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1.
Plants (Basel) ; 13(19)2024 Oct 03.
Article in English | MEDLINE | ID: mdl-39409639

ABSTRACT

The Cerrado has high plant and vertebrate diversity and is an important biome for conserving species and provisioning ecosystem services. Volume equations in this biome are scarce because of their size and physiognomic diversity. This study was conducted to develop specific volumetric models for the phytophysiognomies Gallery Forest, Dry Forest, Forest Savannah, and Savannah Woodland, a generic model and a model for Cerrado forest formation. Twelve 10 m × 10 m (100 m²) (National Forest Inventory) plots were used for each phytophysiognomy at different sites (regions) of the Federal District (FD) where trees had a diameter at breast height (DBH; 1.30 m) ≥5 cm in forest formations and a diameter at base height (Db; 0.30 m) ≥5 cm in savanna formations. Their diameters and heights were measured, they were cut and cubed, and the volume of each tree was obtained according to the Smalian methodology. Linear and nonlinear models were adjusted. Criteria for the selection of models were determined using correlation coefficients, the standard error of the estimates, and a graphical analysis of the residues. They were later validated by the chi-square test. The resultant models indicated that fit by specific phytophysiognomy was ideal; however, the generic and forest formation models exhibited similar performance to specific models and could be used in extensive areas of the Cerrado, where they represent a high potential for generalization. To further increase our understanding, similar research is recommended for the development of specific and generic models of the total volume in Cerrado areas.

2.
Plants (Basel) ; 13(19)2024 Oct 09.
Article in English | MEDLINE | ID: mdl-39409696

ABSTRACT

Research related to Cerradão vegetation focuses more on the floristic-structural aspect, with rare studies on the quantification of volume and biomass stocks, and even fewer investigating the increments of these attributes. Using a systematic sampling method with subdivided strips and 400 m2 plots, the density found was 1135, 1165, and 1229 trees/ha in 2012, 2020, and 2023, respectively, in Lajeado State Park, Tocantins State, Brazil. Volume was estimated using the equation v=0.000085D2.122270H0.666217, and biomass was estimated using the equation AGB=0.0673ρD2H0.976. Vegetation dynamics were assessed using growth increment, recruitment, mortality, turnover rate, and time. The results indicated that dynamics have increased since the start of monitoring. Typical Cerrado species, in the strict sense, were replaced by those from forest environments. The total production in volume and biomass was 160.91 m3/ha and 118.10 Mg/ha, respectively, in 2023. The species of Emmotum nitens, Mezilaurus itauba, Ocotea canaliculata, and Sacoglottis guianensis showed the highest increment values in volume and biomass. For the community, the average values were 4.04 m3/ha/year and 3.54 Mg/ha/year. The community has not yet reached its carrying capacity and stores a significant amount of biomass. This is influenced by the transition of the study area from an exploited environment to a conservation unit (park) and by its location in a transitional area with the Amazon biome.

3.
Plant Biol (Stuttg) ; 2024 Oct 16.
Article in English | MEDLINE | ID: mdl-39412517

ABSTRACT

Post-fire regeneration characterizes woody vegetation of the Cerrado. Several species (e.g., from the Fabaceae) can resprout after fire due to the presence of storage bud-bearing belowground structures, such as xylopodia, having the capacity to rapidly allocate resources for the formation of new aboveground shoots, an advantage in fire-prone ecosystems. Therefore, we evaluated the morphoanatomical structure of the belowground organs, buds and their storage to elucidate fire-related functional traits in relation to regeneration. Besides the strong capacity of plants with xylopodia to resprout and/or their associated root suckers to propagate laterally, they also provide protection against pathogens, through the presence of defence compounds. We evaluated the morphoanatomy and performed histochemical tests with the belowground organs of eight legume species collected in open savannas in Central Brazil. Two species presented a taproot tuber and the six remaining species had a xylopodium as belowground organ. All xylopodia had buds on their upper portion. These organs were basically composed of lignified tissue, containing defence (phenolic compounds and lipidic substances), and storage (starch) substances. All xylopodia were associated to tuberous roots, and in two species these roots were also root suckers. Thus, the presence of belowground storage organs, in combination with stored defence compounds, likely facilitates the persistence of the investigated legumes in fire-prone ecosystems.

4.
Environ Sci Pollut Res Int ; 31(51): 61254-61269, 2024 Nov.
Article in English | MEDLINE | ID: mdl-39412717

ABSTRACT

The unregulated use and improper management of herbicides can cause negative effects on non-target species and promote changes in biological communities. Therefore, the current study is aimed at understanding morphoanatomical responses and effects on seedling development induced by the herbicides glyphosate and saflufenacil in Enterolobium contortisiliquum, a non-target tropical species. The plants were cultivated in a greenhouse and subjected to herbicides at doses of 0, 160, 480, and 1440 g a.e ha-1 for glyphosate, and 0, 25, 50, and 100 g a.i ha-1 for saflufenacil. We conducted visual and morphological assessments over 90 days post-application. Leaf samples were collected 12 days after the application for anatomical analysis, and we also performed a micromorphometric analysis of the leaf tissues. Biomarkers of phytotoxicity were identified in plants exposed to both herbicides, even at the lowest doses, including in leaves without visual symptoms. The main morphological alterations were the decrease in growth, stem diameter, and dry mass. Furthermore, the leaves and stems visually exhibited chlorosis and necrosis. Both herbicides triggered anatomical modifications such as significant changes (p < 0.05) in the thickness of leaf tissues, hypertrophy, cell collapse, and changes in epicuticular waxes. However, the alterations induced by glyphosate were more widespread compared to saflufenacil, encompassing alterations in the root system. We confirmed that the different mechanisms of action of each herbicide and the existence of an underground reserve system in this species are intrinsically linked to the morphological and developmental responses described. Our findings suggest that E. contortisiliquum could be a potential bioindicator species for these herbicides in the environment, even at concentrations lower than those typically recommended for field application.


Subject(s)
Fabaceae , Glycine , Glyphosate , Herbicides , Herbicides/toxicity , Glycine/analogs & derivatives , Glycine/toxicity , Fabaceae/drug effects , Trees/drug effects , Plant Leaves/drug effects , Seedlings/drug effects , Seedlings/growth & development , Pyrimidinones , Sulfonamides
5.
Braz J Infect Dis ; 28(5): 103874, 2024.
Article in English | MEDLINE | ID: mdl-39332813

ABSTRACT

Leprosy is a chronic infectious disease caused by the bacilli Mycobacterium leprae and Mycobacterium lepromatosis. In addition to humans, animals such as nine-banded armadillos and red squirrels are species naturally infected. The objective of this study was to investigate the presence of M. leprae and M. lepromatosis in non-volant small mammals of the order Didelphimorphia and Rodentia through Polymerase Chain Reaction (PCR) assay. During 2015 and 2018, field expeditions were carried out in three municipalities, covering biotic elements of the Amazon and Cerrado biomes, in the Mato Grosso State, Midwest of Brazil. A specific primer for repetitive sequences of the genomic DNA of M. leprae and M. lepromatosis targeting the RLEP and RLPM gene, respectively, was used to screen for these agents. The molecular detection of M. leprae DNA in the samples was 13.8%. M. lepromatosis was not detected. The present study reports a description of M. leprae in small non-volant mammals in Brazil.


Subject(s)
Mycobacterium leprae , Polymerase Chain Reaction , Animals , Brazil/epidemiology , Mycobacterium leprae/genetics , Mycobacterium leprae/isolation & purification , DNA, Bacterial/genetics , Rodentia/microbiology , Leprosy/microbiology , Mycobacterium/genetics , Mycobacterium/isolation & purification , Mycobacterium/classification , Armadillos/microbiology , Leprosy, Lepromatous/microbiology
6.
Neotrop Entomol ; 53(5): 1119-1136, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39259443

ABSTRACT

We provide updated diagnoses for the senex-, burtoni- and dimorphus-groups of Camponotus (Myrmobrachys). Dichotomous keys for the C. (Myrmobrachys) groups and species of the dimorphus-group, based on type-specimens are provided. Two new species of the dimorphus-group are described, Camponotus cameloides sp. nov. and Camponotus hyalus sp. nov. We classified C. dolabratus and C. lancifer as members of the dimorphus-group and C. crassicornis, C. subcircularis, and C. championi as members of the senex-group. Scanning Electron Microscopy was used to describe the branched pilosity of C. cameloides and this is the first description of it for adult workers of Camponotini tribe.


Subject(s)
Ants , Microscopy, Electron, Scanning , Animals , Ants/classification , Ants/anatomy & histology , Female , Male
7.
Plants (Basel) ; 13(18)2024 Sep 12.
Article in English | MEDLINE | ID: mdl-39339535

ABSTRACT

The peel represents a significant portion of the araticum fruit (about 40%), which becomes waste after its consumption or processing. Previous studies have shown that the araticum peel is rich in phenolic compounds; however, little is known about the ideal conditions for recovering these compounds. Therefore, response surface methodology, using a central composite rotatable design, was employed to optimize the extraction process to maximize the total phenolic compounds (TPCs) and enhance the Trolox equivalent antioxidant capacity (TEAC) from araticum peel. The variables optimized were ethanol concentration (EC; 20-80%, v/v), extraction time (ET; 5-45 min), and solid-solvent ratio (SSR; 10-100 mg/mL). Additionally, condensed tannins, antioxidant capacity against synthetic free radicals (TEAC and FRAP) and reactive oxygen species (ROS), and the phenolic compounds profile, were evaluated. Optimum extraction conditions were 50% (v/v) ethanol concentration, 5 min of extraction time, and 10 mg/mL solid-solvent ratio. Under these conditions, experimental TPCs and TEAC values were 70.16 mg GAE/g dw and 667.22 µmol TE/g dw, respectively, comparable with predicted models (68.47 mg GAE/g dw for TPCs and 677.04 µmol TE/g dw for TEAC). A high condensed tannins content (76.49 mg CE/g dw) was also observed and 12 phenolic compounds were identified, predominantly flavonoids (97.77%), including procyanidin B2, epicatechin, and catechin as the major compounds. Moreover, a potent antioxidant activity was observed against synthetic free radicals and ROS, especially in scavenging peroxyl and hydroxyl radicals. From this study, we obtained the ideal conditions for recovering phenolic compounds from araticum peel using a simple, fast, sustainable, and effective method, offering a promising opportunity for the management of this plant byproduct.

8.
Animals (Basel) ; 14(15)2024 Jul 31.
Article in English | MEDLINE | ID: mdl-39123749

ABSTRACT

Wild boars (Sus scrofa L.) are considered among the most harmful invasive species worldwide, causing irreversible ecosystem damage, acting as zoonotic spreaders and reservoirs, threatening human and animal health, and having an important economic impact. Accordingly, the present study has assessed the rickettsial exposure, tick infestation of wild boars, and rickettsial DNA presence in ticks from infested animals from the Cerrado biome in midwestern Brazil. Anti-Rickettsia spp. antibodies were detected in serum samples of wild boars by immunofluorescence assay. Overall, 106/285 (37.2%) wild boar serum samples from 13 to 18 (72.2%) municipalities showed seroreactivity to at least one of the four Rickettsia spp. antigens tested, the largest number of wild boars serologically tested to Rickettsia spp. in this type of study. Among the 106 seroreactive animals, 34 showed possible homologous reactions between R. parkeri, R. amblyommatis, and R. bellii, with endpoint titers between 128 and 512. A sample of 45 ticks collected from four culled wild boars was identified as Amblyomma sculptum, and all tested negative for rickettsial DNA presence. In conclusion, this study has provided a reliable sampling seroprevalence and indicated high exposure of wild boars to rickettsial agents, with a potential interaction with Rickettsia spp. from the spotted fever group within the Cerrado biome from midwestern Brazil.

9.
Plants (Basel) ; 13(15)2024 Jul 23.
Article in English | MEDLINE | ID: mdl-39124134

ABSTRACT

The pequi (Caryocar brasiliense) fruit peel, despite being frequently discarded, has a high content of bioactive compounds, and therefore has a high nutritional value. The present study aimed to explore the bioactivities in the pequi peel, particularly their potential health benefits at the level of antioxidant activity. The exploitation of this fruit could also present significant economic benefits and applications of pequi by-products would represent a reduction in waste, having a positive impact on the environment. Phenolic compounds present in the pequi exocarp and external mesocarp were identified by paper spray mass spectrometry (PS-MS) and quantified by HPLC. The total phenolic content (TPC) along with the amount of 2,2-diphenyl-1-picrylhydrazyl (DPPH), Ferric Reducing Antioxidant Power (FRAP), and the amount of 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS) were also determined in peel extracts. Epicatechin was the most abundant phenolic compound found, followed by the caffeic, salicylic, and gallic acids. In addition, fingerprinting revealed compounds related to several beneficial health effects. In short, the results obtained were encouraging for potential applications of pequi peel in the field of functional foods.

10.
Curr Zool ; 70(4): 453-464, 2024 Aug.
Article in English | MEDLINE | ID: mdl-39176064

ABSTRACT

Knowledge regarding the influence of individual traits on interaction patterns in nature can help understand the topological role of individuals within a network of intrapopulation interactions. We tested hypotheses on the relationships between individuals' positions within networks (specialization and centrality) of 4 populations of the mouse opossum Gracilinanus agilis and their traits (i.e., body length, body condition, tail length relative to body length, sex, reproductive condition, and botfly parasitism) and also seasonal effects in the Brazilian savanna. Individuals with lower body length, better body condition, and relatively shorter tail were more specialized (i.e., less connected within the network). Individuals were also more specialized and less connected during the warm-wet season. The relationship between individuals' position in the network and body traits, however, was independent of season. We propose that specialization may arise not only as a result of preferred feeding strategies by more capable individuals (i.e., those with better body condition and potentially prone to defend and access high-quality food resources) but also because of morphological constraints. Smaller/younger individuals (consequently with less experience in foraging) and short-tailed individuals (less skilled to explore the vertical strata of the vegetation) would feed only on a subset of the available food resources and consequently become more specialized. Moreover, individuals are more specialized during the warm-wet season because of high competition (population-dense period) and higher ecological opportunities (resource-rich period). Therefore, our study reveals the relevance of individual traits in shaping interaction patterns and specialization in populations.

11.
Viruses ; 16(8)2024 Aug 09.
Article in English | MEDLINE | ID: mdl-39205250

ABSTRACT

Studies on animal virome have mainly concentrated on chordates and medically significant invertebrates, often overlooking sylvatic mosquitoes, constituting a major part of mosquito species diversity. Despite their potential role in arbovirus transmission, the viromes of sylvatic mosquitoes remain largely unexplored. These mosquitoes may also harbor insect-specific viruses (ISVs), affecting arboviral transmission dynamics. The Cerrado biome, known for rapid deforestation and its status as a biodiversity hotspot, offers an ideal setting for investigating mosquito viromes due to potential zoonotic spillover risks from land use changes. This study aimed to characterize the viromes of sylvatic mosquitoes collected from various locations within Minas Gerais state, Brazil. The total RNA was extracted from mosquito pools of Psorophora albipes, Sabethes albiprivus, Sa. chloropterus, Psorophora ferox, and Coquillettidia venezuelensis species, followed by high-throughput sequencing (HTS). Bioinformatic analysis included quality control, contig assembly, and viral detection. Sequencing data analysis revealed 11 near-complete viral genomes (new viruses are indicated with asterisks) across seven viral families and one unassigned genus. These included: Xinmoviridae (Ferox mosquito mononega-like virus* and Albipes mosquito Gordis-like virus*), Phasmaviridae (Sabethes albiprivus phasmavirus*), Lispiviridae (Pedras lispivirus variant MG), Iflaviridae (Sabethes albiprivus iflavivirus*), Virgaviridae (Buriti virga-like virus variant MG and Sabethes albiprivus virgavirus 1*), Flaviviridae (Psorophora ferox flavivirus*), Mesoniviridae (Alphamesonivirus cavallyense variant MG), and the genus Negevirus (Biggie virus variant MG virus and Coquillettidia venezuelensis negevirus*). Moreover, the presence of ISVs and potential novel arboviruses underscores the need for ongoing surveillance and control strategies to mitigate the risk of emerging infectious diseases.


Subject(s)
Arbovirus Infections , Arboviruses , Culicidae , Mosquito Vectors , Phylogeny , Virome , Animals , Brazil , Arboviruses/genetics , Arboviruses/classification , Arboviruses/isolation & purification , Virome/genetics , Culicidae/virology , Arbovirus Infections/transmission , Arbovirus Infections/virology , Mosquito Vectors/virology , Genome, Viral , High-Throughput Nucleotide Sequencing , Insect Viruses/genetics , Insect Viruses/classification , Insect Viruses/isolation & purification
12.
Rev. argent. cir ; 116(3): 201-208, ago. 2024.
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1575955

ABSTRACT

RESUMEN Antecedentes: En las últimas décadas ha habido un cambio considerable hacia un enfoque más conservador en el tratamiento del traumatismocerrado de abdomen, con énfasis en la preservación de la función de órganos; actualmente, el tratamiento no operatorio (TNO) se ha convertido en la técnica de manejo estándar en pacientes hemodinámicamente estables con lesiones de órgano sólido. Objetivo: Describir las variables clínicas asociadas a la tasa de éxito en una serie de pacientes con TNO de trauma abdominal cerrado con lesión de órganos sólidos. Material y métodos: Estudio retrospectivo, observacional, longitudinal, analítico entre enero de 2017 y diciembre de 2022, sobre pacientes admitidos con diagnóstico de traumatismo abdominal cerrado. Las variables evaluadas fueron: edad, sexo, estadía hospitalaria, complicaciones, requerimiento de transfusiones, tasa de éxito y mortalidad. Resultados: De 2590 pacientes ingresados por Guardia de Cirugía General, 24 pacientes se internaron con diagnóstico de traumatismo cerrado de abdomen. Fueron excluidos 15 pacientes por no cumplir con los criterios de inclusión. Los 9 pacientes seleccionados tuvieron un promedio de edad de 39 años (15-80) y 9 fueron varones. En el 36% presentaron lesiones esplénicas grados I-II, 27% presentó lesión renal grado II y el 18% restante con lesión hepática grado II. La tasa de éxito del tratamiento fue del 100% en nuestra serie sin evidenciar fallos en la terapéutica instaurada. Conclusión: Con los criterios empleados en TNO del traumatismo abdominal cerrado con lesión de órganos sólidos fue factible y permitió alcanzar una alta tasa de éxito, sin mortalidad.


ABSTRACT Background: In recent decades, there has been a significant shift toward a more conservative approach to the management of blunt abdominal trauma with an emphasis on preserving organ function; currently, non-operative management (NOM) has become the standard of care for hemodynamically stable patients with solid organ injury. Objective: The aim of this study was to determine the different clinical variables associated with the success rate of NOM of blunt abdominal trauma with involving solid organs. Material and methods: We conducted a retrospective, observational, longitudinal, and analytical study of patients admitted for blunt abdominal trauma between January 1, 2017, and December 1, 2022. The variables evaluated were age, sex, length of hospital stay, complications, transfusion requirements, success rate and mortality. Results: Between January 2017 and December 2022, of 2590 patients seen in the emergency department, 24 were admitted with a diagnosis of blunt abdominal trauma. Fifteen patients did not meet the inclusion criteria. The mean age of the 9 patients included was 39 years (15-80 years) and 6 were men. Thirty-six percent had grade I and II splenic lesions, 27% had grade II renal lesions, and 18% had grade II hepatic lesions. The success rate of our series was 100% and there were no failures. Conclusion: The variables analyzed allowed us to affirm that NOM of blunt abdominal trauma with solid organ injury was feasible and allowed us to achieve a high success rate, without deaths.

13.
Sci Rep ; 14(1): 15456, 2024 07 04.
Article in English | MEDLINE | ID: mdl-38965317

ABSTRACT

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.


Subject(s)
Fungi , Microbiota , Nematoda , Plant Leaves , Plant Leaves/microbiology , Plant Leaves/parasitology , Animals , Nematoda/microbiology , Fungi/classification , Fungi/genetics , Fungi/isolation & purification , Endophytes/genetics , Endophytes/isolation & purification , Yeasts/classification , Yeasts/isolation & purification , Yeasts/genetics , Metagenomics/methods , Biodiversity
14.
Food Res Int ; 191: 114687, 2024 Sep.
Article in English | MEDLINE | ID: mdl-39059945

ABSTRACT

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.


Subject(s)
Fruit , Metabolome , Plant Proteins , Proteome , Fruit/growth & development , Fruit/metabolism , Proteome/metabolism , Plant Proteins/metabolism , Gene Expression Regulation, Plant
15.
AoB Plants ; 16(4): plae037, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38993261

ABSTRACT

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.

16.
J Environ Manage ; 365: 121576, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38955045

ABSTRACT

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.


Subject(s)
Conservation of Natural Resources , Grassland , Brazil , Poaceae/growth & development , Ecosystem , Introduced Species
17.
Plants (Basel) ; 13(13)2024 Jul 03.
Article in English | MEDLINE | ID: mdl-38999672

ABSTRACT

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.

18.
Food Res Int ; 188: 114500, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38823879

ABSTRACT

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.


Subject(s)
Coffea , Potassium , Brazil , Coffea/chemistry , Coffea/growth & development , Potassium/analysis , Seeds/chemistry , Seeds/growth & development , Coffee/chemistry , Taste , Fertilizers , Humans , Caffeine/analysis
19.
Mol Ecol ; 33(14): e17431, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38877815

ABSTRACT

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.


Subject(s)
Phylogeography , Climate Change , South America , Biodiversity , Tropical Climate
20.
Plant Biol (Stuttg) ; 2024 Jun 28.
Article in English | MEDLINE | ID: mdl-38940062

ABSTRACT

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.

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