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1.
AoB Plants ; 16(4): plae037, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38993261

RESUMO

n the Neotropics, the focus of apomictic studies predominantly centres on trees within the Brazilian savanna, characterized, mostly as sporophytic and facultative, associated with polyploidy and polyembryony. To enhance our understanding of the mechanisms governing apomixis and sexual reproduction in tropical herbaceous plants, we clarify the relationship between apomixis, chromosome counts, and polyembryony in the epiphytic orchid Zygopetalum mackayi, which forms a polyploid complex within rocky outcrops in both the Brazilian savanna and the Atlantic forest. To define embryo origins and describe megasporogenesis and megagametogenesis, we performed manual self-pollinations in first-day flowers of cultivated plants, considering all three cytotypes (2x, 3x, 4x) of this species. Flowers and fruits at different stages were collected to describe the development and morphology of ovules and seeds considering sexual and apomictic processes. As self-pollination treatments resulted in high fruit abortion in diploids, we also examined pollen tube development in aborted flowers and fruits to search for putative anomalies. Megasporogenesis and megagametogenesis occur regularly in all cytotypes. Apomixis is facultative and sporophytic, and associated with polyploid cytotypes, while diploid individuals exclusively engage in sexual reproduction. Polyembryony is caused mainly by the production of adventitious embryos from nucellar cells of triploids and tetraploids, but also by the development of multiple archesporia in all cytotypes. Like other apomictic angiosperms within the Brazilian savanna, our findings demonstrate that apomixis in Z. mackayi relies on pollinators for seed production. We also consider the ecological implications of these apomictic patterns in Z. mackayi within the context of habitat loss and its dependence on pollinators.

2.
Plants (Basel) ; 13(13)2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38999672

RESUMO

The baru (Dipteryx alata Vog.), a fruit native to the Cerrado biome, is well-known for its almonds, which are extensively exploited and exported. Unfortunately, the remaining parts of this fruit are often discarded. This study investigates the fixed chemical constituents of the baru, including the bark, pulp, endocarp, and almonds, using the PS-MS technique in positive and negative ionization modes. Notably, this research presents the first chemical profile of baru almonds in both their raw and roasted states. The analysis identified 57 compounds reported for the first time in a baru and 24 common compounds. The majority of these compounds are classified as flavonoids. In both ionization modes, the peel exhibited a higher proportion of phenolic compounds, although the chemical compounds varied among the peel, pulp, almond, and endocarp. These findings highlight the perspective of bioeconomy and biotechnology. By staggering baru fruit production alongside extractivists, we can optimize the utilization of all parts of the fruit. Furthermore, given the knowledge of the biological properties of flavonoids and the baru composition, we recommend additional studies to analyze their potential in preventing chronic non-communicable diseases.

3.
J Environ Manage ; 365: 121576, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38955045

RESUMO

Savannas and grasslands have lost almost 50% of their original cover worldwide. Therefore, the development of methods and information on open-canopy ecosystem restoration is urgent for the inclusion of these ecosystems into global and regional priorities. In the Brazilian savanna, the most diverse savanna in the world, restoration efforts focused on open ecosystems have been virtually absent, but have increased in the last 10 years. Such efforts are frequently threatened by invasive exotic grasses (IEG) that invade and dominate areas excluding native species, oftentimes aided by altered soil conditions. Long-term studies of savanna restoration trajectories are rare. In this study, we surveyed 22 savanna restoration areas established two to ten years before the study with similar restoration methods to assess their current status. We show that the current restoration methods are successful in establishing native species and allowing species turnover but they are threatened by IEG. Restoration success varies and is affected by soil conditions, IEG landscape cover and post-sowing weeding. Despite that, the simultaneous introduction of different plant functional groups allows turnover from fast to slow-growing plants. Establishing savanna native species is possible at an operational scale with current knowledge and techniques. However, native species establishment fails to prevent IEG reinfestation, which needs to be managed in restoration efforts in the Brazilian savanna.


Assuntos
Conservação dos Recursos Naturais , Pradaria , Brasil , Poaceae/crescimento & desenvolvimento , Ecossistema , Espécies Introduzidas
4.
Sci Rep ; 14(1): 15456, 2024 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-38965317

RESUMO

Medicinal plant microbiomes undergo selection due to secondary metabolite presence. Resident endophytic/epiphytic microorganisms directly influence plant's bioactive compound synthesis. Hypothesizing low microbial diversity in Serjania erecta leaves, we assessed leaf colonization by epiphytic and endophytic fungi. Given its traditional medicinal importance, we estimated diversity in the endophytic fungal microbiome. Analyses included scanning electron microscopy (SEM), isolation of cultivable species, and metagenomics. Epiphytic fungi interacted with S. erecta leaf tissues, horizontally transmitted via stomata/trichome bases, expressing traits for nematode trapping. Cultivable endophytic fungi, known for phytopathogenic habits, didn't induce dysbiosis symptoms. This study confirms low leaf microbiome diversity in S. erecta, with a tendency towards more fungal species, likely due to antibacterial secondary metabolite selection. The classification of Halicephalobus sp. sequence corroborated the presence of nematode eggs on the epidermal surface of S. erecta by SEM. In addition, we confirmed the presence of methanogenic archaea and a considerable number of methanotrophs of the genus Methylobacterium. The metagenomic study of endophytic fungi highlighted plant growth-promoting yeasts, mainly Malassezia, Leucosporidium, Meyerozyma, and Hannaella. Studying endophytic fungi and S. erecta microbiomes can elucidate their impact on beneficial bioactive compound production, on the other hand, it is possible that the bioactive compounds produced by this plant can recruit specific microorganisms, impacting the biological system.


Assuntos
Fungos , Microbiota , Nematoides , Folhas de Planta , Folhas de Planta/microbiologia , Folhas de Planta/parasitologia , Animais , Nematoides/microbiologia , Fungos/classificação , Fungos/genética , Fungos/isolamento & purificação , Endófitos/genética , Endófitos/isolamento & purificação , Leveduras/classificação , Leveduras/isolamento & purificação , Leveduras/genética , Metagenômica/métodos , Biodiversidade
5.
Food Res Int ; 191: 114687, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39059945

RESUMO

Considered the symbol fruit of the Brazilian Cerrado, pequi (Caryocar brasiliense Camb.) is an exotic and much-appreciated fruit with an internal mesocarp (edible part) with an eye-catching golden yellow color. In an unprecedented way, this study characterized the proteome throughout pequi development. The most influential and essential transcription factors operating in the regulation of pequi ripening identified were members of the MAD-box family. A group of proteins related to the methionine cycle indicates the high consumption and recycling of methionine. However this consumption does not occur mainly for the biosynthesis of ethylene, a process dependent on methionine consumption. In the bioactive compounds presented, different proteins could be correlated with the presence of these phytochemicals, such as monodehydroascorbate reductase and ascorbate peroxidase in ascorbic acid recycling; pyruvate kinase, fructose bisphosphate aldolase and phytoene synthase with carotenoid biosynthesis; S-adenosylmethionine synthase 1 as a donor of methyl groups in the formation of trigonelline and aspartate aminotransferase as a biomarker of initial regulation of the trigonelline biosynthetic pathway; phenylalanine ammonia lyase, chorismate synthesis and chalcone-flavononone isomerase in the biosynthesis of phenolic compounds. Among the volatile organic compounds identified, the majority compound in pequi was ethyl hexanoate ester, with an area of 50.68 % in the ripe fruit, and in this group of esters that was the most representative, alcohol dehydrogenase, a fundamental enzyme in the synthesis of esters, was identified with an increase of approximately 7.2 times between the first and last stages. Therefore, an extensive group of proteins and some metabolites can serve as biomarkers of ripening in pequi, as most were more expressed in the last stage, which is the ripe fruit suitable for consumption.


Assuntos
Frutas , Metaboloma , Proteínas de Plantas , Proteoma , Frutas/crescimento & desenvolvimento , Frutas/metabolismo , Proteoma/metabolismo , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas
6.
Food Res Int ; 188: 114500, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38823879

RESUMO

Located in Brazil's Central Plateau, the Cerrado Savannah is an emerging coffee-growing region with significant potential for the national coffee market. This study investigated the impact of potassium fertilization on Arabica coffee quality in the Cerrado, using three potassium sources (K2SO4, KCl, and KNO3) and five cultivars (Arara, Aranãs, IPR103, Catiguá and Topázio) across two consecutive harvests. We focused on productivity, granulometry, chemical composition, and sensory characteristics. No significant difference in productivity across the cultivars studied or potassium sources as isolated factors were observed. Regarding chemical parameters, potassium sources only affected NO3- and SO42- levels in the grains. Cultivar-specific differences were noted in caffeine (CAF), citric acid (CA), and sucrose (SUC), highlighting a strong genetic influence. K2SO4 improved productivity in Arara (15 %) and IPR103 (11 %), while KNO3 reduced flat grain percentage to 70 % in Catiguá. Sensory evaluation showed that all potassium sources and cultivars produced specialty coffees, with the Arara cultivar treated with K2SO4 achieving the highest SCA score (83.3) while IPR 103 treated with KCl scored the lowest at 78. Only three treatments were below but very close to the threshold (80). Multivariate analysis indicated a trend where specific treatments correlated with higher productivity and quality. Despite the subtle differences in productivity and quality among potassium sources, a cost-benefit analysis may favor KCl due to its affordability, suggesting its viability as a potassium fertilization option in coffee cultivation. Future research is needed to confirm these trends and optimize potassium source selection to enhance coffee quality in the Cerrado.


Assuntos
Coffea , Potássio , Brasil , Coffea/química , Coffea/crescimento & desenvolvimento , Potássio/análise , Sementes/química , Sementes/crescimento & desenvolvimento , Café/química , Paladar , Fertilizantes , Humanos , Cafeína/análise
7.
Mol Ecol ; 33(14): e17431, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38877815

RESUMO

The South American Dry Diagonal, also called the Diagonal of Open Formations, is a large region of seasonally dry vegetation extending from northeastern Brazil to northern Argentina, comprising the Caatinga, Cerrado, and Chaco subregions. A growing body of phylogeography literature has determined that a complex history of climatic changes coupled with more ancient geological events has produced a diverse and endemic-rich Dry Diagonal biota. However, the exact drivers are still under investigation, and their relative strengths and effects are controversial. Pleistocene climatic fluctuations structured lineages via vegetation shifts, refugium formation, and corridors between the Amazon and Atlantic forests. In some taxa, older geological events, such as the reconfiguration of the São Francisco River, uplift of the Central Brazilian Plateau, or the Miocene inundation of the Chaco by marine incursions, were more important. Here, we review the Dry Diagonal phylogeography literature, discussing each hypothesized driver of diversification and assessing degree of support. Few studies statistically test these hypotheses, with most support drawn from associating encountered phylogeographic patterns such as population structure with the timing of ancient geoclimatic events. Across statistical studies, most hypotheses are well supported, with the exception of the Pleistocene Arc Hypothesis. However, taxonomic and regional biases persist, such as a proportional overabundance of herpetofauna studies, and the under-representation of Chaco studies. Overall, both Pleistocene climate change and Neogene geological events shaped the evolution of the Dry Diagonal biota, though the precise effects are regionally and taxonomically varied. We encourage further use of model-based analyses to test evolutionary scenarios, as well as interdisciplinary collaborations to progress the field beyond its current focus on the traditional set of geoclimatic hypotheses.


Assuntos
Filogeografia , Mudança Climática , América do Sul , Biodiversidade , Clima Tropical
8.
Int J Biol Macromol ; 275(Pt 1): 133208, 2024 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-38889837

RESUMO

Jatobá-do-cerrado fruit shells, archetypical of lignocellulosic-based biomass, were used as an adsorbent to remove crystal violet (CV) and methylene blue (MB) from water. The adsorbent was characterized using various techniques, and kinetic studies showed dye adsorption followed second-order kinetics. An experimental design investigated the effects of pH and temperature on removal efficiency, with a quadratic model fitting the data best. The results suggest pH influences MB's adsorption capacity more than temperature and at 25 °C and pH 8, MB had a desirability value of 0.89, with 95 % removal efficiency. For CV, temperature had a greater influence, with a desirability value of 0.874 at 25 °C and pH 10, and 95 % removal efficiency. Adsorption isotherm studies revealed maximum adsorption capacities of 123.0 mg·g-1 and 113.0 mg·g-1 for CV and MB, respectively. Experimental thermodynamic parameters indicated an endothermic and spontaneous process which it was supported by quantum chemistry calculations. The protocols developed confirmed the potential for adsorbing CV and MB dyes in water, achieving over 73.1 and 74.4 mg g-1 dyes removal.

9.
Plant Biol (Stuttg) ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38940062

RESUMO

In fire-prone ecosystems, plant traits are influenced by the fire regime, thus reproduction and establishment can be altered by this disturbance. Changes in fire frequency and history can therefore influence seed and germination traits. We investigated the effects of short-term fire exclusion on seed and germination traits of species from tropical open savannas. Seeds from 27 species were collected from two areas with distinct fire histories: recently and frequently burned (RB) or unburned for 5 to 7 years (E). Seeds from both areas underwent germination trials under optimal conditions for 30 days. Also, 10 species were exposed to high temperature treatments (100 or 200 °C) and seed and germination traits measured. Comparisons were then made for each trait, analysing each species separately, between the two areas. Approximately 85% of species studied had at least one of their germination traits altered in the RB area compared to the E area. Clear differences included lower viability and faster germination in seeds from RB areas. Seed traits of 70% of measured species differed between the two areas. Our results show species-specific trait response to different fire histories. For example, faster germination and lower viability of seeds from RB plots suggest selection for faster maturing individuals and differences in resourcing, respectively, under a regime of frequent fire. This study provides insights into fire effects on regeneration responses of tropical savanna species and also points to the need for more studies evaluating the effects of fire history on seed traits.

10.
Ecology ; 105(8): e4365, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38895926

RESUMO

Scavenging is a key process for the cycling of nutrients in ecosystems, yet it is still neglected in the ecological literature. Apart from the importance of specific groups of animals in scavenging, there have been few ecological studies that compare them. Furthermore, the ecological studies on scavenging have mainly focused on vertebrates despite the crucial importance of invertebrates in this process. Here, we performed a large-scale ant suppression and vertebrate exclusion experiment to quantify the relative contribution of ants, non-ant invertebrates and vertebrates in scavenging nitrogen-rich (insect carcasses) and carbon-rich (seeds) baits in two contrasting mountainous habitats in Brazil (grasslands and forests). Overall, bait removal was 23.2% higher in forests than in grasslands. Ants were the primary scavengers in grasslands, responsible for more than 57% of dead insect larvae and seed removal, while, in forests, non-ant invertebrates dominated, removing nearly 65% of all baits. Vertebrates had a minor role in scavenging dead insect larvae and seeds in both habitats, with <4% of removals. Furthermore, our results show that animal-based baits were more consumed in forests than seeds, and both resources were equally consumed in grasslands. Therefore, we demonstrate the superiority of invertebrates in this process, with a particular emphasis on the irreplaceable role of ants, especially in this grassland ecosystem. As such, we further advance our knowledge of a key ecosystem process, showing the relative importance of three major groups in scavenging and the differences in ecosystems functioning between two contrasting tropical habitats.


Assuntos
Formigas , Florestas , Pradaria , Invertebrados , Animais , Formigas/fisiologia , Invertebrados/fisiologia , Brasil , Comportamento Alimentar/fisiologia , Ecossistema , Insetos/fisiologia
11.
J Med Food ; 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38695868

RESUMO

Given the importance of discovering plant species from the Brazilian Cerrado biome with anticancer potential, this study evaluated the antitumor activity of two extracts of Campomanesi adamantium fruits in in vitro and in vivo models of melanoma lung metastasis. Pulp and peel extracts (DEGPU and DEGPE, respectively) were extracted from fresh fruit using dichloromethane as a solvent. As cytotoxicity parameter, concentration values that inhibited 50% cell growth (GI50), total growth inhibition (TGI), and selectivity index (SI) were established. The melanoma lung metastasis model was obtained by injecting 5 × 105/50 µL B16-F10 cells via the tail vein of mice, which received treatment on the 15th day. Metastatic lungs were collected for fluorescence analysis with the IR-780 marker and also macro- and microscopic assessment. In vitro analyses showed that DEGPU was active in K562 (GI50 32.99; TGI 47.93) and U-251 (GI50 32.10; TGI 249.92), whereas DEGPE showed better cytotoxicity results for all tumor cell lines, but was more efficient in K562 (GI50 27.42; TGI 40.20) and U-251 (GI50 4.89; TGI 12.77). Both showed a cytocidal effect on B16F10 at the highest concentration tested, with approximately 25% (DEGPU) and 88% (DEGPE) of cell death. In vivo analyzes showed that both extracts showed significant activity in metastatic lung. Fluorescence images showed differences in intensity between groups owing to greater tumor involvement. Macro- and microscopic images showed that treatments with extracts limited tumor growth and prevented proliferation. The extracts tested have promising activity, thus requiring further research on their active compounds.

12.
Sci Total Environ ; 931: 172958, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38714255

RESUMO

Mining activities put the Brazilian savannas, a global biodiversity hotspot, in danger of species and soil carbon losses. Experiments employing biosolids have been applied to rejuvenate this degraded ecosystem, but a lingering question yet to be answered is whether the microbiota that inhabits these impoverished soils can be recovered towards its initial steady state after vegetation recovery. Here, we selected an 18-year-old restoration chronosequence of biosolids-treated, untreated mining and native soils to investigate the soil microbiota recovery based on composition, phylogeny, and diversity, as well as the potential factors responsible for ecosystem recovery. Our results revealed that the soil microbiota holds a considerable recovery potential in the degraded Cerrado biome. Biosolids application not only improved soil health, but also led to 41.7 % recovery of the whole microbial community, featuring significantly higher microbiota diversity and enriched groups (e.g., Firmicutes) that benefit carbon storage compared to untreated mining and native soils. The recovered community showed significant compositional distinctions from the untreated mining or native soils, rather than phylogenetic differences, with physiochemical properties explaining 55 % of the overall community changes. This study advances our understanding of soil microbiota dynamics in response to disturbance and restoration by shedding light on its recovery associated with biosolid application in a degraded biodiverse ecosystem.


Assuntos
Microbiota , Microbiologia do Solo , Solo , Brasil , Solo/química , Mineração , Biodiversidade , Ecossistema , Recuperação e Remediação Ambiental/métodos
13.
Environ Res ; 252(Pt 2): 118906, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38609069

RESUMO

Litterfall is the main source of dry deposition of mercury (Hg) into the soil in forest ecosystems. The accumulation of Hg in soil and litter suggests the possibility of transfer to terrestrial invertebrates through environmental exposure or ingestion of plant tissues. We quantified total mercury (THg) concentrations in two soil layers (organic: 0-0.2 m; mineral: 0.8-1 m), litter, fresh leaves, and terrestrial invertebrates of the Araguaia River floodplain, aiming to evaluate the THg distribution among terrestrial compartments, bioaccumulation in invertebrates, and the factors influencing THg concentrations in soil and invertebrates. The mean THg concentrations were significantly different between the compartments evaluated, being higher in organic soil compared to mineral soil, and higher in litter compared to mineral soil and fresh leaves. Soil organic matter content was positively related to THg concentration in this compartment. The order Araneae showed significantly higher Hg concentrations among the most abundant invertebrate taxa. The higher Hg concentrations in Araneae were positively influenced by the concentrations determined in litter and individuals of the order Hymenoptera, confirming the process of biomagnification in the terrestrial trophic chain. In contrast, the THg concentrations in Coleoptera, Orthoptera and Hymenoptera were not significantly related to the concentrations determined in the soil, litter and fresh leaves. Our results showed the importance of organic matter for the immobilization of THg in the soil and indicated the process of biomagnification in the terrestrial food web, providing insights for future studies on the environmental distribution of Hg in floodplains.


Assuntos
Bioacumulação , Monitoramento Ambiental , Invertebrados , Mercúrio , Rios , Mercúrio/análise , Mercúrio/metabolismo , Brasil , Animais , Rios/química , Invertebrados/metabolismo , Poluentes do Solo/análise , Poluentes do Solo/metabolismo , Pradaria , Cadeia Alimentar , Ecossistema , Solo/química
14.
Braz J Microbiol ; 55(2): 1099-1115, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38605254

RESUMO

An Actinobacteria - Kitasatospora sp. K002 - was isolated from the soil of Cerrado, a savanna-like Brazilian biome. Herein, we conducted a phylogenetic, phenotypic and physiological characterization, revealing its potential for biotechnological applications. Kitasatospora sp. K002 is an aerobic, non-motile, Gram-positive bacteria that forms grayish-white mycelium on solid cultures and submerged spores with vegetative mycelia on liquid cultures. The strain showed antibacterial activity against Bacillus subtilis, Pseudomonas aeruginosa and Escherichia coli. Genomic analysis indicated that Kitasatospora xanthocidica JCM 4862 is the closest strain to K002, with a dDDH of 32.8-37.8% and an ANI of 86.86% and the pangenome investigations identified a high number of rare genes. A total of 60 gene clusters of 22 different types were detected by AntiSMASH, and 22 gene clusters showed low similarity (< 10%) with known compounds, which suggests the potential production of novel bioactive compounds. In addition, phylogenetic analysis and morphophysiological characterization clearly distinguished Kitasatospora sp. K002 from other related species. Therefore, we propose that Kitasatospora sp. K002 should be recognized as a new species of the genus Kitasatospora - Kitasatospora brasiliensis sp. nov. (type strains = K002).


Assuntos
Genoma Bacteriano , Filogenia , Microbiologia do Solo , Brasil , Actinobacteria/genética , Actinobacteria/classificação , Actinobacteria/isolamento & purificação , Actinobacteria/fisiologia , Antibacterianos/farmacologia , RNA Ribossômico 16S/genética , DNA Bacteriano/genética , Biotecnologia , Genômica , Técnicas de Tipagem Bacteriana
15.
Food Res Int ; 184: 114241, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38609221

RESUMO

This review aimed to critically and comparatively analyze the physicochemical, proximate, nutritional, phytochemical composition, and bioactivities of araticum (Annona crassiflora Mart.) (AAc), a fruit from the Brazilian Cerrado. Additionally, the potential applications of this fruit in the food industry were reviewed. Data and information were collected from the Scopus, Web of Science, and Google Scholar databases. AAc, a fruit mainly studied in the Brazilian regions of Minas Gerais and Goiás, has well-documented physicochemical, proximate, and nutritional characteristics. It is rich in fiber, sugars, vitamins A and C, minerals, and oil, making it attractive to the food industry. However, there are research gaps, such as the impact of climatic conditions on the AAc chemical composition. Additional studies are needed, especially for the peel and seeds, and investigations of pre-treatments effect on the chemical composition are recommended. The application of AAc in food products is mainly limited to pulp, but there is potential for using peels and seeds. AAc is a rich source of phytochemical compounds with various biological properties, such as antioxidants, hepatoprotective, and antimicrobial activities. Future studies should explore other phytochemicals present in the fruit beyond phenolic compounds. The consumption of AAc can contribute to combating food insecurity malnutrition, and promoting the conservation of the Brazilian Cerrado.


Assuntos
Annona , Indústria Alimentícia , Frutas , Sementes , Compostos Fitoquímicos
16.
Ecol Evol ; 14(3): e11094, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38476698

RESUMO

Pollination is vital for ecosystem functioning, especially in biodiversity-rich regions like the Brazilian Cerrado. Our research establishes a comprehensive meta network of pollinator-plant interactions within this biome. We quantified the importance of different pollinator groups, identifying keystone species. We examined potential biases in sampling effort and the spatial behavior of interactions within the heterogeneous Cerrado plant physiognomies. Our investigation uncovered 1499 interactions among 293 plant species and 386 visitor species, with legitimate pollination accounting for 42.4% of the interactions. The network exhibited modularity, driven by bees and insects, with vertebrates bridging diurnal and nocturnal modules. While a generalized pattern emerged, high specialization existed within modules due to habitat diversity. Bees, particularly Apis mellifera (exotic) and Trigona spinipes (native), played central roles as network hubs. Hummingbirds and bats, engaged in specialized interactions showing strong connectivity within and between modules. Interestingly, invertebrate-vertebrate modules were more prevalent than expected in the meta network. However, a bias was evident, primarily within specific biogeographical districts with fragmented landscapes and intrusion from other biomes. Variations in plant species and endemism rates influenced pollinator occurrence and the Cerrado network topology. Our study offers valuable insights into pollinator-plant interactions within the Cerrado, encompassing both invertebrates and vertebrates. The modeled network represents a significant step in understanding the structural complexity of pollination networks, integrating partial networks from diverse pollination systems within heterogeneous habitats. Nevertheless, a biogeographical bias could limit a comprehensive understanding of network functionality across the Cerrado.

17.
Plants (Basel) ; 13(5)2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38475497

RESUMO

The net outcomes of mutualisms are mediated by the trade-offs between the costs and benefits provided by both partners. Our review proposes the existence of a trade-off in ant protection mutualisms between the benefits generated by the ants' protection against the attack of herbivores and the losses caused by the disruption of pollination processes, which are commonly not quantified. This trade-off has important implications for understanding the evolution of extrafloral nectaries (EFNs), an adaptation that has repeatedly evolved throughout the flowering plant clade. We propose that the outcome of this trade-off is contingent on the specific traits of the organisms involved. We provide evidence that the protective mutualisms between ants and plants mediated by EFNs have optimal protective ant partners, represented by the optimum point of the balance between positive effects on plant protection and negative effects on pollination process. Our review also provides important details about a potential synergism of EFN functionality; that is, these structures can attract ants to protect against herbivores and/or distract them from flowers so as not to disrupt pollination processes. Finally, we argue that generalizations regarding how ants impact plants should be made with caution since ants' effects on plants vary with the identity of the ant species in their overall net outcome.

18.
Rev. argent. cir ; 116(1): 50-55, mar. 2024. tab
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1559265

RESUMO

RESUMEN Antecedentes: el tratamiento conservador no invasivo del traumatismo esplénico disminuye intervenciones quirúrgicas innecesarias y depende centro asistencial donde es aplicado. Objetivo: describir los resultados del tratamiento conservador no invasivo de pacientes con traumatismo abdominal cerrado con lesión esplénica y correlacionarlos con variables preoperatorias. Material y métodos: trabajo observacional descriptivo de pacientes con traumatismo abdominal cerrado con lesión esplénica ingresados entre 2012-2022. Se analizaron cinemática del traumatismo, lesiones asociadas, grado de lesión tomográfica y de hemoperitoneo, lugar de internación y resultado del tratamiento conservador no invasivo. Resultados: en 102 pacientes la cinemática del traumatismo de mayor frecuencia fue moto/auto (47,1%); el porcentaje de éxito del tratamiento conservador no invasivo fue 66,6%, y se relacionó con el grado de lesión tomográfica (p <0,001), grado de hemoperitoneo (p <0,001), presencia de otras lesiones (p <0,001), traumatismo encéfalo craneano grave (p <0,009), y lugar de internación (p <0,002). Conclusión: a pesar de no contar con todos los recursos humanos y tecnológicos recomendados, el tratamiento conservador no invasivo en esta serie tuvo resultados comparables con centros de mayor complejidad.


ABSTRACT Background: Non-invasive conservative treatment of splenic trauma reduces the rate of unnecessary surgical interventions and depends on the type of healthcare center involved. Objective: The aim of this study is to describe the outcomes of non-invasive conservative treatment in patients with blunt abdominal trauma and splenic injury and their correlation with the preoperative variables. Material and methods: We conducted a retrospective and observational study of patients admitted with blunt abdominal trauma and splenic injury between 2012 and 2022. The variables analyzed were kinematics of trauma, lesion severity on computed tomography images, amount of hemoperitoneum, type of unit of hospitalization and results of non-invasive conservative treatment. Results: Among 102 patients, the most common kinematics of trauma was motorcycle-to-car collisions (47.1%); the success rate of non-invasive conservative treatment was 66.6%, and was associated with lesion severity on computed tomography images (p < 0.001), amount of hemoperitoneum (p < 0.001), presence of other injuries (p < 0.001), severe trauma brain injury (p < 0.009), and type of unit of hospitalization (p < 0.002). Conclusion: Despite the absence of recommended human and technological resources, the results of non-invasive conservative treatment in this series were comparable to those obtained in high complexity centers.

19.
Mol Phylogenet Evol ; 194: 108031, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38360081

RESUMO

Our knowledge of the systematics of the papilionoid legume tribe Brongniartieae has greatly benefitted from recent advances in molecular phylogenetics. The tribe was initially described to include species marked by a strongly bilabiate calyx and an embryo with a straight radicle, but recent research has placed taxa from the distantly related core Sophoreae and Millettieae within it. Despite these advances, the most species-rich genera within the Brongniartieae are still not well studied, and their morphological and biogeographical evolution remains poorly understood. Comprising 35 species, Harpalyce is one of these poorly studied genera. In this study, we present a comprehensive, multi-locus molecular phylogeny of the Brongniartieae, with an increased sampling of Harpalyce, to investigate morphological and biogeographical evolution within the group. Our results confirm the monophyly of Harpalyce and indicate that peltate glandular trichomes and a strongly bilabiate calyx with a carinal lip and three fused lobes are synapomorphies for the genus, which is internally divided into three distinct ecologically and geographically divergent lineages, corresponding to the previously recognized sections. Our biogeographical reconstructions demonstrate that Brongniartieae originated in South America during the Eocene, with subsequent pulses of diversification in South America, Mesoamerica, and Australia. Harpalyce also originated in South America during the Miocene at around 20 Ma, with almost synchronous later diversification in South America and Mexico/Mesoamerica beginning 10 Ma, but mostly during the Pliocene. Migration of Harpalyce from South to North America was accompanied by a biome and ecological shift from savanna to seasonally dry forest.


Assuntos
Fabaceae , Filogenia , Fabaceae/genética , Pradaria , Florestas , Ecossistema , Teorema de Bayes , Filogeografia
20.
J Plant Res ; 137(3): 377-393, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38369599

RESUMO

The tree genus Dimorphandra (Fabaceae), which contains 26 species divided into three subgenera, was studied using DNA sequence data from six chloroplast genome regions (cpDNA) and the nuclear internal transcribed spacer (ITS). The analyses, which included Bayesian phylogenies and haplotype networks, ancestral area reconstructions, and ecological niche modeling, allowed for exploring the evolutionary history of Dimorphandra. Within the subgenus Phaneropsia, the cpDNA sequence data were more closely-related to species from the genus Mora, while the ITS sequence data displayed a closer phylogenetic relationship with the subgenus Pocillum. This incongruence may be due to incomplete lineage sorting associated with ancient polymorphisms. The Amazonian Dimophandra lineages were highly polymorphic and divergent, while those from the Cerrado and the Atlantic Forest had low levels of polymorphisms. The Amazon likely gave rise to the Dimophandra lineage that produced the Cerrado species, while a Cerrado lineage likely gave rise to the Atlantic Forest species. Habitat shifts were identified as a key factor in shaping the late evolutionary history of Dimorphandra.


Assuntos
Fabaceae , Florestas , Pradaria , Filogenia , Fabaceae/genética , Fabaceae/classificação , DNA de Cloroplastos/genética , Haplótipos , Evolução Biológica , Análise de Sequência de DNA , Genoma de Cloroplastos/genética , Teorema de Bayes , Evolução Molecular , DNA de Plantas/genética , Ecossistema
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