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Pesquisa : B01.650.940.800.575.912.250.531 [Categoria DeCS]
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  1 / 16 MEDLINE  
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[PMID]:25047026
[Au] Autor:Bruckman D; Campbell DR
[Ad] Endereço:Department of Ecology and Evolutionary Biology, University of California, 321 Steinhaus Hall, Irvine, CA, 92697-2525, USA, dbruckma@uci.edu.
[Ti] Título:Floral neighborhood influences pollinator assemblages and effective pollination in a native plant.
[So] Source:Oecologia;176(2):465-76, 2014 Oct.
[Is] ISSN:1432-1939
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:Pollinators represent an important intermediary by which different plant species can influence each other's reproductive fitness. Floral neighbors can modify the quantity of pollinator visits to a focal species but may also influence the composition of visitor assemblages that plants receive leading to potential changes in the average effectiveness of floral visits. We explored how the heterospecific floral neighborhood (abundance of native and non-native heterospecific plants within 2 m × 2 m) affects pollinator visitation and composition of pollinator assemblages for a native plant, Phacelia parryi. The relative effectiveness of different insect visitors was also assessed to interpret the potential effects on plant fitness of shifts in pollinator assemblage composition. Although the common non-native Brassica nigra did not have a significant effect on overall pollinator visitation rate to P. parryi, the proportion of flower visits that were made by native pollinators increased with increasing abundance of heterospecific plant species in the floral neighborhood other than B. nigra. Furthermore, native pollinators deposited twice as many P. parryi pollen grains per visit as did the nonnative Apis mellifera, and visits by native bees also resulted in more seeds than visits by A. mellifera. These results indicate that the floral neighborhood can influence the composition of pollinator assemblages that visit a native plant and that changes in local flower communities have the potential to affect plant reproductive success through shifts in these assemblages towards less effective pollinators.
[Mh] Termos MeSH primário: Flores/fisiologia
Hydrophyllaceae/fisiologia
Insetos
Polinização
[Mh] Termos MeSH secundário: Animais
Abelhas
Brassica
California
Aptidão Genética
Espécies Introduzidas
Pólen
Reprodução
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Em] Mês de entrada:1503
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:140723
[St] Status:MEDLINE
[do] DOI:10.1007/s00442-014-3023-6


  2 / 16 MEDLINE  
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[PMID]:24616275
[Au] Autor:Thompson HM; Levine SL; Doering J; Norman S; Manson P; Sutton P; von Mérey G
[Ad] Endereço:FERA, Sand Hutton, York, United Kingdom.
[Ti] Título:Evaluating exposure and potential effects on honeybee brood (Apis mellifera) development using glyphosate as an example.
[So] Source:Integr Environ Assess Manag;10(3):463-70, 2014 Jul.
[Is] ISSN:1551-3793
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:This study aimed to develop an approach to evaluate potential effects of plant protection products on honeybee brood with colonies at realistic worst-case exposure rates. The approach comprised 2 stages. In the first stage, honeybee colonies were exposed to a commercial formulation of glyphosate applied to flowering Phacelia tanacetifolia with glyphosate residues quantified in relevant matrices (pollen and nectar) collected by foraging bees on days 1, 2, 3, 4, and 7 postapplication and glyphosate levels in larvae were measured on days 4 and 7. Glyphosate levels in pollen were approximately 10 times higher than in nectar and glyphosate demonstrated rapid decline in both matrices. Residue data along with foraging rates and food requirements of the colony were then used to set dose rates in the effects study. In the second stage, the toxicity of technical glyphosate to developing honeybee larvae and pupae, and residues in larvae, were then determined by feeding treated sucrose directly to honeybee colonies at dose rates that reflect worst-case exposure scenarios. There were no significant effects from glyphosate observed in brood survival, development, and mean pupal weight. Additionally, there were no biologically significant levels of adult mortality observed in any glyphosate treatment group. Significant effects were observed only in the fenoxycarb toxic reference group and included increased brood mortality and a decline in the numbers of bees and brood. Mean glyphosate residues in larvae were comparable at 4 days after spray application in the exposure study and also following dosing at a level calculated from the mean measured levels in pollen and nectar, showing the applicability and robustness of the approach for dose setting with honeybee brood studies. This study has developed a versatile and predictive approach for use in higher tier honeybee toxicity studies. It can be used to realistically quantify exposure of colonies to pesticides to allow the appropriate dose rates to be determined, based on realistic worst-case residues in pollen and nectar and estimated intake by the colony, as shown by the residue analysis. Previous studies have used the standard methodology developed primarily to identify pesticides with insect-growth disrupting properties of pesticide formulations, which are less reliant on identifying realistic exposure scenarios. However, this adaptation of the method can be used to determine dose-response effects of colony level exposure to pesticides with a wide range of properties. This approach would limit the number of replicated tunnel or field-scale studies that need to be undertaken to assess effects on honeybee brood and may be of particular benefit where residues in pollen and nectar are crop- and/or formulation-specific, such as systemic seed treatments and granular applications.
[Mh] Termos MeSH primário: Abelhas/efeitos dos fármacos
Glicina/análogos & derivados
Herbicidas/toxicidade
[Mh] Termos MeSH secundário: Animais
Abelhas/crescimento & desenvolvimento
Abelhas/metabolismo
Glicina/análise
Glicina/toxicidade
Herbicidas/análise
Hydrophyllaceae
Larva/efeitos dos fármacos
Larva/crescimento & desenvolvimento
Larva/metabolismo
Néctar de Plantas/química
Pólen/química
Medição de Risco/métodos
Testes de Toxicidade/métodos
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Herbicides); 0 (Plant Nectar); 4632WW1X5A (glyphosate); TE7660XO1C (Glycine)
[Em] Mês de entrada:1502
[Cu] Atualização por classe:151119
[Lr] Data última revisão:
151119
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:140312
[St] Status:MEDLINE
[do] DOI:10.1002/ieam.1529


  3 / 16 MEDLINE  
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[PMID]:24738921
[Au] Autor:Sigsgaard L; Betzer C; Naulin C; Eilenberg J; Enkegaard A; Kristensen K
[Ad] Endereço:1 University of Copenhagen, Department of Agriculture and Ecology, Zoology Group, Thorvaldsensvej 40, DK-1871 Frederiksberg C, Denmark.
[Ti] Título:The effect of floral resources on parasitoid and host longevity: prospects for conservation biological control in strawberries.
[So] Source:J Insect Sci;13:104, 2013.
[Is] ISSN:1536-2442
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The strawberry tortricid, Acleris comariana Lienig and Zeller (Lepidoptera: Tortricidae) is an important pest in Danish strawberry production. Its most common parasitoid is Copidosoma aretas (Walker) (Hymenoptera: Chalcidoidea: Encyrtidae). To identify selective flowering plants that could be used to increase functional biodiversity, the longevity of C. aretas and its host A. comariana was assessed on 5 flowering species: buckwheat, Fagopyrum esculentum Moench (Caryophyllales: Polygonaceae); borage, Borago officinalis L. (Boraginaceae); strawberry, Fragaria x ananassa Duchesne (Rosales: Rosaceae); phacelia, Phacelia tanacetifolia Bentham (Boraginaceae); and dill, Anethum graveolens L. (Apiales: Apiaceae). Dill was only tested with C. aretas. Sucrose and pollen served as positive controls, and pure water as a negative control. In a subsequent field experiment, A. comariana larval density was assessed at 1, 6, and 11 m distances from buckwheat flower strips in 3 fields. The proportion of field-collected larvae that were parasitized by C. aretas or fungi was assessed. Among the tested floral diets, buckwheat was superior for C. aretas, increasing its longevity by 1.4 times compared to water. Although buckwheat also increased longevity of A. comariana, its longevity and survival on buckwheat, borage, and strawberry was not significantly different, so buckwheat was chosen for field experiments. A. comariana densities in the 3 fields with sown buckwheat flower strips were 0.5, 4.0, and 8.3 larvae per m per row of strawberry respectively. Of the collected larvae, a total of 1%, 39%, and 65% were parasitized by C. aretas, respectively. The density of A. comariana and the proportion parasitized by C. aretas were highly significantly correlated. Distance from floral strips had no significant effect on either A. comariana larval density or on the proportion of individuals parasitized by C. aretas. Few other parasitoids emerged from collected larvae, and no larvae were infected by entomopathogenic fungi. Still, total A. comariana mortality was significantly affected by distance to flower strips, with the highest mortality near the flower strips. As no effect of buckwheat flower strips on C. aretas parasitism was found, the positive effect they had on A. comariana control stems from unknown mortality factors. As literature indicates that buckwheat for flower strips can augment a more complex suite of natural enemies, one such mortality factor could be a non-consumptive predator and/or parasitoid effect, but this requires further study. If confirmed, buckwheat may be utilized together with a selective food plant, once identified.
[Mh] Termos MeSH primário: Cadeia Alimentar
Magnoliopsida/crescimento & desenvolvimento
Mariposas/fisiologia
Mariposas/parasitologia
Controle Biológico de Vetores/métodos
Vespas/fisiologia
[Mh] Termos MeSH secundário: Anethum graveolens/crescimento & desenvolvimento
Animais
Borago/crescimento & desenvolvimento
Dinamarca
Fagopyrum/crescimento & desenvolvimento
Feminino
Flores/crescimento & desenvolvimento
Fragaria/crescimento & desenvolvimento
Fungos/fisiologia
Hydrophyllaceae/crescimento & desenvolvimento
Larva/crescimento & desenvolvimento
Larva/microbiologia
Larva/parasitologia
Larva/fisiologia
Longevidade
Masculino
Mariposas/crescimento & desenvolvimento
Mariposas/microbiologia
Óvulo/crescimento & desenvolvimento
Óvulo/parasitologia
Óvulo/fisiologia
Pupa/crescimento & desenvolvimento
Pupa/parasitologia
Pupa/fisiologia
Vespas/crescimento & desenvolvimento
[Pt] Tipo de publicação:EVALUATION STUDIES; JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Em] Mês de entrada:1406
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:140418
[St] Status:MEDLINE
[do] DOI:10.1673/031.013.10401


  4 / 16 MEDLINE  
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[PMID]:22975286
[Au] Autor:Garza-Caligaris LE; Avendaño-Vázquez AO; Alvarado-López S; Zúñiga-Sánchez E; Orozco-Segovia A; Pérez-Ruíz RV; Gamboa-Debuen A
[Ad] Endereço:Instituto de Ecología, Universidad Nacional Autónoma de México, Apartado Postal 70-275, Ciudad Universitaria 04510, México, DF México. agamboa@ecologia.unam.mx
[Ti] Título:At3g08030 transcript: a molecular marker of seed ageing.
[So] Source:Ann Bot;110(6):1253-60, 2012 Nov.
[Is] ISSN:1095-8290
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:BACKGROUND AND AIMS: Prolonged storage generally reduces seed viability and vigour, although the rate of deterioration varies among species and environmental conditions. Here, we suggest a possible ageing molecular marker: At3g08030 mRNA. At3g08030 is a member of the DUF642 highly conserved family of cell-wall-associated proteins that is specific for spermatophytes. METHODS: At3g08030 expression was performed by RT-PCR and qRT-PCR analysis in seed samples differing in their rate of germination and final germination following a matrix priming and/or controlled deterioration (rapid ageing) treatment. KEY RESULTS: The At3g08030 gene transcript was present during the entire Arabidopsis thaliana plant life cycle and in seeds, during maturation, the ripening period and after germination. Matrix priming treatment increased the rate of germination of control seeds and seeds aged by controlled deterioration. Priming treatments also increased At3g08030 expression. To determine whether the orthologues of this gene are also age markers in other plant species, At3g08030 was cloned in two wild species, Ceiba aesculifolia and Wigandia urens. As in A. thaliana, the At3g08030 transcript was not present in aged seeds of the tested species but was present in recently shed seeds. A reduction in germination performance of the aged seeds under salt stress was determined by germination assays. CONCLUSIONS: At3g08030 mRNA detection in a dry seed lot has potential for use as a molecular marker for germination performance in a variety of plant species.
[Mh] Termos MeSH primário: Proteínas de Arabidopsis/genética
Arabidopsis/genética
Ceiba/genética
Germinação/genética
Hydrophyllaceae/genética
Sementes/genética
[Mh] Termos MeSH secundário: Arabidopsis/efeitos dos fármacos
Arabidopsis/fisiologia
Sequência de Bases
Proteínas de Transporte/genética
Ceiba/efeitos dos fármacos
Ceiba/fisiologia
Flores/genética
Regulação da Expressão Gênica de Plantas
Marcadores Genéticos
Germinação/efeitos dos fármacos
Temperatura Alta
Hydrophyllaceae/efeitos dos fármacos
Hydrophyllaceae/fisiologia
Dados de Sequência Molecular
Folhas de Planta/genética
RNA Mensageiro/genética
RNA de Plantas/genética
Reação em Cadeia da Polimerase em Tempo Real
Plântulas/genética
Sementes/efeitos dos fármacos
Sementes/fisiologia
Alinhamento de Sequência
Cloreto de Sódio/farmacologia
Fatores de Tempo
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Arabidopsis Proteins); 0 (At3g08030 protein, Arabidopsis); 0 (Carrier Proteins); 0 (Genetic Markers); 0 (RNA, Messenger); 0 (RNA, Plant); 451W47IQ8X (Sodium Chloride)
[Em] Mês de entrada:1304
[Cu] Atualização por classe:170220
[Lr] Data última revisão:
170220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:120915
[St] Status:MEDLINE
[do] DOI:10.1093/aob/mcs200


  5 / 16 MEDLINE  
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[PMID]:22225610
[Au] Autor:Tiryaki I; Keles H
[Ad] Endereço:Kahramanmaras Sutcu Imam University, Faculty of Agriculture, Department of Field Crops, Kahramanmaras, Turkey. itiryaki@ksu.edu.tr
[Ti] Título:Reversal of the inhibitory effect of light and high temperature on germination of Phacelia tanacetifolia seeds by melatonin.
[So] Source:J Pineal Res;52(3):332-9, 2012 Apr.
[Is] ISSN:1600-079X
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Possible role of melatonin in the germination of negatively photoblastic and thermosensitive seeds of Phacelia tanacetifolia Benth was studied. Final germination percentage (FGP) was determined in the presence or absence of light at various temperatures, ranging from 0 to 40°C. The highest FGP was determined as 48.7% and 92% at temperature of 15°C in the presence and absence of light, respectively. Seeds were primed with 1% KNO(3) containing various concentrations (0.3, 1, 6, 12, 30, 60, or 90 µM) of melatonin for 2 days at 15°C in darkness. Primed seeds were germinated at an inhibitory temperature of 30°C, and results were compared to those occurring at the optimum temperature of 15°C under both light and no light conditions. Melatonin incorporated into priming medium significantly reversed the inhibitory effects of light and high temperature. Germination was elevated from 2.5% to 52% of FGP for seeds primed in the presence of 6 µM melatonin in darkness at 30°C, while 1 µM melatonin had the highest FGP (21.0%) in the presence of light at 30°C. The highest FGP (47.5%) was obtained from seeds primed in the presence of 0.3 µM melatonin under the light condition at 15°C, while untreated seeds had 1.5% of FGP. The fastest seed germination was determined from seeds primed in the presence of 0.3 µM melatonin (G(50) = 0.56 days) at 15°C in darkness. The possible roles of melatonin in promoting germination parameters of photo- and thermosensitive seed germination are discussed.
[Mh] Termos MeSH primário: Germinação/fisiologia
Temperatura Alta
Hydrophyllaceae/embriologia
Luz
Sementes/fisiologia
[Mh] Termos MeSH secundário: Escuridão
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Em] Mês de entrada:1207
[Cu] Atualização por classe:120320
[Lr] Data última revisão:
120320
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:120110
[St] Status:MEDLINE
[do] DOI:10.1111/j.1600-079X.2011.00947.x


  6 / 16 MEDLINE  
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[PMID]:22352163
[Au] Autor:Levine JM; McEachern AK; Cowan C
[Ad] Endereço:Department of Ecology, Evolution and Marine Biology, University of California, Santa Barbara, California 93106, USA. jlevine@ethz.ch
[Ti] Título:Seasonal timing of first rain storms affects rare plant population dynamics.
[So] Source:Ecology;92(12):2236-47, 2011 Dec.
[Is] ISSN:0012-9658
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:A major challenge in forecasting the ecological consequences of climate change is understanding the relative importance of changes to mean conditions vs. changes to discrete climatic events, such as storms, frosts, or droughts. Here we show that the first major storm of the growing season strongly influences the population dynamics of three rare and endangered annual plant species in a coastal California (USA) ecosystem. In a field experiment we used moisture barriers and water addition to manipulate the timing and temperature associated with first major rains of the season. The three focal species showed two- to fivefold variation in per capita population growth rates between the different storm treatments, comparable to variation found in a prior experiment imposing eightfold differences in season-long precipitation. Variation in germination was a major demographic driver of how two of three species responded to the first rains. For one of these species, the timing of the storm was the most critical determinant of its germination, while the other showed enhanced germination with colder storm temperatures. The role of temperature was further supported by laboratory trials showing enhanced germination in cooler treatments. Our work suggests that, because of species-specific cues for demographic transitions such as germination, changes to discrete climate events may be as, if not more, important than changes to season-long variables.
[Mh] Termos MeSH primário: Asteraceae
Espécies em Perigo de Extinção
Germinação
Hydrophyllaceae
Chuvas
[Mh] Termos MeSH secundário: California
Mudança Climática
Dinâmica Populacional
Estações do Ano
Temperatura Ambiente
Fatores de Tempo
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T; RESEARCH SUPPORT, U.S. GOV'T, NON-P.H.S.
[Em] Mês de entrada:1203
[Cu] Atualização por classe:130523
[Lr] Data última revisão:
130523
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:120223
[St] Status:MEDLINE


  7 / 16 MEDLINE  
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[PMID]:21338812
[Au] Autor:Kälber T; Meier JS; Kreuzer M; Leiber F
[Ad] Endereço:ETH Zurich, Institute of Agricultural Sciences, Universitaetsstrasse 2, CH-8092 Zurich, Switzerland.
[Ti] Título:Flowering catch crops used as forage plants for dairy cows: influence on fatty acids and tocopherols in milk.
[So] Source:J Dairy Sci;94(3):1477-89, 2011 Mar.
[Is] ISSN:1525-3198
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The effect of several flowering dicotyledonous catch crop plants (dicots) on milk fat quality in cows was investigated to test the hypothesis that their phenolic compounds may inhibit ruminal biohydrogenation and thus enhance the transfer to milk of intact, plant-derived polyunsaturated fatty acids. Berseem clover (Trifolium alexandrinum), buckwheat (Fagopyrum esculentum), and phacelia (Phacelia tanacetifolia) were sown in mixture with ryegrass (Lolium multiflorum; intended biomass proportion of 0.2) on 1ha. For comparison, nonflowering chicory (Cichorium intybus, also sown in mixture with ryegrass) and pure ryegrass were cultivated. Realized biomass proportions (wet weight) were 91% for berseem clover, 69% for buckwheat, 54% for phacelia, and 51% for chicory. At the start of flowering (or from d 47 after sowing onward), cultures were harvested daily and fed for 20 d ad libitum to groups of 6 midlactation cows each. Additionally, 1 kg each of energy and protein concentrate and pure ryegrass hay were fed. Individual intake and milk yield of the cows were measured daily. Milk samples were obtained twice daily 5 d before and from 11 to 20 d after the start of treatment feeding. Feed samples were drawn twice a week from the fresh feeds. Apart from standard traits, feeds and milk were analyzed for fatty acids, tocopherols, and phenolic fractions. Only a few substantial treatment effects on intake and performance were observed. All diets based on dicots increased α-linolenic acid (ALA) concentrations in milk fat compared with the ryegrass diet even though the corresponding swards were not generally richer in ALA. The highest ALA concentration in milk fat (1.3 g/100g of fatty acids) occurred with the berseem clover diet. Transfer rate of ALA from feed to milk was highest with the buckwheat diet (0.09) and lowest with ryegrass (0.05). This was congruent with the differences in total extractable phenols, being high in the buckwheat sward (2.6% of dry matter) and low in the ryegrass sward (1.2% of dry matter). Intermediates of ALA biohydrogenation were lowest in the milk fat of the buckwheat group, indicating an inhibitory effect of this treatment, which provided the highest dietary levels of phenols. The α-tocopherol concentration in milk was higher with the buckwheat diet than with berseem clover and phacelia diets. The study provides evidence that the ALA concentration in milk fat could be enhanced by feeding flowering dicots; however, this was due to different modes of action.
[Mh] Termos MeSH primário: Bovinos/fisiologia
Fagopyrum/metabolismo
Ácidos Graxos/análise
Hydrophyllaceae/metabolismo
Leite/química
Tocoferóis/análise
Trifolium/metabolismo
[Mh] Termos MeSH secundário: Ração Animal
Fenômenos Fisiológicos da Nutrição Animal
Animais
Bovinos/metabolismo
Chicória/metabolismo
Dieta/veterinária
Feminino
Lactação/fisiologia
Lolium/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE; RANDOMIZED CONTROLLED TRIAL; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Fatty Acids); R0ZB2556P8 (Tocopherols)
[Em] Mês de entrada:1104
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:110223
[St] Status:MEDLINE
[do] DOI:10.3168/jds.2010-3708


  8 / 16 MEDLINE  
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[PMID]:19032498
[Au] Autor:Del Castillo RF; Trujillo S
[Ad] Endereço:CIIDIR Oaxaca, Instituto Politécnico Nacional, Santa Cruz Xoxocotlán, Oaxaca, Mexico. rdelcast@yahoo.com
[Ti] Título:Evidence of restoration cost in the annual gynodioecious Phacelia dubia.
[So] Source:J Evol Biol;22(2):306-13, 2009 Feb.
[Is] ISSN:1420-9101
[Cp] País de publicação:Switzerland
[La] Idioma:eng
[Ab] Resumo:A negative pleiotropic effect on fitness of nuclear sex-determining genes (cost of restoration) could explain nuclear-cytoplasmic gynodioecy but rarely has been demonstrated empirically. In a gynodioecious Phacelia dubia population, maternal lineages produce only hermaphroditic progenies irrespective of the pollen parent (N) or can segregate females (S). Natural progenies of N maternal plants had lower seed viability than that of S. Full-sib progenies of unrelated hermaphrodites from all possible matings between N and S lineages had similar pollen filling but differed in sporophyte performance, mainly at seed germination stage. A discrete multivariate analysis reveals that the performance of N(female symbol) x S(male symbol) progeny at early stages of development was significantly lower than that of the other three types of mating in agreement with the silent-cost-of-restoration hypothesis, affecting the sporophyte. The restoration cost and male sterility appear to be dominant and consequence of nuclear-cytoplasmic incompatibilities that may maintain nuclear-cytoplasmic polymorphism by frequency-dependent selection.
[Mh] Termos MeSH primário: Hydrophyllaceae/fisiologia
[Mh] Termos MeSH secundário: Análise de Variância
Germinação/genética
Hydrophyllaceae/genética
Pólen/fisiologia
Reprodução/fisiologia
Seleção Genética
Análise de Sobrevida
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Em] Mês de entrada:0902
[Cu] Atualização por classe:091119
[Lr] Data última revisão:
091119
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:081127
[St] Status:MEDLINE
[do] DOI:10.1111/j.1420-9101.2008.01644.x


  9 / 16 MEDLINE  
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[PMID]:18657429
[Au] Autor:Uematsu K; Fukui Y
[Ad] Endereço:Department of Applied Biological Chemistry, Laboratory of Biological Chemistry, Graduate School of Agricultural and Life Science, The University of Tokyo, Tokyo, Japan.
[Ti] Título:Role and regulation of cAMP in seed germination of Phacelia tanacetifolia.
[So] Source:Plant Physiol Biochem;46(8-9):768-74, 2008 Aug-Sep.
[Is] ISSN:0981-9428
[Cp] País de publicação:France
[La] Idioma:eng
[Ab] Resumo:Although adenosine 3',5'-cyclic monophosphate (cAMP) is known as a key second messenger in many living organisms, regulating a wide range of cellular responses, its biological function in higher plants is not well understood. In this study, the role and the regulation mechanism of cAMP in seed germination of Phacelia tanacetifolia Benth. were examined. The cAMP level of the seeds incubated under optimal conditions for germination showed a transient elevation before germination. When the seeds were exposed to light or supraoptimal temperature during incubation, elevation of cAMP levels as well as germination of the seeds were inhibited. Addition of membrane-permeable cAMP to the medium restored the germination rates of these seeds, suggesting that cAMP functions during germination. Treatment of the seeds with gibberellin (GA) was also effective to restore the elevation of cAMP levels and germination of the seeds. Uniconazole, a potent inhibitor of GA biosynthesis, blocked elevation of cAMP level under optimal conditions for germination. These results suggest that cAMP plays a role in the regulation of germination and that the cAMP level is regulated by GA in P. tanacetifolia seeds.
[Mh] Termos MeSH primário: AMP Cíclico/metabolismo
Germinação
Hydrophyllaceae/crescimento & desenvolvimento
Sementes/crescimento & desenvolvimento
[Mh] Termos MeSH secundário: Giberelinas/farmacologia
Hydrophyllaceae/efeitos dos fármacos
Hydrophyllaceae/metabolismo
Luz
Sementes/efeitos dos fármacos
Sementes/metabolismo
Temperatura Ambiente
Triazóis/farmacologia
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Gibberellins); 0 (Triazoles); E0399OZS9N (Cyclic AMP); R4ATA06H50 (uniconazole)
[Em] Mês de entrada:0810
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:080729
[St] Status:MEDLINE
[do] DOI:10.1016/j.plaphy.2007.10.015


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[PMID]:18188605
[Au] Autor:McCall AC
[Ad] Endereço:Center for Population Biology, One Shields Avenue, University of California, Davis, CA 95616, USA. mccalla@denison.edu
[Ti] Título:Florivory affects pollinator visitation and female fitness in Nemophila menziesii.
[So] Source:Oecologia;155(4):729-37, 2008 Apr.
[Is] ISSN:0029-8549
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:While herbivory has traditionally been studied as damage to leaves, florivory - herbivory to flowers prior to seed set - can also have large effects on plant fitness. Florivory can decrease fitness directly, either through the destruction of gametes or through alterations to plant physiology during fruit set, and can also change the appearance of a flower, deterring pollinators and reducing seed set. In order to distinguish between these hypotheses, it is necessary to both damage flowers and add pollen in excess to study the effects of damage on pollen limitation. Very few studies have used this technique over the lifetime of a plant. Here I describe a series of experiments showing the effects of natural and artificial damage on reproductive success in the annual plant Nemophila menziesii (Hydrophyllaceae, sensu lato). I show that natural and artificial petal damage decreased radial symmetry relative to controls and that both types of damage deterred pollinator activity. Both naturally damaged flowers and artificially damaged flowers in the field set fewer fruit or seed relative to undamaged control flowers. Finally, in an experiment crossing artificial petal damage with pollen addition, petal damage alone over the lifetime of this plant decreased female fitness, but only after a threshold of damage was reached. The fitness effect appeared to be direct because there was no detectable effect of pollen addition on the relationship between florivory and fitness. This result implies that both damaged and undamaged plants show similar amounts of pollen limitation and suggests that pollinator-mediated effects contributed little to the negative effects of florivory on female fitness. Florivores may thus be an under-appreciated agent of selection in certain plants, although more experimental manipulation of florivory is needed to determine if it is important over a range of taxa.
[Mh] Termos MeSH primário: Abelhas/fisiologia
Flores
Hydrophyllaceae/fisiologia
Polinização/fisiologia
[Mh] Termos MeSH secundário: Animais
Flores/anatomia & histologia
Flores/fisiologia
Folhas de Planta
Pólen
Sementes
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Em] Mês de entrada:0806
[Cu] Atualização por classe:171010
[Lr] Data última revisão:
171010
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:080112
[St] Status:MEDLINE
[do] DOI:10.1007/s00442-007-0934-5



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