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1.
An Acad Bras Cienc ; 96(2): e20230972, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38747796

RESUMO

There is a marked disparity in the state of knowledge of Holartic x Neotropical species of the freshwater snail family Physidae; the incipiency of data on Neotropical physids reflecting the lower number of dedicated specialists. The gaps in the knowledge on Neotropical physids have led to historical uncertainty about species validity. Revisiting the species is essential to reduce taxonomic impediment and delineating their probable distribution is the first step to attain this purpose. We aimed at critically analyze occurrence records of South American physids, compiled through an intensive search in the literature, biodiversity and molecular databases. We present a provisional characterization of the distribution of this family in South America, considering the probable versus the poorly documented distribution of the species. The critical underrepresentation of South American physids in collections, molecular databases and literature reinforces the role of taxonomic impediment in delaying the advance of the knowledge on species diversity. Malacological collections represented the main source of records, evidencing the relevance of unpublished data associated to specimens to assess distributional information on neglected groups. As most of the species are represented by shells, the reassessment of species identity and distribution must be done, using molecular and anatomical criteria for species delimitation.


Assuntos
Biodiversidade , Animais , América do Sul , Distribuição Animal , Gastrópodes/classificação , Caramujos/classificação
2.
Biol Lett ; 20(5): 20230448, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38716586

RESUMO

Recent molecular taxonomic advancements have expanded our understanding of crocodylian diversity, revealing the existence of previously overlooked species, including the Congo dwarf crocodile (Osteolaemus osborni) in the central Congo Basin rainforests. This study explores the genomic divergence between O. osborni and its better-known relative, the true dwarf crocodile (Osteolaemus tetraspis), shedding light on their evolutionary history. Field research conducted in the northwestern Republic of the Congo uncovered a locality where both species coexist in sympatry/syntopy. Genomic analysis of sympatric individuals reveals a level of divergence comparable to that between ecologically similar South American dwarf caimans (Paleosuchus palpebrosus and Paleosuchus trigonatus), suggesting parallel speciation in the Afrotropics and Neotropics during the Middle to Late Miocene, 10-12 Ma. Comparison of the sympatric and allopatric dwarf crocodiles indicates no gene flow between the analysed sympatric individuals of O. osborni and O. tetraspis. However, a larger sample will be required to answer the question of whether or to what extent these species hybridize. This study emphasizes the need for further research on the biology and conservation status of the Congo dwarf crocodile, highlighting its significance in the unique biodiversity of the Congolian rainforests and thus its potential as a flagship species.


Assuntos
Jacarés e Crocodilos , Animais , Jacarés e Crocodilos/genética , Jacarés e Crocodilos/anatomia & histologia , Jacarés e Crocodilos/classificação , Congo , Simpatria , América do Sul , Filogenia , Especiação Genética
3.
Nutrients ; 16(9)2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38732642

RESUMO

Vernonia cinerea (L.) Less. is a perennial herbaceous plant found mainly in tropical areas, particularly in Southeast Asia, South America, and India. Various parts of V. cinerea have traditionally been used in folk medicine to treat several diseases, such as malaria, fever, and liver diseases. V. cinerea has so far yielded about 92 secondary metabolites. The majority of these are sesquiterpene lactones, but triterpenes, flavonoids, steroids, phenolics, and other compounds are present as well. V. cinerea crude extracts reportedly exhibit anti-inflammatory, antiprotozoal, antidiabetic, anticancer, antimicrobial, antioxidant, and renoprotective activities. This study aims to provide the latest up-to-date information on the botanical characterization, distribution, traditional uses, phytochemistry, and pharmacological activity of V. cinerea. Information on V. cinerea was thoroughly reviewed. The literature published between 1950 and 2024 was compiled through online bibliographic databases, including SciFinder, Web of Science, Google Scholar, PubMed, ScienceDirect, Springer Link, Wiley, and the MDPI online library. The keywords used for the literature search included Vernonia cinerea (L.) Less. and the synonyms Cyanthillium cinereum (L.) H.Rob., Conyza cinerea L., and various others.


Assuntos
Medicina Tradicional , Compostos Fitoquímicos , Extratos Vegetais , Vernonia , Vernonia/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Humanos , Compostos Fitoquímicos/farmacologia , Fitoterapia , Animais , América do Sul , Sudeste Asiático
4.
Mar Pollut Bull ; 202: 116384, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38643585

RESUMO

Micropogonias furnieri and Urophycis brasiliensis are two coastal demersal fish species distributed in the southwestern Atlantic Ocean. Considering that many coastal areas in the southwestern Atlantic Ocean suffer from anthropogenic pressure, the aim of this study was to assess the level of potentially toxic trace elements (Ag, Al, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, Se, Sr, V and Zn) in the muscle of coastal species, and evaluated the human health risk related to the consumption of muscle. Mercury, inorganic As (Asi), V, and Se showed a higher contribution to the total THQ. Considering two possible scenarios, Asi represents 1 % or 5 % of the total As, the total THQ was <1 for general population and of some health concerns for fishermen population (Total THQ > 1; 5 % Asi). Consequently these results show the importance of quantifying As species in muscle to generate more reliable risk estimates for human health.


Assuntos
Peixes , Músculos , Oligoelementos , Poluentes Químicos da Água , Animais , Medição de Risco , Oligoelementos/análise , Humanos , Poluentes Químicos da Água/análise , Músculos/química , Oceano Atlântico , Monitoramento Ambiental , Contaminação de Alimentos/análise , América do Sul , Alimentos Marinhos
5.
PeerJ ; 12: e17232, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38646479

RESUMO

The species richness in the Neotropics has been linked to environmental heterogeneity and a complex geological history. We evaluated which biogeographic processes were associated with the diversification of Monkey tree frogs, an endemic clade from the Neotropics. We tested two competing hypotheses: the diversification of Phyllomedusinae occurred either in a "south-north" or a "north-south" direction in the Neotropics. We also hypothesized that marine introgressions and Andean uplift had a crucial role in promoting their diversification. We used 13 molecular markers in a Bayesian analysis to infer phylogenetic relationships among 57 species of Phyllomedusinae and to estimate their divergence times. We estimated ancestral ranges based on 12 biogeographic units considering the landscape modifications of the Neotropical region. We found that the Phyllomedusinae hypothetical ancestor range was probably widespread throughout South America, from Western Amazon to Southern Atlantic Forest, at 29.5 Mya. The Phyllomedusines' ancestor must have initially diverged through vicariance, generally followed by jump-dispersals and sympatric speciation. Dispersal among areas occurred mostly from Western Amazonia towards Northern Andes and the South American diagonal of dry landscapes, a divergent pattern from both "south-north" and "north-south" diversification hypotheses. Our results revealed a complex diversification process of Monkey tree frogs, occurring simultaneously with the orogeny of Northern Andes and the South American marine introgressions in the last 30 million years.


Assuntos
Anuros , Teorema de Bayes , Filogenia , Animais , Anuros/genética , Anuros/classificação , América do Sul , Filogeografia , Especiação Genética
6.
Ying Yong Sheng Tai Xue Bao ; 35(3): 797-805, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38646768

RESUMO

Phthorimaea operculella is a major potato pest of global importance, early warning and detection of which are of significance. In this study, we analyzed the climate niche conservation of P. operculella during its invasion by comparing the overall climate niche from three dimensions, including the differences between native range (South America) and entire invaded region (excluding South America), the differences bwtween native range (South America) and five invaded continents (North America, Oceania, Asia, Africa, and Europe), as well as the differences between native region (South America) and an invaded region (China). We constructed ecological niche models for its native range (South America) and invaded region (China). The results showed that the climatic niche of the pest has expanded to varying degrees in different regions, indicating that the pest could well adapt to new environments during the invasion. Almost all areas of South America are suitable for P. operculella. In China, its suitable area is mainly concentrated in Shandong, Hebei, Tianjin, Beijing, Henan, Hubei, Yunnan, Guizhou, Sichuan, Hainan, northern Guangxi, southern Hunan, Anhui, Guangdong, Jiangsu, southern Shanxi, and southern Shaanxi. With increasing greenhouse gas emissions and global temperature, its suitable area will decrease at low latitude and increase gradually at high latitude. Specifically, the northern boundary will extend to Liaoning, Jilin, and the southeastern region of Inner Mongolia, while the western boundary extends to Sichuan and the southeast Qinghai-Tibet Plateau. The suitable area in the southeast Yunnan-Guizhou Plateau, Hainan Island, and the south of Yangtze River, will gradually decrease. The total suitable habitat area for P. operculella in China is projected to increase under future climate condition. From 2081 to 2100, under the three greenhouse gas emissions scenarios of ssp126, ssp370, and ssp585, the suitable area is expected to increase by 27.78, 165.54, and 140.41 hm2, respectively. Therefore, it is crucial to strengtehen vigilance and implement strict measures to prevent the further expansion of P. operculella.


Assuntos
Ecossistema , Espécies Introduzidas , China , Animais , América do Sul , Clima
7.
Int Marit Health ; 75(1): 61-63, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38647061

RESUMO

Myiasis, an infestation caused by dipteran larvae, commonly known as maggots, is one of the most common parasitic skin disorders in the tropical regions. Authors report a case of cutaneous myiasis caused by Dermatobia hominis (Diptera: Oestridae) in a Polish traveller returning from a self-organized trip to South America. Species biology, prophylaxis, and medical implications of this tropical parasitosis are discussed.


Assuntos
Dípteros , Miíase , Viagem , Miíase/diagnóstico , Miíase/parasitologia , Humanos , Animais , Polônia , América do Sul , Masculino , Larva , Adulto , Pessoa de Meia-Idade
8.
Proc Biol Sci ; 291(2021): 20240235, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38654650

RESUMO

Terror birds (Aves, Phorusrhacidae) were large flightless apex predators in South America during the Cenozoic. Here, we estimate a new phylogeny for phorusrhacids using Bayesian inference. We demonstrate phylogenetic evidence for a monophyletic Patagornithinae and find significant support for a distinct crown group associated with the quintessential 'terror bird' characteristics. We use this phylogeny to analyse the evolution of body size and cursoriality. Our results reveal that size overlap was rare between co-occurring subfamilies, supporting the hypothesis that these traits were important for niche partitioning. We observe that gigantism evolved in a single clade, containing Phorusrhacinae and Physornithinae. The members of this lineage were consistently larger than all other phorusrhacids. Phorusrhacinae emerged following the extinction of Physornithinae, suggesting the ecological succession of the apex predator niche. The first known phorusrhacine, Phorusrhacos longissimus, was gigantic but significantly smaller and more cursorial than any physornithine. These traits likely evolved in response to the expansion of open environments. Following the Santacrucian SALMA, phorusrhacines increased in size, further converging on the morphology of Physornithinae. These findings suggest that the evolution and displacement of body size drove terror bird niche partitioning and competitive exclusion controlled phorusrhacid diversity.


Assuntos
Evolução Biológica , Tamanho Corporal , Filogenia , Animais , Passeriformes/fisiologia , Teorema de Bayes , América do Sul , Aves/fisiologia
9.
Arq Bras Cardiol ; 121(3): e20230521, 2024.
Artigo em Português, Inglês | MEDLINE | ID: mdl-38597555

RESUMO

BACKGROUND: Cardiovascular diseases (CVD) have significant health and economic burdens. In South America, the loss of productivity related to these diseases has not yet been well explored. OBJECTIVE: Estimate the potentially productive years of life lost (PPYLL) and loss of productivity related to premature mortality associated with CVD in South America, in 2019. METHODS: Mortality data available from the 2019 Global Burden of Disease Study were used to estimate the burden of disease attributable to CVD. For monetary calculations of productivity loss, a proxy of the human capital approach was used. Data were stratified by sex, in working age groups. RESULTS: The total number of deaths due to CVD in South America in 2019 was 754,324, and the total number of PPYLL was 2,040,973. The total permanent loss of productivity was approximately US$ 3.7 billion and US$ 7.8 billion in purchasing power parity, equivalent to 0.11% of the gross domestic product. The cost per death was US$ 22,904, and the ratio between men and women for the cost per death was 1.45. The variation in scenarios indicates that the estimates are robust, even with important differences between countries. CONCLUSIONS: CVD impose a significant economic burden on countries in South America. The characterization of this burden can support governments in the allocation of resources for the planning and execution of health policies and interventions in promotion, prevention, and recovery.


FUNDAMENTO: As doenças cardiovasculares (DCV) têm ônus sanitário e econômico significativos. Na América do Sul (AS), a perda de produtividade relacionada a estas enfermidades ainda não foi bem explorada. OBJETIVO: Estimar os anos de vida produtiva perdidos (AVPP) e a perda de produtividade relacionados a mortalidade prematura associada as DCV na AS, em 2019. MÉTODOS: Empregou-se dados de mortalidade disponíveis no Global Burden of Disease Study 2019 na estimativa da carga de doença atribuível a DCV. Para os cálculos monetários da perda da produtividade usou-se uma proxy da abordagem de capital humano. Estratificou-se por sexo, nas faixas etárias de trabalho. RESULTADOS: O número total de mortes por DCV na AS no ano de 2019 foi de 754.324 e os AVPP foram 2.040.973. A perda permanente de produtividade total foi de aproximadamente US$ 3,7 bilhões e US$ 7,8 bilhões em paridade do poder de compra, equivalente a 0,11% do produto interno bruto. O custo por morte foi de US$ 22.904, e a razão desse custo por óbito, entre homens e mulheres foi 1,45. A variação dos cenários aponta robustez nas estimativas, mesmo com diferenças importantes entre os países. CONCLUSÕES: As DCV impõem um ônus econômico significativo a este bloco de países. A caracterização deste fardo pode amparar os governos na alocação de recursos destinados ao planejamento e execução de políticas e intervenções sanitárias, sejam de promoção, prevenção ou recuperação.


Assuntos
Doenças Cardiovasculares , Efeitos Psicossociais da Doença , Masculino , Humanos , Feminino , Custos de Cuidados de Saúde , América do Sul/epidemiologia , Eficiência
10.
BMC Microbiol ; 24(1): 115, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38575867

RESUMO

Despite repeated spillover transmission and their potential to cause significant morbidity and mortality in human hosts, the New World mammarenaviruses remain largely understudied. These viruses are endemic to South America, with animal reservoir hosts covering large geographic areas and whose transmission ecology and spillover potential are driven in part by land use change and agriculture that put humans in regular contact with zoonotic hosts.We compiled published studies about Guanarito virus, Junin virus, Machupo virus, Chapare virus, Sabia virus, and Lymphocytic Choriomeningitis virus to review the state of knowledge about the viral hemorrhagic fevers caused by New World mammarenaviruses. We summarize what is known about rodent reservoirs, the conditions of spillover transmission for each of these pathogens, and the characteristics of human populations at greatest risk for hemorrhagic fever diseases. We also review the implications of repeated outbreaks and biosecurity concerns where these diseases are endemic, and steps that countries can take to strengthen surveillance and increase capacity of local healthcare systems. While there are unique risks posed by each of these six viruses, their ecological and epidemiological similarities suggest common steps to mitigate spillover transmission and better contain future outbreaks.


Assuntos
Arenaviridae , Arenavirus do Novo Mundo , Animais , Humanos , Arenaviridae/genética , América do Sul
11.
Sci Data ; 11(1): 336, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38575659

RESUMO

The South American Archaeological Isotopic Database (SAAID) is a comprehensive open-access resource that aggregates all available bioarchaeological stable and radiogenic isotope measurements, encompassing data from human individuals, animals, and plants across South America. Resulting from a collaborative effort of scholars who work with stable isotopes in this region, SAAID contains 53,781 isotopic measurements across 24,507 entries from individuals/specimens spanning over 12,000 years. SAAID includes valuable contextual information on archaeological samples and respective sites, such as chronology, geographical region, biome, and spatial coordinates, biological details like estimated sex and age for human individuals, and taxonomic description for fauna and flora. SAAID is hosted at the PACHAMAMA community within the Pandora data platform and the CORA repository to facilitate easy access. Because of its rich data structure, SAAID is particularly well-suited for conducting spatiotemporal meta-analyses. It serves as a valuable tool for addressing a variety of research topics, including the spread, adoption, and consumption intensification of food items, paleo-environmental reconstruction, as well as the exploration of mobility patterns across extensive geographic regions.


Assuntos
Arqueologia , Isótopos , Animais , Humanos , Ecossistema , América do Sul
13.
Int J Biometeorol ; 68(5): 979-990, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38451371

RESUMO

Yerba mate (Ilex paraguariensis) is renowned for its nutritional and pharmaceutical attributes. A staple in South American (SA) culture, it serves as the foundation for several traditional beverages. Significantly, the pharmaceutical domain has secured numerous patents associated with this plant's distinctive properties. This research delves into the climatic influence on yerba mate by leveraging the CMIP6 model projections to assess potential shifts brought about by climate change. Given its economic and socio-cultural significance, comprehending how climate change might sway yerba mate's production and distribution is pivotal. The CMIP6 model offers insights into future conditions, pinpointing areas that are either conducive or adverse for yerba mate cultivation. Our findings will be instrumental in crafting adaptive and mitigative strategies, thereby directing sustainable production planning for yerba mate. The core objective of this study was to highlight zones optimal for Ilex paraguariensis cultivation across its major producers: Brazil, Argentina, Paraguay, and Uruguay, under CMIP6's climate change forecasts. Our investigation encompassed major producing zones spanning the North, Northeast, Midwest, Southeast, and South of Brazil, along with the aforementioned countries. A conducive environment for this crop's growth features air temperatures between 21 to 25 °C and a minimum precipitation of 1200 mm per cycle. We sourced the current climate data from the WorldClim version 2 platform. Meanwhile, projections for future climatic parameters were derived from WorldClim 2.1, utilizing the IPSL-CM6A-LR model with a refined 30-s spatial resolution. We took into account four distinct socio-economic pathways over varying timelines: 2021-2040, 2041-2060, 2061-2081, and 2081-2100. Geographic information system data aided in the spatial interpolation across Brazil, applying the Kriging technique. The outcomes revealed a majority of the examined areas as non-conducive for yerba mate cultivation, with a scanty 12.25% (1.5 million km2) deemed favorable. Predominantly, these propitious regions lie in southern Brazil and Uruguay, the present-day primary producers of yerba mate. Alarming was the discovery that forthcoming climatic scenarios predominantly forecast detrimental shifts, characterized by escalating average air temperatures and diminishing rainfall. These trends portend a decline in suitable cultivation regions for yerba mate.


Assuntos
Mudança Climática , Ilex paraguariensis , Ilex paraguariensis/crescimento & desenvolvimento , Modelos Teóricos , Temperatura , Previsões , América do Sul
14.
PeerJ ; 12: e16772, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38525284

RESUMO

Background: Semiaquatic bugs (Hemiptera: Heteroptera: Gerromorpha) are distributed worldwide and play fundamental roles in limnic ecosystems. They are the most successful group of organisms to occupy the air-water interface, are important models to study ecology and evolution, and can be relevant tools in biomonitoring. Veliidae is the second most speciose family of semiaquatic bugs, but its internal classification, including subfamilies and genera, is artificial and based on symplesiomorphies. One of these non-monophyletic entities is Paravelia Breddin, 1898, the largest genus in the subfamily Veliinae. Results: In an effort to better classify the Veliinae, we describe Foveavelia to hold five South American species previously placed in Paravelia. The new genus is characterized by the following combination of features: unusual coarse cuticular punctures throughout the thorax and abdomen; a pair of small, frosty, pubescent areas formed by a very dense layer of short setae on the anterior lobe of the pronotum; fore tibial grasping comb present only in males; middle tibia with a row of elongate dark-brown trichobothria-like setae on the distal third, decreasing in size distally; macropterous specimens with the apical macula of the forewings elongate and constricted at mid-length, reaching the wing apex; and the male proctiger with a pair of anterodorsal projections. Besides the description, a key to the species of Foveavelia is provided, accompanied by illustrations and a species distribution map.


Assuntos
Heterópteros , Animais , Masculino , Ecossistema , Ecologia , Monitoramento Biológico , América do Sul
15.
Sci Rep ; 14(1): 2972, 2024 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-38453955

RESUMO

Humans have a long history of transporting and trading plants, contributing to the evolution of domesticated plants. Theobroma cacao originated in the Neotropics from South America. However, little is known about its domestication and use in these regions. In this study, ceramic residues from a large sample of pre-Columbian cultures from South and Central America were analyzed using archaeogenomic and biochemical approaches. Here we show, for the first time, the widespread use of cacao in South America out of its native Amazonian area of origin, extending back 5000 years, likely supported by cultural interactions between the Amazon and the Pacific coast. We observed that strong genetic mixing between geographically distant cacao populations occurred as early as the middle Holocene, in South America, driven by humans, favoring the adaptation of T. cacao to new environments. This complex history of cacao domestication is the basis of today's cacao tree populations and its knowledge can help us better manage their genetic resources.


Assuntos
Cacau , Domesticação , Humanos , Cacau/genética , América do Sul , América Central
16.
PLoS One ; 19(3): e0298896, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38507346

RESUMO

Starch residue analysis was carried out on stone tools recovered from the bottom layer of the Anakena site on Rapa Nui (Easter Island). These deposits have been dated to AD 1000-1300 AD and so far, represent the earliest evidence of human settlement on this island. Twenty obsidian tools were analyzed. Analysis of 46 starch grains recovered from 20 obsidian tools from the earliest dated level of the Anakena site on Rapa Nui provides direct evidence for translocation of traditional crop plants at initial stages of the colonization of this island. The analysis of starch grains was based mainly on statistical methods for species identification but was complemented by visual inspection in some cases. Our results identify taxons previously unknown to have been cultivated on the island, such as breadfruit (Artocarpus altilis), Zingiber officinale (ginger), and starch grains of the Spondias dulcis and Inocarpus fagifer tropical trees. Additionally, starch grains of Colocasia esculenta (taro) and Dioscorea sp. (yam), both common species in Pacific agriculture, were identified. Furthermore, the presence of four American taxa Ipomoea batatas (sweet potato), Canna sp. (achira), Manihot esculenta (manioc), and Xanthosoma sp., was detected. The occurrence of Canna sp., M. esculenta, and Xanthosoma sp. starch grains suggests the translocation of previously not described South American cultivars into the Pacific. The detection of I. batatas from this site in Rapa Nui constitutes the earliest record of this cultigen in the Pacific. Our study provides direct evidence for translocation of a set of traditional Polynesian and South American crop plants at the initial stages of colonization in Rapa Nui.


Assuntos
Artocarpus , Dioscorea , Ipomoea batatas , Humanos , Amido , Grupos Raciais , Produtos Agrícolas , América do Sul
17.
Microbiol Res ; 283: 127650, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38452553

RESUMO

Azospirillum sp. is a plant growth-promoting rhizobacteria largely recognized for its potential to increase the yield of different important crops. In this work, we present a thorough genomic and phenotypic analysis of A. argentinense Az39T to provide new insights into the beneficial mechanisms of this microorganism. Phenotypic analyses revealed the following in vitro abilities: growth at 20-38 °C (optimum, 28 °C), pH 6.0-8.0 (optimum, pH 6.8), and in the presence of 1% (w/v) NaCl; production of variable amounts of PHB as intracellular granules; nitrogen fixation under microaerophilic conditions; IAA synthesis in the presence of L-tryptophan. Through biochemical (API 20NE) and carbon utilization profiling (Biolog) assays, we proved that A. argentinense Az39T is able to use 15 substrates and metabolize 19 different carbon substrates. Lipid composition indicated a predominance of medium and long-chain saturated fatty acids. A total of 6 replicons classified as one main chromosome, three chromids, and two plasmids, according to their tRNA and core essential genes contents, were identified. Az39T genome includes genes associated with multiple plant growth-promoting (PGP) traits such as nitrogen fixation and production of auxins, cytokinin, abscisic acid, ethylene, and polyamines. In addition, Az39T genome harbor genetic elements associated with physiological features that facilitate its survival in the soil and competence for rhizospheric colonization; this includes motility, secretion system, and quorum sensing genetic determinants. A metadata analysis of Az39T agronomic performance in the pampas region, Argentina, demonstrated significant grain yield increases in wheat and maize, proving its potential to provide better growth conditions for dryland cereals. In conclusion, our data provide a detailed insight into the metabolic profile of A. argentinense Az39T, the strain most widely used to formulate non-legume inoculants in Argentina, and allow a better understanding of the mechanisms behind its field performance.


Assuntos
Azospirillum , Azospirillum/fisiologia , Ácidos Indolacéticos/metabolismo , Desenvolvimento Vegetal , Carbono , América do Sul
18.
Parasitol Res ; 123(3): 151, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38441704

RESUMO

Culicids in Argentinean Patagonia are characterized by low species diversity and adaptation to extreme environmental conditions, yet few studies have been conducted in the region. To further assess the occurrence of Culicidae in Western Patagonia, and in particular the presence of Culex pipiens bioforms at the southernmost extent of their distribution, immature and adult specimens were collected aboveground across various land uses located in shrubland, steppe, and deciduous forest between 38.96 and 46.55°S. Mosquitoes were reported at 35 of the 105 inspected sites. Five species from the genus Culex were identified, all of which were present in the steppe and the forest, while only Cx. apicinus and members of the Cx. pipiens complex were collected in the shrubland. Within the latter, a total of 150 specimens were molecularly identified by PCR amplification of Ace-2 and CQ11 loci. The first-to-date occurrence of bioform pipiens in South America is reported, along with the first records of Cx. quinquefasciatus signatures in Patagonia. In addition, the distribution of Cx. acharistus and Cx. dolosus as south as Santa Cruz province is expanded, and the first record of Cx. eduardoi in Río Negro province is provided. Immature specimens of Cx. pipiens were conspicuous in human-made aquatic habitats (both containers and in the ground), while Cx. acharistus was more prominent in artificial containers and Cx. eduardoi was mainly in ground habitats, either natural or human-made. These findings provide valuable insights into the distribution and ecological roles of these mosquito species in a region of extreme environmental conditions.


Assuntos
Culex , Culicidae , Adulto , Humanos , Animais , América do Sul
19.
Evolution ; 78(5): 1018-1019, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38465471

RESUMO

Recent perspectives on speciation genomics emphasize the pivotal role of hybridization in driving rapid radiations. The Liolaemus lizard genus displays impressive species richness with around 290 species widely distributed across southern South America. Sánchez et al. conducted a comprehensive study on the 5-million-year-old Liolaemus kingii group, which includes 14 species. The research provides new key insights to enhance our understanding of this rapid radiation, including its diversification in space and time and the consequences of hybridization in its morphological evolution and taxonomy.


Assuntos
Especiação Genética , Hibridização Genética , Lagartos , Animais , Lagartos/genética , Lagartos/classificação , América do Sul
20.
Environ Pollut ; 347: 123772, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38490527

RESUMO

Determining the sources of marine litter is necessary to mitigate this increasing global problem. Plastic bottles are useful tracers of marine litter and constitute the main item (24%) stranding on remote beaches in the Galapagos Islands. The aim of this study was to estimate the abundance of plastic bottles in remote beaches and inferred their sources. To do so, we collected plastic bottles at 60 remote Galapagos Island beaches from 2018 to 2022. 76% of beaches were qualified as badly polluted, with >34 bottles·100 m-1. Most identified bottles came from Peru (71%), followed by China (17%) and Ecuador (9%). Although most locally-sold products are made in Ecuador, they contribute little to beach litter loads. Polyethylene terephthalate bottles with lid (necessary for litter dispersal) represented 88% of all bottles, demonstrating that most of the litter reaching the Galapagos comes from distant sources, mainly from South America. However, bottle ages indicate that at least 10% of Peruvian, 26% of Ecuadorian, and all Chinese bottles likely were dumped from ships. Reducing marine litter reaching the Galapagos Islands requires tackling litter leakage from land-based sources in South America and better compliance with regulations banning the dumping of plastics and other persistent wastes from ships.


Assuntos
Praias , Resíduos , Equador , Resíduos/análise , Monitoramento Ambiental , América do Sul , Plásticos
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