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A survey of the in vitro antifungal activity of heather (Erica sp.) organic honey

Feás, Xesús; Estevinho, Leticia M.
Fonte: Mary Ann Liebert Publicador: Mary Ann Liebert
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
46.04%
Monofloral heather (Erica sp.) honey samples (n = 89), harvested in Portugal according to European organic beekeeping rules, were analyzed to test their antifungal effect against Candida albicans, Candida krusei, and Cryptococcus neoformans. A synthetic honey solution was also tested to determine antifungal activity attributable to sugars. The specific growth rate (l) values showed that growth of all the yeasts was reduced in the presence of honey. The honey concentration (% wt/vol) that inhibited 10% of the yeast growth (Xmin) was 13.5% for C. albicans, 20.5% for C. krusei, and 17.1% for C. neoformans. The respective concentrations of heather honey and synthetic honey in the C. krusei culture medium above 60% (wt/vol) that inhibited 90% of the yeast growth (Xmax) and Xmin, respectively, were established, whereas C. albicans and C. neoformans were more resistant because Xmax values were not reached over the range tested (10–60%, wt/vol). Heather honey might be tapped as a natural resource to look for new medicines for the treatment of mycotic infections. Further studies are now required to demonstrate if this antifungal activity has any clinical application.

Mapping five repetitive DNA classes in sympatric species of Hypostomus (Teleostei: Siluriformes: Loricariidae): analysis of chromosomal variability

Pansonato-Alves, José Carlos; Serrano, Érica Alves; Utsunomia, Ricardo; Scacchetti, Priscilla Cardim; Oliveira, Claudio; Foresti, Fausto
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 1-13
ENG
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Fish belonging to the genus Hypostomus are known for exhibiting a striking diversity in its karyotype structure, however the knowledge concerning the distribution patterns of heterochromatin and location of repetitive DNA sequences in the karyotypes is still limited. Aiming a better understanding of the chromosomal organization in this group, we analyzed three sympatric species of Hypostomus collected in the Hortelã stream, a component of the Paranapanema River basin, Botucatu/SP/Brazil. The analyses involved the cytogenetic characterization and chromosomal mapping of repetitive sequences and intra/interspecific comparisons using sequences of the cytochrome C oxidase subunit I. The results revealed that H. ancistroides presents a karyotype with 2n = 68 chromosomes, H. strigaticeps 2n = 72 chromosomes, and H. nigromaculatus 2n = 76 chromosomes. In addition to differences found in the diploid number, it was also observed variations in karyotypic formulae, amount of constitutive heterochromatin, and location of nucleolus organizer regions. The cytogenetic mapping of 5S and 18S rDNA, as well as of the H3 histone gene, disclosed a differential dispersion process among the three species. In some cases the Rex1 transposable element showed to be co-located with 5S rDNA sites. The molecular analyses support the cytogenetic data and represent an additional tool for the characterization of the analyzed species. The results evidenced that chromosomal variations are not restricted to differences in diploid number or karyotypic macrostructure in the genus Hypostomus...

Ecology and evolution of the arborescent Erica azorica Hochst (Ericaceae)

Ribeiro, Sérvio P.; Borges, Paulo A. V.; Gaspar, Clara
Fonte: Universidade dos Açores Publicador: Universidade dos Açores
Tipo: Artigo de Revista Científica
Publicado em //2003 ENG
Relevância na Pesquisa
36.27%
Copyright © 2003 Universidade dos Açores.; O objectivo do presente estudo consistiu em avaliar o impacto da herbivoria por insectos na arquitectura da urze Erica azorica Hochst, planta endémica da Laurisilva dos Açores. Erica azorica é uma planta com porte arbustivo e pioneira que consegue persistir nas florestas maduras de Laurisilva, onde pode atingir porte arbóreo tornando-se emergente no copado. Testa-se a hipótese de que a arquitectura da planta pode ser modificada através do dano provocado por insectos dando-se esta alteração através do decréscimo do número de ramificações no botão terminal, alteração do comprimento dos ramos terminais de um módulo, e consequentemente alteração da estrutura do módulo. Fez-se uma amostragem em 1999 (Agosto - Setembro) e 2000 (Julho) de três populações distintas na ilha do Pico: "Manhenha", população pioneira; 'Caiado', população em pastagem abandonada nas margens da Lagoa do Caiado; e "Mistério da Prainha - Chão Verde", uma população emergente, com árvores de 8 a 11 metros de altura numa floresta madura localizada numa corrente de lava recente. Foram amostradas ao acaso um total de 10 plantas por população, tendo-se colhido 10 módulos de ramos a diferentes alturas e posições dentro de cada planta. Em cada módulo contou-se o número de ramificações...

Potential use of Erica andevalensis and Erica australis in phytoremediation of sulphide mine environments: São Domingos, Portugal

Abreu, M.M.; Tavares, M.T.; Batista, M.J.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Publicado em //2008 ENG
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The area around the São Domingos copper mine (Iberian Pyrite Belt) is subject of great environmental concern as acid mine water occurs several kilometres downstream of the mine. In addition thousands of tons of mine waste are present. Erica australis and Erica andevalensis, which are two spontaneous plant species of this area, have been studied with regard to their potential for phytostabilization. Soils and plants from São Domingos and from a reference site (Moreanes) were analysed for soil characteristics, chemical element content in soils (total and AB-DTPA bioavailable fraction) and in plants. Superficial and seepage water as well as waste material leachates were also analysed. Seepage water showed high redox potential (mean 481 mV), high conductivity (mean 4337 μS cm−1) and low pH values (mean 2.6), being classified as mining water. Leachate solutions possessed mainly high levels of Fe, Al and SO42−. Soils in the mining area were highly contaminated in Pb, As and Sb. Locally also high values of Cu and Zn were encountered and the soil available fraction of the majority of the elements showed also quite high values. E. andevalensis grows in soils with pH between 3 and 4, whereas E. australis was only found in soils with pH above 3.5. Both species grow spontaneously in soils...

Seasonal fluctuation in the population of Harmonia axyridis (Pallas, 1773) (Coleoptera: Coccinellidae) and co-occurrence with other Coccinellids in the Federal District of Brazil

Harterreiten-Souza,Érica Sevilha; Togni,Pedro Henrique Brum; Milane,Paloma Virgínia Gambarra Nitão; Cavalcante,Kelly Ramalho; Medeiros,Maria Alice de; Pires,Carmen Silvia Soares; Sujii,Edison Ryoiti
Fonte: Museu de Zoologia da Universidade de São Paulo Publicador: Museu de Zoologia da Universidade de São Paulo
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2012 EN
Relevância na Pesquisa
35.99%
The multicolored Asian lady beetle, Harmonia axyridis (Pallas, 1773), was first recorded in Brazil in 2002 in Paraná state and subsequently observed in Santa Catarina, Rio Grande do Sul and Minas Gerais. This species can spread to new areas and become dominant in the local community, reducing the density and diversity of native species, mainly Coccinellidae. The objective of this work was to record for the first time the occurrence of H. axyridis in the Federal District and its co-occurrence with other Coccinellidae species. The individuals were collected directly from plants at an organic farm in Taguatinga and in experimental fields of Embrapa Hortaliças, located in the Federal District, from August 2008 to January 2010. We collected 881 Coccinelids, and of these, 110 belong to the species H. axyridis. These were found exclusively on the following plants of the succinea group: maize, cabbage, cauliflower, broccoli, kale, cucumber, cotton, tomato and coriander. We also observed its co-occurrence with the following lady beetle species: Cycloneda sanguine (Linnaeus, 1763), Hippodamia convergens (Guerin-Meneville 1842), Eriopis connexa (German, 1824), Scymnus sp., Nephaspis sp., Azya luteipes (Mulsant, 1850), Hyperaspis festiva (Mulsant...

Phylogenetic relationships in the Drosophila fasciola species subgroup (Diptera, Drosophilidae) inferred from partial sequences of the mitochondrial cytochrome oxidase subunit I (COI) gene

Silva-Bernardi,Erica C.C.; Morales,Adriana C.; Sene,Fabio M.; Manfrin,Maura H.
Fonte: Sociedade Brasileira de Genética Publicador: Sociedade Brasileira de Genética
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2006 EN
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35.96%
The repleta group is one of the largest and most complex species groups in the genus Drosophila, representing an important biological model for the elaboration of evolutionary and biogeographical hypotheses on the American Continent. It is divided into six subgroups, of which the fasciola subgroup is the only one with most of its species found in the humid forests of Central and South America. With the aim of understanding the origin and evolution of the fasciola subgroup, and consequently adding information about the repleta group, we analyzed partial sequences of the mitochondrial cytochrome oxidase subunit I (COI) gene of nine Drosophila species (D. carolinae, D. coroica, D. ellisoni, D. fascioloides, D. ivai, D. moju, D. onca, D. rosinae and D. senei). The phylogenetic hypotheses obtained neither defined the relationships between the subgroups of the repleta group nor defined all the interspecific relationships in the fasciola subgroup. We found that the species D. carolinae, D. coroica, D. onca, D. rosinae and D. senei comprised a clade in which D. carolinae, D. onca and D. senei appeared together at a polytomy while D. fascioloides and D. ellisoni comprised another clade with a high bootstrap value.

The Plant Pathogen Phytophthora andina Emerged via Hybridization of an Unknown Phytophthora Species and the Irish Potato Famine Pathogen, P. infestans

Goss, Erica M.; Cardenas, Martha E.; Myers, Kevin; Forbes, Gregory A.; Fry, William E.; Restrepo, Silvia; Grünwald, Niklaus J.
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 16/09/2011 EN
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Emerging plant pathogens have largely been a consequence of the movement of pathogens to new geographic regions. Another documented mechanism for the emergence of plant pathogens is hybridization between individuals of different species or subspecies, which may allow rapid evolution and adaptation to new hosts or environments. Hybrid plant pathogens have traditionally been difficult to detect or confirm, but the increasing ease of cloning and sequencing PCR products now makes the identification of species that consistently have genes or alleles with phylogenetically divergent origins relatively straightforward. We investigated the genetic origin of Phytophthora andina, an increasingly common pathogen of Andean crops Solanum betaceum, S. muricatum, S. quitoense, and several wild Solanum spp. It has been hypothesized that P. andina is a hybrid between the potato late blight pathogen P. infestans and another Phytophthora species. We tested this hypothesis by cloning four nuclear loci to obtain haplotypes and using these loci to infer the phylogenetic relationships of P. andina to P. infestans and other related species. Sequencing of cloned PCR products in every case revealed two distinct haplotypes for each locus in P. andina, such that each isolate had one allele derived from a P. infestans parent and a second divergent allele derived from an unknown species that is closely related but distinct from P. infestans...

Bothaella manhi, a new species of tribe Aedini (Diptera: Culicidae) from the Cuc Phuong National Park of Vietnam based on morphology and DNA sequence

COOK, SHELLEY; LIEN, NGO GIANG; MCALISTER, ERICA; HARBACH, RALPH E.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em 29/10/2010 EN
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A new species of genus Bothaella (Diptera: Culicidae) collected along with two other species of the genus during surveys for flavivirus isolations in the Cuc Phuong National Park in northern Vietnam is formally described and named as Bothaella manhi, sp. n. The adults, pupa and fourth-instar larva are characterized, the male genitalia and the two immature stages are illustrated and DNA sequence data are included for regions coding for sections of the COI and COII genes (mtDNA). The species is compared and distinguished from the other species of the genus, and sequence data are used to hypothesise its phylogenetic relationship with Bo. helenae and Bo. kleini, the other two species collected during the survey.

High Degree of Transferability of 86 Newly Developed Zebra Finch EST-Linked Microsatellite Markers in 8 Bird Species

Karaiskou, Nikoletta; Buggiotti, Laura; Leder, Erica; Primmer, Craig R.
Fonte: Oxford University Press Publicador: Oxford University Press
Tipo: Artigo de Revista Científica Formato: text/html
EN
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High-resolution analysis for population genetic and functional studies requires the use of large numbers of polymorphic markers. The recent increase of available genetic tools is facilitated by the use of publicly available expressed sequence tag (EST) sequence databases that are a valuable resource for identifying gene-linked markers. In the present study, we applied bioinformatics analyses to identify microsatellite markers present in EST sequences from a zebra finch (Taeniopgia guttata) EST database and we explore the success of cross-species amplification of EST-linked microsatellite markers in 7 passerine and 1 nonpasserine species. Eighty-six zebra finch EST-linked microsatellite loci were screened for polymorphism revealing a high amplification success rate and adequate levels of polymorphism (33.3–51%) for relatively closely related species, whereas success decreased in the most distantly related species to zebra finch. EST-linked microsatellites appear to be more highly transferable between taxa than anonymous microsatellites as they revealed higher amplification and polymorphism success between different families indicating that they will be a useful source of gene-linked polymorphic markers in a broad range of avian species.

Frugivores at higher risk of extinction are the key elements of a mutualistic network

Vidal, Mariana M.; Hasui, Erica; Pizo, Marco A.; Tamashiro, Jorge Y.; Silva, Wesley R.; Guimaraes, Paulo R.
Fonte: Ecological Soc Amer Publicador: Ecological Soc Amer
Tipo: Artigo de Revista Científica Formato: 3440-3447
ENG
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq); Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Processo FAPESP: 2010/11633-6; Processo FAPESP: 2009/54422-8; Most tree species rely on vertebrates for seed dispersal, and many vertebrates use fruits as food resources in tropical forests. Therefore, plant-frugivore interactions affect population dynamics and persistence in ecological communities. Plant-frugivore interactions often involve many species, forming networks of interacting plants and animals that play different roles in determining network organization. The network organization is the way interactions are structured in the community, which may have consequences for its ecological and evolutionary dynamics. Some species have greater influences on network organization and may be particularly important to species persistence. We identified the frugivores most important to the organization of networks of plants and frugivorous birds in three contiguous Atlantic forest sites in southeastern Brazil. We found that the species that contributed most to network organization were at higher risk of extinction. Among the main contributors to network organization were two cotingas and a toucan...

Resource partitioning and ecomorphological variation in two syntopic species of Lebiasinidae (Characiformes) in an Amazonian stream

SILVA,Nathália Carina dos Santos; COSTA,Aluízio José Lopes da; LOUVISE,José; SOARES,Bruno Eleres; REIS,Vanessa Cristine e Souza; ALBRECHT,Míriam Pilz; CARAMASCHI,Érica Pellegrini
Fonte: Instituto Nacional de Pesquisas da Amazônia Publicador: Instituto Nacional de Pesquisas da Amazônia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2016 EN
Relevância na Pesquisa
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ABSTRACTResource partitioning is important for species coexistence. Species with similar ecomorphology are potential competitors, especially when phylogenetically close, due to niche conservatism. The aim of this study was to investigate the resource partitioning among populations of two species of lebiasinids (Copella nigrofasciata and Pyrrhulina aff. brevis) that co-occur in a first-order Amazonian stream, analyzing the trophic ecology, feeding strategies and ecomorphological attributes related to the use of food and space by these species. Fish were captured in May and September 2010. The stomach contents of 60 individuals were analyzed and quantified volumetrically to characterize the feeding ecology of both species. Eleven morphological attributes were measured in 20 specimens and combined in nine ecomorphological indices. Both species had an omnivorous-invertivorous diet and consumed predominantly allochthonous items. Both showed a tendency to a generalist diet, but intrapopulational variation in resource use was also detected. Overall feeding niche overlap was high, but differed between seasons: low during the rainy season and high in the dry season. In the latter, the food niche overlap was asymmetric because C. nigrofasciata consumed several prey of P. aff. brevis...

The reproductive ecology of two naturalised Erica species (Ericaceae) in the Adelaide hills: the rise and fall of two 'would-be' weeds?

Turner, D.; Conran, J.
Fonte: Royal Soc South Australia Inc Publicador: Royal Soc South Australia Inc
Tipo: Artigo de Revista Científica
Publicado em //2004 EN
Relevância na Pesquisa
46.14%
The pollination biology and reproductive ecology of the newly naturalised species Erica cinerea from Europe and E. glandulosa from South Africa (Ericaceae) are reported from the Adelaide Hills from surveys undertaken in 1995 and 2003. Examination of UV floral reflectance, nectar composition and floral visitors found that E. cinerea was honeybee pollinated (although the bees also practiced nectar theft by chewing through the corolla tube), whereas E. glandulosa was probably pollinated by New Holland Honeyeaters (Phylidonyris novaehollandiae: Meliphagidae) which filled the niche of the nectariniid Sunbirds which pollinate it in South Africa.; D. Turner & J.G. Conran; Copyright © 2004 Royal Society of South Australia

Reliable identification of mycobacterial species by PCR-restriction enzyme analysis (PRA)-hsp65 in a reference laboratory and elaboration of a sequence-based extended algorithm of PRA-hsp65 patterns

Chimara, Erica ; Ferrazoli, Lucilaine ; Ueky, Suely ; Martins, Maria ; Durham, Alan Mitchell; Arbeit, Robert D; Leão, Sylvia 
Fonte: Biblioteca Digital da Produção Intelectual da USP Publicador: Biblioteca Digital da Produção Intelectual da USP
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
36.28%
Abstract Background Identification of nontuberculous mycobacteria (NTM) based on phenotypic tests is time-consuming, labor-intensive, expensive and often provides erroneous or inconclusive results. In the molecular method referred to as PRA-hsp65, a fragment of the hsp65 gene is amplified by PCR and then analyzed by restriction digest; this rapid approach offers the promise of accurate, cost-effective species identification. The aim of this study was to determine whether species identification of NTM using PRA-hsp65 is sufficiently reliable to serve as the routine methodology in a reference laboratory. Results A total of 434 NTM isolates were obtained from 5019 cultures submitted to the Institute Adolpho Lutz, Sao Paulo Brazil, between January 2000 and January 2001. Species identification was performed for all isolates using conventional phenotypic methods and PRA-hsp65. For isolates for which these methods gave discordant results, definitive species identification was obtained by sequencing a 441 bp fragment of hsp65. Phenotypic evaluation and PRA-hsp65 were concordant for 321 (74%) isolates. These assignments were presumed to be correct. For the remaining 113 discordant isolates...

Mitochondrial genome sequences reveal evolutionary relationships of the Phytophthora Ic clade species

Lassiter, Erica S.; Russ, Carsten; Nusbaum, Chad; Zeng, Qiandong; Saville, Amanda; Olarte, Rodrigo; Carbone, Ignazio; Hu, Chia-Hui; Seguin-Orlando, Andaine; Samaniego, Jose A; Thorne, Jeffrey L.; Ristaino, Jean B.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
35.97%
Phytophthora infestans is one of the most destructive plant pathogens of potato and tomato globally. The pathogen is closely related to four other Phytophthora species including P. phaseoli, P. ipomoeae, P. mirabilis, and P. andina that are important pathogens of other wild and domesticated hosts. P. andina is an interspecific hybrid between P. infestans and an unknown Phytophthora species. We have sequenced mitochondrial genomes of the sister species of P. infestans in order to resolve the evolutionary relationships within the clade. Phylogenetic analysis indicates that the P. phaseoli mitochondrial lineage is basal within the clade. P. mirabilis and P. ipomoeae are sister lineages and share a common ancestor with the Ic mitochondrial lineage of P. andina. These lineages in turn are sister to the P. infestans and P. andina Ia mitochondrial lineages. The P. andina Ic lineage diverged much earlier than the P. andina Ia mitochondrial lineage and P. infestans. The presence of two mitochondrial lineages in P. andina supports the hybrid nature of this species. The ancestral state of the P. andina Ic lineage in the tree and its occurrence only in the Andean regions of Ecuador, Colombia and Peru suggests further sampling in the Americasis warranted to understand the distribution of this species hybrid in nature.

Condensed tannin content of several shrub species from a mountain area in northern Spain, and its relationship to various indicators of nutritive value

Frutos, Pilar; Hervás, Gonzalo; Ramos, Graciano; Giráldez, Francisco Javier; Mantecón, Ángel R.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artículo Formato: 129716 bytes; application/pdf
ENG
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36.14%
http://dx.doi.org/10.1016/S0377-8401(01)00323-6; The condensed tannin (CT) content of eight shrub species (Cytisus purgans, Cytisus scoparius, Genista florida, Genista occidentalis, Calluna vulgaris, Erica arborea, Erica australis and Juniperus communis) from a grazing mountain area of northern Spain was analysed and related to various indicators of nutritive value. Chemical composition, in vitro gas production, OM degradation and true DM digestibility were evaluated in samples collected in January and June. With the exception of two samples comprised of considerable amounts of flowers, the shrub legumes examined had low contents of CT (less than 6.51 g quebracho tannin equivalents/kg DM) which would generally be considered unlikely to affect digestion of nutrients in the gastrointestinal tract of animals. However, Ericaceae species and J. communis, which are evergreen species, showed a high CT content (higher than 176 g quebracho tannin equivalents/kg DM) throughout the year. CT were negatively correlated (P<0.05) with OM degradation and cumulative gas production, and positively correlated with lag time, which is consistent with the extensively reported suppressive effect of condensed tannins on rumen degradation and on the interference of these compounds with microbial attachment to feeds. The positive correlation between these plant secondary compounds and the partitioning factor (OM degradation/total gas production) indicates that the effect of CT is more strongly reflected in the reduction of gas production than in the reduction of OM degradation.; This work was supported by the Junta de Castilla y León (Projects CSI 3/99).; Peer reviewed

Response of plant species richness and primary productivity in shrublands along a north–south gradient in Europe to seven years of experimental warming and drought: reductions in primary productivity in the heat and drought year of 2003

Peñuelas, Josep; Prieto, Patricia; Beier, Claus; Cessaraccio, Carla; De Angelis, Paolo; De Dato, Giovanbattista; Emmett, Bridget A.; Estiarte, Marc; Garadnai, János; Gorissen, Antonie; Lang, Edit Kovacs; Kröel-Dulay, György; Llorens, Laura; Pellizaro,
Fonte: Universidade Autônoma de Barcelona Publicador: Universidade Autônoma de Barcelona
Tipo: Artigo de Revista Científica Formato: application/pdf
Publicado em //2007 ENG
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We used a nonintrusive field experiment carried out at six sites – Wales (UK), Denmark (DK), the Netherlands (NL), Hungary (HU), Sardinia (Italy – IT), and Catalonia (Spain – SP) – along a climatic and latitudinal gradient to examine the response of plant species richness and primary productivity to warming and drought in shrubland ecosystems. The warming treatment raised the plot daily temperature by ca. 1 °C, while the drought treatment led to a reduction in soil moisture at the peak of the growing season that ranged from 26% at the SP site to 82% in the NL site. During the 7 years the experiment lasted (1999–2005), we used the pin-point method to measure the species composition of plant communities and plant biomass, litterfall, and shoot growth of the dominant plant species at each site. A significantly lower increase in the number of species pin-pointed per transect was found in the drought plots at the SP site, where the plant community was still in a process of recovering from a forest fire in 1994. No changes in species richness were found at the other sites, which were at a more mature and stable state of succession and, thus less liable to recruitment of new species. The relationship between annual biomass accumulation and temperature of the growing season was positive at the coldest site and negative at the warmest site. The warming treatment tended to increase the aboveground net primary productivity (ANPP) at the northern sites. The relationship between annual biomass accumulation and soil moisture during the growing season was not significant at the wettest sites...

Seasonal fluctuation in the population of Harmonia axyridis (Pallas, 1773) (Coleoptera: Coccinellidae) and co-occurrence with other Coccinellids in the Federal District of Brazil

Harterreiten-Souza, Érica Sevilha; Togni, Pedro Henrique Brum; Milane, Paloma Virgínia Gambarra Nitão; Cavalcante, Kelly Ramalho; Medeiros, Maria Alice de; Pires, Carmen Silvia Soares; Sujii, Edison Ryoiti
Fonte: Universidade de São Paulo. Museu de Zoologia Publicador: Universidade de São Paulo. Museu de Zoologia
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; Formato: application/pdf
Publicado em 01/01/2012 ENG
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35.99%
A joaninha asiática, Harmonia axyridis (Pallas, 1773), foi primeiramente registrada no Brasil em 2002 no Estado do Paraná, sendo posteriormente registrada nos estados de São Paulo e Minas Gerais. Essa espécie pode colonizar novas áreas e tornar-se dominante na comunidade local, reduzindo a densidade e diversidade de espécies nativas, principalmente de coccinelídeos. O objetivo deste trabalho foi registrar a presença de H. axyridis no Distrito Federal, a flutuação populacional e a sua co-ocorrência com outros coccinelídeos. As coletas foram realizadas em uma propriedade rural particular em Taguatinga e no campo experimental da Embrapa Hortaliças no Gama, Distrito Federal, entre agosto/2008-janeiro/2010, utilizando coleta direta dos indivíduos sobre as plantas. Foram coletados 881 coccinelídeos, sendo que destes 110 pertencem à espécie H. axyridis exclusivamente do grupo succinea, nas seguintes plantas: tomate, coentro, milho verde, repolho, couve, couve-flor, brócolis, pepino. Também foi observada a sua co-ocorrência com outras espécies de joaninhas: Cycloneda sanguinea (Linnaeus, 1763), Hippodamia convergens (Guerin-Meneville 1842), Eriopis connexa (German, 1824), Scymnus sp., Nephaspis sp., Azya luteipes (Mulsant...

Effect of Prosopis flexuosa on understory species and its importance to pastoral management in woodlands of the Central Monte Desert

Cesca,Erica M; Passera,Carlos; Villagra,Pablo E; Alvarez,Juan A
Fonte: Revista de la Facultad de Ciencias Agrarias. Universidad Nacional de Cuyo Publicador: Revista de la Facultad de Ciencias Agrarias. Universidad Nacional de Cuyo
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2012 EN
Relevância na Pesquisa
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In the Monte Biogeographic Province, located in the arid region of Argentina, the presence of Prosopis flexuosa DC. produces spatial heterogeneity through edaphic modifications and microclimate changes. This results in vegetation patches differing in species composition and abundance. However, this interaction can be modified by the occurrence of gradients of biotic stress or disturbance intensity. In particular, grazing has been observed to enhance or reduce vegetation heterogeneity. Such complex of interactions could determine forage availability for cattle in one of the driest areas of the Monte Desert. We assessed the effect of Prosopis on understory species and analyzed whether the outcomes of this interaction differed with distance to watering points, as a proxy of grazing intensity, in the Northeast of Mendoza Province, Argentina. We used a two-way factorial design including the following factors: 1) microsite (under the cover of P. flexuosa trees and in intercanopy microsites) and 2) distance to watering points ("near the watering point", 500-700 m away, and "far from the watering point", 3-4 km away). Cover of each species, total cover, bare soil, and litter were recorded, and plant diversity, richness, and evenness were estimated with the modified Point Quadrat method. Results showed that P. flexuosa cover...

Prey selection by two benthic fish species in a Mato Grosso stream, Rio de Janeiro, Brazil

Ferreira Rezende,Carla; Mazzoni,Rosana; Pellegrini Caramaschi,Érica; Rodrigues,Daniela; Moraes,Maíra
Fonte: Revista de Biología Tropical Publicador: Revista de Biología Tropical
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2011 EN
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Key to understand predator choice is the relationship between predator and prey abundance. There are few studies related to prey selection and availability. Such an approach is still current, because the ability to predict aspects of the diet in response to changes in prey availability is one of the major problems of trophic ecology. The general objective of this study was to evaluate prey selection by two species (Characidium cf. vidali and Pimelodella lateristriga) of the Mato Grosso stream, in Saquarema, Rio de Janeiro, Brazil. Benthos and fishes were collected in June, July and September of 2006 and January and February of 2007. Fish were collected with electric fishing techniques and benthos with a surber net. Densities of benthic organisms were expressed as the number of individuals per/m2. After sampling, the invertebrates were fixed in 90% ethanol, and, in the laboratory, were identified to the lowest taxonomical level. Approximately, seventy individuals from each species were selected randomly in each month. Fishes were fixed in 10% formalin in the field and transferred to 70o GL ethanol in the laboratory. Fishes had their stomachs removed for subsequent analysis. Fish diet was described according to the numeric frequency method. The Manly Electivity I ndex was applied in order to verify prey selection. The most abundant families in both benthos and diet of both fish species were the same...

Mesohabitat indicator species in a coastal stream of the Atlantic rainforest, Rio de Janeiro-Brazil

Ferreira Rezende,Carla; Moraes,Maíra; Resende Manna,Luisa; Pereira Leitão,Rafael; Pelegrinni Caramaschi,Érica; Mazzoni,Rosana
Fonte: Revista de Biología Tropical Publicador: Revista de Biología Tropical
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2010 EN
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The Mato Grosso is a typical Atlantic Forest stream located on the East coast of Brazil, approximately 70km from Rio de Janeiro city. From its source at about 800m a.s.l, the stream drains a 30km² area of the Northwestern part of the municipality of Saquarema, state of Rio de Janeiro and flows into the Saquarema Lagoon system. We hypothesized that fish species occupy distinct mesohabitats, with the prediction that their occurrences and densities differ among the microhabitats of riffles, runs and pools. A 250m-long stretch of the stream located in its uppermost part was selected for this study, where it becomes second-order. Mesohabitat description and their fish characterization were undertaken. Fish sampling was conducted by electroshocking and after their identification and counting, they were returned to the stream. For mesohabitat characterization, a Discriminant Function Analysis (DA) was applied. The total number of samples was estimated by the Zippin method and the recorded densities were used as an Indicator Species Analysis (ISA), followed by a Monte Carlo test for 1 000 permutations. The DA significantly separated the three predetermined mesohabitats (pool, riffle and run) (WL=0.13, F=187.70, p=0.001). We found five species of fishes...