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1.
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
2.
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.

3.
Braz. j. biol ; 842024.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469324

RESUMO

Abstract Caryocar brasiliense Camb. (Malpighiales: Caryocaraceae) trees are widely distributed throughout the Cerrado ecosystem. The fruits of C. brasiliense trees are used by humans for food and as the main income source in many communities. C. brasiliense conservation is seriously threatened due to habitat loss caused by the land-use change. Sucking insects constitute an important ecological driver that potentially impact C. brasiliense survival in degraded environments. In addition, insects sampling methodologies for application in studies related to the conservation of C. brasiliense are poorly developed. In this study, sucking insects (Hemiptera) and their predators were recorded in three vertical strata of Caryocar brasiliense canopies. The distribution of sucking species showed vertical stratification along the canopy structure of C. brasiliense. The basal part of the canopy had the highest numbers of sucking insects Aphis gossypii (Glover 1877) (Hemiptera: Aphididae) and Bemisia tabaci (Genn. 1889) (Hemiptera: Aleyrodidae), and their predators Chrysoperla sp. (Neuroptera: Chrysopidae), spiders (Araneae), and Zelus armillatus (Lep. & Servi., 1825) (Hemiptera: Reduviidae). Predators' distribution follows the resource availability and preferred C. brasiliense tree parts with a higher abundance of prey.


Resumo Caryocar brasiliense Camb. (Malpighiales: Caryocaraceae) é amplamente distribuído por todo o ecossistema de cerrado. Os frutos de C. brasiliense são utilizados na alimentação humana e constitui uma importante fonte de renda para muitas comunidades. A perda de habitat provocada pelas mudanças de uso da terra coloca em risco a conservação de C. brasiliense. Insetos sugadores constituem um importante fator ecológico que, potencialmente, afeta o fitness de C. brasiliense em ambientes degradados. Além disso, as metodologias de amostragem de insetos para aplicação em estudos relacionados à conservação de C. brasiliense são pouco desenvolvidas. Neste estudo, o número de insetos sugadores (Hemiptera) e seus predadores foram avaliados em três estratos verticais do dossel de C. brasiliense. A distribuição das espécies sugadoras apresentou estratificação vertical ao longo da estrutura do dossel. O estrato basal do dossel apresentou o maior número de insetos sugadores Aphis gossypii (Glover 1877) (Hemiptera: Aphididae) e Bemisia tabaci (Genn. 1889) (Hemiptera: Aleyrodidae), e seus predadores Chrysoperla sp. (Neuroptera: Chrysopidae), aranhas (Araneae) e Zelus armillatus (Lep. & Servi., 1825) (Hemiptera: Reduviidae). Os predadores distribuíram-se de acordo com a disponibilidade de recursos, ocorrendo em maior número nas partes do dossel com maior abundância de suas presas.

4.
Braz. j. biol ; 84: e253598, 2024. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1355857

RESUMO

Abstract Caryocar brasiliense Camb. (Malpighiales: Caryocaraceae) trees are widely distributed throughout the Cerrado ecosystem. The fruits of C. brasiliense trees are used by humans for food and as the main income source in many communities. C. brasiliense conservation is seriously threatened due to habitat loss caused by the land-use change. Sucking insects constitute an important ecological driver that potentially impact C. brasiliense survival in degraded environments. In addition, insects sampling methodologies for application in studies related to the conservation of C. brasiliense are poorly developed. In this study, sucking insects (Hemiptera) and their predators were recorded in three vertical strata of Caryocar brasiliense canopies. The distribution of sucking species showed vertical stratification along the canopy structure of C. brasiliense. The basal part of the canopy had the highest numbers of sucking insects Aphis gossypii (Glover 1877) (Hemiptera: Aphididae) and Bemisia tabaci (Genn. 1889) (Hemiptera: Aleyrodidae), and their predators Chrysoperla sp. (Neuroptera: Chrysopidae), spiders (Araneae), and Zelus armillatus (Lep. & Servi., 1825) (Hemiptera: Reduviidae). Predators' distribution follows the resource availability and preferred C. brasiliense tree parts with a higher abundance of prey.


Resumo Caryocar brasiliense Camb. (Malpighiales: Caryocaraceae) é amplamente distribuído por todo o ecossistema de cerrado. Os frutos de C. brasiliense são utilizados na alimentação humana e constitui uma importante fonte de renda para muitas comunidades. A perda de habitat provocada pelas mudanças de uso da terra coloca em risco a conservação de C. brasiliense. Insetos sugadores constituem um importante fator ecológico que, potencialmente, afeta o fitness de C. brasiliense em ambientes degradados. Além disso, as metodologias de amostragem de insetos para aplicação em estudos relacionados à conservação de C. brasiliense são pouco desenvolvidas. Neste estudo, o número de insetos sugadores (Hemiptera) e seus predadores foram avaliados em três estratos verticais do dossel de C. brasiliense. A distribuição das espécies sugadoras apresentou estratificação vertical ao longo da estrutura do dossel. O estrato basal do dossel apresentou o maior número de insetos sugadores Aphis gossypii (Glover 1877) (Hemiptera: Aphididae) e Bemisia tabaci (Genn. 1889) (Hemiptera: Aleyrodidae), e seus predadores Chrysoperla sp. (Neuroptera: Chrysopidae), aranhas (Araneae) e Zelus armillatus (Lep. & Servi., 1825) (Hemiptera: Reduviidae). Os predadores distribuíram-se de acordo com a disponibilidade de recursos, ocorrendo em maior número nas partes do dossel com maior abundância de suas presas.


Assuntos
Humanos , Animais , Afídeos , Malpighiales , Árvores , Ecossistema , Insetos
5.
Animals (Basel) ; 13(24)2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-38136797

RESUMO

The Brazilian merganser (Mergus octosetaceus) is one of the most endangered bird species in South America and comprises less than 250 mature individuals in wild environments. This is a species extremely sensitive to environmental disturbances and restricted to a few "pristine" freshwater habitats in Brazil, and it has been classified as Critically Endangered on the IUCN Red List since 1994. Thus, biological conservation studies are vital to promote adequate management strategies and to avoid the decline of merganser populations. In this context, to understand the evolutionary dynamics and the current genetic diversity of remaining Brazilian merganser populations, we used the "Genotyping by Sequencing" approach to genotype 923 SNPs in 30 individuals from all known areas of occurrence. These populations revealed a low genetic diversity and high inbreeding levels, likely due to the recent population decline associated with habitat loss. Furthermore, it showed a moderate level of genetic differentiation between all populations located in four separated areas of the highly threatened Cerrado biome. The results indicate that urgent actions for the conservation of the species should be accompanied by careful genetic monitoring to allow appropriate in situ and ex situ management to increase the long-term species' survival in its natural environment.

6.
Genetica ; 151(6): 357-367, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37922114

RESUMO

There has been a continuous interest in understanding the patterns of genetic diversity in natural populations because of the role of intraspecific genetic diversity as the basis of all evolutionary change and thus, its potential effects on population persistence when facing environmental changes. Here, we provided the first description of genetic diversity distribution and population structure of Anacardium occidentale L. (cashew) from the Brazilian Cerrado, one of the most economically important tropical crops in the world. We applied Bayesian clustering approaches (STRUCTURE and POPS) that allow predicting the effects of future climatic changes on the population genetic structure of A. occidentale. We identified distinct genetic groups corresponding to the southwestern, central, and northern regions of the species' range. The characterized genetic clusters will disappear under future climate change scenarios, leading to a homogenization of genetic variability across the landscape. Our findings suggest a high likelihood for the loss of genetic diversity, which in turn will reduce the evolutionary potential of the species to cope with predicted future climatic changes. Results from this study may help develop management strategies to conserve the genetic diversity and structure of natural cashew populations.


Assuntos
Anacardium , Mudança Climática , Brasil , Teorema de Bayes , Ecossistema , Genética Populacional , Variação Genética
7.
Ecol Evol ; 13(11): e10752, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38020699

RESUMO

Dung beetles are efficient indicators to obtain responses regarding the effects of land use change on biodiversity. Although the biological consequences of Cerrado conversion into pasture have been observed at the assemblage scale, there are no cues regarding the effects of tropical savanna conversion into pasture on physiological condition of dung beetle individuals. In this study, we evaluated whether native and non-native habitats in Cerrado affect the physiological condition and body traits of males and females of Phanaeus palaeno. The individuals were collected from a Cerrado fragment (sensu stricto) and an exotic pasture (Urochloa spp.). Physiological condition was assessed through the estimation of individuals' dry body mass, fat mass, and muscle mass. Body traits were estimated through individual body size and males' horn length. We did not find differences between dung beetle morphological traits between Cerrado and pastures. However, individuals collected in exotic pastures had lower dry mass and fat mass, but higher muscle mass, than in conserved Cerrado. Understanding how the land use change affects individuals' body condition is essential to maintain abundant and healthy populations of dung beetles in human-modified landscapes. Although the estimation of physiological condition is logistically more complex than species body traits, future studies aiming to present complex and finer ecological responses of dung beetles should incorporate physiological data to their approaches.

8.
Front Chem ; 11: 1267634, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37795387

RESUMO

Introduction: The green revolution model that is followed in the Brazilian Cerrado is dependent on mechanization, chemical fertilization for soil dressing and correction, and the use of herbicides. Paraquat is a methyl viologen herbicide marketed as bipyridylium dichloride salts and used (in low doses) to combat weeds in their post-emergence stage. It is a non-selective pesticide that causes the peroxidation of the lipids that make up the cell membrane, and when it comes into contact with foliage, it results in the death of the plant. Methods: The effect of water molecules co-crystallized in Paraquat salt structures was analyzed in anhydrous, dihydrate, and trihydrate forms to understand those physicochemical properties in its redox activity. The frontier molecular orbitals were also carried out using DFT to obtain the chemical reactivity of the bipyridylium cation. Finally, the supramolecular arrangements were evaluated to analyze the physicochemical stability and acquire insights on superoxide anions. Results and discussion: The electronic structure indicated that the BP cation presents an acidic character due to its low ELUMO value, while the salt has a more basic character due to its high EHOMO value. For this reason, the BP ion is more susceptible to reduction during the weeds' photosynthesis process. During the process of plant photosynthesis, PQ is reduced to form a stable radical cation. In the supramolecular arrangement, the presence of water molecules increases the number of strong H-bonds, while the weak/moderate H-bonds are stabilized. PQ's toxic effects are observed in wildlife, domesticated animals, human populations, and ecosystems. The influence of PQ on the terrestrial environment is limited because of the soil adsorption capacity associated with good agricultural practices. The current use of good agricultural practices in the Cerrado seems not to prevent the environmental impacts of herbicides like PQ because it aims for the expansion and profitability of large-scale farming based on input-intensive practices instead of sustainable agriculture processes.

9.
Artigo em Inglês | MEDLINE | ID: mdl-37671634

RESUMO

The relationship between agriculture and wildlife can be both synergetic and challenging, as the increased surface of agricultural land makes it increasingly important for agriculture and wildlife to coexist. This study aims to describe the use of freshly drilled dry bean fields by birds and mammals in Brazilian Cerrado and Atlantic Forest sites and their diversity and abundance within in-crop and off-crop areas (with native permanent vegetation and other surrounding crop fields) at four different farms. A comprehensive survey was conducted, using various sampling methods, including point counts, foraging counts, trail cameras, and occasional encounters. In all, contacts for 12 518 birds across 306 species and 313 mammals across 34 species were registered. The off-crop areas exhibited greater species richness, abundance, and diversity than the in-crop areas on all farms. For birds, 47 species were recorded in-crop, of which 15 were classified as insectivores, 15 as granivores, seven as omnivores, seven as carnivores, and three as frugivores. The number of in-crop observations per species was small. The abundance off-crop was greater for 31 species observed in-crop, indicating that dry bean fields are probably not a preferred habitat for those species. Species classified as granivorous are most likely to feed on dry bean seeds. However, almost all granivorous species observed in-crop areas are too small to be able to feed on dry bean seeds. For mammals, nine species were recorded in-crop, of which four were classified as carnivores, three as omnivores, one as insectivore, and one as granivore. Additionally, despite the considerable effort in this study, no evidence was found that birds and mammals feed on dry bean seeds. The results highlight the importance of off-crop areas in dry bean fields, characterized by a more diverse and abundant bird community than in-crop. Integr Environ Assess Manag 2023;00:1-11. © 2023 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

10.
Front Pharmacol ; 14: 1223933, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37654604

RESUMO

Doxorubicin (Dox) is a chemotherapeutic agent widely used in the clinic, whose side effects include cardiotoxicity, associated with decreased antioxidant defenses and increased oxidative stress. The association of Dox with natural antioxidants can extend its use if not interfering with its pharmacological potential. In this study, we aimed to understand the effects and mechanisms of the aqueous extract of Acrocomia aculeata leaves (EA-Aa) in cancer cells and the co-treatment with Dox, in in vitro and in vivo models. It was found that EA-Aa showed a relevant decrease in the viability of cancer cells (K562 and MCF-7) and increased apoptosis and death. The Dox cytotoxic effect in co-treatment with EA-Aa was increased in cancer cells. The therapeutic association also promoted a change in cell death, leading to a higher rate of apoptosis compared to the Dox group, which induced necrosis. In addition, in non-cancer cells, EA-Aa enhanced red blood cell (RBC) redox state with lower hemolysis and malondialdehyde (MDA) content and had no in vitro nor in vivo toxicity. Furthermore, EA-Aa showed antioxidant protection against Dox-induced cytotoxicity in H9c2 cells (cardiomyoblast), partially mediated by the NRF2 pathway. In vivo, EA-Aa treatment showed a relevant decrease in MDA levels in the heart, kidney, and brain, evaluated in C57Bl/6 mice induced to cardiotoxicity by Dox. Together, our results proved the effectiveness of EA-Aa in potentiating Dox anticancer effects, with antioxidant and cardioprotective activity, suggesting EA-Aa as a potential Dox pharmacological adjuvant.

11.
Plants (Basel) ; 12(13)2023 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-37447015

RESUMO

New agricultural practices and land-use intensification in the Cerrado biome have affected the soil carbon stocks. A major part of the native vegetation of the Brazilian Cerrado, a tropical savanna-like ecoregion, has been replaced by crops, which has caused changes in the soil carbon (C) stocks. To ensure the sustainability of this intensified agricultural production, actions have been taken to increase soil C stocks and mitigate greenhouse gas emissions. In the last two decades, new agricultural practices have been adopted in the Cerrado region, and their impact on C stocks needs to be better understood. This subject has been addressed in a systematic review of the existing data in the literature, consisting of 63 articles from the Scopus database. Our review showed that the replacement of Cerrado vegetation by crop species decreased the original soil C stocks (depth 0-30 cm) by 73%, with a peak loss of 61.14 Mg ha-1. However, when analyzing the 0-100 cm layer, 52.4% of the C stock data were higher under cultivated areas than in native Cerrado soils, with a peak gain of 93.6 Mg ha-1. The agricultural practices implemented in the Brazilian Cerrado make low-carbon agriculture in this biome possible.

12.
Sci Total Environ ; 888: 164119, 2023 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-37182782

RESUMO

Centre-pivot systems are widely used for irrigation in agriculture. However, excessive water application rates under low pressure centre-pivot systems can lead to soil erosion, which degrades soil structure and increases crop vulnerability to droughts. Although efforts have been deployed to measure soil erosion underneath individual centre pivots, a large-scale systematic assessment of extent and severity of soil erosion in centre-pivot irrigated fields is currently lacking. Here we used Google Earth™ satellite images to provide first evidence of widespread, severe soil erosion in centre-pivot irrigated agricultural land. We focused on the municipality of Cristalina (6154 km2), in the Brazilian Central Highlands, where centre pivots irrigate approximately 60,000 ha of cropland. The study area is in the Cerrado biome, which is one of the most important grain-producing regions in the world and Brazil's main centre-pivot irrigation area. By mapping erosion features under centre pivots, we found that 29 % of centre-pivot fields displayed signs of rill erosion, with individual rills up to a length of 1200 m. Most erosion features were identified during the dry season of the Brazilian Cerrado, which coincided with the period of greater satellite-image availability. Moreover, we found that compacted centre-pivot-wheel tracks often triggered rill incision and that eroding centre-pivot fields displayed higher slope gradients and were better connected to surface waters than the non-eroding fields. Ultimately, the frequent identification of severe erosion features in the centre-pivot fields during the dry season indicates that irrigation causes and/or aggravates soil erosion in Cristalina and likely in other parts of the Brazilian Cerrado. This first systematic evidence of widespread soil erosion underneath centre-pivot systems highlights that irrigation erosion is an important but neglected driver of land degradation, and that urgent action is required to protect affected soils for future generations.

13.
Animals (Basel) ; 13(8)2023 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-37106851

RESUMO

Brazilian spotted fever (BSF) is the most important tick-borne diseases affecting humans in Brazil. Cases of BSF have recently been reported in the Goiás state, midwestern Brazil. All cases have been confirmed by reference laboratories by seroconversion to Rickettsia rickettsii antigens. Because serological cross-reactions among different rickettsial species that belong to the spotted fever group (SFG) are common, the agent responsible for BSF cases in Goiás remains unknown. From March 2020 to April 2022, ticks and plasma were collected from dogs, horses and capybaras (Hydrochoerus hydrochaeris), and from the vegetation in an area where BSF cases have been reported and two areas under epidemiological surveillance in Goiás. Horses were infested by Amblyomma sculptum, Dermacentor nitens and Rhipicephalus microplus; dogs by Rhipicephalus sanguineus sensu lato (s.l.), Amblyomma ovale and A. sculptum, and capybaras by A. sculptum and Amblyomma dubitatum. Adults of A. sculptum, A. dubitatum, Amblyomma rotundatum and immature stages of A. sculptum and A. dubitatum, and Amblyomma spp. were collected from the vegetation. DNA of Rickettsia that did not belong to the SFG was detected in A. dubitatum, which was identified by DNA sequencing as Rickettsia bellii. Seroreactivity to SFG and Rickettsia bellii antigens was detected in 25.4% (42/165) of dogs, 22.7% (10/44) of horses and 41.2% (7/17) of capybaras, with higher titers for R. bellii in dogs and capybaras. The seropositivity of animals to SFG Rickettsia spp. antigens demonstrates the circulation of SFG rickettsiae in the region. Further research is needed to fully determine the agent responsible for rickettsiosis cases in this area.

14.
Biomed Pharmacother ; 161: 114498, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36906973

RESUMO

In a screening of a small library of extracts from plants of the Amazonian and Cerrado biomes, a hexane extract of Connarus tuberosus roots was found to significantly potentiate the GABA induced fluorescence in a fluorescence (FLIPR) assay in CHO cells stably expressing the α1ß2γ2 subtype of human GABAA receptors. With the aid of HPLC-based activity profiling the activity was linked to the neolignan connarin. In CHO cells the activity of connarin was not abolished by increasing concentrations of flumazenil, while the effect of diazepam was increased by increasing concentrations of connarin. The effect of connarin was abolished by pregnenolone sulfate (PREGS) in a concentration-dependent manner, and the effect of allopregnanolone was further increased by increasing concentrations of connarin. In a two-microelectrode voltage clamp assay with Xenopus laevis oocytes transiently expressing GABAA receptors composed of human α1ß2γ2S and α1ß2 subunits connarin potentiated the GABA-induced currents, with EC50 values of 1.2 ± 0.3 µM (α1ß2γ2S) and 1.3 ± 0.4 µM (α1ß2), and with a maximum enhancement of currents Emax of 1959 ± 70% (α1ß2γ2S) and 185 ± 48% (α1ß2). The activation induced by connarin was abolished by increasing concentrations of PREGS.


Assuntos
Connaraceae , Neuroesteroides , Animais , Cricetinae , Humanos , Receptores de GABA-A/metabolismo , Neuroesteroides/metabolismo , Moduladores GABAérgicos/farmacologia , Cricetulus , Sítios de Ligação , Ácido gama-Aminobutírico/farmacologia , Ácido gama-Aminobutírico/metabolismo , Oócitos
15.
Am J Bot ; 110(4): e16146, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36826405

RESUMO

PREMISE: Understanding tree species' responses to drought is critical for predicting the future of tropical forests, especially in regions where the climate is changing rapidly. METHODS: We compared anatomical and functional traits of the dominant tree species of two tropical forests in southern Amazonia, one on deep, well-drained soils (cerradão [CD]) and one in a riparian environment (gallery forest [GF]), to examine potential anatomical indicators of resistance or vulnerability to drought. RESULTS: Leaves of CD species generally had a thicker cuticle, upper epidermis, and mesophyll than those of GF species, traits that are indicative of adaptation to water deficit. In the GF, the theoretical hydraulic conductivity of the stems was significantly higher, indicating lower investment in drought resistance. The anatomical functional traits of CD species indicate a greater potential for surviving water restriction compared to the GF. Even so, it is possible that CD species could also be affected by extreme climate changes due to the more water-limited environment. CONCLUSIONS: In addition to the marked anatomical and functional differences between these phytophysiognomies, tree diversity within each is associated with a large range of hydraulic morphofunctional niches. Our results suggest the strong potential for floristic and functional compositional shifts under continued climate change, especially in the GF.


Assuntos
Árvores , Água , Árvores/fisiologia , Água/fisiologia , Clima Tropical , Florestas , Secas , Folhas de Planta/fisiologia
16.
J Environ Manage ; 330: 117185, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36603271

RESUMO

The Cerrado region comprises the world's most biodiverse savanna and the largest cultivated pastures for cattle in Brazil. Forty percent of these pastures are unproductive or degraded, with bare soil and native vegetation increasingly replacing exotic forage grasses. This study sought to investigate the regeneration of native vegetation in the pastures of the Cerrado and to evaluate the contribution of biophysical, land management, and landscape attributes to this process. Across the Cerrado, we analyzed pasture plant communities and the attributes of pasture management intensification, fire events, landscape native vegetation cover, and climate and soil types of 93 active pastures and 15 abandoned pastures. For the abandoned pastures, time since abandonment was an additional variable. On actively cultivated pastures, savanna regeneration varied from 0 to 70%, with a diversity of herbs and woody species. Pasture management was the main predictor of savanna regeneration on cultivated pastures. On abandoned pastures, time since abandonment was the main predictor. Exotic grass cover had a strong negative relationship with savanna regeneration and they were present even in pastures abandoned for 44 years. Our study reveals the potential of natural regeneration of the Cerrado and its particular predictors. The occurrence of pastures with high natural regeneration indicates that national policies can promote native vegetation restoration and silvopastoral systems with predictable, low cost implementation.


Assuntos
Ecossistema , Pradaria , Animais , Bovinos , Florestas , Biodiversidade , Solo , Poaceae , Brasil
17.
Nat Prod Res ; 37(1): 119-122, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34227418

RESUMO

Essential oils (EOs) of Eugenia dysenterica fruits from seven populations were assessed using GC/MS and chemometric analysis. Variations in EOs between populations and three operational chemical units (OCUs), combined with foliar Mn2+ as an environmental variable, indicate that 86.8% of variation in oils was explained by these predictors. Variance partitioning shows that the largest pure contribution was attributed to foliar Mn2+ (13.1%), followed by OCU (11.4%). Populational origin contributed with lowest variance (6.6%).


Assuntos
Eugenia , Óleos Voláteis , Frutas , Extratos Vegetais
18.
Sci Total Environ ; 862: 160674, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36493825

RESUMO

No-till (NT) as a conservation practice aims to minimize soil disturbance and enhance soil sustainability. However, how NT practice affects soil physicochemical and biological properties in soybean areas remains unclear. This study selected 65 high-yielding soybean farms under a long-term NT system in the Brazilian Cerrado and collected soil samples at 0.0-0.10 m (L1), 0.10-0.20 m (L2) and 0.20-0.40 m (L3) depths. The effect of NT on soil properties and interactions with soybean productivities were assessed. Results showed that the average soybean yield of the study areas in the last three years was 4.13 Mg ha-1, with 26 areas presenting yields over 4.20 Mg ha-1. Most studied soil properties showed a depth stratification and were strongly concentrated in L1, except for S, Al3+ and aluminum saturation, which displayed lower surface and higher subsurface concentrations. Moreover, a high proportion of SOM is composed of light SOM fraction in areas of high soybean yield, with the average SOM values of 39.9, 27.8 and 19.6 g kg-1 in L1, L2 and L3, respectively. Soils under long-term NT present moderate values of enzyme activity compared with the relatively low values under conventional tillage system, especially 94 % of the plots have moderate values of activity of arylsulfatase enzymes. The data presented support the conclusion that NT system can enhance soil fertility and biological quality in soybean cultivation. Our results suggest that it is necessary to adopt NT practice because it allows increasing soybean productivity in Brazil without the need to increase the sown area, in addition to increasing productivity associated with an improvement in the agroecosystem quality, thus moving toward a more sustainable agriculture.


Assuntos
Solo , Solo/química , Brasil , Agricultura/métodos , Fenômenos Químicos
19.
Philos Trans R Soc Lond B Biol Sci ; 378(1867): 20210075, 2023 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-36373925

RESUMO

There is high potential for ecosystem restoration across tropical savannah-dominated regions, but the benefits that could be gained from this restoration are rarely assessed. This study focuses on the Brazilian Cerrado, a highly species-rich savannah-dominated region, as an exemplar to review potential restoration benefits using three metrics: net biomass gains, plant species richness and ability to connect restored and native vegetation. Localized estimates of the most appropriate restoration vegetation type (grassland, savannah, woodland/forest) for pasturelands are produced. Carbon sequestration potential is significant for savannah and woodland/forest restoration in the seasonally dry tropics (net biomass gains of 58.2 ± 37.7 and 130.0 ± 69.4 Mg ha-1). Modelled restoration species richness gains were highest in the central and south-east of the Cerrado for savannahs and grasslands, and in the west and north-west for woodlands/forests. The potential to initiate restoration projects across the whole of the Cerrado is high and four hotspot areas are identified. We demonstrate that landscape restoration across all vegetation types within heterogeneous tropical savannah-dominated regions can maximize biodiversity and carbon gains. However, conservation of existing vegetation is essential to minimizing the cost and improving the chances of restoration success. This article is part of the theme issue 'Understanding forest landscape restoration: reinforcing scientific foundations for the UN Decade on Ecosystem Restoration'.


Assuntos
Ecossistema , Pradaria , Florestas , Biodiversidade , Sequestro de Carbono
20.
Braz. j. biol ; 83: 1-13, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1468809

RESUMO

Interactions between endophytic fungi (EFs) and their host plants range from positive to neutral to negative. The results of such interactions can vary depending on the organ of the infected host plant. EFs isolated from the leaves of some species of plants have potential for use as agents to inhibit seed germination and control invasive plants. The objectives of this study were to identify EFs present in the leaves of Copaifera oblongifolia and to evaluate the role of these fungi in seed germination and seedling development. A total of 11 species of EFs were isolated, which were identified using the internal transcribed spacers (ITS) sequence of the nuclear ribosomal DNA. The isolated species of EFs are generalists and probably are transmitted horizontally. Laboratory tests revealed that filtrates of these fungal isolates differently affect seed germination and seedling development of C. oblongifolia. The species Curvularia intermedia, Neofusicoccum parvum, Pseudofusicoccum stromaticum and Phomopsis sp. negatively affected seed germination, with N. parvum standing out for its negative effects, inhibiting seedling germination and survival in 89 and 222%, respectively. In addition, Cochliobolus intermedius negatively affected seedling development. Thus, the combined use of N. parvum and C. intermedius, or products from the metabolism of these microorganisms, in the control of invasive plants deserves attention from future studies.


As interações entre fungos endofíticos (FEs) e suas plantas hospedeiras variam de positivas, neutras a negativas. Os resultados destas interações podem variar dependendo do órgão da planta hospedeira infectada. FEs isolados de folhas de algumas espécies de plantas têm potencial para serem usados como agentes inibidores da germinação de sementes e no controle de plantas invasoras. Os objetivos deste estudo foram identificar os FEs presentes nas folhas de Copaifera oblongifolia e avaliar o papel destes fungos na germinação das sementes e no desenvolvimento das plântulas. Um total de 11 espécies de FEs foi isolado das folhas de C. oblongifolia e identificado através da sequência dos espaçadores internos transcritos do DNA ribossomal nuclear. As espécies de FEs isoladas são generalistas e provavelmente devem ser transmitidas horizontalmente. Os resultados dos testes de germinação mostraram que filtrados destes isolados fúngicos podem afetar diferentemente a germinação das sementes e o desenvolvimento das plântulas de C. oblongifolia. As espécies Curvularia intermedia, Neofusicoccum parvum, Pseudofusicoccum stromaticum e Phomopsis sp. afetaram negativamente a germinação das sementes de C. oblongifolia. Dentre estas espécies devemos destacar que N. parvum reduziu a germinação e a sobrevivência das plântulas em 89 e 222%, respectivamente. Além disso, Cochiliobolus intermedius afetou negativamente o desenvolvimento das plântulas. Assim, o uso combinado de N. parvum e C. intermedius, ou de produtos do metabolismo destas espécies de fungos, têm potencial para serem usados no manejo de plantas invasoras.


Assuntos
Animais , DNA Ribossômico/análise , Fabaceae/crescimento & desenvolvimento , Fungos/patogenicidade , Germinação , Interações entre Hospedeiro e Microrganismos , Plântula/crescimento & desenvolvimento
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