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1.
An Acad Bras Cienc ; 96(2): e20230007, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38808873

RESUMEN

This study aimed to recognize the biogeographic patterns, richness, and diversity levels of the Brazilian endemic genus Orthophytum and identify their biotic components through a parsimony analysis of endemicity (PAE), to better understand the evolutionary history of this group and develop strategies for the conservation of its species. We prepared a database for the 54 currently known species of Orthophytum, including their geographical locations as obtained from digital databases of the principal herbaria of Brazil, Europe, and the USA. A parsimony analysis of endemicity (PAE) was used to delimit the areas of endemism based on two grids' sizes (1º x 1º and 2º × 2º). The majority rule consensus tree resulting from the PAE indicated three areas of endemism with high bootstrap, diversity, and richness indices: the northern portion of the Espinhaço Range, the southern portion of the Espinhaço Range, and the central portion of the Atlantic Forest. The recognition of those distribution patterns reveals a high number of microendemic species, which is discussed here.


Asunto(s)
Biodiversidad , Bromeliaceae , Brasil , Bromeliaceae/clasificación
2.
BMC Plant Biol ; 20(1): 111, 2020 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-32164546

RESUMEN

BACKGROUND: The angiosperm family Bromeliaceae comprises over 3.500 species characterized by exceptionally high morphological and ecological diversity, but a very low genetic variation. In many genera, plants are vegetatively very similar which makes determination of non flowering bromeliads difficult. This is particularly problematic with living collections where plants are often cultivated over decades without flowering. DNA barcoding is therefore a very promising approach to provide reliable and convenient assistance in species determination. However, the observed low genetic variation of canonical barcoding markers in bromeliads causes problems. RESULT: In this study the low-copy nuclear gene Agt1 is identified as a novel DNA barcoding marker suitable for molecular identification of closely related bromeliad species. Combining a comparatively slowly evolving exon sequence with an adjacent, genetically highly variable intron, correctly matching MegaBLAST based species identification rate was found to be approximately double the highest rate yet reported for bromeliads using other barcode markers. CONCLUSION: In the present work, we characterize Agt1 as a novel plant DNA barcoding marker to be used for barcoding of bromeliads, a plant group with low genetic variation. Moreover, we provide a comprehensive marker sequence dataset for further use in the bromeliad research community.


Asunto(s)
Bromeliaceae/genética , Código de Barras del ADN Taxonómico , ADN de Plantas/genética , Proteínas de Plantas/genética , Bromeliaceae/clasificación
3.
Mol Biol Rep ; 47(1): 179-189, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31587186

RESUMEN

Plant species of various families, such as those of Bromeliaceae, occur on inselbergs where they are subject to geographic isolation and environmental conditions that can lead to genetic erosion. This, in turn, can result in the loss of natural populations due to homozygosis, or changes in ploidy that may lead to reproductive isolation. The genetic diversity of five natural populations of Pitcairnia azouryi was measured using nine microsatellite markers transferred from P. albiflos and P. geyskesii. Chromosome numbers and nuclear DNA content were also evaluated. The results indicated moderate genetic differentiation among populations (FST = 0.188), and significant gene flow (Nm = 1.073) in four of the five populations. P. azouryi has, predominantly, 2n = 50 chromosomes and DNA content of 2C = 1.16 pg, but the tetraploid condition was found (2n = 100 and 2C = 2.32 pg) in seedlings of an individual of the most geographically isolated population. The moderate level of genetic structuring observed for P. azouryi seems to be related to its disjoint geographical distribution and the locally aggregated spatial structure of the populations, which are isolated from each other, hindering the inter and intrapopulational gene flow. This interpretation was also evidenced by the mantel test (r = 0.777, P < 0.05). The occurrence of diploid individuals with tetraploid seedlings is indicative of events of eupolyploidization, possibly due to the environmental conditions of this geographically isolated population.


Asunto(s)
Bromeliaceae/genética , Especies en Peligro de Extinción , Bosques , Variación Genética , Océano Atlántico , Brasil , Bromeliaceae/clasificación , Flujo Génico , Genética de Población , Genotipo , Geografía , Cariotipo , Cariotipificación/métodos , Repeticiones de Microsatélite/genética
4.
Plant Physiol ; 178(1): 148-162, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30042212

RESUMEN

The leaf intercellular airspace (IAS) is generally considered to have high conductance to CO2 diffusion relative to the liquid phase. While previous studies accounted for leaf-level variation in porosity and mesophyll thickness, they omitted 3D IAS traits that potentially influence IAS conductance (gIAS). Here, we reevaluated the standard equation for gIAS by incorporating tortuosity, lateral path lengthening, and IAS connectivity. We measured and spatially mapped these geometric IAS traits for 19 Bromeliaceae species with Crassulacean acid metabolism (CAM) or C3 photosynthetic pathways using x-ray microcomputed tomography imaging and a novel computational approach. We found substantial variation in porosity (0.04-0.73 m3 m-3), tortuosity (1.09-3.33 m2 m-2), lateral path lengthening (1.12-3.19 m m-1), and IAS connectivity (0.81-0.97 m2 m-2) across all bromeliad leaves. The revised gIAS model predicted significantly lower gIAS in CAM (0.01-0.19 mol m-2 s-1 bar-1) than in C3 (0.41-2.38 mol m-2 s-1 bar-1) plants due to a coordinated decline in these IAS traits. Our reevaluated equation also generally predicted lower gIAS values than the former one. Moreover, we observed high spatial heterogeneity in these IAS geometric traits throughout the mesophyll, especially within CAM leaves. Our data show that IAS traits that better capture the 3D complexity of leaves strongly influence gIAS and that the impact of the IAS on mesophyll conductance should be carefully considered with respect to leaf anatomy. We provide a simple function to estimate tortuosity and lateral path lengthening in the absence of access to imaging tools such as x-ray microcomputed tomography or other novel 3D image-processing techniques.


Asunto(s)
Bromeliaceae/metabolismo , Dióxido de Carbono/metabolismo , Células del Mesófilo/metabolismo , Hojas de la Planta/metabolismo , Algoritmos , Bromeliaceae/clasificación , Bromeliaceae/genética , Difusión , Fotosíntesis , Filogenia , Hojas de la Planta/anatomía & histología , Hojas de la Planta/citología , Porosidad , Especificidad de la Especie , Microtomografía por Rayos X
5.
Mol Phylogenet Evol ; 107: 152-165, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27989631

RESUMEN

Cryptanthus comprises 72 species endemic to eastern Brazil with a center of diversity in the Atlantic Forest. The majority of the species are threatened due to habitat loss. We reconstructed phylogenetic relationships in Cryptanthus based on amplified fragment length polymorphisms (AFLP) including 48 species and 109 accessions. The Bayesian phylogenetic analysis revealed four major lineages in Cryptanthus and provided further evidence for the paraphyly of subgen. Hoplocryptanthus, while subgenus Cryptanthus was resolved as monophyletic. Monophyly of previously recognized morphological species groups at sectional level could not be confirmed. Based on the phylogenetic reconstruction we inferred the evolution of the sex system in Cryptanthus via maximum likelihood (ML) ancestral character reconstruction. Homoecy, the possession of hermaphrodite flowers only, was reconstructed as the ancestral state in the genus and characterizes three of the four main lineages within Cryptanthus. Andromonoecy, the possession of male and hermaphrodite flowers on the same plant, evolved only once and represents a synapomorphy of the fourth main lineage, C. subgen. Cryptanthus. The ancestral biome analysis reconstructed Cerrado (semiarid scrublands and forests) and campos rupestres (rock fields) as the most likely ancestral biomes for the genus. A shift to the Atlantic Forest biome was reconstructed to have occurred twice, in the ancestor of the first diverging lineage within the genus and in the ancestor of the C. subgen. Cryptanthus clade. A shift to the Caatinga (tropical dryland savanna) and one reversal to Cerrado (campos rupestres - rock fields) was reconstructed to have occurred once, in C. bahianus and C. arelii, respectively. The ancestral biome reconstruction indicates a high degree of niche conservatism within Cryptanthus with rare biome shifts throughout the evolution of the genus. Further, our results imply that the current infrageneric taxonomy of Cryptanthus is problematic and requires revision.


Asunto(s)
Bromeliaceae/clasificación , Filogenia , Filogeografía , Análisis del Polimorfismo de Longitud de Fragmentos Amplificados , Teorema de Bayes , Bromeliaceae/genética , Ecosistema , Geografía , Funciones de Verosimilitud
6.
Ann Bot ; 120(2): 233-243, 2017 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-28052858

RESUMEN

Background and Aims: The distribution of polyploidy along a relatively steep Andean elevation and climatic gradient is studied using the genus Fosterella L.B. Sm. (Bromeliaceae) as a model system. Ecological differentiation of cytotypes and the link of polyploidy with historical biogeographic processes such as dispersal events and range shift are assessed. Methods: 4',6-Diamidino-2-phenylindole (DAPI) staining of nuclei and flow cytometry were used to estimate the ploidy levels of 159 plants from 22 species sampled throughout the distribution range of the genus. Ecological differentiation among ploidy levels was tested by comparing the sets of climatic variables. Ancestral chromosome number reconstruction was carried out on the basis of a previously generated phylogeographic framework. Key Results: This study represents the first assessment of intrageneric, intraspecific and partially intrapopulational cytotype diversity in a genus of the Bromeliaceae family. In Fosterella , the occurrence of polyploidy was limited to the phylogenetically isolated penduliflora and rusbyi groups. Cytotypes were found to be ecologically differentiated, showing that polyploids preferentially occupy colder habitats with high annual temperature variability (seasonality). The combined effects of biogeographic history and adaptive processes are presumed to have shaped the current cytotype distribution in the genus. Conclusions: The results provide indirect evidence for both adaptive ecological and non-adaptive historical processes that jointly influenced the cytotype distribution in the predominantly Andean genus Fosterella (Bromeliaceae). The results also exemplify the role of polyploidy as an important driver of speciation in a topographically highly structured and thus climatically diverse landscape.


Asunto(s)
Bromeliaceae/clasificación , Poliploidía , Adaptación Biológica , Altitud , Evolución Biológica , Bromeliaceae/genética , Clima , Filogeografía , América del Sur
7.
Am J Bot ; 104(7): 1073-1087, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28710126

RESUMEN

PREMISE OF THE STUDY: The yellow-flowered Aechmea subgenus Ortgiesia (yfAsO) (Bromeliaceae) is a group of seven morphologically similar bromeliads found mostly in the southern Brazilian Atlantic rainforest. The recent origin of this group probably contributes to its taxonomic complexity. The aims of this study were to investigate the levels of genetic diversity and structure at the population and species levels, to gain insight into the processes behind the diversification of the group, and to contribute to the establishment of species boundaries. METHODS: We sequenced two noncoding regions of the chloroplast genome (rpl32-trnL and rps16-trnK) and the nuclear phyC gene in 204 and 153 individuals, respectively, representing the seven species of the group. Phylogeographical and population genetics approaches were used. KEY RESULTS: Three of the seven yfAsO showed some degree of genetic differentiation among species. Divergence time for the group was dated to around 4 million years ago. Areas of conservation value were identified, and a scenario of multiple refugia in the southern Brazilian Atlantic rainforest during the Pleistocene climatic oscillations is suggested. CONCLUSIONS: We hypothesized that incomplete lineage sorting and localized hybridization events are responsible for the low levels of genetic differentiation and the taxonomic complexity observed among and within the seven yfAsO species. Further studies on Aechmea comata and Aechmea kertesziae will be necessary to clarify the boundary between these two species. Most of the populations sampled showed high genetic diversity and/or unique haplotypes; they should be prioritized for conservation purposes.


Asunto(s)
Bromeliaceae/clasificación , Variación Genética , Hibridación Genética , Filogenia , Evolución Biológica , Brasil , Bromeliaceae/genética , Genética de Población , Haplotipos , Filogeografía , Análisis de Secuencia de ADN
8.
An Acad Bras Cienc ; 89(2): 1085-1093, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28489202

RESUMEN

It is not unusual to find epiphytic bromeliads in mangroves, but most studies on mangrove vegetation do not record their presence. This study aimed to evaluate the diversity and distribution of epiphytic bromeliads in a subtropical mangrove. The richness, abundance and life form (atmospheric and tank) of bromeliads were recorded and compared among host tree species and waterline proximity. The effects of diameter and height of host trees on the abundance of bromeliads were also assessed. The mangrove was composed of Avicennia schaueriana, Laguncularia racemosa and Rhizophora mangle. We recorded seven bromeliad species of the genera Tillandsia and Vriesea. The waterline proximity did not affect the abundance or diversity of bromeliads, but atmospheric forms were predominant near the waterline, whereas tank bromeliads were more frequent in the interior of the mangrove. The three mangrove species hosted bromeliads, but L. racemosa was the preferred host. The species composition showed that the distribution of bromeliads is more related to the host species than to the distance from the waterline. Bromeliad abundance increased with tree size. Bromeliads can be biological indicators of ecosystem health; therefore, inventories and host tree preferences are necessary knowledge for an adequate management of sensitive ecosystems as mangroves.


Asunto(s)
Bromeliaceae , Humedales , Análisis de Varianza , Avicennia , Biodiversidad , Brasil , Bromeliaceae/clasificación , Clima , Análisis de Regresión
9.
An Acad Bras Cienc ; 89(4): 3067-3082, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29236853

RESUMEN

Pollen morphology characterization is important in taxonomy, conservation and plant breeding, and pollen viability studies can support breeding programs. This study investigated pollen morphology and male fertility in 18 species of Bromeliaceae with ornamental potential. For morphological characterization, pollen grains were acetolyzed and characterization of exine was done using scanning and transmission electron microscopy. Pollen viability was investigated by in vitro germination and histochemical tests. Species belonging to Aechmea and Ananas genera presented medium size pollen, except for Ae. fasciata, with large pollen. Al. nahoumii, P. sagenarius and the Vriesea species analyzed showed large pollen, except for V. carinata, with very large pollen. Pollen of Aechmea, Ananas and P. sagenarius presented bilateral symmetry, diporate, exine varying from tectate to semitectate. Al. nahoumii and Vriesea species presented pollen with bilateral symmetry, monocolpate; exine was semitectate, reticulate and heterobrochate. Germination percentage and tube growth were greater in SM and BKM media. Histochemical tests showed pollen viability above 70% for all species, except for Ananas sp. (40%). Pollen morphology is important for the identification of species, especially in this family, which contains a large number of species. High rates of viability favor fertilization and seed production, essential for efficient hybrid production and conservation.


Asunto(s)
Bromeliaceae/fisiología , Polen/fisiología , Bromeliaceae/clasificación , Bromeliaceae/ultraestructura , Inmunohistoquímica , Microscopía Electrónica , Polen/crecimiento & desarrollo , Polen/ultraestructura
10.
Genet Mol Res ; 16(2)2017 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-28437558

RESUMEN

The Bromeliaceae family includes a range of species used for many purposes, including ornamental use and use as food, medicine, feed, and fiber. The state of Espírito Santo, Brazil is a center of diversity for this family in the Atlantic Forest. We evaluated the genetic diversity of five populations of the Bromeliaceae family, including specimens of the genera Aechmea, Billbergia (subfamily Bromelioideae), and Pitcairnia (subfamily Pitcairnioidea), all found in the Atlantic Forest and distributed in the state of Espírito Santo. The number of alleles per locus in populations ranged from two to six and the fixation index (F), estimated for some simple sequence repeats in bromeliad populations, was less than zero in all populations. All markers in the Pitcairnia flammea population were in Hardy-Weinberg equilibrium (P < 0.05). Moreover, significant deviations from Hardy-Weinberg equilibrium were observed at some loci in populations of the five bromeliad species. In most cases, this can be attributed to the presence of inbreeding or the Wahlund effect. The genetic diversity indices of five species showed greater allelic richness in P. flammea (3.55). Therefore, we provide useful information for the characterization of genetic diversity in natural populations of Aechmea ramosa, Aechmea nudicaulis, Billbergia horrid, Billbergia euphemia, and P. flammea in Atlantic Forest remnants in the south of Espírito Santo state.


Asunto(s)
Biodiversidad , Bromeliaceae/genética , Bosques , Polimorfismo Genético , Alelos , Brasil , Bromeliaceae/clasificación , Sitios Genéticos , Endogamia
11.
Mol Phylogenet Evol ; 98: 346-57, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26957015

RESUMEN

Aechmea subgenus Ortgiesia comprises ca. 20 species distributed in Brazil, Argentina, Paraguay, and Uruguay, with a center of diversity in the Brazilian Atlantic rainforest. We examined interspecific relationships of Ortgiesia based on Amplified Fragment Length Polymorphisms (AFLP). Ninety-six accessions belonging to 14 species of Ortgiesia were sampled, and genotyped with 11 AFLP primer combinations. The neighbor joining (NJ) tree depicted two main genetic groups within Aechmea subgenus Ortgiesia, and four subgroups. The NJ tree showed short internal branches, indicating an overall shallow genetic divergence among Ortgiesia species as expected for the recently radiated subfamily Bromelioideae. Our results suggest that hybridization and/or incomplete lineage sorting may have hampered the reconstruction of interspecific relationships in Aechmea subgenus Ortgiesia. The mapping of petal color (yellow, blue, pink, or white), inflorescence type (simple or compound), and inflorescence shape (ellipsoid, subcylindric, cylindric, or pyramidal) against the NJ tree indicated that these characters are of limited taxonomic use in Aechmea subgenus Ortgiesia due to homoplasy. An analysis of the current distribution of Ortgiesia identified the southern region of the Brazilian Atlantic rainforest, between latitudes of 26° and 27°S, as the center of diversity for the subgenus.


Asunto(s)
Análisis del Polimorfismo de Longitud de Fragmentos Amplificados , Bromeliaceae/clasificación , Bromeliaceae/genética , Filogenia , Polimorfismo Genético/genética , Bosque Lluvioso , Argentina , Océano Atlántico , Brasil , Bromeliaceae/anatomía & histología , Bromeliaceae/fisiología , Hibridación Genética , Inflorescencia/clasificación , Inflorescencia/genética , Inflorescencia/fisiología , Paraguay , Uruguay
12.
Mol Phylogenet Evol ; 100: 1-20, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27060423

RESUMEN

The tank-epiphytic clade of berry-fruited bromeliads, also known as the Core Bromelioideae, represents a remarkable event of adaptive radiation within the Bromeliaceae; however, the details of this radiation have been difficult to study because this lineage is plagued with generic delimitation problems. In this study, we used a phylogenetic approach to investigate a well supported, albeit poorly understood, lineage nested within the Core Bromelioideae, here called the "Ronnbergia Alliance". In order to assess the monophyly and phylogenetic relationships of this group, we used three plastid and three nuclear DNA sequence markers combined with a broad sampling across three taxonomic groups and allied species of Aechmea expected to comprise the Ronnbergia Alliance. We combined the datasets to produce a well-supported and resolved phylogenetic hypothesis. Our main results indicated that the Ronnbergia Alliance was a well-supported monophyletic group, sister to the remaining Core Bromelioideae, and it was composed by species of the polyphyletic genera Aechmea, Hohenbergia and Ronnbergia. We identified two major internal lineages with high geographic structure within the Ronnbergia Alliance. The first of these lineages, called the Pacific Clade, contained species of Aechmea and Ronnbergia that occur exclusively from southern Central America to northwestern South America. The second clade, called the Atlantic Clade, contained species of Aechmea, Hohenbergia and Ronnbergia mostly limited to the Atlantic Forest and the Caribbean. We also explored the diagnostic and evolutionary importance of 13 selected characters using ancestral character reconstructions on the phylogenetic hypothesis. We found that the combination of tubular corollas apically spreading and unappendaged ovules had diagnostic value for the Ronnbergia Alliance, whereas flower size, length of the corolla tube, and petal pigmentation and apex were important characters to differentiate the Pacific and Atlantic clades. This study opens new perspectives for future taxonomic reorganizations and provides a framework for evolutionary and biogeographic studies.


Asunto(s)
Bromeliaceae/anatomía & histología , Bromeliaceae/clasificación , Filogenia , Océano Atlántico , Teorema de Bayes , Bromeliaceae/genética , Núcleo Celular/genética , ADN de Cloroplastos/genética , ADN de Plantas/genética , Bases de Datos de Ácidos Nucleicos , Geografía , Funciones de Verosimilitud , Océano Pacífico , Análisis de Secuencia de ADN , Especificidad de la Especie
13.
An Acad Bras Cienc ; 88 Suppl 1: 439-49, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27168370

RESUMEN

Pollen grain morphology of Bromeliaceae species collected in areas of the Atlantic Rainforest of southeastern Brazil was studied. The following species were analyzed: Aechmea bambusoides L.B.Sm. & Reitz, A. nudicaulis (L.) Griseb., A. ramosa Mart. ex Schult.f., Ananas bracteatus (Lindl.) Schult.f., Billbergia distachia (Vell.) Mez, B. euphemiae E. Morren, B. horrida Regel, B. zebrina (Herb.) Lindl., Portea petropolitana (Wawra) Mez, Pitcairnia flammea Lindl., Quesnelia indecora Mez, Tillandsia polystachia (L.) L., T. stricta Sol., T. gardneri Lindl., T. geminiflora Brongn. and Vriesea grandiflora Leme. Light and scanning electron microscopy were used and the species were grouped into three pollen types, organized according to aperture characteristics: Type I - pantoporate pollen grains observed in P. petropolitana, Type II - 2-porate pollen grains, observed in the genera Ananas, Aechmea and Quesnelia, and Type III - 1-colpate pollen grains, observed in the genera Billbergia, Pitcairnia, Tillandsia and Vriesea. Pollen data led to the construction of an identification key. The results showed that the species analyzed can be distinguished using mainly aperture features and exine ornamentation, and that these characteristics may assist in taxonomic studies of the family.


Asunto(s)
Bromeliaceae/anatomía & histología , Polen/anatomía & histología , Bosque Lluvioso , Brasil , Bromeliaceae/clasificación , Microscopía Electrónica de Rastreo , Polen/ultraestructura , Especificidad de la Especie
14.
J Eukaryot Microbiol ; 62(6): 737-49, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25963550

RESUMEN

This study evaluated the influence of rainfall amount on the abundance, species richness, and species occurrence and abundance distribution of the ciliate community associated with the bromeliad Aechmea distichantha. The plants were collected from a rock wall of about 10-km long at the left bank of Paraná River. We assessed the effects of both spatial and temporal variables on the community attributes, as well as whether plants geographically closer have a similar abundance distribution and species composition. The ciliate community was substantially distinct between both hydrological periods, with greater values of species richness and abundance in the rainy period. No spatial structuring (differences in the species occurrence and abundance distribution among strata) or geographical similarity (similarity in ciliate species composition among the plants) was found. Multiple regression analysis showed a positive relationship only between the ciliate abundances and water volumes for both periods. Although few of the formulated predictions were confirmed, our study provides valuable information on the ecological aspects of the ciliate community inhabiting bromeliad phytotelmata.


Asunto(s)
Bromeliaceae/crecimiento & desarrollo , Cilióforos/crecimiento & desarrollo , Agua Dulce/parasitología , Ríos/parasitología , Análisis de Varianza , Biodiversidad , Biota , Brasil , Bromeliaceae/clasificación , Cilióforos/aislamiento & purificación , Ecosistema , Genotipo , Plancton/crecimiento & desarrollo , Lluvia , Estaciones del Año , Clima Tropical
15.
An Acad Bras Cienc ; 87(2): 835-42, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25910174

RESUMEN

Billbergia horrida is endemic of the Atlantic Forest fragments in southeastern Brazil and characterized by flowers with typical traits for pollination by nocturnal animals. Although the majority of Billbergia species rely on diurnal pollination by hummingbirds, B. horrida is also visited by bats and this study evidences for the first time the occurrence of chiropterophily within the genus. The role of different groups of pollinators on the reproductive success of B. horrida was evaluated, as well as the correlation of nectar features in sustaining these animals during different periods of the day. Bats contributed to 82.1% of fruit set of B. horrida. Hummingbirds, in turn, contributed to only 10% of fruit set, and were poorly related to the reproductive success of this species. Amounts of nectar production and sugar concentration were similar to those of other chiropterophilous bromeliads and only the nectar volume changed significantly throughout the period of flower availability. Recurring visits by hummingbirds were probably because the flowers of B. horrida were open for 24h, offering energetic rewards for daytime visitors and due to the presence of other attractive bromeliad species growing at the same phorophyte and flowering at the same time.


Asunto(s)
Aves/fisiología , Bromeliaceae/crecimiento & desarrollo , Quirópteros/fisiología , Ritmo Circadiano/fisiología , Polinización/fisiología , Animales , Aves/clasificación , Bromeliaceae/clasificación , Quirópteros/clasificación
16.
Genet Mol Res ; 14(4): 15892-901, 2015 Dec 03.
Artículo en Inglés | MEDLINE | ID: mdl-26634557

RESUMEN

Bromeliads are greatly represented in the Atlantic Forest, although many species are threatened with extinction owing to habitat fragmentation and intense extraction for ornamental purposes. Therefore, it is necessary to conduct studies generating knowledge about genetic diversity and the distribution of this diversity among and within natural populations to establish conservation strategies. These studies can be performed with the use of molecular markers. Molecular markers are advantageous for studies of natural populations, for conservation programs, and to aid in properly classifying plant species. This study aimed to evaluate the genetic diversity among and within natural populations of Pitcairnia flammea, occurring in three fragments of the Atlantic Forest in the southern State of Espírito Santo through the use of inter-simple sequence repeat (ISSR) markers. DNA samples from 55 individuals were amplified with 18 ISSR primers, generating 180 bands, 159 of which were polymorphic. The Shannon genetic diversity index ranged from 0.348 to 0.465, with an average of 0.412. The Bayesian approach for the molecular data indicated the existence of two genetic groups. Analysis of molecular variance indicated the existence of 90.3% diversity within the population and 9.74% among populations. The amount of genetic differentiation of populations was moderate (0.0974), indicating that gene flow rates may be enough to counteract the effects of genetic drift. Greater genetic variability found in population B indicates that this area is an important source of genetic variability.


Asunto(s)
Bromeliaceae/genética , Variación Genética , Genética de Población , Repeticiones de Microsatélite , Bromeliaceae/clasificación , ADN de Plantas , Marcadores Genéticos , Genotipo , Filogenia
17.
Mol Phylogenet Evol ; 77: 54-64, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24657431

RESUMEN

The saxicolous genus Orthophytum (∼60 species, Bromeliaceae) is endemic to eastern Brazil and diversified in xeric habitats of the Atlantic Rainforest, Caatinga and campos rupestres. Within the genus, two main groups are discerned based on the presence or absence of a pedunculate inflorescence, which are further subdivided into several morphological subgroups. However, these systematic hypotheses have not yet been tested in a molecular phylogenetic framework. Here we present the first phylogenetic analysis of Orthophytum using nuclear and plastid markers (phytochrome C, and trnH-psbA and trnL-trnF spacers). Forty species representing the two main groups and all subgroups of Orthophytum, and the related genera Cryptanthus (8 spp.) and Lapanthus (2 spp.) were analyzed. The phylogenetic reconstruction revealed a well-supported clade termed Eu-Orthophytum, containing species with pedunculate inflorescences only. The Orthophytum species with sessile inflorescence formed two clades: (1) the amoenum group and (2) the vagans group plus O. foliosum, the only pedunculate Orthophytum species found outside Eu-Orthophytum. The vagans clade is in sister group position to Eu-Orthophytum. Within the latter, the subgroup mello-barretoi was sister to the most diversified clade, termed Core Orthophytum. Morphological character state reconstructions of floral characters used in previous taxonomic treatments as key diagnostic characters (penduncle presence, corolla form, and petal appendage form) showed different levels of homoplasy.


Asunto(s)
Bromeliaceae/genética , Evolución Molecular , Filogenia , Proteínas de Plantas/genética , Teorema de Bayes , Bromeliaceae/anatomía & histología , Bromeliaceae/clasificación , Plastidios/genética
18.
An Acad Bras Cienc ; 86(4): 1849-62, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25590721

RESUMEN

In Bromeliaceae, cytogenetic and flow cytometry analyses have been performed to clarify systematic and evolutionary aspects. Karyotyping approaches have shown the relatively high chromosome number, similar morphology and small size of the chromosomes. These facts have prevented a correct chromosome counting and characterization. Authors have established a basic chromosome number of x = 25 for Bromeliaceae. Recently, one karyomorphological analysis revealed that x = 25 is no longer the basic chromosome number, whose genome may have a polyploid origin. Besides cytogenetic characterization, the 2C DNA content of bromeliads has been measured. Nuclear DNA content has varied from 2C = 0.60 to 2C = 3.34 picograms. Thus, in relation to most angiosperms, the 2C DNA content of Bromeliaceae species as well as their chromosome size can be considered relatively small. In spite of some advances, cytogenetic and flow cytometry data are extremely scarce in this group. In this context, this review reports the state of the art in karyotype characterization and nuclear DNA content measurement in Bromeliaceae, emphasizing the main problems and suggesting prospective solutions and ideas for future research.


Asunto(s)
Bromeliaceae/genética , Cariotipificación , Bromeliaceae/clasificación , Cromosomas de las Plantas , ADN de Plantas/genética , Citometría de Flujo
19.
J Eukaryot Microbiol ; 60(3): 223-34, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23346872

RESUMEN

Using morphological, morphometric, and molecular methods, we describe Bromeliophrya quadristicha n. spec. from tank bromeliads of Jamaica and the Dominican Republic. The new species differs from the single congener, B. brasiliensis, mainly in having four (vs. 2) left lateral kinetofragments, 23 (vs. 32) ciliary rows, and a short (vs. long and C-shaped) adoral membranelle 3. Both the morphological and molecular phylogenies show Bromeliophrya and Glaucomides as sister group of the Glaucomidae. Thus, they should have the same (family) rank.


Asunto(s)
Bromeliaceae/clasificación , Cilióforos/clasificación , Bromeliaceae/anatomía & histología , Bromeliaceae/genética , Cilióforos/genética , República Dominicana , Jamaica , Filogenia
20.
ScientificWorldJournal ; 2013: 307593, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23864825

RESUMEN

Some species of Dyckia Schult. f., including Dyckia brevifolia Baker, are rheophytes that live in the fast-moving water currents of streams and rivers which are subject to frequent flooding, but also period of low water. This study aimed to analyze the leaf epidermis of D. brevifolia in the context of epidermal adaptation to this aquatic plant's rheophytic habitat. The epidermis is uniseriate, and the cuticle is thickened. The inner periclinal and anticlinal walls of the epidermal cells are thickened and lignified. Stomata are tetracytic, located in the depressions in relation to the surrounding epidermal cells, and covered by peltate trichomes. While the epidermal characteristics of D. brevifolia are similar to those of Bromeliaceae species, this species has made particular adaptations of leaf epidermis in response to its rheophytic environment.


Asunto(s)
Bromeliaceae/clasificación , Bromeliaceae/ultraestructura , Epidermis de la Planta/ultraestructura , Hojas de la Planta/ultraestructura , Epidermis de la Planta/clasificación , Hojas de la Planta/clasificación
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