Explore the vast range of titles available.

A developing trend in stormwater treatment and management is the use of green technologies. Plant biofilters have been gaining increasing use in support of green technology objectives. This technical note reports on the development and preliminary testing of a laboratory-scale plant biofilter prototype for ammonia removal using a South African native plant species (Juncus efusus ). The prototype design was based on a conceptual model for nitrogen fixation, plant uptake, bacterial nitrification and soil sorption. Additionally, a plug compartment was incorporated into the design to simulate plug flow as part of the conceptual model. Biofilter models with and without inoculated bacteria were compared. Ammonia reduction, nitrite and nitrate formation were observed. Results showed that the inoculated plant biofilter performed best, with an average of 61% reduction in ammonia within the filter compared to 15% in the normal plant biofilter. The incorporation of a plug compartment aided in slowing down the ammonia infiltration rate, increasing the retention time, and allowing for nitrification to occur.

Background Sodium Dodecyl Sulfate (SDS) an anionic surfactant pollutant has emerged as a serious hazard to the aquatic and terrestrial environment. Due to physical and chemical methodological difficulties for SDS removal, phytoremediation techniques are efficient alternative strategies to tackle such adversities. Juncus acutus L. ( J. acutus ) is a pioneer wetland species that has been recently exploited for phytoremediation purposes. To our knowledge, the role of exogenous hydrogen peroxide (H 2 O 2 ), in improving the phytoextraction of SDS has not been examined yet. In this study, pretreatment foliar spray of H 2 O 2 (15 mM) combined with two levels of SDS (50 and 100 ppm) in water culture was evaluated to remove SDS contamination and add value to the phytoremediation process. Results The outcomes revealed that J. acutus has considerable translocation and bioaccumulation abilities for SDS and can be utilized as an appropriate hyperaccumulator in SDS-contaminated sites. However, the involvement of H 2 O 2 extended phytoremediation capacity and successive removal of SDS. H 2 O 2 significantly assisted in increasing SDS remediation via more accumulation in J. acutus tissues by 29.9 and 112.4% and decreasing SDS concentration in culture media by 33.3 and 27.3% at 50 and 100 ppm SDS, respectively. Bioaccumulation factor (BCF) increased by 13.8 and 13.2%, while translocation factor (TCF) positively maximized by 82.4 and 76.2% by H 2 O 2 application at 50 and 100 ppm SDS, respectively. H 2 O 2 pretreatment could drive the decline in biochemical attributes in SDS-affected plants by modulating stress tolerance indices, pigments, water relations, proline content, enzymatic activities, and further, reduced oxidative stress in terms of electrolyte leakage, cellular H 2 O 2 , malondialdehyde (MDA) accumulation. Conclusions H 2 O 2 could play a potential role in maximizing phytoremediation capacity of SDS by J. acutus in polluted sites.

The majority of sequenced genomes in the monocots are from species belonging to Poaceae, which include many commercially important crops. Here, we expand the number of sequenced genomes from the monocots to include the genomes of 4 related cyperids: Carex cristatella and Carex scoparia from Cyperaceae and Juncus effusus and Juncus inflexus from Juncaceae. The high-quality, chromosome-scale genome sequences from these 4 cyperids were assembled by combining whole-genome shotgun sequencing of Nanopore long reads, Illumina short reads, and Hi-C sequencing data. Some members of the Cyperaceae and Juncaceae are known to possess holocentric chromosomes. We examined the repeat landscapes in our sequenced genomes to search for potential repeats associated with centromeres. Several large satellite repeat families, comprising 3.2–9.5% of our sequenced genomes, showed dispersed distribution of large satellite repeat clusters across all Carex chromosomes, with few instances of these repeats clustering in the same chromosomal regions. In contrast, most large Juncus satellite repeats were clustered in a single location on each chromosome, with sporadic instances of large satellite repeats throughout the Juncus genomes. Recognizable transposable elements account for about 20% of each of the 4 genome assemblies, with the Carex genomes containing more DNA transposons than retrotransposons while the converse is true for the Juncus genomes. These genome sequences and annotations will facilitate better comparative analysis within monocots.

Phenanthrenes represent a relatively small group of aromatic secondary metabolites, which can be divided into three main subgroups (mono-, di-, and triphenanthrenes). Phenanthrenes are reported as an intensively researched field in phytochemistry according to their structural diversity and promising biological activities. Because of their limited occurrence phenanthrenes are considered to be as important taxonomic markers. Juncaceae is a relatively large plant family divided into seven genera of which Juncus and Luzula are the most important ones from phytochemical and pharmacological points of view. To date, almost one hundred natural phenanthrenes have been isolated but only from eight ( Juncus acutus , J. effusus , J. inflexus , J. maritimus , J. roemerianus , J. setchuensis , J. subulatus , and Luzula luzuloides ) Juncaceae species, including mono-, and diphenanthrenes, and phenanthrene glucosides. Great deal of the isolated compounds are substituted with a vinyl group. This substitution is characteristic exclusively to Juncaceae species. Juncusol ( 2 ) was isolated from every investigated species. The richest source of phenanthrenes, as well as the most extensively investigated species is J. effusus . Several isolated compounds possessed different biological activities, e.g. antiproliferative, antimicrobial, anti-inflammatory, antioxidant, spasmolytic, anxiolytic, and antialgal effects. Among them, dehydroeffusol ( 60 ) is the most promising one, as it showed antimicrobial, anxiolytic, sedative, spasmolytic, cellular protective and antiproliferative activities. The aim of this review is to summarize the occurrence of phenanthrenes in the family Juncaceae, and give a comprehensive overview of their isolation, structural characteristics and biological activities.

The demand for sustainable, low-cost, and high-performance natural cellulose foams with isotropic structures has increased greatly due to growing environmental awareness. However, the synthesis of current cellulose foams/aerogels requires substantial amounts of energy and chemicals, mainly due to the challenges posed by the poor solubility and processability of raw cellulose derived from biomass resources. Consequently, these challenges further highlight the advantages offered by the direct utilization of natural cellulose foams, considering their economic and environmental benefits. Previous studies on natural cellulose foams have predominantly focused on specific plant components such as phloem, xylem, vascular vessels, fruits, and seeds. In this study, we present an overlooked alternative: the aerenchyma tissue of aquatic or wetland plants. Specifically, we investigated on Juncus effusus L. (JE), a commonly found problematic wetland weed that is known for its high reproductive ability, causing a reduction in annual forage yield. The aerenchyma tissue of JE was discovered to possess a well-developed 3D interconnected hierarchical structure, exhibiting remarkable properties as a natural lignocellulosic foam. These properties include exceptional compressibility, hydrophobicity (water contact angle: 147°), lightweights (density: 0.017 g/cm3), and high porosity (98%). Through this study, we have introduced a novel natural cellulose foam and explored the utilization of biomass derived from wetland weed wastes.

Question: How multiple abiotic stress factors combined with herbivory affect interactions within plant communities is poorly understood. We ask how large herbivore grazing affects the direction of plant-plant interactions along an environmental gradient in a salt marsh. Location: Grazed (cattle) and ungrazed salt marshes of the Dutch Wadden Sea island Schiermonnikoog. Here, patches of tall plant communities, dominated by the tough, unpalatable species Juncus maritimus Lam., are found alternating with low-statured, intensively grazed plant communities. Methods: Along the inundation gradient, we measured plant species composition and plant species traits (specific leaf area, specific root length, maximum height and abundance) inside and outside J. maritimus patches in grazed and ungrazed areas. In addition, we measured soil structure parameters (bulk density, soil porosity, clay depth), multiple limiting conditions for plant growth (soil salinity, soil redox, plant canopy light interception), plant biomass, presence of herbivores and abundance of soil macro-detritivores. Results: Under grazing, the palatable grasses Elytrigia atherica (Link) Kerguélen and Festuca rubra L. were positively associated with J. maritimus, while shadeintolerant Puccinellia maritima (Huds.) Parl, and Juncus gerardii Loisel. were negatively associated with this species. Furthermore, macro-detriti vore presence was higher inside J. maritimus patches. In ungrazed areas E. atherica and F. rubra were negatively associated with J. maritimus, while P. maritima and J. gerardii were rare. In both grazed and ungrazed conditions the directions of species associations were independent of the inundation gradient. Analysis of species traits and abiotic conditions suggested that assodational resistance (a facilitation type) was important in grazed areas. In ungrazed areas, light competition was the likely dominant process. Conclusions: The direction of species associations within these salt marsh communities was strongly affected by grazing, not by the underlying stress gradient. Measurement of species traits indicated that plant-plant interactions shifted from competitive to facilitative under grazing. Besides grazing, cross-trophic facilitation of soil disturbing macro-detritivores may play an important-thus far ignored-role in structuring plant communities.

Background and aim The presence of chlorides in soils, e.g., from de-icing salts may change metal availability to plants. Methods To assess the role of de-icing chlorides on bioavailability of metals, the samples of the rhizosphere soils, roots and shoots of Juncus effusus L. were collected monthly from April to June of 2019 in the vicinity of roads and analyzed for trace (Ag, Cd, Co, Cu, Pb, Zn) and rare earth elements (from La to Lu). Results Concentrations of Cl − were distinctly higher in the shoots than in the roots. Apart from Cd, the concentration sequence of the other metals was as follows: rhizosphere soils>roots>shoots. The bioaccumulation and translocation factors indicated that Cd was the most preferably transported to the shoots as opposed to Ag, Co, Pb and REEs that showed a very low translocation potential. Negative correlations, which were noted between Cu and Co in the shoots and Cl − in soils, revealed their role in salinity stress alleviation. All soil samples showed a positive anomaly of Ce and a negative anomaly of Eu, whereas the shoots showed in turn a negative anomaly of Ce and a distinct positive anomaly of Eu. The lowest salinity factors (K/Na, Ca/Na) of the shoots resulted from an increase of salinity in J. effusus by higher sodium concentrations derived from de-icing NaCl. Conclusions De-icing agents may change the uptake of other elements. In natural habitats, the factors affecting this process include: type of element, soil metal concentrations and interactions, and individual plant features.

Juncus (Juncaceae) comprises over 300 species with high morphological plasticity, and its systematics remain incompletely resolved due to limited genomic resources. Here, we generated complete plastid genomes for two Korean Juncus species (J. decipiens and J. gracillimus) and incorporated plastid coding genes from an additional species to reconstruct phylogenetic relationships and examine plastome evolution within Juncaceae. Comparative analyses revealed substantial plastome size variation across Juncus and Luzula, largely driven by changes in inverted repeat (IR) length, with Luzula plastomes showing pronounced IR expansion. Within Juncus, extensive structural rearrangements were detected, including multiple inversion events, and closely related taxa shared conserved inversion patterns. Phylogenomic analyses recovered well-supported clades that were associated with structural traits such as extreme small single-copy (SSC) contraction and consistent loss of the plastid ndh, some rps and rpl gene families, indicating clade-specific plastome evolution in Juncaceae. To support applied molecular identification, we identified J. decipiens-specific plastid diagnostic SNPs (matK, rpl2) and validated allele-specific PCR markers using individuals from different species within the Juncus genus. In parallel, transcriptome sequencing of J. decipiens generated 133,559 transcripts and 66,324 unigenes, enabling discovery of high-confidence nuclear exonic SNP loci by mapping reads to a J. effusus nuclear genome. Collectively, our results provide new insights into plastome structural evolution and gene loss in Juncus and deliver validated plastid and nuclear markers for authentication and future conservation or utilisation studies on J. decipiens.

1. Competition and herbivory are ubiquitous processes known to interactively shape plant performance, distribution and community assembly. Likewise, plant genetic variation and associated trait differences can impact both plant—plant and plant—herbivore interactions individually, yet few studies have explored these interactions simultaneously. 2. Saltmarsh communities are an ideal system to study these questions, as they are dominated along the Atlantic and Gulf coasts of the United States by a foundation plant species, Spartina alterniflora, with high levels of genetically based trait variation. Furthermore, consumer pressure and plant competitors are known to influence both the distribution and production of Spartina. We manipulated Spartina genetic identity, neighbour identity (needlerush, Juncus roemerianus) and consumer presence (snail, Littoraria irrorata) in a 1-year field experiment in St. Joseph Bay, FL, to test how the strength and direction of neighbour and consumer interactions vary by plant genotype. 3. Consumer effects on Spartina were generally stronger and more variable than those of the plant neighbourhood, and these effects were generally consistent across Spartina genotypes. However, genotype-specific variation in morphology, phenology and palatability significantly influenced both consumer and neighbour responses to Spartina: the consumer Littoraria was more likely to climb palatable Spartina genotypes, and neighbouring Juncus had shorter stems in the presence of highly productive Spartina genotypes. 4. Synthesis. Our results add to the growing list of examples high-lighting the role of intraspecific variation in species interactions and suggest that variation in these interactions may promote the maintenance of plant genetic variation and community composition.

A developing trend in stormwater treatment and management is the use of green technologies. Plant biofilters have been gaining increasing use in support of green technology objectives. This technical note reports on the development and preliminary testing of a laboratory-scale plant biofilter prototype for ammonia removal using a South African native plant species (Juncus effusus). The prototype design was based on a conceptual model for nitrogen fixation, plant uptake, bacterial nitrification and soil sorption. Additionally, a plug compartment was incorporated into the design to simulate plug flow as part of the conceptual model. Biofilter models with and without inoculated bacteria were compared. Ammonia reduction, nitrite and nitrate formation were observed. Results showed that the inoculated plant biofilter performed best, with an average of 61% reduction in ammonia within the filter compared to 15% in the normal plant biofilter. The incorporation of a plug compartment aided in slowing down the ammonia infiltration rate, increasing the retention time, and allowing for nitrification to occur.