Search Results (700)

Mycotoxins are the most frequently occurring natural contaminant in food and feed products. Through the deployment of diverse agricultural strategies or biological, chemical, or physical treatments of crop products, mycotoxin contamination remains a persistent issue for the agricultural sector and food/feed industry. We previously suggested that halophytes, thanks to their high antioxidant activity, could protect animal cell lines from mycotoxin contamination. Here, a hydroalcoholic extract of Calystegia soldanella L. leaves was evaluated for in vitro total antioxidant capacity (TAC) and 2,2-diphenyl-1-picrylhydrazyl (DPPH)-quenching bioassays, as well as anti-inflammatory (ELISA measurement of IL-8 secretion), ROS-inhibiting production (CellROX Green assay), and calcium influx restoration (fluorescent probe Fura2-QBT assay) activities in two animal cells upon mycotoxin intoxication. C. soldanella extract displayed high antioxidant activities (DPPH IC₅₀ < 80 μg·mL⁻¹ and TAC of 90 mg AAE·g⁻¹ DW. Moreover, it exhibited a significant protective action on renal (MDBK) and intestinal (IPEC-J2) cells against zearalenone (ZEA) or T2-toxin contamination, restoring about 75% of cell viability (MTS bioassay) at 1 μg·mL⁻¹. This effect was accompanied by strong anti-inflammatory, ROS-inhibition, and membrane integrity restoration activities. A bio-guided study revealed that the fraction of C. soldanella extract eluted from C18-bound silica with 60% methanol was the most active one. Upon HPLC and 1D- and 2D-NMR analyses, major compounds identified in this fraction were flavonol-type flavonoids, including quercetin-3-O-glucose (X1), quercetin-3-O-rutinoside (X2), and quercetin-3-O-glucose-6″-acetate (X3). Enriched sub-fractions containing these compounds largely contributed to the cytoprotective effects of C. soldanella, supporting its potential use as a food/feed ingredient. Full article

This study presents a multiproxy paleoecological reconstruction from Laguna El Cacahuate, located ~180 km inland in the floodplain of Tabasco, southeastern Mexico, where red mangrove (Rhizophora mangle L.) forms persistent forest stands under freshwater conditions. We analyzed a 180 cm sediment core using pollen analysis, X-ray fluorescence geochemistry, and radiocarbon dating to investigate the environmental drivers of inland mangrove expansion. The core spans the last ~5200 years, capturing major shifts in vegetation and hydroperiod change. During the mid-Holocene, herbaceous freshwater taxa (Poaceae, Cyperaceae) dominated the floodplain under variable hydroclimatic conditions and high clastic input. The appearance of Rhizophora mangle pollen around 750 cal yr BP marks a significant ecological transition coinciding with geochemical indicators of stabilized flooding and reduced sedimentation. This inland colonization aligns temporally with increased regional precipitation and possible hydrogeomorphic changes following the 13th-century Plinian eruption of El Chichón. Unlike coastal mangroves, the persistence of Rhizophora under freshwater conditions supports the interpretation of this species as a facultative halophyte and indicates high resilience to long-term hydrological shifts. These findings provide critical insight into the ecological plasticity of mangroves, the paleoenvironmental history of the lower Usumacinta–San Pedro Basin, and the importance of integrating long-term records for wetland conservation strategies under future climate scenarios. Full article

In a changing climate, sustainable agriculture urgently requires environmentally friendly solutions. Increasing soil salinity severely limits crop productivity, as excess salts induce osmotic and ion-specific toxicity in plants. A promising strategy for mitigating these effects and enhancing plant salt tolerance involves the use of biofertilizers based on plant growth-promoting (PGP) rhizobacteria. In this study, novel salt-tolerant PGP strains were isolated and characterized from the rhizosphere of the halophyte Atriplex prostrata grown in soils with varying salinity levels. Twelve isolates were screened for key PGP traits, including indole-3-acetic acid (IAA) production, phosphate solubilization, siderophore synthesis, and NaCl tolerance. Two strains, AP9 and AP12, demonstrated the most comprehensive PGP potential. Based on 16S rRNA gene sequencing, they were identified as members of the genus Serratia. In an experiment under salt stress (75, 150, and 225 mM NaCl), inoculation of wheat (Triticum aestivum L.) seeds with these strains significantly improved germination rates and stimulated root and shoot development. The treated plants also exhibited reduced levels of key oxidative stress markers—malondialdehyde (MDA) and proline. Thus, the Serratia sp. AP9 and AP12 strains exhibit pronounced PGP activity and efficacy in enhancing the salt tolerance of wheat. These results indicate that these isolates are promising candidates for the development of novel biofertilizers for sustainable agriculture on saline soils. Full article

Soil salinization poses a major constraint to global agriculture. Apocynum venetum, a salt-tolerant halophyte, provides an effective model for investigating salt-adaptive strategies; however, the temporal dynamics of its tolerance-associated genes and metabolites remain unclear. In this study, integrated transcriptomics, metabolomics (UHPLC-MS), physiological assays, and weighted gene co-expression network analysis (WGCNA) were conducted to characterize early (7-day) and late (18-day) responses to 200 mM NaCl stress. NaCl stress significantly reduced chlorophyll content while increasing Na⁺ accumulation, MDA levels, antioxidant enzyme activities (SOD and CAT), and total flavonoid content. Early responses (NaCl7) were marked by accumulation of ferulic acid, rhamnetin, and 3,4-dihydrocoumarin, with activation of plant hormone (ABA, auxin, zeatin) and MAPK signaling pathways. Late responses (NaCl18) exhibited increased accumulation of scopoletin, formononetin, and caffeyl-alcohol, with enrichment of phenylpropanoid biosynthesis, glutathione metabolism, and photosynthesis-related pathways. WGCNA identified early-response hub genes, including AOC, MAPKKK17/18, CYP98A, and CCoAOMT, coordinating stress signaling and antioxidant metabolism. Late stress responses involved genes like CPK, GST, CYCD3, and ARF, modulating calcium signaling and ROS detoxification. Genes shared across phases included CYP90C1, HD-ZIP, HSP20, and PP2C, regulating protein stabilization and stress signaling. These findings reveal a two-phase salt tolerance strategy in A. venetum, integrating early signaling and late metabolic adaptation. Full article

Several Fusarium species have demonstrated the ability to thrive in saline soils and to tolerate or prefer high salt concentrations. In this context, the potential halophilic or halotolerant lifestyle of Fusarium pseudograminearum was investigated. Four isolates (3B, PVS-Fu 7, ColPat-1, and CBS 109956) were grown at different temperatures (10, 15, 20, 25, 30, and 35 °C) and NaCl concentrations (0, 7, 14, 21, and 28 g L⁻¹), and daily growth, mycotoxin production, and K⁺ and Na⁺ accumulation within hyphae were assessed. All F. pseudograminearum isolates exhibited strong adaptability to saline conditions, with significantly enhanced growth in the presence of NaCl. All isolates accumulated Na⁺ within their hyphae while retaining K⁺. The production of deoxynivalenol (DON) and zearalenone (ZEA) was generally suppressed following NaCl exposure, consistent with the known inhibitory effect of reduced water activity on mycotoxin biosynthesis. However, at 22 °C, two isolates, 3B and CBS 109956, showed no significant differences in ZEA production between the control (no salt) and the medium containing the lowest NaCl concentration tested (7 g L⁻¹). Notably, isolate 3B, obtained from the halophyte Salicornia europaea, retained the highest levels of both Na⁺ and K⁺ within hyphae and showed the greatest overall adaptation to salinity. These results confirm the hypothesis that the ability of F. pseudograminearum to colonize and infect a halophytic host is indicative of a halophilic lifestyle. In the context of increasing soil salinization, these findings help identify conditions that permit pathogen persistence without hazardous mycotoxin accumulation. Full article

Limonium irtaense is an endangered halophyte endemic to coastal Castellón (Spain). This study aimed to support its conservation by assessing the effects of salinity on seed germination and seedling performance, as well as plants’ physiological and biochemical responses to salt stress during early vegetative growth. Seed germination was tested in the presence of 0 to 300 mM NaCl, followed by recovery assays for non-germinated seeds. Seedlings were grown under three salinity levels, by irrigation with water (control), 300 mM NaCl or 600 mM NaCl. Growth parameters, photosynthetic pigments, osmolytes, ion contents, oxidative stress markers and antioxidant compounds were determined in plants derived from the initial germination tests and the recovery of germination assays and subjected to the different salt treatments. Germination was highest in distilled water and declined with increasing salinity; however, salt-inhibited seeds germinated rapidly and efficiently in the recovery assays. Seedlings from salt-primed seeds showed higher survival rates and biomass than those from control germination tests. Salt treatments significantly reduced growth, with plants derived from salt-treated seeds generally showing higher tolerance, probably because of enhanced proline accumulation, more efficient transport and sequestration of toxic ions in leaf vacuoles, and potassium retention. These findings provide insights into L. irtaense adaptation mechanisms and support using salt-priming to improve conservation and translocation efforts for this endangered species. Full article

Low salinity tolerance during germination and early seedling establishment limits large-scale cultivation of halophytes for forage, food, restoration, and conservation purposes. This study evaluates the potential of redox priming to enhance salt tolerance in the perennial C₄ halophyte grass Urochondra setulosa, which could be used as a revegetation and phytoremediation crop for coastal saline lands. Fresh seeds were found to be non-dormant with ~90% mean final germination (MFG) in distilled water. Redox priming, including hydrogen peroxide (H₂O₂), melatonin (MT), sodium nitroprusside (SNP; a nitric oxide donor), and ascorbic acid (AsA), significantly accelerated the germination rate index (GRI) and reduced mean germination time (MGT) without altering MFG under non-saline conditions. Salinity severely suppressed germination, as unprimed seeds reached only ~1% MFG with ~99% germination reduction (GR) and near-zero germination stress tolerance index (GSTI) at 200 mM NaCl. All priming treatments significantly improved MFG, GRI, and GSTI and decreased GR, with H₂O₂ priming showing the highest amelioration. Ungerminated seeds from all treatments recovered ~90% germination capacity in water, indicating enforced dormancy owing to osmotic constraints. Salinity did not impair growth in unprimed seedlings. However, MT priming uniquely enhanced total length, leaf area, and seedling vigor index (SVI) at 200 mM NaCl, while MT and SNP priming resulted in the highest chlorophyll and carotenoid contents. Multivariate analyses confirmed MT’s consistent superiority across traits under stress. Thus, H₂O₂ priming optimizes germination, while MT priming improves seedling vigor and offers a practical, targeted strategy to improve early-stage salinity tolerance in U. setulosa for coastal revegetation and sustainable saline agriculture. Full article

The MYB transcription factor family plays crucial roles in plant growth, development, and responses to biotic and abiotic stresses. Seashore paspalum (Paspalum vaginatum) is a halophytic grass species with remarkable salt tolerance, yet its MYB gene family has not been systematically characterized. In this study, we conducted a genome-wide identification of MYB genes in seashore paspalum using a Hidden Markov Model (HMM)-based approach, resulting in the identification of 157 PvMYB genes. Phylogenetic and conserved motif analyses revealed distinct subfamily groupings and evolutionary relationships within the PvMYB family. Promoter analysis indicated that PvMYB genes contain multiple cis-acting elements responsive to light, hormones, and abiotic stresses, suggesting their potential regulatory roles under salt stress. Collinearity and duplication analyses demonstrated that gene duplication events contributed to the expansion of the PvMYB family. Moreover, protein interaction network prediction suggested that PvMYB73 may interact with key regulatory proteins such as BZIP8 and DREB1F involved in salt stress signaling. Transcriptome and reverse transcription quantitative PCR (RT-qPCR) analyses showed that PvMYB90, PvMYB123, and PvMYB150 were upregulated in leaves and roots under salinity stress, while PvMYB85 and PvMYB90 were experimentally validated to localize in the nucleus and function in salt tolerance regulation. Collectively, this study provides the first comprehensive characterization of the MYB gene family in seashore paspalum and offers valuable insights into the molecular mechanisms underlying salt tolerance in halophytic grasses. Full article

Salinity stress severely constrains plant growth and ecosystem functioning in arid and semi-arid regions, and plant growth-promoting rhizobacteria (PGPR) have been increasingly applied to enhance plant salt tolerance. Hoswever, it remains unclear whether different PGPR inoculation strategies confer salt resistance through similar or distinct physiological pathways, particularly in perennial halophytes adapted to saline environments. In this study, a field experiment was conducted to evaluate the effects of single- and multi-strain PGPR inoculation on the growth performance, physiological responses, and stress regulation of Atriplex canescens under saline conditions. Plant biomass allocation, photosynthetic traits, osmotic adjustment substances, antioxidant enzyme activities, and comprehensive stress tolerance indices were systematically assessed. The results showed that PGPR inoculation significantly improved plant growth and stress tolerance; however, the magnitude and underlying mechanisms varied across inoculation strategies. Single-strain inoculation predominantly enhanced root development and antioxidant regulation, whereas multi-strain inoculation tended to promote aboveground growth and photosynthetic performance. In contrast, certain strain combinations did not produce additive benefits, suggesting potential incompatibility among microbial consortia under salt stress. Multivariate analyses further indicated that improvements in stress tolerance were more closely associated with coordinated physiological regulation than with biomass accumulation alone. Overall, our findings demonstrate that PGPR-mediated salt tolerance in A. canescens is strategy-dependent and involves distinct resource allocation and stress-defense pathways. These results highlight the importance of considering inoculation strategies and functional compatibility when applying PGPR to improve plant performance in saline ecosystems. Full article

Bacterial communities in the rhizosphere and endorhizosphere of plants show distinct composition, function, and ecological roles during adaptation to diverse habitats. This study examines how rhizosphere and endophytic microbes associated with Aeluropus sinensis—a salt-excreting halophyte—contribute to its salt tolerance across saline-alkali environments. Microbial diversity and composition were analyzed via 16S rRNA gene amplicon sequencing. Soil physicochemical properties were measured to evaluate environmental effects. Linear regression assessed microbial–environment relationships, and co-occurrence networks identified key taxa and their adaptive strategies along environmental gradients. Soil salinity significantly affected rhizosphere bacterial diversity, with moderate levels increasing richness. Proteobacteria dominated both root and rhizosphere microbiomes across habitats. The endorhizosphere community strongly correlated with soil nutrients such as available phosphorus (AP) and total nitrogen (TN). Co-occurrence analysis reveals that chemoheterotrophic microbes in the A. sinensis rhizosphere employ distinct adaptive strategies across gradients, and ammonia-oxidizing bacteria (AOB) may support nitrogen cycling in the Yellow River Delta saline–alkaline ecosystem. This study underscores microbial adaptability in salt-tolerant grasses, demonstrating that comparing rhizosphere and endorhizosphere microbiomes in Poaceae under stress improves understanding of microbial functions in harsh environments. Full article

Functional properties of coastal halophytes are important for development of salt-tolerant cash crop cultures. The study of salt tolerance in coastal dune-building grass Leymus arenarius holds significant importance for its application in land reclamation, soil stabilization, and enhancing crop resilience to salinity stress. We used two accessions (LA1 and LA2) of L. arenarius to compare effects of salinity caused by NaCl and NaNO₃ on growth, ion accumulation and mineral nutrition in controlled conditions. L. arenarius plants exhibited high tolerance to sodium salts, with distinct effects on growth and development observed between chloride and nitrate treatments. While both salts negatively impacted root biomass, nitrate treatment (50–100 mmol L⁻¹) increased leaf number and biomass in LA2 plants, whereas chloride treatment decreased tiller and leaf sheath biomass. Despite individual variations, salinity treatments showed comparable effects on traits like tiller and leaf count, as well as leaf blade and sheath biomass. Salinity increased water content in leaf blades, sheaths, and roots, with LA2 plants showing the most pronounced effects. Chlorophyll a fluorescence measurements indicated a positive impact of NaNO₃ treatment on photosynthesis at intermediate salt concentrations, but a decrease at high salinity, particularly in LA2 plants. The accumulation capacity for Na⁺ in nitrate-treated plants reached 30 and 20 g kg⁻¹ in leaves and roots, respectively. In contrast, the accumulation capacity in chloride-treated plants was significantly lower, approximately 10 g kg⁻¹, in both leaves and roots. Both treatments increased nitrogen, phosphorus, and manganese concentrations in leaves and roots, with varying effects on calcium, magnesium, iron, zinc, and copper concentrations depending on the type of salt and tissue. These findings highlight the potential of L. arenarius for restoring saline and nitrogen-contaminated environments and position it as a valuable model for advancing research on salt tolerance mechanisms to improve cereal crop resilience. Full article

The nitrate signaling core regulator NLP7 is known to negatively regulate salt tolerance in Arabidopsis thaliana, but the function of the (SsNLP7A) gene in the halophyte Suaeda salsa remains unclear. To investigate whether SsNLP7A participates in salt stress responses, this study heterologously overexpressed the gene in tomato (Solanum lycopersicum) and systematically evaluated its function under salt stress through phenotypic, physiological, and transcriptomic analyses. The results indicate that SsNLP7A overexpression significantly promotes tomato root development and alleviates growth inhibition caused by salt stress. Under salt treatment, transgenic plants exhibited significantly higher chlorophyll content, accumulation of osmotic regulators (proline and soluble sugars), and antioxidant enzyme (POD, CAT, SOD) activity compared to wild-type plants. Transcriptome analysis further revealed that SsNLP7A enhances salt tolerance by regulating carbon metabolism, phytohormone signaling pathway, photosynthesis, and antioxidant pathways. Collectively, this study elucidates the positive regulatory role of SsNLP7A in salt stress response, providing new insights into its molecular mechanisms. Full article

Soil salinity is a major constraint on global crop production, disrupting photosynthesis, ion homeostasis, and growth. Beyond the roles of classic osmoprotectants and antioxidant enzymes, flavonoids have emerged as versatile mediators of salt stress tolerance at the interface of redox control, hormone signaling, and developmental plasticity. This review summarizes current evidence on how salinity remodels flavonoid biosynthesis, regulation, and function from cellular to whole-plant scales. We first outline the phenylpropanoid–flavonoid pathway, with emphasis on transcriptional control by MYB, bHLH, and NAC factors and their integration with ABA, JA, and auxin signaling. We then discussed how post-synthetic modifications such as glycosylation and methylation adjust flavonoid stability, compartmentation, and activity under salt stress. Functional sections highlight roles of flavonoids in ROS scavenging, Na⁺/K⁺ homeostasis, membrane integrity, and the modulation of ABA/MAPK/Ca²⁺ cascades and noncoding RNA networks. Spatial aspects, including root–shoot communication and rhizosphere microbiota recruitment, are also considered. Based on this synthesis, we propose a flavonoid-centered stress network (FCSN), in which specific flavonoids function as key nodes that connect metabolic flux with hormonal crosstalk and stress signaling pathways. We argue that reconceptualizing flavonoids as central stress network regulators, rather than generic antioxidants, provides a basis for metabolic engineering, bio-stimulant design, and breeding strategies aimed at improving crop performance on saline soils. Full article

Salicornia spp. is a halophytic plant with great potential in sustainable agriculture due to its ability to thrive in saline environments where conventional crops cannot grow. This study investigated Salicornia ramosissima J. Woods cultivated under two systems: hydroponics and substrate environments. The plants produced were subsequently preserved for food applications and chemically characterized within biorefinery processes. Analyses were performed using Fourier Transform Infrared Spectroscopy with Attenuated Total Reflection (FTIR-ATR), Ultraviolet/Visible Spectrophotometry, and Thin-Layer Chromatography (TLC). The hydroponic system proved to be the most promising cultivation method, promoting superior aerial growth ranging from 14% to 50% higher than substrate-grown plants throughout the cultivation period and achieving a higher biomass yield. Regarding pigment preservation, freezing best maintained compound integrity, as observed through TLC analysis, while desiccator and vacuum storage at room temperature were most suitable for hydroponically grown samples. Under vacuum storage, pigments pheophytin A and B and chlorophyll A showed an estimated 33% higher retention compared with desiccator storage. Both cultivation methods demonstrated potential for large-scale applications, highlighting Salicornia ramosissima J. Woods as a valuable crop for saline agriculture and sustainable food production. Full article

To clarify microbial assembly during saline–alkali wetland degradation, we analyzed bacterial (16S rRNA) and fungal (ITS) communities across four habitats: pristine wetland (PW), transitional meadow wetland (TMW), halophytic herbaceous community (HHC), and converted farmland (CF). Soil water content collapsed from PW (42.22%) to ≤18.40% elsewhere, and soils were alkaline with pH highest in HHC (10.08). Nutrient pools and enzyme activities were highest in PW (SOC 35.03 g kg⁻¹; URE 142.58 mg g⁻¹; SUC 527.83 mg g⁻¹) but declined sharply under natural degradation, reaching minima in HHC (SOC 8.02 g kg⁻¹). ACP and CAT were also lowest in HHC. Bacterial communities were dominated by Actinomycetota and Pseudomonadota, with Acidobacteriota and Bacillota enriched in CF. Bacterial diversity peaked in CF, whereas fungal richness was highest in CF and Shannon diversity peaked in TMW. Ordination and redundancy analyses indicated stronger edaphic control on bacteria than fungi, with pH, SOC, and moisture as key drivers. Null-model analyses showed bacterial assembly shifted toward deterministic selection under saline–alkali stress and agricultural conversion, whereas fungal assembly remained predominantly stochastic. Co-occurrence networks further suggested higher bacterial vulnerability under extreme degradation but comparatively higher fungal robustness. Overall, bacteria and fungi follow divergent assembly rules during saline–alkali wetland degradation. Full article