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Pollinator guild organization and its consequences for reproduction in three synchronopatric species of Tibouchina (Melastomataceae)

Franco,Ana Maria; Goldenberg,Renato; Varassin,Isabela Galarda
Fonte: Sociedade Brasileira De Entomologia Publicador: Sociedade Brasileira De Entomologia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2011 EN
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Pollinator guild organization and its consequences for reproduction in three synchronopatric species of Tibouchina (Melastomataceae). In co-flowering plant species, pollinator sharing can result in interspecific pollen transfer and fecundity reduction. Competition will be relaxed whenever there is a large amount of initial pollen supply or if each plant species occupies different habitat patches. Reproduction in Tibouchina cerastifolia (Naudin) Cogn., T. clinopodifolia (DC.) Cogn. and T. gracilis (Bonpl.) Cogn. was studied in an area of Atlantic rainforest to examine whether synchronopatry induces time partitioning among pollinator species. Eleven bee species comprised the pollinator guild. Among pollinators, there were overlaps in bee species composition and in flower visitation time. Direct competition for pollen in Tibouchina Aubl. at the study site seems to lead to different activity periods among the bee species, in which Bombus pauloensis Friese,1913 was most active earlier, while the other species were active later in the day. Bombus pauloensis, the largest bee species recorded on Tibouchina flowers, was the most important and efficient pollinator. This species harvested pollen before the other species and had the shortest handling time. The plants reproduced sexually by selfing or outcrossing...

Evidence for pollinator sharing in Mediterranean nectar-mimic orchids: absence of premating barriers?

Cozzolino, Salvatore; Schiestl, Florian P; Müller, Andreas; De Castro, Olga; Nardella, Antonio Marco; Widmer, Alex
Fonte: The Royal Society Publicador: The Royal Society
Tipo: Artigo de Revista Científica
EN
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Pollinator specificity has traditionally been considered the main reproductive isolation mechanism in orchids. Among Mediterranean orchids, however, many species attract and deceive pollinators by mimicking nectar-rewarding plants. To test the extent to which deceptive orchid species share pollinators, we collected and identified hemipollinaria-carrying insects, and used ribosomal sequences to identify the orchid species from which hemipollinaria were removed. We found that social and solitary bees, and also flies, carried hemipollinaria belonging to nine orchid species with different degrees of specialization. In particular, Anacamptis morio, Dactylorhiza romana and Orchis mascula used a large set of pollinator species, whereas others such as Orchis quadripunctata seemed to be pollinated by one pollinator species only. Out of the insects with hemipollinaria, 19% were found to carry hemipollinaria from more than one orchid species, indicating that sympatric food-deceptive orchids can share pollinators. This sharing was apparent even among orchid sister-species, thus revealing an effective overlap in pollinator sets among closely related species. These results suggest varying degrees of pollinator specificity in these orchids, and indicate that pollinator specificity cannot always act as the main isolation mechanism in food-deceptive temperate orchids.

Pollinator shortage and global crop yield: Looking at the whole spectrum of pollinator dependency

Garibaldi, Lucas A; Aizen, Marcelo A; Cunningham, Saul A; Klein, Alexandra M
Fonte: Landes Bioscience Publicador: Landes Bioscience
Tipo: Artigo de Revista Científica
Publicado em //2009 EN
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27.51%
A pollinator decline caused by environmental degradation might be compromising the production of pollinator-dependent crops. In a recent article, we compared 45 year series (1961–2006) in yield, production and cultivated area of pollinator-dependent and nondependent crop around the world. If pollinator shortage is occurring globally, we expected a lower annual growth rate in yield for pollinator-dependent than nondependent crops, but a higher growth in cultivated area to compensate the lower yield. We have found little evidence for the first “yield” prediction but strong evidence for the second “area” prediction. Here, we present an additional analysis to show that the first and second predictions are both supported for crops that vary in dependency levels from nondependent to moderate dependence (i.e., up to 65% average yield reduction without pollinators). However, those crops for which animal pollination is essential (i.e., 95% average yield reduction without pollinators) showed higher growth in yield and lower expansion in area than expected in a pollination shortage scenario. We propose that pollination management for highly pollinator-dependent crops, such us renting hives or hand pollination, might have compensated for pollinator limitation of yield.

Floral symmetry: pollinator-mediated stabilizing selection on flower size in bilateral species

Gong, Yan-Bing; Huang, Shuang-Quan
Fonte: The Royal Society Publicador: The Royal Society
Tipo: Artigo de Revista Científica
EN
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27.47%
Pollinator-mediated stabilizing selection (PMSS) has been proposed as the driver of the evolutionary shift from radial to bilateral symmetry of flowers. Studies have shown that variation in flower size is lower in bilateral than in radial species, but whether bilateral flowers experience more stabilizing selection pressures by employing fewer, more specialized pollinators than radial flowers remains unclear. To test the PMSS hypothesis, we investigate plant–pollinator interactions from a whole community in an alpine meadow in Hengduan Mountains, China, to examine: (i) variance in flower size and level of ecological generalization (pollinator diversity calculated using functional groups) in 14 bilateral and 13 radial species and (ii) the role pollinator diversity played in explaining the difference of variance in flower size between bilateral and radial species. Our data showed that bilateral species had less variance in flower size and were visited by fewer pollinator groups. Pollinator diversity accounted for up to 40 per cent of the difference in variance in flower size between bilateral and radial species. The mediator effect of pollinator diversity on the relationship between floral symmetry and variance in flower size in the community is consistent with the PMSS hypothesis.

Diverse pollinator communities enhance plant reproductive success

Albrecht, Matthias; Schmid, Bernhard; Hautier, Yann; Müller, Christine B.
Fonte: The Royal Society Publicador: The Royal Society
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
27.51%
Understanding the functional consequences of biodiversity loss is a major goal of ecology. Animal-mediated pollination is an essential ecosystem function and service provided to mankind. However, little is known how pollinator diversity could affect pollination services. Using a substitutive design, we experimentally manipulated functional group (FG) and species richness of pollinator communities to investigate their consequences on the reproductive success of an obligate out-crossing model plant species, Raphanus sativus. Both fruit and seed set increased with pollinator FG richness. Furthermore, seed set increased with species richness in pollinator communities composed of a single FG. However, in multiple-FG communities, highest species richness resulted in slightly reduced pollination services compared with intermediate species richness. Our analysis indicates that the presence of social bees, which showed roughly four times higher visitation rates than solitary bees or hoverflies, was an important factor contributing to the positive pollinator diversity–pollination service relationship, in particular, for fruit set. Visitation rate at different daytimes, and less so among flower heights, varied among social bees, solitary bees and hoverflies...

Single pollinator species losses reduce floral fidelity and plant reproductive function

Brosi, Berry J.; Briggs, Heather M.
Fonte: National Academy of Sciences Publicador: National Academy of Sciences
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
27.47%
Understanding the functional impacts of pollinator species losses on plant populations is critical given ongoing pollinator declines. Simulation models of pollination networks suggest that plant communities will be resilient to losing many or even most of the pollinator species in an ecosystem. These predictions, however, have not been tested empirically and implicitly assume that pollination efficacy is unaffected by interactions with interspecific competitors. By contrast, ecological theory and data from a wide range of ecosystems show that interspecific competition can drive variation in ecological specialization over short timescales via behavioral or morphological plasticity, although the potential implications of such changes in specialization for ecosystem functioning remain unexplored. We conducted manipulative field experiments in which we temporarily removed single pollinator species from study plots in subalpine meadows, to test the hypothesis that interactions between pollinator species can shape individual species’ functional roles via changes in foraging specialization. We show that loss of a single pollinator species reduces floral fidelity (short-term specialization) in the remaining pollinators, with significant implications for ecosystem functioning in terms of reduced plant reproduction...

The Importance of Pollinator Generalization and Abundance for the Reproductive Success of a Generalist Plant

Maldonado, María Belén; Lomáscolo, Silvia Beatriz; Vázquez, Diego Pedro
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 07/10/2013 EN
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Previous studies have examined separately how pollinator generalization and abundance influence plant reproductive success, but none so far has evaluated simultaneously the relative importance of these pollinator attributes. Here we evaluated the extent to which pollinator generalization and abundance influence plant reproductive success per visit and at the population level on a generalist plant, Opuntia sulphurea (Cactaceae). We used field experiments and path analysis to evaluate whether the per-visit effect is determined by the pollinator’s degree of generalization, and whether the population level effect (pollinator impact) is determined by the pollinator’s degree of generalization and abundance. Based on the models we tested, we concluded that the per-visit effect of a pollinator on plant reproduction was not determined by the pollinators’ degree of generalization, while the population-level impact of a pollinator on plant reproduction was mainly determined by the pollinators’ degree of generalization. Thus, generalist pollinators have the greatest species impact on pollination and reproductive success of O. sulphurea. According to our analysis this greatest impact of generalist pollinators may be partly explained by pollinator abundance. However...

Modeling the two-locus architecture of divergent pollinator adaptation: how variation in SAD paralogs affects fitness and evolutionary divergence in sexually deceptive orchids

Xu, Shuqing; Schlüter, Philipp M
Fonte: BlackWell Publishing Ltd Publicador: BlackWell Publishing Ltd
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
27.47%
Divergent selection by pollinators can bring about strong reproductive isolation via changes at few genes of large effect. This has recently been demonstrated in sexually deceptive orchids, where studies (1) quantified the strength of reproductive isolation in the field; (2) identified genes that appear to be causal for reproductive isolation; and (3) demonstrated selection by analysis of natural variation in gene sequence and expression. In a group of closely related Ophrys orchids, specific floral scent components, namely n-alkenes, are the key floral traits that control specific pollinator attraction by chemical mimicry of insect sex pheromones. The genetic basis of species-specific differences in alkene production mainly lies in two biosynthetic genes encoding stearoyl–acyl carrier protein desaturases (SAD) that are associated with floral scent variation and reproductive isolation between closely related species, and evolve under pollinator-mediated selection. However, the implications of this genetic architecture of key floral traits on the evolutionary processes of pollinator adaptation and speciation in this plant group remain unclear. Here, we expand on these recent findings to model scenarios of adaptive evolutionary change at SAD2 and SAD5...

The Robustness of Plant-Pollinator Assemblages: Linking Plant Interaction Patterns and Sensitivity to Pollinator Loss

Astegiano, Julia; Massol, François; Vidal, Mariana Morais; Cheptou, Pierre-Olivier; Guimarães, Paulo R.
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 03/02/2015 EN
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27.56%
Most flowering plants depend on pollinators to reproduce. Thus, evaluating the robustness of plant-pollinator assemblages to species loss is a major concern. How species interaction patterns are related to species sensitivity to partner loss may influence the robustness of plant-pollinator assemblages. In plants, both reproductive dependence on pollinators (breeding system) and dispersal ability may modulate plant sensitivity to pollinator loss. For instance, species with strong dependence (e.g. dioecious species) and low dispersal (e.g. seeds dispersed by gravity) may be the most sensitive to pollinator loss. We compared the interaction patterns of plants differing in dependence on pollinators and dispersal ability in a meta-dataset comprising 192 plant species from 13 plant-pollinator networks. In addition, network robustness was compared under different scenarios representing sequences of plant extinctions associated with plant sensitivity to pollinator loss. Species with different dependence on pollinators and dispersal ability showed similar levels of generalization. Although plants with low dispersal ability interacted with more generalized pollinators, low-dispersal plants with strong dependence on pollinators (i.e. the most sensitive to pollinator loss) interacted with more particular sets of pollinators (i.e. shared a low proportion of pollinators with other plants). Only two assemblages showed lower robustness under the scenario considering plant generalization...

Mating patterns and pollinator mobility are critical traits in forest fragmentation genetics

Breed, M.; Ottewell, K.; Gardner, M.; Marklund, M.; Dormontt, E.; Lowe, A.
Fonte: Nature Publishing Group Publicador: Nature Publishing Group
Tipo: Artigo de Revista Científica
Publicado em //2015 EN
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37.19%
Most woody plants are animal-pollinated, but the global problem of habitat fragmentation is changing the pollination dynamics. Consequently, the genetic diversity and fitness of the progeny of animal-pollinated woody plants sired in fragmented landscapes tend to decline due to shifts in plant-mating patterns (for example, reduced outcrossing rate, pollen diversity). However, the magnitude of this mating-pattern shift should theoretically be a function of pollinator mobility. We first test this hypothesis by exploring the mating patterns of three ecologically divergent eucalypts sampled across a habitat fragmentation gradient in southern Australia. We demonstrate increased selfing and decreased pollen diversity with increased fragmentation for two small-insect-pollinated eucalypts, but no such relationship for the mobile-bird-pollinated eucalypt. In a meta-analysis, we then show that fragmentation generally does increase selfing rates and decrease pollen diversity, and that more mobile pollinators tended to dampen these mating-pattern shifts. Together, our findings support the premise that variation in pollinator form contributes to the diversity of mating-pattern responses to habitat fragmentation.; MF Breed, KM Ottewell, MG Gardner...

The Genetic Basis of Pollinator Adaptation in a Sexually Deceptive Orchid

Xu, Shuqing; Schlüter, Philipp M.; Grossniklaus, Ueli; Schiestl, Florian P.
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
27.47%
In plants, pollinator adaptation is considered to be a major driving force for floral diversification and speciation. However, the genetic basis of pollinator adaptation is poorly understood. The orchid genus Ophrys mimics its pollinators' mating signals and is pollinated by male insects during mating attempts. In many species of this genus, chemical mimicry of the pollinators' pheromones, especially of alkenes with different double-bond positions, plays a key role for specific pollinator attraction. Thus, different alkenes produced in different species are probably a consequence of pollinator adaptation. In this study, we identify genes that are likely involved in alkene biosynthesis, encoding stearoyl-acyl carrier protein (ACP) desaturases (SAD), in three closely related Ophrys species, O. garganica, O. sphegodes, and O. exaltata. Combining floral odor and gene expression analyses, two SAD homologs (SAD1/2) showed significant association with the production of (Z)-9- and (Z)-12-alkenes that were abundant in O. garganica and O. sphegodes, supporting previous biochemical data. In contrast, two other newly identified homologs (SAD5/6) were significantly associated with (Z)-7-alkenes that were highly abundant only in O. exaltata. Both molecular evolutionary analyses and pollinator preference tests suggest that the alkenes associated with SAD1/2 and SAD5/6 are under pollinator-mediated divergent selection among species. The expression patterns of these genes in F1 hybrids indicate that species-specific expression differences in SAD1/2 are likely due to cis-regulation...

Changes in pollinator fauna affect altitudinal variation of floral size in a bumblebee-pollinated herb

Nagano, Yusuke; Abe, Kota; Kitazawa, Tomoaki; Hattori, Mitsuru; Hirao, Akira S; Itino, Takao
Fonte: Blackwell Publishing Ltd Publicador: Blackwell Publishing Ltd
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
27.47%
Geographic trait variations are often caused by locally different selection regimes. As a steep environmental cline along altitude strongly influences adaptive traits, mountain ecosystems are ideal for exploring adaptive differentiation over short distances. We investigated altitudinal floral size variation of Campanula punctata var. hondoensis in 12 populations in three mountain regions of central Japan to test whether the altitudinal floral size variation was correlated with the size of the local bumblebee pollinator and to assess whether floral size was selected for by pollinator size. We found apparent geographic variations in pollinator assemblages along altitude, which consequently produced a geographic change in pollinator size. Similarly, we found altitudinal changes in floral size, which proved to be correlated with the local pollinator size, but not with altitude itself. Furthermore, pollen removal from flower styles onto bees (plant's male fitness) was strongly influenced by the size match between flower style length and pollinator mouthpart length. These results strongly suggest that C. punctata floral size is under pollinator-mediated selection and that a geographic mosaic of locally adapted C. punctata exists at fine spatial scale.

The importance of pollinator generalization and abundance for the reproductive success of a generalist plant

Maldonado, María Belén; Lomascolo, Silvia Beatriz; Vazquez, Diego P.
Fonte: Public Library Science Publicador: Public Library Science
Tipo: info:eu-repo/semantics/article; info:ar-repo/semantics/artículo; info:eu-repo/semantics/publishedVersion Formato: application/pdf
ENG
Relevância na Pesquisa
27.59%
Previous studies have examined separately how pollinator generalization and abundance influence plant reproductive success, but none so far has evaluated simultaneously the relative importance of these pollinator attributes. Here we evaluated the extent to which pollinator generalization and abundance influence plant reproductive success per visit and at the population level on a generalist plant, Opuntia sulphurea (Cactaceae). We used field experiments and path analysis to evaluate whether the per-visit effect is determined by the pollinator?s degree of generalization, and whether the population level effect (pollinator impact) is determined by the pollinator?s degree of generalization and abundance. Based on the models we tested, we concluded that the per-visit effect of a pollinator on plant reproduction was not determined by the pollinators? degree of generalization, while the population-level impact of a pollinator on plant reproduction was mainly determined by the pollinators? degree of generalization. Thus, generalist pollinators have the greatest species impact on pollination and reproductive success of O. sulphurea. According to our analysis this greatest impact of generalist pollinators may be partly explained by pollinator abundance. However...

Interacciones planta-polinizador desde la perspectiva de los polinizadores: diversidad floral, reproducción de abejas solitarias y su especialización; Plant-pollinator interactions from the pollinator´s perspective: floral diversity, solitary bee reproduction and its specialization

Dorado, Jimena
Fonte: Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires Publicador: Facultad de Ciencias Exactas y Naturales. Universidad de Buenos Aires
Tipo: info:eu-repo/semantics/doctoralThesis; tesis doctoral; info:eu-repo/semantics/publishedVersion Formato: application/pdf
Publicado em //2011 SPA
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37.29%
La mayoría de los estudios planta-polinizador se centran en las plantas; en esta tesis fueron estudiadas desde la perspectiva de los polinizadores. Primero se evaluó la relación diversidadestabilidad para la producción floral como recurso para los polinizadores a lo largo de una temporada de floración. Los resultados mostraron una relación positiva que permite evaluar la generalidad de esta relación. Además, se evaluó el efecto de medidas ecológicas simples y comúnmente utilizadas, como la diversidad y abundancia floral, sobre el éxito reproductivo de los polinizadores, obteniéndose una respuesta especie específica. Existen dos mecanismos que explican la ampliación del nicho poblacional, pero solo uno de ellos ha sido evaluado proponiendose como el mecanismo general. Aquí, se evaluaron ambos mecanismos sobre varias especies de abeja con resultados diferentes a los reportados previamente, ya que ambos mecanismos operan. Por último, se evaluó cuán confiables son las inferencias sobre las especies raras en las redes planta-polinizador ya que podrían estar sesgadas por el tipo de muestreo utilizado para construirlas. Este estudio demostró que el sesgo existe y que aumenta con la rareza de las especies. Esta tesis permitió avanzar en el conocimiento de las interacciones planta-polinizador...

Floral integration and pollinator diversity in the generalized plant-pollinator system of Alstroemeria ligtu (Alstroemeriaceae)

Pérez, Fernanda; Murúa, Maureen M.; González, Alejandra V.
Fonte: Springer Publicador: Springer
Tipo: Artículo de revista
EN
Relevância na Pesquisa
27.54%
Articulo de publicacion SCOPUS; Floral integration may result from the combined effects of pollinator-mediated selection, genetic correlations and abiotic factors. Thus, by sampling a set of populations in the field and examining their variation of floral correlations in relation to pollinators and abiotic factors, we intended to shed light on the ecological factors underlying the evolution of floral integration. In this study, floral integration patterns and the composition of pollinator assemblage were characterized across ten populations of Alstroemeria ligtu to test the following: (1) Whether the patterns of floral integration estimated at population level covary with the composition of local pollinator assemblage, climate and/or geographic distance. (2) Whether the magnitude of floral integration decreases with the number or the morphological variability of pollinators. (3) Whether the behavior of the three most widespread pollinators is affected by floral integration. Our results indicated that populations with similar patterns of integration showed greater similitude in pollinator assemblages, but that this was not related to climate or geographic distance. We also found that the most widespread pollinator, Centris nigerrima...

Is floral diversification associated with pollinator divergence? Flower shape, flower colour and pollinator preference in chilean Mimulus

Carvallo, Gastón; Willis, J. H.; Cooley, A. M.
Fonte: OXFORD UNIV PRESS Publicador: OXFORD UNIV PRESS
Tipo: Artículo de revista
EN
Relevância na Pesquisa
27.51%
Background and Aims Adaptation to different pollinators is thought to drive divergence in flower colour and morphology, and may lead to interspecific reproductive isolation. Floral diversity was tested for association with divergent pollinator preferences in a group of four closely related wildflower species: the yellow-flowered Mimulus luteus var. luteus and the red-pigmented M. l. variegatus, M. naiandinus and M. cupreus. Methods Patterns of pollinator visitation were evaluated in natural plant populations in central Chile, including both single-species and mixed-species sites. Floral anthocyanin pigments were identified, and floral morphology and nectar variation were quantified in a common garden experiment using seeds collected from the study sites. Key Results Mimulus l. luteus, M. l. variegatus and M. naiandinus are morphologically similar and share a single generalist bumblebee pollinator, Bombus dahlbomii. Mimulus cupreus differs significantly from the first three taxa in corolla shape as well as nectar characteristics, and had far fewer pollinator visits. Conclusions This system shows limited potential for pollinator-mediated restriction of gene flow as a function of flower colour, and no evidence of transition to a novel pollinator. Mimulus cupreus may experience reduced interspecific gene flow due to a lack of bumblebee visitation...

Relationship between floral colour and pollinator composition in four plant communities

Reverté Saiz, Sara; Bosch Gras, Jordi; Retana Alumbreros, Javier
Fonte: Universidade Autônoma de Barcelona Publicador: Universidade Autônoma de Barcelona
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em //2014 ENG
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27.47%
Pollinators use a variety of floral cues to locate resources, but the relative importance of these different cues on pollinator foraging decisions is unclear. However, floral colour is undoubtedly one of the most important, as evidenced in previous works revealing the importance of floral colour on pollinator choices and determining flower visitor composition. Our purpose is to establish whether there is a relationship between flower colour and pollinator composition in natural communities. We measured the floral reflectance spectrum of 109 plant populations, from 300 to 700 nm, and divided it in four broad bands of 100 nm each. We found a phylogenetic signal on floral colour variables, and considered this in our analyses. Our results show a lack of concordance between colour spectra and pollinator assemblages. Nevertheless, this work proves that colour determines plant-pollinator relationships in some degree. Thus, particular pollinator groups display preferences for certain bands of the colour spectrum. These preferences match those expected from the pollination syndromes theory. Future work on this issue should combine floral colour along with other floral traits, to assess the importance of the combination of the main floral features for determining pollinator attraction and behaviour together.

The role of floral traits in structuring plant-pollinator interactions

Primante, Clara
Fonte: [Barcelona] : Universitat Autònoma de Barcelona, Publicador: [Barcelona] : Universitat Autònoma de Barcelona,
Tipo: Tesis i dissertacions electròniques; info:eu-repo/semantics/doctoralThesis; info:eu-repo/semantics/publishedVersion Formato: application/pdf
Publicado em //2015 ENG
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37.54%
Les interaccions planta-pol·linitzador són un component essencial de la biodiversitat i la funció ecològica dels ecosistemes terrestres. Un dels principals objectius de l'ecologia de la pol·linització és descriure aquestes interaccions i comprendre els factors subjacents a la seva estructura. En aquesta tesi doctoral es presenten els resultats dels estudis duts a terme durant tres anys en una comunitat mediterrània de plantes i els seus insectes pol·linitzadors al parc natural del Garraf (NE Espanya). En el capítol 1 es van registrar les interaccions planta-pol·linitzador i es van mesurar diferents trets morfològics, fenològics i ecològics de les especies de plantes i pol·linitzadors en un intent d'establir quins d'aquest trets estructuren les relacions planta-pol·linitzador. Es van registrar 14.713 contactes entre les principals 23 espècies de plantes i 221 espècies de pol·linitzadors, que van representar 960 interaccions específiques. Trobem que un tret ecològic (densitat de flors) i un tret fenològic (temps de floració) de les plantes van ser els principals factors que expliquen les interaccions observades. Trets florals, com la restricció de la corol·la i el pol·len i la producció de nèctar per flor...

Stakeholder Analysis for Monarch Butterfly and Pollinator Conservation in Oakland County Parks

Appel, Lisa
Fonte: Universidade Duke Publicador: Universidade Duke
Tipo: Masters' project
Publicado em 24/04/2015
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37.54%
The North American Monarch butterfly (Danaus plexippus) population has declined by 90% in the last twenty years. Scientists cite a number of factors for their decrease, including changing pesticide use, weather, and habitat loss. In December 2014, the negative trend prompted the United States Fish and Wildlife Service to initiate a status review of the Monarch butterfly under the Endangered Species Act. Given their relatively large land-holdings in developed landscapes, parklands could serve as important habitat for Monarch butterflies and other pollinators. Park management and interpretive strategies can help shape public attitudes about the environment. This study uses stakeholder analysis to research perceptions and priorities for addressing pollinator conservation at Oakland County Parks and Recreation (OCPR). OCPR manages 13 parks encompassing 6,701 acres, including 3,146 acres of natural areas in southeastern Michigan. This research answers the following questions to assist OCPR in implementing conservation actions that appropriately engage internal and external stakeholders. 1. Who are the stakeholders involved with Monarch butterfly and pollinator conservation in Oakland County? 2. What is the extent of current Monarch butterfly and pollinator conservation both internally and externally? 3. What are external stakeholder perceptions for OCPR’s priorities in Monarch butterfly and pollinator conservation? 4. How can stakeholder values and interests be integrated into program design for an Oakland County pollinator conservation plan? 5. How do local park efforts relate to national conservation programs? The methods section reviews stakeholder theory and its application in natural resource management and program design. Past research indicates that stakeholder actions can be coordinated in ways to maximize the efficacy and efficiency of a system. Through an analytical categorization...

Pollinator attractiveness increases with distance from flowering orchids

Wong, Bob; Salzmann, Charlotte; Schiestl, Florian
Fonte: Royal Society of London Publicador: Royal Society of London
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
37.03%
Orchids are extraordinary among plants because many species are pollinated through sexual duplicity by producing flowers that mimic female insects to lure unsuspecting males. Previous work showed that sexual deception by the orchid Chiloglottis trapeziformis can have a negative impact on its wasp pollinator Neozeleboria cryptoides. We report that female wasps may be capable of mitigating the cost of the orchids' deception. Although male wasps quickly habituated to areas planted with unrewarding flower decoys, we found that the effectiveness of the chemical cue used by the wingless females to attract males increases with increasing distance from an orchid patch. The apparent specificity of the males' site-based avoidance strategy means that females emerging in areas occupied by flowering orchids could, potentially, leave the orchid colony by walking to increase their attractiveness.