998 resultados para fig


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Phonemic codes are accorded a privileged role in most current models of immediate serial recall, although their effects are apparent in short-term proactive interference (PI) effects as well. The present research looks at how assumptions concerning distributed representation and distributed storage involving both semantic and phonemic codes might be operationalized to produce PI in a short-term cued recall task. The four experiments reported here attempted to generate the phonemic characteristics of a nonrhyming, interfering foil from unrelated filler items in the same list. PI was observed when a rhyme of the foil was studied or when the three phonemes of the foil were distributed across three studied filler items. The results suggest that items in short-term memory are stored in terms of feature bundles and that all items are simultaneously available at retrieval.

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Mutualisms, such as the fig-agaonid wasp association, are susceptible to colonization by parasitic species, which exploit the resources involved therein. In most cases, they oviposit into the figs from outside without providing any pollination service. In this study, we used several different methods (adhesive traps and direct standardized field observations) to assess the colonization sequence of a diverse fig wasp fauna associated with Ficus citrifolia, section Americana, in Brazil. They consistently showed a temporal partitioning in colonization among non-pollinating fig wasp species. Idarnes species belonging to the flavicollis and incerta groups colonized figs just before or during the fig receptive phase. In contrast, Idarnes females belonging to the carme group oviposited one to three weeks later, mainly in the middle of the inter-floral phase. Eurytoma, Heterandrium, Physothorax and Torymus were later colonizers, and laid eggs either in the middle or during the late inter-floral phase. The results suggest that these Neotropical fig wasps have different strategies of resource exploitation, even among species belonging to the same genus.

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Males of pollinating and some non-pollinating fig wasps are wingless and quite dissimilar to their co-specific females. Due to the accentuated sexual dimorphism, males and females of some fig wasp species were described in different genera. We used morphological sperm features obtained from male seminal vesicles and female spermathecas to associate sexes in three non-pollinating fig wasp species, genus Idarnes, that are associated with Ficus citrifolia in Brazil. Sperm obtained from each female morph species presented diagnostic features that led to the association with sperm obtained from males. This method can potentially be used to help enlighten taxonomic problems in other wasp species with sexual di- or polymorphism.

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Ficus arpazusa Casaretto is a fig tree native to the Atlantic Rain Forest sensu lato. High levels of genetic diversity and no inbreeding were observed in Ficus arpazusa. This genetic pattern is due to the action of its pollinator, Pegoscapus sp., which disperses pollen an estimated distance of 5.6 km, and of Ficus arpazusa`s mating system which, in the study area, is allogamous. This study highlights the importance of adding both ecological and genetic data into population studies, allowing a better understanding of evolutionary processes and in turn increasing the efficacy of forest management and revegetation projects, as well as species conservation.

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O Brasil é o maior produtor, consumidor e exportador de sementes de espécies forrageiras de clima tropical. Objetivou-se, com este estudo, avaliar o desenvolvimento inicial de Brachiaria dictyoneura cv. Llanero, em função da profundidade de semeadura e dos métodos de superação de dormência. O trabalho foi realizado em casa de vegetação, em blocos casualizados, com quatro repetições e em esquema de parcela subdividida. Os tratamentos aplicados às parcelas foram cinco, com as profundidades de semeadura de 0,0; 2,0; 4,0; 6,0 e 8,0 cm e, nas subparcelas, os métodos de superação da dormência com e sem escarificação. Cada parcela experimental foi constituída de 25 sementes. A partir do 10º dia de semeadura iniciou-se a contagem de plantas emergidas, a fim de se determinar o índice de velocidade de emergência e, aos 35 dias posteriores à semeadura, avaliou-se a emergência das plântulas, a altura de plantas e a matéria seca da parte aérea. As sementes de B. dictioneura semeadas em torno de 4,0 cm de profundidade e submetidas à escarificação mecânica apresentaram melhor desenvolvimento em todos os parâmetros avaliados. A semeadura superficial e aquela em profundidades abaixo de 4,0 cm mostraram-se ineficientes para o desenvolvimento inicial de B. dictioneura.

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The objective of this study was to evaluate the substrate, cuttings collection time, the position and the cutting depth, and the propagation environment on rooting of 'Purple Valinhos' fig tree cuttings in Southwestern Paraná, Brazil. Two experiments were carried out at UTFPR, Câmpus Dois Vizinhos, with hardwoods cuttings from Roxo de Valinhos fig tree. The first experiment used a randomized block design, in 3 x 3 x 2 factorial (substrate x environment x collection time), with four replications of 10 cuttings per plot. The cuttings were collected in the first fifteen days of July and August. The substrates were sand, soil and the mixture of these [1:1 (v / v)]. The environments used were open sky, tunnel with plastic cover and tunnel with half-shade black net cover. The second experiment used a randomized block design, 2 x 2 x 3 factorial (shoot cutting position x soil cover x shoot cutting depth), with four replications of 12 cuttings per plot. In the factor position, the vertically (0 º inclination) and inclined (45 º inclination) shoot cuttings were evaluated. Soil cover was tested with mulching plastic cover or not. The tested depths were 1/3, 1/2 and 2/3 in relation to the total length of the shoot cutting. In both experiments, the following were analyzed: rooting and mortality indices, number of leaves and primary shoots, length of the three largest roots per cutting. It was conclude that, the protected environment with plastic cover on sand as substrate must recommended for the rooting of fig estaca, collecting them in the first half of July. The inclination position and cutting depth of the estaca and the substrate coverage with plastic mulching did not influence the results.

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An understanding of the complex ecological interaction between fig wasps and their host plants in Amazonia requires previous knowledge of their distribution and diversity. The objective of this study was to describe the composition and structure of the wasp community associated with four species of Ficus in the municipal area of Manaus, Amazonas, Brazil. A total of 600 syconia from four species were collected. The study species were: Ficus obtusifolia Kunth; Ficus citrifolia Mill; F. americana subspecies guianensis Desv. form mathewsii; and F. americana subspecies guianensis Desv. form parkeriana. Statistical analyses were used to examine the relationship between fig wasp diversity and syconium diameter, and the effect of non-pollinating wasps on numbers of pollinators and seeds. Forty three species of fig wasp were identified, distributed across seven genera (Pegoscapus, Idarnes, Aepocerus, Physothorax, Anidarnes, Heterandrium , Eurytoma). Idarnes (carme group) was the wasps genus non-pollinator with greatest number of individuals with the greatest number of infested syconia (7409 wasps in 376 syconia). Analysing non-pollinating wasp diversity in relation to fig diameter, a significant difference was observed between the four fig species. Ficus citrifolia and F. americana subspecies guianensis form mathewsii had the smallest diameter but the greatest diversity of fig wasp. Ficus obtusifolia was the only species in which the non-pollinating wasps had a significant negative effect on the number of Pegoscapus sp. and on seed production.

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The objective of this work was to select semivariogram models to estimate the population density of fig fly (Zaprionus indianus; Diptera: Drosophilidae) throughout the year, using ordinary kriging. Nineteen monitoring sites were demarcated in an area of 8,200 m2, cropped with six fruit tree species: persimmon, citrus, fig, guava, apple, and peach. During a 24 month period, 106 weekly evaluations were done in these sites. The average number of adult fig flies captured weekly per trap, during each month, was subjected to the circular, spherical, pentaspherical, exponential, Gaussian, rational quadratic, hole effect, K-Bessel, J-Bessel, and stable semivariogram models, using ordinary kriging interpolation. The models with the best fit were selected by cross-validation. Each data set (months) has a particular spatial dependence structure, which makes it necessary to define specific models of semivariograms in order to enhance the adjustment to the experimental semivariogram. Therefore, it was not possible to determine a standard semivariogram model; instead, six theoretical models were selected: circular, Gaussian, hole effect, K-Bessel, J-Bessel, and stable.

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The survival of micropropagated plants during and after acclimatization is a limiting process to plant establishment. There is little information on how the anatomy of vegetative organs of Ficus carica can be affected by culture conditions and acclimatization. The present research aimed to study the effects of time on culture medium and substrates during the acclimatization of fig tree plantlets produced in vitro, characterizing some leaf anatomy aspects of plantlets cultured in vitro and of fig trees produced in field. Plantlets previously multiplied in vitro were separated and transferred into Wood Plant Medium (WPM) where they were kept for 0, 15, 30, 45 and 60 days. Different substrates were tested and studies on leaf anatomy were performed in order to compare among plantlets grown in vitro, plantlets under 20, 40 and 60 days of acclimatization, and field grown plants. Keeping plantlets for 30 days in WPM allowed better development in Plantmax during acclimatization. Field grown plants presented higher number of stomata, greater epicuticular wax thickness and greater leaf tissue production compared to in vitro ones. The leaf tissues of in vitro plantlets show little differentiation and have great stomata number compared with acclimatized plants, which reduce the number of stomata during the acclimatization process.

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This work aimed to study the effect of drip irrigation management on growth and yield of the 'Roxo de Valinhos' fig tree (Ficus carica L.), at three years old, and to determine crop coefficients (Kc) and its water requirement (ETc) under Baixada Fluminense climate and soil conditions, state of Rio de Janeiro, Brazil. The study was carried out in the experimental area of SIPA (Sistema Integrado de Produção Agroecológica) in Seropédica, Rio de Janeiro State, from July 2011 to May 2012. The experimental area was divided in two blocks, named B1 (sandy clay loam texture) and B2 (loamy sand texture). In each block, irrigation frequencies (IF) of two (T1) and four days (T2) were evaluated, as well as the irrigation absence (T3). Irrigation management and water consumption determination were performed through the soil water balance, using the TDR technique. Plant growth was not affected by IF, differing only in the number of produced internodes. For both soil textures, the mean Kc was 0.60, with a significant difference (p<0.05) only for IF. The estimated mean yield showed no significant differences between both textural classes, ranging from 6,612 kg ha-1 (T3) to 8,554 kg ha-1 (T1). This study indicates the importance of irrigation frequency in the irrigation management of fig trees cultivated in soils with different physical characteristics.

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Food safety management systems (FSMSs) and the scrutinisation of the food safety practices that are intended for adoption on the firm level both offer strategic value to the dried fig sector. This study aims to prove the hypothesis that export orientation is a major motivating force for the adoption of food safety systems in the Turkish dried fig firms. Data were obtained from 91 dried fig firms located in Aydin, Turkey. Interviews were carried out with firms’ managers/owners using a face-to-face questionnaire designed from May to August of 2010. While 36.3 percent of the interviewed firms had adopted one or more systems, the rest had no certification. A binomial logistic econometric model was employed. The parameters that influenced this decision included contractual agreements with other firms, implementation of good practices by the dried fig farmers, export orientation and cost-benefit ratio. Interestingly, the rest of the indicators employed had no statistically significant effect on adoption behaviour. This paper focusses on the export orientation parameter directly in order to test the validity of the main research hypothesis. The estimated marginal effect suggests that when dried fig firms are export-oriented, the probability that these firms will adopt food safety systems goes up by 39.5 percent. This rate was the first range observed among all the marginal probability values obtained and thus verified the hypothesis that export orientation is a major motivator for the adoption of food safety systems in the Turkish dried fig firms.

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There are over 700 species of fig trees in the tropics and several thousand species of fig wasps are associated with their syconia (inflorescences). These wasps comprise a monophyletic family of fig pollinators and several diverse lineages of non-pollinating wasps. The pollinator larvae gall fig flowers, while larvae of non-pollinating species either initiate their own galls or parasitise the galls of other wasps. A single fig species has 1-4 pollinator species and also hosts up to 30 non-pollinating wasp species. Most wasps show a high degree of host plant specificity and are known from only a single fig species. However, in some cases wasps may be shared across closely related fig species. There is impressive morphological coevolution between figs and fig wasps and this, combined with a high degree of partner specificity, led to the expectation that figs and pollinators have cospeciated extensively. Comparison of deep phylogenies supports long-term codivergence of figs and pollinators, but also suggests that some host shifts have occurred. Phylogenies of more closely related species do not match perfectly and may even be incongruent, suggesting significant roles for processes other than strict cospeciation. Combined with recent evidence on host specificity patterns, this suggests that pollinator wasps may often speciate by host shifts between closely related figs, or by duplication (the wasp speciates but the fig doesn't). The frequencies and biological details of these different modes of speciation invite further study. Far less is known about speciation in non-pollinating fig wasps. Some lineages have probably coevolved with figs and pollinators for most of the evolutionary history of the symbiosis, while others appear to be more recent colonisers. Many species appear to be highly host plant specific, but those that lay eggs through the fig wall without entering the syconium (the majority of species) may be subject to fewer constraints on host-shifting than pollinators. There is evidence for substantial host shifting in at least one gens, but also evidence for ecological speciation on the same host plant by niche shifts in other cases. Finally, recent work has begun to address the issue of “community phylogeny” and provided evidence for long-term co-divergence of multiple pollinating and non-pollinating wasp lineages with their host figs.

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We isolated 18 microsatellites from Sycoscapter australis, a nonpollinating fig wasp that develops in figs of Ficus macrophylla, and assessed their variability in 20 wasps. We further optimized nine of these loci for use in three other Sycoscapter species that develop in Ficus rubiginosa figs and assessed their variability in 47-140 wasps per species. These are the first microsatellites developed for nonpollinating fig wasps and show sufficient polymorphism to become important tools in evolutionary and genetical studies of Sycoscapter wasps.