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1.
Sci Rep ; 12(1): 5270, 2022 03 28.
Artigo em Inglês | MEDLINE | ID: mdl-35347196

RESUMO

Purple loosestrife (Lythrum salicaria L.) is an invasive, herbaceous plant, frequently found in wetlands, creating monoculture stands, resulting in intensive management strategies in central New York, Ontario, and Quebec. The goal of this study was to identify the extent of infestations and to investigate factors that promote the spread of purple loosestrife. We attempted to answer several questions regarding level of infestation, connection to mowing, and influence of culverts. During flowering season in July and August, 2017-2019, we mapped infestations along 150 km (93 miles) of state highway between the Adirondack Park and the St. Lawrence River using the ESRI Collector app. The results of our preliminary analysis revealed significant increase in the number of plants (P < 0.001). In addition, a linear correlation analysis demonstrated a higher loosestrife density with an increase in plant species richness and a decrease in the distance to the closest infestation and wetland (P < 0.001 each). We found no statistical evidence that mowing promotes the spread of loosestrife. As expected, there were more individual infestations in highway ditches, but larger and denser infestations in wetlands (P = 0.003 in 2019). Culverts enable purple loosestrife to spread underneath highways and should be managed to prevent spread.


Assuntos
Lythrum , New York , Reprodução , Estações do Ano , Áreas Alagadas
2.
Oecologia ; 197(3): 715-727, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34716492

RESUMO

The ecological niche defines the favourable range of a species in a multidimensional space of ecological factors that determine the presence and function of individuals. This fundamental concept in ecology is widely used to understand plant species coexistence and segregation. In this study, we test for ecological differentiation among six annual Lythrum species that are characteristic of temporary pools in the South of France, where they either coexist or occur separately. We first analysed the co-occurrence of species at two different geographical scales: cluster analyses of species presence in 10 km grid cells and coexistence in 0.25 m2 quadrats within populations of each species. Second, for three to nine populations of each species, we quantified a range of biotic and abiotic parameters using point contacts and soil measurements in five 0.25 m2 quadrats per population. We performed PCA on all variables and analysed each variable separately to compare the ecological niche features of the six species. A phenological index was assessed for the plant community of each site. We detected highly localized niche differentiation in terms of soil pH (all species) and for a range of variables among pairs of species. The six species also showed marked differences in the flowering period relative to the mean and variability of flowering time in their local community. These fine-scaled niche differences are associated with phylogenetic distances among species and may contribute to species' coexistence. These results are integrated in a conservation management plan for the habitat of the rarest species in this group.


Assuntos
Lythrum , Diferenciação Celular , Ecossistema , Humanos , Filogenia , Solo
3.
Bull Environ Contam Toxicol ; 106(4): 575-582, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33528602

RESUMO

Decabromodiphenyl ether (BDE-209), a member of a major group of brominated flame retardants, is detected in aquatic environments at considerable levels and induces physiological and toxic effects on aquatic plants. In this study, the physiological responses induced by and the toxic effects of BDE-209 at different concentrations (0, 0.2, 0.5 and 1.0 mg L-1) in Lythrum salicaria were examined. OJIP transient curves indicated that BDE-209 treatment negatively affected photosystem II (PSII) grouping. Additionally, the results showed that BDE-209 inhibited seedling development and elevated reactive oxygen species (ROS), phosphorylated histone H2AX (γ-H2AX), malondialdehyde (MDA) levels and antioxidative enzyme activities in the roots and shoots of L. salicaria. The results revealed that BDE-209 exposure contributed to ROS accumulation, which was considered as the probable toxicity mechanism. The current results provided an insight into the development of L. salicaria with high BDE-209 tolerance.


Assuntos
Retardadores de Chama , Lythrum , Retardadores de Chama/toxicidade , Éteres Difenil Halogenados/toxicidade , Malondialdeído
4.
J Nat Prod ; 83(12): 3614-3622, 2020 12 24.
Artigo em Inglês | MEDLINE | ID: mdl-33270444

RESUMO

Lythrum salicaria herb (LSH) was applied in diarrhea therapy since ancient times. Despite empirically referenced therapeutic effects, the bioactivity mechanisms and chemical constituents responsible for pharmacological activity remain not fully resolved. Taking into consideration the historical use of LSH in treatment of diarrhea in humans and farm animals, the aim of the study was to examine in vitro the influence of LSH and its C-glycosylic ellagitannins on processes associated with maintaining intestinal epithelium integrity and enteropathogenic Escherichia coli (EPEC) growth and adhesion. LSH was not only inhibiting EPEC growth in a concentration dependent manner but also its adhesion to IPEC-J2 intestinal epithelial cell monolayers. Inhibitory activity toward EPEC growth was additionally confirmed ex vivo in distal colon samples of postweaning piglets. LSH and its dominating C-glycosylic ellagitannins, castalagin (1), vescalagin (2), and salicarinins A (3) and B (4) were stimulating IPEC-J2 monolayer formation by enhancing claudin 4 production. Parallelly tested gut microbiota metabolites of LSH ellagitannins, urolithin C (5), urolithin A (6), and its glucuronides (7) were inactive. The activities of LSH and the isolated ellagitannins support its purported antidiarrheal properties and indicate potential mechanisms responsible for its beneficial influence on the intestinal epithelium.


Assuntos
Aderência Bacteriana/efeitos dos fármacos , Escherichia coli Enteropatogênica/efeitos dos fármacos , Taninos Hidrolisáveis/farmacologia , Lythrum/química , Linhagem Celular , Escherichia coli Enteropatogênica/crescimento & desenvolvimento , Escherichia coli Enteropatogênica/fisiologia , Células Epiteliais/metabolismo , Microbioma Gastrointestinal/efeitos dos fármacos
5.
Biol Pharm Bull ; 43(11): 1767-1775, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33132322

RESUMO

Endotoxin is an unintentional contaminant that has numerous activities and can affect various biological experiments using cells. In this study, we measured the endotoxin activity of samples from a plant extract library (PEL) and determined their degrees of contamination. Endotoxin was detected in approx. 48% (n = 139) and approx. 4% (n = 5) of field-collected and crude drug samples, respectively, and in concentrations >5.0 EU/mL in some samples. The concentrations of endotoxin that affect cells in vitro vary depending on the target cell type. Although the degree of contamination varied in the present study, it was considered to have little effect on the cell experiments. More than 150 PEL samples had problems with reaction courses or recovery rates of Limulus amoebocyte lysate (LAL) tests. In the LAL tests, using three plant extracts [Sanguisorba officinalis L. (Rosaceae), Oenothera biennis L. (Onagraceae), and Lythrum salicaria L. (Lythraceae)], the polyphenolic compounds in the plant extracts affected LAL test and their effects differed depending on the plant species. When the 16 single polyphenol compounds were added to the LAL tests, the compounds with caffeoyl and pyrogallol moieties were found to affect the LAL reaction course and recovery rate. Furthermore, none of the compounds had any effects at concentrations of 1 µM. Because the plant extracts contained analogs of various polyphenolic compounds, they were presumed to actually act synergistically. Our findings demonstrated that attention must be paid to the recovery rate and reaction process of LAL tests with samples containing polyphenolic compounds.


Assuntos
Contaminação de Medicamentos/prevenção & controle , Endotoxinas/análise , Teste do Limulus/normas , Extratos Vegetais/química , Animais , Lythrum/química , Oenothera biennis/química , Extratos Vegetais/normas , Polifenóis/química , Sanguisorba/química
6.
J Ethnopharmacol ; 261: 113073, 2020 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-32673710

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Herb of purple loosestrife (Lythrum salicaria L. from Lythraceae family) (LSH) was used in Europe since ancient times till early-20th century in the therapy of diarrhea and dysentery in human and veterinary medicine. Post-weaning diarrhea is a main problem affecting global piglet production, which leads to significant economic losses because of increased morbidity and mortality, reduced average daily gain, and high antibiotic consumption. Post-weaning diarrhea has various causes, all of which have been linked to imbalances of intestinal microbiota. The aim of the present study was to determine the interaction of LSH with the gut microbiota of healthy post-weaning piglets in order to evaluate its influence on microbiota composition and metabolism as well as production of potentially bioactive postbiotic metabolites from the extract constituents. MATERIALS AND METHODS: Ex vivo anaerobic cultures of piglets intestinal microbiota obtained from jejunum, ileum, caecum and distal colon were conducted in various culture media supplemented with LSH. The production of postbiotic metabolites was determined using UPLC-DAD-MSn method. Bacterial genomic DNA was extracted and examined by sequencing by amplification of the 16S rDNA V3-V4 hypervariable regions followed by bioinformatic analysis. The production of SCFA in cultures was determined by GC analysis. RESULTS: Only the caecal and distal colon microbiota was able to hydrolyze and metabolize ellagitannins present in LSH to urolithins. Urolithin M6, M7, urolithin C, A and iso-urolithin A were detected together with a previously not described metabolite originating from the flavogalloyl moiety of C-glucosylic ellagitannins. LSH had no significant influence on microbiota diversity and metabolic activity, but was able to modulate its composition by significant decrease in Collinsella, Senegalimassilia, uncultured bacteria belonging to Porphyromonadaceae, Rikenellaceae RC9 gut group, Mogibacterium, Dorea, Lachnoclostridium, Lachnospiraceae UCG-004 group, Moryella, [Eubacterium] coprostanoligenes, Intestinimonas, Ruminococcaceae UCG-005, uncultured bacteria belonging to Ruminococcaceae, Acidaminococcus and Allisonella, while the relative abundance of Prevotella, Agathobacter, [Eubacterium] hallii group, Lachnospiraceae NK3A20 group, [Ruminococcus] torques group, Catenibacterium, Catenisphaera and Megasphaera increased. Significant correlations between taxa abundance and production of urolithins were determined. CONCLUSIONS: In the present study we have shown, that Lythrum salicaria herb fulfills the criteria of a potential candidate for antidiarrheal agent, which could be applied as therapy or prevention of post-weaning diarrhea in piglets. It not only modulates the gut microbiota composition without causing the dysbiosis and impairing metabolic activity, but is also a source of postbiotic metabolites, namely urolithins, which anti-inflammatory properties can be beneficial for gut health of piglets during the weaning period.


Assuntos
Antidiarreicos/farmacologia , Bactérias/efeitos dos fármacos , Ceco/microbiologia , Colo/microbiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Lythrum , Extratos Vegetais/farmacologia , Prebióticos , Animais , Animais Recém-Nascidos , Antidiarreicos/isolamento & purificação , Bactérias/metabolismo , Biotransformação , Cumarínicos/farmacologia , Lythrum/química , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/metabolismo , Sus scrofa , Desmame
7.
Med Sci Monit ; 26: e919360, 2020 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-32241963

RESUMO

BACKGROUND This study aimed to undertake a network pharmacology analysis to identify the active compounds of the herbal extract Christina Loosestrife, or Lysimachia Christinae (Jin Qian Cao), in the treatment of nephrolithiasis. MATERIAL AND METHODS The active components of Christina Loosestrife were identified from the Traditional Chinese Medicine Systems Pharmacology (TCMSP) database and analysis platform and the online Taiwan TCM database. The potentially active compounds were screened based on their parenteral bioavailability identified from the TCMSP database. The PharmMapper integrated pharmacophore matching platform was used for target identification of active compounds in nephrolithiasis. The identified active compounds were validated by molecular docking using the systemsDock network pharmacology website. Biological functions and pathway outcomes of effective targets were analyzed using the Metascape gene annotation resource. The results were used to construct the pharmacological networks, which were visualized and integrated using Cytoscape software. RESULTS There were 16 active compounds of Christina Loosestrife and 11 nephrolithiasis-associated targets that were obtained. Functional enrichment analysis showed that Christina Loosestrife might exert its therapeutic effects by regulating pathways that included purine salvage, interleukin-4 (IL-4) and IL-13 signaling, and neutrophil degranulation. CONCLUSIONS Network pharmacology analysis of the herbal extract, Christina Loosestrife, identified multiple active compounds, targets, and pathways involved in the effects on nephrolithiasis.


Assuntos
Medicamentos de Ervas Chinesas/farmacocinética , Cálculos Renais/tratamento farmacológico , Lythrum/química , Primulaceae/química , Disponibilidade Biológica , Medicamentos de Ervas Chinesas/uso terapêutico , Humanos , Medicina Tradicional Chinesa/métodos , Simulação de Acoplamento Molecular , Transdução de Sinais/efeitos dos fármacos , Resultado do Tratamento
8.
Mater Sci Eng C Mater Biol Appl ; 105: 110115, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31546384

RESUMO

This research has revealed the promising, green and one-pot approach for fabrication of antimicrobial nanohybrids based on organic nanofibers including cellulose (CNF), chitosan (CHNF), and lignocellulose (LCNF) nanofibers impregnated with silver nanoparticles (AgNPs). Lythrum salicaria extract was used as a reducing agent as well as a capping agent. Formation of the spherical AgNPs ranging between 45 and 65 nm was proved by UV-Vis spectroscopy, transmission electron microscopy (TEM), and dynamic light scattering (DLS). Biomaterials supported AgNPs were characterized and compared for their morphological, thermal, release, and antimicrobial properties. The considerable influence of the phenolic compounds of L.salicaria extract on the synthesis and uniform distribution of AgNPs on nanofibers was confirmed by field emission electron microscopy (FE-SEM). Energy dispersive X-ray spectroscopy (EDX) and ICP-OES analysis of nanohybrids, reflected a high loading capacity for LCNF and also CHNF in contrast to CNF. The release of AgNPs from LCNF substrate was lower than other nanofibers but the order of antimicrobial activity of nanohybrids against E.coli and S.aureus was as this: CHNF ˃ LCNF ˃ CNF. Generally, this research suggested that the efficiency of CHNF and LCNF as immobilizing support of AgNPs is higher than CNF and L.salicaria extract was proposed as a high potential reducing and capping agent.


Assuntos
Anti-Infecciosos/farmacologia , Liberação Controlada de Fármacos , Química Verde/métodos , Lythrum/química , Nanopartículas Metálicas/química , Nanofibras/química , Extratos Vegetais/química , Prata/química , Nanopartículas Metálicas/ultraestrutura , Nanofibras/ultraestrutura , Compostos Orgânicos/química , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Termogravimetria , Difração de Raios X
9.
Proc Biol Sci ; 286(1903): 20190603, 2019 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-31138075

RESUMO

Infectious diseases are a primary driver of bee decline worldwide, but limited understanding of how pathogens are transmitted hampers effective management. Flowers have been implicated as hubs of bee disease transmission, but we know little about how interspecific floral variation affects transmission dynamics. Using bumblebees ( Bombus impatiens), a trypanosomatid pathogen ( Crithidia bombi) and three plant species varying in floral morphology, we assessed how host infection and plant species affect pathogen deposition on flowers, and plant species and flower parts impact pathogen survival and acquisition at flowers. We found that host infection with Crithidia increased defaecation rates on flowers, and that bees deposited faeces onto bracts of Lobelia siphilitica and Lythrum salicaria more frequently than onto Monarda didyma bracts . Among flower parts, bracts were associated with the lowest pathogen survival but highest resulting infection intensity in bee hosts. Additionally, we found that Crithidia survival across flower parts was reduced with sun exposure. These results suggest that efficiency of pathogen transmission depends on where deposition occurs and the timing and place of acquisition, which varies among plant species and environmental conditions. This information could be used for development of wildflower mixes that maximize forage while minimizing disease spread.


Assuntos
Abelhas/fisiologia , Abelhas/parasitologia , Crithidia/fisiologia , Flores , Interações Hospedeiro-Parasita , Animais , Lobelia , Lythrum , Monarda
10.
Environ Sci Pollut Res Int ; 26(11): 10621-10630, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30762179

RESUMO

To investigate the effects of antibiotics on nitrogen removal and uptake by wetland plants, four typical macrophyte species, Cyperus alternifolius L., Typha angustifolia L., Lythrum salicaria L., and Acorus calamus L., were grown in hydroponic cultivation systems and fed wastewater polluted with 10 µg L-1 Ofloxacin (OFL) and Tetracycline (TET). Biomass production, nitrogen mass concentration, chlorophyll content, root exudates, and nitrogen removal efficiency of hydroponic cultivation were investigated. The results indicated that in all hydroponic systems, NH4+-N was entirely removed from the hydroponic substrate within 1 day and plant nitrogen accumulation was the main role of the removed NO3-. OFL and TET stimulated the accumulation of biomass and nitrogen of A. calamus but significantly inhibited the NO3--N removal ability of L. salicaria (98.6 to 76.2%) and T. augustifolia (84.3 to 40.2%). This indicates that A. calamus may be a good choice for nitrogen uptake in wetlands contaminated with antibiotics. OFL and TET improved the concentrations of total organic carbon (TOC), total nitrogen (TN), organic acid, and soluble sugars in root exudates, especially for oxalic acid. Considering the significant correlation between TOC of root exudates and nitrogen removal efficiency, the TOC of root exudates may be an important index for choosing macrophytes to maintain nitrogen removal ability in wetlands contaminated with antibiotics.


Assuntos
Acorus/efeitos dos fármacos , Antibacterianos/farmacologia , Cyperus/efeitos dos fármacos , Lythrum/efeitos dos fármacos , Nitrogênio/metabolismo , Typhaceae/efeitos dos fármacos , Acorus/crescimento & desenvolvimento , Acorus/metabolismo , Transporte Biológico/efeitos dos fármacos , Biomassa , Cyperus/crescimento & desenvolvimento , Cyperus/metabolismo , Hidroponia , Lythrum/crescimento & desenvolvimento , Lythrum/metabolismo , Nitrogênio/análise , Ofloxacino/análise , Ofloxacino/farmacologia , Typhaceae/crescimento & desenvolvimento , Typhaceae/metabolismo , Águas Residuárias/química , Poluentes da Água/análise , Poluentes da Água/farmacologia , Áreas Alagadas
11.
PLoS One ; 14(1): e0208300, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30605466

RESUMO

The aim of this project was to compare the phenotypic responses of global populations of Lythrum salicaria in cold/dry and hot/humid environments to determine if phenotypic plasticity varied between the native and invasive ranges, and secondarily if this variation was linked to genetic diversity. Common garden studies were conducted in Trebon, Czech Republic, and Lafayette, Louisiana, USA (cold/dry vs. hot/humid garden, respectively), using populations from latitudinal gradients in Eurasia and North America. Lythrum salicaria seeds collected from the same maternal plants across these latitudinal gradients were germinated and grown in Trebon and Lafayette. Tissue masses (above-, below-ground, inflorescence and total) of these individuals were assessed at the end of each growing season (2006-2008). Worldwide field measurements of L. salicaria height were made by volunteers from 2004-2016. Biomass and height data were analyzed using the General Linear Model framework and multivariate techniques. Molecular markers (amplified fragment length polymorphisms) of individuals used in the common garden study were analyzed using traditional genetic diversity metrics and Bayesian clustering algorithms in STRUCTURE. Reaction norms were developed from differences in maternal plant responses in Trebon versus Lafayette. In the common garden studies, stem/leaf, root and total biomass generally were highest for individuals grown from seeds collected in the southern part of the range in the cold garden, particularly by the third year of the study. In contrast, inflorescence biomass in the cold garden was higher by the third year in individuals from mid-latitude populations. As measured by volunteers, plants were taller in Eurasia than in North America moving from north to south with the pattern switching southward of 40°N latitude. Genetic diversity was similar between native and non-native invasive populations regardless of geographical origin of the seed and was not significantly different in the GLM Select model (p > 0.05). Reaction norm slopes showed that Eurasia had larger values than North America for reaction norms for above-ground and total biomass. Plants from the seeds of mother plants from Turkey had wide variation in total biomass when grown in Trebon versus Lafayette; this variation in response within certain populations may have contributed to the lack of population-level differences in plasticity. These results indicate no loss of genetic diversity for L. salicaria during its North American invasion, nor reduction in plastic tissue allocation responses to a varying environment, which may help explain some of its invasive qualities and which could be of adaptive value under changing future environments.


Assuntos
Temperatura Baixa , Jardinagem , Temperatura Alta , Lythrum/anatomia & histologia , Lythrum/genética , Análise de Variância , Biomassa , Germinação , Heterozigoto , Lythrum/crescimento & desenvolvimento , América do Norte , Sementes/crescimento & desenvolvimento , Áreas Alagadas
12.
Microbes Environ ; 33(4): 402-406, 2018 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-30404972

RESUMO

We herein described a new microbial isolation method using the interaction between the floating aquatic plant, duckweed, and microbes. We harvested microbial cells from Japanese loosestrife roots and co-cultivated these cells with aseptic duckweed using artificial inorganic medium for the plant for four weeks. During the co-cultivation, some duckweeds were collected every week, and the roots were used for microbial isolation using a low-nutrient plate medium. As a result, diverse microbial isolates, the compositions of which differed from those of the original source (Japanese loosestrife root), were obtained when the roots of duckweed were collected after 2 weeks of cultivation. We also successfully isolated a wide variety of novel microbes, including two strains within the rarely cultivated phylum, Armatimonadetes. The present study shows that a duckweed-microbe co-cultivation approach together with a conventional technique (direct isolation from a microbial source) effectively obtains more diverse microbes from a sole environmental sample.


Assuntos
Araceae/microbiologia , Bactérias/isolamento & purificação , Técnicas Bacteriológicas/métodos , Técnicas de Cocultura/métodos , Consórcios Microbianos , Bactérias/classificação , Bactérias/genética , Bactérias/crescimento & desenvolvimento , DNA Bacteriano/genética , Lythrum/microbiologia , Filogenia , Raízes de Plantas/microbiologia , RNA Ribossômico 16S/genética
13.
Artigo em Inglês | MEDLINE | ID: mdl-30455215

RESUMO

The potential use of herbarium specimens to detect herbivory trends is enormous but largely untapped. The objective of this study was to reconstruct the long-term herbivory pressure on the Eurasian invasive plant, purple loosestrife (Lythrum salicaria), by evaluating leaf damage over 1323 specimens from southern Québec (Canada). The hypothesis tested is that that the prevalence of herbivory damage on purple loosestrife is low during the invasion phase and increases throughout the saturation phase. Historical trends suggest a gradual increase in hole feeding and margin feeding damage from 1883 to around 1940, followed by a period of relative stability. The percentage of specimens with window feeding damage did not begin to increase until the end of the twentieth century, from 3% (2-6%) in 1990 to 45% (14-81%) in 2015. Temporal changes in the frequency of window feeding damage support the hypothesis of an increasing herbivory pressure by recently introduced insects. This study shows that leaf damage made by insects introduced for the biocontrol of purple loosestrife, such as coleopterans of the Neogalerucella genus, can be assessed from voucher specimens. Herbaria are a rich source in information that can be used to answer questions related to plant-insect interactions in the context of biological invasions and biodiversity changes.This article is part of the theme issue 'Biological collections for understanding biodiversity in the Anthropocene'.


Assuntos
Cadeia Alimentar , Herbivoria , Insetos/fisiologia , Lythrum/fisiologia , Manejo de Espécimes , Animais , Espécies Introduzidas , Museus , Folhas de Planta/fisiologia , Quebeque
14.
Water Sci Technol ; 77(3-4): 829-837, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29431728

RESUMO

In this study, the influence of vegetation type and environmental temperature on performance of constructed wetlands (CWs) was investigated. Results of vegetation types indicated that the removal of most nutrients in polyculture was greater than those in monoculture and unplanted control. The greatest removal percentages of NH4+-N, total nitrogen (TN) and total phosphorus (TP) in polyculture were 98.7%, 98.5%, and 92.6%, respectively. In experiments of different temperatures, the removal percentages of NH4+-N, NO3--N, TN and TP in all CWs tended to decrease with the decline of temperature. Especially, a sharp decline in the removal percentages of NO3--N (decreased by above 13.8%) and TN (decreased by above 7.9%) of all CWs was observed at low temperature (average temperature of 8.9 °C). Overall, the performance of CWs was obviously influenced by temperature, and the polyculture still showed best performance in the removal of nitrogen when the average temperature dropped to 19.8 °C. Additionally, the variations of urease activities in rhizosphere soil tended to decrease with the decreasing temperature. Overall, a substantial enhancement for nitrogen and TP removal in polyculture (Canna indica + Lythrum salicaria) was observed. In conclusion, CW cultivated with polyculture was a good strategy for enhancing nutrient removal when temperature was above 19.8 °C.


Assuntos
Lythrum/metabolismo , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/metabolismo , Áreas Alagadas , Zingiberales/metabolismo , Compostos de Amônio/metabolismo , Biodegradação Ambiental , Nitrogênio/metabolismo , Fósforo/metabolismo , Temperatura
15.
Am J Bot ; 104(4): 616-626, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28428199

RESUMO

PREMISE OF THE STUDY: Darwin proposed that the reciprocal arrangement of anthers and stigmas in heterostylous plants promotes cross-pollination through pollen segregation on pollinators' bodies. The floral tube in most heterostylous species constrains the feeding posture of pollinators determining the site of contact with sex organs located at different heights within a flower. Here, we evaluate Darwin's hypothesis in tristylous Lythrum salicaria, a species with a partially tubular corolla, and examine the extent to which the location of sex organs within a flower influence compatible and incompatible pollination. We predicted that the proficiency of cross-pollination would increase for more inserted sex organs due to the restrictions imposed by the floral tube on pollinator positioning. METHODS: We used experimental trimorphic and monomorphic arrays and emasculated flowers to quantify intermorph pollen transfer and capture among all sex-organ heights, and estimated the contribution of intraflower self-pollination, geitonogamous self-pollination, and intramorph outcross pollination to total intramorph pollination. KEY RESULTS: As predicted, disassortative pollination varied significantly with sex-organ height and was highest for short-level organs and lowest for long-level organs. In monomorphic arrays, most intramorph pollination resulted from outcross pollination followed by intraflower and geitonogamous self-pollination. CONCLUSIONS: Our results provide evidence for the Darwinian hypothesis. Reciprocal herkogamy promoted varying degrees of disassortative pollination with the magnitude strongly influenced by sex-organ height within a flower.


Assuntos
Flores/anatomia & histologia , Lythrum/anatomia & histologia , Polinização , Animais , Flores/fisiologia , Insetos , Lythrum/fisiologia , Modelos Biológicos , Polinização/fisiologia
16.
Ann Bot ; 119(8): 1295-1303, 2017 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-28369263

RESUMO

Background and Aims: The study of the evolution of floral traits has generally focused on pollination as the primary driver of selection. However, herbivores can also impose selection on floral traits through a variety of mechanisms, including florivory and parasitism. Less well understood is whether floral and inflorescence architecture traits that influence a plant's tolerance to herbivory, such as compensatory regrowth, alter pollinator-mediated selection. Methods: Because herbivore damage to Lythrum salicaria meristems typically leads to an increase in the number of inflorescences and the size of the floral display, an experiment was conducted to test whether simulated herbivory (i.e. clipping the developing meristem) could alter the magnitude or direction of pollinator-mediated selection on a suite of floral and inflorescence architecture traits. Using a pollen supplementation protocol, pollen limitation was compared in the presence and absence of meristem damage in order to quantify any interaction between pollinator and herbivore-mediated selection on floral traits. Key Results: Surprisingly, in spite of an obvious impact on floral display and architecture, with clipped plants producing more inflorescences and more flowers, there was no difference in pollen limitation between clipped and unclipped plants. Correspondingly, there was no evidence that imposing herbivore damage altered pollinator-mediated selection in this system. Rather, the herbivory treatment alone was found to alter direct selection on floral display, with clipped plants experiencing greater selection for earlier flowering and weaker selection for number of inflorescences when compared with unclipped plants. Conclusions: These findings imply that herbivory on its own can drive selection on plant floral traits and inflorescence architecture in this species, even more so than pollinators. Specifically, herbivory can impose selection on floral traits if such traits influence a plant's tolerance to herbivory, such as through the timing of flowering and/or the compensatory regrowth response.


Assuntos
Flores/anatomia & histologia , Herbivoria , Inflorescência/anatomia & histologia , Lythrum/genética , Seleção Genética , Lythrum/anatomia & histologia , Polinização
17.
J Evol Biol ; 30(5): 1042-1052, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28370749

RESUMO

We present evidence that populations of an invasive plant species that have become re-associated with a specialist herbivore in the exotic range through biological control have rapidly evolved increased antiherbivore defences compared to populations not exposed to biocontrol. We grew half-sib families of the invasive plant Lythrum salicaria sourced from 17 populations near Ottawa, Canada, that differed in their history of exposure to a biocontrol agent, the specialist beetle Neogalerucella calmariensis. In a glasshouse experiment, we manipulated larval and adult herbivory to examine whether a population's history of biocontrol influenced plant defence and growth. Plants sourced from populations with a history of biocontrol suffered lower defoliation than naïve, previously unexposed populations, strongly suggesting they had evolved higher resistance. Plants from biocontrol-exposed populations were also larger and produced more branches in response to herbivory, regrew faster even in the absence of herbivory and were better at compensating for the impacts of herbivory on growth (i.e. they exhibited increased tolerance). Furthermore, resistance and tolerance were positively correlated among genotypes with a history of biocontrol but not among naïve genotypes. Our findings suggest that biocontrol can rapidly select for increased defences in an invasive plant and may favour a mixed defence strategy of resistance and tolerance without an obvious cost to plant vigour. Although rarely studied, such evolutionary responses in the target species have important implications for the long-term efficacy of biocontrol programmes.


Assuntos
Evolução Biológica , Herbivoria , Espécies Introduzidas , Lythrum , Animais , Plantas
18.
Artigo em Inglês | MEDLINE | ID: mdl-27920377

RESUMO

Warmer and drier climates have shifted phenologies of many species. However, the magnitude and direction of phenological shifts vary widely among taxa, and it is often unclear when shifts are adaptive or how they affect long-term viability. Here, we model evolution of flowering phenology based on our long-term research of two species exhibiting opposite shifts in floral phenology: Lythrum salicaria, which is invasive in North America, and the sparse Rocky Mountain native Boechera stricta Genetic constraints are similar in both species, but differences in the timing of environmental conditions that favour growth lead to opposite phenological shifts under climate change. As temperatures increase, selection is predicted to favour earlier flowering in native B. stricta while reducing population viability, even if populations adapt rapidly to changing environmental conditions. By contrast, warming is predicted to favour delayed flowering in both native and introduced L. salicaria populations while increasing long-term viability. Relaxed selection from natural enemies in invasive L. salicaria is predicted to have little effect on flowering time but a large effect on reproductive fitness. Our approach highlights the importance of understanding ecological and genetic constraints to predict the ecological consequences of evolutionary responses to climate change on contemporary timescales.This article is part of the themed issue 'Human influences on evolution, and the ecological and societal consequences'.


Assuntos
Brassicaceae/crescimento & desenvolvimento , Mudança Climática , Flores/crescimento & desenvolvimento , Lythrum/crescimento & desenvolvimento , Reprodução , Evolução Biológica , Brassicaceae/genética , Espécies Introduzidas , Lythrum/genética , Modelos Biológicos , Modelos Genéticos , América do Norte
19.
J Nat Prod ; 79(12): 3022-3030, 2016 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-28006907

RESUMO

Ellagitannin-rich plant materials are used as popular remedies in the treatment of various inflammatory diseases. Urolithins are gut microbiota metabolites of ellagitannins and are considered responsible for in vivo health effects. Various natural products have been studied that are known sources of urolithins. However, few studies have focused on the metabolism of ellagitannin molecules. The aim of the study was to examine the metabolic fate of select ellagitannins using ex vivo cultures of human gut microbiota. Fifteen monomeric and dimeric ellagitannins, 1-O-galloyl-4,6-(S)-HHDP-ß-d-glucose (2), pedunculagin (3), potentillin (4), casuarictin (5), coriariin B (6), vescalagin (7), castalagin (8), stachyurin (9), casuarinin (10), stenophyllinin A (11), stenophyllanin A (12), salicarinin A (13), gemin A (14), agrimoniin (15), and oenothein B (16), and ellagic acid (1) were studied. The formation of the metabolites in ex vivo human microbiota cultures was monitored using UHPLC-DAD-MS/MS. Ellagitannins possessing hexahydroxydiphenoyl moieties were metabolized to 6H-dibenzo[b,d]pyran-6-one derivatives, i.e., urolithins. The observed differences in amounts of produced urolithins indicated that the individual microbiota composition and type of ingested ellagitannins could determine the rate of urolithin production. When the oral ingestion of natural products containing ellagitannins with hexahydroxydiphenoyl groups is considered, the formation of urolithins and their bioactivity should be addressed.


Assuntos
Microbioma Gastrointestinal , Taninos Hidrolisáveis/metabolismo , Fezes/microbiologia , Humanos , Taninos Hidrolisáveis/química , Lythrum/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular
20.
Mycologia ; 108(4): 625-37, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27091387

RESUMO

Fungal endophytes are one of several groups of heterotrophic organisms that associate with living plants. The net effects of these groups of organisms on each other and ultimately on their host plants depend in part on how they facilitate or antagonize one another. In this study we quantified the associations between endophyte communities and herbivory induced by a biological control in the invasive Lythrum salicaria at various spatial scales using a culture-based approach. We found positive associations between herbivory damage and endophyte isolation frequency and richness at the site level and weak, positive associations at the leaf level. Herbivory damage was more strongly influenced by processes at the site level than were endophyte isolation frequency and community structure, which were influenced by processes at the plant and leaf levels. Furthermore, endophytic taxa found in low herbivory sites were nested subsets of those taxa found at high herbivory sites. Our findings suggest that endophyte communities of L. salicaria are associated with, and potentially facilitated by, biocontrol-induced herbivory. Quantifying the associations between heterotrophic groups ultimately may lead to a clearer understanding of their complex interactions with plants.


Assuntos
Ração Animal/microbiologia , Endófitos/classificação , Endófitos/fisiologia , Herbivoria , Lythrum/microbiologia , Biodiversidade , Geografia , Folhas de Planta/microbiologia
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