threatens global food security by reducing the yield of staple crops such as wheat (Triticum ssp.). Understanding how wheat responds to salinity stress is crucial for developing climate resilient varieties. In this study, we examined the interplay between carotenoid metabolism and the response to salt (NaCl) stress, a specific form of salinity stress, in tetraploid wheat plants with mutations in carotenoid β-hydroxylase 1 (HYD1) and HYD2. Our investigation encompassed both the vulnerable seedling stage and the more developed tillering stage of wheat plant growth. Mutant combinations lacking functional HYD2 homoeologs, including hyd-A2 hyd-B2, hyd-A1 hyd-A2 hyd-B2, hyd-B1 hyd-A2 hyd-B2, and hyd-A1 hyd-B1 hyd-A2 hyd-B2, had longer first true leaves and slightly enhanced root growth during germination under salt stress compared to the segregate wild-type (control) plants. Interestingly, these mutant seedlings also showed decreased levels of neoxanthin and violaxanthin (xanthophylls derived from β-carotene) and an increase in β-carotene in roots. However, tillering hyd mutant and segregate wild-type plants generally did not differ in their height, tiller count, and biomass production under acute or prolonged salt stress, except for decreases in these parameters observed in the hyd-A1 hyd-B1 hyd-A2 hyd-B2 mutant that indicate its heightened susceptibility to salt stress. Taken together, these findings suggest a significant, yet developmentally restricted role of HYD2 homoeologs in salt-stress response in tetraploid wheat. They also show that hyd-A2 hyd-B2 mutant plants, previously demonstrated for possessing enriched nutritional (β-carotene) content, maintain an unimpaired ability to withstand salt stress.

Salinity is one of the substantial threats to plant productivity and could be escorted by other stresses such as heat and drought. It impairs critical biological processes, such as photosynthesis, energy, and water/nutrient acquisition, ultimately leading to cell death when stress intensity becomes uncured. Therefore, plants deploy several proper processes to overcome such hostile circumstances. Grapevine is one of the most important crops worldwide that is relatively salt-tolerant and preferentially cultivated in hot and semi-arid areas. One of the most applicable strategies for sustainable viticulture is using salt-tolerant rootstock such as Ruggeri (RUG). The rootstock showed efficient capacity of photosynthesis, ROS detoxification, and carbohydrate accumulation under salinity. The current study utilized the transcriptome profiling approach to identify the molecular events of RUG throughout a regime of salt stress followed by a recovery procedure. The data showed progressive changes in the transcriptome profiling throughout salinity, underpinning the involvement of a large number of genes in transcriptional reprogramming during stress. Our results established a considerable enrichment of the biological process GO-terms related to salinity adaptation, such as signaling, hormones, photosynthesis, carbohydrates, and ROS homeostasis. Among the battery of molecular/cellular responses launched upon salinity, ROS homeostasis plays the central role of salt adaptation.

Estuarine wetlands harbor considerable carbon stocks, but rising sea levels could affect their ability to sequester soil carbon as well as their potential to emit methane (CH4). While sulfate loading from seawater intrusion may reduce CH4 production due to the higher energy yield of microbial sulfate reduction, existing studies suggest other factors are likely at play. Our study of 11 wetland complexes spanning a natural salinity and productivity gradient across the San Francisco Bay and Delta found that while CH4 fluxes generally declined with salinity, they were highest in oligohaline wetlands (ca. 3-ppt salinity). Methanogens and methanogenesis genes were weakly correlated with CH4 fluxes but alone did not explain the highest rates observed. Taxonomic and functional gene data suggested that other microbial guilds that influence carbon and nitrogen cycling need to be accounted for to better predict CH4 fluxes at landscape scales. Higher methane production occurring near the freshwater boundary with slight salinization (and sulfate incursion) might result from increased sulfate-reducing fermenter and syntrophic populations, which can produce substrates used by methanogens. Moreover, higher salinities can solubilize ionically bound ammonium abundant in the lower salinity wetland soils examined here, which could inhibit methanotrophs and potentially contribute to greater CH4 fluxes observed in oligohaline sediments.IMPORTANCELow-level salinity intrusion could increase CH4 flux in tidal freshwater wetlands, while higher levels of salinization might instead decrease CH4 fluxes. High CH4 emissions in oligohaline sites are concerning because seawater intrusion will cause tidal freshwater wetlands to become oligohaline. Methanogenesis genes alone did not account for landscape patterns of CH4 fluxes, suggesting mechanisms altering methanogenesis, methanotrophy, nitrogen cycling, and ammonium release, and increasing decomposition and syntrophic bacterial populations could contribute to increases in net CH4 flux at oligohaline salinities. Improved understanding of these influences on net CH4 emissions could improve restoration efforts and accounting of carbon sequestration in estuarine wetlands. More pristine reference sites may have older and more abundant organic matter with higher carbon:nitrogen compared to wetlands impacted by agricultural activity and may present different interactions between salinity and CH4. This distinction might be critical for modeling efforts to scale up biogeochemical process interactions in estuarine wetlands.

The San Francisco Estuary (estuary) and the Sacramento–San Joaquin Delta (the Delta) in California face significant challenges in managing water resources during extended droughts. Zooplankton are a vital trophic link between phytoplankton producers and higher-level consumers such as predatory zooplankton and fish. However, there is still much to be learned about what drives zooplankton abundance and how they respond to drastic changes in environmental conditions, such as droughts. We found that during drought years zooplankton abundance and distribution changes varied for examined taxa. Significant declines in the abundance of Daphnia spp. and the copepod Pseudodiaptomus forbesi occurred in the Suisun Marsh and Suisun Bay regions. In contrast, abundance of the non-native copepod Limnoithona tetraspina increased in Suisun Marsh and the South-Central Delta during those same drought conditions. Salinity is a strong determinant of the presence and abundance of the studied taxa, and we showed that changes in the distribution of salinity as a result of low outflow conditions were an important factor in the regional abundance of zooplankton. Because of the expected increase in the frequency and severity of regional droughts, understanding how these conditions affect zooplankton in the estuary will benefit scientists and resource managers who aim to improve conditions for native fishes.

Droughts have major effects on estuaries because freshwater entry is one of the defining features of an estuary, and freshwater flow is an important variable that determines the interannual change in the environment. In the upper San Francisco Estuary (the Sacramento–San Joaquin Delta, Suisun Bay, and Suisun Marsh), the Mediterranean climate includes frequent multi-year droughts. To assess ecosystem responses to droughts in the upper estuary, the Interagency Ecological Program Drought Synthesis Team assembled a set of flow, water quality, chlorophyll, zooplankton, and fish data from 1975 to 2021 to test for differences between multi-year droughts and multi-year wet periods and tested for linear relationships between each variable and the Sacramento Valley Hydrologic Index (see definitions and relationships as outlined in Appendix A). Our models showed droughts decreased Delta outflow, project exports, zooplankton in Suisun Bay, and some fish species. We also found that droughts increased water clarity, salinity, nutrients, chlorophyll in the South Delta, zooplankton in the South Delta, and water residence time. Although our analyses only tested correlations, we hypothesized that most of the food-web responses could be traced to increased residence time, decreased transport rates, or both. However, some responses may have been caused by secondary effects, including shifts in salinity gradients, regional changes in water quality, or differences in top-down effects of increased predation and grazing rates. With increased frequency of droughts in the future, this increasingly low-outflow, warming, clearing estuary—which is invaded by non-native species and has low pelagic fish production—is rapidly becoming the new “normal.”

Low salinity Waterflooding (LSWF) is a proven EOR technique which has emerged in the last few decades. In this, the salinity of the injected water is reduced. Studies have unveiled that the LSWF can improve about 5–38% of oil recovery. This work aims to study the effectiveness of LSWF by modeling Sea waterflooding (SWF) and LSWF using a commercial reservoir simulator and justifying the proposed mechanisms responsible for the incremental oil recovery due to LSWF. A critical parametric study has been undertaken, which led us to conclude that LSWF is a cost-effective, and environment-friendly method that results in additional oil recovery for sandstone reservoirs. [ABSTRACT FROM AUTHOR]

Zinc (Zn) deficiency and salt stress are well-known soil problems and often happen parallelly in cultivated soils. In this study, Zn-amino acid complexes (Zn-AAc) were used as a source of Zn to determine their effects on salt-induced damage in wheat plants. The bread wheat (Triticum aestivum L. cvs. Kavir) was supplied with Zn-glycine (Zn-Gly), Zn-alanine (Zn-Ala), and ZnSO4 as Zn sources at three salinity levels (EC 2, 4 and 6 dS m-). Salinity caused a significant decrease in shoot dry matter and grain yield of wheat, but this negative effect was significantly improved by the application of Zn-AAc. Salt stress decreased shoot and grain Zn concentration, but this reduction was lower in plants supplied by Zn-AAc. Calcium (Ca) and potassium (K) concentrations were increased in a shoot by salinity stress while decreased in grain. Sodium (Na) concentration decreased in shoot and grain by using Zn-AAc. At all of the salinity levels, wheat supplied with Zn-AAc had lower lipid peroxidation compared to those grown under the ZnSO4 source. Application of Zn-AAc increased the activities of catalase (CAT) and superoxide dismutase (SOD) in the roots of wheat plants in saline conditions. Based on the results, the adverse effects of salinity stress on wheat plants can moderately improve with Zn-AAc application. [ABSTRACT FROM AUTHOR]

SUMMARY: Mangroves grow in tropical/subtropical intertidal habitats with extremely high salt tolerance. Trehalose and trehalose‐6‐phosphate (T6P) have an alleviating function against abiotic stress. However, the roles of trehalose in the salt tolerance of salt‐secreting mangrove Avicennia marina is not documented. Here, we found that trehalose was significantly accumulated in A. marina under salt treatment. Furthermore, exogenous trehalose can enhance salt tolerance by promoting the Na+ efflux from leaf salt gland and root to reduce the Na+ content in root and leaf. Subsequently, eighteen trehalose‐6‐phosphate synthase (AmTPS) and 11 trehalose‐6‐phosphate phosphatase (AmTPP) genes were identified from A. marina genome. Abscisic acid (ABA) responsive elements were predicted in AmTPS and AmTPP promoters by cis‐acting elements analysis. We further identified AmTPS9A, as an important positive regulator, that increased the salt tolerance of AmTPS9A‐overexpressing Arabidopsis thaliana by altering the expressions of ion transport genes and mediating Na+ efflux from the roots of transgenic A. thaliana under NaCl treatments. In addition, we also found that ABA could promote the accumulation of trehalose, and the application of exogenous trehalose significantly promoted the biosynthesis of ABA in both roots and leaves of A. marina. Ultimately, we confirmed that AmABF2 directly binds to the AmTPS9A promoter in vitro and in vivo. Taken together, we speculated that there was a positive feedback loop between trehalose and ABA in regulating the salt tolerance of A. marina. These findings provide new understanding to the salt tolerance of A. marina in adapting to high saline environment at trehalose and ABA aspects. Significance Statement: We identified an important salt‐tolerant gene (AmTPS9A) in mangrove Avicennia marina and proposed a hypothesized model in which ABA and trehalose synergistically regulate salt tolerance in A. marina. Our study provides new insights into the salt tolerance of mangrove A. marina at the aspect of the trehalose pathway. [ABSTRACT FROM AUTHOR]

Salicylic acid (SA) and melatonin (MEL) are affordable and effective phytohormones that help mitigate environmental stress. However, the combined benefits of SA and MEL in managing salt and drought stress in lettuce have not been evaluated. Therefore, this study was designed to evaluate the effectiveness of foliar spraying with 1.0 mM SA and 100 µM MEL, either alone or in combination, to enhance lettuce yield, growth, photosynthetic pigments, mineral status, quality, and antioxidant response under four different irrigation regimes. The irrigation practices used were: full irrigation (FI, irrigated with 0.18 dS m −1 at 100 % field capacity [FC]), deficit irrigation (DI, irrigated with 0.18 dS m −1 at 75 % FC), saline irrigation (SW, irrigated with 2.5 dS m −1 at 100 % FC), and deficit saline irrigation (DSW, irrigated with 2.5 dS m −1 at 75 % FC). Additionally, a control treatment (CK) was carried out with foliar application of distilled water and irrigation at 0.18 dS m −1. Compared to the CK, the application of SA, MEL, and SA+MEL increased evapotranspiration by 4.3 %, 8.6 %, and 15.1 %, and yield by 10.2 %, 16.4 %, and 23.8 %, respectively, under FI conditions. Furthermore, the joint application of SA and MEL at FI showed 25.3 % and 20.2 % higher K +/Na+ and Ca2+/Na+ ratios, respectively, compared to the CK. Additionally, the co-application of SA+MEL improved chlorophyll a, b, and carotenoid levels by 19.2 %, 17.2 %, and 20.4 %, respectively, under FI conditions, compared to the CK. Exogenous application of SA, MEL, and SA+MEL also improved total soluble solids by 17.3 %, 18.5 %, and 11.1 % and reduced nitrate content by 9.7 %, 10.4 %, and 13.5 % in lettuce under FI conditions, compared to the CK. The application of SA+MEL together resulted in a more pronounced increase in vitamin C content compared to supplying SA and MEL individually. Moreover, under DSW conditions, exogenous application of SA, MEL, and SA+MEL decreased the membrane stability index by 13.7 %, 9.4 %, and 6.3 %, increased malondialdehyde by 65.4 %, 40.8 %, and 36.6 %, and increased proline content by 68.4 %, 65.4 %, and 96.4 %, respectively, compared to the CK. Moreover, exogenous SA+MEL significantly increased the activities of superoxide dismutase, catalase, peroxidase enzymes under both SW and DSW conditions compared to the SA or MEL. Conversely, the activity of ascorbate peroxidase enzyme showed a gradual decrease in DI, SW, and DSW conditions, relative to the FI conditions. In conclusion, the integrated application of SA+MEL is an optimal strategy to enhance yield, morpho-physiological traits, nutrient homeostasis, antioxidant capacity, and quality in lettuce and mitigate the adverse effects of drought, salinity, and drought-salinity stress. [Display omitted] • Deficit saline irrigation has the most adverse effect on lettuce yield. • SA and MEL enhanced lettuce tolerance to drought and salinity stress. • Joint use of SA (1.0 mM) and MEL (100 µM) more effectively alleviates stress in lettuce. • SA+MEL improved the nutrient homeostasis and antioxidant capacity of lettuce. • SA+MEL combination increased vitamin C and decreased the nitrate content of lettuce. [ABSTRACT FROM AUTHOR]

Creeping savory is a wild plant that is used for comestible consumption, preparation of beverages, and production of sanitary ware and herbal drugs. To investigate the effects of salinity stress and salicylic acid on antioxidant enzymes, photosynthetic pigments, relative water content, proline, and soluble protein content in S. spicigera a factorial experiment was conducted based on a Completely Randomized Design (CRD) and three replications. The experiment was implemented at the greenhouse of Agriculture and Natural Resources Research and Education Center of Kermanshah, Iran (2019). Experimental treatments were four levels of salinity (0-50-100-150 mM NaCl) and two levels of salicylic acid (0 and 2 mM). Results showed that increasing salinity levels caused a significant reduction in relative water content, leaf fresh weight, leaf dry weight, chlorophyll a, chlorophyll b, total chlorophyll, and carotenoid content. Salinity drastically enhanced the antioxidant activities (SOD, POD, and CAT), and cell proline content. Salicylic acid considerably decreased proline content under salt stress conditions, but improved antioxidant activities of SOD, POD, and CAT, and enhanced chlorophyll a, chlorophyll b, total chlorophyll, carotenoid content, protein content, relative water content, and leaf fresh weight under salt stress. Salicylic acid reduced the destructive effect of salinity on some morphological, physiological, and biochemical characteristics in creeping savory. [ABSTRACT FROM AUTHOR]

Salinity tolerance requires coordinated responses encompassing salt exclusion in roots and tissue/cellular compartmentation of salt in leaves. We investigated the possible control points for salt ions transport in roots and tissue tolerance to Na+ and Cl– in leaves of two contrasting mungbean genotypes, salt‐tolerant Jade AU and salt‐sensitive BARI Mung‐6, grown in nonsaline and saline (75 mM NaCl) soil. Cryo‐SEM X‐ray microanalysis was used to determine concentrations of Na, Cl, K, Ca, Mg, P, and S in various cell types in roots related to the development of apoplastic barriers, and in leaves related to photosynthetic performance. Jade AU exhibited superior salt exclusion by accumulating higher [Na] in the inner cortex, endodermis, and pericycle with reduced [Na] in xylem vessels and accumulating [Cl] in cortical cell vacuoles compared to BARI Mung‐6. Jade AU maintained higher [K] in root cells than BARI Mung‐6. In leaves, Jade AU maintained lower [Na] and [Cl] in chloroplasts and preferentially accumulated [K] in mesophyll cells than BARI Mung‐6, resulting in higher photosynthetic efficiency. Salinity tolerance in Jade AU was associated with shoot Na and Cl exclusion, effective regulation of Na and Cl accumulation in chloroplasts, and maintenance of high K in root and leaf mesophyll cells. Summary statement: Salinity tolerance in mungbean is related to its ability to intercept Na and Cl in roots, thereby reducing Na and Cl transport to shoot, effectively regulate Na and Cl accumulation in chloroplasts, and maintain high K in root and leaf mesophyll cells. [ABSTRACT FROM AUTHOR]

Salinity drastically hampers the germination and growth of legumes including mungbean which jeopardizes the food and nutritional security of the rising human population. An experiment entailing varying salinity levels (0, 50, and 150 Mm NaCl) was conducted to investigate the response of salinity on germination and seedling growth of four mungbean genotypes (BARI Mung-7, BARI Mung-8, BU Mug-2, and BU Mug-4). The germination indices such as percentage and rate of germination along with the coefficient of velocity (GP) of all mungbean genotypes were significantly reduced by the salt stress, especially of Binamoog-5 at 150 mM NaCl. Contrarily, BARI Mung-8 remained superior by recording better germination indices under all salinity levels. The same cultivar outperformed the rest of the cultivars based on the greatest weights (fresh and dry) and length of roots and shoots, while BU Mug-2 could not perform at par under a saline environment. Thus, it might be inferred that mungbean genotypes differ in their potential for salt endurance due to the germination vigor and seedling growth robustness and screening of salt-tolerant cultivars could mitigate the detrimental effects of saline environment. [ABSTRACT FROM AUTHOR]

Agricultural land, water, and fertilizer utilization significantly impact the nutrient and water balances and greenhouse gas (GHG) emissions. This study explores the impacts of agricultural water, land, and fertilizer management on the trade-offs between economic benefit, GHG emissions, and water, salinity, nitrate, and phosphate balances by employing crop growth, flow, and solute simulation models, linked with an optimization algorithm. The coupled models can simulate flow, crop growth, and nutrient transport, and capture the water and solutes interaction between the farmland soil zone and saturated groundwater zone, while considering spatial heterogeneity of soil, crop, fertilizer, and irrigation. The optimization model was used to find the trade-offs between the conflicting objectives of maximizing the net economic benefit and minimizing GHG emissions. The optimal water and land allocation schemes, fertilizer application, and crop type were obtained under wet, normal, and dry hydrological years. Then a simple rule was introduced based on the optimum results of the wet, normal and dry years. The proposed methodology was applied to the Dashteabbas irrigation network in southwest Iran. The results showed that the mass loading of salt, nitrate and phosphate decreases to water bodies by 7%, 37%, and 37%, respectively, and less land (−19%), water (−16%), and fertilizer (−35%) are exploited. Also, despite the lower net benefit of the optimum solution (12% lower than the current situation), the GHG emissions (28% lower than the current situation) would decrease, indicating that the introduced rule can help decision-makers to promote coordinated economic and environmental development in the agricultural irrigation systems. [ABSTRACT FROM AUTHOR]

Soil acidity and salinity stress significantly affect nutrient availability and uptake, as well as the growth, development, and yield of maize plants. This research aimed to screen, characterize, and assess the ability of selected indigenous biofilm-forming rhizophosphate bacteria (BFRB) to produce growth factor and promote maize growth. Soil samples were collected from both acid ecosystems (AE) and saline ecosystems (SE). Thirty isolates of rhizophosphate bacteria were obtained based on the clear zone around colonies on selective Pikovskaya agar media. Subsequently, a qualitative biofilm test was conducted, resulting in the identification of 9 isolates of biofilm-forming rhizophosphate bacteria. Biochemical test was performed to asses phosphate solubility index (PSI) and production of indole acetic acid (IAA) and biological assays was performed to measure the effect of selected BFRB on maize growth characteristics. The experiment was arranged in a randomized block design with 10 treatments (control and 9 isolates of BFRB) and 3 replications. The findings revealed that all isolate has avaibility to membentuk biofilm dan mampu melarutkan P. three potential isolates of BFRB from both AE and SE significantly enhanced maize growth. Isolates PS-03, PN-05, and PC-04 from saline soils, as well as isolates NA-01, NG-04, and NF-04 from acid land, exhibited notable increases in root length, plant height, and dry weight compared to the control. For instance, isolates PS-03, PN-05, and PC-04 from saline soils increased maize height by 2160.87% and root length by 392.64%, and they also increased the dry weight of the plants by 20.50%. Similarly, isolates NA-01, NG-04, and NF-04 from acid soil increased maize height by 673.82% and root length by 220.29%, and they increased the dry weight of the plants by 12.57%. These findings suggest that these BFRB isolates hold significant potential for developing rhizophosphate biofilm biofertilizers to enhance maize productivity in marginal soils. Additionally, each of these bacteria produced IPF and IAA, which contributed to the significant increases in plant height and root length, and formed biofilms that were present on the roots of the maize plants. Therefore, field trials are necessary to utilize these biophosphate fertilizers to improve fertilization efficiency and maize productivity in saline and acidic ecosystems. [ABSTRACT FROM AUTHOR]

Identification of potential lands on the basis of their environmental benefits and constraints can greatly contribute to the stability of canola production in different parts of the world including Sistan-Baluchestan province, Iran. Accordingly, using GIS, the scores of environmental factors affecting canola production including temperature, rainfall, slope, altitude, organic matter, soil salinity, pH and soil nutrients (N, P, K, Fe and Zn) were integrated along with the weights of analytical hierarchical process (AHP) for the production of canola suitability maps. The zoning maps of climate, topography, and soil as well as the canola suitability maps and the current production maps of canola were prepared. According to the AHP results canola cultivation was affected the most by climate (rainfall and water sources) compared with topography and soil. ArcGIS results indicated southern lands of Zahedan had the highest organic matter, and excluding Hirmand, other parts of the area had appropriate salinity for canola production. The most appropriate areas in terms of acidity for canola production are Hirmand and the central part of Zahedan. In arable soil, the nitrogen level was not maximum in the region, and Nimrooz and Zabol had the highest phosphorus. Potassium was average in the research area, and Zabol, Zahak, Nimrooz and Hamoon had the highest Fe. The output maps obtained from the combination of various ecological factors indicated that the moderate and non-suitable classes of land for canola cultivation are located in the northern parts of Zahak, Hamon, Nimzoz and the total lands of Hirmand and Zabol. [ABSTRACT FROM AUTHOR]

Salinity is one of the main factors influencing the early life stages of fish along an estuary, which shows great temporal and spatial changes. Recently, remote sensing has been widely applied to map salinity changes and fuzzy logic is identified as a suitable and strong tool for modeling complex systems. Based on collections of fish larvae and juveniles and water parameters in May, September, November, and December during 2019 along the Ba Lat estuary of the Red River, northern Vietnam, the present study attempts to predict the mapping and monitoring of the salinity using multispectral satellite imagery from Landsat 8 OLI satellite. The study determined that the NFS machine learning model, when improved by PCA, achieved a higher performance in displaying different salinity levels. The present study also confirms that using high spatial resolution or hyperspectral images would have increased the accuracy of spatial variation in similar modeling and mapping. Fuzzy rule–based modelling suggests that the occurrence of fish larvae and juveniles depended on salinity levels, with an R2 > 0.9, compared to the field surveys. This finding further confirms the accuracy data obtained by artificial neural network models. [ABSTRACT FROM AUTHOR]

Barley (Hordeum vulgare) is the fourth largest cereal crop in the world, with considerable nutritional value. Recently more studies on the toleration of barley to salt stress have been published, indicating an increased concern for food safety. Salt stress is an increasing threat to agricultural productivity; thus, an attempt was made to explore the growth-promoting capacities of an endophytic fungal strain Aspergillus niger CSR3 in H. vulgare. In the current study, we investigated various physiological and biochemical characteristics of two H. vulgare varieties, namely OM-80 and OM-82, under 300 mM NaCl and 100% seawater treatments with and without the inoculation of CSR3. Our results showed that biopriming of H. vulgare seeds with CSR3 enhanced germination ratio both in control and salt treated conditions. Under salt stress, the growth of H. vulgare plants was significantly reduced; however, CSR3 alleviated the salt stress and significantly increased root/shoot length and weight compared to their respective counterparts both under control and stress conditions. The fungal strain showed an ameliorated response to salt stress by improving the photosynthetic machinery. Results demonstrate that accumulation of reduced glutathione (GSH), catalase (CAT), and flavonoids decreased in inoculated plants as compared to non-inoculated under saline conditions indicating the potential of CSR3 in maintaining cellular homeostasis against salinity stress. Moreover, our finding also revealed that starch accumulation decreased with a gradual increase of salt treatment; however, CSR3 inoculation enhanced starch and decreased sugar level, indicating its potential to convert excess sugar to starch. In conclusion, CSR3 can improve plant performance significantly and can greatly improve sustainable agricultural production in saline marginal lands. [ABSTRACT FROM AUTHOR]

Abiotic stresses such as salinity, submergence, drought and extreme temperatures greatly affect rice production worldwide. Marker-assisted selection was effectively used to introgress QTLs for salinity tolerance (Saltol) and submergence tolerance (Sub1) into the background of elite rice variety Jyothi. Saltol introgressed BC1F2 lines of Jyothi with 79.3% of recipient parent genome was crossed with Sub1 introgressed BC2F2 lines of Jyothi showing 95.9% of parent genome recovery. F1 progenies were screened with Saltol and Sub1 linked foreground markers and recombinant markers. F1 heterozygous plants were selfed to produce F2 generation. F2 progenies homozygous for both the loci were selected. Phenotypic screening for salinity and submergence tolerance was performed to validate the introgressed genes. The plants able to tolerate both salinity and submergence stresses were selected for selfing to raise F3 progenies. The pyramided lines were also similar to recurrent parent in agro-morphological and grain quality traits. [ABSTRACT FROM AUTHOR]

Azadirachta indica or neem is recognized for its unique properties, both against insects and in improving human health. However, proteomics studies of this plant's response to abiotic stresses have yet to be reported. Application of this technique highly depends on efficient and optimized sample preparation, in deriving highly reproducible proteomics data. The present study highlights the comparison of protein extraction method which effectively recovers proteins from recalcitrant phenolic-rich tissues of neem callus. Four protocols based on TCA-acetone or/and phenol extraction methods were compared. The TCA-acetone complemented with PVPP method was the most effective approach and generated the greatest total protein yields, spot number, good resolution, and spot intensities. Subsequently, the differential proteomics performed revealed that proteins associated with oxidoreduction, energy, transcriptional, stress response, respiration, and cell division were differentially regulated in salinity stress treatment. Meanwhile, the expression of proteins classified in the group of energy, photosynthesis, protein synthesis, oxidoreduction, and post-transcriptional regulation was altered in the JA-stressed callus. The accumulation of AZA was also noticeably reduced in salinity- and JA-treated callus, suggesting these tested stress parameters were not effective in improving AZA production in the neem callus. Overall, this analysis provides valuable information on the application of plant tissue culture as an alternative for sustainable production of major bioactive constituents in A. indica. Together, the proteomics results brought forward a possible fundamental representation of the mechanism associated with salinity and JA tolerance in the neem callus. [ABSTRACT FROM AUTHOR]

Mangroves have unique adaptations that help them survive in highly saline and hypoxic environments. The present study examines how two mangrove species, namely Kandelia candel (L.) Druce and Rhizophora mucronata Lam., well known for their ultrafiltration capability, responded to different salinity levels. We have conducted histochemical, biochemical and gene expression analyses of lignin and cell wall components from the two non-salt-secreting mangrove species treated with different salinity gradients. Root length decreased at higher salinity treatments for K. candel (11.7–13.8 cm in freshwater; 5.7–6.7 cm at 20 ppt), while R. mucronata (4.9–6.4 cm in freshwater; 5.5–9.4 cm at 35 ppt) showed no significant change. The rate of lignin deposition near the vascular bundles varied from freshwater to salt treatments and between the species. Overall lignin content in the K. candel roots increased at higher salinity (40.6–70.6 µg/mg at freshwater to 53.9–145.1 µg/mg at 20 ppt). At the same time, R. mucronata showed comparatively higher lignin content (101.4–149.6 µg/mg) than K. candel (40.6–145.1 µg/mg). Total pectin concentration increased after 60 days in K. candel at freshwater (55.7–199.82 µg/mg) and salt treatments (90.0–210.5 µg/mg at 20 ppt). But pectin content decreased after 60 days of treatment in R. mucronata. A similar trend was observed for total carbohydrates and cellulose. Overall, hemicellulose concentration was low in R. mucronata compared to K. candel. Total polyphenol content was higher in R. mucronata (308.1–731.1 µg GAE/mg DW) than in K. candel (43.1–400.4 µg GAE/mg DW). Higher gene expression of lignin biosynthesis genes viz CAD, HCT, C3H, COMT and peroxidase was observed in R. mucronata at 5 ppt salinity 60 days after treatment. The results of this study will help explain the role of root lignification in mangrove salinity tolerance mechanisms. [ABSTRACT FROM AUTHOR]

Seagrasses have long been a focal point for management efforts aimed at restoring ecosystem health in estuaries worldwide. In Tampa Bay, Florida (USA), seagrass coverage has declined since 2016 by nearly a third (11,518 acres), despite sustained reductions of nitrogen loads supportive of light environments for growth. Changing physical water quality conditions related to climate change may be stressing seagrasses beyond their optimal growth ranges, requiring an assessment to determine if this decline can be linked to climate stress. Three ambient water quality datasets of varying sampling designs and coverage were evaluated to characterize physicochemical environments in Tampa Bay and the potential relationships with seagrass change. Tampa Bay has become hotter and fresher with water temperature increasing by 0.03–0.04 °C per year and salinity decreasing by 0.04–0.06 ppt per year, translating to an increase of 1.3 to 1.7 °C and a decrease of 1.6 to 2.6 ppt over the last 50 years. Additionally, the number of days when temperature was above 30 °C or salinity was below 25 ppt has increased on average across all bay segments by 48 and 37 days, respectively, since 1975. These changes varied spatially and seasonally, with the most dramatic changes observed in the upper bay. Generalized Additive Models provided a weight-of-evidence that recent seagrass declines are somewhat associated with hotter and fresher conditions. Trends in warming and increased precipitation in the region are likely to continue, further creating suboptimal conditions for seagrasses in Tampa Bay. These results should compel resource managers to consider the likelihood that reduced resilience of estuarine resources due to shifting ecological baselines driven by additional climate change drivers will complicate long-standing management paradigms. While conventional management approaches that focus on limiting nutrient loads should be continued, their future effectiveness may be confounded by climate change drivers and warrant additional, complementary interventions and continuous monitoring data to support ecosystem health into the future. [ABSTRACT FROM AUTHOR]

Purpose: Environmental stresses are a main disturbing factor influencing horticultural productivity around the world. It will affect all plants including resistant or non-resistant cultivars. So, it is important to find the better cultivars and to check the response to adverse environmental conditions. Research method: Thus, the present research was conducted to evaluate responses of different bearing status of pistachio cultivars including Kalleh-Ghochi (K), Ohadi (O) and Ahmad-Aghaii (A), grafted on Badami-Rize-Zarand as rootstock, for six consecutive years to soil salinity. Findings: ONbearing trees of 'Ahmad-Aghaii' showed the highest yield, followed by 'Ohadi' and 'Kalleh-Ghochi'. In addition, the lowest leaf temperature was observed with this cultivar. Although the highest nitrogen, sodium, carbohydrate, peroxidase and leaf temperature was obtained in ON-bearing trees, however, the lowest potassium and total phenol content indicated in OFF-bearing status. It was found a negative correlation between leaf potassium content and ABI, between leaf peroxidase activity and ABI and between leaf temperature and ABI. On the other hand, leaf temperature increased as leaf sodium content increased. Research limitations: There was no limitation. Originality/Value: From data presented here, it is concluded that salinity and Na accumulation might be effective in changing the response of the pistachio cultivar under harsh environmental conditions which affects yield component and alternate bearing index. [ABSTRACT FROM AUTHOR]

In-situ measurements of ocean temperature and salinity are critical to ocean-related studies but are limited in space and time. Satellite retrievals provide high-resolution, globally-covered sea surface temperature (SST), salinity (SSS) and cannot directly measure the subsurface information., and height (SSH), but are limited to the ocean surface and cannot directly measure the subsurface information. Here we design a physics-informed algorithm that can reconstruct the vertical distributions of upper ocean temperature and salinity based purely on satellite observations. The algorithm stresses the tight ocean surface-subsurface coupling and the co-variability of ocean temperature and salinity. It is firstly tested with climate model simulations and then validated with actual observations by Argo floats, moored buoys and multiple ocean reanalysis datasets. The resultant satellite-based upper ocean temperature and salinity dataset has a global coverage, a high spatial resolution, and resolves ocean thermohaline structure from surface to 400 m. This dataset complements existing ocean subsurface products as an independent satellite-based observational dataset. The success of our reconstruction algorithm highlights a pressing need to maintain and advance the satellite observations of SST, SSS, and SSH. The reconstructed ocean temperature and salinity dataset can be accessed at https://doi.org/10.5281/zenodo.13145129 (Liu, 2024) and be used by researchers to study mesoscale ocean phenomena, assess the ocean heat content in various sea areas and etc. [ABSTRACT FROM AUTHOR]

Soil salinity is a major abiotic stress that limits the growth and productivity of horticultural crops. Most fruit crops are glycophytes, and their production is adversely affected by salt stress. The key findings indicate that salinity reduces several plant growth parameters such as shoot and root length, number of leaves, plant biomass and relative water content as well as biochemical parameters such as photosynthetic pigments and proline. Physiological results show decreased water absorption, nutrient imbalances such as changes in ion concentrations and hormone levels and increased oxidative stress. Several mitigation strategies are recommended, such as the use of salt-tolerant rootstocks, application of growth regulators and soil amendments to enhance salt tolerance in tropical fruit crops. This review concludes that integrating physiological and agronomic strategies is essential for mitigating the adverse effects of salinity on tropical fruits. [ABSTRACT FROM AUTHOR]

Manufacturing a multilayer evaporator with a delicate structure and removing salt accumulation during prolonged operation are challenges in seawater desalination. A flexible single‐layer salt‐rejecting monolithic porous evaporator (SRMPE) is presented that floats on the near surface of seawater without any support structure. The hydrophilic component of this network polymer modulates the water association state in SRMPE, achieving a high evaporation rate of 3.47 kg m−2 h−1 and an efficiency of 94.3%. With a large capillary water flux (14.4 L m−2 h−1), the SRMPE exhibits superior and rapid self‐cleaning by removing sodium chloride (NaCl) powder (33% by weight) within 1.25 h in simulated seawater (salinity, 3.5%) under 1 sun radiation. Furthermore, even after continuous irradiation for 12 h in highly concentrated brine (25% salinity), no salt crystallizes on the evaporator surface. It may stimulate creative work by scientists and engineers in the design of simple, highly efficient salt‐rejecting, self‐cleaning interfacial solar evaporators. [ABSTRACT FROM AUTHOR]

The depletion of freshwater resources, as well as climate change and population growth, are threatening the livelihoods of thousands of people around the world. The introduction of underutilized crops such as quinoa may be important in countries with limited productivity and/or limited access to water due to its resistance to different abiotic stresses and its high nutritional value. The aim of this review is to assess whether techniques such as germination, malting and fermentation would improve the nutritional and bioactive profile of quinoa. The use of nitrogen oxide-donating, oxygen-reactive and calcium-source substances increases germination. The ecotype used, temperature, humidity and germination time are determining factors in germination. The presence of lactic acid bacteria of the rust-type phenotype can improve the volume and texture during baking of the doughs, increase the fiber content and act as a prebiotic. These techniques produce a significant increase in the content of proteins, amino acids and bioactive compounds, as well as a decrease in anti-nutritional compounds. Further studies are needed to determine which conditions are the most suitable to achieve the best nutritional, functional, technological, and organoleptic quinoa properties. [ABSTRACT FROM AUTHOR]

This article explores the impact of salinity on two different maize cultivars and their ability to tolerate salt stress. The study reveals that the more salt-tolerant cultivar is better at excluding sodium (Na+) and retaining potassium (K+), which are crucial for minimizing Na+ uptake. The researchers also discovered that the salt-tolerant cultivar experienced a net influx of hydrogen ions (H+) under severe salt stress, while the salt-sensitive cultivar did not. This suggests that net H+ influx is an important but often overlooked trait in salt tolerance. Additionally, the study found that K+ efflux and Na+ influx help maintain charge balance during H+ influx. [Extracted from the article]

Dissolved organic carbon (DOC) released by macroalgae supports coastal ocean carbon cycling and contributes to the total oceanic DOC pool. Salinity fluctuates substantially in coastal marine environments due to natural and anthropogenic factors, yet there is limited research on how salinity affects DOC release by ecologically important macroalgae. Here we determined the effect of short‐term salinity changes on rates of DOC release by the habitat‐forming fucalean seaweed Sargassum fallax (Ochrophyta). Lateral branches (~4 g) cut at the axes of mature individuals were incubated across a salinity gradient (4–46) for 24 h under a 12:12 light:dark cycle, and seawater was sampled for DOC at 0, 12, and 24 h. Physiological assays (tissue water content, net photosynthesis, respiration, tissue carbon, and nitrogen content) were undertaken at the end of the 24‐h experiment. Dissolved organic carbon release increased with decreasing salinity while net photosynthesis decreased. Dissolved organic carbon release rates at the lowest salinity tested (4) were ~3.3 times greater in the light than in the dark, indicating two potential DOC release mechanisms: light‐mediated active exudation and passive release linked to osmotic stress. Tissue water content decreased with increasing salinity. These results demonstrate that hyposalinity stress alters the osmotic status of S. fallax, reducing photosynthesis and increasing DOC release. This has important implications for understanding how salinity conditions encountered by macroalgae may affect their contribution to the coastal ocean carbon cycle. [ABSTRACT FROM AUTHOR]

Salinity is a significant threat that causes considerable yield losses in date palm. The root endophytic fungus Piriformospora indica has proven effective in providing salt stress tolerance to host plants. However, the underlying molecular mechanism facilitating the date palm's response to P. indica inoculation, and its involvement in the salt stress tolerance, remains unknown. In this study, the colonization of P. indica on date palm seedlings exposed to saline conditions was observed through confocal microscopy, and its impact on gene expressions was evaluated using the transcriptomic analysis. Our findings show that P. indica colonization reinforced the cortical cells, prevented them from plasmolysis and cell death under salinity. The RNAseq analysis produced clean reads ranging from 62,040,451 to 3,652,095 across the treatment groups, successfully assembling into 30,600 annotated genes. Out of them, the number of differentially expressed genes (DEGs) varied across the treatments: i.e., 2523, 2031, and 1936 DEGs were upregulated, while 2323, 959, and 3546 were downregulated in Salt, Fungi, and Fungi+Salt groups, respectively. Furthermore, principal component analysis based on transcriptome profiles revealed discrete clustering of samples from different treatment groups. KEGG and GO pathways enrichment analysis highlighted variation in the number and types of enriched pathways among the treatments. Our study indicated variations in gene expression related to plant hormone biosynthesis and signal transduction (auxin, abscisic acid, gibberellin, and ethylene), ABC transporters, sodium/hydrogen exchanger, cation HKT transporter, transcription factors such as WRKY and MYBs, and the plant immune system (lipoxygenase and jasmonate) of the date palm seedlings. By characterizing the transcriptome of date palm roots under salt stress and with colonization of P. indica, the present findings provide valuable perspectives on the molecular mechanisms responsible for inducing salinity stress tolerance in plants. [ABSTRACT FROM AUTHOR]

Zostera japonica (Z. japonica), the most widely distributed seagrass species in temperate estuaries, has experienced a dramatic decline of nearly 75% over the past decade. While previous research has investigated the adaptation of seagrass individuals and populations to single stress factors, the molecular mechanisms underlying the interaction of multiple stressors remain poorly understood. This study conducted laboratory experiments to examine the response of Z. japonica at different life stages to environmental pressures, specifically salinity and turbidity, as indicated by changes in free amino acids (FAAs). The results demonstrate that Z. japonica exhibits stronger adaptability to high salinity environments but displays weaker adaptability to freshwater conditions. Through single stress experiments, the salinity and turbidity thresholds for FAA homeostatic disturbance in Z. japonica were determined at seedling, juvenile, and mature stages. As Z. japonica matures, its metabolic pathways expand and diversify, allowing the regulation of key FAAs to enhance stress resistance. Turbidity stress exerts a more pronounced negative impact on the cellular homeostasis of Z. japonica compared to salinity stress, and when turbidity levels exceed 150 NTU, they significantly intensify the negative effects of salinity stress on the seagrass. Furthermore, under strong salinity-turbidity interactions, the concentration of key FAAs generally decreases by 20-30%, indicating inhibition of growth and development in Z. japonica. These findings have important implications for the conservation of intertidal seagrass beds and estuarine ecosystems in the face of multiple human activities and environmental stressors. The study provides valuable insights into the molecular mechanisms underlying Z. japonica's adaptations to salinity and turbidity stress, contributing to the development of targeted strategies to mitigate the impacts of environmental pressures on seagrass populations and promote the resilience of these critical marine ecosystems. [ABSTRACT FROM AUTHOR]

Microalgal lipids are precursors to the production of biodiesel, as well as a source of valuable dietary components in the biotechnological industries. So, this study aimed to assess the effects of nutritional (nitrogen, and phosphorus) starvations and salinity stress (NaCl) on the biomass, lipid content, fatty acids profile, and predicted biodiesel properties of green microalga Monoraphidium braunii. The results showed that biomass, biomass productivity, and photosynthetic pigment contents (Chl. a, b, and carotenoids) of M. braunii were markedly decreased by nitrogen and phosphorus depletion and recorded the maximum values in cultures treated with full of N and P concentrations (control, 100%). These parameters were considerably increased at the low salinity level (up to 150 mM NaCl), while an increasing salinity level (up to 250 mM NaCl) reduces the biomass, its productivity, and pigment contents. Nutritional limitations and salt stress (NaCl) resulted in significantly enhanced accumulation of lipid and productivity of M. braunii, which represented more than twofold of the control. Furthermore, these conditions have enhanced the profile of fatty acid and biodiesel quality-related parameters. The current study exposed strategies to improve M. braunii lipid productivity for biodiesel production on a small scale in vitro in terms of fuel quality under low nutrients and salinity stress. [ABSTRACT FROM AUTHOR]

Soil salinity poses a significant threat to agricultural productivity, impacting the growth and yield of wheat (Triticum aestivum L.) plants. This study investigates the potential of melatonin (MT; 100 µM) and hydrogen sulfide (H2S; 200 µM sodium hydrosulfide, NaHS) to confer the tolerance of wheat plants to 100 mM NaCl. Salinity stress induced the outburst of reactive oxygen species (ROS) resulting in damage to the chloroplast structure, growth, photosynthesis, and yield. Application of either MT or NaHS augmented the activity of antioxidant enzymes, superoxide dismutase, ascorbate peroxidase, glutathione reductase, and reduced glutathione (GSH) levels, upregulated the expression of Na+ transport genes (SOS1, SOS2, SOS3, NHX1), resulting in mitigation of salinity stress. Thus, improved stomatal behavior, gas-exchange parameters, and maintenance of chloroplast structure resulted in enhanced activity of the Calvin cycle enzymes and overall enhancement of growth, photosynthetic, and yield performance of plants under salinity stress. The use of DL-propargylglycine (PAG, an inhibitor of hydrogen sulfide biosynthesis) and p-chlorophenyl alanine (p-CPA, an inhibitor of melatonin biosynthesis) to plants under salt stress showed the comparative necessity of MT and H2S in mitigation of salinity stress. In the presence of PAG, more pronounced detrimental effects were observed than in the presence of p-CPA, emphasizing that MT was involved in mitigating salinity through various potential pathways, one of which was through H2S. [ABSTRACT FROM AUTHOR]

A tomato cultivar ('Izmir F1') grafted onto six commercially available rootstocks ('Arnold', 'Dohkko', 'Emperador', 'He-man', 'Kaiser', and 'Suzuka') together with self-grafted plants of the tomato cultivar (Izmir/Izmir) were included in a pot experiment. Growth, root morphology and nutrient uptake parameters were evaluated under different salinity conditions (0 and 50 mM NaCl). Grafting increases root length, specific root length, and root length ratio, which enhances the capabilities of hetero-grafted plants to exploit a larger volume of soil or otherwise increase root density under root restriction conditions. Since the root traits and nutrient concentrations in hetero-grafted variants were less impacted by a change in the salinity level, the use of specific rootstocks (‘Arnold,’ ‘Dohkko,’ ‘Kaiser’) could contribute to a steadier growth and yield of tomato plants under fluctuating salinity levels in the irrigation water. The hetero-grafted tomato plants (Dohkko/Izmir, Suzuka/Izmir) demonstrated higher Na sequestration/compartmentalization capabilities than the self-grafted (Izmir/Izmir) plants which helps to maintain a more appropriate K+/Na+ ratio. By exhibiting lower translocation indexes of some heavy metals (Al, Ni, Zn, and Cd), appropriate rootstock/scion combinations might be a useful tool for reducing the risk of their accumulation in edible plant organs. [ABSTRACT FROM AUTHOR]

Identifying how the demands of migration are met at the level of gene expression is critical for understanding migratory physiology and can potentially reveal how migratory forms evolve from nonmigratory forms and vice versa. Among fishes, migration between freshwater and seawater (diadromy) requires considerable osmoregulatory adjustments, powered by the ion pump Na+, K+-ATPase (NKA) in the gills. Paralogs of the catalytic α-subunit of the pump (NKA α1a and α1b) are reciprocally upregulated in fresh- and seawater, a response known as paralog-switching, in gills of some diadromous species. We tested ontogenetic changes in NKA α-subunit paralog expression patterns, comparing pre-migrant and migrant alewife (Alosa pseudoharengus) sampled in their natal freshwater environment and after 24 h in seawater. In comparison to pre-migrants, juvenile out-migrants exhibited stronger paralog switching via greater downregulation of NKA α1a in seawater. We also tested microevolutionary changes in the response, exposing juvenile diadromous and landlocked alewife to freshwater (0 ppt) and seawater (30 ppt) for 2, 5, and 15 days. Diadromous and landlocked alewife exhibited salinity-dependent paralog switching, but levels of NKA α1b transcription were higher and the decrease in NKA α1a was greater after seawater exposure in diadromous alewife. Finally, we placed alewife α-subunit NKA paralogs in a macroevolutionary context. Molecular phylogenies show alewife paralogs originated independently of paralogs in salmonids and other teleosts. This study demonstrated that NKA paralog switching is tied to halohabitat profile and that duplications of the NKA gene provided the substrate for multiple, independent molecular solutions that support a diadromous life history. [ABSTRACT FROM AUTHOR]

Estuaries are essential habitats for recreational and commercial fish that are shaped by both natural and anthropogenic processes. In Louisiana a combination of climate change and planned coastal restoration actions is predicted to increase freshwater introduction to coastal estuaries. As such there is a need to quantify the relationships between estuarine fish ecology and salinity to aid in predicting how species will respond to shifts in salinity. We investigated the relative abundance and dietary niches of adult (24.5 ± 5.4 cm standard length) spotted seatrout Cynoscion nebulosus across varying salinity regimes (oligohaline, mesohaline, and polyhaline) within Barataria Bay, Louisiana, using a combination of net sampling and gut content and stable isotopes analysis. We found that the relative abundance of C. nebulosus was lowest at the oligohaline site, translating to approximately five fewer fish captured for every single psu decrease in a site's average annual salinity. In contrast, we found that diets and, to a lesser extent, isotopic niches had a high degree of overlap across sites with differing salinity regimes. Fish and penaeid shrimp were the most common and important prey taxa recovered from guts at all sites. The small isotopic differences found among sites were likely due to spatial variation in hydrogeochemical baselines, and the observed isotopic overlap provides support for the idea that C. nebulosus move between adjacent salinity regimes and forage throughout Barataria Bay. Our results contribute to a greater understanding of the salinity preference and trophic ecology of C. nebulosus that can aid in predicting their responses to future salinity and habitat changes within Barataria Bay associated with predicted climate change and planned coastal restoration actions. [ABSTRACT FROM AUTHOR]

The Bay of Marseille (BoM), located in the northwestern Mediterranean Sea, is affected by various hydrodynamic processes (e.g., Rhône River intrusion and upwelling events) that result in a highly complex local carbonate system. In any complex environment, the use of models is advantageous since it allows us to identify the different environmental forcings, thereby facilitating a better understanding. By combining approaches from two biogeochemical ocean models and improving the formulation of total alkalinity, we develop a more realistic representation of the carbonate system variables at high temporal resolution, which enables us to study air–sea CO 2 fluxes and seawater p CO 2 variations more reliably. We apply this new formulation to two particular scenarios that are typical for the BoM: (i) summer upwelling and (ii) Rhône River intrusion events. In both scenarios, our model was able to correctly reproduce the observed patterns of p CO 2 variability. Summer upwelling events are typically associated with a p CO 2 decrease that mainly results from decreasing near-surface temperatures. Furthermore, Rhône River intrusion events are typically associated with a p CO 2 decrease, although, in this case, the p CO 2 decrease results from a decrease in salinity and an overall increase in total alkalinity. While we were able to correctly represent the daily range of air–sea CO 2 fluxes, the present configuration of Eco3M_MIX-CarbOx does not allow us to correctly reproduce the annual cycle of air–sea CO 2 fluxes observed in the area. This pattern directly impacts our estimates of the overall yearly air–sea CO 2 flux as, even if the model clearly identifies the bay as a CO 2 sink, its magnitude was underestimated, which may be an indication of the limitations inherent in dimensionless models for representing air–sea CO 2 fluxes. [ABSTRACT FROM AUTHOR]

The shape of nanochannels plays a crucial role in the ion selectivity and overall performance of reverse electrodialysis (RED) systems. However, current research on two-dimensional nanochannel shapes is largely limited to a few fixed asymmetric forms. This study explores the impact of randomly shaped nanochannels using dimensionless methods, controlling their randomness by varying their length and shape amplitude. The research systematically compares how alterations in the nanochannel length and shape amplitude influence various system performance parameters. Our findings indicate that increasing the nanochannel length can significantly enhance the system performance. While drastic changes in the nanochannel shape amplitude positively affect the system performance, the most significant improvements arise from the interplay between the nanochannel length and shape amplitude. This compounding effect creates a local optimum, resulting in peak system performance. Within the range of dimensionless lengths from 0 to 30, the system reaches its optimal performance at a dimensionless length of approximately 25. Additionally, we explored two other influencing factors: the nanochannel surface charge density and the concentration gradient of the solution across the nanochannel. Optimal performance is observed when the nanochannel has a high surface charge density and a low concentration gradient, particularly with random shapes. This study advances the theoretical understanding of RED systems in two-dimensional nanochannels, guiding research towards practical operational conditions. [ABSTRACT FROM AUTHOR]

Climate change is a global problem facing all aspects of the agricultural sector. Heat stress due to increasing atmospheric temperature is one of the most common climate change impacts on agriculture. Heat stress has direct effects on crop production, along with indirect effects through associated problems such as drought, salinity, and pathogenic stresses. Approaches reported to be effective to mitigate heat stress include nano-management. Nano-agrochemicals such as nanofertilizers and nanopesticides are emerging approaches that have shown promise against heat stress, particularly biogenic nano-sources. Nanomaterials are favorable for crop production due to their low toxicity and eco-friendly action. This review focuses on the different stresses associated with heat stress and their impacts on crop production. Nano-management of crops under heat stress, including the application of biogenic nanofertilizers and nanopesticides, are discussed. The potential and limitations of these biogenic nano-agrochemicals are reviewed. Potential nanotoxicity problems need more investigation at the local, national, and global levels, as well as additional studies into biogenic nano-agrochemicals and their effects on soil, plant, and microbial properties and processes. [ABSTRACT FROM AUTHOR]

Salinity is a very important parameter from an environmental perspective, and therefore, efficient and accurate systems are required for marine environmental monitoring and productive industries. A plasmonic sensor based on doubly deposited tapered optical fibers (DLUWTs—double-layer uniform-waist tapers) for the measurement of salinity is presented. The physical principle of the sensor, as well as its structure, is discussed, and its performance is experimentally demonstrated, obtaining very good sensitivities. The possibility of shifting towards higher wavelength measuring ranges associated with DLUWTs is also exploited. At the same time, we have considered the necessity of an extensive characterization of the behavior of the refractive index of salty water, both with variations in temperature and the composition of the salts dissolved. This is important due to the somehow changing reality of salinity measurements and the possibility of establishing new approaches for the determination of absolute salinity as opposed to practical salinity based on electrical conductivity measurements. The results obtained, which show high sensitivity and a good performance in general without the need for the use of semi-empirical algorithms, permit, in our opinion, an advance in the tendency towards refractometric determination of salinity with optical sensors apt for in situ, real-time, accurate measurements in realistic measuring conditions. [ABSTRACT FROM AUTHOR]

miRNA are endogenous regulatory molecules comprising 20–24 nucleotides playing a crucial role in the growth and development of various organs in animals as well as plants. In plants, miRNAs regulate biotic and abiotic stress responses conferring tolerance by functioning as negative and positive regulators. Down-regulation of the target genes is accomplished by repressing translation or by cleavage of a transcript or by inhibiting transcription. Various studies on crop plants like rice, wheat, and sugarcane have revealed the importance of miRNA in conferring abiotic stress tolerance against salinity and drought and biotic resistance against pests such as plant pathogens and insects. The biotic and abiotic stress regulates the target gene expression through the differential expression of specific miRNAs. An in-depth study of miRNA as a molecular marker in plants under stress conditions, profiling miRNA expressions and thorough understanding of its role in gene regulation may help in enhancing crop productivity and crop management against various stress conditions. So, the main objective of this review is to summarize recent advances in miRNA regulation in plants with special emphasis on its role in stress tolerance. [ABSTRACT FROM AUTHOR]

Many studies have examined the morphological and micromorphological responses of different halophytes to determine their salt tolerance mechanisms. However, few studies have focused on the South African edible halophytes. This study examined the leaf micromorphology, elemental composition, and anatomical responses using scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX) to examine salt tolerance levels in Trachyandra ciliata (L.F) Kunth. The treatments included varying sodium chloride (NaCl) concentrations: 50 mM, 100 mM, 150 mM and 200 mM, while control (0 mM) was watered with nutrient solution only. From the SEM micrographs, salt glands were observed protruding from the epidermis along the vascular system under low salinity and salt crystals appeared under higher concentrations, which makes this plant maintain cellular homeostasis under high salinity, and the plant can be classified as a recretohalophyte. Stomatal distribution, stomatal density and the number of open stomata decreased with increasing salinity. EDX revealed the presence of some important elements such as potassium, magnesium, phosphorus, calcium and more in the leaves. The results showed that increased salinity led to a decrease in the percentage composition of P, K and Ca2+, while Mg2+ was high under the control and low salinity (50 mM), decreased under 100 mM and increased again with increasing salinity. On the contrary, increasing salinity caused an increase in Na+ and Cl- in a stable manner. These findings reveal that T.ciliata acquires salt tolerance through changes to its leaf surface properties, osmotic adjustment, and the regulation of Na+ uptake and distribution in the leaves. [ABSTRACT FROM AUTHOR]

Spinach (Spinacia oleracea L.), a valuable crop, suffers greatly from salt stress. This study investigates the potential of green silver nanoparticles (Ag-NPs) synthesized using Aloe vera extract to relieve the harmful effects of salt stress on spinach seed germination and growth. The experiment evaluated various seed germination and plant growth characteristics of spinach cultivar Viroflay RZ under five Ag-NP concentrations (0, 20, 40, 80, and 100 ppm) and four salinity levels (0, 50, 100, and 150 mM NaCl) in a controlled laboratory setting. This studymeasured seed germination percentage, rate and relative germination, vigor indices, plant height, root length, shoot and root dry weight, and chlorophyll content. Data analysis revealed that salinity stress significantly inhibited seed germination and all other studied parameters, especially at higher salt concentrations. The impact of green Ag-NPs on these traits varied considerably under salt stress. A complex statistical model showed a non-linear relationship between Ag-NP concentration and its effect, with an optimal concentration potentially alleviating the negative effects of salt stress. The study suggests that pre-treating spinach seeds with green Ag-NPs at an optimized concentration might enhance their tolerance to salt stress, potentially improving germination and growth under saline conditions. This research promotes using eco-friendly nanotechnology to mitigate the detrimental effects of salinity on agricultural productivity. [ABSTRACT FROM AUTHOR]

Observations over a saltwater lagoon in the Altiplano show that evaporation E is triggered at noon, concurrent to the transition of a shallow, stable atmospheric boundary layer (ABL) into a deep mixed layer. We investigate the coupling between the ABL and E drivers using a land–atmosphere conceptual model, observations, and a regional model. Additionally, we analyze the ABL interaction with the aerodynamic and radiative components of evaporation using the Penman equation adapted to saltwater. Our results demonstrate that nonlocal processes are dominant in driving E. In the morning, the ABL is controlled by the local advection of warm air (∼5 K h−1), which results in a shallow (<350 m), stable ABL, with virtually no mixing and no E (<50 W m−2). The warm-air advection ultimately connects the ABL with the residual layer above, increasing the ABL height h by ∼1 km. At midday, a thermally driven regional flow arrives to the lagoon, which first advects a deeper ABL from the surrounding desert (∼1500 m h−1) that leads to an extra ∼700-m h increase. The regional flow also causes an increase in wind (∼12 m s−1) and an ABL collapse due to the entrance of cold air (∼−2 K h−1) with a shallower ABL (∼−350 m h−1). The turbulence produced by the wind decreases the aerodynamic resistance and mixes the water body releasing the energy previously stored in the lake. The ABL feedback on E through vapor pressure enables high evaporation values (∼450 W m−2 at 1430 LT). These results contribute to the understanding of E of water bodies in semiarid conditions and emphasize the importance of understanding ABL processes when describing evaporation drivers. [ABSTRACT FROM AUTHOR]

Biostimulants such as ascorbic acid, known as vitamin C, have been reported to have numerous positive roles in plant tolerance to abiotic stresses. However, little is known about the biostimulant effects of ascorbic acid on alfalfa (Medicago sativa). Accordingly, a pot experiment was conducted to investigate the effects of 1 mM ascorbic acid, applied as foliar spray, on the salt tolerance of a Moroccan alfalfa population Demnate 201. One month-old M. sativa seedlings were exposed to 200 mM NaCl for four weeks with or without 1 mM of exogenous ascorbic acid treatment. The results showed that salinity stress significantly (p < 0.001) reduced plant biomass, disturbed photosynthesis-related parameters and induced oxidative stress. However, ascorbic acid foliar spray counteracted the observed negative effects of salinity. It significantly (p < 0.001) improved plant growth and photosynthetic parameters. Besides, stress indicators, including Na+ in shoot and root, hydrogen peroxide and electrolyte leakage, were significantly reduced by 42%, 29%, 12% and 34%, respectively, in treated and salt-stressed alfalfa plants. Interestingly, the decrease in oxidative stress markers was positively correlated to the ability of ascorbic acid to induce the accumulation of flavonoids and to increase the antioxidant activity of guaiacol peroxidase. Furthermore, compatible solutes, such as proline and soluble sugars, were found higher especially in salt-stressed alfalfa plants treated with 1 mM ascorbic acid. Our findings showed that ascorbic acid supply could be an eco-friendly and sustainable technique to mitigate the toxic effect of salt and could improve alfalfa forage production when grown in salt-affected soils. [ABSTRACT FROM AUTHOR]

Wheat (Triticum aestivum L.) often faces salt stress and delayed sowing practices. These two events usually occur simultaneously in real field conditions that cause severe consequences on mineral balance, osmotic adjustment, reactive oxygen species (ROS) rampaging and antioxidant machinery. To address these issues, a two-year field-based study was directed at Jalalpur Pirwala Research Farm (JPRF), Multan-Pakistan. The experiment consisted of the following factors, a) timely sown under normal conditions (NS) and late sowing under normal conditions (LS) b) timely sown on saline conditions and late sown under saline conditions (LS+SS) c) foliar application of plant growth promoters hydrogen peroxide (H 2 O 2), salicylic acid (SA), thiourea (TU) and control (no spray) firstly to assess the influence of plant growth promoters (PGPRs) on the nutrient acquisition, osmoprotectants metabolism, ROS homeostasis and antioxidant clustering under SS, LS and their combined treatments. Results revealed that PGPRs foliar applications such as TU, followed by SA and H 2 O 2 played plausible roles in maintaining nutrient balance, osmoregulation, and circumventing the ROS. Exogenous application of TU increases the proline (18.24–20.01 %), total free amino acids (29.09 %-33.99 %), glycine betaine (3.43 %-15.34 %), total -soluble proteins (10.98 % -15.96 %) and total soluble sugars (15.21 %-20.36 %) for both years, under control conditions. Moreover, LS+SS followed by SS and LS declined the grain nutrient quality, shoot mineral content, and demolished the equilibrium between ROS and antioxidants, however, plants up-regulate the defensive mechanisms by enhancing the substantial content of antioxidants and osmoprotectants. So, wheat is moderately tolerant to combined LS+SS stress that evidently deteriorates its nutritional quality, but its performance can be enhanced by using PGPRs in delayed-sown wheat that often grows in marginally saline areas. [Display omitted] • Late-sown wheat faces severe nutrient imbalance under saline conditions. • Nutrient acquisition and, antioxidant metabolism play key role in wheat tolerance. • Plant growth promoters (PGPRs) improved the defence mechanisms and combat the effect of combined stress. • PGPRs maintain the nutrient balance and osmoregulation in late-sown wheat under salt stress. [ABSTRACT FROM AUTHOR]