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1.
BMC Plant Biol ; 24(1): 905, 2024 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-39350020

RESUMEN

BACKGROUND: Polymorphisms are common in nature, but they are rarely shared among closely related species. Polymorphisms could originate through convergence, ancestral polymorphism, or introgression. Although shared neutral genomic variation across species is commonplace, few examples of shared functional traits exist. The blue-orange petal color polymorphisms in two closely related species, Lysimachia monelli and L. arvensis were investigated with UV-vis reflectance spectra, flavonoid biochemistry, and transcriptome comparisons followed by climate niche analysis. RESULTS: Similar color morphs between species have nearly identical reflectance spectra, flavonoid biochemistry, and ABP gene expression patterns. Transcriptome comparisons reveal two orange-specific genes directly involved in both blue-orange color polymorphisms: DFR-2 specificity redirects flux from the malvidin to the pelargonidin while BZ1-2 stabilizes the pelargonidin with glucose, producing the orange pelargonidin 3-glucoside. Moreover, a reduction of F3'5'H expression in orange petals also favors pelargonidin production. The climate niches for each color morph are the same between the two species for three temperature characteristics but differ for four precipitation variables. CONCLUSIONS: The similarities in reflectance spectra, biochemistry, and ABP genes suggest that a single shift from blue-to-orange shared by both lineages is the most plausible explanation. Our evidence suggests that this persistent flower color polymorphism may represent an ancestrally polymorphic trait that has transcended speciation, yet future analyses are necessary to confidently reject the alternative hypotheses.


Asunto(s)
Flores , Polimorfismo Genético , Primulaceae , Flores/genética , Primulaceae/genética , Pigmentación/genética , Antocianinas/metabolismo , Antocianinas/genética , Color , Transcriptoma , Flavonoides/metabolismo , Especificidad de la Especie , Clima , Regulación de la Expresión Génica de las Plantas , Lysimachia
2.
Ecol Lett ; 26 Suppl 1: S47-S61, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37840020

RESUMEN

Plasticity-mediated changes in interaction dynamics and structure may scale up and affect the ecological network in which the plastic species are embedded. Despite their potential relevance for understanding the effects of plasticity on ecological communities, these effects have seldom been analysed. We argue here that, by boosting the magnitude of intra-individual phenotypic variation, plasticity may have three possible direct effects on the interactions that the plastic species maintains with other species in the community: may expand the interaction niche, may cause a shift from one interaction niche to another or may even cause the colonization of a new niche. The combined action of these three factors can scale to the community level and eventually expresses itself as a modification in the topology and functionality of the entire ecological network. We propose that this causal pathway can be more widespread than previously thought and may explain how interaction niches evolve quickly in response to rapid changes in environmental conditions. The implication of this idea is not solely eco-evolutionary but may also help to understand how ecological interactions rewire and evolve in response to global change.


Asunto(s)
Adaptación Fisiológica , Evolución Biológica
3.
New Phytol ; 233(3): 1479-1493, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34657297

RESUMEN

Many flowers exhibit phenotypic plasticity. By inducing the production of several phenotypes, plasticity may favour the rapid exploration of different regions of the floral morphospace. We investigated how plasticity drives Moricandia arvensis, a species displaying within-individual floral polyphenism, across the floral morphospace of the entire Brassicaceae family. We compiled the multidimensional floral phenotype, the phylogenetic relationships, and the pollination niche of over 3000 species to construct a family-wide floral morphospace. We assessed the disparity between the two M. arvensis floral morphs (as the distance between the phenotypic spaces occupied by each morph) and compared it with the family-wide disparity. We measured floral divergence by comparing disparity with the most common ancestor, and estimated the convergence of each floral morph with other species belonging to the same pollination niches. Moricandia arvensis exhibits a plasticity-mediated floral disparity greater than that found between species, genera and tribes. The novel phenotype of M. arvensis moves outside the region occupied by its ancestors and relatives, crosses into a new region where it encounters a different pollination niche, and converges with distant Brassicaceae lineages. Our study suggests that phenotypic plasticity favours floral divergence and rapid appearance of convergent flowers, a process which facilitates the evolution of generalist pollination systems.


Asunto(s)
Brassicaceae , Adaptación Fisiológica , Brassicaceae/genética , Flores/genética , Filogenia , Polinización
4.
BMC Plant Biol ; 19(1): 496, 2019 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-31726989

RESUMEN

BACKGROUND: Anthocyanins are the primary source of colour in flowers and also accumulate in vegetative tissues, where they have multiple protective roles traditionally attributed to early compounds of the metabolic pathway (flavonols, flavones, etc.). Petal-specific loss of anthocyanins in petals allows plants to escape from the negative pleiotropic effects of flavonoid and anthocyanins loss in vegetative organs, where they perform a plethora of essential functions. Herein, we investigate the degree of pleiotropy at the biochemical scale in a pink-white flower colour polymorphism in the shore campion, Silene littorea. We report the frequencies of pink and white individuals across 21 populations and underlying biochemical profiles of three flower colour variants: anthocyanins present in all tissues (pink petals), petal-specific loss of anthocyanins (white petals), and loss of anthocyanins in all tissues (white petals). RESULTS: Individuals lacking anthocyanins only in petals represent a stable polymorphism in two populations at the northern edge of the species range (mean frequency 8-21%). Whereas, individuals lacking anthocyanins in the whole plant were found across the species range, yet always at very low frequencies (< 1%). Biochemically, the flavonoids detected were anthocyanins and flavones; in pigmented individuals, concentrations of flavones were 14-56× higher than anthocyanins across tissues with differences of > 100× detected in leaves. Loss of anthocyanin pigmentation, either in petals or in the whole plant, does not influence the ability of these phenotypes to synthesize flavones, and this pattern was congruent among all sampled populations. CONCLUSIONS: We found that all colour variants showed similar flavone profiles, either in petals or in the whole plant, and only the flower colour variant with anthocyanins in photosynthetic tissues persists as a stable flower colour polymorphism. These findings suggest that anthocyanins in photosynthetic tissues, not flavonoid intermediates, are the targets of non-pollinator mediated selection.


Asunto(s)
Antocianinas/genética , Flores/genética , Silene/genética , Antocianinas/metabolismo , Cromatografía Líquida de Alta Presión , Flavonoides/metabolismo , Flores/metabolismo , Genes de Plantas , Pleiotropía Genética , Fenotipo , Pigmentación/genética , Polimorfismo Genético , Silene/metabolismo , Espectrometría de Masa por Ionización de Electrospray
5.
Ann Bot ; 116(2): 201-11, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26070638

RESUMEN

BACKGROUND AND AIMS: Evolution of autonomous selfing may be advantageous because it allows for reproductive assurance. In co-flowering plants competing for pollinators, the least common and/or attractive could suffer pollen limitations. Silene niceensis and S. ramosissima are taxonomically related species sharing the same habitat, although S. ramosissima is less abundant and has a more restricted distribution. They also have the same a priori nocturnal pollinator syndrome, and show an overlapping flowering phenology. The aim of this study was to investigate whether a selfing strategy in S. ramosissima allows it to avoid pollinator competition and/or interspecific pollen transfer with S. niceensis, which would thus enable both species to reach high levels of fruit and seed set. METHODS: The breeding system, petal colour, flower life span and degree of overlap between male and female phases, floral visitor abundance and visitation rates were analysed in two sympatric populations of S. niceensis and S. ramosissima in southern Spain. KEY RESULTS: Autonomous selfing in S. ramosissima produced very high fruit and seed set, which was also similar to open-pollinated plants. Silene niceensis showed minimum levels of autonomous selfing, and pollen/ovule ratios were within the range expected for the breeding system. In contrast to S. niceensis, flower life span was much shorter in S. ramosissima, and male and female organs completely overlapped in space and time. Upper surface petals of both species showed differing brightness, chroma and hue. Flowers of S. niceensis were actively visited by moths, hawkmoths and syrphids, whereas those of S. ramosissima were almost never visited. CONCLUSIONS: The findings show that different breeding strategies exist between the sympatric co-flowering S. niceensis and S. ramosissima, the former specializing in crepuscular-nocturnal pollination and the latter mainly based on autonomous selfing. These two strategies allow both species to share the restricted dune habitat in which they exist, with a high female reproductive success due to the absence of pollinator competition and/or interspecific pollen flow.


Asunto(s)
Insectos/fisiología , Polinización/fisiología , Autofecundación/fisiología , Silene/fisiología , Simpatría/fisiología , Animales , Modelos Lineales , Modelos Biológicos , Óvulo Vegetal/fisiología , Polen/fisiología , España
6.
Evol Lett ; 8(4): 610-621, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39100232

RESUMEN

Adaptive phenotypic plasticity evolves in response to the contrasting selection pressures that arise when organisms face environmental heterogeneity. Despite its importance for understanding how organisms successfully cope with environmental change, adaptive plasticity is often assumed but rarely demonstrated. We study here the adaptive nature of the extreme seasonal within-individual floral polyphenism exhibited by the crucifer Moricandia arvensis, a Mediterranean species that produces two different types of flowers depending on the season of the year. During spring, this species has large, cross-shaped, lilac flowers, while during summer, it develops small, rounded, white flowers. Although floral polyphenism was associated with increased plant fitness, selection moved floral traits away from their local optimum values during the harsh summer. This result strongly suggests that floral polyphenism is not adaptive in M. arvensis. The main factor selecting against floral polyphenism was pollinators, as they select for the same floral morph in all environments. Despite not being adaptive, floral polyphenism occurs throughout the entire distribution range of M. arvensis and has probably been present since the origin of the species. To solve this paradox, we explored the factors causing floral polyphenism, finding that floral polyphenism was triggered by summer flowering. Summer flowering was beneficial because it led to extra seed production and was favored by adaptive plasticity in leaf functional traits. Taken together, our study reveals a complex scenario in which nonadaptive floral polyphenism has been indirectly maintained over M. arvensis evolutionary history by selection operating to favor summer flowering. Our study provides thus strong evidence that nonadaptive plasticity may evolve as a byproduct of colonizing stressful environments.

7.
J Pediatr Gastroenterol Nutr ; 54(1): 55-61, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21873895

RESUMEN

OBJECTIVES: The aim of the study was to examine the effects of a follow-on formula containing Lactobacillus fermentum CECT5716 (L. fermentum) on the incidence of infections in infants between the ages of 6 and 12 months. PATIENTS AND METHODS: A randomized double-blinded controlled study including infants at the age of 6 months was conducted. Infants were assigned randomly to either follow-on formula supplemented with L. fermentum plus galactooligosaccharide (experimental group, EG), or the same formula supplemented with only galactooligosaccharide (control group, CG). The main outcome was the incidence of infections for the 6-month duration of the study. RESULTS: The EG showed a significant 46% reduction in the incidence rate (IR) of gastrointestinal infections (EG: 0.196 ±â€Š0.51, CG: 0.363 ±â€Š0.53, IR ratio 0.54, 95% confidence interval [CI] 0.307-0.950, P = 0.032), 27% reduction in the incidence of upper respiratory tract infections (EG: 0.969 ±â€Š0.96, CG: 1.330 ±â€Š1.23, IR ratio 0.729, 95% CI 0.46-1.38, P = 0.026), and 30% reduction in the total number of infections (EG: 1.464 ±â€Š1.15, CG: 2.077 ±â€Š1.59, IR ratio 0.70, 95% CI 0.46-1.38, P = 0.003), at the end of the study period compared with CG. CONCLUSIONS: Administration of a follow-on formula with L. fermentum CECT5716 may be useful for the prevention of community-acquired gastrointestinal and upper respiratory infections.


Asunto(s)
Microbiología de Alimentos , Enfermedades Gastrointestinales/prevención & control , Fórmulas Infantiles , Limosilactobacillus fermentum , Leche Humana/microbiología , Probióticos/uso terapéutico , Infecciones del Sistema Respiratorio/prevención & control , Suplementos Dietéticos , Método Doble Ciego , Femenino , Enfermedades Gastrointestinales/epidemiología , Humanos , Incidencia , Lactante , Fórmulas Infantiles/química , Masculino , Infecciones del Sistema Respiratorio/epidemiología
8.
J Perinat Med ; 39(2): 203-8, 2011 03.
Artículo en Inglés | MEDLINE | ID: mdl-21299358

RESUMEN

AIMS: To assess the relationship between clinically maternal chorioamnionitis and outcome in preterm very-low-birth weight (VLBW) infants. METHODS: An observational case-control study was conducted in the neonatology departments of 12 acute care teaching hospitals in Spain. Between January 2004 and December 2006, all consecutive VLBW (≤1500 g) infants who were born to a mother with clinical chorioamnionitis were enrolled. The controls included infants who were born to mothers without chorioamnionitis, matched by gestational age, and immediately born after each index case. At a corrected age of 24 months, a neurological examination and a psychological assessment of the surviving children were performed. RESULTS: Sixty-six of the newborn infants died; therefore, 262 infants from the original sample were available for the study. Follow-up data were obtained at a corrected age of 24 months from a total of 209 children (106 cases and 103 controls, 80% of the original sample size). Seventy children (33.5%) were diagnosed with some type of sequelae. The following conditions were all more prevalent in infants born to mothers with chorioamnionitis in comparison to controls: low development quotient (98.3±12.15 vs. 95.9±15.64; P=0.497), cerebral palsy (4.9% vs. 10.4%; P=0.138), seizures (1.0% vs. 3.8%; P=0.369), and other neurological or sensorial sequelae (32.0% vs. 34.9%; P=0.611). CONCLUSIONS: After controlling for gestational age, the study population demonstrated that the neurological outcomes in infants at a corrected age of 24 months was not worsened by chorioamnionitis.


Asunto(s)
Corioamnionitis/fisiopatología , Recién Nacido de muy Bajo Peso/fisiología , Estudios de Casos y Controles , Parálisis Cerebral/etiología , Desarrollo Infantil , Preescolar , Discapacidades del Desarrollo/etiología , Discapacidades del Desarrollo/psicología , Femenino , Estudios de Seguimiento , Humanos , Lactante , Recién Nacido , Masculino , Intercambio Materno-Fetal , Embarazo , Factores de Riesgo , Convulsiones/etiología
9.
Front Plant Sci ; 12: 617815, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33790921

RESUMEN

Variation in flower color due to transgenerational plasticity could stem directly from abiotic or biotic environmental conditions. Finding a link between biotic ecological interactions across generations and plasticity in flower color would indicate that transgenerational effects of ecological interactions, such as herbivory, might be involved in flower color evolution. We conducted controlled experiments across four generations of wild radish (Raphanus sativus, Brassicaceae) plants to explore whether flower color is influenced by herbivory, and to determine whether flower color is associated with transgenerational chromatin modifications. We found transgenerational effects of herbivory on flower color, partly related to chromatin modifications. Given the presence of herbivory in plant populations worldwide, our results are of broad significance and contribute to our understanding of flower color evolution.

10.
Front Plant Sci ; 12: 633979, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33692818

RESUMEN

Anthocyanins are the primary pigments contributing to the variety of flower colors among angiosperms and are considered essential for survival and reproduction. Anthocyanins are members of the flavonoids, a broader class of secondary metabolites, of which there are numerous structural genes and regulators thereof. In western European populations of Lysimachia arvensis, there are blue- and orange-petaled individuals. The proportion of blue-flowered plants increases with temperature and daylength yet decreases with precipitation. Here, we performed a transcriptome analysis to characterize the coding sequences of a large group of flavonoid biosynthetic genes, examine their expression and compare our results to flavonoid biochemical analysis for blue and orange petals. Among a set of 140 structural and regulatory genes broadly representing the flavonoid biosynthetic pathway, we found 39 genes with significant differential expression including some that have previously been reported to be involved in similar flower color transitions. In particular, F3'5'H and DFR, two genes at a critical branchpoint in the ABP for determining flower color, showed differential expression. The expression results were complemented by careful examination of the SNPs that differentiate the two color types for these two critical genes. The decreased expression of F3'5'H in orange petals and differential expression of two distinct copies of DFR, which also exhibit amino acid changes in the color-determining substrate specificity region, strongly correlate with the blue to orange transition. Our biochemical analysis was consistent with the transcriptome data indicating that the shift from blue to orange petals is caused by a change from primarily malvidin to largely pelargonidin forms of anthocyanins. Overall, we have identified several flavonoid biosynthetic pathway loci likely involved in the shift in flower color in L. arvensis and even more loci that may represent the complex network of genetic and physiological consequences of this flower color polymorphism.

11.
Ann Bot ; 106(2): 359-69, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20519239

RESUMEN

BACKGROUND AND AIMS: Monoecious plants have the capacity to allocate resources separately to male and female functions more easily than hermaphrodites. This can be advantageous against environmental stresses such as leaf herbivory. However, studies showing effects of herbivory on male and female functions and on the interaction with the plant's pollinators are limited, particularly in tropical plants. Here, the effects of experimental defoliation were examined in the monoecious shrub Croton suberosus (Euphorbiaceae), a wasp-pollinated species from a Mexican tropical dry forest. METHODS: Three defoliation treatments were applied: 0 % (control), 25 % (low) or 75 % (high) of plant leaf area removed. Vegetative (production of new leaves) and reproductive (pistillate and staminate flower production, pollen viability, nectar production, fruit set, and seed set) performance variables, and the abundance and activity of floral visitors were examined. KEY RESULTS: Defoliated plants overcompensated for tissue loss by producing more new leaves than control plants. Production of staminate flowers gradually decreased with increasing defoliation and the floral sex ratio (staminate : pistillate flowers) was drastically reduced in high-defoliation plants. In contrast, female reproductive performance (pistillate flower production, fruit set and seed set) and pollinator visitation and abundance were not impacted by defoliation. CONCLUSIONS: The asymmetrical effects of defoliation on male and female traits of C. suberosus may be due to the temporal and spatial flexibility in the allocation of resources deployed by monoecious plants. We posit that this helps to maintain the plant's pollination success in the face of leaf herbivory stress.


Asunto(s)
Euphorbiaceae/fisiología , Flores/fisiología , Hojas de la Planta/fisiología , Polinización/fisiología , Reproducción/fisiología
12.
Front Plant Sci ; 11: 588383, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33424884

RESUMEN

Flower color, as other floral traits, may suffer conflicting selective pressures mediated by both mutualists and antagonists. The maintenance of intraspecific flower color variability has been usually explained as a result of direct selection by biotic agents. However, flower color might also be under indirect selection through correlated traits, since correlations among flower traits are frequent. In this study, we aimed to find out how flower color variability is maintained in two nearby populations of Silene littorea that consistently differ in the proportions of white-flowered plants. To do that, we assessed natural selection on floral color and correlated traits by means of phenotypic selection analysis and path analysis. Strong directional selection on floral display and flower production was found in both populations through either male or female fitness. Flower color had a negative indirect effect on the total male and female fitness in Melide population, as plants with lighter corollas produced more flowers. In contrast, in Barra population, plants with darker corollas produced more flowers and have darker calices, which in turn were selected. Our results suggest that the prevalence of white-flowered plants in Melide and pink-flowered plants in Barra is a result of indirect selection through correlated flower traits and not a result of direct selection of either pollinators or herbivores on color.

13.
PLoS One ; 15(6): e0231611, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32555603

RESUMEN

Plants respond to changes in ultraviolet (UV) radiation both morphologically and physiologically. Among the variety of plant UV-responses, the synthesis of UV-absorbing flavonoids constitutes an effective non-enzymatic mechanism to mitigate photoinhibitory and photooxidative damage caused by UV stress, either reducing the penetration of incident UV radiation or acting as quenchers of reactive oxygen species (ROS). In this study, we designed a UV-exclusion experiment to investigate the effects of UV radiation in Silene littorea. We spectrophotometrically quantified concentrations of both anthocyanins and UV-absorbing phenolic compounds in petals, calyces, leaves and stems. Furthermore, we analyzed the UV effect on the photosynthetic activity in hours of maximum solar radiation and we tested the impact of UV radiation on male and female reproductive performance. We found that anthocyanin concentrations showed a significant decrease of about 20% with UV-exclusion in petals and stems, and a 30% decrease in calyces. The concentrations of UV-absorbing compounds under UV-exclusion decreased by approximately 25% in calyces and stems, and 12% in leaves. Photochemical efficiency of plants grown under UV decreased at maximum light stress, reaching an inhibition of 58% of photosynthetic activity, but their ability to recover after light-stress was not affected. In addition, exposure to UV radiation did not affect ovule production or seed set per flower, but decreased pollen production and total seed production per plant by 31% and 69%, respectively. Our results demonstrate that UV exposure produced opposing effects on the accumulation of plant phenolic compounds and reproduction. UV radiation increased the concentration of phenolic compounds, suggesting a photoprotective role of plant phenolics against UV light, yet overall reproduction was compromised.


Asunto(s)
Fenoles/análisis , Silene/química , Rayos Ultravioleta , Antocianinas/análisis , Antocianinas/metabolismo , Fenoles/metabolismo , Fotosíntesis/efectos de la radiación , Hojas de la Planta/química , Hojas de la Planta/metabolismo , Hojas de la Planta/efectos de la radiación , Tallos de la Planta/química , Tallos de la Planta/metabolismo , Tallos de la Planta/efectos de la radiación , Estaciones del Año , Semillas/química , Semillas/metabolismo , Silene/crecimiento & desarrollo , Silene/efectos de la radiación
14.
Nat Commun ; 11(1): 4019, 2020 08 11.
Artículo en Inglés | MEDLINE | ID: mdl-32782255

RESUMEN

Phenotypic plasticity, the ability of a genotype of producing different phenotypes when exposed to different environments, may impact ecological interactions. We study here how within-individual plasticity in Moricandia arvensis flowers modifies its pollination niche. During spring, this plant produces large, cross-shaped, UV-reflecting lilac flowers attracting mostly long-tongued large bees. However, unlike most co-occurring species, M. arvensis keeps flowering during the hot, dry summer due to its plasticity in key vegetative traits. Changes in temperature and photoperiod in summer trigger changes in gene expression and the production of small, rounded, UV-absorbing white flowers that attract a different assemblage of generalist pollinators. This shift in pollination niche potentially allows successful reproduction in harsh conditions, facilitating M. arvensis to face anthropogenic perturbations and climate change.


Asunto(s)
Adaptación Fisiológica , Ecosistema , Flores/fisiología , Polinización , Animales , Abejas , Brassicaceae/genética , Brassicaceae/fisiología , Flores/genética , Regulación de la Expresión Génica de las Plantas , Interacción Gen-Ambiente , Estaciones del Año
15.
Front Plant Sci ; 10: 1466, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31803208

RESUMEN

Reconstructing the phylogenetic relationships within Caryophyllaceae tribe Sileneae has been obscured by hybridization and incomplete lineage sorting. Silene is the largest genus in the Caryophyllaceae, and unraveling its evolutionary history has been particularly challenging. In order to infer the phylogenetic relationships among the five species in Silene section Psammophilae, we have performed a genome skimming approach to acquire the complete plastid genome (cpDNA), nuclear ribosomal cistron (nrDNA), and partial mitochondrial genome (mtDNA). We have included 26 populations, representing the range of each species' distribution. This section includes five morphologically similar species endemic to the Iberian Peninsula and Balearic Islands (Ibiza and Formentera), yet some of them occupy distinct edaphic habitats (e.g. maritime sands, calcareous sandstones). In addition to phylogeographic analyses, genetic structuring using the chloroplast data set was inferred with Discriminant Analysis of Principal Components (DAPC), analyses of molecular variance (AMOVA), and a partial Mantel test. Reference-guided assembly of 50 bp single-end and 250 bp paired-end Illumina reads produced the nearly complete cpDNA genome (154 kbp), partial mtDNA genome (from 81 to 114 kbp), and the nrDNA cistron (6.4 kbp). Selected variable regions of the cpDNA and mtDNA assemblies were confirmed by Sanger sequencing. Phylogenetic analyses of the mainland populations reveal incongruence among the three genomes. None of the three data sets produced relationships consistent with taxonomy or geography. In contrast, Silene cambessedesii, present in the Balearic Islands, is the only species that forms a strongly supported monophyletic clade in the cpDNA genome and is strongly differentiated with respect to the remaining taxa of the Iberian Peninsula. These results contrast with those obtained for mainland populations. Across the entire analysis, only one well-supported mainland clade of Silene littorea and Silene stockenii emerges from the southern region of the Iberian Peninsula. DAPC and AMOVA results suggest the absence of genetic structure among mainland populations of Silene section Psammophilae, whereas partial Mantel test discarded spatial correlation of genetic differentiation. The widespread incongruence between morphology-based taxonomic boundaries and phylogeography suggests a history of interspecific hybridization, in which only a substantial geographic barrier, like isolation by the Mediterranean Sea, was sufficient to create and maintain species boundaries in Silene section Psammophilae.

16.
Ann Bot ; 101(5): 717-26, 2008 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18250109

RESUMEN

BACKGROUND AND AIMS: In andromonoecious taxa with separate floral types along the inflorescence, architectural or plastic effects can simulate floral sexual dimorphism. Both the primary and secondary sexual characteristics of the cyathia of the protogynous andromonoecious species Euphorbia nicaeensis were analysed according to their sex and arrangement on the inflorescence. METHODS: The production of male and hermaphrodite cyathia at each inflorescence level was surveyed in two natural populations. The longevity, size, pollen production and viability, and nectar secretion of both types of cyathia were checked between inflorescence levels and between sexes at the only level at which they occur together. This sampling method makes it possible to know whether differences between cyathia types are based on sex or are attributable to inflorescence development. KEY RESULTS: Male cyathia were produced predominantly at the first and second inflorescence levels, whereas at levels 3-5, the cyathia were almost exclusively hermaphrodite. Viable pollen production by male cyathia at the second inflorescence level was higher than that of hermaphrodite cyathia at the third level but, when males and hermaphrodites at the same level were compared, their pollen production was similar. Male and hermaphrodite cyathia were similar in size, irrespective of the inflorescence level, although the exclusively hermaphrodite cyathia of the last level were smaller. Both cyathium types produced similar amounts of sugar. However, male cyathia produced nectar during their whole lifespans, whereas hermaphrodites produced it exclusively during their male phase. Moreover, the nectary activity of male cyathia started earlier in the day than that of hermaphrodites. CONCLUSIONS: An apparent floral dimorphism exists in the primary sexual characteristics of Euphorbia nicaeensis because differences in pollen production between cyathium types are due to theirs positions. Similarly, differences affecting most secondary sexual characteristics are only apparent between the two cyathium types. However, E. nicaeensis shows a true but slight floral dimorphism in some of the secondary sex characters related to nectar secretion. The lack of nectar production by the female phase of the hermaphrodite cyathia of E. nicaeensis indicates that this is a deceit-pollinated species.


Asunto(s)
Euphorbia/fisiología , Flores/fisiología , Reproducción/fisiología
17.
Ecol Evol ; 8(6): 3064-3076, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29607006

RESUMEN

Anthocyanin pigments have become a model trait for evolutionary ecology as they often provide adaptive benefits for plants. Anthocyanins have been traditionally quantified biochemically or more recently using spectral reflectance. However, both methods require destructive sampling and can be labor intensive and challenging with small samples. Recent advances in digital photography and image processing make it the method of choice for measuring color in the wild. Here, we use digital images as a quick, noninvasive method to estimate relative anthocyanin concentrations in species exhibiting color variation. Using a consumer-level digital camera and a free image processing toolbox, we extracted RGB values from digital images to generate color indices. We tested petals, stems, pedicels, and calyces of six species, which contain different types of anthocyanin pigments and exhibit different pigmentation patterns. Color indices were assessed by their correlation to biochemically determined anthocyanin concentrations. For comparison, we also calculated color indices from spectral reflectance and tested the correlation with anthocyanin concentration. Indices perform differently depending on the nature of the color variation. For both digital images and spectral reflectance, the most accurate estimates of anthocyanin concentration emerge from anthocyanin content-chroma ratio, anthocyanin content-chroma basic, and strength of green indices. Color indices derived from both digital images and spectral reflectance strongly correlate with biochemically determined anthocyanin concentration; however, the estimates from digital images performed better than spectral reflectance in terms of r2 and normalized root-mean-square error. This was particularly noticeable in a species with striped petals, but in the case of striped calyces, both methods showed a comparable relationship with anthocyanin concentration. Using digital images brings new opportunities to accurately quantify the anthocyanin concentrations in both floral and vegetative tissues. This method is efficient, completely noninvasive, applicable to both uniform and patterned color, and works with samples of any size.

18.
Biomedica ; 37(0): 104-111, 2017 Apr 01.
Artículo en Español | MEDLINE | ID: mdl-28527272

RESUMEN

INTRODUCTION: Glucocorticoids, widely used in the perinatal period, may be associated with adverse neurodevelopmental effects. OBJECTIVES: To analyze neurodevelopmental outcomes in a cohort of very low birth weight newborns treated with antenatal and/or postnatal corticosteroids. MATERIALS AND METHODS: This was a prospective cohort study in which we included all very low birth weight babies admitted to the neonatal intensive care unit of a tertiary hospital between 2008 and 2013. We compared the neurodevelopment among very low birth-weight newborns who did not receive prenatal corticosteroid therapy and those who received a complete course (two doses of 12 mg betamethasone) and an incomplete course (one dose), and between those who did not receive postnatal corticosteroid therapy and those who received it (systemic dexamethasone after the first week of life). Motor, neurosensory and cognitive functions, as well as behavior disorders during the first two years of age were evaluated. RESULTS: A total of 225 very low birth weight newborns were analyzed; 83.6% received prenatal corticosteroid therapy (24% incomplete treatment schedule and 59.6% complete schedule). Only 13.3% received systemic dexamethasone during the postnatal period. Neurological monitoring was performed corticosteroid therapy and more neurological disorders, and no significant differences were found among those who received complete and incomplete courses of prenatal corticosteroid therapy. CONCLUSION: These results did not demonstrate an association between perinatal corticosteroid therapy and worse neurodevelopmental outcomes in very low birth weight newborns.


Asunto(s)
Corticoesteroides/farmacología , Dexametasona/farmacología , Glucocorticoides/farmacología , Enfermedades del Prematuro/tratamiento farmacológico , Corticoesteroides/química , Dexametasona/química , Femenino , Glucocorticoides/química , Humanos , Recién Nacido , Embarazo , Estudios Prospectivos
19.
Nutr Hosp ; 34(5): 1067-1072, 2017 10 24.
Artículo en Inglés | MEDLINE | ID: mdl-29130703

RESUMEN

BACKGROUND: Significant efforts have been made to improve the nutritional support of very preterm infants. Large surveys may help to know the nutritional practices for preterm infants in neonatal units and identify if they are in line with the current guidelines. METHODS: A multicentre nationwide web-based survey on clinical feeding practices in very low birth weight (VLBW) infants was conducted in tertiary neonatal hospitals that admit infants with a birth weight < 1,500 g and/or a gestational age of < 32 weeks. RESULTS: The questionnaire was completed by 53 units (response rate, 59%). Over 90% of the units surveyed start amino-acid administration immediately after birth and more than half use novel intravenous fish oil-based lipid emulsions. Enteral nutrition is started within 24 hours of birth in 65% of units and 86% of these are medium-sized or large. Feeding volumes are increased at a rate of 10-30 ml/kg/day in > 90% of units. Monitoring of serum phosphorus was measured more frequently than albumin (p = 0.009) or triglycerides (p = 0.037), but only 28% of centres regularly measure pre-albumin as a nutritional biomarker. Human milk fortification and iron supplementation, starting at four weeks of age, are almost universal. However, only 30% of units administer 800 IU/day of vitamin D. Nearly 50% of the units discharge infants on preterm formula. CONCLUSION: Most Spanish neonatology units use early amino-acid supplementation and over half use novel fish oil-based lipid emulsions. Post-discharge nutrition practices and vitamin administration vary greatly.


Asunto(s)
Encuestas sobre Dietas , Recién Nacido de muy Bajo Peso , Aminoácidos/administración & dosificación , Aminoácidos/uso terapéutico , Nutrición Enteral , Emulsiones Grasas Intravenosas , Humanos , Lactante , Fenómenos Fisiológicos Nutricionales del Lactante , Recién Nacido , Leche Humana , España , Vitaminas/administración & dosificación , Vitaminas/uso terapéutico
20.
Free Radic Res ; 40(2): 199-206, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16390829

RESUMEN

Coenzyme Q10(CoQ10) in human milk at different stages of maturity in mothers of preterm and full-term infants and its relation to the total antioxidant capacity of milk is described for the first time. Thirty healthy breastfeeding women provided colostrum, transition-milk and mature-milk samples. Coenzyme Q, alpha-, gamma- and delta-tocopherol, fatty acids and the total antioxidant capacity of the milk were analyzed. Coenzyme Q10 was found at higher concentrations for colostrum (0.81+/-0.06 vs. 0.50+/-0.05 micromol/l) and transition milk (0.75+/-0.06 vs. 0.45+/-0.05 micromol/l) in the full-term vs. the preterm group (similar results were found for total antioxidant capacity). Concentrations of alpha- and gamma-tocopherol were higher in the full-term group and decreased with time. In conclusion, CoQ10 is present in breast milk, with higher concentration in mothers of full-term infants. CoQ10 in breast milk decreases through lactation in mothers delivering full-term infants. Also, CoQ10, alpha- and gamma-tocopherol concentration in human milk directly correlates with the antioxidant capacity of the milk.


Asunto(s)
Antioxidantes/metabolismo , Fenómenos Fisiológicos Nutricionales del Lactante/fisiología , Lactancia , Leche Humana/metabolismo , Ubiquinona/análogos & derivados , Adulto , Lactancia Materna , Coenzimas , Ácidos Grasos/metabolismo , Femenino , Humanos , Recién Nacido , Recien Nacido Prematuro , Madres , Embarazo , Tocoferoles/metabolismo , Ubiquinona/metabolismo , alfa-Tocoferol/metabolismo , gamma-Tocoferol/metabolismo
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