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1.
Am Nat ; 203(6): E188-E199, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38781531

RESUMEN

AbstractAn individual's access to mates (i.e., its "mating potential") can constrain its reproduction but may also influence its fitness through effects on offspring survival. For instance, mate proximity may correspond with relatedness and lead to inbreeding depression in offspring. While offspring production and survival might respond differently to mating potential, previous studies have not considered the simultaneous effects of mating potential on these fitness components. We investigated the relationship of mating potential with both production and survival of offspring in populations of a long-lived herbaceous perennial, Echinacea angustifolia. Across 7 years and 14 sites, we quantified the mating potential of maternal plants in 1,278 mating bouts and followed the offspring from these bouts over 8 years. We used aster models to evaluate the relationship of mating potential with the number of offspring that emerged and that were alive after 8 years. Seedling emergence increased with mating potential. Despite this, the number of offspring surviving after 8 years showed no relationship to mating potential. Our results support the broader conclusion that the effect of mating potential on fitness erodes over time because of demographic stochasticity at the maternal level.


Asunto(s)
Echinacea , Aptitud Genética , Reproducción , Echinacea/fisiología , Plantones/fisiología , Plantones/crecimiento & desarrollo
2.
Sci Rep ; 11(1): 17352, 2021 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-34462447

RESUMEN

Human-designed landscapes can host diverse pollinator communities, and the availability of floral resources is central to supporting insect biodiversity in highly modified environments. However, some urban landscapes have relatively few pollinator-attractive plant species and management in urban environments rarely considers the function of these plants in generating and supporting a stable ecological community. Evaluations of 25 cultivars within five commercially popular herbaceous perennial ornamental plant genera (Agastache, Echinacea, Nepeta, Rudbeckia, and Salvia) revealed variation in the total and proportional abundance of visitors attracted. These varieties supported multiple pollinator functional groups, however bees were the primary visitors to in this system. Cultivars were assessed according to their function within a plant-pollinator network. Comparisons of artificial networks created with the six most attractive and six least attractive cultivars demonstrated that a planting scheme using the most attractive cultivars would attract nearly four times as many bee species, including several specialists and rare species. Plant diversity in the landscape was correlated with abundance and diversity of pollinator visitors, demonstrating that community context shapes a plant's relative attractiveness to pollinators. We conclude that herbaceous perennial cultivars can support an abundance and diversity of pollinator visitors, however, planting schemes should take into consideration the effects of cultivar, landscape plant diversity, floral phenology, floral area, and contribution to a stable ecological community.


Asunto(s)
Agastache/fisiología , Abejas/fisiología , Biodiversidad , Echinacea/fisiología , Nepeta/fisiología , Polen/química , Polinización/fisiología , Rudbeckia/fisiología , Salvia/fisiología , Algoritmos , Animales , Abejas/genética , Ecología , Entomología , Flores , Plantas
3.
Proc Natl Acad Sci U S A ; 117(6): 3000-3005, 2020 02 11.
Artículo en Inglés | MEDLINE | ID: mdl-31988124

RESUMEN

Fire is an important determinant of habitat structure and biodiversity across ecosystems worldwide. In fire-dependent communities, similar to the North American prairie, fire suppression contributes to local plant extinctions. Yet the demographic mechanisms responsible for species loss have not been directly investigated. We conducted a 21-y longitudinal study of 778 individual plants of Echinacea angustifolia, a widespread perennial species with chronically limited mating opportunities, to explore how fire affects reproduction. In a large preserve, with management units on different burn schedules, we investigated Echinacea mating scenes, which quantify isolation from potential mates and overlap in the timing of flowering, to determine the extent to which fire influences the potential for sexual reproduction. We demonstrate that fire consistently increased mating opportunities by synchronizing reproductive effort. Each fire occurred during fall or spring and stimulated flowering in the subsequent summer, thus synchronizing reproduction among years and increasing the proximity of potential mates after a fire. Greater within-season flowering synchrony in postfire mating scenes further increased mating potential. The improved postfire mating scene enhanced reproduction by increasing pollination efficiency. Seed set in scenes postfire exceeded other scenes by 55%, and annual fecundity nearly doubled (88% increase). We predict the reproductive benefits of synchronized flowering after fire can alleviate mate-finding Allee effects, promote population growth, and forestall local extirpation in small populations of Echinacea and many other prairie species. Furthermore, the synchronization of flowering by burning may improve mating opportunities, reproduction, and the likelihood of persistence for many other plant species in fire-dependent habitats.


Asunto(s)
Flores , Pradera , Polinización/fisiología , Incendios Forestales , Echinacea/crecimiento & desarrollo , Echinacea/fisiología , Flores/crecimiento & desarrollo , Flores/fisiología , Aptitud Genética , Estudios Longitudinales , Dinámica Poblacional , Semillas/fisiología
4.
Am Nat ; 192(3): 379-388, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30125234

RESUMEN

The timing and synchrony of mating activity in a population may vary both within and among years. With the exception of masting species, in which reproductive activity fluctuates dramatically among years, mating synchrony is typically studied within years. However, opportunities to mate also vary among years in nonmasting iteroparous species. We demonstrate that studying only within-year flowering synchrony fails to accurately quantify variation in mating opportunity in an experimental population ([Formula: see text]) of a nonmasting species, Echinacea angustifolia. We quantified individuals' synchrony of flowering within and among years and partitioned the contribution of each measure to mean daily mating potential, the number of potential mates per individual per day, averaged over every day that it flowered during the 11-year study period. Individual within- and among-year synchrony displayed wide variation and were weakly correlated. In particular, among-year synchrony explained 39% more variation in mean daily mating potential than did within-year synchrony. Among-year synchrony could have underappreciated significance for mating dynamics in nonmasting species.


Asunto(s)
Echinacea/fisiología , Flores/fisiología , Reproducción
5.
Sci Rep ; 7(1): 16924, 2017 12 05.
Artículo en Inglés | MEDLINE | ID: mdl-29208923

RESUMEN

The influence of the interaction(s) between the medicinal plant Echinacea purpurea (L.) Moench and its endophytic communities on the production of alkamides is investigated. To mimic the in vivo conditions, we have set up an infection model of axenic in vitro E. purpurea plants inoculated with a pool of bacterial strains isolated from the E. purpurea stems and leaves. Here we show different alkamide levels between control (not-inoculated) and inoculated plants, suggesting that the alkamide biosynthesis may be modulated by the bacterial infection. Then, we have analysed the branched-chain amino acids (BCCA) decarboxylase gene (GenBank Accession #LT593930; the enzymatic source for the amine moiety formation of the alkamides) expression patterns. The expression profile shows a higher expression level in the inoculated E. purpurea tissues than in the control ones. These results suggest that the plant-endophyte interaction can influence plant secondary metabolism affecting the therapeutic properties of E. purpurea.


Asunto(s)
Echinacea/fisiología , Endófitos/fisiología , Metabolismo Secundario , Carboxiliasas/genética , Echinacea/genética , Echinacea/metabolismo , Regulación de la Expresión Génica de las Plantas , Germinación , Proteínas de Plantas/genética , Alcamidas Poliinsaturadas/metabolismo
6.
Ecology ; 96(7): 1877-86, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26378310

RESUMEN

Habitat fragmentation produces small, spatially isolated populations that promote inbreeding. Remnant populations often contain inbred and outbred individuals, but it is unclear how inbreeding relative to outbreeding affects the expression of functional traits and biotic interactions such as herbivory. We measured a suite of 12 functional traits and herbivore damage on three genotypic cross types in the prairie forb, Echinacea angustifolia: inbred, and outbred crosses resulting from matings within and between remnant populations. Inbreeding significantly affected the expression of all 12 functional traits that influence resource capture. Inbred individuals had consistently lower photosynthetic rates, water use efficiencies, specific leaf areas, and had higher trichome numbers, percent C, and percent N than outbred individuals. However, herbivore damage did not differ significantly among the cross types and was not correlated with other leaf functional traits. Leaf architecture and low physiological rates of the inbred compared to outbred individuals imply poorer capture or use of resources. Inbred plants also had lower survival and fitness relative to outbred plants. Our results show that inbreeding, a phenomenon predicted and observed to occur in fragmented populations, influences key functional traits such as plant structure, physiology and elemental composition. Because of their likely role in fitness of individuals and ecological dynamics plant functional traits can serve as a bridge between evolution and community or ecosystem ecology.


Asunto(s)
Echinacea/genética , Echinacea/fisiología , Variación Genética , Herbivoria , Animales , Demografía , Monitoreo del Ambiente
7.
Oecologia ; 179(3): 811-21, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26187241

RESUMEN

Plantings in residential neighborhoods can support wild pollinators. However, it is unknown how effectively wild pollinators maintain pollination services in small, urban gardens with diverse floral resources. We used a 'mobile garden' experimental design, whereby potted plants of cucumber, eggplant, and purple coneflower were brought to 30 residential yards in Chicago, IL, USA, to enable direct assessment of pollination services provided by wild pollinator communities. We measured fruit and seed set and investigated the effect of within-yard characteristics and adjacent floral resources on plant pollination. Increased pollinator visitation and taxonomic richness generally led to increases in fruit and seed set for all focal plants. Furthermore, fruit and seed set were correlated across the three species, suggesting that pollination services vary across the landscape in ways that are consistent among different plant species. Plant species varied in terms of which pollinator groups provided the most visits and benefit for pollination. Cucumber pollination was linked to visitation by small sweat bees (Lasioglossum spp.), whereas eggplant pollination was linked to visits by bumble bees. Purple coneflower was visited by the most diverse group of pollinators and, perhaps due to this phenomenon, was more effectively pollinated in florally-rich gardens. Our results demonstrate how a diversity of wild bees supports pollination of multiple plant species, highlighting the importance of pollinator conservation within cities. Non-crop resources should continue to be planted in urban gardens, as these resources have a neutral and potentially positive effect on crop pollination.


Asunto(s)
Abejas/fisiología , Ciudades , Polinización , Animales , Biodiversidad , Cucumis sativus/crecimiento & desarrollo , Cucumis sativus/fisiología , Echinacea/crecimiento & desarrollo , Echinacea/fisiología , Ecosistema , Frutas/crecimiento & desarrollo , Semillas/crecimiento & desarrollo , Semillas/fisiología , Solanum melongena/crecimiento & desarrollo , Solanum melongena/fisiología
8.
Zhong Yao Cai ; 38(12): 2468-72, 2015 Dec.
Artículo en Chino | MEDLINE | ID: mdl-27352527

RESUMEN

OBJECTIVE: To explore the salt tolerance of Echiancea purpurea and its mechanism. METHODS: Echiancea purpurea was used as test material in this study and six salinity levels (0, 30, 60, 90, 120 and 150 mmol/L NaCl) were set. Effects on seed germination and salt tolerance relevant physiological and biochemical indexes of Echiancea purpurea were studied. RESULTS: Salt stress suppressed the germination of Echiancea purpurea seeds, induced osmotic adjustment substances proline, soluble sugar and K+ to increase, and activities of POD and SOD to rise, and meanwhile resulted in accumulation of Na+ and decrease of K+/Na+. CONCLUSION: Echiancea purpurea can tolerant salt stress to a certain degree, but in case of high salt concentrations, severe salt injury would remarkably suppress the growth of Echinacea purpurea.


Asunto(s)
Echinacea/fisiología , Plantas Tolerantes a la Sal/fisiología , Plantas Medicinales/fisiología , Cloruro de Sodio/química , Estrés Fisiológico
9.
Am J Bot ; 101(1): 180-9, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24388964

RESUMEN

PREMISE OF THE STUDY: Although spatial distance is considered the primary factor in determining plant mating patterns, flowering time and synchrony are also likely to be important. METHODS: We quantified the relationships of both distance and flowering phenology to the probability of mating between individual plants. In an experimental plot, we followed daily flowering phenology in Echinacea angustifolia, a self-incompatible perennial pollinated by solitary bees. We assigned paternity to 832 of 927 seedlings from 37 maternal plants using 11 microsatellite loci. Potential pollen donors included the experiment plot's 202 flowering plants and a nearby plot's 19 flowering plants. For each maternal plant sampled, we examined the pollen pool by quantifying correlated paternity and the effective number of pollen donors. KEY RESULTS: Significantly more pollinations occurred between neighboring and synchronous plants than expected under random mating, with distance being more important than flowering synchrony. The distance pollen moved varied over the course of the season, with late flowering plants mating with more distant plants compared to early or peak flowering plants. All maternal plants had a diverse set of mates (mean number of effective pollen donors = 23.7), and the composition of the pollen pools overlapped little between maternal plants. CONCLUSION: Both distance and flowering synchrony influenced pollination patterns in E. angustifolia. Our results suggest that pollen movement between incompatible mates and flowering asynchrony could be contributing to the reduced seed set observed in small E. angustifolia remnants. However, we also found that individual plants receive pollen from a diverse group of pollen donors.


Asunto(s)
Echinacea/fisiología , Flores/fisiología , Modelos Lineales , Minnesota , Reproducción/fisiología , Factores de Tiempo
10.
J Econ Entomol ; 106(5): 2055-71, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24224247

RESUMEN

Inflorescences (heads or capitula) of the putative self-incompatible species, purple coneflower (Echinacea angustifolia (DC) Cronq. (Asteraceae)), were visited by insects representing the Coleoptera, Diptera, Hymenoptera, and Lepidoptera, in accordance with a generalist pollination syndrome. Measurement of the effectiveness of insect species as pollinators was accomplished by permitting solitary visits to receptive, central disc florets of virgin (previously bagged) heads. Four parameters were quantified: total stigmatic pollen load and proportion of pollen grains germinated, numbers of pollen tubes at style bases, and percentages of total receptive florets that had retracted (shrivelled) styles. Quantifying total and germinated pollen grains proved ineffective, partly owing to the tendency of self-pollen to initiate pollen tubes. The most effective pollinators were Apidae, especially bumble bees (Bombus spp.) and the European honey bee (Apis mellifera L.) (mean: 39 - 61% of styles retracted). Other noteworthy pollinators were cloudless sulfur butterflies (Phoebis sennae L.--Pieridae; mean 47% of style bases with pollen tubes), golden blister beetles (Epicauta ferruginea Say--Meloidae; 44%), and grasshopper bee flies (Systoechus vulgaris Loew--Bombyliidae; 22%). Sunflower leafcutter bees (Megachile pugnata Say) were less effective (4% of styles retracted). Promisingly, analysis of the proportion of retracted styles provided similar results to the established technique of pollen-tube quantification, but had the significant advantages of being completed more rapidly, without a microscope, and in the field. The quantitative technique of retracted-style analysis appears well suited for prompt measurement of inflorescence-visiting insects as pollinators of many asteraceans.


Asunto(s)
Agricultura/métodos , Botánica/métodos , Echinacea/fisiología , Insectos/fisiología , Polinización , Animales , Cadena Alimentaria , Germinación , Inflorescencia/fisiología , Microscopía Electrónica de Rastreo , Polen/fisiología , Tubo Polínico/fisiología , Reproducción , Saskatchewan
11.
Oecologia ; 165(4): 1007-15, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21053022

RESUMEN

Vertebrate herbivores as diverse as ungulates, geese, and rabbits preferentially feed on plants that have previously experienced herbivory. Here, we ask whether smaller grassland "cryptic consumers" such as voles (Microtus ochrogaster and M. pennsylvanicus) preferentially clip (cut stems for access to leaves or seeds) or avoid previously clipped individuals of two tallgrass prairie species (Desmanthus illinoensis and Echinacea purpurea) within a growing season. Further, we ask how these plants respond to repeated clipping within a growing season, and whether the effects of this herbivory last into the subsequent growing season. Voles preferentially clipped stems of D. illinoensis and E. purpurea plants that had been previously clipped. The exception was indiscriminant clipping of stems of E. purpurea late in the growing season when its achenes, a favorite vole food, ripened. For D. illinoensis, repeated clipping resulted in a 59% reduction in biomass, 42% lower ratio of reproductive to vegetative biomass, and 57% fewer seeds produced per plant compared with unclipped plants. These effects lasted into the following growing season in which plants were protected from voles. In contrast, the only effect of repeated clipping for E. purpurea was that the number of achenes per plant was substantially reduced by three episodes of clipping. This effect did not carry over to the next growing season. Such differences in D. illinoensis and E. purpurea response to repeated stem clipping by voles offer insights into how these small rodents can effect major changes in composition and dominance in grassland communities.


Asunto(s)
Asteraceae/fisiología , Ecosistema , Conducta Alimentaria/fisiología , Roedores/fisiología , Animales , Arvicolinae/crecimiento & desarrollo , Arvicolinae/fisiología , Asteraceae/clasificación , Asteraceae/crecimiento & desarrollo , Biomasa , Echinacea/crecimiento & desarrollo , Echinacea/fisiología , Preferencias Alimentarias , Dinámica Poblacional , Conejos , Estaciones del Año , Plantones/crecimiento & desarrollo , Plantones/fisiología
12.
Ecology ; 91(3): 733-42, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20426332

RESUMEN

Pollen limitation of plant reproduction occurs in many plant species, particularly those in fragmented habitat; however, causes of pollen limitation are often unknown. We investigated the relationship between pollen limitation and pollinator visitation in the purple coneflower, Echinacea angustifolia (Asteraceae), which grows in the extremely fragmented tall grass prairie of North America. Previous investigations showed that pollen limitation of E. angustifolia increases with plant isolation and decreases with population size. We observed insect visitation to E. angustifolia over two flowering seasons and estimated pollen limitation of observed plants, using seed set as a proxy measure in 2004 and persistence of receptive style rows in 2005. We analyzed spatial patterns of bee visitation and pollination at two spatial scales: individual isolation, as measured by the distance to their kth nearest flowering neighbors (k = 1 - 15), and population size. Our results indicate that E. angustifolia is pollinated by over 26 species of native bees, with 70-75% of visits by halictid bees. Surprisingly, in both years, bee visitation increased with isolation of individual plants and did not vary significantly with population size. As expected, plant isolation increased pollen limitation and lowered seed set. There was no effect of population size on seed set in 2004, and pollen limitation decreased nonsignificantly with population size in 2005. We conclude that pollen receipt limits reproduction in E. angustifolia, but pollinator visitation does not. Remarkably, isolated plants simultaneously have increased rates of pollinator visitation by pollinators and decreased reproduction. We discuss alternative explanations of pollen limitation that are consistent with this apparent discrepancy, including a decline in the availability of compatible conspecific pollen with increased plant isolation.


Asunto(s)
Echinacea/fisiología , Insectos/fisiología , Polen/fisiología , Polinización/fisiología , Animales , Ecosistema
13.
Evolution ; 64(3): 761-71, 2010 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-19817853

RESUMEN

Despite fundamental importance to population dynamics, mating system evolution, and conservation management, the fitness consequences of breeding patterns in natural settings are rarely directly and rigorously evaluated. We experimentally crossed Echinacea angustifolia, a widespread, perennial prairie plant undergoing radical changes in distribution and abundance due to habitat fragmentation. We quantified the effects of both biparental inbreeding and crossing between remnant populations on progeny survival and reproduction in the field over the first eight years. Lifetime fitness is notoriously difficult to assess particularly for iteroparous species because of the long sequence and episodic nature of selection events. Even with fitness data in hand, analysis is typically plagued by nonnormal distributions of overall fitness that violate the assumptions of the usual parametric statistical approaches. We applied aster modeling, which integrates the measurements of separate, sequential, nonnormally distributed annual fitness components, and estimated current biparental inbreeding depression at 68% in progeny of sibling-mating. The effect of between-remnant crossing on fitness was negligible. Given that relatedness among individuals in remnant populations is already high and dispersal very limited, inbreeding depression may profoundly affect future dynamics and persistence of these populations, as well as their genetic composition.


Asunto(s)
Echinacea/genética , Evolución Biológica , Echinacea/fisiología , Ecosistema , Aptitud Genética , Hibridación Genética , Endogamia , Factores de Tiempo
14.
Plant Cell Rep ; 26(9): 1481-90, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17483954

RESUMEN

The biochemical mechanisms underlying thidiazuron (TDZ)-induced regeneration in plant cells have not been clearly elucidated. Exposure of leaf explants of Echinacea purpurea to a medium containing TDZ results in undifferentiated cell proliferation and differentiated growth as mixed shoot organogenesis and somatic embryogenesis. The current studies were undertaken to determine the potential roles of auxin, indoleamines, and ion signaling in the dedifferentiation and redifferentiation of plant cells. E. purpurea leaf explants were found to contain auxin and the related indoleamine neurotransmitters, melatonin, and serotonin. The levels of these endogenous indoleamines were increased by exposure to TDZ associated with the induction of regeneration. The auxin-transport inhibitor 2,3,5-triiodobenzoic acid and auxin action inhibitor, p-chlorophenoxyisobutyric acid decreased the TDZ-induced regeneration but increased concentrations of endogenous serotonin and melatonin. As well, inhibitors of calcium and sodium transport significantly reduced TDZ-induced morphogenesis while increasing endogenous indoleamine content. These data indicate that TDZ-induced regeneration is the manifestation of a metabolic cascade that includes an initial signaling event, accumulation, and transport of endogenous plant signals such as auxin and melatonin, a system of secondary messengers, and a concurrent stress response.


Asunto(s)
Aminas/metabolismo , Echinacea/efectos de los fármacos , Echinacea/fisiología , Ácidos Indolacéticos/metabolismo , Indoles/metabolismo , Canales Iónicos/metabolismo , Compuestos de Fenilurea/farmacología , Regeneración/efectos de los fármacos , Tiadiazoles/farmacología , Ácido 3-piridinacarboxílico, 1,4-dihidro-2,6-dimetil-5-nitro-4-(2-(trifluorometil)fenil)-, Éster Metílico/farmacología , Ácido Clofíbrico/farmacología , Lidocaína/farmacología , Melatonina/metabolismo , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/metabolismo , Serotonina/metabolismo , Ácidos Triyodobenzoicos/farmacología
15.
Ann N Y Acad Sci ; 1095: 574-84, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17404071

RESUMEN

Cadmium (Cd(2+)) is an important industrial pollutant, although its mechanism of toxicity has not been completely clarified. Cd(2+) is toxic to a wide range of organs and tissues, however, the primary target organs of Cd(2+) toxicity are the liver and kidney. Echinacea purpurea stimulating one or another tread of the immune system stimulates the expression of immunoglobulins and interferons. The experiments were performed on white laboratory mice using intraperitoneal (i.p.) injections 0.05 LD(50) amount of CdCl(2) solution. Two groups of mice were injected by Echinacea purpurea liquid extract: one 0.05 LD(50) and the other 0.1 LD(50). In this article, the Cd(2+) distribution in internal organs, its effect on the mitotic and apoptotic activity of liver cells, as well as effects of Echinacea purpurea liquid extract on Cd(2+)-induced changes in mice were investigated. Cd(2+) concentration in mice blood, liver, and kidney was detected by atomic absorption spectroscopy. Long-term injections of extract of Echinacea purpurea combined with Cd(2+)Cl(2) leads to the significant increase of Cd(2+) concentration in blood and investigated organs of experimental mice. Mitotic and apoptotic activity of liver cells was expressed as the estimated number of mitotic and apoptotic liver cells in randomly selected reference areas in histological slide. Echinacea purpurea decreases the mitotic activity of liver cells induced by Cd(2+) and increases apoptotic activity of the liver cells.


Asunto(s)
Apoptosis/efectos de los fármacos , Cadmio/toxicidad , Echinacea , Hígado/efectos de los fármacos , Hígado/patología , Mitosis/efectos de los fármacos , Animales , Cadmio/sangre , Cadmio/metabolismo , Cloruro de Cadmio/sangre , Cloruro de Cadmio/metabolismo , Cloruro de Cadmio/toxicidad , Recuento de Células , Echinacea/química , Echinacea/fisiología , Inhibidores de Crecimiento/química , Inhibidores de Crecimiento/fisiología , Inyecciones Intraperitoneales , Riñón/efectos de los fármacos , Riñón/metabolismo , Riñón/patología , Hígado/metabolismo , Ratones , Extractos Vegetales/química , Extractos Vegetales/farmacología
16.
Ann N Y Acad Sci ; 1095: 585-92, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17404072

RESUMEN

Echinacea purpurea (L.) Moench (EP) has many beneficial features, especially strengthening the immune system. Cadmium (Cd) is a ubiquitous metal and cumulative poison that may cause liver and kidney damage and the formation of neoplasia. In this article, the changes in organs and metabolism, the accumulation of various levels of Cd in tissues, and the effects of EP liquid extract on Cd-induced changes in mice were investigated. Experiments were carried out on the white laboratory mice. Solution of different Cd and EP concentrations were given to drink and experiments were performed. The concentration of Cd in mice blood, liver, kidneys, heart, spleen, skeletal muscle was determined using an electrothermal graphite furnace atomic absorption spectrophotometer Perkin-Elmer/Zeeman 3030. Long time per os of extract of EP combined with Cd leads to a significant increase of Cd concentration in blood and investigated organs of experiment mice.


Asunto(s)
Cadmio/toxicidad , Echinacea , Animales , Cadmio/sangre , Relación Dosis-Respuesta a Droga , Echinacea/química , Echinacea/fisiología , Interleucina-1/biosíntesis , Interleucina-6/biosíntesis , Activación de Macrófagos/inmunología , Ratones , Especificidad de Órganos/genética , Especificidad de Órganos/inmunología , Extractos Vegetales/farmacología , Factor de Necrosis Tumoral alfa/biosíntesis
17.
Am Nat ; 169(3): 383-97, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17230399

RESUMEN

We used empirical and modeling approaches to examine effects of plant breeding systems on demographic responses to habitat fragmentation. Empirically, we investigated effects of local flowering plant density on pollination and of population size on mate availability in a common, self-incompatible purple coneflower, Echinacea angustifolia, growing in fragmented prairie habitat. Pollination and recruitment increased with weighted local density around individual flowering plants. This positive density dependence is an Allee effect. In addition, mean mate compatibility between pairs of plants increased with population size. Based on this empirical study, we developed an individual-based, spatially explicit demographic model that incorporates autosomal loci and an S locus. We simulated habitat fragmentation in populations identical except for their breeding system, self-incompatible (SI) or self-compatible (SC). Both populations suffered reduced reproduction in small patches because of scarcity of plants within pollination distance (potential mates) and inbreeding depression. But SI species experienced an additional, genetic contribution to the Allee effect (S-Allee effect) caused by allele loss at the S locus, which reduces mate availability, thereby decreasing reproduction. The strength of the S-Allee effect increases through time (i.e., patches age) because random genetic drift reduces S-allele richness. We investigate how patch aging influences extinction and discuss how the S-Allee effect influences communities in fragmented habitat.


Asunto(s)
Cruzamiento , Echinacea/genética , Ecosistema , Aptitud Genética , Variación Genética , Polinización , Autoincompatibilidad en las Plantas con Flores/genética , Simulación por Computador , Echinacea/fisiología , Extinción Biológica , Flujo Genético , Minnesota , Modelos Biológicos , Densidad de Población , Autofecundación , Autoincompatibilidad en las Plantas con Flores/fisiología
18.
Plant Cell Rep ; 26(1): 13-9, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16897009

RESUMEN

The goals of this study were to investigate thidiazuron (TDZ)-induced morphogenesis of Echinacea purpurea L. and to assess the possibility of developing a liquid-based protocol for rapid micropropagation. Callus development and root organogenesis were observed on leaf explants cultured on media containing 2,4-dicholorophenoxyacetic acid or dicamba, but no plantlets were regenerated. Addition of TDZ to the culture medium as the sole growth regulator resulted in the production of regenerable callus cultures. The highest rate of regeneration was observed for explants cultured on medium with TDZ at 2.5 microM or higher. Tissue derived from 1.0 microM TDZ treatments was used to initiate liquid cultures. All liquid treatments produced a similar number of regenerants but significantly more healthy plants were obtained from cultures grown in the presence of 0.1 and 1.0 microM TDZ. This TDZ-based micropropagation system is the first liquid, large-scale propagation protocol developed for the mass production of E. purpurea plants.


Asunto(s)
Echinacea/efectos de los fármacos , Compuestos de Fenilurea/farmacología , Regeneración/efectos de los fármacos , Tiadiazoles/farmacología , Ácido 2,4-Diclorofenoxiacético/farmacología , Medios de Cultivo , Dicamba/farmacología , Relación Dosis-Respuesta a Droga , Echinacea/fisiología , Herbicidas/farmacología , Hojas de la Planta/efectos de los fármacos , Hojas de la Planta/fisiología , Brotes de la Planta/efectos de los fármacos , Brotes de la Planta/fisiología , Técnicas de Cultivo de Tejidos/métodos
19.
Planta Med ; 72(13): 1207-15, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-17021999

RESUMEN

Alcohol tinctures prepared from aged Echinacea roots are typically taken for preventing or treating upper respiratory infections, as they are purported to stimulate immunity in this context. The effects of long-term (> 1 year) dry storage on the capabilities of Echinacea spp. roots from mature individuals to modulate cytokine production are unknown. Using an older human adult model of influenza vaccination, we collected peripheral blood mononuclear cells from subjects 6 months post-vaccination and stimulated them in vitro with the two Type A influenza viruses contained in the trivalent 2004-2005 vaccine with a 50 % alcohol tincture prepared from the roots of one of seven Echinacea species: E. angustifolia, E. pallida, E. paradoxa, E. purpurea, E. sanguinea, E. simulata, and E. tennesseensis. Before being processed into extracts, all roots had been stored under dry conditions for sixteen months. Cells were cultured for 48 hours; following incubation, supernatants were collected and assayed for interleukin-2, interleukin-10, and interferon-gamma production, cytokines important in the immune response to viral infection. Four species ( E. angustifolia, E. purpurea, E. simulata, E. tennesseensis) augmented IL-10 production, diminished IL-2 production, and had no effect on IFN-gamma production. Echinacea pallida suppressed production of all cytokines; E. paradoxa and E. sanguinea behaved similarly, although to a lesser extent. The results from these in vitro bioactivity assays indicate that dried Echinacea roots stored for sixteen months maintain cytokine-modulating capacities. Our data support and extend previous research and indicate that tinctures from different Echinacea species have different patterns of immune modulation; further, they indicate that certain species may be efficacious in the immune response to viral infection.


Asunto(s)
Citocinas/biosíntesis , Echinacea/química , Factores Inmunológicos/farmacología , Vacunas contra la Influenza , Anciano , Células Cultivadas , Almacenaje de Medicamentos , Echinacea/fisiología , Humanos , Factores Inmunológicos/química , Factores Inmunológicos/normas , Virus de la Influenza A/inmunología , Interferón gamma/biosíntesis , Interleucina-10/biosíntesis , Interleucina-2/biosíntesis , Extractos Vegetales/química , Extractos Vegetales/farmacología , Extractos Vegetales/normas , Raíces de Plantas/química , Raíces de Plantas/fisiología
20.
Methods Mol Biol ; 318: 211-7, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16673918

RESUMEN

A plant regeneration system from the isolated protoplasts of Echinacea purpurea L. using an alginate solid/liquid culture is described in the chapter. Viable protoplasts were isolated rom 100 mg of young leaves of 4-wk-old seedlings in an isolation mixture containing 1.0% cellulase Onozuka R-10, 0.5% pectinase, and 0.3 mol/L mannitol. After isolation and purification, the mesophyll protoplasts were embedded into 0.6% Na-alginate at the density 1 x 10(-5) mL and cultured in modified Murashige and Skoog (MS) culture medium supplemented with 0.3 mol/L sucrose, 2.5 micromol/L benzylaminopurine (BA), and 5.0 micromol/L 2,4-dichlorophenoxyacetic acid (2,4-D). The visible colonies were present after 4 wk of culture. The protoplast-derived clones were transferred onto gellan gum-solidified basal medium supplemented with 1.0 micromol/L BA and 2.0 micromol/L indole-3-butyric acid (IBA) and formed compact and green calli. Shoot development was achieved by subculturing the calli onto the same basal medium supplemented with 5.0 micromol/L BA and 2.0 micromol/L IBA. Further subculture onto basal medium resulted in the regeneration of complete plantlets.


Asunto(s)
Echinacea/crecimiento & desarrollo , Protoplastos/fisiología , Técnicas de Cultivo de Célula , División Celular , Echinacea/fisiología , Brotes de la Planta , Plantas Medicinales/crecimiento & desarrollo , Plantas Medicinales/fisiología , Protoplastos/citología , Regeneración/fisiología
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