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| Registros recuperados: 13 | |
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| Silva,Marcelo Aparecido de Souza; Varassin,Isabela Galarda. |
| ABSTRACT Plant size and clonality are important traits for explaining the reproductive effort of clonal plants. Larger plants can invest more resources into reproduction, and clonality is known to increase reproductive effort. Moreover, reproductive effort is influenced by environmental variation, and so the spatial distribution of plants may affect plant reproductive effort. We investigated the effect of plant size, clonality and spatial distribution on the reproductive effort of Vriesea carinata in the Atlantic Forest in the state of Paraná, Brazil. We marked twenty individual plants and measured their rosette size, biomass and number, as well as rosette reproductive effort (number of flowers, fruits and seeds). We also evaluated the relationship between... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Clonal growth; Morphological variation; Reproductive effort; RNSM; Vriesea. |
| Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-33062016000300401 |
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| Gutman, Mario; Agricultural Research Organization; mgutman@shani.net; Noy-Meir, Imanuel; Hebrew University of Jerusalem; noymeir@agri.huji.ac.il; Pluda, Daniel C; Volcani Center;; Seligman, No'am; Volcani Center; noamseli@netvision.net.il; Rothman, Steven; ;; Sternberg, Marcelo; Tel Aviv University; MarceloS@tauex.tau.ac.il. |
| A two-year experiment was conducted in northeastern Israel to study the effects of various defoliation regimes on biomass partitioning between vegetative and reproductive structures in a perennial and an annual Mediterranean grass. Greater insight into the mechanisms regulating biomass partitioning after defoliation enables ecologists and rangeland managers to interpret and predict population and community dynamics in Mediterranean grasslands more efficiently. Two typical Mediterranean grasses, Triticum dicoccoides, an annual species, and Hordeum bulbosum, a perennial species, were grown in containers in the open. They were subjected to a series of defoliation treatments that comprised three clipping frequencies and three clipping heights in a full... |
| Tipo: Peer-Reviewed Reports |
Palavras-chave: Annual vs. perennial grasses; Biomass partitioning; Defoliation treatments; Grasslands; Grazing response; Hordeum bulbosum; Israel; Mediterranean; Reproductive effort; Triticum dicoccoides; Vegetative vs. reproductive structures.. |
| Ano: 2001 |
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| Royer, J; Seguineau, Catherine; Park, K; Pouvreau, Stephane; Choi, K; Costil, K. |
| Two methods were used to estimate the reproductive output of female Pacific oysters reared in Normandy: histology with image analysis and ELISA (Enzyme-Linked lmmunoSorbent Assay) which allowed the quantification of egg protein. Condition indices, gonad area and gametogenetic stages of the oysters were determined in the entire population (males and females) between May and October 2005. All investigations were performed in 3 age classes: oysters in their first, second or third years (corresponding to spat, half-grown and market-sized oysters, respectively). Both quantitative histology and ELISA provided similar results in terms of reproductive effort (illustrated by the gonado-somatic index, GSI) except during the GSI drop, corresponding to spawning, which... |
| Tipo: Text |
Palavras-chave: Reproductive effort; Image analysis; Gametogenetic cycle; ELISA; Crassostrea gigas; Condition index. |
| Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-4305.pdf |
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| De Decker, Sophie; Normand, Julien; Saulnier, Denis; Pernet, Fabrice; Castagnet, Sophie; Boudry, Pierre. |
| Several Vibrio species are known to be pathogenic to the Pacific oyster Crassostrea gigas. Survival varies according to pathogen exposure and high mortality events usually occur in summer during gametogenesis. In order to study the effects of gametogenetic status and ploidy (a factor known to affect reproduction allocation in oysters) on vibriosis survival, we conducted two successive experiments. Our results demonstrate that a common bath challenge with pathogenic Vibrio splendidus and Vibrio aestuarianus on a mixture of mature, spawning and non-mature oysters can lead to significant mortality. Previous bath challenges, which were done using only non-mature oysters, had not produced mortality. Immunohisto-chemical analyses showed the affinity of Vibrio... |
| Tipo: Text |
Palavras-chave: Experimental vibriosis; Crassostrea gigas; Vibrio; Survival distribution function; Triploidy; Reproductive effort. |
| Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00030/14108/11368.pdf |
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| Pouvreau, Stephane; Gangnery, Aline; Tiapari, Jerome; Lagarde, Franck; Garnier, Matthieu; Bodoy, Alain. |
| The gametogenic cycle and the reproductive effort of the blacklip pearl oyster, Pinctada margaritifera, cultivated in Takapoto lagoon were studied for a 1-year period (March 1997-April 1998) by bimonthly observations of gonadal sections, dry tissue weights and gonadal index in a population of pearl oyster composed of three age-groups. pearl oysters attained sexual maturity in the end of their first year (height approximate to 40 mm), implying that P. margaritifera is a late-maturing species in comparison with other Pteriidae. This species was also confirmed to be a marked protandrous successive hermaphrodite in culture, with 100 % of males at first maturity and 75 % in older pearl oyster (height > 120 mm). The general pattern of gametogenic activity,... |
| Tipo: Text |
Palavras-chave: French Polynesia; Reproductive effort; Reproductive cycle; Tropical aquaculture; Gametogenesis; Blacklip pearl oyster; Polynésie française; Effort de reproduction; Cycle de reproduction; Aquaculture tropicale; Gamétogenèse; Huître perlière. |
| Ano: 2000 |
URL: http://archimer.ifremer.fr/doc/2000/publication-1391.pdf |
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| Soletchnik, Patrick; Le Moine, Olivier; Faury, Nicole; Razet, Daniel; Geairon, Philippe; Robert, Stephane; Goulletquer, Philippe; Taillade, Sylvie. |
| The 1999 monitoring of the C. gigas mortality rates showed a 32 to 40% loss for the on-bottom rearings located on the Ronce-Perquis oyster bank. In 1997, the averaged mortality rate varied between 23 and 29% without significant site effect. These mortality rates were ranging from 17 to 32% in 1998 with significant limited mortality rate on site 4 (17%). However, those rates were underestimated by 7 to 8%, based on our 1999 study, Actually, the spatial distribution for these rates on 2 experimental sites divided into 25 subunits demonstrated a large variability ranging from 17-37% and 22-56% for sites 1 and 2, respectively. In spite this large variability, the mortality rates results were larger on the muddy bottom site. In contrast to site 1, the oysters... |
| Tipo: Text |
Palavras-chave: Bay of Marennes Oleron; Crassostrea gigas; Reproductive effort; Biochemical composition; Growth; Sampling strategy; Mortality rates; Bassin de Marennes Oléron; Crassostrea gigas; Effort de reproduction; Composition biochimique; Croissance; Méthodologie d'estimation; Taux de mortalité. |
| Ano: 2000 |
URL: http://archimer.ifremer.fr/doc/2000/rapport-1641.pdf |
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| Pouvreau, Stephane; Bourles, Yves; Lefebvre, Sebastien; Gangnery, Aline; Alunno-bruscia, Marianne. |
| The Dynamic Energy Budget (DEB) model (Kooijman, S.A.L.M., 1986. Energy budgets can explain body size relations. J. Theor. Biol. 121, 269¿282; Kooijman, S.A.L.M., 2000. Dynamic Energy and Mass Budgets in Biological Systems. Cambridge University Press, Cambridge, 424 pp.) has been adapted to describe the dynamics of growth and reproduction of the Pacific oyster (Crassostrea gigas) reared in different areas under conditions ranging from controlled to natural. The values of the model parameters were estimated from available physiological data and from published information. The sets of data used to validate the model came from three long-term growth experiments (> 5 months) performed on Pacific oysters reared under different conditions of food and... |
| Tipo: Text |
Palavras-chave: Reproductive effort; Reproduction; Growth; Ecophysiology; Dynamic energy budget; Crassostrea gigas. |
| Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-1817.pdf |
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| Bernard, Ismael; De Kermoysan, Goulwen; Pouvreau, Stephane. |
| DEB theory can be used to obtain a detailed description of energy allocation in organisms and the control of this allocation by temperature and food concentration. In this study, we modified the model of Bourlès et al. (2009) developed for the Pacific oyster, Crassostrea gigas, to improve the description of reproductive effort. The model was amended in two ways: a new set of parameters was incorporated and a full description of gonad construction in spring was added, with a new state variable. The application of this model to a dataset for oyster growth measured in four bays over two years showed that this model better described reproductive effort, without modifying overall growth dynamics. We then explored the reproductive responses of oysters to their... |
| Tipo: Text |
Palavras-chave: DEB model; Crassostrea gigas; Gametogenesis; Reproductive effort; Spawning date; Functional response. |
| Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00059/17047/14606.pdf |
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| Registros recuperados: 13 | |
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