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Betaine aldehyde dehydrogenases (BADHs) are key enzymes in the biosynthesis of glycine betaine, which is an important organic osmolyte that maintains cell structure and improves plant tolerance to abiotic stresses, especially in halotolerant plants. Improving the drought tolerance of crops will greatly increase their yield. In this study, a novel BADH gene named SgBADH from Suaeda glauca was induced by drought stress or abscisic acid. To explore the biological function of SgBADH, the SgBADH gene was transformed into Arabidopsis. Then, we found SgBADH-overexpressing Arabidopsis seedlings showed enhanced tolerance to drought stress. SgBADH transgenic Arabidopsis seedlings also had longer roots compared with controls under drought stress, while SgBADH-overexpressing Arabidopsis exhibited increased glycine betaine accumulation and decreased malondialdehyde (MDA) under drought stress. Our results suggest that SgBADH might be a positive regulator in plants during the response to drought. [ABSTRACT FROM AUTHOR]

NAC (NAM/ATAF1/2/CUC2) transcription factors regulate plant growth and development and stress responses. Because NAC transcription factors are known to play important roles in the regulation of salt tolerance in many plants, we aimed to explore their roles in the halophyte Suaeda glauca. Based on transcriptome sequencing data, we identified 25 NAC transcription factor gene family members. In a phylogenetic tree analysis with Arabidopsis thaliana NAC transcription factors, the SgNACs were divided into 10 groups. The physicochemical properties and conserved domains of the putative proteins, as well as the transcript profiles of their encoding genes, were determined for the 25 SgNAC genes using bioinformatic methods. Most of the S. glauca NAC genes were upregulated to some extent after 24 h of salt stress, suggesting that they play an important role in regulating the salt tolerance of S. glauca. These findings lay the foundation for further research on the functions and mechanisms of the NAC gene family in S. glauca.

Exploring the bacterial community in the S. glauca rhizosphere was of great value for understanding how this species adapted to the salinealkali environment and for the rational development and use of saline-alkali soils. In this study, high-throughput sequencing technology was used to investigate the diversity characteristics and distribution patterns of soil bacterial communities in the rhizosphere of S.glauca-dominated communities in the Hetao Irrigation Distract, Inner Mongolia, China. The relationships among bacterial characteristics, soil physicochemical properties and vegetation in four sampling sites were analyzed. The soil bacterial communities in the rhizosphere of S. glauca-dominated communities were mainly composed of 16 phyla (i.e., Proteobacteria, Actinobacteria, Bacteroidetes, Gemmatimonadetes, Chloroflexi, Acidobacteria, Firmicutes, Planctomycetes, Deinococcus-Thermus, Verrucomicrobia, Saccharibacteria, Cyanobacteria, Nitrospirae, JL-ETNP-Z39, Parcubacteria and Chlorobi), and these populations accounted for more than 99% of the total bacterial community. At the genus level, the main bacterial communities comprised Halomonas, Nitriliruptor, Euzebya and Pelagibius, which accounted for 15.70% of the total bacterial community. An alpha diversity analysis indicated that the richness and diversity of rhizosphere soil bacteria differed significantly among the sampling sites, and the bacterial richness and diversity indices of severe saline-alkali land were higher than those of light and moderate saline-alkali land. The principal component analysis (PCA) and linear discriminant analysis effect size (LEfSe) showed significant differences in the species composition of the rhizosphere soil bacterial community among different sampling sites. A correlation analysis showed that the number of bacterial species exhibited the highest correlation with the soil water content (SWC). The richness and evenness indices were significantly correlated with the SWC and SO42-, KC and Mg2+ concentrations. The electrical conductivity (EC), soluble ions (NaC, CO32- + HCO3-, K+, Ca2+, Mg2+, and SO42+), SWC and vegetation coverage (VC) were the main drivers affecting the changes in its community structure. The bacterial community in the rhizosphere of S. glauca enhanced the adaptability of S. glauca to saline-alkali environment by participating in the cycling process of nutrient elements, the decomposition of organic matter and the production of plant growth regulating substances. These results provided a theoretical reference for further study on the relationship among rhizosphere soil microorganisms and salt tolerance in halophytes. [ABSTRACT FROM AUTHOR]

Suaeda glauca Bunge produces dimorphic seeds on the same plant, with brown seeds displaying non-dormant characteristics and black seeds exhibiting intermediate physiological dormancy traits. Previous studies have shown that black seeds have a very low germination rate under natural conditions, but exogenous GA3 effectively enhanced the germination rate of black seeds. However, the physiological and molecular mechanisms underlying the effects of GA3 on S. glauca black seeds are still unclear. In this study, transcriptomic profiles of seeds at different germination stages with and without GA3 treatment were analyzed and compared, and the TTF, H2O2, O2–, starch, and soluble sugar contents of the corresponding seed samples were determined. The results indicated that exogenous GA3 treatment significantly increased seed vigor, H2O2, and O2– contents but decreased starch and soluble sugar contents of S. glauca black seeds during seed dormancy release. RNA-seq results showed that a total of 1136 DEGs were identified in three comparison groups and were involved mainly in plant hormone signal transduction, diterpenoid biosynthesis, flavonoid biosynthesis, phenylpropanoid biosynthesis, and carbohydrate metabolism pathway. Among them, the DEGs related to diterpenoid biosynthesis (SgGA3ox1, SgKAO and SgGA2ox8) and ABA signal transduction (SgPP2Cs) could play important roles during seed dormancy release. Most genes involved in phenylpropanoid biosynthesis were activated under GA3 treatment conditions, especially many SgPER genes encoding peroxidase. In addition, exogenous GA3 treatment also significantly enhanced the expression of genes involved in flavonoid synthesis, which might be beneficial to seed dormancy release. In accordance with the decline in starch and soluble sugar contents, 15 genes involved in carbohydrate metabolism were significantly up-regulated during GA3-induced dormancy release, such as SgBAM, SgHXK2, and SgAGLU, etc. In a word, exogenous GA3 effectively increased the germination rate and seed vigor of S. glauca black seeds by mediating the metabolic process or signal transduction of plant hormones, phenylpropanoid and flavonoid biosynthesis, and carbohydrate metabolism processes. Our results provide novel insights into the transcriptional regulation mechanism of exogenous GA3 on the dormancy release of S. glauca black seeds. The candidate genes identified in this study may be further studied and used to enrich our knowledge of seed dormancy and germination. [ABSTRACT FROM AUTHOR]

Suaeda glauca (SG), widely applied to restore salinized land, was used to prepare biochar (activated) for the adsorption of bisphenol S (BPS) from water. SG had a high cellulose content and uniform salt ion distribution. The migration pathway of salt ions in halophytes was analyzed via energy dispersive spectrometer (EDS), inductively coupled plasma atomic emission spectrometry (ICP-AES), and X-ray diffraction (XRD). Phosphoric acid impregnation could lead to the leaching of 80.52% of salt ions from SG. The products had high specific surface area (1339 m2/g) and adsorption capacity for BPS (437 mg/g). Response surface methodology indicated that pH and temperature could significantly influence the adsorption capacity. Molecular dynamics and quantum chemistry were used to describe the adsorption process and mechanism. By comparing the pore size distribution and adsorption capacity of different carbons with the simulation results of molecular dynamics, it can be discovered that the effect of micropore size on pollutant adsorption is verifiable through graphite layer modeling. Meanwhile, the presence of salt ions had no significant effect on BPS adsorption capacity. The absorption mechanism might be ascribed to a large specific surface area and π–π bond interactions. [ABSTRACT FROM AUTHOR]

Betaine aldehyde dehydrogenases (BADHs) are key enzymes in the biosynthesis of glycine betaine, which is an important organic osmolyte that maintains cell structure and improves plant tolerance to abiotic stresses, especially in halotolerant plants. Improving the drought tolerance of crops will greatly increase their yield. In this study, a novel BADH gene named SgBADH from Suaeda glauca was induced by drought stress or abscisic acid. To explore the biological function of SgBADH, the SgBADH gene was transformed into Arabidopsis. Then, we found SgBADH-overexpressing Arabidopsis seedlings showed enhanced tolerance to drought stress. SgBADH transgenic Arabidopsis seedlings also had longer roots compared with controls under drought stress, while SgBADH-overexpressing Arabidopsis exhibited increased glycine betaine accumulation and decreased malondialdehyde (MDA) under drought stress. Our results suggest that SgBADH might be a positive regulator in plants during the response to drought.

Suaeda glauca, a halophyte in the Amaranthaceae family, exhibits remarkable resilience to high salt and alkali stresses despite the absence of salt glands or vesicles in its leaves. While there is growing pharmacological interest in S. glauca, research on its secondary metabolites remains limited. In this study, chemical constituents of the aerial parts of S. glauca were identified using 1D- and 2D-NMR experiments, and its biological activity concerning hair loss was newly reported. Eight compounds, including alkaloids (1~3), flavonoids (4~6), and phenolics (7 and 8), were isolated. The compounds, except the flavonoids, were isolated for the first time from S. glauca. In the HPLC chromatogram, quercetin-3-O-β-d-glucoside, kaempferol-3-O-β-d-glucoside, and kaempferol were identified as major constituents in the extract of S. glauca. Additionally, the therapeutic potential of the extract of S. glauca and the isolated compounds 1~8 on the expressions of VEGF and IGF-1, as well as the regulation of Wnt/β-catenin signaling, were evaluated in human follicle dermal papilla cells (HFDPCs) and human umbilical vein endothelial cells (HUVECs). Among the eight compounds, compound 4 was the most potent in terms of increasing the expression of VEGF and IGF-1 and the regulation of Wnt/β-catenin. These findings suggest that S. glauca extract and its compounds are potential new candidates for preventing or treating hair loss. [ABSTRACT FROM AUTHOR]

Endophytic bacteria are promising bacterial fertilizers to improve plant growth under adverse environment. For ecological remediation of coastal wetlands, it was necessary to investigate the effect and interaction of endophytes on halophytes under saline-alkali stress. In this study, an endophytic bacterium strain HK1 isolated from halophytes was selected to infect Suaeda glauca under pH (7 and 8) and salinity gradient (150, 300 and 450 mmol L−1). Strain HK1 was identified as Pantoea ananatis and it had ability to fix nitrogen, dissolve inorganic phosphorus and produce indole-3-aceticacid (IAA). The results showed that strain HK1 could promote the growth of S. glauca seedings when the salinity was less than 300 mmol L−1, in view of longer shoot length and heavier fresh weight. The infected plants could produce more proline to decrease the permeability of cells, which content increased by 26.2%–61.1% compared to the non-infected group. Moreover, the oxidative stress of infected plants was relieved with the malondialdehyde (MDA) content decreased by 16.8%–32.9%, and the peroxidase (POD) activity and catalase (CAT) activity increased by 100%–500% and 6.2%–71.4%, respectively. Statistical analysis revealed that increasing proline content and enhancing CAT and POD activities were the main pathways to alleviate saline-alkali stress by strain HK1 infection, and the latter might be more important. This study illustrated that endophytic bacteria could promote the growth of halophytes by regulation of osmotic substances and strengthening antioxidant activities. This finding would be helpful for the bioremediation of coastal soil. [ABSTRACT FROM AUTHOR]

Suaeda glauca, a halophyte in the Amaranthaceae family, exhibits remarkable resilience to high salt and alkali stresses despite the absence of salt glands or vesicles in its leaves. While there is growing pharmacological interest in S. glauca, research on its secondary metabolites remains limited. In this study, chemical constituents of the aerial parts of S. glauca were identified using 1D- and 2D-NMR experiments, and its biological activity concerning hair loss was newly reported. Eight compounds, including alkaloids (1~3), flavonoids (4~6), and phenolics (7 and 8), were isolated. The compounds, except the flavonoids, were isolated for the first time from S. glauca. In the HPLC chromatogram, quercetin-3-O-β-d-glucoside, kaempferol-3-O-β-d-glucoside, and kaempferol were identified as major constituents in the extract of S. glauca. Additionally, the therapeutic potential of the extract of S. glauca and the isolated compounds 1~8 on the expressions of VEGF and IGF-1, as well as the regulation of Wnt/β-catenin signaling, were evaluated in human follicle dermal papilla cells (HFDPCs) and human umbilical vein endothelial cells (HUVECs). Among the eight compounds, compound 4 was the most potent in terms of increasing the expression of VEGF and IGF-1 and the regulation of Wnt/β-catenin. These findings suggest that S. glauca extract and its compounds are potential new candidates for preventing or treating hair loss.

Suaeda glauca (Bunge) is a pivotal halophyte species, well-known for its rich nutrient content and its importance as a superior vegetable and oil crop, offering significant health benefits for both human and animal consumption. However, the absence of an efficient regeneration technique has severely hindered its genetic development. Consequently, there is an urgent need to establish an effective in vitro organogenesis initiation method for this valuable plant. In this study, our primary objective was to develop a comprehensive protocol for micropropagating S. glauca , primarily capitalizing on the synergistic effects of 6-benzylaminopurine (6-BAP) and indole-6-butyric acid (IBA). We explored the impact of different combinations of 6-benzylaminopurine (6-BAP), 2,4-dichloroacetic acid (2,4-D), and IBA on callus induction, organogenesis, and rooting using various explants (cotyledons, hypocotyls, and leaves) under two different photoperiod regimes during in vitro culture. Our results unveiled noteworthy variations in several variables related to organogenesis. The optimal combination of plant growth regulators (PGRs) for inducing embryonic callus from cotyledon (COT) was pinpointed at 4.44 μM 6-BAP and 2.71 μM 2,4-D. By employing 6-BAP concentrations ranging from 8.88 μM to 13.33 μM, alongside 0.49 μM IBA, 3% sucrose, and 0.3% phytagel in full MS media under light conditions, we achieved a remarkable 100% regeneration rate through the direct organogenesis pathway. Our findings underscore the pivotal role of 6-BAP in triggering multiple shoots and attaining a 3.6% callus differentiation rate, while 0.98 μM IBA resulted in a 65.28% root induction rate, facilitating the successful acclimatization of plants. Based on the synergistic effects of 6-BAP and IBA, we propose a robust protocol for S. glauca organogenesis, which holds great promise for streamlining micropropagation in S. glauca tissue culture. This standardized protocol has the potential to advance genetic improvement and promote the commercial cultivation of S. glauca as a valuable halophyte species. [Display omitted] • In this work, we establish an efficient, simple, and repeatable in vitro plant regeneration method using direct and callus-mediated plant regeneration in the S. glauca. • This is the first report of direct multiple shoot induction and callus proliferation in this plant. • This protocol is ideal for further genetic transformation of S. glauca. • This technique can be used to produce a large number of in vitro plantlets for commercial production. [ABSTRACT FROM AUTHOR]

In the exploitation and development of the muddy coastal zone in Lianyun New Town, Jiangsu Province, much coastal silt soil (CSS) has been formed through reclamation projects, which is difficult to use. The proportion of wild Suaeda glauca increased significantly and became a dominant species in CSS modified by sea-sand mulching (Treated CSS, TCSS), but it was still affected by saline-alkali stress. To use S. glauca efficiently to improve TCSS, high-throughput sequencing technology and conventional soil analysis methods were adopted to investigate the rhizosphere microbial community structure of S. glauca and the physico-chemical properties of TCSS as well as its internal correlation. The results showed that TCSS had low organic matter content, poor nutrients such as N and P, and poor fertility retention. TCSS was still affected by mild or moderate saline-alkali stress, and the total Ca was greater than 1%, so the soil properties indicated a calcareous saline-alkali soil. The growth of S. glauca can reduce soil salinity and increase soil TN content, and its rhizosphere bacterial community was significantly different from that of bulk soil without S. glauca: the rhizosphere was significantly enriched with C-cycle-related bacterium such as organic matter degrading bacteria mariniflexile, photobacterium Sphingomonadaceae, and N-cycle-related bacterium such as nitrogen-fixing bacteria Azoarcus, denitrifying bacteria Pseudomonadaceae; the symbiotic relationship of rhizosphere bacterial community in S. glauca tended to be more complicated, and the functions of nitrogen-respiration, photo-nutrition, and methyl-nutrition were enhanced. Based on the above results, it is reasonable to predict that the interaction between S. glauca and its rhizosphere bacteria in TCSS could promote the process of soil carbon and nitrogen cycles, as to accelerate soil substance transformation and increase soil fertility, thus driving the benign development of TCSS. The results lay a theoretical basis for developing muddy coasts and promoting the precise improvement of TCSS by large-scale cultivation of S. glauca in the local area.

(1) Background: soil salinization has become a global problem that restricts agricultural production; thus, there is a need to explore the special survival strategies of halophytes in saline–alkali environments. (2) Methods: this study conducted a comparative analysis of the differences in metabolites and mineral elements between two indicator plants (Suaeda glauca and Suaeda salsa) in the study area. (3) Results: S. salsa leaves accumulated more total nitrogen (TN), total organic carbon (TOC), calcium (Ca), sodium (Na) and manganese (Mn). The Na/K analysis showed that S. salsa was more tolerant of saline–alkali environments than S. glauca. Metabolite analysis revealed a significant increase in added sugars in S. salsa compared with S. glauca and a significant accumulation of most organic acids associated with the TCA cycle, which suggests an enhancement in the flow of carbon from glycolysis to the TCA cycle. In addition, the content of phenolic substances, such as phenylpropane compounds and flavonols, also changed in saline–alkali environments, which may have promoted the metabolism of organic acids. (4) Conclusions: during the process of plant adaptation to salinity, the central metabolism of S. glauca was nitrogen metabolism, while that of S. salsa was organic acid metabolism. [ABSTRACT FROM AUTHOR]

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Abstract Background Seed dimorphism has been thought to be a bet-hedging strategy that helps plants survive in the disturbed environment and has been widely studied for its ecological adaptation mechanism. Many studies showed that seed-associated microorganisms play an important role in enhancing plant fitness, but information regarding endophytic bacteria associated with dimorphic seeds is limited. This study explores the influence of seed coat structure and seed phytochemical properties on the community composition and diversity of endophytic bacteria of dimorphic seeds of Suaeda glauca. In this study, we used 16S rRNA high-throughput gene sequencing method to compare the community composition and bacterial diversity between brown and black seeds of Suaeda glauca. Results A significant difference was observed in seed coat structure and phytochemical properties between brown and black seeds of S. glauca. Total 9 phyla, 13 classes, 31 orders, 53 families, 102 genera were identified in the dimorphic seeds. The dominant phyla were Proteobacteria, Firmicutes, and Actinobacteria. The results showed that seed dimorphism had little impact on the diversity and richness of endophytic bacterial communities but significantly differs in the relative abundance of the bacterial community between brown and black seeds. At the phylum level, Actinobacteria tend to be enriched significantly in brown seeds. At the genus level, Rhodococcus, Ralstonia, Pelomonas and Bradyrhizobium tend to be enriched significantly in brown seeds, while Marinilactibacillus was mainly found in black seeds. Besides, brown seeds harbored a large number of bacteria with plant-growth-promoting traits, whereas black seeds presented bacteria with enzyme activities (i.e., pectinase, cellulolytic and xylanolytic activities). Conclusion The endophytic bacterial community compositions were significantly different between dimorphic seeds of Suaeda glauca, and play an important role in the ecological adaptation of dimorphic seeds by performing different biological function roles. The endophytic bacterial communities of the dimorphic seeds may be influenced mainly by the seed coat structureand partly by the seed phytochemical characteristics. These findings provide valuable information for better understanding of the ecological adaptation strategy of dimorphic seeds in the disturbed environment.

Abstract Background Suaeda glauca (S. glauca) is a halophyte widely distributed in saline and sandy beaches, with strong saline-alkali tolerance. It is also admired as a landscape plant with high development prospects and scientific research value. The S. glauca chloroplast (cp) genome has recently been reported; however, the mitochondria (mt) genome is still unexplored. Results The mt genome of S. glauca were assembled based on the reads from Pacbio and Illumina sequencing platforms. The circular mt genome of S. glauca has a length of 474,330 bp. The base composition of the S. glauca mt genome showed A (28.00%), T (27.93%), C (21.62%), and G (22.45%). S. glauca mt genome contains 61 genes, including 27 protein-coding genes, 29 tRNA genes, and 5 rRNA genes. The sequence repeats, RNA editing, and gene migration from cp to mt were observed in S. glauca mt genome. Phylogenetic analysis based on the mt genomes of S. glauca and other 28 taxa reflects an exact evolutionary and taxonomic status of S. glauca. Furthermore, the investigation on mt genome characteristics, including genome size, GC contents, genome organization, and gene repeats of S. gulaca genome, was investigated compared to other land plants, indicating the variation of the mt genome in plants. However, the subsequently Ka/Ks analysis revealed that most of the protein-coding genes in mt genome had undergone negative selections, reflecting the importance of those genes in the mt genomes. Conclusions In this study, we reported the mt genome assembly and annotation of a halophytic model plant S. glauca. The subsequent analysis provided us a comprehensive understanding of the S. glauca mt genome, which might facilitate the research on the salt-tolerant plant species.

Coastal silt soil (CSS), hydraulically transported and filled by dredger and mud pump from the bottom of beach in coastal zone in the process of reclamation project, has a high salinity which poses difficulties for coastal development. The use of salt-tolerant plants to improve CSS is a green and efficient method. In this process, the rhizosphere of predominate salt-tolerant plants should enrich more functional microorganisms, which will exert an indispensable ecological influence on plant growth and benign soil transformation. Therefore, comparing the characteristics of plant rhizosphere bacterial communities with different growth capacities on the same CSS can help to find the key rhizosphere hub microorganisms, which will lay a theoretical foundation for the precise improvement of CSS. High-throughput sequencing technology was used to study rhizosphere bacterial diversity of wild salt-tolerant plants (Suaeda glauca, Tripolium vulgare, and Phragmites australis) in the CSS of Lianyun New-town, Lianyungang City, China, through α-diversity, β-diversity, community composition diversity and environmental correlation analysis, and the rhizosphere bacterial functions were predicted. The results showed that the sulfur-oxidizing bacteria (Sulfurovum, Woeseia, and Thioalkalispira) which were dominant in all samples, might impart important salt-stress resistance. Bacteroidetes and sulfate-reducing bacteria Desulfuromonas were enriched in the rhizosphere of S. glauca and P. australis. Bacteroidetes can increase the degradation of organic matter, provide electrons for sulfate-reducing bacteria, and thus promote efficient sulfur-cycling. Sulfate-reducing bacteria can serve as hub bacteria for the growth of salt-tolerant plants by connecting sulfur cycles and organic matter decomposition. In addition, S. glauca, as the dominant plant in CSS, can enrich more functional dominant bacteria, and its rhizosphere bacterial community composition was significantly positively correlated with TN and TOC. These rhizosphere bacteria include phototrophic bacteria Altererythrobacter and methane-oxidizing bacteria Methylophaga related to C cycling, Geothermobacter and Pelobacter related to Fe cycling, and nitrogen-cycle-related bacteria Marinobacterium, Halomonas, and Motiliproteus involved in nitrification/denitrification. This indicates that S. glauca growth can promote the turnover of soil C, N, S, and Fe by enriching these functional bacteria. The analysis of bacterial diversity, as an important ecological indicator, can help to understand the growth of dominant plants in CSS, and the mechanism of benign soil development. The results show that the rhizosphere of S. glauca can enrich a functionally complete bacterial community, which is beneficial to the positive evolution of CSS.

NAC (NAM/ATAF1/2/CUC2) transcription factors regulate plant growth and development and stress responses. Because NAC transcription factors are known to play important roles in the regulation of salt tolerance in many plants, we aimed to explore their roles in the halophyte Suaeda glauca . Based on transcriptome sequencing data, we identified 25 NAC transcription factor gene family members. In a phylogenetic tree analysis with Arabidopsis thaliana NAC transcription factors, the SgNACs were divided into 10 groups. The physicochemical properties and conserved domains of the putative proteins, as well as the transcript profiles of their encoding genes, were determined for the 25 SgNAC genes using bioinformatic methods. Most of the S. glauca NAC genes were upregulated to some extent after 24 h of salt stress, suggesting that they play an important role in regulating the salt tolerance of S. glauca . These findings lay the foundation for further research on the functions and mechanisms of the NAC gene family in S. glauca .

Exploring the bacterial community in the S. glauca rhizosphere was of great value for understanding how this species adapted to the saline-alkali environment and for the rational development and use of saline-alkali soils. In this study, high-throughput sequencing technology was used to investigate the diversity characteristics and distribution patterns of soil bacterial communities in the rhizosphere of S.glauca -dominated communities in the Hetao Irrigation Distract, Inner Mongolia, China. The relationships among bacterial characteristics, soil physicochemical properties and vegetation in four sampling sites were analyzed. The soil bacterial communities in the rhizosphere of S. glauca -dominated communities were mainly composed of 16 phyla (i.e., Proteobacteria, Actinobacteria, Bacteroidetes, Gemmatimonadetes, Chloroflexi, Acidobacteria, Firmicutes, Planctomycetes, Deinococcus-Thermus, Verrucomicrobia, Saccharibacteria, Cyanobacteria, Nitrospirae, JL-ETNP-Z39, Parcubacteria and Chlorobi ), and these populations accounted for more than 99% of the total bacterial community. At the genus level, the main bacterial communities comprised Halomonas, Nitriliruptor, Euzebya and Pelagibius , which accounted for 15.70% of the total bacterial community. An alpha diversity analysis indicated that the richness and diversity of rhizosphere soil bacteria differed significantly among the sampling sites, and the bacterial richness and diversity indices of severe saline-alkali land were higher than those of light and moderate saline-alkali land. The principal component analysis (PCA) and linear discriminant analysis effect size (LEfSe) showed significant differences in the species composition of the rhizosphere soil bacterial community among different sampling sites. A correlation analysis showed that the number of bacterial species exhibited the highest correlation with the soil water content (SWC). The richness and evenness indices were significantly correlated with the SWC and SO 4 2- , K + and Mg 2+ concentrations. The electrical conductivity (EC), soluble ions (Na + , CO 3 2- + HCO 3 - , K + , Ca 2+ , Mg 2+ , and SO 4 2+ ), SWC and vegetation coverage (VC) were the main drivers affecting the changes in its community structure. The bacterial community in the rhizosphere of S. glauca enhanced the adaptability of S. glauca to saline-alkali environment by participating in the cycling process of nutrient elements, the decomposition of organic matter and the production of plant growth regulating substances. These results provided a theoretical reference for further study on the relationship among rhizosphere soil microorganisms and salt tolerance in halophytes., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Dong, Wang, Li, Zhang, Li, Song, Chang, Feng, Pang and Wang.)

Suaeda glauca Bunge produces dimorphic seeds on the same plant, with brown seeds displaying non-dormant characteristics and black seeds exhibiting intermediate physiological dormancy traits. Previous studies have shown that black seeds have a very low germination rate under natural conditions, but exogenous GA 3 effectively enhanced the germination rate of black seeds. However, the physiological and molecular mechanisms underlying the effects of GA 3 on S. glauca black seeds are still unclear. In this study, transcriptomic profiles of seeds at different germination stages with and without GA 3 treatment were analyzed and compared, and the TTF, H 2 O 2 , O 2 - , starch, and soluble sugar contents of the corresponding seed samples were determined. The results indicated that exogenous GA 3 treatment significantly increased seed vigor, H 2 O 2 , and O 2 - contents but decreased starch and soluble sugar contents of S. glauca black seeds during seed dormancy release. RNA-seq results showed that a total of 1136 DEGs were identified in three comparison groups and were involved mainly in plant hormone signal transduction, diterpenoid biosynthesis, flavonoid biosynthesis, phenylpropanoid biosynthesis, and carbohydrate metabolism pathway. Among them, the DEGs related to diterpenoid biosynthesis ( SgGA3ox1 , SgKAO and SgGA2ox8 ) and ABA signal transduction ( SgPP2Cs ) could play important roles during seed dormancy release. Most genes involved in phenylpropanoid biosynthesis were activated under GA 3 treatment conditions, especially many SgPER genes encoding peroxidase. In addition, exogenous GA 3 treatment also significantly enhanced the expression of genes involved in flavonoid synthesis, which might be beneficial to seed dormancy release. In accordance with the decline in starch and soluble sugar contents, 15 genes involved in carbohydrate metabolism were significantly up-regulated during GA 3 -induced dormancy release, such as SgBAM , SgHXK2 , and SgAGLU , etc. In a word, exogenous GA 3 effectively increased the germination rate and seed vigor of S. glauca black seeds by mediating the metabolic process or signal transduction of plant hormones, phenylpropanoid and flavonoid biosynthesis, and carbohydrate metabolism processes. Our results provide novel insights into the transcriptional regulation mechanism of exogenous GA 3 on the dormancy release of S. glauca black seeds. The candidate genes identified in this study may be further studied and used to enrich our knowledge of seed dormancy and germination., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Wang, Xu, Li, Gao, Tao, Song, Li and Li.)

(1) Background: soil salinization has become a global problem that restricts agricultural production; thus, there is a need to explore the special survival strategies of halophytes in saline–alkali environments. (2) Methods: this study conducted a comparative analysis of the differences in metabolites and mineral elements between two indicator plants (Suaeda glauca and Suaeda salsa) in the study area. (3) Results: S. salsa leaves accumulated more total nitrogen (TN), total organic carbon (TOC), calcium (Ca), sodium (Na) and manganese (Mn). The Na/K analysis showed that S. salsa was more tolerant of saline–alkali environments than S. glauca. Metabolite analysis revealed a significant increase in added sugars in S. salsa compared with S. glauca and a significant accumulation of most organic acids associated with the TCA cycle, which suggests an enhancement in the flow of carbon from glycolysis to the TCA cycle. In addition, the content of phenolic substances, such as phenylpropane compounds and flavonols, also changed in saline–alkali environments, which may have promoted the metabolism of organic acids. (4) Conclusions: during the process of plant adaptation to salinity, the central metabolism of S. glauca was nitrogen metabolism, while that of S. salsa was organic acid metabolism.

Suaeda glauca L. is leaf succulent halophyte. Its seed oil content is high and rich in unsaturated fatty acids with high edible and medicinal value. Shoot length and dry weight of S. glauca from saline soils (SS) are higher than that from non-saline soils (NSS). However, the mechanism has not been elucidated. In this work, high-throughput Illumina RNA-sequencing (RNA-seq) was used and photosynthetic traits were evaluated in the species from different habitats, one occurs in SS, and another has been cultivated in NSS for over two decades. There were 1824 DEGs between S. glauca from NSS and SS. Some DEGs were mapped to photosynthesis and photosynthesis-antenna proteins. Notably, genes associated with subunits of photosynthesis and light-capturing complexes (LHCs) showed higher expression levels in the species from SS compared to plants from NSS. This was accompanied by higher potential efficiency of PSII photochemistry (Fv/Fm), actual PSII efficiency (ΦPSII), electron transport rate (ETR), enzyme activity and gene expression of GAPDH and Rubisco in SS seedlings. This study provides evidence that seedlings of S. glauca from SS had higher photosynthetic efficiency compared with that from NSS, thus facilitating their photosynthate accumulation and growth in the SS population, i.e., this characteristic in SS population may be weakened when the species is cultivated in NSS for long time. [Display omitted] • The photoreaction of Suaeda glauca from saline soils (SS) was higher than that from non-saline soils (NSS). • Activity of certain enzymes during carbon assimilation in S. glauca from SS was higher than NSS. • Gene expression of photosynthesis subunits in S. glauca from SS was higher than NSS. • Gene expression of light-harvesting complex in S. glauca from SS was higher than NSS. • S. glauca from SS had higher photosynthetic efficiency compared with that from NSS. [ABSTRACT FROM AUTHOR]

Background: Seed dimorphism has been thought to be a bet-hedging strategy that helps plants survive in the disturbed environment and has been widely studied for its ecological adaptation mechanism. Many studies showed that seed-associated microorganisms play an important role in enhancing plant fitness, but information regarding endophytic bacteria associated with dimorphic seeds is limited. This study explores the influence of seed coat structure and seed phytochemical properties on the community composition and diversity of endophytic bacteria of dimorphic seeds of Suaeda glauca. In this study, we used 16S rRNA high-throughput gene sequencing method to compare the community composition and bacterial diversity between brown and black seeds of Suaeda glauca. Results: A significant difference was observed in seed coat structure and phytochemical properties between brown and black seeds of S. glauca. Total 9 phyla, 13 classes, 31 orders, 53 families, 102 genera were identified in the dimorphic seeds. The dominant phyla were Proteobacteria, Firmicutes, and Actinobacteria. The results showed that seed dimorphism had little impact on the diversity and richness of endophytic bacterial communities but significantly differs in the relative abundance of the bacterial community between brown and black seeds. At the phylum level, Actinobacteria tend to be enriched significantly in brown seeds. At the genus level, Rhodococcus, Ralstonia, Pelomonas and Bradyrhizobium tend to be enriched significantly in brown seeds, while Marinilactibacillus was mainly found in black seeds. Besides, brown seeds harbored a large number of bacteria with plant-growth-promoting traits, whereas black seeds presented bacteria with enzyme activities (i.e., pectinase, cellulolytic and xylanolytic activities). Conclusion: The endophytic bacterial community compositions were significantly different between dimorphic seeds of Suaeda glauca, and play an important role in the ecological adaptation of dimorphic seeds by performing different biological function roles. The endophytic bacterial communities of the dimorphic seeds may be influenced mainly by the seed coat structureand partly by the seed phytochemical characteristics. These findings provide valuable information for better understanding of the ecological adaptation strategy of dimorphic seeds in the disturbed environment. [ABSTRACT FROM AUTHOR]

Background: Suaeda glauca (S. glauca) is a halophyte widely distributed in saline and sandy beaches, with strong saline-alkali tolerance. It is also admired as a landscape plant with high development prospects and scientific research value. The S. glauca chloroplast (cp) genome has recently been reported; however, the mitochondria (mt) genome is still unexplored. Results: The mt genome of S. glauca were assembled based on the reads from Pacbio and Illumina sequencing platforms. The circular mt genome of S. glauca has a length of 474,330 bp. The base composition of the S. glauca mt genome showed A (28.00%), T (27.93%), C (21.62%), and G (22.45%). S. glauca mt genome contains 61 genes, including 27 protein-coding genes, 29 tRNA genes, and 5 rRNA genes. The sequence repeats, RNA editing, and gene migration from cp to mt were observed in S. glauca mt genome. Phylogenetic analysis based on the mt genomes of S. glauca and other 28 taxa reflects an exact evolutionary and taxonomic status of S. glauca. Furthermore, the investigation on mt genome characteristics, including genome size, GC contents, genome organization, and gene repeats of S. gulaca genome, was investigated compared to other land plants, indicating the variation of the mt genome in plants. However, the subsequently Ka/Ks analysis revealed that most of the protein-coding genes in mt genome had undergone negative selections, reflecting the importance of those genes in the mt genomes. Conclusions: In this study, we reported the mt genome assembly and annotation of a halophytic model plant S. glauca. The subsequent analysis provided us a comprehensive understanding of the S. glauca mt genome, which might facilitate the research on the salt-tolerant plant species. [ABSTRACT FROM AUTHOR]

Suaeda species are widely distributed in the coastal areas and are commonly selected as candidates for coastal saline–alkaline soil restoration. In this study, a pot experiment was carried out to investigate the effects of different nutrient levels and salt stresses on the growth and physiological characteristics of Suaeda salsa and Suaeda glauca, two coexisting species exhibiting a spatial segregation in the Yellow River Delta (YRD), China. Our results showed that both Suaeda species can adapt to a high salinity environment (21 g kg−1 NaCl) and display similar regulation strategies, including increased shoot–root ratio, maintaining leaf succulence, and relying on proline and metal ions as osmotic regulators. However, nutrients had a different impact on the salt tolerance of the two species. Under low soil salinity levels, nutrient addition was more beneficial for S. salsa, while under high soil salinity levels, nutrient addition was more beneficial for S. glauca. Our results reveal that the spatial segregation of the two Suaeda species was not driven by salinity. Both species can be used in coastal restoration projects for their high salt-tolerant abilities, but the nutrient addition management should be specific to the species and site soil levels. [ABSTRACT FROM AUTHOR]

Biochar was for the first time produced from Suaeda glauca. The immobilization of Pb and Cd by this biochar and pig manure biochar was examined in two types of soils by diethylene triamine pentaacetic acid (DTPA) extraction. Addition of biochars decreased DTPA extractable Pb and Cd in Fluvo-aquic soil with reduction rates being 11.3%–48.4% and 0.74%–64.9% compared with the control treatment. The pig manure biochar favored the immobilization of Pb and S. glauca biochar favored the immobilization of Cd. Biochars can effectively immobilize heavy metals in Fluvo-aquic soil. However, the addition of biochars increased extractable Pb and Cd in red soil, with pig manure biochars showing greater rates. This is ascribed to that the competition effects of ions released from biochar enhanced the moving of heavy metals from iron and manganese oxides bound form to organic matter bound form, and hence enhanced the mobility and bioavailability of heavy metals. [ABSTRACT FROM AUTHOR]

Episodic deposition has been recognized as a major factor affecting the decomposition rate of detrital material in salt marshes. In this paper, three one-off burial treatments, no burial treatment (0 cm, NBT), current burial treatment (10 cm, CBT) and strong burial treatment (20 cm, SBT), were designed in intertidal zone of the Yellow River Estuary to determine the potential influences of episodic deposition on nutrient (C, N) and heavy metal (Pb, Cr, Cu, Zn, Ni, Mn, Cd, V and Co) variations in decomposing litters of Suaeda glauca. Results showed that although various burial treatments showed no statistical difference in decomposition rate of S. glauca, the values generally followed the sequence of CBT (0.002 403/d) > SBT (0.002 195/d) > NBT (0.002 060/d). The nutrients and heavy metals in decomposing litters of the three burial treatments exhibited different variations except for N, Cu, Cr, Ni and Co. Except for Mn, no significant differences in C, N, Pb, Cr, Cu, Zn, Ni, V and Co concentrations occurred among the three treatments (P > 0.05). With increasing burial depth, Cr and Cd levels generally increased while Cu, Ni and Mn concentrations decreased. Although episodic deposition was generally favorable for C and N release from S. glauca, its influence on release was insignificant. In the three burial treatments, Pb, Cr, Zn, Ni, Mn, V and Co stocks in S. glauca generally evidenced the export of metals from litter to environment, and, with increasing burial depth, the export amounts increased greatly. The S. glauca were particular efficient in binding Cd and releasing Pb, Cr, Zn, Ni, Mn, V and Co, and, with increasing burial depth, stocks of Cu in decomposing litters generally shifted from release to accumulation. The experiment indicated that the potential eco-toxic risk of Pb, Cr, Zn, Ni, Mn, V and Co exposure would be serious as the strong burial episodes occurred in S. glauca marsh. [ABSTRACT FROM AUTHOR]

The complete chloroplast genome (plastome) of Suaeda glauca, an annual halophytic herb, was determined in this study. The plastome was 149,807 bp in size, containing a large single-copy region (82,162 bp), a small single-copy region (18,191 bp), and two inverted repeats regions (24,727 bp). The overall GC content of this plastome was 36.5%. In total, 113 unique genes, including 79 protein-coding genes (PCGs), 30 tRNAs and 4 rRNAs, were annotated. Phylogenomic analysis showed that S. glauca was sister to other Suaeda species.

A new isoflavane, suaeglaucin A (1), which was isolated from the herb of Suaeda glauca (Bunge) Bunge, was elucidated as 5,6,8-trimethoxy-7- hydroxycoumaronochromone based on its MS and 1D and 2D NMR spectroscopic data. The structure of compound 1 was confirmed by X-ray crystallographic analysis. Five known compounds (2-6) were also isolated. All compounds were isolated for the first time from Chenopodiaceae. We found that compounds 2 and 4 possessed moderate antioxidant activity. [ABSTRACT FROM AUTHOR]

Salinity and waterlogging are abiotic stresses that have a significant impact on agricultural production and ecosystem conservation. The response of euhalophyte Suaeda glauca to waterlogging and salinity stresses was investigated. The results revealed that waterlogging markedly decreased seedling emergence. Compared to drained conditions, waterlogging inhibited the shoot dry weight, net photosynthetic rate, stomatal conductance, maximal efficiency of PSII photochemistry and chlorophyll content at salinity. Salinity decreased these values in both waterlogged and drained conditions, while the opposite trend was found in intercellular CO 2 concentrations. Waterlogging increased Na + , Cl − , O 2 - , H 2 O 2 and MDA content in the leaves compared with those in drained conditions, but this was not the case for K + content and SOD and APX activity. Salinity increased these values except that salinity decreased K + content in both waterlogged and drained conditions. In conclusion, S . glauca is not tolerant to combined waterlogging and salinity stresses during both seedling emergence and seedling growth stages, and this trait may limit the distribution of the species in lowland saline areas. [ABSTRACT FROM AUTHOR]

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Background: The structures and soil factors of Suaeda glauca-Suaeda japonica zonal communities and Phragmites australis-S. japonica zonal communities were studied in salt marshes of west and south coasts of South Korea to provide basic data for coastal wetland conservation and restoration. Results: S. glauca community mean length was 67 m and S. japonica community mean length was 567 m in zonal communities, and P. australis and S. japonica community mean length were 57 m and 191 m in zonal communities. Regarding the electrical conductivity, sodium content, and clay contents in Upnae-ri, Shinan-gun, there were significant differences among zonal communities at significance level of 0.05 for two-sided t test. However, other factors were not significantly different. Conclusions: The results indicate that multiple factors such as electronic conductivity, total nitrogen level, clay, and sodium might play important roles in the formation of zonal plant communities of salt marshes. [ABSTRACT FROM AUTHOR]

This study was conducted to evaluate the effects of Suaeda glauca crushed seed on rumen microbial populations, ruminal fermentation, methane emission, and growth performance in lambs. Thirty male Ujumqin lambs (a local breed, average body weight 25.5 ± 1.28 kg) were equally divided into three treatments for a 56 d feeding period. The treatments were control diet (CTR), 80 g of SG seed/kg of diet (SGS80, dry matter (DM) basis), and 160 g of SG seed/kg of diet (SGS160, DM basis). Ruminal samples were collected at 0, 3, 6 and 9 h after the morning feeding on d 28 and 56 to investigate treatment, sampling day, sampling hour, and their interactions effects on ruminal parameters and microorganism population. After the feeding trial, all lambs were moved to respiratory chambers to measure methane emission. Addition of SG seed decreased methanogen ( P < 0.05), protozoa ( P < 0.01), and Fibrobacter succinogenes populations ( P < 0.05). Methanogen and protozoa populations were also affected by an interaction between treatment and sampling day ( P < 0.01) and the effect of SG seed on methanogen and protozoa populations decreased with feeding time. Addition of SG seed did not change populations of fungi, Ruminococcus flavefaciens , and Ruminococcus albus . Lambs fed SG160 diet had lower rumen ammonia nitrogen concentration ( P < 0.01) compared with lambs fed CTR diet. Ammonia nitrogen concentration was affected by an interaction between treatment and sampling day ( P < 0.01). No SG seed effects were found in ruminal pH, total volatile fatty acid concentration and molar proportion of volatile fatty acid. Addition of SG seed increased average daily gain ( P < 0.05) and dry matter intake ( P < 0.05) of lambs but reduced methane emissions ( P < 0.05). No SG seed effects were found in feed efficiency. In conclusion, addition of SG seed seemed to be a feasible means of decreasing methane emissions from lambs by reducing methanogen and protozoa populations. [ABSTRACT FROM AUTHOR]

Twenty-four Merino lambs were randomly assigned to four treatments: control diet (CT) consisting of 300 g concentrates with ad libitum Leymus chinensis hay; C with 150 g (T150), 300 g (T300) and 450 g (T450) Suaeda glauca seed, respectively. Meat quality, fatty acid composition of meat and lipid tissue and antioxidant status of lamb were evaluated. Inclusion of S. glauca seeds significantly increased selenium (Se) concentrations of muscle. The proportions of C18:1 trans -11 in muscle, C18:2 n − 6, PUFA, n − 6 series fatty acids, and the ratios of P:S in rumen contents, as well as the ratios of n − 6:n − 3 in adipose tissue, rumen and duodenum content have been significantly ( P < 0.05) improved with supplementation of S. glauca seeds to lamb diets. No significant effect was found on antioxidant status. The results suggest that S. glauca seed supplementation in lamb diets may change fatty acid composition in tissues and content of digestive tract. [ABSTRACT FROM AUTHOR]

Microbial-phytoremediation is an effective bioremediation technology that introduces petroleum-degrading bacteria and oil-tolerant plants into oil-contaminated soils in order to achieve effective degradation of total petroleum hydrocarbons (TPH). In this work, natural attenuation (NA), microbial remediation (MR, using Acinetobacter sp. Tust-DM21), phytoremediation (PR, using Suaeda glauca), and microbial-phytoremediation (MPR, using both species) were utilized to degrade petroleum hydrocarbons. We evaluated four different biological treatments, assessing TPH degradation rates, soil enzyme activities, and the structure of microbial community in the petroleum-contaminated soil. This finding revealed that the roots of Suaeda glauca adsorbed small amounts of polycyclic aromatic hydrocarbons, causing the structure of soil microbiota community to reshape. The abundance of petroleum-degrading bacteria and plant growth-promoting rhizobacteria (PGPR) has increased, as has microbial diversity. According to correlation research, these genera increased soil enzyme activity, boosted the number of degradation-functional genes in the petroleum hydrocarbon degradation pathway, and accelerated the dissipation and degradation of TPH in petroleum-contaminated soil. This evidence contributes to a better understanding of the mechanisms involved in the combined microbial-phytoremediation strategies for contaminated soil, specifically the interaction between microflora and plants in co-remediation and the effects on the structural reshaping of rhizosphere microbial communities. [Display omitted] • The synergistic effect of oil-degrading bacteria and plant improved TPH degradation. • Actinobacteria sp. Tust-DM21 promoted the growth of native oil-degrading bacteria. • Suaeda glauca promoted PGPR growth while limiting the growth of native bacteria. • Actinobacteria sp. Tust-DM21 showed positively correlated with some PGPR. • A mechanism for oil degradation in the combined remediation has been revealed. [ABSTRACT FROM AUTHOR]

Suaeda glauca is a potential feedstock for ruminants in north-east China in areas of increasing salinity. The characteristics of S. glauca pasture from June to October and effects on intake, digestion and blood metabolites in lambs given increasing proportions of S. glauca in the forage component of a mixed hay/concentrate (50/50) diet were evaluated. Harvest date had a significant effect on dry matter (DM) yield. There were significant increases in DM content, total energy, neutral detergent fibre and acid detergent fibre (ADF), but declines in leaf proportion, crude protein, total ash and sodium contents with maturity. Inclusion of 25% S. glauca hay in a diet significantly improved daily intake of DM, organic matter (OM) and energy compared with T0% and T50% groups. Supplementation at 25 or 50% significantly increased the digestibility of energy, DM, OM and ADF compared with the T0% group. Water intake, urinary excretion, water content of fresh faeces and sodium excretion from urine linearly increased with increasing S. glauca content, but potassium excretion from urine decreased. K and Mg serum contents were significantly increased compared with T0% group when S. glauca made up 50% of diet. This study indicates that S. glauca is a suitable hay when added as 25% of the lamb diet. [ABSTRACT FROM AUTHOR]

• More specific functional bacteria were enriched in the rhizosphere of Suaeda glauca. • The metabolic network of rhizosphere dominant bacteria of S. glauca was established. • Sulfate-reducing bacteria played a hub function for the growth of salt-tolerant plants. • Functionally complete bacterial community is an indicator of soil benign development. Coastal silt soil (CSS), hydraulically transported and filled by dredger and mud pump from the bottom of beach in coastal zone in the process of reclamation project, has a high salinity which poses difficulties for coastal development. The use of salt-tolerant plants to improve CSS is a green and efficient method. In this process, the rhizosphere of predominate salt-tolerant plants should enrich more functional microorganisms, which will exert an indispensable ecological influence on plant growth and benign soil transformation. Therefore, comparing the characteristics of plant rhizosphere bacterial communities with different growth capacities on the same CSS can help to find the key rhizosphere hub microorganisms, which will lay a theoretical foundation for the precise improvement of CSS. High-throughput sequencing technology was used to study rhizosphere bacterial diversity of wild salt-tolerant plants (Suaeda glauca , Tripolium vulgare , and Phragmites australis) in the CSS of Lianyun New-town, Lianyungang City, China, through α-diversity, β-diversity, community composition diversity and environmental correlation analysis, and the rhizosphere bacterial functions were predicted. The results showed that the sulfur-oxidizing bacteria (Sulfurovum , Woeseia , and Thioalkalispira) which were dominant in all samples, might impart important salt-stress resistance. Bacteroidetes and sulfate-reducing bacteria Desulfuromonas were enriched in the rhizosphere of S. glauca and P. australis. Bacteroidetes can increase the degradation of organic matter, provide electrons for sulfate-reducing bacteria, and thus promote efficient sulfur-cycling. Sulfate-reducing bacteria can serve as hub bacteria for the growth of salt-tolerant plants by connecting sulfur cycles and organic matter decomposition. In addition, S. glauca , as the dominant plant in CSS, can enrich more functional dominant bacteria, and its rhizosphere bacterial community composition was significantly positively correlated with TN and TOC. These rhizosphere bacteria include phototrophic bacteria Altererythrobacter and methane-oxidizing bacteria Methylophaga related to C cycling, Geothermobacter and Pelobacter related to Fe cycling, and nitrogen-cycle-related bacteria Marinobacterium , Halomonas , and Motiliproteus involved in nitrification/denitrification. This indicates that S. glauca growth can promote the turnover of soil C, N, S, and Fe by enriching these functional bacteria. The analysis of bacterial diversity, as an important ecological indicator, can help to understand the growth of dominant plants in CSS, and the mechanism of benign soil development. The results show that the rhizosphere of S. glauca can enrich a functionally complete bacterial community, which is beneficial to the positive evolution of CSS. [ABSTRACT FROM AUTHOR]

Bioassay-guided fractionation of the MeOH extract of Suaeda glauca yielded four phenolic compounds, methyl 3,5-di- O-caffeoyl quinate ( 1) and 3,5-di- O-caffeoyl quinic acid ( 2), isorhamnetin 3- O-β-D-galactoside ( 3), and quercetin 3- O-β-D-galactoside ( 4). Compounds 1 and 2 were hepatoprotective against tacrine-induced cytotoxicity in human liver-derived Hep G2 cells with the EC50 values of 72.7±6.2 and 117.2±10.5 μM, respectively. Silybin as a positive control showed an EC50 value of 82.4±4.1 μM. [ABSTRACT FROM AUTHOR]

The complete chloroplast genome (plastome) of Suaeda glauca, an annual halophytic herb, was determined in this study. The plastome was 149,807 bp in size, containing a large single-copy region (82,162 bp), a small single-copy region (18,191 bp), and two inverted repeats regions (24,727 bp). The overall GC content of this plastome was 36.5%. In total, 113 unique genes, including 79 protein-coding genes (PCGs), 30 tRNAs and 4 rRNAs, were annotated. Phylogenomic analysis showed that S. glauca was sister to other Suaeda species. [ABSTRACT FROM AUTHOR]