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1.
Microsc Res Tech ; 85(1): 253-269, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34369639

RESUMO

Tillandsia L. is the largest genus of the family Bromeliaceae, containing 755 species and seven subgenera. Morphoanatomical studies of leaves provide useful characteristics to phylogenetic, taxonomic, and ecological analyses. This study aims to characterize and compare the leaves of 24 species of the four subgenera of Tillandsia that occur in Bahia and also perform adaptative inferences to environmental responses. The results of the species' morphoanatomical studies were compared through dissimilarity analysis. The species have rosulate leaves with varying lengths and widths. The peltate trichomes present variation in the indument density and the length of their wing and central disk. The stomata are longitudinally distributed in one or both sides of the limb. The mesophyll is dorsiventral and presents aquiferous and chlorophyllic parenchymas. The vascular bundles are collateral and partially covered by fibers, except for Tillandsia linearis. Based on the dissimilarity analysis, it was possible to identify the formation of five groups. Group G1 was composed of T. linearis, which diverged from the other species of the subgenus. Group G2 was formed by the remaining species of the subgenus Phytarrhiza. G3 and G4 presented the species of the subgenus Diaphoranthema and Tillandsia, respectively. Group G5 gathered 11 species of the subgenus Anoplophytum and presented higher variability than the other subgenera. Based on the results, the morphoanatomical characteristics can be used to characterize and group Tillandsia species, besides confirming the morphological variability of these species to the epiphyte habit in different environments, especially xeric ones.


Assuntos
Bromeliaceae , Tillandsia , Animais , Microscopia Eletrônica de Varredura , Filogenia , Folhas de Planta
2.
Sci Total Environ ; 811: 152384, 2022 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-34923012

RESUMO

While numerous studies reported hormesis in plants exposed to heavy metals, metals were commonly added in the growth substrate (e.g. soil or solution). The potential of heavy metals in the atmosphere to induce hormesis in plants, however, remains unknown. In this study, we exposed the widely-used accumulator plant Tillandsia usneoides to 10 atmospheric Pb concentrations (0-25.6 µg·m-3) for 6 or 12 h. Three types of dose-response relationships between different response endpoints (biomarkers) and Pb concentrations were found for T. usneoides. The first was a monophasic dose response, in which the response increased linearly with increasing Pb concentrations, as seen for metallothionein (MT) content after a 6-h exposure. The second and dominating type was a biphasic-hormetic dose response, exhibited by malondialdehyde (MDA), superoxide anion radical (O2-), and superoxide dismutase (SOD) after 6 or 12 h of exposure and by glutathione (GSH) and MT content after 12 h of treatment. The third type was a triphasic dose response, as seen for leaf electric conductivity after 6 or 12 h of exposure and GSH after 6 h of exposure. This finding suggests that Pb inhibited the response of T. usneoides at very low concentrations, stimulated it at low-to-moderate concentrations, and inhibited it at higher concentrations. Our results demonstrate diverse adaptation mechanisms of plants to stress, in the framework of which alternating between up- and down-regulation of biomarkers is at play when responding to different levels of toxicants. The emergence of the triphasic dose response will further enhance the understanding of time-dependent hormesis.


Assuntos
Metais Pesados , Tillandsia , Atmosfera , Hormese , Chumbo/toxicidade
3.
Sci Rep ; 11(1): 20397, 2021 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-34650134

RESUMO

The rapid spread of many weeds into intensely disturbed landscapes is boosted by clonal growth and self-fertilization strategies, which conversely increases the genetic structure of populations. Here, we use empirical and modeling approaches to evaluate the spreading dynamics of Tillandsia recurvata (L.) L. populations, a common epiphytic weed with self-reproduction and clonal growth widespread in dry forests and deforested landscapes in the American continent. We introduce the TRec model, an individual-based approach to simulate the spreading of T. recurvata over time and across landscapes subjected to abrupt changes in tree density with the parameters adjusted according to the empirical genetic data based on microsatellites genotypes. Simulations with this model showed that the strong spatial genetic structure observed from empirical data in T. recurvata can be explained by a rapid increase in abundance and gene flow followed by stabilization after ca. 25 years. TRec model's results also indicate that deforestation is a turning point for the rapid increase in both individual abundance and gene flow among T. recurvata subpopulations occurring in formerly dense forests. Active reforestation can, in turn, reverse such a scenario, although with a milder intensity. The genetic-based study suggests that anthropogenic changes in landscapes may strongly affect the population dynamics of species with 'weedy' traits.


Assuntos
Conservação dos Recursos Naturais , Espécies Introduzidas , Tillandsia , Brasil , Fluxo Gênico/genética , Repetições de Microssatélites/genética , Dinâmica Populacional , Tillandsia/genética , Tillandsia/fisiologia
4.
Phytomedicine ; 89: 153622, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34161895

RESUMO

BACKGROUND: Type 2 Diabetes (T2D) is characterized by deregulation in carbohydrate and lipid metabolism, with a very high mortality rate. Glucose Transporter type 4 (GLUT4) plays a crucial role in T2D and represents a therapeutic target of interest. Tillandsia usneoides (T. usneoides) is a plant used as a remedy for diabetes. T. usneoides decreased blood glucose in different experimental models. However, the involvement of GLUT4 in this effect has not yet been explored. PURPOSE: This study aimed to investigate whether any component in T. usneoides might participate in the effect on blood glucose through a bioassay-guided fractionation, testing its potential antihyperglycemic effect in mice, as well as its influence on GLUT4 translocation in C2C12 myoblasts and primary hepatocytes. METHODS: The aqueous extract and the Ethyl Acetate fraction (TU-AcOEt) of T. usneoides were evaluated in a hypoglycemic activity bioassay and in the glucose tolerance test in CD-1 mice. TU-AcOEt was fractionated, obtaining five fractions that were studied in an additional glucose tolerance test. C1F3 was fractioned again, and its fractions (C2F9-12, C2F22-25, and C2F38-44) were examined by HPLC. The C2F38-44 fraction was analyzed by Mass Spectrometry (MS) and subjected to additional fractionation. The fraction C3F6-9 was explored by Nuclear Magnetic Resonance (NMR), resulting in 5,7,4´-trihydroxy-3,6,3´,5´-tetramethoxyflavone (Flav1). Subsequently, a viability test was performed to evaluate the cytotoxic effect of Flav1 and fractions C2F9-12, C2F22-25. C2F38-44, and C3F30-41 in C2C12 myoblasts and primary mouse hepatocytes. Confocal microscopy was also performed to assess the effect of Flav1 and fractions on GLUT4 translocation. RESULTS: The TU-AcOEt fraction exhibited a hypoglycemic and antihyperglycemic effect in mice, and its fractionation resulted in five fractions, among which fraction C1F3 decreased blood glucose. MS and NMR analysis revealed the presence of Flav1. Finally, Flav1 significantly promoted the translocation of GLUT4 in C2C12 myoblasts and primary hepatocytes. CONCLUSION: To date, Flav1 has not been reported to have activity in GLUT4; this study provides evidence that T. usneoides is a plant with the potential to develop novel therapeutic agents for the control of T2D.


Assuntos
Diabetes Mellitus Tipo 2 , Flavonas , Transportador de Glucose Tipo 4/metabolismo , Hepatócitos/efeitos dos fármacos , Hipoglicemiantes , Mioblastos/efeitos dos fármacos , Animais , Linhagem Celular , Diabetes Mellitus Tipo 2/tratamento farmacológico , Flavonas/farmacologia , Hipoglicemiantes/farmacologia , Camundongos , Compostos Fitoquímicos/farmacologia , Tillandsia/química
5.
J Hazard Mater ; 414: 125529, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-34030407

RESUMO

Atmospheric Hg is a highly toxic heavy metal with bioaccumulative properties. However, relatively few studies have focused on the distribution of Hg in cellular and subcellular structures of plants and factors influencing its accumulation. In this study, we selected Tillandsia usneoides, which is a widely used bioindicator for Hg, to analyze the concentration of Hg in different cells (foliar trichomes, epidermal cells, mesophyll cells, and vascular bundle cells), different subcellular structures (cell wall, cell membrane, vacuoles, and organelles) and different cell wall components (pectin, hemicellulose 1, and hemicellulose 2). It was determined that Hg was present in different types of cells, but there was no significant difference, suggesting that atmospheric Hg circulates dynamically in the surface and internal structural cells of T. usneoides leaves. Subcellular analysis showed that as Hg concentration increased, more Hg accumulated in the vacuoles and cell wall through the compartmentalization mechanism. Hemicellulose had the highest content of Hg, indicating that it is the primary Hg-binding component of the cell wall. The FTIR analysis results showed that after the Hg treatment, the cell wall -OH and COO- absorption peaks changed most significantly, indicating that these functional groups play a vital role in the Hg accumulation process.


Assuntos
Mercúrio , Tillandsia , Folhas de Planta
6.
New Phytol ; 231(5): 1906-1922, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33690891

RESUMO

Tillandsia usneoides in epiphytic bromeliads takes up water through absorptive trichomes on the shoot surface under extreme environmental conditions. Although previous studies revealed the way by which T. usneoides absorbs water and prevents water loss, its water transport remains unclear. We characterized structures of trichome wings of T. usneoides. Wing length-to-thickness ratio of 136 and trichome interval (d)-to-wing length (l) ratio (d/l) smaller than 1 caused the water film to flatten the wings sequentially, resulting in domino-like water transport. A hinge-like linkage between wing and outer ring cells and the wing size longer than the elastocapillary length (LEC ) brought about this unique reconfiguration, which is the flattening and recovery of wings. Tillandsia usneoides transported water rapidly on the surface as the water film propagated on the exterior trichomes with flexible wings and the transport distance at the macroscopic scale grew as tx with x = 0.68 ± 0.04, unlike the conventional scaling of t0.5 . Empirical and theoretical investigations proved our assumption that external water transport with the domino-like effect predominated over internal vascular transport. Biomimetic trichome wings simulated the domino-like water transport, highlighting the important role of flexible wing arrays.


Assuntos
Tillandsia , Transporte Biológico , Folhas de Planta , Tricomas , Água
7.
Bull Environ Contam Toxicol ; 107(1): 69-76, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33666681

RESUMO

In the present study, an urban and industrial area were evaluated through a biomonitoring study employing the Tillandsia purpurea and T. latifolia species as a biomonitor. Plants were collected from a non-contaminated area and transplanted and exposed for three months into study areas to determine metal accumulation. Sixteen elements (Al, As, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Ni, Pb, Rb, Sb, V, and Zn) were measured using ICP-MS analysis. Datasets were assessed by one-way ANOVA, exposed-to-baseline (EB) ratio, and principal component analysis. Results showed significant differences among study areas for most elements, but no differences were found between species. According to EB ratios, As, Cd, Cr, Cu, Fe, Ni, Pb, Sb, V, and Zn showed EB ratios > 1.75 for both Tillandsia species around the industrial area, indicating influence from the Smelter plant. Ba, Sb, and Zn showed EB ratios > .1.75 in the urban area for both plants, indicating the releasing of pollutants from vehicular sources. PCA showed that most elements are derived from vehicular sources, industrial activities, and dust resuspension.


Assuntos
Poluentes Atmosféricos , Metais Pesados , Tillandsia , Poluentes Atmosféricos/análise , Monitoramento Biológico , Poeira/análise , Monitoramento Ambiental , Metais Pesados/análise
8.
Microsc Res Tech ; 84(3): 441-459, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32959456

RESUMO

Tillandsia is the bromeliad genus containing the largest number of species, with wide geographic dispersion and an important ecological role in the ecosystems. Investigations of pollen morphology are important to support taxonomic and conservation studies as well as to choose promising species for cross-pollination to obtain hybrids. The objective of this study was to evaluate the morphology, production, and viability of pollen grains of 24 Tillandsia species that naturally occur in the state of Bahia, Brazil. Pollen grains were acetolized and analyzed by scanning electron microscopy. The pollen were germinated in vitro in two culture media (BM and BKM) and collected at three floral development stages (pre-anthesis, anthesis and post-anthesis). Pollen viability also was analyzed by staining with Alexander's solution and acetocarmine in three floral development stages. Variations in the ornamentation and size of the pollen were observed among the species studied, with the majority having medium size, while T. polystachia and T. juncea had large grains and the subgenera Diaphoranthema and Phytarrhiza had small grains. The pollen of the majority of species had bilateral symmetry, with a single irregularly shaped colpus, semitectate exine and reticulated-heterobrochate surface. The pollen presented high germination percentage, tube length and viability according to the histochemistry, except for T. recurvata, T. usneoides and T. loliacea. The BKM medium and collection of pollen during anthesis produced the best results for the Tillandsia species. The results can support studies of the taxonomy and conservation of these species, which have great environmental importance and high value for ornamental purposes.


Assuntos
Bromeliaceae , Tillandsia , Ecossistema , Microscopia Eletrônica de Varredura , Pólen
9.
Int J Phytoremediation ; 23(4): 400-406, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32930602

RESUMO

Epiphytic Tillandsia species are uniquely suitable for the study of foliar uptake of atmospheric trace metals (ATM) because these plants can only rely on their leaves for this purpose. Therefore, we analyzed the uptake and transport of different metals (Fe, Al, Zn, Mn, Ba, Ti, Cu, Ni, Cr, Sn, Pb, Co, As, and Se) bounded on atmospheric particulate matters (APM) in Tillandsia brachycaulos Schltdl. The results showed that the metal contents inside leaves significantly (p < .05) increased after APM exposure. There was a significant (p < .05) positive correlation between the content of 14 trace metals accumulated on the leaf surface and inside the leaf, which indicated that APM is the main source of ATM uptake. The subcellular analysis showed that the Pb, Cu, Ni, Zn, and Cr absorbed by T. brachycaulos were stored primarily in the cell walls and organelles. After the removal of foliar trichomes of T. brachycaulos, the metal contents on the leaf surface decreased, whereas the contents of most metals inside the leaf increased. This is an evidence that foliar trichomes serve a protective function by intercepting ATM onto the leaf surface.Novelty statementsThere was a significant positive correlation between the contents of 14 trace metals accumulated on the leaf surface and in the leaf of T. brachycaulos, which indicated that atmospheric particulate matters are the main source of trace metals in the leaves.After the removal of foliar trichomes of T. brachycaulos, the trace metal contents on the leaf surface decreased, whereas the contents of most trace metals inside the leaf increased. This is an evidence that foliar trichomes serve a protective function by intercepting atmospheric trace metals onto the leaf surface.


Assuntos
Poluentes Atmosféricos , Metais Pesados , Tillandsia , Oligoelementos , Poluentes Atmosféricos/análise , Biodegradação Ambiental , Monitoramento Ambiental , Metais , Material Particulado , Oligoelementos/análise
10.
An Acad Bras Cienc ; 92(1): e20180813, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32294692

RESUMO

The air quality and distribution of trace elements in a metropolitan area of the Peruvian Andes were evaluated using transplanted epiphytic Tillandsia capillaris as biomonitors. Biomonitors were collected from the non-contaminated area and exposed to five sites with different types of contamination for three months in 2017. After exposure, the content of twenty-one elements were determined by ICP-MS analysis. Datasets were evaluated by one-way ANOVA, exposed-to-baseline (EB), hierarchical cluster analysis (HCA) and principal component analysis (PCA). Results showed significant differences among sampling sites for several elements. According to EF ratios for Ba, Cr, Cu, Pb, Sb, and Zn EB ratios value greater than 1.75 were found around urban areas, indicating anthropogenic influence, which can be attributed to vehicular sources. The highest values of As and Cd were found in areas of agricultural practices, therefore their presence could be related to the employment of agrochemicals (pesticides, herbicides, and phosphate fertilizers). HCA shows that most elements come from vehicular sources and lower from agricultural and natural sources.


Assuntos
Poluição do Ar/análise , Monitoramento Ambiental/métodos , Poluentes Ambientais/análise , Tillandsia/fisiologia , Oligoelementos/análise , Saúde Ambiental , Poluentes Ambientais/efeitos adversos , Nível de Saúde , Humanos , Peru , População Rural , População Urbana
11.
J Hazard Mater ; 393: 122401, 2020 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-32155521

RESUMO

The removal of particulate matters (PM) has emerged as one of the most significant issues in public health and environment worldwide. Environmentalists have proposed the use of indoor air-purifying plants as an eco-friendly strategy to resolve PM-related problems and effectively remove fine particulate matter (PM2.5). Among air-purifying plants, Tillandsia usneoides (L.) L. (T. usneoides) has been used as a biomonitor for heavy metals and air pollutants. However, the PM removal effect of T. usneoides and its primary mechanism remain unclear. Here, we investigated the PM removal performance of T. usneoides in a closed chamber under flow conditions, the effects of trichomes, and the array density according to the different types of PM. The chamber with bulk T. usneoides under flow conditions exhibited 16.5 % and 9.2 % higher removal efficiency in PM2.5T. usneoides for incense and A1 rigid PM, respectively, than that without T. usneoides. T. usneoides with trichome structure exhibited larger removal efficiencies of 7% and 2% in PM2.5 and PM10, respectively, than without trichome for incense particles. In addition, the increase in total effective surface was effective for the deposition of both PM types. The increase in effective surface area by trichome structure and array density of T. usneoides is a crucial factor for the deposition of PM.


Assuntos
Poluentes Atmosféricos/química , Material Particulado/química , Tillandsia , Tricomas , Microscopia Eletrônica de Varredura , Folhas de Planta/anatomia & histologia , Folhas de Planta/química , Folhas de Planta/ultraestrutura , Propriedades de Superfície , Tillandsia/anatomia & histologia , Tillandsia/química , Tillandsia/ultraestrutura , Tricomas/anatomia & histologia , Tricomas/química , Tricomas/ultraestrutura
12.
Nat Commun ; 11(1): 396, 2020 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-31959754

RESUMO

The bromeliad Tillandsia landbeckii thrives in the Atacama desert of Chile using the fog captured by specialized leaf trichomes to satisfy its water needs. However, it is still unclear how the trichome of T. landbeckii and other Tillandsia species is able to absorb fine water droplets during intermittent fog events while also preventing evaporation when the plant is exposed to the desert's hyperarid conditions. Here, we explain how a 5800-fold asymmetry in water conductance arises from a clever juxtaposition of a thick hygroscopic wall and a semipermeable membrane. While absorption is achieved by osmosis of liquid water, evaporation under dry external conditions shifts the liquid-gas interface forcing water to diffuse through the thick trichome wall in the vapor phase. We confirm this mechanism by fabricating artificial composite membranes mimicking the trichome structure. The reliance on intrinsic material properties instead of moving parts makes the trichome a promising basis for the development of microfluidics valves.


Assuntos
Materiais Biomiméticos , Microfluídica/instrumentação , Tillandsia/fisiologia , Tricomas/ultraestrutura , Água/metabolismo , Chile , Clima Desértico , Membranas Artificiais , Microfluídica/métodos , Microscopia de Fluorescência , Folhas de Planta/fisiologia , Folhas de Planta/ultraestrutura , Tillandsia/ultraestrutura , Tricomas/fisiologia
13.
Chemosphere ; 241: 124955, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31604198

RESUMO

Nowadays, atmospheric pollution has a major impact on the human health and the environment, encouraging the development of biomonitors of the air quality over a wide zone. In this study, the relevance of the epiphyte plants Tillandsia usneoides is studied to estimate the transfer of metal(loid)s from a former Zn and Pb mining zone in the Southeast of Spain (Cartagena-La Unión) to the local atmosphere. Biomonitoring was performed by installing plants in 5 sites along a transect from the main mining area to the urban and the coastal zones. An aliquot of plants was collected in every site every 2 months over 1 year. The Tillandsia usneoides have been observed with SEM-EDX, and analysed by ICP-MS to determine trace element concentrations, magnetic susceptibility signals and Zn and Pb isotopes ratios. Results show that atmospheric particles are distributed homogeneously at the plant surface. By comparing elemental contents in Tillandsia usneoides with regard to the values of the geochemical background of the region of Murcia, significant enrichments are observed in the epiphyte plants for Sb, As, Cd, Zn and Pb. The statistical analyses (decentred PCA and PLS) also suggest that the kinetics of dust deposition is slower for the urban and coastal sites compared to the mining sites and highlight an influence of agricultural activities in Cu deposition. The similarity of isotopic compositions (Zn and Pb) between Tillandsia usneoides, soils and atmospheric particles also put in evidence that these plants could be a powerful tool to trace the source of matter in the atmosphere. Finally, this experiment provides new insight to better understand the foliar absorption mechanisms.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Tillandsia/química , Oligoelementos/análise , Poluição do Ar/análise , Atmosfera/análise , Atmosfera/química , Poluição Ambiental/análise , Metais/análise , Mineração , Solo/química , Espanha
14.
Plant Biol (Stuttg) ; 22(2): 243-251, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31736163

RESUMO

Biotic and abiotic interactions are important factors that explain community assembly. For example, epiphytic communities are shaped by tree traits that can act as environmental filters, but also by positive and/or negative interactions among coexisting epiphytes on a tree. Here, we studied interactions among three widespread atmospheric bromeliads with overlapping niches (Tillandsia recurvata, T. tricholepis and T. pohliana), using experimental data about facilitation through seed capture, interspecific interaction during seed germination and competition among adult individuals. We aim to understand how species interactions are reflected in the natural coexisting patterns of epiphytes in communities at high and low tree densities. Tillandsia pohliana showed higher facilitation by capturing almost all wind-dispersing seeds, and had the largest reduction in seed germination in the presence of any adult individual, also presenting a relatively high rate of adult mortality in the presence of other individuals. Our results indicate higher colonisation ability for T. pohliana and distinct strategies of rapid exploitation of T. recurvata and T. tricholepis individuals. In natural communities, the coexistence among atmospheric bromeliads may be hampered by dispersal limitations in wind-dispersed epiphytes at high tree density conditions, but a negative effect of T. recurvata on T. pohliana is still reflected in their reduced coexistence. However, competitive patterns observed in the experimental data may be overshadowed by a possible mass effect driving large communities under such conditions. Our results show the joint effect of positive interactions and high dispersal levels on the community patterns of atmospheric bromeliads.


Assuntos
Estações do Ano , Tillandsia , Sementes , Tillandsia/fisiologia , Árvores , Vento
15.
Physiol Plant ; 168(3): 547-562, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30136347

RESUMO

Climate change is expected to increase the frequency of extreme climatic events, yet few studies have addressed the capacity of plant species to deal with such events. Species that are widespread are predicted to be highly plastic and able to acclimate to highly changing conditions. To study the plasticity in physiological responses of the widely distributed epiphyte Tillandsia utriculata, we transplanted individuals from a coastal scrub and broadleaf evergreen forest to a similar coastal scrub site and forest. After a 45-day acclimation, the plants were moved to a semi-controlled greenhouse at each site, and then subjected to a 20-day drought. Physiological variables were measured during the acclimation and the drought. The individuals of scrub and forest populations had similar relative water content and carbon assimilation in the contrasting conditions of the two transplantation sites despite the high discrepancy between the environments at their original site. Electron transport rates were higher in individuals from the scrub population. Electron transport rates were also higher than estimated from carbon assimilation, suggesting that photorespiration was present. The individuals of the coastal scrub population had a higher capacity to dissipate excess energy this way. The relative distance index of plasticity was high overall, indicating that some traits are highly plastic (titratable acidity, carbon assimilation) in order to maintain the stability of others (maximum quantum yield Fv /Fm and relative water content). We conclude that T. utriculata is a highly plastic species with a high capacity to tolerate extreme environmental changes over a short time.


Assuntos
Mudança Climática , Secas , Estresse Fisiológico , Tillandsia/fisiologia , Carbono/metabolismo , Fotossíntese , Água
16.
Zootaxa ; 4567(2): zootaxa.4567.2.7, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31715900

RESUMO

Bromeliads (Bromeliaceae) are an extremely diverse family of the angiosperms widely distributed in the tropical and subtropical regions of the Americas and West Africa. They often serve as phytotelmata, accumulating rainwater between leaves. Such water reservoirs can be inhabited by diverse organisms. But to date not much attention is paid to inventory of these organisms, with careful identification of each taxon. We found a microcrustacean Disparalona hamata (Birge, 1879) (Crustacea: Cladocera) in the bromeliad Tillandsia aguascalentensis Gardner, 1984 in Mexico. Investigated population included parthenogenetic females, gamogenetic females and males. Hereby the population apparently can pass the full life cycle under conditions of phytotelmata. Along with ecological observations, we provide additional taxonomic notes on the genus Disparalona Fryer, 1968 itself. Recently a series of morphological revisions was conducted for this genus. It was subdivided into two subgenera: Disparalona s.str. and Mixopleuroxus Hudec, 2010. But, in fact, the second taxon is a junior synonym of Leptorhynchus Daday, 1905. In this regard here we provide an updated list of taxonomic synonyms for the subgenus Leptorhynchus.


Assuntos
Bromeliaceae , Cladóceros , Tillandsia , África Ocidental , Animais , Feminino , Masculino , México
17.
Bol. latinoam. Caribe plantas med. aromát ; 18(3): 239-264, mayo 2019. tab, ilus
Artigo em Inglês | LILACS | ID: biblio-1007935

RESUMO

Tillandsia L. genus comprises 649 species, with different uses at different times. T. usneoides L. uses are reported since the late- archaic and pre-Columbian cultures. In XIX-XX centuries, T. usneoides was used in some manufactured products, as polish and packing fruit. Tillandsia has a favorable reputation as medicine: for leucorrhea, rheumatism, ulcers, hemorrhoid treatment, as an anti-diabetic remedy, emetic, analgesic, purgative, contraceptive, antispasmodic and diuretic. Tillandsia chemical composition includes cycloartane triterpenes and hydroxy-flavonoids, which are present in at least 24 species. Several extracts and compounds from Tillandsia spp. have been reported with pharmacological actions, as anti-neoplasia, hypolipidemic, antifungal, anti-HSV-1, hypoglycemic and microbicide. This review communicates the economic importance, ethnobotany, chemistry composition and biological activities of the Tillandsia genus, and analyze its biological and economic perspective. Tillandsia genus has cultural, economic and pharmacological relevance, with a high potential in many essential aspects of the modern society.


El género Tillandsia L. comprende 649 especies, con diferentes usos en diferentes épocas. T. usneoides L. se han reportado desde el arcáico tardío hasta las culturas precolombinas. En los siglos XIX-XX, T. usneoides se usó en productos manufacturados: como abrasivo y embalaje de fruta. Como medicina tradicional, el género Tillandsia se reporta para leucorrea, reumatismo, úlceras, hemorroides, remedio antidiabético, emético, analgésico, purgante, anticonceptivo, antiespasmódico y diurético. Su composición química incluye triterpenos de tipo ciclo-artano e hidroxi-flavonoides, presentes en al menos 24 especies. Los extractos y compuestos del género Tillandsia se han reportado con propiedades antineoplásicas, hipolipidémicas, antifúngicas, anti-HSV-1, hipoglucemiantes y microbicidas. Esta revisión comunica la importancia económica, etnobotánica, composición química y las actividades biológicas del género Tillandsia, y analiza su perspectiva biológica y potencial económica. Tillandsia tiene importancia cultural, económica y farmacológica, con gran potencial en muchos aspectos esenciales de la sociedad moderna.


Assuntos
Plantas Medicinais/química , Extratos Vegetais/química , Etnobotânica , Tillandsia/química , Triterpenos/análise , Extratos Vegetais/farmacologia , Bromeliaceae/química
18.
Braz. j. biol ; 79(2): 201-207, Apr.-June 2019. graf
Artigo em Inglês | LILACS | ID: biblio-989446

RESUMO

Abstract The avoidance of vertebrate herbivory is thought to be one of the possible drivers for the evolution of epiphytism. Scarce literature suggests that epiphyte herbivory is mainly related to insect attack on reproductive structures. In a pine-oak forest we observed almost all inflorescences of an epiphytic bromeliad (Tillandsia carlos-hankii) with signs of florivory; the degree of damage suggested that vertebrate herbivores could be involved. To assess the intensity of vertebrate florivory damage we recorded the percentage of damaged individuals in a 500 m2 plots during two flowering seasons. To identify possible vertebrate herbivores, we installed 20 mixed capture stations, 10 photo-traps focused on bromeliads and analyzed stomach contents of captured vertebrates. Florivory was observed on 62% of individuals during the first flowering season and 77% on the second; and average one individual lost 41% of reproductive structures. Vertebrates associated with florivory were a bird, Icterus bullockii (Aves, Passeriformes, Icteridae), a squirrel Sciurus aureogaster (Mammalia, Rodentia, Sciuridae), and mice, Peromyscus gratus, P. levipes and P. aztecus (Mammalia, Rodentia, Cricetidae). Our results suggest that vascular epiphytes are used as opportunistic resources for small vertebrates during seasons when preferred resources are scarce.


Resumo Acredita-se que a prevenção da herbivoria dos vertebrados é um dos possíveis impulsores da evolução da epífita. A literatura escassa sugere que a herbivora em epífitas está relacionada principalmente ao ataque de insetos as estruturas reprodutivas. Em uma floresta de pinheiros observamos que quase da todas as inflorescências de uma bromélia epífita (Tillandsia carlos-hankii) apresentavam sinais de florivoria; o grau de danos sugeria que herbívoros majores (vertebrados) pudessem estar envolvidos. Para avaliar a intensidade do dano de florivoria de vertebrados, registramos a porcentagem de indivíduos danificados em quadrantes de 500 m2 durante duas estações de florescimento. Para identificar possíveis herbívoros vertebrados, instalamos 20 estações de captura mista e analisamos o conteúdo estomacal de vertebrados capturados. Além disso, foram instaladas 10 foto-armadilhas focadas em bromélias. A florivoria foi observada em 62% dos indivíduos durante a primeira estação de floração e 77% na segunda. Os vertebrados associados à florivoria foram pássaro, Icterus bullockii (Aves, Passeriformes, Icteridae), um esquilo Sciurus aureogaster (Mammalia, Rodentia, Sciuridae) e ratos, Peromyscus gratus, P. levipes e P. aztecus (Mammalia, Rodentia, Cricetidae). Assim, nossos resultados sugerem que epífitas vasculares são usadas como recurso facultativo para estes animais durante as estações, quando os recursos preferidos estão escassos.


Assuntos
Animais , Tillandsia , Inflorescência/fisiologia , Herbivoria/fisiologia , Aves/fisiologia , Mamíferos/fisiologia
19.
Braz J Biol ; 79(2): 201-207, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30066733

RESUMO

The avoidance of vertebrate herbivory is thought to be one of the possible drivers for the evolution of epiphytism. Scarce literature suggests that epiphyte herbivory is mainly related to insect attack on reproductive structures. In a pine-oak forest we observed almost all inflorescences of an epiphytic bromeliad (Tillandsia carlos-hankii) with signs of florivory; the degree of damage suggested that vertebrate herbivores could be involved. To assess the intensity of vertebrate florivory damage we recorded the percentage of damaged individuals in a 500 m2 plots during two flowering seasons. To identify possible vertebrate herbivores, we installed 20 mixed capture stations, 10 photo-traps focused on bromeliads and analyzed stomach contents of captured vertebrates. Florivory was observed on 62% of individuals during the first flowering season and 77% on the second; and average one individual lost 41% of reproductive structures. Vertebrates associated with florivory were a bird, Icterus bullockii (Aves, Passeriformes, Icteridae), a squirrel Sciurus aureogaster (Mammalia, Rodentia, Sciuridae), and mice, Peromyscus gratus, P. levipes and P. aztecus (Mammalia, Rodentia, Cricetidae). Our results suggest that vascular epiphytes are used as opportunistic resources for small vertebrates during seasons when preferred resources are scarce.


Assuntos
Herbivoria/fisiologia , Inflorescência/fisiologia , Tillandsia , Animais , Aves/fisiologia , Mamíferos/fisiologia
20.
Plant Cell Environ ; 42(5): 1645-1656, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30506732

RESUMO

Most epiphytic bromeliads, especially those in the genus Tillandsia, lack functional roots and rely on the absorption of water and nutrients by large, multicellular trichomes on the epidermal surfaces of leaves and stems. Another important function of these structures is the spread of water over the epidermal surface by capillary action between trichome "wings" and epidermal surface. Although critical for the ultimate absorption by these plants, understanding of this function of trichomes is primarily based on light microscope observations. To better understand this phenomenon, the distribution of water was followed by its attenuation of cold neutrons following application of H2 O to the cut end of Tillandsia usneoides shoots. Experiments confirmed the spread of added water on the external surfaces of this "atmospheric" epiphyte. In a morphologically and physiologically similar plant lacking epidermal trichomes, water added to the cut end of a shoot clearly moved via its internal xylem and not on its epidermis. Thus, in T. usneoides, water moves primarily by capillarity among the overlapping trichomes forming a dense indumentum on shoot surfaces, while internal vascular water movement is less likely. T. usneoides, occupying xeric microhabitats, benefits from reduction of water losses by low-shoot xylem hydraulic conductivities.


Assuntos
Tillandsia , Tricomas/fisiologia , Água/fisiologia , Transporte Biológico , Desidratação
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