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1.
Braz J Biol ; 83: e278315, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38422271

RESUMO

Understanding the distribution and demographic structure of populations is essential for species conservation. In Brazil, the rheophyte group has been greatly affected by the construction of hydroelectric dams. All know populations of Dyckia brevifolia Baker along Itajaí-Açu River were studied. The plants were classified as seedlings, immature or reproductive rosettes. In addition, the number of dead rosettes, except for seedlings, was determined in five populations of D. brevifolia. The total number of rosettes per population ranged from 273 to 7,185, totaling 30,443 rosettes, and 1,789 seedlings (5.9%). Only 2.4% of rosettes occurred isolated and 97.6% occurred clumped into 2,254 clumps. The number of rosettes per clump ranged from two to 339 rosettes. The percentage of reproductive rosettes per population ranged from 7.8 to 26.7%. The correlation between the number of clumps or between the total number of rosettes and the area of occupation was significant and positive (r = 0.82; P < 0.05). The production of offshoots (1-4) occurred on immature and reproductive rosettes. Dyckia brevifolia has herbivory by Hydrochaeris hydrochaeris (capybara). These rosettes die or often resprout, emitting from 1 to 20 shoots. The populations did not present a pattern of distribution of rosettes in the diametric classes, but in all populations a decrease in the number of rosettes can be observed in the classes with the largest diameter. The small area of occupation (9,185 m2) showed high environmental specificity and vulnerable to habitat loss and environmental changes. Therefore, the maintenance these sites is essential for the long-term conservation of D. brevifolia.


Assuntos
Bromeliaceae , Animais , Brasil , Rios/química , Roedores , Demografia
2.
Methods Mol Biol ; 2759: 131-136, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38285145

RESUMO

The main difficulty for the cultivation and conservation of bromeliad species is the reduced number of propagules and slow growth of many of the species, resulting in a low propagation efficiency. Bromeliad plants are hardy and relatively easy to cultivate, with a high ornamental and ecological importance. Aiming at efficient micropropagation rates of V. hieroglyphica, a highly valued bromeliad, with very low propagation efficiency, a temporary immersion system was used and compared to semisolid and liquid static medium. Cultures obtained from in vitro germinated seeds were used as explants, maintaining their genetic diversity. Micropropagation with this simple temporary immersion system, composed of two autoclavable flasks, each with one opening for the attachment of 22 µm syringe filters, connected by a rubber stopper and an inner glass tube. In the bottom flask, an air valve is attached to the filter, which is subsequently connected to an aquarium pump and a timer and plugged to an outlet. This simple temporary immersion system showed improved micropropagation efficiency and is a method that can also be evaluated for other species.


Assuntos
Bromeliaceae , Imersão , Cateteres , Reprodução , Sementes
3.
Plant Biol (Stuttg) ; 26(2): 188-196, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38168064

RESUMO

Stress memory is the development of altered responses to stress due to previous exposure, which might result in increased tolerance. Biochemical and physiological parameters shown to be positively affected by stress memory include those of the antioxidant and nitrosative metabolism, photosynthetic pigments and osmolyte content. Epiphytic bromeliads likely present stress memory since they experience frequent droughts in the canopies. Thus, we aimed to evaluate if the epiphytic bromeliad Acanthostachys strobilacea (Schult. & Schult.f.) Klotzsch shows improved metabolic stress defence responses to a second drought and rewatering cycle compared to a single exposure. In a controlled environment chamber, 90-day-old plants were exposed to one or two drought-rewatering cycles of 14 days without irrigation and 5 days of rewatering each. Sampling occurred after the final drought and rewatering periods for one or two cycles treatments. The free amino acid, chlorophyll, and carotenoid levels and S-nitrosoglutathione reductase (GSNOR) activity were higher at the second drought than at the first exposure. The rise in nocturnal acidification (indicative of increased CAM activity) caused by the initial drought persisted through the second drought-rewatering cycle, implying a lasting memory effect on CAM activity. Furthermore, the second recovery did not induce glutathione accumulation, as in the first rewatering event, suggesting the pre-exposure to drought reduced this thiol's demand during a later recovery. Our results evidence metabolic changes related to drought stress memory in A. strobilacea, supporting this mechanism might be involved in the tolerance of epiphytic bromeliads to intermittent droughts.


Assuntos
Bromeliaceae , Secas , Água/metabolismo , Folhas de Planta/metabolismo , Fotossíntese , Clorofila/metabolismo , Bromeliaceae/metabolismo
4.
Braz. j. biol ; 84: e255529, 2024. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1364534

RESUMO

Reports from popular medicine usually act as a basis for the development of new drugs from natural compounds with therapeutic actions for serious diseases and prevalence such as cancer. Bromelia antiacantha Bertol. is a species of the Bromeliaceae family, considered an unconventional food plant, found in the south and midwest regions of Brazil. Despite the high nutritional content and pharmacological potential of its fruits, few scientific studies report its biological actions. Thus, this study evaluates the phytochemical profile of aqueous and ethanol extracts obtained from B. antiacantha fruits, as well as their possible antioxidant, antitumor, and cytotoxic activities. The aqueous extract exhibited phenolic compounds and flavonoids, while ethanol extracts indicated the presence of flavonoids and coumarin in their composition, regardless of the region of collection. The ethanolic extract demonstrated a more promising antioxidant effect than the aqueous extract and also induced a significant inhibition in the viability of human cervical cancer cells of the SiHa strain. In addition, treatment with both extracts did not alter the viability of non-tumor cells of the immortalized human keratinocyte lineage (HaCaT). These results bring new data about extracts obtained from a native plant, edible and traditionally used in popular medicine, opening new perspectives for its possible therapeutic application.


Relatos da medicina popular costumam atuar como referencial para o desenvolvimento de novos fármacos a partir de moléculas naturais com ações terapêuticas para doenças de alta gravidade e prevalência como o câncer. Bromelia antiacantha Bertol. é uma espécie da família Bromeliaceae, considerada uma planta alimentícia não convencional (PANC), encontrada nas regiões sul e centro-oeste do Brasil. Apesar do alto teor nutritivo e potencial farmacológico de seus frutos, poucos estudos científicos relatam suas ações biológicas. Desta forma, este estudo avalia o perfil fitoquímico de extratos aquoso e etanólico obtidos de frutos de B. antiacantha, bem como a sua possível ação antioxidante, antitumoral e citotóxica. O extrato aquoso apresentou compostos fenólicos e flavonoides, enquanto os extratos etanólicos apontam a presença de flavonóides e cumarina em sua composição, independente da região de coleta. O extrato etanólico demonstrou efeito antioxidante mais promissor do que o extrato aquoso e também induziu uma inibição significativa na viabilidade de células humanas de câncer cervical da linhagem SiHa. Além disso, o tratamento com ambos extratos não alterou a viabilidade de células não tumorais da linhagem de queratinócitos humanos imortalizados (HaCaT). Estes dados trazem novas informações sobre extratos obtidos de uma espécie vegetal nativa, comestível e já utilizada tradicionalmente, mas abrindo novas perspectivas quanto a possíveis aplicações terapêuticas.


Assuntos
Flavonoides , Neoplasias do Colo do Útero , Bromeliaceae , Bromelia , Usos Terapêuticos , Compostos Fitoquímicos , Fitoterapia
5.
Ann Bot ; 132(3): 443-454, 2023 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-37647886

RESUMO

BACKGROUND AND AIMS: Phenotypic plasticity allows plants to cope with environmental variability. Plastic responses to the environment have mostly been investigated at the level of individuals (plants) but can also occur within leaves. Yet the latter have been underexplored, as leaves are often treated as functional units with no spatial structure. We investigated the effect of a strong light gradient on plant and leaf traits and examined whether different portions of a leaf show similar or differential responses to light intensity. METHODS: We measured variation in 27 morpho-anatomical and physiological traits of the rosette and leaf portions (i.e. base and apex) of the tank bromeliad Aechmea aquilega (Bromeliaceae) when naturally exposed to a marked gradient of light intensity. KEY RESULTS: The light intensity received by A. aquilega had a strong effect on the structural, biochemical and physiological traits of the entire rosette. Plants exposed to high light intensity were smaller and had wider, shorter, more rigid and more vertical leaves. They also had lower photosynthetic performance and nutrient levels. We found significant differences between the apex and basal portions of the leaf under low-light conditions, and the differences declined or disappeared for most of the traits as light intensity increased (i.e. leaf thickness, adaxial trichome density, abaxial and adaxial trichome surface, and vascular bundle surface and density). CONCLUSIONS: Our results reveal a strong phenotypic plasticity in A. aquilega, particularly in the form of a steep functional gradient within the leaf under low-light conditions. Under high-light conditions, trait values were relatively uniform along the leaf. This study sheds interesting new light on the functional complexity of tank bromeliad leaves, and on the effect of environmental conditions on leaf trait regionalization.


Assuntos
Adaptação Fisiológica , Folhas de Planta , Bromeliaceae , Fotossíntese , Folhas de Planta/fisiologia , Plantas
6.
Braz J Biol ; 83: e273906, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37436193

RESUMO

Studies on the germination and establishment of plants are key pieces to understanding the reproductive success of plants. This work aimed to describe in vitro germination and reserve mobilization in the bromeliad Vriesea friburgensis through morphological, histochemical, and biochemical analysis. The conditions used in this study for the in vitro germination are adequate. From the third day of in vitro inoculation, a uniform germination of 98% was obtained, exhibiting a high physiological quality of the seeds and a high potential to produce seedlings (94%). There is early reserve mobilization, which began in the imbibition phase. The accumulated reserves in the endosperm cytoplasm are degraded by hydrolytic enzymes provided by the aleurone layer. It is possible that compounds in the cell walls of the endosperm contribute to a lesser extent in mobilization. Additionally, it was observed that starch accumulation in the cotyledon increases when the seedling has formed. Results from this study provide insights for future studies on ecology, seed technology, and conservation in this species. This study contributes to the limited knowledge of the dynamics of reserves during germination and seedling establishment in Bromeliaceae. To the best of our knowledge, this is the first study with this approach in the genus Vriesea.


Assuntos
Bromeliaceae , Germinação , Germinação/fisiologia , Plântula/fisiologia , Sementes/fisiologia , Cotilédone/metabolismo
7.
Braz J Microbiol ; 54(3): 1885-1897, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37322328

RESUMO

The phytotelmata is a water-filled tank on a terrestrial plant, and it plays an important role in bromeliad growth and ecosystem functioning. Even though previous studies have contributed to elucidate the composition of the prokaryotic component of this aquatic ecosystem, its mycobiota (fungal community) is still poorly known. In the present work, ITS2 amplicon deep sequencing was used to examine the fungal communities inhabiting the phytotelmata of two bromeliads species that coexist in a sun-exposed rupestrian field of Southeastern Brazil, namely Aechmea nudicaulis (AN) and Vriesea minarum (VM). Ascomycota was the most abundant phylum in both bromeliads (57.1 and 89.1% in AN and VM respectively, on average), while the others were present in low abundance (< 2%). Mortierellomycota and Glomeromycota were exclusively observed in AN. Beta-diversity analysis showed that samples from each bromeliad significantly clustered together. In conclusion, despite the considerable within-group variation, the results suggested that each bromeliad harbor a distinct fungi community, what could be associated with the physicochemical characteristics of the phytotelmata (mainly total nitrogen, total organic carbon, and total carbon) and plant morphological features.


Assuntos
Bromeliaceae , Ecossistema , Brasil , Bromeliaceae/microbiologia , Água , Carbono
8.
Braz J Biol ; 84: e270998, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37162122

RESUMO

Urban ecosystems could jeopardize the existence of vascular epiphytes (VE) given that their occurrence is linked to phorophyte availability and particular climatic conditions. Despite reports of VE in cities, nothing is known about their demography. A first step in this direction is to describe their population structures (PS). We established the PS of VE present in urban parks in Oaxaca City (Mexico), addressing the following questions: 1) what is their demographic status? and 2) are there differences in the structure of populations growing in native versus exotic phorophytes? During 2021, we censused all the trees in six urban parks, recording their origin (native or exotic), the epiphytic species found on them and the development stages present in each VE population. Overall, five VE species were documented: Tillandsia ionantha, T. makoyana, T. sp., T. schiedeana and T. recurvata (Bromeliaceae); the first three with only one individual and the latter two with 95 and 5,694, respectively. A MANOVA test indicated significant differences in PS between T. recurvata (type I structure, suggesting a growing population) and T. schiedeana (type III structure, suggesting a senile population) (Wilkes' λ= 0.821, F-Radio= 11.96 P<0.001). PS showed no differences related to tree origin. Our results indicate that it is necessary to conduct demographic studies to have a more accurate idea of the current condition of vascular epiphytes in cities. For instance, even though we found five VS species, only one of them seems to have viable populations in Oaxaca city.


Assuntos
Bromeliaceae , Ecossistema , Cidades , México , Árvores , Demografia
9.
PeerJ ; 11: e14624, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36647445

RESUMO

Salt stress is one of the most severe abiotic stresses affecting plant growth and development. The application of silicon (Si) is an alternative that can increase the tolerance of plants to various types of biotic and abiotic stresses. The objective was to evaluate salt stress's effect in vitro and Si's mitigation potential on Aechmea blanchetiana plants. For this purpose, plants already established in vitro were transferred to a culture medium with 0 or 14 µM of Si (CaSiO3). After growth for 30 days, a stationary liquid medium containing different concentrations of NaCl (0, 100, 200, or 300 µM) was added to the flasks. Anatomical and physiological analyses were performed after growth for 45 days. The plants cultivated with excess NaCl presented reduced root diameter and effective photochemical quantum yield of photosystem II (PSII) (ΦPSII) and increased non-photochemical dissipation of fluorescence (qN). Plants that grew with the presence of Si also had greater content of photosynthetic pigments and activity of the enzymes of the antioxidant system, as well as higher values of maximum quantum yield of PSII (FV/FM), photochemical dissipation coefficient of fluorescence (qP) and fresh weight bioaccumulation of roots and shoots. The anatomical, physiological and biochemical responses, and growth induced by Si mitigated the effect of salt stress on the A. blanchetiana plants cultivated in vitro, which can be partly explained by the tolerance of this species to grow in sandbank (Restinga) areas.


Assuntos
Bromeliaceae , Cloreto de Sódio , Cloreto de Sódio/farmacologia , Silício/farmacologia , Bromeliaceae/metabolismo , Fotossíntese , Complexo de Proteína do Fotossistema II/metabolismo
10.
Photochem Photobiol ; 99(3): 1028-1036, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36177611

RESUMO

The use of sunscreen is one of the photoprotection measures most used by the population, so these products must offer broad-spectrum protection against UVA and UVB radiation. Encholirium spectabile, popularly known as "macambira-de-flecha," is a species characterized by its rocky outcrops and found in the Caatinga. This biome is known for extreme droughts and dry periods, and for this reason, its vegetation needed to develop resistance mechanisms. The aim of this work was to evaluate the use of E. spectabile incorporated in O/W emulsion as a potential photoprotective agent and their antioxidant activity. Four chemical constituents (ferulic acid, caffeic acid, p-coumaric acid and apigenin) were identified by HPLC-DAD analysis, and emulsions containing different concentrations (1%, 2.5% and 5%) of the extract without and with the addition of chemical filters (octyl methoxycinnamate and benzophenone-3) were prepared and submitted to the test of preliminary stability. The Q formulation demonstrated little variation in the preliminary stability test and was selected for estimated your protection against UVB and determination of in vitro protection factor UVA. The formulations remained stable during the freeze-thaw cycle; the extract despite maintaining the UVA-PF and decreasing the wavelength showed an increase in FPS from 14.4 (control) to 18.8 (control+ Es-HA80).


Assuntos
Bromeliaceae , Bromeliaceae/química , Emulsões , Raios Ultravioleta , Protetores Solares/farmacologia , Protetores Solares/química
11.
Am J Bot ; 110(1): e16104, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36571428

RESUMO

PREMISE: The consequences of acidity for plant performance are profound, yet the prevalence and causes of low pH in bromeliad tank water are unknown despite its functional relevance to key members of many neotropical plant communities. METHODS: We investigated tank water pH for eight bromeliad species in the field and for the widely occurring Guzmania monostachia in varying light. We compared pH changes over time between plant and artificial tanks containing a solution combined from several plants. Aquaporin transcripts were measured for field plants at two levels of pH. We investigated relationships between pH, leaf hydraulic conductance, and CO2 concentration in greenhouse plants and tested proton pump activity using a stimulator and inhibitor. RESULTS: Mean tank water pH for the eight species was 4.7 ± 0.06 and was lower for G. monostachia in higher light. The pH of the solution in artificial tanks, unlike in plants, did not decrease over time. Aquaporin transcription was higher for plants with lower pH, but leaf hydraulic conductance did not differ, suggesting that the pH did not influence water uptake. Tank pH and CO2 concentration were inversely related. Fusicoccin enhanced a decrease in tank pH, whereas orthovanadate did not. CONCLUSIONS: Guzmania monostachia acidified its tank water via leaf proton pumps, which appeared responsive to light. Low pH increased aquaporin transcripts but did not influence leaf hydraulic conductance, hence may be more relevant to nutrient uptake.


Assuntos
Aquaporinas , Bromeliaceae , Dióxido de Carbono/metabolismo , Folhas de Planta/metabolismo , Água/metabolismo , Aquaporinas/genética
12.
Commun Biol ; 5(1): 920, 2022 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-36071139

RESUMO

Aechmea fasciata is one of the most popular bromeliads and bears a water-impounding tank with a vase-like rosette. The tank habit is a key innovation that has promoted diversity among bromeliads. To reveal the genomic basis of tank habit formation and ethylene-induced flowering, we sequenced the genome of A. fasciata and assembled 352 Mb of sequences into 24 chromosomes. Comparative genomic analysis showed that the chromosomes experienced at least two fissions and two fusions from the ancestral genome of A. fasciata and Ananas comosus. The gibberellin receptor gene GID1C-like was duplicated by a segmental duplication event. This duplication may affect GA signalling and promote rosette expansion, which may permit water-impounding tank formation. During ethylene-induced flowering, AfFTL2 expression is induced and targets the EIN3 binding site 'ATGTAC' by AfEIL1-like. The data provided here will serve as an important resource for studying the evolution and mechanisms underlying flowering time regulation in bromeliads.


Assuntos
Ananas , Bromeliaceae , Bromeliaceae/metabolismo , Etilenos/metabolismo , Hábitos , Água/metabolismo
13.
An Acad Bras Cienc ; 94(3): e20210894, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35920488

RESUMO

Temporary waters are common environments found in physical and biological substrates. Among them, some bromeliads species are known to hold water in their tanks, in a habitat called phytotelmata. Phytotelmata serve as habitats for several organisms, from bacteria and protists to arthropods and anurans. Peritrich ciliates are often found as epibionts on aquatic invertebrates in these environments. Here, we report two cases of epibiosis involving Lagenophrys sp. attached to ostracods (Elpidium spp.) and Rhabdostyla sp. colonizing hydrachnid mites in the tanks of two bromeliad species. In our analysis, we measured the frequency of epibiosis considering the presence of both basibiont and epibiont in the samples. The results shown a significant difference between Elpidium sp. and Lagenophrys sp. compared to hydrachnid mites and Rhabdostyla sp. (87.5% and 19%, respectively), supported by the Kruskal-Walis test (p = 0.0003, Chi-square = 9.687). These reports are important since the knowledge of phytotelmata communities from tropical and subtropical areas is incipient, although it has been increasing over the last years. It also shows that epibiosis doesn't always represent a beneficial relationship. These two epibiosis systems found in bromeliad tanks raise questions about organism's dispersal throughout other phytotelmata and other temporary water habitats.


Assuntos
Bromeliaceae , Cilióforos , Ácaros , Animais , Brasil , Crustáceos , Invertebrados , Água
14.
Yeast ; 39(6-7): 363-400, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35715939

RESUMO

The plant phyllosphere is one of the largest sources of microorganisms, including yeasts. In bromeliads, the knowledge of yeasts is dispersed and still incipient. To understand the extent of our knowledge of the subject, this review proposes to compile and synthesize existing knowledge, elucidating possible patterns, biotechnological and taxonomic potentials, bringing to light new knowledge, and identifying information gaps. For such, we systematically review scientific production on yeasts in bromeliads using various databases. The results indicated that the plant compartments flowers, fruits, leaves, and water tank (phytotelma) have been studied when focusing on the yeast community in the bromeliad phyllosphere. More than 180 species of yeasts and yeast-like fungi were recorded from the phyllosphere, 70% were exclusively found in one of these four compartments and only 2% were shared among all. In addition, most of the community had a low frequency of occurrence, and approximately half of the species had a single record. Variables such as bromeliad subfamilies and functional types, as well as plant compartments, were statistically significant, though inconclusive and with low explanatory power. At least 50 yeast species with some biotechnological potentials have been isolated from bromeliads. More than 90% of these species were able to produce extracellular enzymes. In addition, other biotechnological applications have also been recorded. Moreover, new species have been described, though yeasts were only exploited in approximately 1% of the existing bromeliads species, which highlights that there is still much to be explored. Nevertheless, it appears that we are still far from recovering the completeness of the diversity of yeasts in this host. Furthermore, bromeliads proved to be a good ecological model for prospecting new yeasts and for studies on the interaction between plants and yeasts. In addition, the yeast community diverged among plant compartments, establishing bromeliads as a microbiologically complex and heterogeneous mosaic.


Assuntos
Bromeliaceae , Bromeliaceae/microbiologia , Flores , Plantas , Água , Leveduras
15.
J Hazard Mater ; 437: 129314, 2022 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-35728311

RESUMO

Due to the increasing evidence of widespread plastic pollution in the air, the impact on plants of airborne particles of polycarbonate (PC), polyethyleneterephthalate (PET), polyethylene (PE), and polyvinylchloride (PVC) was tested by administering pristine and aged airborne micro-nanoplastics (MNPs) to Tillandsia usneoides for two weeks. Here we showed that exposure to pristine MNPs, significantly reduced plant growth with respect to controls. Particularly, PVC almost halved plant development at the end of the treatment, while the other plastics exerted negative effects on growth only at the beginning of the exposure, with final stages comparable to those of controls. Plants exposed to aged MNPs showed significantly decreased growth at early stages with PC, later in the growth with PE, and even later with PET. Aged PVC did not exert a toxic effect on plants. When present, the plastic-mediated reduction in plant growth was coupled with a decrease in photosynthetic activity and alterations in the plant concentration of macro- and micronutrients. The plastic particles were showed to adhere to the plant surface and, preferentially, on the trichome wings. Our results reported, for the first time, evidence of negative effects of airborne plastic pollution on plant health, thus raising concerns for related environmental risks.


Assuntos
Bromeliaceae , Tillandsia , Animais , Monitoramento Ambiental/métodos , Microplásticos , Plásticos/toxicidade , Cloreto de Polivinila/toxicidade
16.
Naturwissenschaften ; 109(3): 28, 2022 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-35575831

RESUMO

Nectar plays important roles in the relationship between plants and other organisms, both within pollination systems and as a defense mechanism. In the latter case, extranuptial nectaries (ENNs) usually attract patrolling arthropods that reduce herbivory. ENNs have been frequently reported within the "xeric clade" of Bromeliaceae, but their occurrence in other groups of bromeliads is largely unexplored, especially considering their position, secretory activity and structure. After observing the presence of ants constantly patrolling the inflorescences of Pitcairnia burchellii Mez, we searched for the presence, secretory activity, and structure of ENNs in this species. We also provide a brief review of the occurrence ENNs in Bromeliaceae. The distribution of nectaries was assessed using ant-exclusion experiments, while structural analysis was performed using standard methods for light and scanning electron microscopy. The presence of sugars in the secretion was assessed by thin-layer chromatography and glucose strip tests. Nectaries in P. burchelli are non-structured glands on the adaxial surface of floral bracts and sepals. Bracts and sepals are distinct spatial units that act over time in the same strategy of floral bud protection. Literature data reveals that ENNs might be more common within Bromeliaceae than previously considered, comprising a homoplastic feature in the family. Future perspectives and evolutionary and taxonomic implications are discussed.


Assuntos
Formigas , Bromeliaceae/fisiologia , Néctar de Plantas , Animais , Artrópodes/fisiologia , Bromeliaceae/ultraestrutura , Cromatografia em Camada Delgada , Mecanismos de Defesa , Herbivoria , Microscopia Eletrônica de Varredura , Néctar de Plantas/química , Polinização/fisiologia
17.
PeerJ ; 10: e12706, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35127281

RESUMO

BACKGROUND: Pseudalcantarea grandis (Schltdl.) Pinzón & Barfuss is a tank bromeliad that grows on cliffs in the southernmost portion of the Chihuahuan desert. Phytotelmata are water bodies formed by plants that function as micro-ecosystems where bacteria, algae, protists, insects, fungi, and some vertebrates can develop. We hypothesized that the bacterial diversity contained in the phytotelma formed in a bromeliad from an arid zone would differ in sites with and without surrounding vegetation. Our study aimed to characterize the bacterial composition and putative metabolic functions in P. grandis phytotelmata collected in vegetated and non-vegetated sites. METHODS: Water from 10 individuals was sampled. Five individuals had abundant surrounding vegetation, and five had little or no vegetation. We extracted DNA and amplified seven hypervariable regions of the 16S gene (V2, V4, V8, V3-6, 7-9). Metabarcoding sequencing was performed on the Ion Torrent PGM platform. Taxonomic identity was assigned by the binning reads and coverage between hit and query from the reference database of at least 90%. Putative metabolic functions of the bacterial families were assigned mainly using the FAPROTAX database. The dominance patterns in each site were visualized with rank/abundance curves using the number of Operational Taxonomic Units (OTUs) per family. A percentage similarity analysis (SIMPER) was used to estimate dissimilarity between the sites. Relationships among bacterial families (identified by the dominance analysis and SIMPER), sites, and their respective putative functions were analyzed with shade plots. RESULTS: A total of 1.5 million useful bacterial sequences were obtained. Sequences were clustered into OTUs, and taxonomic assignment was conducted using BLAST in the Greengenes databases. Bacterial diversity was 23 phyla, 52 classes, 98 orders, 218 families, and 297 genera. Proteobacteria (37%), Actinobacteria (19%), and Firmicutes (15%) comprised the highest percentage (71%). There was a 68.3% similarity between the two sites at family level, with 149 families shared. Aerobic chemoheterotrophy and fermentation were the main metabolic functions in both sites, followed by ureolysis, nitrate reduction, aromatic compound degradation, and nitrogen fixation. The dominant bacteria shared most of the metabolic functions between sites. Some functions were recorded for one site only and were related to families with the lowest OTUs richness. Bacterial diversity in the P. grandis tanks included dominant phyla and families present at low percentage that could be considered part of a rare biosphere. A rare biosphere can form genetic reservoirs, the local abundance of which depends on external abiotic and biotic factors, while their interactions could favor micro-ecosystem resilience and resistance.


Assuntos
Bromeliaceae , Ecossistema , Animais , Humanos , Bromeliaceae/genética , Filogenia , Bactérias/genética , Água , Plantas
18.
Artigo em Inglês | MEDLINE | ID: mdl-35225759

RESUMO

Eight yeast isolates with an affinity to the genus Tremella were obtained from bromeliads from different locations in Brazil. Although the formation of basidia and basidiocarp were not observed, on the basis of the results of sequence analysis of the D1/D2 domain of the large subunit (LSU) rRNA gene and internal transcribed spacer (ITS) region, we suggest that these isolates represent two novel species of the genus Tremella. These yeasts are phylogenetically related to Tremella saccharicola and Tremella globispora. Therefore, we propose Tremella ananatis sp. nov. and Tremella lamprococci sp. nov. as novel yeast species of the order Tremellales (Agaricomycotina, Basidiomycota). Sequence analysis revealed that Tremella ananatis sp. nov. differs by 11 and 28 nucleotide substitutions from Tremella saccharicola in the D1/D2 sequence and ITS region, respectively. Moreover, Tremella lamprococci sp. nov. differs by 15 and 29 nucleotide substitutions from Tremella globispora in the D1/D2 sequence and ITS region, respectively. The holotypes of Tremella ananatis sp. nov. and Tremella lamprococci sp. nov. are CBS 14568T and CBS 14567T, and the MycoBank numbers are MB840480 and MB840481, respectively.


Assuntos
Basidiomycota , Bromeliaceae/microbiologia , Filogenia , Composição de Bases , Basidiomycota/classificação , Basidiomycota/isolamento & purificação , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Técnicas de Tipagem Micológica , Análise de Sequência de DNA
19.
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
20.
An Acad Bras Cienc ; 93(suppl 4): e20200973, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34730616

RESUMO

Hohenbergia lanata Pereira & Moutinho is an endemic bromeliad of the State of Bahia (Brazil), occurring in an altitudinal transition forest between Caatinga dry woodland and Atlantic Forest. The type material was collected by Roberto Burle-Marx, who introduced it into cultivation in his gardens, but lacking the accurate provenance, only mentioning that it was collected between Milagres and Amargosa municipalities. It was later described by Pereira & Moutinho based on a cultivated specimen. In this work, we present new specimens found in natural populations in an area that coincides with the type locality description, enabling us to expand the description of the species, as well as to provide images of the living plants in the field, adding information about its habitat. The herbarium collections revision and the new population found in the field enabled us to propose an updated conservation status and to better characterize the habit, plant architecture, and to add new morphological comparisons and geographical distribution.


Assuntos
Bromeliaceae , Ecossistema , Brasil , Florestas , Plantas
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