Maurício Faria | UNIMONTES universidade estadual de Montes Claros (original) (raw)
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Papers by Maurício Faria
Resumo No sistema Baccharis dracunculifolia/Neopelma baccharidis, os efeitos dos aspectos populac... more Resumo No sistema Baccharis dracunculifolia/Neopelma baccharidis, os efeitos dos aspectos populacionais da planta hospedeira na abundância das galhas e seus parasitóides ainda são pobremente estudados. Este trabalho teve como objetivo avaliar ...
PLoS ONE, 2014
Background: The complex network of direct and indirect relationships determines not only the spec... more Background: The complex network of direct and indirect relationships determines not only the species abundances but also the community characteristics such as diversity and stability. In this context, seed predation is a direct interaction that affects the reproductive success of the plant. For Acrocomia aculeata, the seed predation by Pachymerus cardo and Speciomerus revoili in post-dispersal may destroy more than 70% of the propagules and is influenced by the herbivory of the fruits during pre-dispersal. Fruits of plants with a higher level of herbivory during pre-dispersal are less attacked by predators in post-dispersal. We proposed a hypothesis that describes this interaction as an indirect defense mediated by fungi in a multitrophic interaction. As explanations, we proposed the predictions: i) injuries caused by herbivores in the fruits of A. aculeata favor fungal colonization and ii) the colonization of A. acuelata fruit by decomposing fungi reduces the selection of the egg-laying site by predator.
Resumo No sistema Baccharis dracunculifolia/Neopelma baccharidis, os efeitos dos aspectos populac... more Resumo No sistema Baccharis dracunculifolia/Neopelma baccharidis, os efeitos dos aspectos populacionais da planta hospedeira na abundância das galhas e seus parasitóides ainda são pobremente estudados. Este trabalho teve como objetivo avaliar ...
Acta Botanica Brasilica, 2013
The plant population dynamic is affected by ecological and evolutionary processes that operate at... more The plant population dynamic is affected by ecological and evolutionary processes that operate at all stages of the plant life cycle. The aim of this study was to characterize the seed and seedling performance of Copaifera langsdorffii by testing four hypotheses: the resource concentration hypothesis; the relationship between seed size and germinability hypothesis; the relationship between seed size and seedling vigor hypothesis; and the intraspecific seedling competition hypothesis. All seeds used in the experiments were collected from 35 C. langsdorffii plants located in a fragment of the Brazilian cerrado (savanna). The number of fruits per plant negatively affected Rhinochenus brevicollis attacks on C. langsdorffii seeds. Therefore, this result does not support the resource concentration hypothesis, and predator satiation was used in order to explain the observed result. In general, seed germinability (percentage and time to emergence) was not influenced by seed size. The homogeneity of the experimental design, together with an abundant water supply, may have masked the effects of seed size on germinability. Seed size positively affected seedling development, corroborating the expected relationship between seed size and seedling vigor. The number of se edling per plastic bags negatively affected the growth of C. langsdorffii. The nutrient-limited soil probably promoted the below-ground competition for nutrients among seedlings. Finally, the role of evolutionary and ecological factors on C. langsdorffii population dynamics is discussed.
Annals of botany, 2003
Patterns of phenological variation and reproductive investment were studied in the dioecious shru... more Patterns of phenological variation and reproductive investment were studied in the dioecious shrub Baccharis dracunculifolia DC (Asteraceae), and possible consequences on survivorship were evaluated. The sex ratio was determined in a natural field population (n = 921) of B. dracunculifolia in Belo Horizonte, Brazil. Fifty-two males and 56 females were sampled at random from this population. During the reproductive season of 1999, inflorescence production, shoot growth and mortality, and xylem water potential were recorded for each individual. The population sex ratio was male-biased (1.27 : 1, P < 0.05), and was associated with a higher mortality of female shoots (38.4 vs. 23.1 %, P < 0.05), and individuals (17.8 vs. 11.5 %, P < 0.1), despite lower water stress in female plants. Flowering phenology also differed between the sexes, with males producing more inflorescences, and earlier, than females. Owing to fruit maturation, the number of inflorescences supported by females...
Resumo No sistema Baccharis dracunculifolia/Neopelma baccharidis, os efeitos dos aspectos populac... more Resumo No sistema Baccharis dracunculifolia/Neopelma baccharidis, os efeitos dos aspectos populacionais da planta hospedeira na abundância das galhas e seus parasitóides ainda são pobremente estudados. Este trabalho teve como objetivo avaliar ...
PLoS ONE, 2014
Background: The complex network of direct and indirect relationships determines not only the spec... more Background: The complex network of direct and indirect relationships determines not only the species abundances but also the community characteristics such as diversity and stability. In this context, seed predation is a direct interaction that affects the reproductive success of the plant. For Acrocomia aculeata, the seed predation by Pachymerus cardo and Speciomerus revoili in post-dispersal may destroy more than 70% of the propagules and is influenced by the herbivory of the fruits during pre-dispersal. Fruits of plants with a higher level of herbivory during pre-dispersal are less attacked by predators in post-dispersal. We proposed a hypothesis that describes this interaction as an indirect defense mediated by fungi in a multitrophic interaction. As explanations, we proposed the predictions: i) injuries caused by herbivores in the fruits of A. aculeata favor fungal colonization and ii) the colonization of A. acuelata fruit by decomposing fungi reduces the selection of the egg-laying site by predator.
Resumo No sistema Baccharis dracunculifolia/Neopelma baccharidis, os efeitos dos aspectos populac... more Resumo No sistema Baccharis dracunculifolia/Neopelma baccharidis, os efeitos dos aspectos populacionais da planta hospedeira na abundância das galhas e seus parasitóides ainda são pobremente estudados. Este trabalho teve como objetivo avaliar ...
Acta Botanica Brasilica, 2013
The plant population dynamic is affected by ecological and evolutionary processes that operate at... more The plant population dynamic is affected by ecological and evolutionary processes that operate at all stages of the plant life cycle. The aim of this study was to characterize the seed and seedling performance of Copaifera langsdorffii by testing four hypotheses: the resource concentration hypothesis; the relationship between seed size and germinability hypothesis; the relationship between seed size and seedling vigor hypothesis; and the intraspecific seedling competition hypothesis. All seeds used in the experiments were collected from 35 C. langsdorffii plants located in a fragment of the Brazilian cerrado (savanna). The number of fruits per plant negatively affected Rhinochenus brevicollis attacks on C. langsdorffii seeds. Therefore, this result does not support the resource concentration hypothesis, and predator satiation was used in order to explain the observed result. In general, seed germinability (percentage and time to emergence) was not influenced by seed size. The homogeneity of the experimental design, together with an abundant water supply, may have masked the effects of seed size on germinability. Seed size positively affected seedling development, corroborating the expected relationship between seed size and seedling vigor. The number of se edling per plastic bags negatively affected the growth of C. langsdorffii. The nutrient-limited soil probably promoted the below-ground competition for nutrients among seedlings. Finally, the role of evolutionary and ecological factors on C. langsdorffii population dynamics is discussed.
Annals of botany, 2003
Patterns of phenological variation and reproductive investment were studied in the dioecious shru... more Patterns of phenological variation and reproductive investment were studied in the dioecious shrub Baccharis dracunculifolia DC (Asteraceae), and possible consequences on survivorship were evaluated. The sex ratio was determined in a natural field population (n = 921) of B. dracunculifolia in Belo Horizonte, Brazil. Fifty-two males and 56 females were sampled at random from this population. During the reproductive season of 1999, inflorescence production, shoot growth and mortality, and xylem water potential were recorded for each individual. The population sex ratio was male-biased (1.27 : 1, P < 0.05), and was associated with a higher mortality of female shoots (38.4 vs. 23.1 %, P < 0.05), and individuals (17.8 vs. 11.5 %, P < 0.1), despite lower water stress in female plants. Flowering phenology also differed between the sexes, with males producing more inflorescences, and earlier, than females. Owing to fruit maturation, the number of inflorescences supported by females...