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1.
PLoS One ; 16(6): e0252790, 2021.
Article in English | MEDLINE | ID: mdl-34166417

ABSTRACT

Vascular epiphytes represent almost 10% of all terrestrial plant diversity. Being structurally dependent on trees, epiphytes live at the interface of vegetation and atmosphere, making them susceptible to atmospheric changes. Despite the extensive research on vascular epiphytes, little is known about wind disturbance on these plants. Therefore, this study investigated the wind-epiphyte mechanical interactions by quantifying the drag forces on epiphytic bromeliads when subjected to increasing wind speeds (5-22 m s-1) in a wind tunnel. Drag coefficients (Cd) and Vogel exponents (B) were calculated to quantify the streamlining ability of different bromeliad species. Bromeliads' reconfiguration occurred first via bending and aligning leaves in the flow direction. Then leaves clustered and reduced the overall plant frontal area. This reconfiguration caused drag forces to increase at a slower rate as wind velocity increased. In the extreme case, drag force was reduced by 50% in a large Guzmania monostachia individual at a wind velocity of 22 m s-1, compared to a stiff model. This species had one of the smallest Cd (0.58) at the highest wind velocity, and the largest negative mean B (-0.98), representing the largest reconfiguration capacity amongst the tested bromeliads. The streamlining ability of bromeliads was mainly restricted by the rigidity of the lower part of the plant where the leaves are already densely clustered. Wind speeds used in this study were generally low as compared to storm force winds. At these low wind speeds, reconfiguration was an effective mechanism for drag reduction in bromeliads. This mechanism is likely to lose its effectiveness at higher wind speeds when continuous vigorous fluttering results in leaf damage and aspects such as root-attachment strength and substrate stability become more relevant. This study is a first step towards an understanding of the mechanical bottleneck in the epiphyte-tree-system under wind stress.


Subject(s)
Adaptation, Physiological/physiology , Bromelia/physiology , Plant Leaves/physiology , Stress, Mechanical , Wind , Algorithms , Bromelia/classification , Models, Theoretical
2.
PLoS One ; 10(12): e0142893, 2015.
Article in English | MEDLINE | ID: mdl-26650515

ABSTRACT

We describe a new treefrog species of Dendropsophus collected on rocky outcrops in the Brazilian Atlantic Forest. Ecologically, the new species can be distinguished from all known congeners by having a larval phase associated with rainwater accumulated in bromeliad phytotelms instead of temporary or lentic water bodies. Phylogenetic analysis based on molecular data confirms that the new species is a member of Dendropsophus; our analysis does not assign it to any recognized species group in the genus. Morphologically, based on comparison with the 96 known congeners, the new species is diagnosed by its small size, framed dorsal color pattern, and short webbing between toes IV-V. The advertisement call is composed of a moderate-pitched two-note call (~5 kHz). The territorial call contains more notes and pulses than the advertisement call. Field observations suggest that this new bromeligenous species uses a variety of bromeliad species to breed in, and may be both territorial and exhibit male parental care.


Subject(s)
Anura/classification , Bromelia/classification , Animals , Bayes Theorem , Brazil , Forests , Male , Phylogeny
3.
Int J Mol Sci ; 13(5): 6040-6052, 2012.
Article in English | MEDLINE | ID: mdl-22754348

ABSTRACT

Bromeliads are of great economic importance in flower production; however little information is available with respect to genetic characterization of cultivated bromeliads thus far. In the present study, a selection of cultivated bromeliads was characterized via inter-simple sequence repeat (ISSR) markers with an emphasis on genetic diversity and population structure. Twelve ISSR primers produced 342 bands, of which 287 (~84%) were polymorphic, with polymorphic bands per primer ranging from 17 to 34. The Jaccard's similarity ranged from 0.08 to 0.89 and averaged ~0.30 for the investigated bromeliads. The Bayesian-based approach, together with the un-weighted paired group method with arithmetic average (UPGMA)-based clustering and the principal coordinate analysis (PCoA), distinctly grouped the bromeliads from Neoregelia, Guzmania, and Vriesea into three separately clusters, well corresponding with their botanical classifications; whereas the bromeliads of Aechmea other than the recently selected hybrids were not well assigned to a cluster. Additionally, ISSR marker was proven efficient for the identification of hybrids and bud sports of cultivated bromeliads. The findings achieved herein will further our knowledge about the genetic variability within cultivated bromeliads and therefore facilitate breeding for new varieties of cultivated bromeliads in future as well.


Subject(s)
Bromelia/classification , Bromelia/genetics , Microsatellite Repeats , Bayes Theorem , Breeding , DNA, Plant/genetics , Genetic Variation , Phylogeny , Plant Leaves/genetics
4.
Braz J Biol ; 72(2): 337-41, 2012 May.
Article in English | MEDLINE | ID: mdl-22735142

ABSTRACT

The presence of lizards in bromeliads has been widely documented. Nevertheless, the possibility of some type of preference or specificity among lizards for particular bromeliad species has not yet been investigated. Therefore, this study aims to document the presence of Abronia oaxacae in six species of tank bromeliads found in pine forests, pine-live oak forests, and live oak groves during both the rainy season and the dry season. Three adult individuals of Abronia oaxacae were collected; one in a Tillandsia violácea (pine-live oak forest), one in a T. calothyrsus (live oak grove), and one in a T. prodigiosa (live oak grove). All three specimens were collected in sampling efforts carried out during the dry season. The results of the present study suggest that A. oaxacae shows no preference for a single, specific bromeliad species, although it does have a certain preference for a few select species. The presence of A. oaxacae in bromeliads during the dry season could be related to the cooler, moister microhabitat that these plants represent.


Subject(s)
Bromelia/classification , Ecosystem , Lizards/physiology , Animals , Lizards/classification , Mexico , Seasons , Trees
5.
Braz. j. biol ; 72(2): 337-341, May 2012. ilus, tab
Article in English | LILACS | ID: lil-639443

ABSTRACT

The presence of lizards in bromeliads has been widely documented. Nevertheless, the possibility of some type of preference or specificity among lizards for particular bromeliad species has not yet been investigated. Therefore, this study aims to document the presence of Abronia oaxacae in six species of tank bromeliads found in pine forests, pine-live oak forests, and live oak groves during both the rainy season and the dry season. Three adult individuals of Abronia oaxacae were collected; one in a Tillandsia violácea (pine-live oak forest), one in a T. calothyrsus (live oak grove), and one in a T. prodigiosa (live oak grove). All three specimens were collected in sampling efforts carried out during the dry season. The results of the present study suggest that A. oaxacae shows no preference for a single, specific bromeliad species, although it does have a certain preference for a few select species. The presence of A. oaxacae in bromeliads during the dry season could be related to the cooler, moister microhabitat that these plants represent.


A presença de lagartos em bromélias tem sido amplamente documentada, no entanto, a possibilidade de algum tipo de preferência ou especificidade entre os lagartos para determinadas espécies de bromélias ainda não foi investigada. Portanto, este estudo tem como objetivo documentar a presença de Abronia oaxacaeem seis espécies de bromélias tanque encontrado em pinhais, matas de pinheiro e carvalho vivo, e os bosques de carvalho vivo, durante a estação chuvosa ea estação seca. Três indivíduos adultos de Abronia oaxacaeforam coletados, um em Tillandsia violácea (floresta de pinheiro e carvalho ao vivo), um em T. calothyrsus(bosque de carvalhos vivos), e um em T. prodigiosa (bosque de carvalhos vivos). Todas as três amostras foram coletadas em amostragem esforços realizados durante a estação seca. Os resultados do estudo sugerem que A. oaxacaenão apresenta preferência por um único, específico espécies de bromélias, apesar de não apresentar certa preferência por algumas espécies selecionadas. A presença de A. oaxacae em bromélias durante a estação seca pode estar relacionada com o condições úmidas e frias oferecidas por estas plantas.


Subject(s)
Animals , Bromelia/classification , Ecosystem , Lizards/physiology , Lizards/classification , Mexico , Seasons , Trees
6.
Biota neotrop. (Online, Ed. port.) ; 9(1): 73-79, Jan.-Mar. 2009. graf, mapas, tab
Article in Portuguese | LILACS | ID: lil-518432

ABSTRACT

Vascular epiphytes are frequent in mesic habitats and mid-elevation regions. The present study investigated the diversity and species composition of epiphytic bromeliads in the Natural Reserve of Serra do Teimoso (RNST) located in a transitional area between ombrophilous and semideciduous forests. Adapted from the "Rapid and Representative Sampling of Vascular and Non-vascular epiphyte Diversity of Tropical Rain Forests" protocol, our survey method used eight phorophytes of Cariniana legalis (Martius) Kuntze found between 284 and 573 m a.s.l.. We registered 19 morphospecies and 526 bromeliad groups. Almost one third of the species were classified as widely distributed and 27.3% are endemic to southern Bahia. Shannon index was 2.2 nats.ind-1 and the estimated number of species in this area was 25 (SD = ± 3.5). Most C. legalis harbored a similar abundance and species composition of epiphytes, which was dominated by Hohenbergia and Aechmea species. This study registered the occurrence of three species that are new to the state of Bahia, and one genus was collected for the first time in the RNST. Results are in accordance with the known pattern of lower epiphytic diversity in drier locations. Since all new records are exclusive to the crowns of large trees, the sampling of these new records was only possible because climbing techniques were used. Compared to other methodologies for floristic surveys, the one employed here demanded lower sample effort and yielded similar results. Large trees play an important role for epiphytes due to the concentration of species and individuals on them. Thus, the utilization of canopy methodologies in other field surveys would be desirable to sample appropriately epiphytes in large trees.


Subject(s)
Biodiversity , Bromelia/classification , Bromelia/growth & development , Ecosystem/analysis , Ecosystem/classification , Ecosystem/adverse effects , Trees
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