Sabiia Seb
PortuguêsEspañolEnglish
Embrapa
        Busca avançada

Botão Atualizar


Botão Atualizar

Ordenar por: RelevânciaAutorTítuloAnoImprime registros no formato resumido
Registros recuperados: 9
Primeira ... 1 ... Última
Imagem não selecionada

Imprime registro no formato completo
Colorful invasion in permissive Neotropical ecosystems: establishment of ornamental non-native poeciliids of the genera Poecilia/Xiphophorus (Cyprinodontiformes: Poeciliidae) and management alternatives Neotropical Ichthyology
Magalhães,André Lincoln Barroso; Jacobi,Claudia Maria.
ABSTRACT Headwater creeks are environments susceptible to invasion by non-native fishes. We evaluated the reproduction of 22 populations of the non-native livebearers guppy Poecilia reticulata, black molly Poecilia sphenops, Yucatan molly Poecilia velifera, green swordtail Xiphophorus hellerii, southern platyfish Xiphophorus maculatus, and variable platyfish Xiphophorus variatus during an annual cycle in five headwater creeks located in the largest South American ornamental aquaculture center, Paraíba do Sul River basin, southeastern Brazil. With few exceptions, females of most species were found reproducing (stages 2, 3, 4) all year round in the creeks and gravid females of all species showed small sizes indicating stunting. Juveniles were frequent in all...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Aquaculture; Invasive species; Livebearers; Reproduction; Stream.
Ano: 2017 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252017000100204
Imagem não selecionada

Imprime registro no formato completo
Desempenho germinativo da invasora Leucaena leucocephala (Lam.) de Wit. e comparação com Caesalpinia ferrea Mart. ex Tul. e Caesalpinia pulcherrima (L.) Sw. (Fabaceae) Acta Botanica
Fonseca,Nilson Gonçalves da; Jacobi,Claudia Maria.
O sucesso das plantas na colonização de novas áreas está fortemente relacionado ao comportamento germinativo das sementes nas condições ambientais locais. O objetivo deste trabalho foi comparar o desempenho germinativo da exótica invasora Leucaena leucocephala ao das leguminosas (Caesalpinia ferrea, nativa e C. pulcherrima, exótica) não consideradas invasoras. Sementes não escarificadas foram expostas às temperaturas de 15, 20, 25, 30, 35 e 40 °C, sob um fotoperíodo de 12 horas, durante 100 dias. Tanto a porcentagem final quanto a velocidade de germinação apresentaram diferenças significativas entre as três espécies. C. ferrea teve baixo desempenho, com temperatura ótima para a germinação a 25°C, porcentagem de germinação de 59% e IVG de 0,68 sementes d-1....
Tipo: Info:eu-repo/semantics/article Palavras-chave: Espécie exótica; Germinabilidade; Potencial de invasão; Velocidade de germinação.
Ano: 2011 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062011000100022
Imagem não selecionada

Imprime registro no formato completo
Ecology of neotropical mistletoes: an important canopy-dwelling component of Brazilian ecosystems Acta Botanica
Arruda,Rafael; Fadini,Rodrigo Ferreira; Carvalho,Lucélia Nobre; Del-Claro,Kleber; Mourão,Fabiana Alves; Jacobi,Claudia Maria; Teodoro,Grazielle Sales; Berg,Eduardo van den; Caires,Claudenir Simões; Dettke,Greta Aline.
Mistletoes have been studied in temperate countries regularly because they can be pests of cultivated plants and forest plantations. In comparison with temperate habitats, little is known about the ecology of mistletoes in the Neotropics. More emphasis should be given to neotropical mistletoes because they could be important elements of plant communities, acting as key resources for pollinators, seed dispersers and herbivores. Using a combination of findings from early mistletoe studies and empirical evidence from several recent case studies, we report emerging patterns of mistletoe interactions with associated organisms and propose aims for further studies. There has been increasing interest in working with mistletoes in Brazil. Although there are some...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Hemiparasites; Biological conservation; Host specificity; Host compatibility.
Ano: 2012 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062012000200003
Imagem não selecionada

Imprime registro no formato completo
Effects of the parasitism of Struthanthus flexicaulis (Mart.) Mart. (Loranthaceae) on the fitness of Mimosa calodendron Mart. (Fabaceae), an endemic shrub from rupestrian fields over ironstone outcrops, Minas Gerais State, Brazil Acta Botanica
Mourão,Fabiana Alves; Jacobi,Claudia Maria; Figueira,José Eugênio Côrtes; Batista,Eugênia Kelly Luciano.
Parasitic plants (mistletoes) may alter the growth, reproduction and physiology of their hosts. Mimosa calodendron (Fabaceae) is a legume abundant in rupestrian fields on ironstone outcrops, frequently attacked by the hemiparasite Struthanthus flexicaulis (Loranthaceae). The objective of this study was to evaluate the consequences of parasitism by S. flexicaulis on the fitness of M. calodendron. The intensity of parasitism and mortality on hosts of different sizes was evaluated, and foliage cover, fruit and seed set in parasitized and non-parasitized individuals were compared. More than 65% of a population of 1820 individuals was attacked. Host density positively influenced parasitism. The mortality and number of attacked hosts increased with their crown...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Ironstone; Mimosa; Parasitism; Reproductive success; Struthanthus.
Ano: 2009 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062009000300023
Imagem não selecionada

Imprime registro no formato completo
Host preference of the hemiparasite Struthanthus flexicaulis (Loranthaceae) in ironstone outcrop plant communities, southeast Brazil Acta Botanica
Mourão,Fabiana Alves; Pinheiro,Rafael Barros Pereira; Jacobi,Claudia Maria; Figueira,José Eugênio Côrtes.
Struthanthus flexicaulis is a hemiparasite abundant in ironstone outcrops in southeast Brazil. We evaluated its host preference among species of the plant community, taking into account the abundance and foliage cover of the hosts. The importance of each species in the community and the mortality caused by the parasite were assessed based on a quantitative survey in 10 strips measuring 1m x 50m. The 10,290 individuals belonged to 42 species. Only 15 had a relative abundance in the plant community greater than 1%, of which 12 showed vestiges of parasitism. More than 80% of deaths in the community were associated with parasitism. Non-infected individuals had significantly less mortality rates (7%) than those infected (83%) (²= 1102.4, df = 1, p < 0.001)....
Tipo: Info:eu-repo/semantics/article Palavras-chave: Canga; Iron Quadrangle; Ironstone outcrop; Plant-plant interaction; Parasitism.
Ano: 2016 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062016000100041
Imagem não selecionada

Imprime registro no formato completo
Invasion risks posed by ornamental freshwater fish trade to southeastern Brazilian rivers Neotropical Ichthyology
Magalhães,André Lincoln Barroso de; Jacobi,Claudia Maria.
A model was developed to assess the risk of invasion of ornamental non-native fishes to six rivers in the state of Minas Gerais, southeastern Brazil, with focus on species popularity. Thirty-nine aquarium shops, in six cities, were visited monthly from January to December 2007. In each city, fish species were identified, and their biology and invasion history information was obtained from the literature. We calculated the annual frequency of occurrence and average number of specimens monthly available in stores. Quarterly water temperature and dissolved oxygen data from 1997 to 2007 were obtained for the Velhas, Muriaé, Uberabinha, Sapucaí-Mirim, Doce and Todos os Santos Rivers from public databases. The invasion risk of each species was assessed through a...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Aquarium shops; Aquarium dumping; Fishkeeping; Invasion risk assessment; Non-native fishes.
Ano: 2013 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252013000200433
Imagem não selecionada

Imprime registro no formato completo
Life-forms, pollination and seed dispersal syndromes in plant communities on ironstone outcrops, SE Brazil Acta Botanica
Jacobi,Claudia Maria; Carmo,Flávio Fonseca do.
Rock outcrops play an important role in enhancing plant diversity in montane ecosystems. Ironstone outcrops (cangas) are among the lithotypes less known and most threatened in SE Brazil, due to mining activities. Besides species composition, a key feature to promote their conservation and restoration is the knowledge of the community prevalent life-forms, pollination and seed dispersal syndromes. The analyses were done based on published floristic surveys of cangas in SE Brazil. A total of 353 species of angiosperms (70 families) were assigned to one of the two predominant physiognomies (open areas and forest islands) on ironstone outcrops. Sixteen families responded for 70% of all species. Compared to Raunkiaer's spectrum, phanerophytes were over- and...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Biological spectrum; Cangas; Conservation; Geoedaphic conditions; Rock outcrops.
Ano: 2011 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062011000200016
Imagem não selecionada

Imprime registro no formato completo
Pollination of two species of Vellozia (Velloziaceae) from high-altitude quartzitic grasslands, Brazil Acta Botanica
Jacobi,Claudia Maria; del Sarto,Mário César Laboissiérè.
The pollinators and breeding system of two species of Vellozia (Velloziaceae) from high-altitude quartzitic grasslands in SE Brazil were studied. Vellozia leptopetala is shrubby and grows solely on rocky outcrops, V. epidendroides is herbaceous and grows on stony soils. Both bear solitary, hermaphrodite flowers, and have massive, short-lasting annual blooms. We evaluated the level of self-compatibility and need for pollinators of 50 plants of each species and 20-60 flowers per treatment: hand self- and cross-pollination, spontaneous pollination, agamospermy and control. The behavior of floral visitors on flowers and within plants was recorded. Both species are mostly self-incompatible, but produce a small number of seeds by self-fertilization. The...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Pollen limitation; Geitonogamy; Rocky grasslands; Self-incompatibility; Serra do Cipó.
Ano: 2007 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062007000200007
Imagem não selecionada

Imprime registro no formato completo
Resposta germinativa de duas espécies de Vellozia (Velloziaceae) dos campos rupestres de Minas Gerais, Brasil Acta Botanica
Garcia,Queila de Souza; Jacobi,Claudia Maria; Ribeiro,Beatriz de Aquino.
Foi avaliado o comportamento germinativo das sementes de Vellozia leptopetala Goeth. et Henr., uma espécie de porte arbustivo que cresce sobre afloramentos rochosos e de V. epidendroides Mart. ex Schult. &amp; Schult., uma herbácea que cresce em campos, na Serra do Cipó. As sementes foram submetidas às temperaturas de 15 a 40 ºC, sob luz ou escuro contínuos, com quatro repetições de 25 sementes por tratamento. Ambas as espécies apresentam sementes pequenas, com 1,31 ± 0,06 mm e 1,15 ± 0,01 mm para V. leptopetala e V. epidendroides, respectivamente. As sementes de V. leptopetala sob luz apresentaram germinabilidade alta (95 a 100%) e semelhante na faixa de 20 a 35 ºC e percentuais inferiores a 15 e 40 ºC (34 e 29%, respectivamente). Na condição de...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Fotoblastismo; Temperatura; Campos rupestres; Vellozia leptopetala; Vellozia epidendroides.
Ano: 2007 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062007000200018
Registros recuperados: 9
Primeira ... 1 ... Última
 

Empresa Brasileira de Pesquisa Agropecuária - Embrapa
Todos os direitos reservados, conforme Lei n° 9.610
Política de Privacidade
Área restrita

Embrapa
Parque Estação Biológica - PqEB s/n°
Brasília, DF - Brasil - CEP 70770-901
Fone: (61) 3448-4433 - Fax: (61) 3448-4890 / 3448-4891 SAC: https://www.embrapa.br/fale-conosco

Valid HTML 4.01 Transitional