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Sesuvium portulacastrum floating treatment wetlands (FTWs) are effective at removing nitrogen and phosphorus, adsorbing heavy metals, and removing organic pollutants from aquaculture wastewater, and thus improve fish farming productivity. In this study, an S. portulacastrum FTW was used in a simulated grouper aquaculture experiment for 40 days. The FTW removed 1~3 mg/L of dissolved inorganic nitrogen (DIN) throughout the experimental period as well as the following toxic nitrogen species: 88% NO2−-N in the middle stage and 90% TAN (total ammonia nitrogen) in the middle stage. The health of the groupers was promoted and the weight of each grouper was 8% higher than those in the control group in the end. Compared with that of the control group, the carbon sequestration of the aquaculture ecosystem was also increased by S. portulacastrum FTW because more carbon was held in the biomass, including through the growth of the plant mass of the FTW, 109 g C/pond, and a reduction in fishing catch losses, 442 g C/pond. Therefore, S. portulacastrum FTW can serve as a potential technology for improving the water environment quality of feeding ponds and contributing to carbon sequestration in aquaculture systems. [ABSTRACT FROM AUTHOR]

Mariculture ponds are essential components of the coastal wetland, which are often criticized by eutrophication risk for the dissolved inorganic nitrogen (DIN) input to the coastal zone by the culture tailwater. However, the reduce of this DIN pollution was difficult because the tailwater is hard to collect and the treatment is inefficient and expensive. Sesuvium Portulacastrum is a coastal vegetation which has high efficiency in DIN absorption from the seawater and sediment. In this study, we use Sesuvium Portulacastrum as a tool species to study the control behavior of the DIN in mariculture ponds wetland. The change trend of DIN in pond water and benthic species in pond sediment was investigated. The results showed that Sesuvium Portulacastrum reduced NH4+, NO3-, and NO2- in the pond water by 83.21%, 95.22%, and 91.32%, respectively. The species number of benthic organisms was enhanced from 2 to 5 and the species structure was more optimized in Sesuvium Portulacastrum pond than control pond. At the end of the experiment, eutrophication indicator species (Capitella capitata) was disappeared in the Sesuvium Portulacastrum pond. Those suggest that the coastal vegetation (Sesuvium Portulacastrum) have great potential to eliminate DIN pollutants in mariculture pond wetland. [ABSTRACT FROM AUTHOR]

The objective of the present study was to isolate endophytes from the roots of the halophyte Sesuvium portulacastrum, which is applied for aquatic phytoremediation. From these endophytes, siderophore-producing bacteria were specifically isolated for their potential capacity to promote plant growth. The siderophore production capacity of the isolated bacteria was quantified, and a high-yield siderophore-producing strain was selected for further investigation. A total of 33 endophytic bacteria were successfully isolated and identified using a culturable approach. Of these, 10 siderophore-producing bacteria were identified using the selective agar assay, displaying siderophore unit (SU) values ranging from 11.90% to 80.39%. It is noteworthy that Erwinia sp. QZ-E9 exhibited the highest siderophore production capacity, achieving an SU of 80.39%. A microcosm co-cultivation experiment was conducted with the strain QZ-E9 in iron-deficient conditions (2 μmol/L Fe3⁺). The results demonstrated that strain QZ-E9 significantly enhanced the growth of S. portulacastrum, by increases in both fresh weight (1.41 g) and root length (18.7 cm). Furthermore, fluorescence in situ hybridization (FISH) was utilized to ascertain the colonization pattern of strain QZ-E9 within the plant roots. The analysis demonstrated that strain QZ-E9 exhibited extensive colonization of the epidermal and outer cortical cells of S. portulacastrum roots, as well as the intercellular spaces and vascular tissues. This colonization indicated that Erwinia sp. QZ-E9 plays a crucial role in promoting the growth of S. portulacastrum, presumably through its siderophore-mediated iron acquisition mechanism. [ABSTRACT FROM AUTHOR]

Sesuvium portulacastrum L. is a flowering succulent halophyte in the ice plant family Aizoaceae. There are various ecotypes distributed in sandy coastlines and salty marshlands in tropical and subtropical regions with the common name of sea purslane. These plants are tolerant to salt, drought, and flooding stresses and have been used for the stabilization of sand dunes and the restoration of coastal areas. With the increased salinization of agricultural soils and the widespread pollution of toxic metals in the environment, as well as excessive nutrients in waterbodies, S. portulacastrum has been explored for the desalination of saline soils and the phytoremediation of metals from contaminated soils and nitrogen and phosphorus from eutrophic water. In addition, sea purslane has nutraceutical and pharmaceutical value. Tissue analysis indicates that many ecotypes are rich in carbohydrates, proteins, vitamins, and mineral nutrients. Native Americans in Florida eat it raw, pickled, or cooked. In the Philippines, it is known as atchara after being pickled. S. portulacastrum contains high levels of ecdysteroids, which possess antidiabetic, anticancer, and anti-inflammatory activities in mammals. In this review article, we present the botanical information, the physiological and molecular mechanisms underlying the tolerance of sea purslane to different stresses, its nutritional and pharmaceutical value, and the methods for its propagation and production in saline soils and waterbodies. Its adaptability to a wide range of stressful environments and its role in the production of valuable bioactive compounds suggest that S. portulacastrum can be produced in saline soils as a leafy vegetable and is a valuable genetic resource that can be used for the bioremediation of soil salinity and eutrophic water. [ABSTRACT FROM AUTHOR]

Sesuvium portulacastrum, a coastal medicinal plant with traditional uses has shown promising biological activities including anti-inflammatory, antioxidant and antimicrobial properties. However, the mechanisms of action active ingredients of this plant have not been studied. Aim of the current study is to investigate the anticancer activity of Sesuvium portulacastrum using in vitro and in silico analysis. The in vitro assays included NO radical scavenging activity, total phenolic and flavonoid content determination. The data were analysed by one-way-ANOVA and p

Abstract Background The Aizoaceae family’s Sesuvium sesuvioides (Fenzl) Verdc is a medicinal species of the Cholistan desert, Pakistan. The purpose of this study was to determine the genomic features and phylogenetic position of the Sesuvium genus in the Aizoaceae family. We used the Illumina HiSeq2500 and paired-end sequencing to publish the complete chloroplast sequence of S. sesuvioides. Results The 155,849 bp length cp genome sequence of S. sesuvioides has a 36.8% GC content. The Leucine codon has the greatest codon use (10.6%), 81 simple sequence repetitions of 19 kinds, and 79 oligonucleotide repeats. We investigated the phylogeny of the order Caryophyllales’ 27 species from 23 families and 25 distinct genera. The maximum likelihood tree indicated Sesuvium as a monophyletic genus, and sister to Tetragonia. A comparison of S. sesuvioides, with Sesuvium portulacastrum, Mesembryanthemum crystallinum, Mesembryanthemum cordifolium, and Tetragonia tetragonoides was performed using the NCBI platform. In the comparative investigation of genomes, all five genera revealed comparable cp genome structure, gene number and composition. All five species lacked the rps15 gene and the rpl2 intron. In most comparisons with S. sesuvioides, transition substitutions (Ts) were more frequent than transversion substitutions (Tv), producing Ts/Tv ratios larger than one, and the Ka/Ks ratio was lower than one. We determined ten highly polymorphic regions, comprising rpl22, rpl32-trnL-UAG, trnD-GUC-trnY-GUA, trnE-UUC-trnT-GGU, trnK-UUU-rps16, trnM-CAU-atpE, trnH-GUG-psbA, psaJ-rpl33, rps4-trnT-UGU, and trnF-GAA-ndhJ. Conclusion The whole S. sesuvioides chloroplast will be examined as a resource for in-depth taxonomic research of the genus when more Sesuvium and Aizoaceae species are sequenced in the future. The chloroplast genomes of the Aizoaceae family are well preserved, with little alterations, indicating the family’s monophyletic origin. This study’s highly polymorphic regions could be utilized to build realistic and low-cost molecular markers for resolving taxonomic discrepancies, new species identification, and finding evolutionary links among Aizoaceae species. To properly comprehend the evolution of the Aizoaceae family, further species need to be sequenced.

The objective of the present study was to isolate endophytes from the roots of the halophyte Sesuvium portulacastrum, which is applied for aquatic phytoremediation. From these endophytes, siderophore-producing bacteria were specifically isolated for their potential capacity to promote plant growth. The siderophore production capacity of the isolated bacteria was quantified, and a high-yield siderophore-producing strain was selected for further investigation. A total of 33 endophytic bacteria were successfully isolated and identified using a culturable approach. Of these, 10 siderophore-producing bacteria were identified using the selective agar assay, displaying siderophore unit (SU) values ranging from 11.90% to 80.39%. It is noteworthy that Erwinia sp. QZ-E9 exhibited the highest siderophore production capacity, achieving an SU of 80.39%. A microcosm co-cultivation experiment was conducted with the strain QZ-E9 in iron-deficient conditions (2 μmol/L Fe3⁺). The results demonstrated that strain QZ-E9 significantly enhanced the growth of S. portulacastrum, by increases in both fresh weight (1.41 g) and root length (18.7 cm). Furthermore, fluorescence in situ hybridization (FISH) was utilized to ascertain the colonization pattern of strain QZ-E9 within the plant roots. The analysis demonstrated that strain QZ-E9 exhibited extensive colonization of the epidermal and outer cortical cells of S. portulacastrum roots, as well as the intercellular spaces and vascular tissues. This colonization indicated that Erwinia sp. QZ-E9 plays a crucial role in promoting the growth of S. portulacastrum, presumably through its siderophore-mediated iron acquisition mechanism.

【Objective】Sesuvium portulacastrum, a typical coastal and mangrove associate plant, is capable of retaining sand and protecting banks. It can grow normally in seawater and has a strong salt tolerance. Na+/H+ exchange (NHX) plays a key role in salt tolerance and plant growth with development. In order to understand the role of NHX in salt tolerance of S. portulacastrum, the NHX genes were identified and analyzed.【Method】In this study, the S. portulacastrum NHX genes were identified by using informatic method through its full length transcriptome data. Their physicochemical properties, conserved motifs and evolutionary relationships were analyzed, and the expression patterns of NHX genes under s alt stress were studied by quantative real-time PCR (qRT-PCR).【Result】The results showed that 12 SpNHX genes were identified from S. portulacastrum and named as SpNHX1 to SpNHX12. The number of amino acids ranged from 276 to 554, with the molecular weight ranged from 31.22 to 61.21 kD, isoelectric point from 5.55 to 8.64, and instability ind ex from 32.14 to 50.54. All the proteins were hydrophobic. Phylogenetic analysis showed that SpNHX proteins can be divided into two subgroups. Similar conserved motifs composition was found in each subgroup. Multiple sequence alignment results showed that all SpNHX proteins had Na+/H+ exchange conserved domains. RNA-seq data and qRT-PCR results showed that SpNHX genes were induced to different degrees under salt stress, and SpNHX1, SpNHX9, SpNHX10, SpNHX11 and SpNHX12 were significantly up-regulated under salt stress.【Conclusion】This study clarified the expression patterns of NHXs in S. portulacastrum under high salt stress, indicating that SpNHX1, SpNHX9, SpNHX10, SpNHX11 and SpNHX12 may be involved in the response of S. portulacastrum to salt stress, which provided a theoretical basis for further research on the role of NHX in the process of salt tolerance of S. portulacastrum.

Background: The Aizoaceae family's Sesuvium sesuvioides (Fenzl) Verdc is a medicinal species of the Cholistan desert, Pakistan. The purpose of this study was to determine the genomic features and phylogenetic position of the Sesuvium genus in the Aizoaceae family. We used the Illumina HiSeq2500 and paired-end sequencing to publish the complete chloroplast sequence of S. sesuvioides. Results: The 155,849 bp length cp genome sequence of S. sesuvioides has a 36.8% GC content. The Leucine codon has the greatest codon use (10.6%), 81 simple sequence repetitions of 19 kinds, and 79 oligonucleotide repeats. We investigated the phylogeny of the order Caryophyllales' 27 species from 23 families and 25 distinct genera. The maximum likelihood tree indicated Sesuvium as a monophyletic genus, and sister to Tetragonia. A comparison of S. sesuvioides, with Sesuvium portulacastrum, Mesembryanthemum crystallinum, Mesembryanthemum cordifolium, and Tetragonia tetragonoides was performed using the NCBI platform. In the comparative investigation of genomes, all five genera revealed comparable cp genome structure, gene number and composition. All five species lacked the rps15 gene and the rpl2 intron. In most comparisons with S. sesuvioides, transition substitutions (Ts) were more frequent than transversion substitutions (Tv), producing Ts/Tv ratios larger than one, and the Ka/Ks ratio was lower than one. We determined ten highly polymorphic regions, comprising rpl22, rpl32-trnL-UAG, trnD-GUC-trnY-GUA, trnE-UUC-trnT-GGU, trnK-UUU-rps16, trnM-CAU-atpE, trnH-GUG-psbA, psaJ-rpl33, rps4-trnT-UGU, and trnF-GAA-ndhJ. Conclusion: The whole S. sesuvioides chloroplast will be examined as a resource for in-depth taxonomic research of the genus when more Sesuvium and Aizoaceae species are sequenced in the future. The chloroplast genomes of the Aizoaceae family are well preserved, with little alterations, indicating the family's monophyletic origin. This study's highly polymorphic regions could be utilized to build realistic and low-cost molecular markers for resolving taxonomic discrepancies, new species identification, and finding evolutionary links among Aizoaceae species. To properly comprehend the evolution of the Aizoaceae family, further species need to be sequenced. [ABSTRACT FROM AUTHOR]

Introduction: Salt stress is a major constraint affecting crop productivity worldwide. Investigation of halophytes could provide valuable information for improving economically important crops to tolerate salt stress and for more effectively using halophytes to remediate saline environments. Sesuvium portulacastrum L. is a halophyte species widely distributed in tropical and subtropical coastal regions and can absorb a large amount of sodium (Na). This study was to analyze S. portulacastrum responses to salt stress at morphological, physiological, proteomic, and metabolomic levels and pursue a better understanding of mechanisms behind its salt tolerance. Methods: The initial experiment evaluated morphological responses of S. portulacastrum to different concentrations of NaCl in a hydroponic system, and subsequent experiments compared physiological, proteomic, and metabolomic changes in S. portulacastrum after being exposed to 0.4 M NaCl for 24 h as immediate salt stress (IS) to 14 days as adaptive salt stress (AS). Through these analyses, a working model to illustrate the integrative responses of S. portulacastrum to salt stress was proposed. Results: Plants grown in 0.4 M NaCl were morphologically comparable to those grown in the control treatment. Physiological changes varied in control, IS, and AS plants based on the measured parameters. Proteomic analysis identified a total of 47 and 248 differentially expressed proteins (DEPs) in leaves and roots, respectively. KEGG analysis showed that DEPs, especially those occurring in roots, were largely related to metabolic pathways. Root metabolomic analysis showed that 292 differentially expressed metabolites (DEMs) occurred in IS plants and 371 in AS plants. Among them, 20.63% of upregulated DEMs were related to phenolic acid metabolism. Discussion: Based on the integrative analysis of proteomics and metabolomics, signal transduction and phenolic acid metabolism appeared to be crucial for S.portulacastrum to tolerate salt stress. Specifically, Ca2+, ABA, and JA signalings coordinately regulated salt tolerance in S. portulacastrum. The stress initially activated phenylpropanoid biosynthesis pathway through Ca2+ signal transduction and increased the content of metabolites, such as coniferin. Meanwhile, the stress inhibited MAPK signaling pathway through ABA and JA signal transduction, which promoted Na sequestration into the vacuole to maintain ROS homeostasis and enhanced S. portulacastrum tolerance to salt stress. [ABSTRACT FROM AUTHOR]

Background: Sesuvium portulacastrum is a facultative halophyte capable of thriving in a saline environment. Despite molecular studies conducted to unravel its salt adaptation mechanism, there is a paucity of information on the role of salt-responsive orthologs and microRNAs (miRNAs) in this halophyte. Here, we searched the orthology to identify salt-responsive orthologs and miRNA targets of Sesuvium using the Arabidopsis genome. Methods: The relative fold change of orthologs, conserved miRNAs, and miRNA targets of Sesuvium was analyzed under 100 mM (LS) and 250 mM NaCl (HS) treatment at 24 h using qRT-PCR. The comparison between the expression of Sesuvium orthologs and Arabidopsis orthologs (Arabidopsis eFP browser database) was used to identify differentially expressed genes. Results: Upon salt treatment, we found that SpCIPK3 (1.95-fold in LS and 2.90-fold in HS) in Sesuvium roots, and SpNHX7 (1.61-fold in LS and 6.39-fold in HS) and, SpSTPK2 (2.54-fold in LS and 7.65-fold in HS) in Sesuvium leaves were upregulated in a salt concentration-specific manner. In Arabidopsis, these genes were either downregulated or did not show significant variation, implicating its significance in the halophytic nature of Sesuvium. Furthermore, miRNAs like miR394a, miR396a, and miR397a exhibited a negative correlation with their targets—Frigida interacting protein 1, Cysteine proteinases superfamily protein, and Putative laccase, respectively under different salt treatments. Conclusion: The study revealed that the high salt tolerance in Sesuvium is associated with distinct transcriptional reprogramming, hence, to gain holistic mechanistic insights, global-scale profiling is required. [ABSTRACT FROM AUTHOR]

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We conducted a study to examine the growth and physiological changes in 12 different ecotypes of Sesuvium portulacastrum collected from Hainan Island in China. These ecotypes were subjected to different concentrations (0, 200, 400, and 600 mmol/L) of sodium chloride (NaCl) salt stress for 14 days. We also analyzed the expression of metabolic genes related to stress response. Under low salt stress, indicators such as plant height in region K (0 mmol/L: 45% and highest at 200 mmol/L: 80%), internode length (0 mmol/L: 0.38, 200 mmol/L: 0.87, 400 mmol/L: 0.25, and 600 mmol/L: 1.35), as well as leaf area, relative water content, fresh weight, and dry weight exhibited an overall increasing trend with the increase in salt concentration. However, as the salt concentration increased, these indicators showed a decreasing trend. Proline and malondialdehyde contents increased with higher salt concentrations. When the NaCl concentration was 400 mmol/L, MDA content in the leaves was highest in the regions E (196.23%), F (94.28%), J (170.10%), and K (136.08%) as compared to the control group, respectively. Most materials demonstrated a significant decrease in chlorophyll a, chlorophyll b, and total chlorophyll content compared to the control group. Furthermore, the ratio of chlorophyll a to chlorophyll b (Rab) varied among different materials. Using principal component analysis, we identified three ecotypes (L from Xinglong Village, Danzhou City; B from Shuigoupo Village, Lingshui County; and J from Haidongfang Park, Dongfang City) that represented high, medium, and low salt tolerance levels, respectively, based on the above growth and physiological indexes. To further investigate the expression changes of related genes at the transcriptional level, we employed qRT-PCR. The results showed that the relative expression of SpP5CS1, SpLOX1, and SpLOX1 genes increased with higher salt concentrations, which corresponded to the accumulation of proline and malondialdehyde content, respectively. However, the relative expression of SpCHL1a and SpCHL1b did not exhibit a consistent pattern. This study contributes to our understanding of the salt tolerance mechanism in the true halophyte S. portulacastrum, providing a solid theoretical foundation for further research in this field. [ABSTRACT FROM AUTHOR]

Growth and development of plants are greatly affected by salinity. The salt overly sensitive (SOS) pathway plays a vital role in plants responding to salt stress, and has been reported to contain three components: SOS3 (calcineurin B-like protein 4, CBL4), SOS2 (CBL-interacting protein kinase 24, CIPK24) and SOS1. Our previous study demonstrated that transgenic yeast and Arabidopsis could tolerate salt better when expressed with the cell membrane Na+/H+ antiporter SOS1 from the halophyte Sesuvium portulacastrum. Here, a new CIPK gene (SpCIPK8) and CBL gene (SpCBL10) have been isolated from S. portulacastrum. The expression of SpCIPK8 and SpCBL10 was induced by salinity in roots of S. portulacastrum. An interaction between SpCBL10 and SpCIPK8 was demonstrated in yeast two-hybrid assays. Subsequent analysis found that SpCBL10 could bind the C-terminus of SpCIPK8. Yeast co-expressing SpSOS1, SpCIPK8 and SpCBL10 genes grew better and accumulated more potassium (K+) and less sodium (Na+) under salt stress than yeast that expressed only one or two of these genes, indicating that Na+ was excluded from the cells. Furthermore, we found that the SpCBL10/SpCIPK8 complex regulates the cell membrane Na+/H+ antiporter SpSOS1 to enhance yeast salt tolerance by binding the two serine residues at amino acid positions 1144 and 1146 in the conserved DSPS motif at the C-terminus of SpSOS1. Future studies of the SOS pathway will be greatly aided by these results, which suggest some candidate genes for improving plant salt tolerance. [ABSTRACT FROM AUTHOR]

The study reported the effect of contamination of Sesuvium portulacastrum L. after exposure to Ag and Pb for four weeks. The results showed that the total protein, chlorophyll, carotene, and biomass declined gradually by elevating the heavy metal concentrations. Elemental analyses of the leaves were performed using scanning electron microscopy with energy–dispersive- X-ray spectroscopy (SEM-EDS). The main mineral of control treatment contained 11 elements including carbon (57.50%) followed by oxygen (22.76%) and trace iron and lead. The minerals in the leaves treated with 100 mg L-1 Pb exhibited 12 elements with high levels of lead (52.03%). The leaves treated with 100 mg L-1 Ag showed 11 elements with high levels of silver (43.02%) followed by carbon (34.95%) and oxygen (11.18%). Anatomical study indicated that the Ag and Pb can accumulate in internal tissues and causes several alterations such as shape of leaves, stems and roots, as well as thickness and number of cortical parenchymal cells. In addition, unrecognized the endodermis, and exodermis, the root thickness was 663.21 µm in control group, while in Ag and Pb treatments were 498.32 µm and 375.61 µm respectively.

Background: Leafy vegetables play an important role by contributing to most nutrients intake for health and human well‐being. Some of these leafy vegetables are cooked before consumption. But the effect of the cooking process on the nutritional value of leafy vegetables is not well known. This research aimed to evaluate the effect of the cooking process on the nutritional value of Sesuvium portulacastrum leaves. To do that, fresh leaves were collected, air dried and divided into raw and cooked. The raw and cooked samples were analyzed to determine the physico‐chemical properties (pH, humidity, ash, polyphenols, tannins and proteins) and minerals (nitrogen, calcium, magnesium, sodium and potassium). Results: Based on physico‐chemicals, the raw and cooked leaves contained a good concentration of polyphenol (155.58 mg ± 14.98 and 53.45 mg ± 10.97), tannin (107.62 mg ± 9.8 and 59.59 mg ± 4.17), nitrogen (0.41% ± 0.02 and 0.38% ± 0.02) and protein (2.59% ± 0.12 and 2.38% ± 0.14). The cooking process caused the loss of nitrogen (N), proteins, tannins and polyphenols from 8% to 66%. S. portulacastrum leaves contented also an important proportion of minerals. The raw and cooked contained sodium (30% and 21.28%), potassium (30% and 13.08%), magnesium (16.71% and 19.9%) and calcium (6.5% and 24%). The cooking process increased and reduced significantly calcium (270.42%) and potassium (56.42%), respectively. Conclusion: S. portulacastrum leaves were an important source of nutritional value that could contribute to improved health and well‐being. [ABSTRACT FROM AUTHOR]

Sesuvium portulacastrum has a strong salt tolerance and can grow in saline and alkaline coastal and inland habitats. This study investigated the physiological and molecular responses of S. portulacastrum to high salinity by analyzing the changes in plant phytohormones and antioxidant activity, including their differentially expressed genes (DEGs) under similar high-salinity conditions. High salinity significantly affected proline (Pro) and hydrogen peroxide (H2O2) in S. portulacastrum seedlings, increasing Pro and H2O2 contents by 290.56 and 83.36%, respectively, compared to the control. Antioxidant activities, including superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT), significantly increased by 83.05, 205.14, and 751.87%, respectively, under high salinity. Meanwhile, abscisic acid (ABA) and gibberellic acid (GA3) contents showed the reverse trend of high salt treatment. De novo transcriptome analysis showed that 36,676 unigenes were matched, and 3,622 salt stress-induced DEGs were identified as being associated with the metabolic and biological regulation processes of antioxidant activity and plant phytohormones. POD and SOD were upregulated under high-salinity conditions. In addition, the transcription levels of genes involved in auxin (SAURs and GH3), ethylene (ERF1, ERF3, ERF114, and ABR1), ABA (PP2C), and GA3 (PIF3) transport or signaling were altered. This study identified key metabolic and biological processes and putative genes involved in the high salt tolerance of S. portulacastrum and it is of great significance for identifying new salt-tolerant genes to promote ecological restoration of the coastal strand. [ABSTRACT FROM AUTHOR]

Soil salinity is an important environmental problem that seriously affects plant growth and crop productivity. Phytoremediation is a cost-effective solution for reducing soil salinity and potentially converting the soils for crop production. Sesuvium portulacastrum is a typical halophyte which can grow at high salt concentrations. In order to explore the salt tolerance mechanism of S. portulacastrum, rooted cuttings were grown in a hydroponic culture containing 1/2 Hoagland solution with or without addition of 400 mM Na for 21 days. Root and leaf samples were taken 1 h and 21 days after Na treatment, and RNA-Seq was used to analyze transcript differences in roots and leaves of the Na-treated and control plants. A large number of differentially expressed genes (DEGs) were identified in the roots and leaves of plants grown under salt stress. Several key pathways related to salt tolerance were identified through KEGG analysis. Combined with physiological data and expression analysis, it appeared that cyclic nucleotide gated channels (CNGCs) were implicated in Na uptake and Na+/H+ exchangers (NHXs) were responsible for the extrusion and sequestration of Na, which facilitated a balance between Na+ and K+ in S. portulacastrum under salt stress. Soluble sugar and proline were identified as important osmoprotectant in salt-stressed S. portulacastrum plants. Glutathione metabolism played an important role in scavenging reactive oxygen species. Results from this study show that S. portulacastrum as a halophytic species possesses a suite of mechanisms for accumulating and tolerating a high level of Na; thus, it could be a valuable plant species used for phytoremediation of saline soils. [ABSTRACT FROM AUTHOR]

The study reported the effect of contamination of Sesuvium portulacastrum L. after exposure to Ag and Pb for four weeks. The results showed that the total protein, chlorophyll, carotene, and biomass declined gradually by elevating the heavy metal concentrations. Elemental analyses of the leaves were performed using scanning electron microscopy with energy--dispersive- X-ray spectroscopy (SEM-EDS). The main mineral of control treatment contained 11 elements including carbon (57.50%) followed by oxygen (22.76%) and trace iron and lead. The minerals in the leaves treated with 100 mg L-1 Pb exhibited 12 elements with high levels of lead (52.03%). The leaves treated with 100 mg L-1 Ag showed 11 elements with high levels of silver (43.02%) followed by carbon (34.95%) and oxygen (11.18%). Anatomical study indicated that the Ag and Pb can accumulate in internal tissues and causes several alterations such as shape of leaves, stems and roots, as well as thickness and number of cortical parenchymal cells. In addition, unrecognized the endodermis, and exodermis, the root thickness was 663.21 µm in control group, while in Ag and Pb treatments were 498.32 µm and 375.61 µm respectively. [ABSTRACT FROM AUTHOR]

Mangroves are trees or large shrubs which have special adaptations to survive in this environment and grow within the intertidal zone in tropical and subtropical regions. Sesuvium portulacastrum (seapurslane) is, herbaceous, perennial, dichotomous, halophyte fast growing plant that belongs to family Aizoaceae. Salicornia brachiata Roxb, is a halophyte, commonly known as sea asparagus widely used as food item in several countries. Then, In vitro studies like, antioxidant, anti-inflammatory and antimycobacterial assay was carried out. The IC50 values of Salicornia brachiata and Sesuvium portulacastru was found to be 288.166, 369.451 and 369.764 µg/ml for DPPH scavenging activity. The presence of various primary and secondary metabolites was revealed in the present study. It also showed the better in vitro activities and was the most active plants against MDRTB, MTB and H37RV strain. This study validates the medicinal use of plants in the treatment of TB which have promising effect against MDRTB, MTB and H37RV. [ABSTRACT FROM AUTHOR]

Sesuvium portulacastrum is a true halophyte and shows an optimal development under moderate salinity with large amounts of salt ions in its leaves. However, the specific proteins in response to salt ions are remained unknown. In this study, comparative physiological and proteomic analyses of different leaves subject to NaCl, KCl, NaNO 3 and KNO 3 were performed. Chlorophyll content was decreased under the above four kinds of salt treatments. Starch and soluble sugar contents changed differently under different salt treatments. A total of 53 differentially accumulated proteins (DAPs) were identified by mass spectrometry. Among them, 13, 25, 26 and 25 DAPs were identified after exposure to KCl, NaCl, KNO 3, and NaNO 3 , respectively. These DAPs belong to 47 unique genes, and 37 of them are involved in protein-protein interactions. These DAPs displayed different expression patterns after treating with different salt ions. Functional annotation revealed they are mainly involved in photosynthesis, carbohydrate and energy metabolism, lipid metabolism, and biosynthesis of secondary metabolites. Genes and proteins showed different expression profiles under different salt treatments. Enzyme activity analysis indicated P-ATPase was induced by KCl, NaCl and NaNO 3 , V-ATPase was induced by KCl and NaCl, whereas V-PPase activity was significantly increased after application of KNO 3 , but sharply inhibited by NaCl. These results might deepen our understanding of responsive mechanisms in the leaves of S. portulacastrum upon different salt ions. [Display omitted] • Proteomics of Sesuvium portulacastrum leaves subjected to NaCl, KCl, NaNO 3 and KNO 3 were performed. • A total of 53 differentially accumulated proteins (DAPs) upon different salt ions were identified by mass spectrometry. • Genes and proteins showed different expression profiles under different salt treatments in S. portulacastrum leaves. • Activities of P-ATPase and V-PPase were induced by KCl and NaCl, but V-PPase activity was significantly increased upon KNO 3. • Proteins in S. Portulacastrum leaves are more sensitive to Na + than K+ and Cl−. [ABSTRACT FROM AUTHOR]

Questions: Does the presence of salt marsh vegetation affect the long‐term regeneration of the pioneer mangrove species Avicennia germinans in a degraded dwarf forest? Does immobilized coarse woody debris (CWD) affect regeneration similarly? Do larger trees suppress or facilitate intraspecific saplings? Location: Dwarf mangrove forest in the high intertidal zone on the Bragança peninsula in northern Brazil. Methods: The spatial patterns of A. germinans, the herbaceous halophyte Sesuvium portulacastrum, and CWD were mapped in three sample plots (each 400 m2) during two consecutive vegetation surveys, conducted in 2011 and 2014. Inhomogeneous Poisson and Thomas point process models were used to assess the distribution of A. germinans life‐history stages (seedlings, saplings, and adult dwarf trees), conditioned on the presence of S. portulacastrum and CWD. In addition, intraspecific interactions between trees and regeneration were assessed based on crown projection mapping. Bivariate point pattern analyses were used to assess the dependence of advance regeneration on dwarf A. germinans trees and S. portulacastrum. Results: Avicennia germinans saplings and trees were positively associated with S. portulacastrum and CWD, whereas seedlings were located around tree crowns. The density of fruit‐bearing trees was positively associated with sapling density, indicating that regeneration relied on locally dispersed propagules. Conclusions: Herbaceous vegetation and CWD have an important ecological function in degraded mangroves by retaining tidally dispersed propagules. Here, we show that herbaceous vegetation does not suppress the growth of seedlings but facilitates mangrove recolonization. Due to limited tidal dispersal, regeneration relies on local propagule supply. In addition to hydrological restoration, the observed vegetation patterns suggest that, in the absence of propagule‐retaining vegetation, restoration of high‐intertidal mangroves can be facilitated by establishing nuclei of planted trees and installing secured logs. [ABSTRACT FROM AUTHOR]

Psammophilic halophytes are subjected in their natural habitats to the interactive effects of salinity and nutrient deficiencies. The aim of the present investigation was to check whether an optimal salt treatment enhances growth and antioxidant responses of the psammophilic obligate halophyte Sesuvium portulacastrum L. Seedlings were grown for 6 weeks on a nutrient medium (C), diluted 50 times (D), or diluted 50 times and added with 200 mM NaCl (DS). Nutrient deficiencies drastically reduced biomass production in both shoots and roots but did not induce a marked oxidative stress as shown by the 'non-toxic' levels of hydrogen peroxide (H2O2) and malondialdehyde (MDA). In roots, a marked decrease in catalase (CAT) activity seems to keep a certain level of H2O2 for stress signalling purposes. The detrimental effect on growth was slightly alleviated by the optimal salt concentration in DS treatment. H2O2 and MDA concentrations were higher in DS treatment than in D treatment, but they remained at 'nontoxic' levels. The responses of antioxidant enzymes showed the same trend in D and DS treatments but with different magnitudes. Taken together, these results showed that the beneficial effect of salinity on the responses of this psammophilic obligate halophyte to other stresses (i) is limited by the severity of those stresses and (ii) is not mainly based on antioxidant responses. [ABSTRACT FROM AUTHOR]

Sodium salt contamination in the fresh water due to industrial effluents, underground rock salts and inland aquaculture is a major concern needs to be remediated, and subsequently recycled as sustainable bioeconomic strategy. Treatment of saline wastewater requires efficient, cost-effective, rapid, and green technologies, so as to mitigate the negative impacts of salinity on agricultural land. Green technology of phytodesalination is proposed to reduce salinity in the wastewater using salt tolerant plant species. present study was designed with an aim to investigate the sodium (Na+) removal capacity of salt tolerant and high biomass producing macrophytes on synthetic saline wastewater. Sesuvium portulacastrum (sea purslane), Pluchea indica (Indian camphorweed), Typha angustifolia (narrow leaf cattail) and Heliconiapsittacorum (heliconia) were collected, cultivated in the greenhouse, subsequently treated with 0 (control) and 217 mM NaCl (salt stress) for 4 weeks. Overall growth performance, physiological change and Na+ removal rate in root and leaf tissues of the candidate plant species were measured. Plants were able to maintain their growth and physiological abilities except for shoot height in T. angustifolia (reduced by 13.7%) and chlorophyll content in S. portulacastrum (reduced by 64%). Major accumulation of Na+ was recorded in the shoots of S. portulacastrum and P. indica (halophytic plant species) and the roots of T. angustifolia and H. psittacorum (glycophytic plant species). Since T. angustifolia and H. psittacorum have high plant biomass, they showed higher Na+ removal efficiency at 4.4% and 5.7%, respectively; whereas due to lower plant biomass, S. portulacastrum and P. indica resulted in the removal of only 0.6 and 0.8% Na+ from the batch, respectively. Based on the information from this investigation, the selected candidate plant species can further be studied in the constructed wetland together with the controlled environments including optimized flowrate, vertical or horizontal flow system, plant densities and Na-removal rate in relation to swamp habitat. Novelty statement:T. angustifolia and H. psittacorum have high plant biomass, they showed higher Na+ removal efficiency at 4.4% and 5.7%, respectively; whereas due to lower plant biomass, S. portulacastrum and P. indica resulted in removal of only 0.6 and 0.8% Na+ from the batch. Based on the information from this investigation, the selected candidate plant species can further be studied in the constructed wetland together with the controlled environments including optimized flowrate, vertical or horizontal flow system, plant densities and Na-removal rate in relation to swamp habitat. [ABSTRACT FROM AUTHOR]

Abstract Background Na+ extrusion from cells is important for plant growth in high saline environments. SOS1 (salt overly sensitive 1), an Na+/H+ antiporter located in the plasma membrane (PM), functions in toxic Na+ extrusion from cells using energy from an electrochemical proton gradient produced by a PM-localized H+-ATPase (AHA). Therefore, SOS1 and AHA are involved in plant adaption to salt stress. Results In this study, the genes encoding SOS1 and AHA from the halophyte Sesuvium portulacastrum (SpSOS1 and SpAHA1, respectively) were introduced together or singly into Arabidopsis plants. The results indicated that either SpSOS1 or SpAHA1 conferred salt tolerance to transgenic plants and, as expected, Arabidopsis plants expressing both SpSOS1 and SpAHA1 grew better under salt stress than plants expressing only SpSOS1 or SpAHA1. In response to NaCl treatment, Na+ and H+ in the roots of plants transformed with SpSOS1 or SpAHA1 effluxed faster than wild-type (WT) plant roots. Furthermore, roots co-expressing SpSOS1 and SpAHA1 had higher Na+ and H+ efflux rates than single SpSOS1/SpAHA1-expressing transgenic plants, resulting in the former amassing less Na+ than the latter. As seen from comparative analyses of plants exposed to salinity stress, the malondialdehyde (MDA) content was lowest in the co-transgenic SpSOS1 and SpAHA1 plants, but the K+ level was the highest. Conclusion These results suggest SpSOS1 and SpAHA1 coordinate to alleviate salt toxicity by increasing the efficiency of Na+ extrusion to maintain K+ homeostasis and protect the PM from oxidative damage induced by salt stress.

Introduction: Herbal drugs are an important source of antimicrobials and antioxidants. Purpose: This work was designed to carry out the antimicrobial and antioxidant properties of the solvent extracts of the leaves and stem of Sesuvium portulacastrum grown in Saudi Arabia. Materials and Methods: The leaves and stem of the plant were extracted with methanol and chloroform. The antimicrobial property of the methanolic and chloroform extracts was evaluated by the cup plate method, whereas the DPPH method was used for the evaluation of the antioxidant activity. Results: The methanolic extract of the leaves was a more effective antimicrobial product than the chloroform extract against all the tested bacterial strains, namely, E. coli, S. aureus, P. vulgaris, and K. pneumoniae. The methanolic extract of the leaves also showed better antioxidant activity than the methanolic extract of the stem. Its associated antioxidant effect increases the antimicrobial activity of methanolic extract of the leaves. Conclusion: The leaves of Sesuvium portulacastrum have been identified as a useful source to procure natural antimicrobial and antioxidant agents in human health. Therefore, detailed chemical and molecular level investigations are recommended on the leaves of Sesuvium portulacastrum grown in Saudi Arabia. [ABSTRACT FROM AUTHOR]

Plant-based removal of nitrogen (N) and phosphorus (P) from water bodies is an important method for remediation of aquaculture wastewater. In order to acquire knowledge as to how antibiotic residues in wastewater might affect the microbial community and plant uptake of N and P, this study investigated N and P removal by a coastal plant Sesuvium portulacastrum L. grown in aquaculture wastewater treated with 0, 1, 5, or 50 mg/L sulfonamide antibiotics (sulfadiazine, SD) for 28 days and compared the microbial community structure between the water and rhizosphere. Results showed that SD significantly decreased N removal rates from 87.5% to 22.1% and total P removal rates from 99.6% to 85.5%. Plant fresh weights, root numbers, and moisture contents as well as activities of some enzymes in leaves were also reduced. SD changed the microbial community structure in water, but the microbial community structure in the rhizosphere was less affected by SD. The microbial diversity in water was higher than that in the rhizosphere, indicating microbial community differences. Our results showed that the commonly used antibiotic, SD, in aquaculture can inhibit plant growth, change the structure of microbial community, and reduce the capacity of S. portulacastrum plants to remove N and P from wastewater, and also raised alarm about detrimental effects of antibiotic residues in phytoremediation of wastewater.

The complete mitochondrial genome of mangrove associated plant: Sesuvium portulacastrum was analyzed in this paper, which is the first for the genus within the family Aizoaceae. The mitogenome sequence is 392,221 bp in length containing six ribosomal RNA genes, 27 transfer RNA genes, and 36 protein-coding genes. Gene nad1, nad2 and nad5 are the trans-splicing genes. One intron is found in gene ccmFc, two introns are found in genes nad4 and rps3, and four introns are found in gene nad7. Phylogenetic analysis using the maximum likelihood method positioned S. portulacastrum within the monophyletic clades of the family Aizoaceae.

Demonstration of crassulacean acid metabolism (CAM) in species with low usage of this system relative to C3-photosynthetic CO2 assimilation can be challenging experimentally but provides crucial information on the early steps of CAM evolution. Here, weakly expressed CAM was detected in the well-known pantropical coastal, leaf-succulent herb Sesuvium portulacastrum , demonstrating that CAM is present in the Sesuvioideae, the only sub-family of the Aizoaceae in which it had not yet been shown conclusively. In outdoor plots in Panama, leaves and stems of S. portulacastrum consistently exhibited a small degree of nocturnal acidification which, in leaves, increased during the dry season. In potted plants, nocturnal acidification was mainly facultative, as levels of acidification increased in a reversible manner following the imposition of short-term water-stress. In drought-stressed plants, nocturnal net CO2 exchange approached the CO2-compensation point, consistent with low rates of CO2 dark fixation sufficient to eliminate respiratory carbon loss. Detection of low-level CAM in S. portulacastrum adds to the growing number of species that cannot be considered C3 plants sensu stricto , although they obtain CO2 principally via the C3 pathway. Knowledge about the presence/absence of low-level CAM is critical when assessing trajectories of CAM evolution in lineages. The genus Sesuvium is of particular interest because it also contains C4 species. [ABSTRACT FROM AUTHOR]

Many coastal seas are severely eutrophic and required to reduce nutrient concentrations to meet a certain water quality standard. We proposed a method for nutrient removal by planting Sesuvium portulacastrum at the water surface using the floating beds in the aquaculture area of the Dongshan Bay as an example, which is an important net-cage culture base in China and where dissolved inorganic nitrogen (DIN) and dissolved inorganic phosphate (DIP) reach 0.75 mg/L and 0.097 mg/L, respectively far exceeding China's Grade IV water quality standards. Numerical simulations were taken using the ecological model, field observations and field plantation experimental results to assess the environmental restoration effects of planting S. portulacastrum at some certain spatial scales. Our field experiments suggested that the herbs can absorb 377 g/m2 nitrogen and 22.9 g/m2 phosphorus in eight months with an inserting density of ~60 shoot/m2. The numerical experiments show that the greater the plantation area is, the more nutrient removal. Plantation in ~12% of the study area could lower nutrients to the required Grade II standards, i.e., 0.2 mg/L

Abstract Sesuvium portulacastrum , an important mangrove-associated true halophyte belongs to the family Aizoaceae, has excellent salt tolerance. Chloroplasts are the most sensitive organelles involved in the response to salinity. However, the regulation mechanism of chloroplasts of S. portulacastrum under salinity stress has not been reported. In this study, morphological and physiological analyses of leaves and comparative proteomics of chloroplasts isolated from the leaves of S. portulacastrum under different NaCl treatments were performed. Our results showed that the thickness of the palisade tissue, the leaf area, the maximum photochemical efficiency of photosystem II, and the electron transport rate increased remarkably after the plants were subjected to differential saline environments, indicating that salinity can increase photosynthetic efficiency and improve the growth of S. portulacastrum. Subsequently, 55 differentially expressed protein species (DEPs) from the chloroplasts of S. portulacastrum under differential salt conditions were positively identified by mass spectrometry. These DEPs were involved in multiple metabolic pathways, such as photosynthesis, carbon metabolism, ATP synthesis and the cell structure. Among these DEPs, the abundance of most proteins was induced by salt stress. Based on a combination of the morphological and physiological data, as well as the chloroplast proteome results, we speculated that S. portulacastrum can maintain photosynthetic efficiency and growth by maintaining the stability of the photosystem II complex, promoting the photochemical reaction rate, enhancing carbon fixation, developing plastoglobules, and preserving the biomembrane system of chloroplasts under salt stress. [ABSTRACT FROM AUTHOR]

The SpAHA1 gene, encoding a plasma membrane (PM) H+-ATPase (AHA) in Sesuvium portulacastrum, was transformed into Arabidopsis plants, and its expression increased salinity tolerance of transgenic Arabidopsis plants: seed germination ratio, root growth, and biomass of transgenic plants were greater compared to wild-type plants under NaCl treatment condition. Upon salinity stress, both Na+ and H+ effluxes in the roots of SpAHA1 expressing plants were faster than those of untransformed plants. Transformed plants with SpAHA1 had lower Na+ and higher K+ contents relative to wild-type plants when treated with NaCl, resulting in greater K+/Na+ ratio in transgenic plants than in wild-type plants under salt stress. Extent of oxidative stress increased in both transgenic and wild-type plants exposed to salinity stress, but overexpression of SpAHA1 could alleviate the accumulation of hydrogen peroxide (H2O2) induced by NaCl treatment in transgenic plants relative to wild-type plants; the content of malondialdehyde (MDA) was lower in transgenic plants than that in wild-type plants under salinity stress. These results suggest that the higher H+-pumping activity generated by SpAHA1 improved the growth of transgenic plants via regulating ion and reactive oxygen species (ROS) homeostasis in plant cells under salinity stress. [ABSTRACT FROM AUTHOR]

The plasma membrane (PM) Na+/H+ antiporter SOS1 (salt overly sensitive 1) has emerged as a key factor in regulating plant salt tolerance. The SpSOS1 gene, which encodes a PM Na+/H+ antiporter, was cloned from the halophyte Sesuvium portulacastrum and transformed into Arabidopsis sos1 mutant plants. As shown from the results, the SpSOS1 expression complemented the salt sensitivity of the sos1 mutant plants. Upon salinity stress, SpSOS1-transgenic Arabidopsis sos1 mutant seeds displayed higher germination ratio compared to the sos1 mutant. The sos1 mutant plants expressing SpSOS1 grew better and had a lower Na+/K+ ratio than that of the sos1 mutant and wild-type (WT) plants when they were treated with NaCl. In addition, SpSOS1-overexpressed Arabidopsis accumulated less malondialdehyde (MDA) and had a lower level of electrolyte leakage than that in the sos1 mutant and WT plants under salt stress. Furthermore, the SpSOS1 expression in transgenic sos1 mutant plants also increased the transcript levels of some salt stress-related genes, such as AtHKT1;1 (high-affinity K+ transporter 1;1), AtSOS2 (salt overly sensitive 2), AtSCABP8 (SOS3-like calcium binding protein 8), and AtNHX1 (Na+/H+ exchanger 1). These results suggested that SpSOS1 improved the plant salt tolerance by regulating ion homeostasis and protecting the plasma membrane against oxidative damage under salt stress. [ABSTRACT FROM AUTHOR]

Halophytes have superior capacity to withstand soil salinity and are appropriate resources to study the mechanism of salt tolerance which can be harnessed to develop crops to withstand salinity. In this communication, we report the effect of salinity (200 mM NaCl) and elevated carbon dioxide (CO2) treatments in tandem, on select halophytes that have different photosynthetic pathways: C3 and C4. The plants were raised in ambient (380 ppm) and enriched (500 ppm) concentrations of CO2 using a mini-FACE facility. Total chlorophyll content, total soluble sugar concentration, lipid peroxidation level and electrolyte leakage were measured from fresh leaf samples collected at different time points. The results show a positive effect for elevated CO2 concentration on salt tolerance in both C3 and C4 plants, and indicate that halophytes may benefit from rising atmospheric CO2 concentration. The results also suggest that C4 halophytes may benefit from the rising atmospheric CO2 concentration than C3 halophytes. [ABSTRACT FROM AUTHOR]

Sesuvium portulacastrum was treated with mixture of copper, zinc, and cadmium for 60 days, with the concentration of each metal ranging from 0 to 20 mg/L. The tolerance of plants and bioaccumulation of heavy metals were then investigated. The height of S. portulacastrum decreased significantly with increasing heavy metal concentrations from 1 to 20 mg/L. The biomass was adversely impacted when the concentration exceeded 5 mg/L. There were no significant differences in malondialdehyde (MDA) concentration among different treatment groups, while the soluble protein content and superoxide dismutase (SOD) activity decreased with increasing heavy metal concentration. However, the BCF values of the three metals were all higher than 10 and the tolerance in root was up to 1000 mg/kg without causing significant growth inhibition, suggesting that S. portulacastrum should be a potential candidate for phytostabilization for the phytoremediation of polymetallic contaminations in coastal environments. [ABSTRACT FROM AUTHOR]

In order to investigate the tolerance and bioaccumulation of Cd and Cu in the halophyte Sesuvium portulacastrum , seedlings were hydroponically cultured for 30 days using the modified 1/2 Hoagland nutrient solution with different concentrations of Cd (0, 5, 10, 15, and 20 mg L −1 ) and Cu (0, 2.5, 5, 7.5, and 10 mg L −1 ). Afterwards, the seedling height, leaf area, biomass, and mineral element contents (Fe, Mg, Cu, and Zn) in the roots, stems and leaves were measured, and the tolerance index, bioconcentration factor (BCF), transportation index, and removal rate were calculated. The effects of salinity (0‰–30‰) on the growth and bioaccumulation ability of S. portulacastrum under combined Cu/Cd (5 mg L −1 ) exposure were also determined. The results showed that, with an increasing Cd concentration, the biomass and seedling height of S. portulacastrum initially increased and then decreased. The highest leaf biomass and seedlings height was observed in the 10 mg L −1 and 5 mg L −1 Cd treatment group, respectively. Salinity did not affect the biomass of S. portulacastrum but decreased Cd concentration in roots and aboveground tissues and Cu concentration in roots of S. portulacastrum. Cu treatment significantly facilitated the absorption of Mg, Cu, and Zn in roots. With an increasing Cu concentration, the Mg and Fe contents increased in the leaves of S. portulacastrum . In comparison to the above-ground portions, the root showed a higher bioaccumulation ability of Cd and Cu, with the BCF of 341.5 and 211.9, respectively. The BCF and translocation factor (TF) values indicated that S. portulacastrum was not a hyperaccumulator for Cd and Cu, but could be used as a phytostablization plant in heavy metal contaminated coastal environments. [ABSTRACT FROM AUTHOR]

Abiotic stress in the form of gamma irradiation has been shown a potent inducer of oxidative stress in plant cell cultures which produce higher amounts of commercially important secondary metabolites. In the present study, the impact of low doses of gamma irradiation on growth and accumulation of 20-hydroxyecdysone of Sesuvium portulacastrum was investigated. Shoot cultures were established on Murashige and Skoog medium supplemented with indole-3-acetic acid (0.5 mg L) and N -benzylaminopurine (2.0 mg L). Mutations were induced in tissue culture by treating multiple shoots at low doses of gamma irradiation in the range from 5 to 40 Gy. In vitro cell growth and 20-hydroxyecdysone were assessed during MT, MT, MT, and MT generations. A gamma radiation dose of 20 Gy was calculated as 50% of the lethal value (LD). The survival rates of multiple shoot cultures exposed to high doses were gradually reduced in the course of increased order of generations. High-gamma irradiation doses were harmful to growth and 20-hydroxyecdysone production. The accumulation of 20-hydroxyecdysone of 0.139 mg/plant dry weight was significantly two-fold higher than non-irradiated shoot cultures. The stressed shoots increased 13-fold 20-hydroxyecdysone at 20 Gy during the MT generation compared to the yield of the MT generation. The ex vitro plants produced 0.321 mg/plant dry weight of 20-hydroxyecdysone which was remarkably greater than the untreated control. The present study postulated that gamma radiation induced metabolic changes and easy-to-achieve putative mutant comprised with the high amount of 20-hydroxyecdysone. [ABSTRACT FROM AUTHOR]

It is well known that salinity reduces cadmium toxicity in halophytes. However, the possible interference of Cd with the mechanisms of salt tolerance is poorly explored. The aim of this study was to see whether Cd affects salt tolerance mechanisms in the halophyte Sesuvium portulacastrum . S. portulacastrum plants obtained from cuttings were grown in hydroponics for 3 weeks and then exposed to low (0.09 mM) or moderate (200 mM) NaCl concentrations, alone or in combination with 25 μM CdCl 2 . Microscopy observation revealed two strategies of salt tolerance: euhalophytism and secretion of salt by bladder cells. Cadmium exposure hardly influenced the total leaf Na + concentrations. However, Cd supply delayed the salt–induced upregulation of AHA1 (plasma membrane H + -ATPase 1) and SOS1 (plasma membrane Na + transporter “Salt Overly Sensitive 1”), genes that are essential for salt tolerance. Moreover, Cd induced the activation of BADH , coding for betaine aldehyde dehydrogenase, indicating enhanced osmotic stress due to Cd. Sodium-green fluorescence in protoplasts from plants grown with low or high NaCl, alone or in combination with Cd, revealed higher Na + concentrations in the cytoplasm of Cd-exposed plants. Taken together the results indicate interference of Cd with salt tolerance mechanisms in S. portulacastrum . This may have consequences for the efficient use of halophytes in phytoremediation of Cd-contaminated saline soils. [ABSTRACT FROM AUTHOR]