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1.
Phytopathology ; 110(7): 1342-1351, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32490753

RESUMO

In Colombia, late blight is considered one of the most limiting diseases on potato and tomato production. Recently, a new Phytophthora species, P. betacei, was described infecting tree tomato crops in the south of Colombia. However, the distribution and the host range of this new emerging pathogen in the country are unknown. The main aims of this study were to determine if this novel species is confined to the south of Colombia, to assess if P. betacei represents a genetically uniform clone across Colombia and to determine if in all regions there is a clear differentiation between the two Phytophthora species. Therefore, we characterized Phytophthora isolates obtained from tree tomato and potato crops in a central region of Colombia and compared them with the strains from the south. Initially, we evaluated the genetic differentiation among Phytophthora strains obtained from tree tomato and potato crops using simple sequence repeat markers. Results showed a strong population structure between P. infestans and P. betacei. However, we did not detect any genetic differentiation within P. infestans or P. betacei populations from different regions. Furthermore, we detected significant morphological differences among the species based on growth and sporangial morphology measurements. We also showed that strains of Phytophthora spp. are predominantly of the A1 mating type and belong to EC-1 and EC-3 clonal lineages for P. infestans and P. betacei, respectively. Our results describe the expanded geographical range of the new species of P. betacei in the central region of Colombia.


Assuntos
Phytophthora infestans/genética , Solanum tuberosum , Colômbia , Repetições de Microssatélites , Doenças das Plantas
2.
J Anim Ecol ; 89(8): 1754-1765, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32198927

RESUMO

Traditionally, most studies have described the organization of host-parasite interaction networks by considering only few host groups at limited geographical extents. However, host-parasite relationships are merged within different taxonomic groups and factors shaping these interactions likely differ between host and parasite groups, making group-level differences important to better understand the ecological and evolutionary dynamics of these interactive communities. Here we used a dataset of 629 ectoparasite species and 251 species of terrestrial mammals, comprising 10 orders distributed across the Nearctic and Neotropical regions of Mexico to assess the species-level drivers of mammalian ectoparasite faunas. Specifically, we evaluated whether body weight, geographical range size and within-range mammal species richness (i.e. diversity field) predict mammal ectoparasite species richness (i.e. degree centrality) and their closeness centrality within the mammal-ectoparasite network. In addition, we also tested if the observed patterns differ among mammal orders and if taxonomic closely related host mammals could more likely share the same set of ectoparasites. We found that ectoparasite species richness of small mammals (mainly rodents) with large proportional range sizes was high compared to large-bodied mammals, whereas the diversity field of mammals had no predictive value (except for bats). We also observed that taxonomic proximity was a main determinant of the probability to share ectoparasite species. Specifically, the probability to share ectoparasites in congeneric species reached up to 90% and decreased exponentially as the taxonomic distance increased. Further, we also detected that some ectoparasites are generalists and capable to infect mammalian species across different orders and that rodents have a remarkable role in the network structure, being closely connected to many other taxa. Hence, because many rodent species have synanthropic habits they could act as undesired reservoirs of disease agents for humans and urban animals. Considering the reported worldwide phenomenon of the proliferation of rodents accompanying the demographic decrease or even local extinction of large-bodied mammal species, these organisms may already be an increasing health threat in many regions of the world.


Assuntos
Ectoparasitoses , Parasitos , Doenças dos Roedores , Animais , Ectoparasitoses/veterinária , Interações Hospedeiro-Parasita , Mamíferos , México , Doenças dos Roedores/epidemiologia , Roedores
3.
Ticks Tick Borne Dis ; 9(5): 1264-1274, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29773336

RESUMO

The aim of this work was to generate knowledge on ecological aspects of Amblyomma sculptum in Argentina, such as seasonal dynamics, geographical range size, hosts, genetic diversity and phylogeography. Adult and immature A. sculptum ticks were collected in different localities of Argentina to know the geographical range size and hosts. The genetic diversity of this tick was studied through analyses of 16S rDNA sequences. To describe the seasonal dynamics, free-living ticks were monthly collected from October 2013 to October 2015. A. sculptum shows a marked ecological preference for Chaco Húmedo eco-region and "Albardones" forest of the great rivers in the wetlands in the Chaco Biogeographical Province, and for Selvas Pedemontanas and Selva Montana in the Yungas Biogeographical Province. This species has low host specificity, and it has large wild and domestic mammals as principal hosts to both immature and adult stages. Amblyomma sculptum is characterized by a one-year life cycle. Larvae peak in early winter, nymphs peaked during mid-spring, and adults during late summer and mid-summer. The genetic divergence was low and the total genetic variability was attributable to differences among populations. This fact could be associated to stochastics process linked to micro-habitat variations that could produce a partial restriction to gene flow among populations. The geographic regions do not contribute much to explain the A. sculptum population genetic structure, with an ancestral haplotype present in most populations, which gives rise to the rest of the haplotypes denoting a rapid population expansion.


Assuntos
Variação Genética , Ixodidae/genética , Ixodidae/fisiologia , Estações do Ano , Infestações por Carrapato/epidemiologia , Animais , Animais Domésticos/parasitologia , Argentina/epidemiologia , Ecossistema , Haplótipos , Especificidade de Hospedeiro , Larva/genética , Larva/fisiologia , Mamíferos/parasitologia , Ninfa/genética , Ninfa/fisiologia , Filogenia , Filogeografia , RNA Ribossômico 16S/genética
4.
Ecology ; 99(2): 499, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29341115

RESUMO

The data set represents the first attempt at a large-scale inventory of non-volant mammals, with potential applications to performing macroecological studies, developing conservation strategies, and undertaking population and community ecology research, but also to evaluate the ecological consequences of fragmentation and defaunation. Our objectives for compiling these data were to summarize information about inventories of non-volant mammals in the critically important area of the Upper Paraná River Basin by focusing on species richness and index of frequency of occurrence and to identify gaps in knowledge regarding non-volant mammal communities in order to guide future sampling efforts. The data set comprises studies on communities of non-volant mammals from 52 locations covering more than 1,000 km2 and comprises portion of four Brazilian states in the Upper Paraná River Basin. We listed 81 species of non-volant mammals distributed among 58 genera, 22 families, and 9 orders. Rodentia (28 species) was the richest order, followed by Carnivora (17 spp.) and Didelphimorphia (15 spp.). The richest family was Cricetidae (20 spp.), followed by Didelphidae (15 spp.), and Dasypodidae and Felidae (six spp.). Considering national conservation status, one species are considered endangered and 16 vulnerable. Considering global conservation status, 7 species are considered vulnerable, 10 are considered near threatened, and 6 are data deficient. According to the index of frequency of occurrence, Myrmecophaga tridactyla was the most frequent species, occurring at 88.64% of all sites, while 25 species were considered very restricted, occurring in just 2.56% of all sites. In general, the non-volant mammal fauna was composed of mainly very restricted (VR, 25 species) and localized species (L, 25 species), which account for 61.7% of the known species, while 38.3% are restricted (R, 8 species), common (C, 16 species), and widespread (W, 7 species). Seven marsupials and five small rodents had their distributions extended in the central-south of Brazil. All of these species are considered data deficient or threatened, which highlights the importance of these records. No copyright restrictions are associated with the use of this data set. Please cite this data paper when the data are used in publications. We also request that researchers and teachers inform us of how they are using the data.

5.
Conserv Biol ; 28(5): 1260-70, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25065287

RESUMO

We aspired to set conservation priorities in ways that lead to direct conservation actions. Very large-scale strategic mapping leads to familiar conservation priorities exemplified by biodiversity hotspots. In contrast, tactical conservation actions unfold on much smaller geographical extents and they need to reflect the habitat loss and fragmentation that have sharply restricted where species now live. Our aspirations for direct, practical actions were demanding. First, we identified the global, strategic conservation priorities and then downscaled to practical local actions within the selected priorities. In doing this, we recognized the limitations of incomplete information. We started such a process in Colombia and used the results presented here to implement reforestation of degraded land to prevent the isolation of a large area of cloud forest. We used existing range maps of 171 bird species to identify priority conservation areas that would conserve the greatest number of species at risk in Colombia. By at risk species, we mean those that are endemic and have small ranges. The Western Andes had the highest concentrations of such species-100 in total-but the lowest densities of national parks. We then adjusted the priorities for this region by refining these species ranges by selecting only areas of suitable elevation and remaining habitat. The estimated ranges of these species shrank by 18-100% after accounting for habitat and suitable elevation. Setting conservation priorities on the basis of currently available range maps excluded priority areas in the Western Andes and, by extension, likely elsewhere and for other taxa. By incorporating detailed maps of remaining natural habitats, we made practical recommendations for conservation actions. One recommendation was to restore forest connections to a patch of cloud forest about to become isolated from the main Andes.


Assuntos
Biodiversidade , Aves/fisiologia , Conservação dos Recursos Naturais/métodos , Ecossistema , Distribuição Animal , Animais , Colômbia , Mapeamento Geográfico
6.
Ann Bot ; 113(2): 251-66, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24252281

RESUMO

BACKGROUND AND AIMS: The underlying evolutionary processes of pollinator-driven floral diversification are still poorly understood. According to the Grant-Stebbins model speciation begins with adaptive local differentiation in the response to spatial heterogeneity in pollinators. Although this crucial process links the micro- and macroevolution of floral adaptation, it has received little attention. In this study geographical phenotypic variation was investigated in Patagonian Calceolaria polyrhiza and its pollinators, two oil-collecting bee species that differ in body size and geographical distribution. METHODS: Patterns of phenotypic variation were examined together with their relationships with pollinators and abiotic factors. Six floral and seven vegetative traits were measured in 45 populations distributed across the entire species range. Climatic and edaphic parameters were determined for 25 selected sites, 2-16 bees per site of the most frequent pollinator species were captured, and a critical flower-bee mechanical fitting trait involved in effective pollination was measured. Geographical patterns of phenotypic and environmental variation were examined using uni- and multivariate analyses. Decoupled geographical variation between corolla area and floral traits related to the mechanical fit of pollinators was explored using a Mantel test. KEY RESULTS: The body length of pollinators and the floral traits related to mechanical fit were strongly correlated with each other. Geographical variation of the mechanical-fit-related traits was decoupled from variation in corolla size; the latter had a geographical pattern consistent with that of the vegetative traits and was mainly affected by climatic gradients. CONCLUSIONS: The results are consistent with pollinators playing a key role in shaping floral phenotype at a geographical scale and promoting the differentiation of two floral ecotypes. The relationship between the critical floral-fit-related trait and bee length remained significant even in models that included various environmental variables and an allometric predictor (corolla area). The abiotic environment also has an important role, mainly affecting floral size. Decoupled geographical variation between floral mechanical-fit-related traits and floral size would represent a strategy to maintain plant-pollinator phenotypic matching in this environmentally heterogeneous area.


Assuntos
Abelhas/fisiologia , Flores/anatomia & histologia , Geografia , Óleos de Plantas/metabolismo , Característica Quantitativa Herdável , Scrophulariaceae/anatomia & histologia , Scrophulariaceae/fisiologia , Animais , Argentina , Clima , Flores/fisiologia , Análise Multivariada , Fenótipo , Polinização , Análise de Regressão
7.
Ecol Lett ; 16(12): 1446-54, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24119177

RESUMO

Despite being a fundamental aspect of biodiversity, little is known about what controls species range sizes. This is especially the case for hyperdiverse organisms such as plants. We use the largest botanical data set assembled to date to quantify geographical variation in range size for ~ 85 000 plant species across the New World. We assess prominent hypothesised range-size controls, finding that plant range sizes are codetermined by habitat area and long- and short-term climate stability. Strong short- and long-term climate instability in large parts of North America, including past glaciations, are associated with broad-ranged species. In contrast, small habitat areas and a stable climate characterise areas with high concentrations of small-ranged species in the Andes, Central America and the Brazilian Atlantic Rainforest region. The joint roles of area and climate stability strengthen concerns over the potential effects of future climate change and habitat loss on biodiversity.


Assuntos
Biodiversidade , Clima , Ecossistema , Plantas/classificação , América Central , Conservação dos Recursos Naturais , Geografia , Modelos Teóricos , América do Norte , América do Sul , Análise Espacial
8.
Chiropt. Neotrop. (Impr.) ; 12(2): 280-285, 2006.
Artigo em Português | LILACS-Express | VETINDEX | ID: biblio-1471799

RESUMO

Herein we report two new occurrences of phyllostomids bats (Mesophylla macconnelli and Artibeus concolor) in the savanna habit (cerrado) in west-central Brazil. Mesophylla macconnelli was collected in the protected area of a private natural heritage reserve (Reserva Particular do Patrimônio Natural Pousada das Araras), in Serranópolis municipality, Goiás state. Artibeus concolor was trapped near Serra da Mesa reservoir, in Niquelândiamunicipality, Goiás state. These records enlarge considerably the south distribution of the two species.


Herein we report two new occurrences of phyllostomids bats (Mesophylla macconnelli and Artibeus concolor) in the savanna habit (cerrado) in west-central Brazil. Mesophylla macconnelli was collected in the protected area of a private natural heritage reserve (Reserva Particular do Patrimônio Natural Pousada das Araras), in Serranópolis municipality, Goiás state. Artibeus concolor was trapped near Serra da Mesa reservoir, in Niquelândia municipality, Goiás state. These records enlarge considerably the south distribution of the two species.

9.
Chiropt. neotrop. ; 12(2): 280-285, 2006.
Artigo em Português | VETINDEX | ID: vti-464692

RESUMO

Herein we report two new occurrences of phyllostomids bats (Mesophylla macconnelli and Artibeus concolor) in the savanna habit (cerrado) in west-central Brazil. Mesophylla macconnelli was collected in the protected area of a private natural heritage reserve (Reserva Particular do Patrimônio Natural Pousada das Araras), in Serranópolis municipality, Goiás state. Artibeus concolor was trapped near Serra da Mesa reservoir, in Niquelândiamunicipality, Goiás state. These records enlarge considerably the south distribution of the two species.


Herein we report two new occurrences of phyllostomids bats (Mesophylla macconnelli and Artibeus concolor) in the savanna habit (cerrado) in west-central Brazil. Mesophylla macconnelli was collected in the protected area of a private natural heritage reserve (Reserva Particular do Patrimônio Natural Pousada das Araras), in Serranópolis municipality, Goiás state. Artibeus concolor was trapped near Serra da Mesa reservoir, in Niquelândia municipality, Goiás state. These records enlarge considerably the south distribution of the two species.

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