Salt-tolerant Plant Species Research Articles

Effects of microbial communities during the cultivation of three salt-tolerant plants in saline-alkali land improvement.

Planting vegetation on saline-alkaline land enhances soil fertility and sustainability by improving salt-alkali tolerance. Different salt-tolerant plant species interact with soil microorganisms, enriching bacterial communities and promoting nutrient availability. In this study, mechanisms affecting microbial communities in severely saline-alkaline soils planted with salt-tolerant plants are investigated. Over 4 years, the potential to cultivate three salt-tolerant plant species (tall wheatgrass Agropyron elongatum, chicory Chicorium intybus, and alfalfa Medicago sativa) in severely saline-alkaline soils is compared with a non-cultivated control. Bacterial and fungal communities were characterized through high-throughput sequencing of the 16S rRNA gene V3-V4 region and the V4 region, respectively. Cultivating these three plant species significantly reduces soil electrical conductivity values. Chicory cultivation notably increased soil nutrients, bacterial alpha richness, and fungal alpha diversity and richness. Microbial community structures vary considerably between the control and treatments, significantly correlating with the soil quality index. This index enables an assessment of soil health and fertility by integrating variables such as nutrient content, microbial diversity, and salinity levels. In each plant treatment, particularly alfalfa, the relative abundances of fungal pathogens like Neocosmospora and Gibellulopsis increase, which may pose risks to subsequent crops such as tomatoes, requiring careful consideration in future planting decisions. Conversely, in alfalfa and tall wheatgrass treatments, there was an increase in the relative abundances of fungal genera (e.g., Alternaria and Podospora) that antagonize fungal pathogens, while Paraphoma increased in the chicory treatment. The strong relationship between microorganisms and the rise in pathogen-resistant fungi across different plant treatments highlights robust and beneficial structural characteristics. According to soil quality index scores, each treatment, but especially that of chicory, improved the severely saline-alkaline soil environment.

Investigating the application of the aquaponic paradigm to Litopenaeus vannamei farming

Abstract Aquaponics, a sustainable farming system combining aquaculture and hydroponics, has been widely adopted, used, particularly in freshwater. This study explores the feasibility of adapting the aquaponic model to saltwater conditions, specifically for wastewater treatment from Litopenaeus vannamei farming using the salt-tolerant plant species Rhizophora apiculata Blume. It focuses on plant development and calculates the water treatment effectiveness in terms of nutrient removal in mg of NH4 +, NO2 −, NO3 −, and total phosphorus per gram of plant mass. The first phase involved seedling production, model creation, and testing the plant’s wastewater treatment capabilities. After three months of growth, the plants are subjected to shrimp wastewater, and their nutrient removal efficiency is determined. The obtained data provides essential parameters for the operation of the model during Phase 2. In Phase 1, R. apiculata Blume removed NH4 +, NO2 −, NO3 −, and total phosphorus at 95%, 97%, 59%, and 57% efficiency after seven days, respectively. It focuses on plant development and quantifies the efficiency of water treatment by measuring the removal of nutrients such as NH4 +, NO2 −, NO3 −, and total phosphorus per gram of plant mass.The calculated nutrient removal coefficients per gram of plant mass are NH4 +: 0.007, NO2 −: 0.005, NO3 −: 0.031 and total phosphorus: 0.121. In Phase 2, the designed aquaponic model was developed, which included a shrimp tank with 300 individuals per 1 m3, a fish tank with 50 individuals per 0.5 m3, and a plant growing system. The experimental aquaponic model demonstrates the technical feasibility of using R. apiculata Blume to recycle water in shrimp farming. The model shows potential for scaling up and offers additional benefits, as the leaves R. apiculata of can serve as an herbal source for aquatic species.

Phytoremediation: A Sustainable Approach to Combat Soil Salinity

Soil salinization is a significantconstraint affecting the productivity of agricultural land worldwide. This led to the abandoning of the production of farmcrops on colossalland. Soil salinity inversely affects seed germination and plant growth and influences the plant’s biological activities like photosynthesis, respiration, plant metabolism, enzymatic activities, hormone regulation, etc. Therefore, efforts are being made to bring the saline soil under cultivation by improving itthrough a proper drainage system to drain out the salts orapplying chemical amendments. However, these options are costly and energy-intensive for employment in large areas on a vast scale. In this direction, biologically cost-effective approaches are also being practiced to improve these degraded lands. Phytoremediation, a plant-based approach to improving degraded soil, may be an appropriate option. This is done by the plantation of salt-tolerant plant species, which can remove and leach down excess salts like sodium (Na<sup>+</sup>) from the soil and enhance calcium (Ca<sup>2+</sup>) salts through the cation exchange process from the root zone. During this process, remarkable properties like soil-aggregates stability, root proliferation, soil hydraulic properties, and nutrient availability to plants are also improved. Such improvement in soil properties facilitates the cultivation of less tolerant plants and improves the environment in general and the climatic conditions by enhancing carbon sequestration.

Growing Plants in Water through Hydroponic System

This study investigates the feasibility of utilizing saline water as a nutrient solution in hydroponic systems to grow salt-tolerant plants. We evaluate crop production, nutrient uptake, and plant growth using a range of hydroponic techniques, such as aeroponics, deep water culture, and nutrient film, in comparison to conventional soil-based procedures. While examining the effects of different salinity levels on plant physiology, the study focuses on optimizing important characteristics in the hydroponic solution, such as pH, electrical conductivity, and nutrient concentration. According to preliminary research, some salt-tolerant plant species grow and adapt better in hydroponic systems, which presents a viable method for saline-tolerant sustainable agriculture. This study adds important knowledge for creating effective and sustainable solutions to problems with food production in areas where soil salinity is a problem.

Genome-wide identification of HDAC members and function analysis of PnHDT1/2 in salt stress response in Phyla nodiflora (L.) Greene

Reversible histone acetylation and deacetylation play an essential role in regulating chromatin structure and gene expression. Histone deacetylases (HDACs) catalyze the removal of acetyl groups from lysine residues of core histones, resulting in closed chromatin structure and transcription repression. Although the HDCAs have been extensively studied in model plants, the HDAC members have not been identified in Phyla nodiflora (L.) Greene (P. nodiflora), a salt-tolerant plant species. Here, 17 PnHDAC genes were identified in the genome of P. nodiflora. Phylogenetic analysis displayed that the PnHDACs were classified into three groups, the RPD3/HDA1-group (11 members), the SIR2-group (2 members) and the plant-specific HD2-group (4 members). Transcription analysis displayed that the gene expression patterns of PnHDACs were affected by salt stress in P. nodiflora seedlings. PnHDT1 and PnHDT2, two HD2-type HDAC proteins were found to be subcellular localized in the nucleolus. Furthermore, overexpressing PnHDT1 and PnHDT2 in Arabidopsis decreased the sensitivity to plant hormone abscisic acid whereas reduced the tolerance to salt stress during seed germination and seedling stages. Overall, our work identified the PnHDAC gene family for the first time in P. nodiflora and revealed an involvement of PnHDT1 and PnHDT2 in salt stress tolerance, which may contribute to uncover the mechanism of P. nodiflora in adaption to salt environments.

Synanthropic spread of some salt tolerant plant species along roadsides in the continental part of Croatia

Our research was carried out in northern Croatia from 2018 to 2022 and we investigated the distribution of salt-tolerant plant species along roads (mainly along motorways) in a total of 51 study sites. We were the first to detect Cochlearia danica, a halophyte characterized by an Atlantic distribution, in the Croatian flora. We demonstrated the distinct roadside spread of Desmazeria marina, Parapholis incurva and Sagina maritima in a northerly direction towards the interior of the mainland. We recorded the mass occurrence of several salt-tolerant species already well documented in Central Europe along the surveyed motorways (e.g. Plantago coronopus, Spergularia marina) and provide data on other weeds that have spread along major roads. Three species found (Desmazeria marina, Puccinellia distans subsp. distans, Parapholis incurva) are included in the Croatian Red List.

Cryptic invasion suggested by a cytogeographic analysis of the halophytic Puccinellia distans complex (Poaceae) in Central Europe.

Despite the wealth of studies dealing with the invasions of alien plants, invasions of alien genotypes of native species (cryptic invasions) have been vastly neglected. The impact of cryptic invasions on the biodiversity of plant communities can, however, be significant. Inland saline habitats and halophytes (i.e., salt-tolerant plant species) are especially threatened by this phenomenon as they inhabit fragmented remnants of largely destroyed habitats, but at the same time some of these halophytic species are rapidly spreading along salt-treated roads. To study potential cryptic invasion of halophytes, the patterns of genome size and ploidy variation in the Puccinellia distans complex (Poaceae), the most rapidly spreading roadside halophyte in Central Europe, were investigated. DNA flow cytometry with confirmatory chromosome counts were employed to assess ploidy levels of 1414 individuals from 133 populations of the P. distans complex. In addition, climatic niche modelling was used to predict the distributions of selected cytotypes. Eight groups differing in ploidy level and/or genome size were discovered, one diploid (2x; 2n = 14), two tetraploid (4xA, 4xB; 2n = 28), one pentaploid (5x; 2n = 35), three hexaploid (6xA, 6xB, 6xC; 2n = 42), and one heptaploid (7x; 2n = 49). The hexaploids (mostly the 6xC cytotype) were widespread through the study area, spreading intensively in both anthropogenic and natural habitats and probably hybridizing with the natural habitat dwelling tetraploids. In contrast, the non-hexaploid cytotypes rarely spread and were predominantly confined to natural habitats. The extensive spread of the hexaploid cytotypes along roadsides has most likely facilitated their incursion into natural habitats. The colonization of new natural habitats by the hexaploids may pose a threat to the indigenous Puccinellia populations by compromising their genetic integrity and/or by outcompeting them.

The Impact of the Growing Substrate on Morphological and Biochemical Features of Salicornia europaea L.

Nowadays, intensive agriculture correlated with the impact of climate change has led to nutrient soil depletion and the salinization of agricultural lands, making them unsuitable for conventional agricultural crops, with a direct impact on the food industry. Therefore, it is necessary to find sustainable alternative solutions that satisfy the needs of both consumers and food production. One such solution may be represented by salt-tolerant species that can fulfill food requirements. One of the most promising salt-tolerant plant species that can be used is Salicornia europaea L. The present work was conducted in greenhouse conditions, and the adaptability of the species on different cultivation substrates was investigated by means of monitoring the plant indicators such as cuticle, epidermis, parenchyma, polyphenols content, and minerals. Moreover, the correlation between the polyphenol and mineral contents was highlighted. Therefore, three cultivation substrates with different levels of salinity/electrical conductivity were used. The reference (I) for biochemical indicators was represented by the plant grown in natural salinity conditions in the Southeast region of Romania. The results indicate that Salicornia europaea L. can be grown on different cultivation substrates other than salted soils, the plant showing the capacity to accumulate bioactive compounds similar to natively grown ones.

Metabolomics analysis unveils important changes involved in the salt tolerance of Salicornia europaea.

Salicornia europaea is one of the world's salt-tolerant plant species and is recognized as a model plant for studying the metabolism and molecular mechanisms of halophytes under salinity. To investigate the metabolic responses to salinity stress in S. europaea, this study performed a widely targeted metabolomic analysis after analyzing the physiological characteristics of plants exposed to various NaCl treatments. S. europaea exhibited excellent salt tolerance and could withstand extremely high NaCl concentrations, while lower NaCl conditions (50 and 100 mM) significantly promoted growth by increasing tissue succulence and maintaining a relatively stable K+ concentration. A total of 552 metabolites were detected, 500 of which were differently accumulated, mainly consisting of lipids, organic acids, saccharides, alcohols, amino acids, flavonoids, phenolic acids, and alkaloids. Sucrose, glucose, p-proline, quercetin and its derivatives, and kaempferol derivatives represented core metabolites that are responsive to salinity stress. Glycolysis, flavone and flavonol biosynthesis, and phenylpropanoid biosynthesis were considered as the most important pathways responsible for salt stress response by increasing the osmotic tolerance and antioxidant activities. The high accumulation of some saccharides, flavonoids, and phenolic acids under 50 mM NaCl compared with 300 mM NaCl might contribute to the improved salt tolerance under the 50 mM NaCl treatment. Furthermore, quercetin, quercetin derivatives, and kaempferol derivatives showed varied change patterns in the roots and shoots, while coumaric, caffeic, and ferulic acids increased significantly in the roots, implying that the coping strategies in the shoots and roots varied under salinity stress. These findings lay the foundation for further analysis of the mechanism underlying the response of S. europaea to salinity.

Physiological adaptability of Salvadora oleoides to sodicity and salinity stress

An experiment was conducted in microplots at ICAR-Central Soil Salinity Research Institute, Karnal, Haryana during 2013–16 to study the adaptive response of Salvadora oleoides, a facultative halophyte under saline, sodic and mixed saline-sodic conditions. S. oleoides was not able to survive at higher sodicity (pH ~ 10.0) and salinity (ECe ~ 35 dS/m) as well as on the mixed sodicity and salinity levels (pH ~ 9.0 along with ECe ~ 10, 15, 20 dS/m). Stress either salinity or sodicity brought reduction in plant height, chlorophyll content and gas exchange attributes, but S. oleoides maintained gaseous exchange at moderate stress level. S. oleoides accumulated 4 fold higher proline under sodic stress and 6 fold under salinity stress. Other osmolytes, TSS and soluble protein decreased with stress intensification to maintain osmotic balance. In comparison to control, sodicity enhanced Na+ and Cl- by 54.57% and 20.33%, while under salinity, Na+ was enhanced by 141.52–256.09% and Cl- by 47.83–115.58% at ECe ~ 15 and 25 dS/m, respectively. Inspite of such higher increase in Na+ and Cl-, S. oleoides retained good amount of mean K+ (1.22%) in leaf tissue. S. oleoides also maintained leaf Na+/K+ below 1.0 under stress condition of pH ~ 9.5 and ECe ~ 15 dS/m. Based on the studied physio-biochemical analysis, Salvadora oleoides exhibited good adaptive potential under moderate salinity and sodicity stress and could be used as a promising salt-tolerant plant species for plantation in salt affected areas.

Physio-Biochemical Responses of Three Aquilegia Species Seedlings to Salt Stress

Road deicing salts are widely used during winter in northern China, which makes it essential to choose proper salt-tolerant plant species in urban landscapes. Columbine (Aquilegia) is a herb with high ornamental and commercial values. This study evaluated three Aquilegia species (A. oxysepala, A. parviflora, and A. viridiflora) for salt tolerance by monitoring their germination state under different electrical conductivity (EC) of 0.1 dS·m−1 (distilled water), 1.0 dS·m−1, 2.0 dS·m−1, 3.0 dS·m−1, 4.0 dS·m−1, 5.0 dS·m−1, 6.0 dS·m−1, physio-biochemical responses to different EC of 0.3 dS·m−1 (tap water), 5.0 dS·m−1, and 10.0 dS·m−1. The germination and growth parameters, visual scores, dry weight, leaf stomatal conductance, photosynthetic rate, and chlorophyll contents of three species decreased under salt stress, which was opposite to the changes of electrolyte leakage, malondialdehyde, proline, and soluble sugar contents. Superoxide dismutase and peroxidase activity trend differently among species. These results showed that the germination threshold of three species was 6.0 dS·m−1. A. oxysepala was the most salt-tolerant species, with a tolerance threshold of soil conductivity in 2.83 dS·m−1, followed by A. viridiflora and A. parviflora. Therefore, A. oxysepala is suitable for planting as a ground cover in urban areas where deicing salt is applied.

Effect of Salinity and Nitrogen Fertilization Levels on Growth Parameters of Sarcocornia fruticosa, Salicornia brachiata, and Arthrocnemum macrostachyum

Salinity negatively influences crop growth, but several salt-tolerant plant species (halophytes) are viable crops. Sarcocornia fruticosa (ecotypes EL and VM) is currently cultivated, but there is demand for new crop candidates and higher biomass production. Salicornia brachiata Roxb. and Arthrocneum macrostachyum L. are considered novel crops, and to realize their potential, their response to salinity and nitrogen nutrition was compared to S. fruticosa ecotypes. Experiments revealed that higher N supplemented with lower NaCl significantly increased fresh and dry shoot biomass. Lower biomass was obtained at lower nitrogen supplemented with elevated NaCl, whereas total soluble solids content positively correlated with NaCl fertigation in both Sarcocornia ecotypes. Protein content increased with a lower nitrogen supply. Anthocyanins and oxygen radical absorbance capacity were highest in S. fruticosa EL and A. macrostachyum at higher NaCl supply. The results show that halophytes have a variety of strategies to cope with high NaCl, even between ecotypes of the same species. Notably, repetitive harvesting of S. brachiata delayed flowering enabling year-round biomass production. Additionally, S. brachiata accumulated higher biomass than Sarcocornia VM when grown in a greenhouse at higher radiation than in a growth room and strongly supports its inclusion as a cash-crop halophyte.

An Insight into Abiotic Stress and Influx Tolerance Mechanisms in Plants to Cope in Saline Environments.

Simple SummaryThis review focuses on plant growth and development harmed by abiotic stress, primarily salt stress. Salt stress raises the intracellular osmotic pressure, leading to hazardous sodium buildup. Plants react to salt stress signals by regulating ion homeostasis, activating the osmotic stress pathway, modulating plant hormone signaling, and altering cytoskeleton dynamics and cell wall composition. Understanding the processes underlying these physiological and biochemical responses to salt stress could lead to more effective agricultural crop yield measures. In this review, researchers outline recent advances in plant salt stress control. The study of plant salt tolerance processes is essential, both theoretically and practically, to improve agricultural output, produce novel salt-tolerant cultivars, and make full use of saline soil. Based on past research, this paper discusses the adverse effects of salt stress on plants, including photosynthesis suppression, ion homeostasis disturbance, and membrane peroxidation. The authors have also covered the physiological mechanisms of salt tolerance, such as the scavenging of reactive oxygen species and osmotic adjustment. This study further identifies specific salt stress-responsive mechanisms linked to physiological systems. Based on previous studies, this article reviews the current methodologies and techniques for improving plant salt tolerance. Overall, it is hoped that the above-mentioned points will impart helpful background information for future agricultural and crop plant production.Salinity is significant abiotic stress that affects the majority of agricultural, irrigated, and cultivated land. It is an issue of global importance, causing many socio-economic problems. Salt stress mainly occurs due to two factors: (1) soil type and (2) irrigation water. It is a major environmental constraint, limiting crop growth, plant productivity, and agricultural yield. Soil salinity is a major problem that considerably distorts ecological habitats in arid and semi-arid regions. Excess salts in the soil affect plant nutrient uptake and osmotic balance, leading to osmotic and ionic stress. Plant adaptation or tolerance to salinity stress involves complex physiological traits, metabolic pathways, the production of enzymes, compatible solutes, metabolites, and molecular or genetic networks. Different plant species have different salt overly sensitive pathways and high-affinity K+ channel transporters that maintain ion homeostasis. However, little progress has been made in developing salt-tolerant crop varieties using different breeding approaches. This review highlights the interlinking of plant morpho-physiological, molecular, biochemical, and genetic approaches to produce salt-tolerant plant species. Most of the research emphasizes the significance of plant growth-promoting rhizobacteria in protecting plants from biotic and abiotic stressors. Plant growth, survival, and yield can be stabilized by utilizing this knowledge using different breeding and agronomical techniques. This information marks existing research areas and future gaps that require more attention to reveal new salt tolerance determinants in plants—in the future, creating genetically modified plants could help increase crop growth and the toleration of saline environments.

Combined transcriptomic and metabolomic analysis reveals the potential mechanism of seed germination and young seedling growth in Tamarix hispida

BackgroundSeed germination is a series of ordered physiological and morphogenetic processes and a critical stage in plant life cycle. Tamarix hispida is one of the most salt-tolerant plant species; however, its seed germination has not been analysed using combined transcriptomics and metabolomics.ResultsTranscriptomic sequencing and widely targeted metabolomics were used to detect the transcriptional metabolic profiles of T. hispida at different stages of seed germination and young seedling growth. Transcriptomics showed that 46,538 genes were significantly altered throughout the studied development period. Enrichment study revealed that plant hormones, such as auxin, ABA, JA and SA played differential roles at varying stages of seed germination and post-germination. Metabolomics detected 1022 metabolites, with flavonoids accounting for the highest proportion of differential metabolites. Combined analysis indicated that flavonoid biosynthesis in young seedling growth, such as rhoifolin and quercetin, may improve the plant’s adaptative ability to extreme desert environments.ConclusionsThe differential regulation of plant hormones and the accumulation of flavonoids may be important for the seed germination survival of T. hispida in response to salt or arid deserts. This study enhanced the understanding of the overall mechanism in seed germination and post-germination. The results provide guidance for the ecological value and young seedling growth of T. hispida.

Disclosing the bioactive metabolites involved in the in vitro anthelmintic effects of salt-tolerant plants through a combined approach using PVPP and HPLC-ESI-MSn

Strategies to reduce dependence on synthetic drugs for the treatment of gastrointestinal nematodes (GIN) infections in ruminants include the search for novel anthelmintic scaffolds on plants, yet salt-tolerant plants remain overlooked. This study aims to evaluate the in vitro anthelmintic properties of selected salt-tolerant plants against GIN, and identify the potential bioactive secondary metabolites involved. For that purpose, 80% acetone/water extracts were prepared from dried biomass of aerial organs of nine salt-tolerant plant species and tested against Haemonchus contortus and Trichostrongylus colubriformis by the Larval Exsheathment Inhibition Assay (LEIA) and Egg Hatching Inhibition Assay (EHIA). Pistacia lentiscus, Limoniatrum monopetalum, Cladium mariscus and Helychrisum italicum picardi were the most active in both GIN and life stages. To investigate the role of polyphenols in the anthelmintic activity, four selected extracts were treated with polyvinylpolypyrrolidone (PVPP), and non-treated and treated samples were further characterized by high-performance liquid chromatography with electrospray ionization mass spectrometric detection (HPLC-ESI-MSn). While polyphenols seem responsible for the EHIA properties, they are partially accountable to LEIA results. Several phenolics involved in the anthelmintic effects were identified and discussed. In sum, these species are rich sources of anthelmintic compounds and, therefore, are of major interest for nutraceutical and/or phytotherapeutic applications against GIN in ruminants.

The First De Novo Transcriptome Assembly and Transcriptomic Dynamics of the Mangrove Tree Rhizophora stylosa Griff. (Rhizophoraceae)

Mangroves are salt-tolerant plant species that grow in coastal saline water and are adapted to harsh environmental conditions. In this study, we de novo assembled and functionally annotated the transcriptome of Rhizophora stylosa, the widely distributed mangrove from the largest mangrove family (Rhizophoraceae). The final transcriptome consists of 200,491 unigenes with an average length, and N50 of 912.7 and 1334 base pair, respectively. We then compared the genome-wide expression profiles between the two morphologically distinct natural populations of this species growing under different levels of salinity depending on their distance from the ocean. Among the 200,491 unigenes, 40,253 were identified as differentially expressed between the two populations, while 15,741 and 24,512 were up- and down-regulated, respectively. Functional annotation assigned thousands of upregulated genes in saline environment to the categories related to abiotic stresses such as response to salt-, osmotic-, and oxidative-stress. Validation of those genes may contribute to a better understanding of adaptation in mangroves species. This study reported, for the first time, the transcriptome of R. stylosa, and the dynamic of it in response to salt stress and provided a valuable resource for elucidation of the molecular mechanism underlying the salt stress response in mangroves and other plants that live under stress.

Relevance of nitrogen availability on the phytochemical properties of Chenopodium quinoa cultivated in marine hydroponics as a functional food

Chenopodium quinoa is a salt tolerant plant species of high nutritional value with potential to act as an extractive species under marine integrated multi-trophic aquaculture (IMTA). This study aimed to assess the growth performance and antioxidant content and activity of C. quinoa cultivated in saline hydroponics under contrasting nitrogen concentrations mimicking different aquaculture effluents described in literature. Seedlings were cultivated under greenhouse conditions in a modified Hoagland solution with a salinity of 20 g l−1 artificial sea salt and four nitrogen concentrations: 20 mg l−1 (N20); 40 mg l−1 (N40); 100 mg l−1 (N100) and 200 mg l−1 (N200). After 4 weeks, leaf chlorophyll content and biomass gain were determined. Total flavonoids, total phenols and contents of elements were analyzed in C. quinoa leaves and shoot tips. Antioxidant capacity was quantified using oxygen radical absorbance capacity assay (ORAC). In treatments N100 and N200, C. quinoa presented higher biomass gain and lower antioxidant content and activity in its leaves and shoot tips. In contrast, in treatment N20 higher antioxidant content and activity were recorded, revealing the existence of stress inducing conditions during the experimental period. Shoot tips of these plants contained higher nitrogen and mineral contents than leaves. This approach may set the stage to develop a sustainable methodology to modulate the secondary metabolism of C. quinoa and enhance its value as functional food when cultured using marine aquaponics in IMTA systems.

From natural habitats to successful application - Role of halophytes in the treatment of saline wastewater in constructed wetlands with a focus on Latin America

In many parts of the world wastewater is not treated at all or only to a limited extend because there are no resources available to establish an efficient wastewater treatment plant and there are also insufficient resources for operation and maintenance costs. Constructed wetlands (CWs) are nature-based solutions to treat wastewater in a highly cost-efficient manner. They can be very efficient and effective when well designed and maintained. Latin America is rich in saline natural wetlands. These can be used as prototypes for CWs treating saline process or wastewater. Similar to natural saline wetlands CWs can deliver several ecosystem services. This review focuses on saline wetlands and will first present the protagonists, the salt-tolerant plant species belonging to the halophytes with respect to their physiological and biochemical functions in wetlands. In a second step, their remediating activities which are used in many ways by local people will be shown in an exemplary manner. A number of CWs established in different regions, including Latin America, will be introduced as case studies. Halophytes are already being used in a number of CWs as biofilter but their usage could be increased, for example to treat aquaculture effluents and the biomass has a high potential for valuable compounds (i.e. metabolites) or for bioenergy production. Lastly, aspects of sustainability and ecosystem services of saline natural and constructed wetlands are shown with an emphasis on charting a way forward for the future holistic implementation of saline systems in Latin America.

Pharmacological Insights into Halophyte Bioactive Extract Action on Anti-Inflammatory, Pain Relief and Antibiotics-Type Mechanisms.

The pharmacological activities in bioactive plant extracts play an increasing role in sustainable resources for valorization and biomedical applications. Bioactive phytochemicals, including natural compounds, secondary metabolites and their derivatives, have attracted significant attention for use in both medicinal products and cosmetic products. Our review highlights the pharmacological mode-of-action and current biomedical applications of key bioactive compounds applied as anti-inflammatory, bactericidal with antibiotics effects, and pain relief purposes in controlled clinical studies or preclinical studies. In this systematic review, the availability of bioactive compounds from several salt-tolerant plant species, mainly focusing on the three promising species Aster tripolium, Crithmum maritimum and Salicornia europaea, are summarized and discussed. All three of them have been widely used in natural folk medicines and are now in the focus for future nutraceutical and pharmacological applications.

Assembly and comparative analysis of the complete mitochondrial genome of Suaeda glauca

BackgroundSuaeda 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.ResultsThe 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.ConclusionsIn 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.