WorldWideScience

Sample records for wind pollination additionally

  1. Wind-Dragged Corolla Enhances Self-Pollination: A New Mechanism of Delayed Self-Pollination

    Science.gov (United States)

    Qu, Rongming; Li, Xiaojie; Luo, Yibo; Dong, Ming; Xu, Huanli; Chen, Xuan; Dafni, Amots

    2007-01-01

    Background and Aims Delayed self-pollination is a mechanism that allows animal-pollinated plants to outcross while ensuring seed production in the absence of pollinators. This study aims to explore a new mechanism of delayed self-pollination facilitated by wind-driven corolla abscission in Incarvillea sinensis var. sinensis. Methods Floral morphology and development, and the process of delayed self-pollination were surveyed. Experiments dealing with pollinator and wind exclusion, pollination manipulations, and pollinator observations were conducted in the field. Key Results Delayed self-pollination occurs when the abscising corolla driven by wind drags the adherent epipetalous stamens, thus leading to contact of anthers with stigma in late anthesis. There is no dichogamy and self-incompatibility in this species. The significantly higher proportion of abscised corolla under natural conditions as compared with that in wind-excluding tents indicates the importance of wind in corolla abscission. When pollinators were excluded, corolla abscission significantly increased the number of pollen grains deposited on the stigma and, as a result, the fruit and seed set. Only half of the flowers in plots were visited by pollinators, and the fruit set of emasculated flowers was significantly lower than that of untreated flowers in open pollination. This species has a sensitive stigma, and its two open stigmatic lobes closed soon after being touched by a pollinator, but always reopened if no or only little pollen was deposited. Conclusions This delayed self-pollination, which involved the movement of floral parts, the active participation of the wind and sensitive stigma, is quite different from that reported previously. This mechanism provides reproductive assurance for this species. The sensitive stigma contributes to ensuring seed production and reducing the interference of selfing with outcrossing. The pollination pattern, which combines actions by bees with indirect

  2. Wind-dragged corolla enhances self-pollination: a new mechanism of delayed self-pollination.

    Science.gov (United States)

    Qu, Rongming; Li, Xiaojie; Luo, Yibo; Dong, Ming; Xu, Huanli; Chen, Xuan; Dafni, Amots

    2007-12-01

    Delayed self-pollination is a mechanism that allows animal-pollinated plants to outcross while ensuring seed production in the absence of pollinators. This study aims to explore a new mechanism of delayed self-pollination facilitated by wind-driven corolla abscission in Incarvillea sinensis var. sinensis. Floral morphology and development, and the process of delayed self-pollination were surveyed. Experiments dealing with pollinator and wind exclusion, pollination manipulations, and pollinator observations were conducted in the field. Delayed self-pollination occurs when the abscising corolla driven by wind drags the adherent epipetalous stamens, thus leading to contact of anthers with stigma in late anthesis. There is no dichogamy and self-incompatibility in this species. The significantly higher proportion of abscised corolla under natural conditions as compared with that in wind-excluding tents indicates the importance of wind in corolla abscission. When pollinators were excluded, corolla abscission significantly increased the number of pollen grains deposited on the stigma and, as a result, the fruit and seed set. Only half of the flowers in plots were visited by pollinators, and the fruit set of emasculated flowers was significantly lower than that of untreated flowers in open pollination. This species has a sensitive stigma, and its two open stigmatic lobes closed soon after being touched by a pollinator, but always reopened if no or only little pollen was deposited. This delayed self-pollination, which involved the movement of floral parts, the active participation of the wind and sensitive stigma, is quite different from that reported previously. This mechanism provides reproductive assurance for this species. The sensitive stigma contributes to ensuring seed production and reducing the interference of selfing with outcrossing. The pollination pattern, which combines actions by bees with indirect participation by wind, is also a new addition to ambophily.

  3. Is Cycas revoluta (Cycadaceae) wind- or insect-pollinated?

    Science.gov (United States)

    Kono, Masumi; Tobe, Hiroshi

    2007-05-01

    Among the Cycadales (Cycadaceae and Zamiaceae), the Zamiaceae are known to be insect-pollinated. In contrast, the Cycadaceae are still considered wind-pollinated, although some doubt has been cast on several species, including Cycas revoluta. Using a large population of C. revoluta on Yonaguni Island (Okinawa, Japan), we performed exclusion experiments, documented insects from male and female cones, and analyzed the morphology of the apical part of the ovule to determine the pollination method of this species. Insect exclusion resulted in a notable reduction in seed set, except in a few individuals growing near male cones. The amount of airborne pollen was abundant within a 2-m radius of male cones but decreased markedly beyond this distance. Pollen grains of C. revoluta were found on the body of Carpophilus chalybeus (Nitidulidae, Coleoptera), one of a few species of insects collected from both male cones and female cones far from males. We conclude that C. revoluta relies on both wind (anemophily) and insect pollination (entomophily), although such anemophily is restricted to female trees growing within a 2-m radius of male trees. The nitidulids are not host specific to this cycad and primarily feed on plant tissue but serve as pollinators during pollen release. Cycas revoluta appears to be in an initial mode of animal pollination, as opposed to the host-specific insect pollination observed in most Zamiaceae.

  4. Wind pollination and propagule formation in Rhizophora mangle L. (Rhizophoraceae: resource or pollination limitation?

    Directory of Open Access Journals (Sweden)

    TARCILA L. NADIA

    2014-03-01

    Full Text Available Rhizophora mangle is considered as a self-compatible mangrove, and is pollinated by wind and insects. However, there is no information about fruit production by autogamy and agamospermy and on the foraging behavior of its flower visitors. Hence, the present study analyzed the pollination and reproductive systems of R. mangle in a mangrove community in northern Pernambuco, Brazil. Floral morphology, sequence of anthesis, and behavior of flower visitors were described; the proportion of flowers that resulted in mature propagules was also recorded. Autogamy, agamospermy, and wind pollination tests were performed, and a new anemophily index is proposed. The flowers of R. mangle are hermaphrodite, protandric, and have high P/O rate. Flies were observed on flowers only during the male phase, probably feeding on mites that consume pollen. Rhizophora mangle is not agamospermic and its fruit production rate by spontaneous self-pollination is low (2.56% compared to wind pollination (19.44%. The anemophily index was high 0.98, and thus it was considered as a good indicator. Only 13.79% of the flowers formed mature propagules. The early stages of fruit development are the most critical and susceptible to predation. Rhizophora mangle is, therefore, exclusively anemophilous in the study area and the propagule dispersal seems to be limited by herbivory.

  5. Aerodynamics of saccate pollen and its implications for wind pollination.

    Science.gov (United States)

    Schwendemann, Andrew B; Wang, George; Mertz, Meredith L; McWilliams, Ryan T; Thatcher, Scott L; Osborn, Jeffrey M

    2007-08-01

    Pollen grains of many wind-pollinated plants contain 1-3 air-filled bladders, or sacci. Sacci are thought to help orient the pollen grain in the pollination droplet. Sacci also increase surface area of the pollen grain, yet add minimal mass, thereby increasing dispersal distance; however, this aerodynamic hypothesis has not been tested in a published study. Using scanning electron and transmission electron microscopy, mathematical modeling, and the saccate pollen of three extant conifers with structurally different pollen grains (Pinus, Falcatifolium, Dacrydium), we developed a computational model to investigate pollen flight. The model calculates terminal settling velocity based on structural characters of the pollen grain, including lengths, widths, and depths of the main body and sacci; angle of saccus rotation; and thicknesses of the saccus wall, endoreticulations, intine, and exine. The settling speeds predicted by the model were empirically validated by stroboscopic photography. This study is the first to quantitatively demonstrate the adaptive significance of sacci for the aerodynamics of wind pollination. Modeling pollen both with and without sacci indicated that sacci can reduce pollen settling speeds, thereby increasing dispersal distance, with the exception of pollen grains having robust endoreticulations and those with thick saccus walls. Furthermore, because the mathematical model is based on structural characters and error propagation methods show that the model yields valid results when sample sizes are small, the flight dynamics of fossil pollen can be investigated. Several fossils were studied, including bisaccate (Pinus, Pteruchus, Caytonanthus), monosaccate (Gothania), and nonsaccate (Monoletes) pollen types.

  6. Static economic dispatch incorporating wind farm using Flower pollination algorithm

    Directory of Open Access Journals (Sweden)

    Suresh Velamuri

    2016-09-01

    Full Text Available Renewable energy is one of the clean and cheapest forms of energy which helps in minimizing the carbon foot print. Due to the less environmental impact and economic issues integration of renewable energy sources with the existing network gained attention. In this paper, the impact of wind energy is analysed in a power system network using static economic dispatch (SED. The wind energy is integrated with the existing thermal systems. Here, the generation scheduling is optimized using Flower pollination algorithm (FPA due to its robustness in solving nonlinear problems. Integration of wind power in the existing system increases the complexity due to its stochastic nature. Weibull distribution function is used for solving the stochastic nature of wind. Scenarios without and with wind power penetration are discussed in detail. The analysis is carried out by considering the losses and installing the wind farm at different locations in the system. The proposed methodology is tested and validated on a standard IEEE 30 bus system.

  7. Turbulence-induced resonance vibrations cause pollen release in wind-pollinated Plantago lanceolata L. (Plantaginaceae).

    Science.gov (United States)

    Timerman, David; Greene, David F; Urzay, Javier; Ackerman, Josef D

    2014-12-06

    In wind pollination, the release of pollen from anthers into airflows determines the quantity and timing of pollen available for pollination. Despite the ecological and evolutionary importance of pollen release, wind-stamen interactions are poorly understood, as are the specific forces that deliver pollen grains into airflows. We present empirical evidence that atmospheric turbulence acts directly on stamens in the cosmopolitan, wind-pollinated weed, Plantago lanceolata, causing resonant vibrations that release episodic bursts of pollen grains. In laboratory experiments, we show that stamens have mechanical properties corresponding to theoretically predicted ranges for turbulence-driven resonant vibrations. The mechanical excitation of stamens at their characteristic resonance frequency caused them to resonate, shedding pollen vigorously. The characteristic natural frequency of the stamens increased over time with each shedding episode due to the reduction in anther mass, which increased the mechanical energy required to trigger subsequent episodes. Field observations of a natural population under turbulent wind conditions were consistent with these laboratory results and demonstrated that pollen is released from resonating stamens excited by small eddies whose turnover periods are similar to the characteristic resonance frequency measured in the laboratory. Turbulence-driven vibration of stamens at resonance may be a primary mechanism for pollen shedding in wind-pollinated angiosperms. The capacity to release pollen in wind can be viewed as a primary factor distinguishing animal- from wind-pollinated plants, and selection on traits such as the damping ratio and flexural rigidity may be of consequence in evolutionary transitions between pollination systems. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  8. Effect of natural inbreeding on variance structure in tests of wind pollination Douglas-fir progenies.

    Science.gov (United States)

    Frank C. Sorensen; T.L. White

    1988-01-01

    Studies of the mating habits of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) have shown that wind-pollination families contain a small proportion of very slow-growing natural inbreds.The effect of these very small trees on means, variances, and variance ratios was evaluated for height and diameter in a 16-year-old plantation by...

  9. Floral trait evolution associated with shifts between insect and wind pollination in the dioecious genus Leucadendron (Proteaceae).

    Science.gov (United States)

    Welsford, Megan R; Hobbhahn, Nina; Midgley, Jeremy J; Johnson, Steven D

    2016-01-01

    Transitions between animal and wind pollination have occurred in many lineages and have been linked to various floral modifications, but these have seldom been assessed in a phylogenetic framework. In the dioecious genus Leucadendron (Proteaceae), transitions from insect to wind pollination have occurred at least four times. Using analyses that controlled for relatedness among Leucadendron species, we investigated how these transitions shaped the evolution of floral structural and signaling traits, including the degree of sexual dimorphism in these traits. Pollen grains of wind-pollinated species were found to be smaller, more numerous, and dispersed more efficiently in wind than were those of insect-pollinated species. Wind-pollinated species also exhibited a reduction in spectral contrast between showy subtending leaves and background foliage, reduced volatile emissions, and a greater degree of sexual dimorphism in color and scent. Uniovulate flowers and inflorescence condensation are conserved ancestral features in Leucadendron and likely served as exaptations in shifts to wind pollination. These results offer insights into the key modifications of male and female floral traits involved in transitions between insect and wind pollination. © 2015 The Author(s). Evolution © 2015 The Society for the Study of Evolution.

  10. A combined model based on CEEMDAN and modified flower pollination algorithm for wind speed forecasting

    International Nuclear Information System (INIS)

    Zhang, Wenyu; Qu, Zongxi; Zhang, Kequan; Mao, Wenqian; Ma, Yining; Fan, Xu

    2017-01-01

    Highlights: • A CEEMDAN-CLSFPA combined model is proposed for short-term wind speed forecasting. • The CEEMDAN technique is used to decompose the original wind speed series. • A modified optimization algorithm-CLSFPA is proposed to optimize the weights of the combined model. • The no negative constraint theory is applied to the combined model. • Robustness of the proposed model is validated by data sampled from four different wind farms. - Abstract: Wind energy, which is stochastic and intermittent by nature, has a significant influence on power system operation, power grid security and market economics. Precise and reliable wind speed prediction is vital for wind farm planning and operational planning for power grids. To improve wind speed forecasting accuracy, a large number of forecasting approaches have been proposed; however, these models typically do not account for the importance of data preprocessing and are limited by the use of individual models. In this paper, a novel combined model – combining complete ensemble empirical mode decomposition adaptive noise (CEEMDAN), flower pollination algorithm with chaotic local search (CLSFPA), five neural networks and no negative constraint theory (NNCT) – is proposed for short-term wind speed forecasting. First, a recent CEEMDAN is employed to divide the original wind speed data into a finite set of IMF components, and then a combined model, based on NNCT, is proposed for forecasting each decomposition signal. To improve the forecasting capacity of the combined model, a modified flower pollination algorithm (FPA) with chaotic local search (CLS) is proposed and employed to determine the optimal weight coefficients of the combined model, and the final prediction values were obtained by reconstructing the refined series. To evaluate the forecasting ability of the proposed combined model, 15-min wind speed data from four wind farms in the eastern coastal areas of China are used. The experimental results of

  11. Reproduction ecology of Pinus halepensis : a monoecious, wind-pollinated and partially serotinous Mediterranean pine tree

    OpenAIRE

    Goubitz, Shirrinka

    2001-01-01

    Fire is an important factor in the evolution and ecology of Mediterranean plant species. The fire frequency has increased in the 20st century. Pines are the most important tree species in the area. Pinus halepensis is the only natural pine in parts of the east Mediterranean basin, such as Israel and Jordan. This pine tree is a monoecious, wind-pollinated tree. Pinus halepensis regenerates in absence of fire as well as after fire, because it is a partially serotinous species. This study aims t...

  12. Gradual disintegration of the floral symmetry gene network is implicated in the evolution of a wind-pollination syndrome

    Science.gov (United States)

    Preston, Jill C.; Martinez, Ciera C.; Hileman, Lena C.

    2011-01-01

    Angiosperms exhibit staggering diversity in floral form, and evolution of floral morphology is often correlated with changes in pollination syndrome. The showy, bilaterally symmetrical flowers of the model species Antirrhinum majus (Plantaginaceae) are highly specialized for bee pollination. In A. majus, CYCLOIDEA (CYC), DICHOTOMA (DICH), RADIALIS (RAD), and DIVARICATA (DIV) specify the development of floral bilateral symmetry. However, it is unclear to what extent evolution of these genes has resulted in flower morphological divergence among closely related members of Plantaginaceae differing in pollination syndrome. We compared floral symmetry genes from insect-pollinated Digitalis purpurea, which has bilaterally symmetrical flowers, with those from closely related Aragoa abietina and wind-pollinated Plantago major, both of which have radially symmetrical flowers. We demonstrate that Plantago, but not Aragoa, species have lost a dorsally expressed CYC-like gene and downstream targets RAD and DIV. Furthermore, the single P. major CYC-like gene is expressed across all regions of the flower, similar to expression of its ortholog in closely related Veronica serpyllifolia. We propose that changes in the expression of duplicated CYC-like genes led to the evolution of radial flower symmetry in Aragoa/Plantago, and that further disintegration of the symmetry gene pathway resulted in the wind-pollination syndrome of Plantago. This model underscores the potential importance of gene loss in the evolution of ecologically important traits. PMID:21282634

  13. Wind gusts and plant aeroelasticity effects on the aerodynamics of pollen shedding: a hypothetical turbulence-initiated wind-pollination mechanism.

    Science.gov (United States)

    Urzay, Javier; Llewellyn Smith, Stefan G; Thompson, Elinor; Glover, Beverley J

    2009-08-21

    Plant reproduction depends on pollen dispersal. For anemophilous (wind-pollinated) species, such as grasses and many trees, shedding pollen from the anther must be accomplished by physical mechanisms. The unknown nature of this process has led to its description as the 'paradox of pollen liberation'. A simple scaling analysis, supported by experimental measurements on typical wind-pollinated plant species, is used to estimate the suitability of previous resolutions of this paradox based on wind-gust aerodynamic models of fungal-spore liberation. According to this scaling analysis, the steady Stokes drag force is found to be large enough to liberate anemophilous pollen grains, and unsteady boundary-layer forces produced by wind gusts are found to be mostly ineffective since the ratio of the characteristic viscous time scale to the inertial time scale of acceleration of the wind stream is a small parameter for typical anemophilous species. A hypothetical model of a stochastic aeroelastic mechanism, initiated by the atmospheric turbulence typical of the micrometeorological conditions in the vicinity of the plant, is proposed to contribute to wind pollination.

  14. Additive Manufacturing of Wind Turbine Molds

    Energy Technology Data Exchange (ETDEWEB)

    Post, Brian [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Richardson, Bradley [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Lloyd, Peter [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Love, Lonnie [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Nolet, Stephen [TPI Composites, Scottsdale, AZ (United States); Hannan, James [TPI Composites, Scottsdale, AZ (United States)

    2017-07-01

    The objective of this project was to explore the utility of Big Area Additive Manufacturing (BAAM) for low cost manufacturing of wind turbine molds. Engineers at Oak Ridge National Laboratory (ORNL) and TPI Composites (TPI) collaborated to design and manufacture a printed mold that can be used for resin infusion of wind turbine components. Specific focus was on required material properties (operating temperatures and pressures, coefficient of thermal expansion (CTE), thermal conductivity), surface finish (accuracy and coatings) and system integration (integrated vacuum ports, and heating element). The project began with a simple proof of principle components, targeting surface coatings and material properties for printing a small section (approximately 4’ x 4’ x 2’) of a mold. Next, the second phase scaled up and integrated with the objective of capturing all of the necessary components (integrated heating to accelerate cure time, and vacuum, sealing) for resin infusion on a mold of significant size (8’ x 20’ x 6’).

  15. The Current State of Additive Manufacturing in Wind Energy Systems

    Energy Technology Data Exchange (ETDEWEB)

    Mann, Margaret [National Renewable Energy Lab. (NREL), Golden, CO (United States); Palmer, Sierra [Worcester Polytechnic Institute (WPI), , Worcester, MA (United States); Lee, Dominic [National Renewable Energy Lab. (NREL), Golden, CO (United States); Kurup, Parthiv [National Renewable Energy Lab. (NREL), Golden, CO (United States); Remo, Timothy [National Renewable Energy Lab. (NREL), Golden, CO (United States); Jenne, Dale Scott [National Renewable Energy Lab. (NREL), Golden, CO (United States); Richardson, Bradley S. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Love, Lonnie J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Post, Brian K. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-12-01

    Wind power is an inexhaustible form of energy that is being captured throughout the U.S. to power the engine of our economy. A robust, domestic wind industry promises to increase U.S. industry growth and competitiveness, strengthen U.S. energy security independence, and promote domestic manufacturing nationwide. As of 2016, ~82GW of wind capacity had been installed, and wind power now provides more than 5.5% of the nation’s electricity and supports more than 100,000 domestic jobs, including 500 manufacturing facilities in 43 States. To reach the U.S. Department of Energy’s (DOE’s) 2015 Wind Vision study scenario of wind power serving 35% of the nation's end-use demand by 2050, significant advances are necessary in all areas of wind technologies and market. An area that can greatly impact the cost and rate of innovation in wind technologies is the use of advanced manufacturing, with one of the most promising areas being additive manufacturing (AM). Considering the tremendous promise offered by advanced manufacturing, it is the purpose of this report to identify the use of AM in the production and operation of wind energy systems. The report has been produced as a collaborative effort for the DOE Wind Energy Technology Office (WETO), between Oak Ridge National Laboratory (ORNL) and the National Renewable Energy Laboratory (NREL).

  16. Pollinator Protection

    Science.gov (United States)

    What the EPA is doing to protect bees and other pollinators from pesticides; including addressing the issue of Colony Collapse Disorder (CCD), risk assessment, decline in pollinator health in general, and why pollinators are important.

  17. Moonlight pollination in the gymnosperm Ephedra (Gnetales).

    Science.gov (United States)

    Rydin, Catarina; Bolinder, Kristina

    2015-04-01

    Most gymnosperms are wind-pollinated, but some are insect-pollinated, and in Ephedra (Gnetales), both wind pollination and insect pollination occur. Little is, however, known about mechanisms and evolution of pollination syndromes in gymnosperms. Based on four seasons of field studies, we show an unexpected correlation between pollination and the phases of the moon in one of our studied species, Ephedra foeminea. It is pollinated by dipterans and lepidopterans, most of them nocturnal, and its pollination coincides with the full moon of July. This may be adaptive in two ways. Many nocturnal insects navigate using the moon. Further, the spectacular reflection of the full-moonlight in the pollination drops is the only apparent means of nocturnal attraction of insects in these plants. In the sympatric but wind-pollinated Ephedra distachya, pollination is not correlated to the full moon but occurs at approximately the same dates every year. The lunar correlation has probably been lost in most species of Ephedra subsequent an evolutionary shift to wind pollination in the clade. When the services of insects are no longer needed for successful pollination, the adaptive value of correlating pollination with the full moon is lost, and conceivably also the trait. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  18. Moonlight pollination in the gymnosperm Ephedra (Gnetales)

    Science.gov (United States)

    Rydin, Catarina; Bolinder, Kristina

    2015-01-01

    Most gymnosperms are wind-pollinated, but some are insect-pollinated, and in Ephedra (Gnetales), both wind pollination and insect pollination occur. Little is, however, known about mechanisms and evolution of pollination syndromes in gymnosperms. Based on four seasons of field studies, we show an unexpected correlation between pollination and the phases of the moon in one of our studied species, Ephedra foeminea. It is pollinated by dipterans and lepidopterans, most of them nocturnal, and its pollination coincides with the full moon of July. This may be adaptive in two ways. Many nocturnal insects navigate using the moon. Further, the spectacular reflection of the full-moonlight in the pollination drops is the only apparent means of nocturnal attraction of insects in these plants. In the sympatric but wind-pollinated Ephedra distachya, pollination is not correlated to the full moon but occurs at approximately the same dates every year. The lunar correlation has probably been lost in most species of Ephedra subsequent an evolutionary shift to wind pollination in the clade. When the services of insects are no longer needed for successful pollination, the adaptive value of correlating pollination with the full moon is lost, and conceivably also the trait. PMID:25832814

  19. ELECTROSTATIC FORCES IN WIND-POLLINATION: PART 1: MEASUREMENT OF THE ELECTROSTATIC CHARGE ON POLLEN

    Science.gov (United States)

    Under fair weather conditions, a weak electric field exists between negative charge induced on the surface of plants and positive charge in the air. This field is magnified around points (e.g. stigmas) and can reach values up to 3x106 V m-1. If wind-disperse...

  20. Diptera, fly pollination, flower visit, mutualism, ecological interaction, alternative pollinators

    Directory of Open Access Journals (Sweden)

    Barbara Gemmill-Herren

    2014-02-01

    Full Text Available While it is well recognised that pollination is an ecosystem service of vital importance to human well-being through its role in food production, it is still remarkable how little is known, on a crop-by-crop basis, about this role, and the extent and causes of declines in the service. Without better documentation of the specific contribution of pollination to crop yields, there have been mounting - and justified - questions about how relevant pollination may be to agricultural development and food security. In addition, the vast majority of studies of pollination services to crops have been carried out in Europe and North America; and certainly the problems we know to impact pollinators most severely – a high dependence on agricultural chemicals and monocropped landscapes offering little diet diversity to pollinators – are typical features of industrialised, Northern hemisphere agriculture.

  1. Biodiversity buffers pollination from changes in environmental conditions.

    Science.gov (United States)

    Brittain, Claire; Kremen, Claire; Klein, Alexandra-Maria

    2013-02-01

    A hypothesized underlying principle of the diversity-functioning relationship is that functional groups respond differently to environmental change. Over 3 years, we investigated how pollinator diversity contributes to the magnitude of pollination service through spatial complementarity and differential response to high winds in California almond orchards. We found honey bees preferentially visited the top sections of the tree. Where wild pollinators were present, they showed spatial complementarity to honey bees and visited the bottom tree sections more frequently. As wind speed increased, honey bees' spatial preference shifted toward the bottom tree sections. In high winds (>2.5 m s(-1) ), orchards with low pollinator diversity (honey bees only) received almost no flower visits. In orchards with high pollinator diversity, visitation decreased to a lesser extent as wild bee visitation was unaffected by high winds. Our results demonstrate how spatial complementarity in diverse communities can help buffer pollination services to environmental changes like wind speed. © 2012 Blackwell Publishing Ltd.

  2. Spatial genetic structure in Milicia excelsa (Moraceae) indicates extensive gene dispersal in a low-density wind-pollinated tropical tree.

    Science.gov (United States)

    Bizoux, J-P; Daïnou, K; Bourland, N; Hardy, O J; Heuertz, M; Mahy, G; Doucet, J-L

    2009-11-01

    In this study, we analysed spatial genetic structure (SGS) patterns and estimated dispersal distances in Milicia excelsa (Welw.) C.C. Berg (Moraceae), a threatened wind-pollinated dioecious African tree, with typically low density (approximately 10 adults/km(2)). Eight microsatellite markers were used to type 287 individuals in four Cameroonian populations characterized by different habitats and tree densities. Differentiation among populations was very low. Two populations in more open habitat did not display any correlation between genetic relatedness and spatial distance between individuals, whereas significant SGS was detected in two populations situated under continuous forest cover. SGS was weak with a maximum S(p)-statistic of 0.006, a value in the lower quartile of SGS estimates for trees in the literature. Using a stepwise approach with Bayesian clustering methods, we demonstrated that SGS resulted from isolation by distance and not colonization by different gene pools. Indirect estimates of gene dispersal distances ranged from sigma(g) = 1 to 7.1 km, one order of magnitude higher than most estimates found in the literature for tropical tree species. This result can largely be explained by life-history traits of the species. Milicia excelsa exhibits a potentially wide-ranging wind-mediated pollen dispersal mechanism as well as very efficient seed dispersal mediated by large frugivorous bats. Estimations of gene flow suggested no major risk of inbreeding because of reduction in population density by exploitation. Different strategy of seed collection may be required for reforestation programmes among populations with different extent of SGS.

  3. Economic value of pollination services on crops in Benin, West Africa

    African Journals Online (AJOL)

    Pollinators provide pollination services that are crucial for sexual reproduction of many flowering plants. Beside wind and water, pollination services are provided by animals but mainly by insects. They improve the quality and the quantity of many crops. This study aimed at accessing the economic value of pollination ...

  4. Spatial and Temporal Trends of Global Pollination Benefit

    Science.gov (United States)

    Lautenbach, Sven; Seppelt, Ralf; Liebscher, Juliane; Dormann, Carsten F.

    2012-01-01

    Pollination is a well-studied and at the same time a threatened ecosystem service. A significant part of global crop production depends on or profits from pollination by animals. Using detailed information on global crop yields of 60 pollination dependent or profiting crops, we provide a map of global pollination benefits on a 5′ by 5′ latitude-longitude grid. The current spatial pattern of pollination benefits is only partly correlated with climate variables and the distribution of cropland. The resulting map of pollination benefits identifies hot spots of pollination benefits at sufficient detail to guide political decisions on where to protect pollination services by investing in structural diversity of land use. Additionally, we investigated the vulnerability of the national economies with respect to potential decline of pollination services as the portion of the (agricultural) economy depending on pollination benefits. While the general dependency of the agricultural economy on pollination seems to be stable from 1993 until 2009, we see increases in producer prices for pollination dependent crops, which we interpret as an early warning signal for a conflict between pollination service and other land uses at the global scale. Our spatially explicit analysis of global pollination benefit points to hot spots for the generation of pollination benefits and can serve as a base for further planning of land use, protection sites and agricultural policies for maintaining pollination services. PMID:22563427

  5. The mechanism of pollination drop withdrawal in Ginkgo biloba L.

    Science.gov (United States)

    Jin, Biao; Zhang, Lei; Lu, Yan; Wang, Di; Jiang, Xiao X; Zhang, Min; Wang, Li

    2012-05-01

    The pollination drop (PD) is a characteristic feature of many wind-pollinated gymnosperms. Although accumulating evidence shows that the PD plays a critical role in the pollination process, the mechanism of PD withdrawal is still unclear. Here, we carefully observed the PD withdrawal process and investigated the underlying mechanism of PD withdrawal, which will aid the understanding of wind-pollination efficiency in gymnosperms. In Ginkgo biloba, PDs were secreted on the micropyle during the pollination period and persisted for about 240 h when not pollinated under laboratory conditions. The withdrawal of an isolated PD required only 1 h for evaporation, much less than a PD on the living ovule, which required 100 h. When pollinated with viable pollen, PDs withdrew rapidly within 4 h. In contrast, nonviable pollen and acetone-treated pollen did not cause PD withdrawal. Although 100% relative humidity significantly inhibited PD withdrawal, pollinated PDs still could withdraw completely within 48 h. Pollen grains of Cycas revoluta, which are similar to those of G. biloba, could induce PD withdrawal more rapidly than those of two distantly related gymnosperms (Pinus thunbergii and Abies firma) or two angiosperms (Paeonia suffruticosa and Orychophragmus violaceus). Furthermore, pollen of G. biloba and C. revoluta submerged immediately when encountering the PD, then sank to the bottom and entered the micropyle. The saccate pollen of P. thunbergii and A. firma submerged into the PD, but remained floating at the top and finally accumulated on the micropyle after PD withdrawal. In contrast, pollen of the angiosperms P. suffruticosa, Salix babylonica, and O. violaceus did not submerge, instead remaining clustered at the edge without entering the PD. We conclude that PD withdrawal is primarily determined by the dynamic balance between evaporation and ovule secretion, of which pollen is a critical stimulator. When conspecific pollen grains were submerged in the PD, ovule

  6. The mechanism of pollination drop withdrawal in Ginkgo biloba L.

    Directory of Open Access Journals (Sweden)

    Jin Biao

    2012-05-01

    Full Text Available Abstract Background The pollination drop (PD is a characteristic feature of many wind-pollinated gymnosperms. Although accumulating evidence shows that the PD plays a critical role in the pollination process, the mechanism of PD withdrawal is still unclear. Here, we carefully observed the PD withdrawal process and investigated the underlying mechanism of PD withdrawal, which will aid the understanding of wind-pollination efficiency in gymnosperms. Results In Ginkgo biloba, PDs were secreted on the micropyle during the pollination period and persisted for about 240 h when not pollinated under laboratory conditions. The withdrawal of an isolated PD required only 1 h for evaporation, much less than a PD on the living ovule, which required 100 h. When pollinated with viable pollen, PDs withdrew rapidly within 4 h. In contrast, nonviable pollen and acetone-treated pollen did not cause PD withdrawal. Although 100% relative humidity significantly inhibited PD withdrawal, pollinated PDs still could withdraw completely within 48 h. Pollen grains of Cycas revoluta, which are similar to those of G. biloba, could induce PD withdrawal more rapidly than those of two distantly related gymnosperms (Pinus thunbergii and Abies firma or two angiosperms (Paeonia suffruticosa and Orychophragmus violaceus. Furthermore, pollen of G. biloba and C. revoluta submerged immediately when encountering the PD, then sank to the bottom and entered the micropyle. The saccate pollen of P. thunbergii and A. firma submerged into the PD, but remained floating at the top and finally accumulated on the micropyle after PD withdrawal. In contrast, pollen of the angiosperms P. suffruticosa, Salix babylonica, and O. violaceus did not submerge, instead remaining clustered at the edge without entering the PD. Conclusions We conclude that PD withdrawal is primarily determined by the dynamic balance between evaporation and ovule secretion, of which pollen is a critical stimulator

  7. Performance ‘S’ Type Savonius Wind Turbine with Variation of Fin Addition on Blade

    Science.gov (United States)

    Pamungkas, S. F.; Wijayanto, D. S.; Saputro, H.; Widiastuti, I.

    2018-01-01

    Wind power has been receiving attention as the new energy resource in addressing the ecological problems of burning fossil fuels. Savonius wind rotor is a vertical axis wind turbines (VAWT) which has relatively simple structure and low operating speed. These characteristics make it suitable for areas with low average wind speed as in Indonesia. To identify the performance of Savonius rotor in generating electrical energy, this research experimentally studied the effect of fin addition for the ‘S’ shape of Savonius VAWT. The fin is added to fill the space in the blade in directing the wind flow. This rotor has two turbine blades, a rotor diameter of 1.1 m and rotor height of 1.4 m, used pulley transmission system with 1:4.2 multiplication ratio, and used a generator type PMG 200 W. The research was conducted during dry season by measuring the wind speed in the afternoon. The average wind speed in the area is 2.3 m/s with the maximum of 4.5 m/s. It was found that additional fin significantly increase the ability of Savonius rotor VAWT to generate electrical energy shown by increasing of electrical power. The highest power generated is 13.40 Watt at a wind speed of 4.5 m/s by adding 1 (one) fin in the blade. It increased by 22.71% from the rotor blade with no additional fin. However, increasing number of fins in the blade was not linearly increase the electrical power generated. The wind rotor blade with 4 additional fins is indicated has the lowest performance, generating only 10.80 Watt electrical power, accounted lower than the one generated by no fin-rotor blade. By knowing the effect of the rotor shape, the rotor dimension, the addition of fin, transmission, and generator used, it is possible to determine alternative geometry design in increasing the electrical power generated by Savonius wind turbine.

  8. Importance of pollinators in changing landscapes for world crops.

    Science.gov (United States)

    Klein, Alexandra-Maria; Vaissière, Bernard E; Cane, James H; Steffan-Dewenter, Ingolf; Cunningham, Saul A; Kremen, Claire; Tscharntke, Teja

    2007-02-07

    The extent of our reliance on animal pollination for world crop production for human food has not previously been evaluated and the previous estimates for countries or continents have seldom used primary data. In this review, we expand the previous estimates using novel primary data from 200 countries and found that fruit, vegetable or seed production from 87 of the leading global food crops is dependent upon animal pollination, while 28 crops do not rely upon animal pollination. However, global production volumes give a contrasting perspective, since 60% of global production comes from crops that do not depend on animal pollination, 35% from crops that depend on pollinators, and 5% are unevaluated. Using all crops traded on the world market and setting aside crops that are solely passively self-pollinated, wind-pollinated or parthenocarpic, we then evaluated the level of dependence on animal-mediated pollination for crops that are directly consumed by humans. We found that pollinators are essential for 13 crops, production is highly pollinator dependent for 30, moderately for 27, slightly for 21, unimportant for 7, and is of unknown significance for the remaining 9. We further evaluated whether local and landscape-wide management for natural pollination services could help to sustain crop diversity and production. Case studies for nine crops on four continents revealed that agricultural intensification jeopardizes wild bee communities and their stabilizing effect on pollination services at the landscape scale.

  9. Pollination Services of Mango Flower Pollinators

    Science.gov (United States)

    Huda, A. Nurul; Salmah, M. R. Che; Hassan, A. Abu; Hamdan, A.; Razak, M. N. Abdul

    2015-01-01

    Measuring wild pollinator services in agricultural production is very important in the context of sustainable management. In this study, we estimated the contribution of native pollinators to mango fruit set production of two mango cultivars Mangifera indica (L). cv. ‘Sala’ and ‘Chok Anan’. Visitation rates of pollinators on mango flowers and number of pollen grains adhering to their bodies determined pollinator efficiency for reproductive success of the crop. Chok Anan failed to produce any fruit set in the absence of pollinators. In natural condition, we found that Sala produced 4.8% fruit set per hermaphrodite flower while Chok Anan produced 3.1% per flower. Hand pollination tremendously increased fruit set of naturally pollinated flower for Sala (>100%), but only 33% for Chok Anan. Pollinator contribution to mango fruit set was estimated at 53% of total fruit set production. Our results highlighted the importance of insect pollinations in mango production. Large size flies Eristalinus spp. and Chrysomya spp. were found to be effective pollen carriers and visited more mango flowers compared with other flower visitors. PMID:26246439

  10. Timing of Bag Application and Removal in Controlled Mass Pollination

    Science.gov (United States)

    F.E. Bridgwater; D.L. Bramlett; V.D. Hipkins

    1999-01-01

    Controlled mass pollination (CMP) among outstanding parents is one way to increase genetic gains from traditional wind-pollinated seed orchards, but the economic success of CMP depends on both genetic gains and costs. CMP has been shown. to be cost-effective (Bridgwater et al. 1998) even when costs were adjusted for risk (Byram and Bridgwater 1999, These Proceedings...

  11. A preliminary synthesis of pollination biology in the Cape flora

    CSIR Research Space (South Africa)

    Rebelo, AG

    1987-01-01

    Full Text Available biology are covered. Chapters reviewing plant breeding systems, insect, bird, mammal and wind pollination, and gene flow are introduced by a perspective on the role of the fossil record in pollination biology. A speculative chapter on the constraints...

  12. Preliminary synthesis of pollination biology in the Cape flora

    CSIR Research Space (South Africa)

    Rebelo, AG

    1987-01-01

    Full Text Available biology are covered. Chapters reviewing plant breeding systems, insect, bird, mammal and wind pollination, and gene flow are introduced by a perspective on the role of the fossil record in pollination biology. A speculative chapter on the constraints...

  13. 76 FR 33121 - List of Approved Spent Fuel Storage Casks: HI-STORM Flood/Wind Addition

    Science.gov (United States)

    2011-06-08

    ... Storage Casks: HI-STORM Flood/Wind Addition AGENCY: Nuclear Regulatory Commission. ACTION: Direct final... regulations to add the Holtec HI-STORM Flood/Wind cask system to the ``List of Approved Spent Fuel Storage... Title 10 of the Code of Federal Regulations Section 72.214 to add the Holtec HI- STORM Flood/Wind cask...

  14. 76 FR 17019 - List of Approved Spent Fuel Storage Casks: HI-STORM Flood/Wind Addition

    Science.gov (United States)

    2011-03-28

    ... Storage Casks: HI-STORM Flood/Wind Addition AGENCY: Nuclear Regulatory Commission. ACTION: Direct final... regulations to add the HI-STORM Flood/Wind cask system to the ``List of Approved Spent Fuel Storage Casks... cask designs. Discussion This rule will add the Holtec HI-STORM Flood/Wind (FW) cask system to the list...

  15. Increased pollinator habitat enhances cacao fruit set and predator conservation.

    Science.gov (United States)

    Forbes, Samantha J; Northfield, Tobin D

    2017-04-01

    The unique benefits of wild pollinators to the productivity of agricultural crops have become increasingly recognized in recent decades. However, declines in populations of wild pollinator species, largely driven by the conversion of natural habitat to agricultural land and broad-spectrum pesticide use often lead reductions in the provision of pollination services and crop production. With growing evidence that targeted pollinator conservation improves crop yield and/or quality, particularly for pollination specialist crops, efforts are increasing to substitute agriculturally intensive practices with those that alleviate some of the negative impacts of agriculture on pollinators and the pollination services they provide, in part through the provision of suitable pollinator habitat. Further, similarities between the responses of some pollinators and predators to habitat management suggest that efforts to conserve pollinators may also encourage predator densities. We evaluated the effects of one habitat management practice, the addition of cacao fruit husks to a monoculture cacao farm, on the provision of pollination services and the densities of two groups of entomophagous predators. We also evaluated the impacts of cacao fruit husk addition on pollen limitation, by crossing this habitat manipulation with pollen supplementation treatments. The addition of cacao fruit husks increased the number of fruits per tree and along with hand pollination treatments, increased final yields indicating a promotion of the pollination ecosystem service provided by the specialist pollinators, midges. We also found that cacao fruit husk addition increased the densities of two predator groups, spiders and skinks. Further, the conservation of these predators did not inhibit pollination through pollinator capture or deterrence. The findings show that, with moderate habitat management, both pollinator and predator conservation can be compatible goals within a highly specialized plant-pollinator

  16. Plant-pollinator interactions in New Caledonia influenced by introduced honey bees.

    Science.gov (United States)

    Kato, Makoto; Kawakita, Atsushi

    2004-11-01

    The flora of New Caledonia is characterized by remarkably high species diversity, high endemicity, and an unusual abundance of archaic plant taxa. To investigate community-level pollination mutualism in this endemic ecosystem, we observed flower visitors on 99 plant species in 42 families of various types of vegetation. Among the 95 native plant species, the most dominant pollination system was melittophily (bee-pollinated, 46.3%), followed by phalaenophily (moth-pollinated, 20.0%), ornithophily (bird-pollinated, 11.6%), cantharophily (beetle-pollinated, 8.4%), myophily (fly-pollinated, 3.2%), chiropterophily (bat-pollinated, 3.2%), and anemophily (wind-pollinated, 3.2%). The prevalence of ornithophily by honeyeaters shows an ecological link to pollination mutualism in Australia. The relative dominance of phalaenophily is unique to New Caledonia, and is proposed to be related to the low diversity of the original bee fauna and the absence of long-tongued bees. Although some archaic plants maintain archaic plant-pollinator interactions, e.g., Zygogynum pollinated by micropterigid moths, or Hedycarya pollinated by thrips and staphylinid beetles, the most dominant organism observed on flowers was the introduced honey bee, Apis mellifera. The plant species now visited by honey bees are thought to have originally been pollinated by native solitary short-tongued bees. Our data suggest that the unique systems of pollination mutualism in New Caledonia are now endangered by the establishment of highly invasive honey bees.

  17. Pollination deficits in UK apple orchards

    Directory of Open Access Journals (Sweden)

    Simon Potts

    2013-10-01

    Full Text Available Apple production in the UK is worth over £100 million per annum and this production is heavily dependent on insect pollination. Despite its importance, it is not clear which insect pollinators carry out the majority of this pollination. Furthermore, it is unknown whether current UK apple production, in terms of both yield and quality, suffers pollination deficits and whether production value could be increased through effective management of pollination services. The present study set out to address some of these unknowns and showed that solitary bee activity is high in orchards and that they could be making a valuable contribution to pollination. Furthermore, fruit set and apple seed number were found to be suffering potential pollination deficits although these were not reflected in apple quality. Deficits could be addressed through orchard management practices to improve the abundance and diversity of wild pollinators. Such practices include provision of additional floral resources and nesting habitats as well as preservation of semi-natural areas. The cost effectiveness of such strategies would need to be understood taking into account the potential gains to the apple industry.

  18. Pollination deficits in UK apple orchards

    Directory of Open Access Journals (Sweden)

    Michael Paul Douglas Garratt

    2014-02-01

    Full Text Available Apple production in the UK is worth over £100 million per annum and this production is heavily dependent on insect pollination. Despite its importance, it is not clear which insect pollinators carry out the majority of this pollination. Furthermore, it is unknown whether current UK apple production, in terms of both yield and quality, suffers pollination deficits and whether production value could be increased through effective management of pollination services. The present study set out to address some of these unknowns and showed that solitary bee activity is high in orchards and that they could be making a valuable contribution to pollination. Furthermore, fruit set and apple seed number were found to be suffering potential pollination deficits although these were not reflected in apple quality. Deficits could be addressed through orchard management practices to improve the abundance and diversity of wild pollinators. Such practices include provision of additional floral resources and nesting habitats as well as preservation of semi-natural areas. The cost effectiveness of such strategies would need to be understood taking into account the potential gains to the apple industry.

  19. Additional acceleration of solar-wind particles in current sheets of the heliosphere

    Directory of Open Access Journals (Sweden)

    V. Zharkova

    2015-04-01

    Full Text Available Particles of fast solar wind in the vicinity of the heliospheric current sheet (HCS or in a front of interplanetary coronal mass ejections (ICMEs often reveal very peculiar energy or velocity profiles, density distributions with double or triple peaks, and well-defined streams of electrons occurring around or far away from these events. In order to interpret the parameters of energetic particles (both ions and electrons measured by the WIND spacecraft during the HCS crossings, a comparison of the data was carried out with 3-D particle-in-cell (PIC simulations for the relevant magnetic topology (Zharkova and Khabarova, 2012. The simulations showed that all the observed particle-energy distributions, densities, ion peak velocities, electron pitch angles and directivities can be fitted with the same model if the heliospheric current sheet is in a status of continuous magnetic reconnection. In this paper we present further observations of the solar-wind particles being accelerated to rather higher energies while passing through the HCS and the evidence that this acceleration happens well before the appearance of the corotating interacting region (CIR, which passes through the spacecraft position hours later. We show that the measured particle characteristics (ion velocity, electron pitch angles and the distance at which electrons are turned from the HCS are in agreement with the simulations of additional particle acceleration in a reconnecting HCS with a strong guiding field as measured by WIND. A few examples are also presented showing additional acceleration of solar-wind particles during their passage through current sheets formed in a front of ICMEs. This additional acceleration at the ICME current sheets can explain the anticorrelation of ion and electron fluxes frequently observed around the ICME's leading front. Furthermore, it may provide a plausible explanation of the appearance of bidirectional "strahls" (field-aligned most energetic

  20. Bee pollination improves crop quality, shelf life and commercial value.

    Science.gov (United States)

    Klatt, Björn K; Holzschuh, Andrea; Westphal, Catrin; Clough, Yann; Smit, Inga; Pawelzik, Elke; Tscharntke, Teja

    2014-01-22

    Pollination improves the yield of most crop species and contributes to one-third of global crop production, but comprehensive benefits including crop quality are still unknown. Hence, pollination is underestimated by international policies, which is particularly alarming in times of agricultural intensification and diminishing pollination services. In this study, exclusion experiments with strawberries showed bee pollination to improve fruit quality, quantity and market value compared with wind and self-pollination. Bee-pollinated fruits were heavier, had less malformations and reached higher commercial grades. They had increased redness and reduced sugar-acid-ratios and were firmer, thus improving the commercially important shelf life. Longer shelf life reduced fruit loss by at least 11%. This is accounting for 0.32 billion US$ of the 1.44 billion US$ provided by bee pollination to the total value of 2.90 billion US$ made with strawberry selling in the European Union 2009. The fruit quality and yield effects are driven by the pollination-mediated production of hormonal growth regulators, which occur in several pollination-dependent crops. Thus, our comprehensive findings should be transferable to a wide range of crops and demonstrate bee pollination to be a hitherto underestimated but vital and economically important determinant of fruit quality.

  1. Pollinator Foraging Adaptation and Coexistence of Competing Plants.

    Science.gov (United States)

    Revilla, Tomás A; Křivan, Vlastimil

    2016-01-01

    We use the optimal foraging theory to study coexistence between two plant species and a generalist pollinator. We compare conditions for plant coexistence for non-adaptive vs. adaptive pollinators that adjust their foraging strategy to maximize fitness. When pollinators have fixed preferences, we show that plant coexistence typically requires both weak competition between plants for resources (e.g., space or nutrients) and pollinator preferences that are not too biased in favour of either plant. We also show how plant coexistence is promoted by indirect facilitation via the pollinator. When pollinators are adaptive foragers, pollinator's diet maximizes pollinator's fitness measured as the per capita population growth rate. Simulations show that this has two conflicting consequences for plant coexistence. On the one hand, when competition between pollinators is weak, adaptation favours pollinator specialization on the more profitable plant which increases asymmetries in plant competition and makes their coexistence less likely. On the other hand, when competition between pollinators is strong, adaptation promotes generalism, which facilitates plant coexistence. In addition, adaptive foraging allows pollinators to survive sudden loss of the preferred plant host, thus preventing further collapse of the entire community.

  2. The Lubrication Ability of Ionic Liquids as Additives for Wind Turbine Gearboxes Oils

    Directory of Open Access Journals (Sweden)

    Miguel A. Gutierrez

    2016-05-01

    Full Text Available The amount of energy that can be gained from the wind is unlimited, unlike current energy sources such as fossil and coal. While there is an important push in the use of wind energy, gears and bearing components of the turbines often fail due to contact fatigue, causing costly repairs and downtime. The objective of this work is to investigate the potential tribological benefits of two phosphonium-based ionic liquids (ILs as additives to a synthetic lubricant without additives and to a fully formulated and commercially available wind turbine oil. In this work, AISI 52100 steel disks were tested in a ball-on-flat reciprocating tribometer against AISI 440C steel balls. Surface finish also affects the tribological properties of gear surfaces. In order to understand the combined effect of using the ILs with surface finish, two surface finishes were also used in this study. Adding ILs to the commercial available or synthetic lubricant reduced the wear scar diameter for both surface finishes. This decrease was particularly important for trihexyltetradecylphosphonium bis(trifluoromethylsulfonyl amide, where a wear reduction of the steel disk around 20% and 23% is reached when 5 wt % of this IL is added to the commercially available lubricant and to the synthetic lubricant without additives, respectively.

  3. Macroecology of pollination networks

    DEFF Research Database (Denmark)

    Nielsen, Kristian Trøjelsgaard; Olesen, Jens Mogens

    2013-01-01

    towards the tropics, and that network topology would be affected by current climate. Location Global. Methods Each network was organized as a presence/absence matrix, consisting of P plant species, A pollinator species and their links. From these matrices, network parameters were estimated. Additionally...... peaked at mid-latitude whereas modularity decreased linearly. Both patterns are suggestive of a more specialized interaction structure towards the tropics. In particular, mean annual precipitation appeared influential on network topology as both nestedness and modularity varied significantly. Importantly......Aim Interacting communities of species are organized into complex networks, and network analysis is reckoned to be a strong tool for describing their architecture. Many species assemblies show strong macroecological patterns, e.g. increasing species richness with decreasing latitude, but whether...

  4. Pollinator conservation — the difference between managing for pollination services and preserving pollinator diversity

    NARCIS (Netherlands)

    Senapathi, Deepa; Biesmeijer, J.C.; Breeze, T.; Kleijn, D.; Potts, S.G.; Carvalheiro, L.G.

    2015-01-01

    Our review looks at pollinator conservation and highlights the differences in approach between managing for pollination services and preserving pollinator diversity. We argue that ecosystem service management does not equal biodiversity conservation, and that maintaining species diversity is crucial

  5. Pyrodiversity begets plant-pollinator community diversity.

    Science.gov (United States)

    Ponisio, Lauren C; Wilkin, Kate; M'Gonigle, Leithen K; Kulhanek, Kelly; Cook, Lindsay; Thorp, Robbin; Griswold, Terry; Kremen, Claire

    2016-05-01

    Fire has a major impact on the structure and function of many ecosystems globally. Pyrodiversity, the diversity of fires within a region (where diversity is based on fire characteristics such as extent, severity, and frequency), has been hypothesized to promote biodiversity, but changing climate and land management practices have eroded pyrodiversity. To assess whether changes in pyrodiversity will have impacts on ecological communities, we must first understand the mechanisms that might enable pyrodiversity to sustain biodiversity, and how such changes might interact with other disturbances such as drought. Focusing on plant-pollinator communities in mixed-conifer forest with frequent fire in Yosemite National Park, California, we examine how pyrodiversity, combined with drought intensity, influences those communities. We find that pyrodiversity is positively related to the richness of the pollinators, flowering plants, and plant-pollinator interactions. On average, a 5% increase in pyrodiversity led to the gain of approximately one pollinator and one flowering plant species and nearly two interactions. We also find that a diversity of fire characteristics contributes to the spatial heterogeneity (β-diversity) of plant and pollinator communities. Lastly, we find evidence that fire diversity buffers pollinator communities against the effects of drought-induced floral resource scarcity. Fire diversity is thus important for the maintenance of flowering plant and pollinator diversity and predicted shifts in fire regimes to include less pyrodiversity compounded with increasing drought occurrence will negatively influence the richness of these communities in this and other forested ecosystems. In addition, lower heterogeneity of fire severity may act to reduce spatial turnover of plant-pollinator communities. The heterogeneity of community composition is a primary determinant of the total species diversity present in a landscape, and thus, lower pyrodiversity may

  6. Rain pollination provides reproductive assurance in a deceptive orchid

    Science.gov (United States)

    Fan, Xu-Li; Barrett, Spencer C. H.; Lin, Hua; Chen, Ling-Ling; Zhou, Xiang; Gao, Jiang-Yun

    2012-01-01

    Background and Aims Abiotic pollination by wind or water is well established in flowering plants. In some species pollination by rain splashes, a condition known as ombrophily, has been proposed as a floral strategy. However, evidence for this type of abiotic pollination has remained controversial and many reported cases have subsequently been shown to be false. This study investigates ombrophily in the deceptive orchid Acampe rigida to determine the mechanism by which this species is able to maintain high fecundity, despite flowering during the rainy season in south-west China when pollinators are scarce. Methods The floral mechanisms promoting rain pollination in A. rigida were observed and described in detail. Controlled pollination experiments and observations of floral visitors were conducted. A field experiment using rain shelters at 14 sites in Guangxi, south-west China, evaluated the contribution of rain pollination to fruit-set. Key Results During rainfall, raindrops physically flicked away the anther cap exposing the pollinarium. Raindrops then caused pollinia to be ejected upwards with the strap-like stipe pulling them back and causing them to fall into the stigmatic cavity, resulting in self-pollination. Neither flower nor pollen function were damaged by water. Although A. rigida is self-compatible, it is incapable of autonomous self-pollination without the assistance of rain splashes. The results of the rain-sheltering experiment indicated that rain pollination contributed substantially to increasing fruit-set, although there was variation among sites in the intensity of this effect. Conclusions A. rigida flowers during the rainy season, when pollinators are scarce, and ombrophily functions to provide reproductive assurance without compromising opportunities for outcrossing. PMID:22851311

  7. Large-scale pollination experiment demonstrates the importance of insect pollination in winter oilseed rape.

    Science.gov (United States)

    Lindström, Sandra A M; Herbertsson, Lina; Rundlöf, Maj; Smith, Henrik G; Bommarco, Riccardo

    2016-03-01

    Insect pollination, despite its potential to contribute substantially to crop production, is not an integrated part of agronomic planning. A major reason for this are knowledge gaps in the contribution of pollinators to yield, which partly result from difficulties in determining area-based estimates of yield effects from insect pollination under field conditions. We have experimentally manipulated honey bee Apis mellifera densities at 43 oilseed rape Brassica napus fields over 2 years in Scandinavia. Honey bee hives were placed in 22 fields; an additional 21 fields without large apiaries in the surrounding landscape were selected as controls. Depending on the pollination system in the parental generation, the B. napus cultivars in the crop fields are classified as either open-pollinated or first-generation hybrids, with both types being open-pollinated in the generation of plants cultivated in the fields. Three cultivars of each type were grown. We measured the activity of flower-visiting insects during flowering and estimated yields by harvesting with small combine harvesters. The addition of honey bee hives to the fields dramatically increased abundance of flower-visiting honey bees in those fields. Honey bees affected yield, but the effect depended on cultivar type (p = 0.04). Post-hoc analysis revealed that open-pollinated cultivars, but not hybrid cultivars, had 11% higher yields in fields with added honey bees than those grown in the control fields (p = 0.07). To our knowledge, this is the first whole-field study in replicated landscapes to assess the benefit of insect pollination in oilseed rape. Our results demonstrate that honey bees have the potential to increase oilseed rape yields, thereby emphasizing the importance of pollinator management for optimal cultivation of oilseed rape.

  8. Pollinator Protection Strategic Plan

    Science.gov (United States)

    Developed by EPA, this ensures that pesticide risk assessments and risk management decisions use best available information and scientific methods, and full evaluation of pollinator protection when making registration decisions.

  9. Hedgerows Have a Barrier Effect and Channel Pollinator Movement in the Agricultural Landscape

    Directory of Open Access Journals (Sweden)

    Klaus Felix

    2015-01-01

    Full Text Available Agricultural intensification and the subsequent fragmentation of semi-natural habitats severely restrict pollinator and pollen movement threatening both pollinator and plant species. Linear landscape elements such as hedgerows are planted for agricultural and conservation purposes to increase the resource availability and habitat connectivity supporting populations of beneficial organisms such as pollinators. However, hedgerows may have unexpected effects on plant and pollinator persistence by not just channeling pollinators and pollen along, but also restricting movement across the strip of habitat. Here, we tested how hedgerows influence pollinator movement and pollen flow. We used fluorescent dye particles as pollen analogues to track pollinator movement between potted cornflowers Centaurea cyanus along and across a hedgerow separating two meadows. The deposition of fluorescent dye was significantly higher along the hedgerow than across the hedgerow and into the meadow, despite comparable pollinator abundances. The differences in pollen transfer suggest that hedgerows can affect pollinator and pollen dispersal by channeling their movement and acting as a permeable barrier. We conclude that hedgerows in agricultural landscapes can increase the connectivity between otherwise isolated plant and pollinator populations (corridor function, but can have additional, and so far unknown barrier effects on pollination services. Functioning as a barrier, linear landscape elements can impede pollinator movement and dispersal, even for highly mobile species such as bees. These results should be considered in future management plans aiming to enhance the persistence of threatened pollinator and plant populations by restoring functional connectivity and to ensure sufficient crop pollination in the agricultural landscape.

  10. Pollination services enhanced with urbanization despite increasing pollinator parasitism.

    Science.gov (United States)

    Theodorou, Panagiotis; Radzevičiūtė, Rita; Settele, Josef; Schweiger, Oliver; Murray, Tomás E; Paxton, Robert J

    2016-06-29

    Animal-mediated pollination is required for the reproduction of the majority of angiosperms, and pollinators are therefore essential for ecosystem functioning and the economy. Two major threats to insect pollinators are anthropogenic land-use change and the spread of pathogens, whose effects may interact to impact pollination. Here, we investigated the relative effects on the ecosystem service of pollination of (i) land-use change brought on by agriculture and urbanization as well as (ii) the prevalence of pollinator parasites, using experimental insect pollinator-dependent plant species in natural pollinator communities. We found that pollinator habitat (i.e. availability of nesting resources for ground-nesting bees and local flower richness) was strongly related to flower visitation rates at the local scale and indirectly influenced plant pollination success. At the landscape scale, pollination was positively related to urbanization, both directly and indirectly via elevated visitation rates. Bumblebees were the most abundant pollinator group visiting experimental flowers. Prevalence of trypanosomatids, such as the common bumblebee parasite Crithidia bombi, was higher in urban compared with agricultural areas, a relationship which was mediated through higher Bombus abundance. Yet, we did not find any top-down, negative effects of bumblebee parasitism on pollination. We conclude that urban areas can be places of high transmission of both pollen and pathogens. © 2016 The Author(s).

  11. Pollination services enhanced with urbanization despite increasing pollinator parasitism

    Science.gov (United States)

    Radzevičiūtė, Rita; Murray, Tomás E.

    2016-01-01

    Animal-mediated pollination is required for the reproduction of the majority of angiosperms, and pollinators are therefore essential for ecosystem functioning and the economy. Two major threats to insect pollinators are anthropogenic land-use change and the spread of pathogens, whose effects may interact to impact pollination. Here, we investigated the relative effects on the ecosystem service of pollination of (i) land-use change brought on by agriculture and urbanization as well as (ii) the prevalence of pollinator parasites, using experimental insect pollinator-dependent plant species in natural pollinator communities. We found that pollinator habitat (i.e. availability of nesting resources for ground-nesting bees and local flower richness) was strongly related to flower visitation rates at the local scale and indirectly influenced plant pollination success. At the landscape scale, pollination was positively related to urbanization, both directly and indirectly via elevated visitation rates. Bumblebees were the most abundant pollinator group visiting experimental flowers. Prevalence of trypanosomatids, such as the common bumblebee parasite Crithidia bombi, was higher in urban compared with agricultural areas, a relationship which was mediated through higher Bombus abundance. Yet, we did not find any top-down, negative effects of bumblebee parasitism on pollination. We conclude that urban areas can be places of high transmission of both pollen and pathogens. PMID:27335419

  12. Western honey bee management for crop pollination | Toni | African ...

    African Journals Online (AJOL)

    Apis mellifera is widely used for pollination purposes for several reasons, including its polylectic nature, its wide distribution, its relatively ease and low cost management, and hive products from which the beekeeper get additional incomes. The Western honey bee is used to pollinate 66 commodities on all continents, except ...

  13. Pollination syndromes in a specialised plant-pollinator interaction: does floral morphology predict pollinators in Calceolaria?

    Science.gov (United States)

    Murúa, M; Espíndola, A

    2015-03-01

    Pollination syndromes are defined as suites of floral traits evolved in response to selection imposed by a particular group of pollinators (e.g., butterflies, hummingbirds, bats). Although numerous studies demonstrated their occurrence in plants pollinated by radically different pollinators, it is less known whether it is possible to identify them within species pollinated by one functional pollinator group. In such a framework, we expect floral traits to evolve also in response to pollinator subgroups (e.g., species, genera) within that unique functional group. On this, specialised pollination systems represent appropriate case studies to test such expectations. Calceolaria is a highly diversified plant genus pollinated by oil-collecting bees in genera Centris and Chalepogenus. Variation in floral traits in Calceolaria has recently been suggested to reflect adaptations to pollinator types. However, to date no study has explicitly tested that observation. In this paper, we quantitatively test that hypothesis by evaluating the presence of pollination syndromes within the specialised pollination system formed by several Calceolaria and their insect pollinators. To do so, we use multivariate approaches and explore the structural matching between the morphology of 10 Calceolaria taxa and that of their principal pollinators. Our results identify morphological matching between floral traits related to access to the reward and insect traits involved in oil collection, confirming the presence of pollinator syndromes in Calceolaria. From a general perspective, our findings indicate that the pollination syndrome concept can be also extended to the intra-pollinator group level. © 2014 German Botanical Society and The Royal Botanical Society of the Netherlands.

  14. How specialised is bird pollination in the Cactaceae?

    Science.gov (United States)

    Gorostiague, P; Ortega-Baes, P

    2016-01-01

    Many cactus species produce 'bird' flowers; however, the reproductive biology of the majority of these species has not been studied. Here, we report on a study of the pollination of two species from the Cleistocactus genus, cited as an ornithophilous genus, in the context of the different ways in which they are specialised to bird pollination. In addition, we re-evaluate the level of specialisation of previous studies of cacti with bird pollination and evaluate how common phenotypic specialisation to birds is in this family. Both Cleistocactus species exhibited ornithophilous floral traits. Cleistocactus baumannii was pollinated by hummingbirds, whereas Cleistocactus smaragdiflorus was pollinated by hummingbirds and bees. Pollination by birds has been recorded in 27 cactus species, many of which exhibit ornithophilous traits; however, they show generalised pollination systems with bees, bats or moths in addition to birds being their floral visitors. Of all cactus species, 27% have reddish flowers. This trait is associated with diurnal anthesis and a tubular shape. Phenotypic specialisation to bird pollination is recognised in many cactus species; however, it is not predictive of functional and ecological specialisation in this family. © 2014 German Botanical Society and The Royal Botanical Society of the Netherlands.

  15. The Effect of Additional Mooring Chains on the Motion Performance of a Floating Wind Turbine with a Tension Leg Platform

    Directory of Open Access Journals (Sweden)

    Jinping Ou

    2012-04-01

    Full Text Available In this study, two types of floating offshore wind turbine (FOWT systems were proposed: a traditional tension leg platform (TLP type and a new TLP type with additional mooring chains. They were both based on the National Renewable Energy Laboratory 5 MW offshore wind turbine model. Taking the coupled effect of dynamic response of the top wind turbine, tower support structure and lower mooring system into consideration, not only were the 1/60 scale model tests for the two floating wind turbine systems done in HIT’s wind-wave tunnel according to the typical design conditions in IEC61400-3 code, but also the numerical simulations corresponding to the scaled model tests were performed by advanced numerical tools. As a result, the numerical results displayed good agreement with the test data. Moreover, the additional mooring chains could play an active role in reducing the surge displacement, surge acceleration and typical tension leg force responses of the FOWT system, which is very beneficial for ensuring the good operational performance and the safety of the FOWT system.

  16. 76 FR 17037 - List of Approved Spent Fuel Storage Casks: HI-STORM Flood/Wind Addition

    Science.gov (United States)

    2011-03-28

    ...-0007] RIN 3150-AI90 List of Approved Spent Fuel Storage Casks: HI-STORM Flood/Wind Addition AGENCY... or the Commission) is proposing to amend its spent fuel storage cask regulations to add the HI-STORM...: June 13, 2011. SAR Submitted by: Holtec International, Inc. SAR Title: Safety Analysis Report on the HI...

  17. Development of procedures for the acquisition of metal Additive Manufacturing (AM) parts for use in the CSIR's wind tunnel models

    CSIR Research Space (South Africa)

    Johnston, C

    2015-11-04

    Full Text Available The first Additive Manufacturing (AM) non-load-bearing, client furnished part was used in the CSIR’s wind tunnels in 2007. The advent of metal-grown materials, and the acquisition of machines to grow them in South Africa, has made it feasible...

  18. Interaction of additive noise and nonlinear dynamics in the double-gyre wind-driven ocean circulation

    NARCIS (Netherlands)

    Sapsis, T.; Dijkstra, H.A.

    2013-01-01

    In this paper the authors study the interactions of additive noise and nonlinear dynamics in a quasi-geostrophicmodel of the double-gyre wind-driven ocean circulation. The recently developed framework of dynamically orthogonal field theory is used to determine the statistics of the flows that arise

  19. Ants and ant scent reduce bumblebee pollination of artificial flowers.

    Science.gov (United States)

    Cembrowski, Adam R; Tan, Marcus G; Thomson, James D; Frederickson, Megan E

    2014-01-01

    Ants on flowers can disrupt pollination by consuming rewards or harassing pollinators, but it is difficult to disentangle the effects of these exploitative and interference forms of competition on pollinator behavior. Using highly rewarding and quickly replenishing artificial flowers that simulate male or female function, we allowed bumblebees (Bombus impatiens) to forage (1) on flowers with or without ants (Myrmica rubra) and (2) on flowers with or without ant scent cues. Bumblebees transferred significantly more pollen analogue both to and from ant-free flowers, demonstrating that interference competition with ants is sufficient to modify pollinator foraging behavior. Bees also removed significantly less pollen analogue from ant-scented flowers than from controls, making this the first study to show that bees can use ant scent to avoid harassment at flowers. Ant effects on pollinator behavior, possibly in addition to their effects on pollen viability, may contribute to the evolution of floral traits minimizing ant visitation.

  20. Pollinator Research at EPA

    Science.gov (United States)

    Of great concern, honey bee populations have experienced dramatic declines in the US and in many other countries. In response to this issue, the White House instructed the EPA and USDA to lead a Federal Task Force to develop a National Strategy on Pollinator Health which called f...

  1. Indirect interactions between invasive and native plants via pollinators

    Science.gov (United States)

    Kaiser-Bunbury, Christopher N.; Müller, Christine B.

    2009-03-01

    In generalised pollination systems, the presence of alien plant species may change the foraging behaviour of pollinators on native plant species, which could result in reduced reproductive success of native plant species. We tested this idea of indirect interactions on a small spatial and temporal scale in a field study in Mauritius, where the invasive strawberry guava, Psidium cattleianum, provides additional floral resources for insect pollinators. We predicted that the presence of flowering guava would indirectly and negatively affect the reproductive success of the endemic plant Bertiera zaluzania, which has similar flowers, by diverting shared pollinators. We removed P. cattleianum flowers within a 5-m radius from around half the B. zaluzania target plants (treatment) and left P. cattleianum flowers intact around the other half (control). By far, the most abundant and shared pollinator was the introduced honey bee, Apis mellifera, but its visitation rates to treatment and control plants were similar. Likewise, fruit and seed set and fruit size and weight of B. zaluzania were not influenced by the presence of P. cattleianum flowers. Although other studies have shown small-scale effects of alien plant species on neighbouring natives, we found no evidence for such negative indirect interactions in our system. The dominance of introduced, established A. mellifera indicates their replacement of native insect flower visitors and their function as pollinators of native plant species. However, the pollination effectiveness of A. mellifera in comparison to native pollinators is unknown.

  2. Change of floral orientation within an inflorescence affects pollinator behavior and pollination efficiency in a bee-pollinated plant, Corydalis sheareri.

    Directory of Open Access Journals (Sweden)

    Hui Wang

    Full Text Available Vertical raceme or spike inflorescences that are bee-pollinated tend to present their flowers horizontally. Horizontal presentation of flowers is hypothesized to enhance pollinator recognition and pollination precision, and it may also ensure greater consistency of pollinator movement on inflorescences. We tested the hypotheses using bee-pollinated Corydalis sheareri which has erect inflorescences consisting of flowers with horizontal orientation. We altered the orientation of individual flowers and prepared three types of inflorescences: (i unmanipulated inflorescences with horizontal-facing flowers, (ii inflorescences with flowers turned upward, and (iii inflorescences with flowers turned downward. We compared number of inflorescences approached and visited, number of successive probes within an inflorescence, the direction percentage of vertical movement on inflorescences, efficiency of pollen removal and seed production per inflorescence. Deviation from horizontal orientation decreased both approaches and visits by leafcutter bees and bumble bees to inflorescences. Changes in floral orientation increased the proportion of downward movements by leafcutter bees and decreased the consistency of pollinator movement on inflorescences. In addition, pollen removal per visit and seed production per inflorescence also declined with changes of floral orientation. In conclusion, floral orientation seems more or less optimal as regards bee behavior and pollen transfer for Corydalis sheareri. A horizontal orientation may be under selection of pollinators and co-adapt with other aspects of the inflorescence and floral traits.

  3. Occurrence of internally ovipositing non-agaonid wasps and pollination mode of the associated agaonid wasps

    Directory of Open Access Journals (Sweden)

    Xinmin Zhang

    2017-06-01

    In addition to the agaonids, figs support many species of ‘non-pollinating fig wasps’ (NPFW that are typically ovule gallers or parasitoids. These mainly oviposit from outside the figs but there are a few species of NPFW that are like agaonids and enter the figs to oviposit. Two of the eight Eupristina pollinated fig trees support host specific internally-ovipositing fig wasps belonging to the chalcidoid genera Diaziella (Sycoecinae and Lipothymus (Otitesellinae. Reflecting the trees' pollination modes, these fig wasps act as supplementary pollinators of F. curtipes, but not of Ficus glaberrima, where agaonid pollination is active.

  4. Hotspots of human nutrition: Micronutrient supply, demand, and pollinator dependence

    Science.gov (United States)

    Dombeck, E.; Chaplin-Kramer, R.; Mueller, M.; Mueller, N. D.; Foley, J. A.

    2012-12-01

    While our caloric needs can mostly be met by wind-pollinated crops such as cereals, a recent analysis of USDA data shows that animal-pollinated crops contain the vast majority of many essential nutrients, including vitamins A and C, calcium, fluoride, and folic acid. In this work we combined global crop yield data with data on nutritional content in each crop to map nutrient production around the world, and to illustrate the value of pollination services to human nutrition. Spatially explicit crop yields (at 5 min resolution) were multiplied by crop nutrient content and by crop dependence on pollination to map where reductions in total nutrient production would occur if pollination services were removed. Nutrient demand maps (human nutrient requirements multiplied by population density) were generated to identify regions where local reduction in pollination services could threaten nutritional security. Nutrient deficiency maps (nutrient supply minus nutrient demand) were also created to identify hotspots where local crop production is not adequate to meet local nutritional needs.

  5. Cycads: their evolution, toxins, herbivores and insect pollinators

    Science.gov (United States)

    Schneider, Dietrich; Wink, Michael; Sporer, Frank; Lounibos, Philip

    2002-06-01

    Palaeobiological evidence indicates that gymnosperms were wind-pollinated and that insect pollination began in angiosperms in the Lower Cretaceous (ca. 135 mya) leading to close associations between higher plants and their pollinators. Cycads, which were widespread and pervasive throughout the Mesozoic (250-65 mya) are among the most primitive living seed-plants found today. Because pollination by beetles and by thrips has now been detected in several modern cycads, it is attractive to speculate that some insects and cycads had already developed similar mutualistic interactions in the Triassic (250-205 mya), long before the advent of angiosperms. We also draw attention to another key factor in this insect-plant relationship, namely secondary, defensive plant substances which must always have controlled interspecific interactions. Cycads mainly produce toxic azoglucosides and neurotoxic non-protein amino acids (e.g. BMAA), which apparently are crucial elements in the development and maintenance of mutualism (pollination) and parasitism (herbivory) by cycad-linked herbivores. We now add new results on the uptake and storage of the main toxin, cycasin, of the Mexican cycad Zamia furfuracea by its pollinator, the weevil Rhopalotria mollis, and by a specialist herbivore of Zamia integrifolia, the aposematic Atala butterfly Eumaeus atala.

  6. High species richness of native pollinators in Brazilian tomato crops

    Directory of Open Access Journals (Sweden)

    C. M. Silva-Neto

    Full Text Available Abstract Pollinators provide an essential service to natural ecosystems and agriculture. In tomatoes flowers, anthers are poricidal, pollen may drop from their pore when flowers are shaken by the wind. However, bees that vibrate these anthers increase pollen load on the stigma and in fruit production. The present study aimed to identify the pollinator richness of tomato flowers and investigate their morphological and functional traits related to the plant-pollinator interaction in plantations of Central Brazil. The time of anthesis, flower duration, and the number and viability of pollen grains and ovules were recorded. Floral visitors were observed and collected. Flower buds opened around 6h30 and closed around 18h00. They reopened on the following day at the same time in the morning, lasting on average 48 hours. The highest pollen availability occurred during the first hours of anthesis. Afterwards, the number of pollen grains declined, especially between 10h00 to 12h00, which is consistent with the pollinator visitation pattern. Forty bee species were found in the tomato fields, 30 of which were considered pollinators. We found that during the flowering period, plants offered an enormous amount of pollen to their visitors. These may explain the high richness and amount of bees that visit the tomato flowers in the study areas. The period of pollen availability and depletion throughout the day overlapped with the bees foraging period, suggesting that bees are highly effective in removing pollen grains from anthers. Many of these grains probably land on the stigma of the same flower, leading to self-pollination and subsequent fruit development. Native bees (Exomalopsis spp. are effective pollinators of tomato flowers and are likely to contribute to increasing crop productivity. On the other hand, here tomato flowers offer large amounts of pollen resource to a high richness and amount of bees, showing a strong plant-pollinator interaction in the

  7. Pollination syndromes ignored

    DEFF Research Database (Denmark)

    Maruyama, P. K.; Oliveira, G. M.; Ferreira, Célia Maria Dias

    2013-01-01

    Generalization prevails in flower-animal interactions, and although animal visitors are not equally effective pollinators, most interactions likely represent an important energy intake for the animal visitor. Hummingbirds are nectar-feeding specialists, and many tropical plants are specialized...... toward hummingbird-pollination. In spite of this, especially in dry and seasonal tropical habitats, hummingbirds may often rely on non-ornithophilous plants to meet their energy requirements. However, quantitative studies evaluating the relative importance of ornithophilous vs. non-ornithophilous plants...... for hummingbirds in these areas are scarce. We here studied the availability and use of floral resources by hummingbirds in two different areas of the Cerrado, the seasonal savannas in Central Brazil. Roughly half the hummingbird visited plant species were non-ornithophilous, and these contributed greatly...

  8. Materials and Additive Manufacturing for Energy Efficiency in Wind Turbine and Aircraft Industries

    Energy Technology Data Exchange (ETDEWEB)

    Datskos, Panos G [ORNL; Polyzos, Georgios [ORNL; Clemons, Art [ORNL; Bolton, Paul [Piedmont Propulsion Systems, LLC; Hollander, Aaron [First Aviation Services Inc., Westport, CT

    2016-05-04

    The purpose of this project was to develop surface treatments which will inhibit the formation of ice on turbine blades and propellers. ORNL worked with Piedmont Propulsion Systems, LLC and First Aviation Services Inc. to demonstrate a new surface treatment for two primary markets, aviation and wind turbines, as well as secondary markets such as power lines, bridges, boats, roofs and antennas among others. Exploring alternative surface treatments for wind turbines will provide anti-icing properties and erosion/abrasion prevention properties similar to those for aviation applications. A series of superhydrophobic coating materials was synthesized and successfully applied on anti-ice tape materials that could be used in a wide range of wind turbine and aviation applications to prevent ice accumulation. The coatings developed in this project were based on superhydrophobic particles of different geometries and sizes that were homogeneously dispersed in polymeric binders. The superhydrophobic features of the coatings are volumetric and their abrasion resistance was evaluated. Future research will involve the demonstration of anti-icing properties of the surface treatment developed in this project.

  9. Pollination syndromes in African Marantaceae.

    Science.gov (United States)

    Ley, Alexandra C; Classen-Bockhoff, Regine

    2009-07-01

    The Marantaceae (550 spp.) is the most derived family in the order Zingiberales and exhibits a complex explosive pollination mechanism. To understand the evolutionary significance of this unique process of pollen transfer, comparative morphological and ecological studies were conducted in Gabon. During a total stay of 11 months, 31 species of Marantaceae were investigated at different sites in Gabon. The study included analyses of floral diversity, observations on the pollinator spectrum as well as ecological measurements (e.g. nectar sugar concentration and volume). Analyses reveal five flower types based on flower size and pigmentation, spatial arrangement of the floral tube and presence/absence of nectar guides and conspicuous outer staminodes. Each type is associated with a specific functional pollinator group leading to the description of distinct pollination syndromes. The 'small (horizontal)' flowers are predominantly pollinated by small bees (Thrinchostoma spp., Allodapula ornaticeps), the 'large (horizontal)' and 'medium-sized (horizontal)' flowers by medium-sized bees (Amegilla vivida, Thrinchostoma bicometes), the 'locked (horizontal)' flowers by large bees (Xylocopa nigrita, X. varipes) and the '(large) vertical' flowers by sunbirds. The longevity of Marantaceae individuals and the omnipresence of their pollinators allowed the specialization to a given functional pollinator group. Intermediate ecological values, however, make occasional pollinator overlaps possible, indicating potential pathways of pollinator shifts. Similar radiation tendencies observed on other continents hint at similar selective pressures and evolutionary constraints.

  10. Pollinators: Downward Trends and Lofty Goals

    Science.gov (United States)

    Pollinators are essential to natural and managed landscapes. By providing critical pollination services, bees, birds, beetles, butterflies, bats and other animals enhance biodiversity and contribute to production of many nutritious foods. Honey bees alone pollinate 90 commercia...

  11. Synergistic effects of non-Apis bees and honey bees for pollination services

    Science.gov (United States)

    Brittain, Claire; Williams, Neal; Kremen, Claire; Klein, Alexandra-Maria

    2013-01-01

    In diverse pollinator communities, interspecific interactions may modify the behaviour and increase the pollination effectiveness of individual species. Because agricultural production reliant on pollination is growing, improving pollination effectiveness could increase crop yield without any increase in agricultural intensity or area. In California almond, a crop highly dependent on honey bee pollination, we explored the foraging behaviour and pollination effectiveness of honey bees in orchards with simple (honey bee only) and diverse (non-Apis bees present) bee communities. In orchards with non-Apis bees, the foraging behaviour of honey bees changed and the pollination effectiveness of a single honey bee visit was greater than in orchards where non-Apis bees were absent. This change translated to a greater proportion of fruit set in these orchards. Our field experiments show that increased pollinator diversity can synergistically increase pollination service, through species interactions that alter the behaviour and resulting functional quality of a dominant pollinator species. These results of functional synergy between species were supported by an additional controlled cage experiment with Osmia lignaria and Apis mellifera. Our findings highlight a largely unexplored facilitative component of the benefit of biodiversity to ecosystem services, and represent a way to improve pollinator-dependent crop yields in a sustainable manner. PMID:23303545

  12. Synergistic effects of non-Apis bees and honey bees for pollination services.

    Science.gov (United States)

    Brittain, Claire; Williams, Neal; Kremen, Claire; Klein, Alexandra-Maria

    2013-03-07

    In diverse pollinator communities, interspecific interactions may modify the behaviour and increase the pollination effectiveness of individual species. Because agricultural production reliant on pollination is growing, improving pollination effectiveness could increase crop yield without any increase in agricultural intensity or area. In California almond, a crop highly dependent on honey bee pollination, we explored the foraging behaviour and pollination effectiveness of honey bees in orchards with simple (honey bee only) and diverse (non-Apis bees present) bee communities. In orchards with non-Apis bees, the foraging behaviour of honey bees changed and the pollination effectiveness of a single honey bee visit was greater than in orchards where non-Apis bees were absent. This change translated to a greater proportion of fruit set in these orchards. Our field experiments show that increased pollinator diversity can synergistically increase pollination service, through species interactions that alter the behaviour and resulting functional quality of a dominant pollinator species. These results of functional synergy between species were supported by an additional controlled cage experiment with Osmia lignaria and Apis mellifera. Our findings highlight a largely unexplored facilitative component of the benefit of biodiversity to ecosystem services, and represent a way to improve pollinator-dependent crop yields in a sustainable manner.

  13. Pollination systems and floral traits in cerrado woody species of the Upper Taquari region (central Brazil

    Directory of Open Access Journals (Sweden)

    F. Q. Martins

    Full Text Available Plant species present flowers with varied morphological and functional features, which may be associated to pollination systems, including species pollinated by wind, beetles, moths, bees, small insects, birds, or bats. We calculated the frequencies of the pollination systems among woody species in five cerrado fragments in central-western Brazil and tested whether the pollination systems were indeed related to floral traits. We sampled 2,280 individuals, belonging to 121 species, ninety-nine of which were described in relation to all floral traits. Most species had diurnal anthesis, pale colors, and open flowers. The most frequent groups were those composed by the species pollinated by bees, small insects, and moths. A Principal Component Analysis of the species and floral traits showed that there was a grouping among species with some pollination systems, such as those pollinated mainly by beetles, moths, birds, and bats, for which inferences based on the floral traits are recommended in cerrado sites. For the species pollinated mainly by bees or small insects, inferences based on the floral traits are not recommended, due to the large dispersion of the species scores and overlapping between these two groups, which probably occurred due to the specificity absence in plant-pollinator relationships.

  14. Patch Size, Pollinator Behavior, and Pollinator Limitation in Catnip.

    Science.gov (United States)

    Sih, Andrew; Baltus, Marie-Sylvie

    1987-12-01

    We examined the effects of the patch size of catnip, Nepeta cataria, on pollinator visitation rates and pollinator limitation. The most important floral visitors were honey bees (Apis mellifera), solitary bees (Halictidae), and bumble bees (Bombus spp.). Our first goal was to see how spatial variation in patch size affected the rate at which individual flowers received pollinator visits (visitation rate). Visitation rate was higher in larger patches for honey bees and bumble bees, but lower for solitary bees. Patch size explained 74-83% of the variation in visitation rate. Intraspecific isolation also had an effect: isolated patches received relatively few visits. Visitation rate depended both on visitor abundance and on the proportion of flowers entered during one visit. All three visitor types wee more abundant in larger patches, i.e., flowers showed mutual attraction of pollinators. Relative to a visit to a small patch, during a visit to a large patch, honey bees visited more flowers but a lower proportion of flowers; solitary bees visited fewer flowers and thus a lower proportion of flowers; and bumble bees visited not only more flowers but a higher proportion of flowers as well. Thus within patches, flowers competed for visits from honey bees and solitary bees but showed facilitation regarding bumble bee visits. Our second goal was to relate patch size and visitation rates to immediate pollinator limitation. Comparisons of the percent of capsules setting seed (fruit set) of open-pollinated, hand-pollinated, and bagged flowers were used to evaluate pollinator limitation. The ranking of fruit set was: hand-pollinated > open-pollinated > bagged. Patch size did not affect fruit set in hand-pollinated or bagged flowers; however, for open-pollinated flowers, fruit set was lower in smaller patches. patch size explained 63% of the variation in pollinator limitation. The effect of patch size comes through its effects on visitation rates. A multiple regression model

  15. Does intraspecific behavioural variation of pollinator species influence pollination? A quantitative study with hummingbirds and a Neotropical shrub.

    Science.gov (United States)

    Maruyama, P K; Justino, D G; Oliveira, P E

    2016-11-01

    Floral visitors differ in their efficacy as pollinators, and the impact of different pollinator species on pollen flow and plant reproduction has been frequently evaluated. In contrast, the impact of intraspecific behavioural changes on their efficacy as pollinators has seldom been quantified. We studied a self-incompatible shrub Palicourea rigida (Rubiaceae) and its hummingbird pollinators, which adjust their behaviour according to floral resource availability. Fluorescence microscopy was used to access pollen tube growth and incompatibility reaction in pistils after a single visit of territorial or intruder hummingbirds in two populations. To characterise the plant populations and possible differences in resource availability between areas we used a three-term quadrat variance method to detect clusters of floral resources. Within-species variation in foraging behaviour, but not species identity, affected pollinator efficacy. Effectively, hummingbirds intruding into territories deposited more compatible pollen grains on P. rigida stigmas than territory holders in both study areas. Additionally, territory holders deposited more incompatible than compatible pollen grains. Our results imply that intraspecific foraging behaviour variation has consequences for pollination success. Quantifying such variation and addressing the implications of intraspecific variability contribute to a better understanding of the dynamics and consequences of plant-pollinator interactions. © 2016 German Botanical Society and The Royal Botanical Society of the Netherlands.

  16. EG ANDROMEDAE: A NEW ORBIT AND ADDITIONAL EVIDENCE FOR A PHOTOIONIZED WIND

    Energy Technology Data Exchange (ETDEWEB)

    Kenyon, Scott J. [Smithsonian Astrophysical Observatory, 60 Garden Street, Cambridge, MA 02138 (United States); Garcia, Michael R., E-mail: skenyon@cfa.harvard.edu, E-mail: michael.r.garcia@nasa.gov [NASA Headquarters, Mail Suite 3Y28, 300 E Street SW, Washington, DC 20546-0001 (United States)

    2016-07-01

    We analyze a roughly 20 yr set of spectroscopic observations for the symbiotic binary EG And. Radial velocities derived from echelle spectra are best fit with a circular orbit having an orbital period of P = 483.3 ± 1.6 days and semi-amplitude K = 7.34 ± 0.07 km s{sup −1}. Combined with previous data, these observations rule out an elliptical orbit at the 10 σ level. Equivalent widths of H i Balmer emission lines and various absorption features vary in phase with the orbital period. Relative to the radius of the red giant primary, the apparent size of the H ii region is consistent with a model where a hot secondary star with effective temperature T{sub h} ≈ 75,000 K ionizes the wind from the red giant.

  17. How Efficient Is Apis cerana (Hymenoptera: Apidae) in Pollinating Cabbage, Brassica oleracea var. capitata? Pollination Behavior, Pollinator Effectiveness, Pollinator Requirement, and Impact of Pollination.

    Science.gov (United States)

    Stanley, Johnson; Sah, Khushboo; Subbanna, Avupati Rns; Preetha, G; Gupta, JaiPrakash

    2017-06-01

    Cabbage is a cross-pollinated crop because of sporophytic self-incompatibility, and honey bees play an important role in its pollination. Though Asian honey bees, Apis cerana F., are used in pollination of cabbage, the rate of visitation, behavior, pollinator efficacy, and impact on seed-set are to be determined. Apis cerana occupy a share of 19.18% of all the flower visitors of cabbage in natural habitat of North Western Indian Himalayas. Pollination behavior in terms of peak activity, flowers processed per unit time, time spent per flower, and time spent in search of flowers are studied separately for both pollen and nectar foragers. Pollinator effectiveness as measured by seed set in flowers excluded from bee visitation, single bee visit, and unrestricted pollinator visits was 0.11. Studies on the impact of A. cerana bee pollination in cabbage seed production revealed an increase of 17.28% in siliqua per panicle, with 26.11% increase in seed yield. For assessing the requirement of A. cerana to pollinate one hectare of cabbage, flower availability and the speed with which the pollen and nectar foragers process the flowers are taken into consideration. A forager is estimated to pollinate 4,780 flowers a day, but cabbage flower requires 9.09 visits of A. cerana for optimum seed set. Thus, a maximum of 4,999 bee foragers or 8.33 colonies are needed to effectively pollinate 1 ha of cabbage. Though A. cerana is a good pollinator, our findings suggest that it is not an ideal pollinator of cabbage. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  18. Direct and Pollinator-Mediated Effects of Herbivory on Strawberry and the Potential for Improved Resistance

    Directory of Open Access Journals (Sweden)

    Anne Muola

    2017-05-01

    Full Text Available The global decline in pollinators has partly been blamed on pesticides, leading some to propose pesticide-free farming as an option to improve pollination. However, herbivores are likely to be more prevalent in pesticide-free environments, requiring knowledge of their effects on pollinators, and alternative crop protection strategies to mitigate any potential pollination reduction. Strawberry leaf beetles (SLB Galerucella spp. are important strawberry pests in Northern Europe and Russia. Given that SLB attack both leaf and flower tissue, we hypothesized pollinators would discriminate against SLB-damaged strawberry plants (Fragaria vesca, cultivar ‘Rügen’, leading to lower pollination success and yield. In addition we screened the most common commercial cultivar ‘Rügen’ and wild Swedish F. vesca genotypes for SLB resistance to assess the potential for inverse breeding to restore high SLB resistance in cultivated strawberry. Behavioral observations in a controlled experiment revealed that the local pollinator fauna avoided strawberry flowers with SLB-damaged petals. Low pollination, in turn, resulted in smaller more deformed fruits. Furthermore, SLB-damaged flowers produced smaller fruits even when they were hand pollinated, showing herbivore damage also had direct effects on yield, independent of indirect effects on pollination. We found variable resistance in wild woodland strawberry to SLB and more resistant plant genotypes than the cultivar ‘Rügen’ were identified. Efficient integrated pest management strategies should be employed to mitigate both direct and indirect effects of herbivory for cultivated strawberry, including high intrinsic plant resistance.

  19. Neither insects nor wind: ambophily in dioecious Chamaedorea palms (Arecaceae).

    Science.gov (United States)

    Rios, L D; Fuchs, E J; Hodel, D R; Cascante-Marín, A

    2014-07-01

    Pollination of Neotropical dioecious trees is commonly related to generalist insects. Similar data for non-tree species with separated genders are inconclusive. Recent studies on pollination of dioecious Chamaedorea palms (Arecaceae) suggest that species are either insect- or wind-pollinated. However, the wide variety of inflorescence and floral attributes within the genus suggests mixed pollination mode involving entomophily and anemophily. To evaluate this hypothesis, we studied the pollination of Chamaedorea costaricana, C. macrospadix, C. pinnatifrons and C. tepejilote in two montane forests in Costa Rica. A complementary morphological analysis of floral traits was carried out to distinguish species groups within the genus according to their most probable pollination mechanism. We conducted pollinator exclusion experiments, field observations on visitors to pistillate and staminate inflorescences, and trapped airborne pollen. A cluster analysis using 18 floral traits selected for their association with wind and insect pollination syndromes was carried out using 52 Chamaedorea species. Exclusion experiments showed that both wind and insects, mostly thrips (Thysanoptera), pollinated the studied species. Thrips used staminate inflorescences as brood sites and pollinated pistillate flowers by deception. Insects caught on pistillate inflorescences transported pollen, while traps proved that pollen is wind-borne. Our empirical findings clearly suggest that pollination of dioecious Chamaedorea palms is likely to involve both insects and wind. A cluster analysis showed that the majority of studied species have a combination of floral traits that allow for both pollination modes. Our pollination experiments and morphological analysis both suggest that while some species may be completely entomophilous or anemophilous, ambophily might be a common condition within Chamaedorea. Our results propose a higher diversity of pollination mechanisms of Neotropical dioecious

  20. Pollination ecology of Isoglossa woodii, a long-lived, synchronously monocarpic herb from coastal forests in South Africa.

    Science.gov (United States)

    Griffiths, M E; Tsvuura, Z; Franklin, D C; Lawes, M J

    2010-05-01

    Synchronous monocarpy in long-lived plants is often associated with pollination by wind, in part because infrequent mass flowering may satiate pollinators. Selfing in synchronous monocarps may provide reproductive assurance but conflict with the benefits of outcrossing, a key evolutionary driver of synchrony. We predicted that animal-pollinated species with synchronous flowering would have unspecialised flowers and attract abundant generalised pollinators, but predictions for selfing and outcrossing frequencies were not obvious. We examined the pollination biology of Isoglossa woodii (Acanthaceae), an insect-pollinated, monocarpic herb that flowers synchronously at 4-7-year intervals. The most frequent visitor to I. woodii flowers was the African honeybee, Apis mellifera adansonii. Hand-pollination failed to enhance seed production, indicating that the pollinators were not saturated. No seed was set in the absence of pollinators. Seed set was similar among selfed and outcrossed flowers, demonstrating a geitonogamous mixed-mating strategy with no direct evidence of preferential outcrossing. Flowers contained four ovules, but most fruits only developed one seed, raising the possibility that preferential outcrossing occurs by post-pollination processes. We argue that a number of the theoretical concerns about geitonogamous selfing as a form of reproductive assurance do not apply to a long-lived synchronous monocarp such as I. woodii.

  1. Effects of a Possible Pollinator Crisis on Food Crop Production in Brazil.

    Science.gov (United States)

    Novais, Samuel M A; Nunes, Cássio A; Santos, Natália B; D Amico, Ana R; Fernandes, G Wilson; Quesada, Maurício; Braga, Rodrigo F; Neves, Ana Carolina O

    2016-01-01

    Animal pollinators contribute to human food production and security thereby ensuring an important component of human well-being. The recent decline of these agents in Europe and North America has aroused the concern of a potential global pollinator crisis. In order to prioritize efforts for pollinator conservation, we evaluated the extent to which food production depends on animal pollinators in Brazil-one of the world's agriculture leaders-by comparing cultivated area, produced volume and yield value of major food crops that are pollinator dependent with those that are pollinator non-dependent. In addition, we valued the ecosystem service of pollination based on the degree of pollinator dependence of each crop and the consequence of a decline in food production to the Brazilian Gross Domestic Product and Brazilian food security. A total of 68% of the 53 major food crops in Brazil depend to some degree on animals for pollination. Pollinator non-dependent crops produce a greater volume of food, mainly because of the high production of sugarcane, but the cultivated area and monetary value of pollinator dependent crops are higher (59% of total cultivated area and 68% of monetary value). The loss of pollination services for 29 of the major food crops would reduce production by 16.55-51 million tons, which would amount to 4.86-14.56 billion dollars/year, and reduce the agricultural contribution to the Brazilian GDP by 6.46%- 19.36%. These impacts would be largely absorbed by family farmers, which represent 74.4% of the agricultural labor force in Brazil. The main effects of a pollinator crisis in Brazil would be felt by the poorer and more rural classes due to their lower income and direct or exclusive dependence on this ecosystem service.

  2. Sterile flowers increase pollinator attraction and promote female success in the Mediterranean herb Leopoldia comosa

    Science.gov (United States)

    Morales, Carolina L.; Traveset, Anna; Harder, Lawrence D.

    2013-01-01

    Background and Aims Large floral displays have opposing consequences for animal-pollinated angiosperms: they attract more pollinators but also enable elevated among-flower self-pollination (geitonogamy). The presence of sterile flowers as pollinator signals may enhance attraction while allowing displays of fewer open fertile flowers, limiting geitonogamy. The simultaneous contributions of fertile and non-fertile display components to pollinator attraction and reproductive output remain undetermined. Methods The simultaneous effects of the presence of sterile flowers and fertile-flower display size in two populations of Leopoldia comosa were experimentally assessed. Pollinator behaviour, pollen removal and deposition, and fruit and seed production were compared between intact plants and plants with sterile flowers removed. Key Results The presence of sterile flowers almost tripled pollinator attraction, supplementing the positive effect of the number of fertile flowers on the number of bees approaching inflorescences. Although attracted bees visited more flowers on larger inflorescences, the number visited did not additionally depend on the presence of sterile flowers. The presence of sterile flowers improved all aspects of plant performance, the magnitude of plant benefit being context dependent. During weather favourable to pollinators, the presence of sterile flowers increased pollen deposition on stigmas of young flowers, but this difference was not evident in older flowers, probably because of autonomous self-pollination in poorly visited flowers. Total pollen receipt per stigma decreased with increasing fertile display size. In the population with more pollinators, the presence of sterile flowers increased fruit number but not seed set or mass, whereas in the other population sterile flowers enhanced seeds per fruit, but not fruit production. These contrasts are consistent with dissimilar cross-pollination and autonomous self-pollination, coupled with the

  3. Requirements for plant coexistence through pollination niche partitioning

    Science.gov (United States)

    Benadi, Gita

    2015-01-01

    Plant–pollinator interactions are often thought to have been a decisive factor in the diversification of flowering plants, but to be of little or no importance for the maintenance of existing plant diversity. In a recent opinion paper, Pauw (2013 Trends Ecol. Evol. 28, 30–37. (doi:10.1016/j.tree.2012.07.019)) challenged this view by proposing a mechanism of diversity maintenance based on pollination niche partitioning. In this article, I investigate under which conditions the mechanism suggested by Pauw can promote plant coexistence, using a mathematical model of plant and pollinator population dynamics. Numerical simulations show that this mechanism is most effective when the costs of searching for flowers are low, pollinator populations are strongly limited by resources other than pollen and nectar, and plant–pollinator interactions are sufficiently specialized. I review the empirical literature on these three requirements, discuss additional factors that may be important for diversity maintenance through pollination niche partitioning, and provide recommendations on how to detect this coexistence mechanism in natural plant communities. PMID:26108627

  4. Pollination in Jacaranda rugosa (Bignoniaceae): euglossine pollinators, nectar robbers and low fruit set.

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    Milet-Pinheiro, P; Schlindwein, C

    2009-03-01

    Nectar robbers access floral nectar in illegitimate flower visits without, in general, performing a pollination service. Nevertheless, their effect on fruit set can be indirectly positive if the nectar removal causes an incremental increase in the frequency of legitimate flower visits of effective pollinators, especially in obligate outcrossers. We studied pollination and the effect of nectar robbers on the reproductive fitness of Jacaranda rugosa, an endemic shrub of the National Park of Catimbau, in the Caatinga of Pernambuco, Brazil. Xenogamous J. rugosa flowers continuously produced nectar during the day at a rate of 1 mul.h(-1). Female and male Euglossa melanotricha were the main pollinators. Early morning flower visits substantially contributed to fruit set because stigmas with open lobes were almost absent in the afternoon. Ninety-nine per cent of the flowers showed damage caused by nectar robbers. Artificial addition of sugar water prolonged the duration of flower visits of legitimate flower visitors. Removal of nectar, simulating the impact of nectar robbers, resulted in shorter flower visits of euglossine bees. While flower visits of nectar-robbing carpenter bees (Xylocopa frontalis, X. grisescens, X. ordinaria) produced only a longitudinal slit in the corolla tube in the region of the nectar chamber, worker bees of Trigona spinipes damaged the gynoecium in 92% of the flowers. This explains the outstandingly low fruit set (1.5%) of J. rugosa in the National Park of Catimbau.

  5. Courgette Production: Pollination Demand, Supply, and Value.

    Science.gov (United States)

    Knapp, Jessica L; Osborne, Juliet L

    2017-10-01

    Courgette (Cucurbita pepo L.) production in the United Kingdom is estimated to be worth £6.7 million. However, little is known about this crop's requirement for insect-mediated pollination (pollinator dependence) and if pollinator populations in a landscape are able to fulfil its pollination needs (pollination deficit). Consequently, pollination experiments were conducted over 2 yr to explore pollinator dependence and pollination deficit in field-grown courgette in the United Kingdom. Results showed that pollination increased yield by 39% and there was no evidence of pollination limitation on crop yield. This was evidenced by a surprisingly low pollination deficit (of just 3%) and no statistical difference in yield (length grown, circumference, and weight) between open- and hand-pollinated crops. Nonetheless, the high economic value of courgettes means that reducing even the small pollination deficit could still increase profit by ∼£166/ha. Interestingly, 56% of fruit was able to reach marketable size and shape without any pollination. Understanding a crop's requirement for pollinators can aid growers in their decision-making about what varieties and sites should be used. In doing so, they may increase their agricultural resilience and further their economic advantage. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America.

  6. Pollination Services at Risk: Asian Dust Poses a Threat on Pollinators' Navigation

    Science.gov (United States)

    Cho, Y.

    2016-12-01

    Beijing was hit by a massive sandstorm, which is known as Asian dust or Yellow sand phenomenon in April 2015. The city was enveloped by sand, and the reported visibility was less than 1 km. People could neither work outside nor drive. But can bees forage for their food in this sandy air? The hypothesis in this proposed study is as follows: honey bee (Apis mellifera)'s foraging activity is impeded when Asian dust is severe since the particulate matters dusted on flowers prevent the bees from noticing the ultraviolet marking of the flowers. In an experimental study, flowers dusted with PM 10 showed no specific ultraviolet nectar guides as they do in clear weather. The transport of sand and dust by wind is a powerful erosional force, fills the atmosphere with suspended dust aerosols. The dust, in the atmospheric science, generally refers to solid inorganic particles that can be readily suspended by wind. Once the bees fail to forage as this study hypothesized, they will starve to death, then plant-pollinator interaction will be threatened. Failure of bees' activity can result in loss of pollination services which could significantly affect the maintenance of the ecosystem stability as a whole. Though this research specifically studies the Asian phenomenon, it should be understood in a global context since the dust is believed to be transported one full circuit around the globe.

  7. Multiple criteria for evaluating pollinator performance in highbush blueberry (Ericales: Ericaceae) agroecosystems.

    Science.gov (United States)

    Rogers, Shelley R; Tarpy, David R; Burrack, Hannah J

    2013-12-01

    Numerous bee species provide pollination services in agricultural ecosystems. Evaluating a pollinator's performance with regard to a crop is an important step in attributing pollination services and predicting how changes in a bee community or foraging environment will affect those services. We used multiple criteria to evaluate pollinators of North Carolina highbush blueberry, Vaccinium corymbosum L., agroecosystems. For five groups of bees (Apis mellifera L., Bombus spp., Habropoda laboriosa F., small native bees, and Xylocopa virginica L.), we measured forager abundance through transect observations, quantified per-visit efficiency as viable seed set resulting from a single visit, and analyzed bee presence in different weather conditions. We also considered two other criteria affecting pollinator performance-visitation rate and interspecific influence. A. mellifera was the most abundant bee in the majority of our survey sites, yet had low per-visit efficiency and reduced foraging activity in inclement weather. Small native bees were highly efficient pollinators. Their visits resulted in nearly twice as many seeds as A. mellifera or H. laboriosa. Bombus spp., H. laboriosa, and small native bees were more resilient to fluctuations in temperature, wind speed, and solar radiation than A. mellifera. Although nectar-robbing X. virginica contributed to little pollination through direct flower visits, their presence within the crop impacts the behavior and performance of other individuals. Underscoring the importance of evaluating pollinator performance via multiple criteria, our results show that bee groups contribute to pollination in different ways. These differences may provide functional complementarity and stability of pollination services to agricultural systems.

  8. Constraints imposed by pollinator behaviour on the ecology and evolution of plant mating systems.

    Science.gov (United States)

    Devaux, C; Lepers, C; Porcher, E

    2014-07-01

    Most flowering plants rely on pollinators for their reproduction. Plant-pollinator interactions, although mutualistic, involve an inherent conflict of interest between both partners and may constrain plant mating systems at multiple levels: the immediate ecological plant selfing rates, their distribution in and contribution to pollination networks, and their evolution. Here, we review experimental evidence that pollinator behaviour influences plant selfing rates in pairs of interacting species, and that plants can modify pollinator behaviour through plastic and evolutionary changes in floral traits. We also examine how theoretical studies include pollinators, implicitly or explicitly, to investigate the role of their foraging behaviour in plant mating system evolution. In doing so, we call for more evolutionary models combining ecological and genetic factors, and additional experimental data, particularly to describe pollinator foraging behaviour. Finally, we show that recent developments in ecological network theory help clarify the impact of community-level interactions on plant selfing rates and their evolution and suggest new research avenues to expand the study of mating systems of animal-pollinated plant species to the level of the plant-pollinator networks. © 2014 The Authors. Journal of Evolutionary Biology © 2014 European Society For Evolutionary Biology.

  9. Identifying pollination service hotspots and coldspots using citizen science data from the Great Sunflower Project

    Science.gov (United States)

    LeBuhn, G.; Schmucki, R.

    2016-12-01

    Identifying the spatial patterns of pollinator visitation rates is key to identifying the drivers of differences in pollination service and the areas where pollinator conservation will provide the highest return on investment. However, gathering pollinator abundance data at the appropriate regional and national scales is untenable. As a surrogate, habitat models have been developed to identify areas of pollinator losses but these models have been developed using expert opinion based on foraging and nesting requirements. Thousands of citizen scientists across the United States participating in The Great Sunflower Project (www.GreatSunflower.org) contribute timed counts of pollinator visits to a focal sunflower variety planted in local gardens and green spaces. While these data provide a more direct measure of pollination service to a standardized plant and include a measure of effort, the data are complicated. Each location is sampled at different dates, times and frequencies as well as different points across the local flight season. To overcome this complication, we have used a generalized additive model to generate regional flight curves to calibrate each individual data point and to attain better estimates of pollination service at each site. Using these flight season corrected data, we identify hotspots and cold spots in pollinator service across the United States, evaluate the drivers shaping the spatial patterns and observe how these data align with the results obtained from predictive models that are based on expert knowledge on foraging and nesting habitats.

  10. Create a pollinator garden at your nursery: An emphasis on monarch butterflies

    Science.gov (United States)

    Thomas D. Landis; R. Kasten Dumroese; Matthew E. Horning

    2014-01-01

    We realize that this type of article is a departure for FNN readers but feel that it is important for forest, conservation, and native plant nurseries to be good environmental stewards. In addition, establishing a pollinator garden at your nursery can be good for business, too. Demonstrating the role and beauty of native plants and their pollinators, particulary in a...

  11. Diverse pollinator communities enhance plant reproductive success.

    Science.gov (United States)

    Albrecht, Matthias; Schmid, Bernhard; Hautier, Yann; Müller, Christine B

    2012-12-07

    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, indicating a niche complementarity among these pollinator groups. Our study demonstrates enhanced pollination services of diverse pollinator communities at the plant population level and suggests that both the niche complementarity and the presence of specific taxa in a pollinator community drive this positive relationship.

  12. Pollination ecology of the Gray Nicker Caesalpinia crista (Caesalpiniaceae a mangrove associate at Coringa Mangrove Forest, Andhra Pradesh, India

    Directory of Open Access Journals (Sweden)

    P.S. Raju

    2014-09-01

    Full Text Available Caesalpinia crista L., commanly known as Gray Nicker, is an oligohaline mangrove associate confined to landward marginal areas of the Coringa Mangrove Forest, Andhra Pradesh, India. The flowering occurs during the wet season from June to November. The flowers are hermaphroditic, self-compatible and exhibit a mixed breeding system. The floral characteristics that constitute melittophilous pollination syndrome include diurnal anthesis, slight fragrance, zygomorphy, yellow petals, with a flag petal displaying a conspicuous nectar guide, and the presence of nectar with a high sugar concentration. Extra-floral nectar along the rachis is an additional attractant and is easily perceivable by bees. The plant is pollinated almost exclusively by bees, especially carpenter bees. The floral characteristics such as free petals, fully exposed stamens with dry and powdery pollen grains and hairy stigma facilitate anemophily which is effective due to high winds during the rainy season. The prolific growth and near synchronous flowering at population level contribute to pollen availability in huge quantities and enable anemophily as an effective mode of pollination. The functionality of melittophily and anemophily together constitutes ambophily. Hand-pollination experiments indicated that the plant is principally out-crossing. The natural fruit set does not exceed 10%; this lowest percentage could be partly due to flower-feeding by the beetle, Mylabris phalerata. The fruits are indehiscent, 1-seeded, which are buoyant and are not dispersed far away from the parental sites. The viable seeds produce new plants in the vicinity of parental plants during the rainy season. This plant builds up its population as small patches or in pure stands and hence is important in building landward mangrove cover.

  13. Pollination of Australian Macrozamia cycads (Zamiaceae): effectiveness and behavior of specialist vectors in a dependent mutualism.

    Science.gov (United States)

    Terry, L Irene; Walter, Gimme H; Donaldson, John S; Snow, Elizabeth; Forster, Paul I; Machin, Peter J

    2005-06-01

    Complementary field and laboratory tests confirmed and quantified the pollination abilities of Tranes sp. weevils and Cycadothrips chadwicki thrips, specialist insects of their respective cycad hosts, Macrozamia machinii and M. lucida. No agamospermous seeds were produced when both wind and insects were excluded from female cones; and the exclusion of wind-vectored pollen alone did not eliminate seed set, because insects were able to reach the cone. Based on enclosure pollination tests, each weevil pollinates an average 26.2 ovules per cone and each thrips 2.4 ovules per cone. These pollinators visited similar numbers of ovules per cone in fluorescent dye tests that traced insect movement through cones. Fluorescent dye granules deposited by Cycadothrips were concentrated around the micropyle of each visited ovule, the site of pollen droplet release, where pollen must be deposited to achieve pollination. In contrast, Tranes weevils left dye scattered on different areas of each visited ovule, indicating that chance plays a greater role in this system. Each weevil and 25 thrips delivered 6.2 and 5.2 pollen grains, respectively, on average, to each visited ovule per cone, based on examination of dissected pollen canals. In sum, the pollination potential of 25 Cycadothrips approximates that of one Tranes weevil.

  14. A quantitative review of pollination syndromes: do floral traits predict effective pollinators?

    Science.gov (United States)

    Rosas-Guerrero, Víctor; Aguilar, Ramiro; Martén-Rodríguez, Silvana; Ashworth, Lorena; Lopezaraiza-Mikel, Martha; Bastida, Jesús M; Quesada, Mauricio

    2014-03-01

    The idea of pollination syndromes has been largely discussed but no formal quantitative evaluation has yet been conducted across angiosperms. We present the first systematic review of pollination syndromes that quantitatively tests whether the most effective pollinators for a species can be inferred from suites of floral traits for 417 plant species. Our results support the syndrome concept, indicating that convergent floral evolution is driven by adaptation to the most effective pollinator group. The predictability of pollination syndromes is greater in pollinator-dependent species and in plants from tropical regions. Many plant species also have secondary pollinators that generally correspond to the ancestral pollinators documented in evolutionary studies. We discuss the utility and limitations of pollination syndromes and the role of secondary pollinators to understand floral ecology and evolution. © 2014 John Wiley & Sons Ltd/CNRS.

  15. Extreme divergence in floral scent among woodland star species (Lithophragma spp.) pollinated by floral parasites.

    Science.gov (United States)

    Friberg, Magne; Schwind, Christopher; Raguso, Robert A; Thompson, John N

    2013-04-01

    A current challenge in coevolutionary biology is to understand how suites of traits vary as coevolving lineages diverge. Floral scent is often a complex, variable trait that attracts a suite of generalized pollinators, but may be highly specific in plants specialized on attracting coevolved pollinating floral parasites. In this study, floral scent variation was investigated in four species of woodland stars (Lithophragma spp.) that share the same major pollinator (the moth Greya politella, a floral parasite). Three specific hypotheses were tested: (1) sharing the same specific major pollinator favours conservation of floral scent among close relatives; (2) selection favours 'private channels' of rare compounds particularly aimed at the specialist pollinator; or (3) selection from rare, less-specialized co-pollinators mitigates the conservation of floral scent and occurrence of private channels. Dynamic headspace sampling and solid-phase microextraction were applied to greenhouse-grown plants from a common garden as well as to field samples from natural populations in a series of experiments aiming to disentangle the genetic and environmental basis of floral scent variation. Striking floral scent divergence was discovered among species. Only one of 69 compounds was shared among all four species. Scent variation was largely genetically based, because it was consistent across field and greenhouse treatments, and was not affected by visits from the pollinating floral parasite. The strong divergence in floral scents among Lithophragma species contrasts with the pattern of conserved floral scent composition found in other plant genera involved in mutualisms with pollinating floral parasites. Unlike some of these other obligate pollination mutualisms, Lithophragma plants in some populations are occasionally visited by generalist pollinators from other insect taxa. This additional complexity may contribute to the diversification in floral scent found among the Lithophragma

  16. Identification of major quantitative trait loci underlying floral pollination syndrome divergence in Penstemon.

    Science.gov (United States)

    Wessinger, Carolyn A; Hileman, Lena C; Rausher, Mark D

    2014-08-05

    Distinct floral pollination syndromes have emerged multiple times during the diversification of flowering plants. For example, in western North America, a hummingbird pollination syndrome has evolved more than 100 times, generally from within insect-pollinated lineages. The hummingbird syndrome is characterized by a suite of floral traits that attracts and facilitates pollen movement by hummingbirds, while at the same time discourages bee visitation. These floral traits generally include large nectar volume, red flower colour, elongated and narrow corolla tubes and reproductive organs that are exerted from the corolla. A handful of studies have examined the genetic architecture of hummingbird pollination syndrome evolution. These studies find that mutations of relatively large effect often explain increased nectar volume and transition to red flower colour. In addition, they suggest that adaptive suites of floral traits may often exhibit a high degree of genetic linkage, which could facilitate their fixation during pollination syndrome evolution. Here, we explore these emerging generalities by investigating the genetic basis of floral pollination syndrome divergence between two related Penstemon species with different pollination syndromes--bee-pollinated P. neomexicanus and closely related hummingbird-pollinated P. barbatus. In an F2 mapping population derived from a cross between these two species, we characterized the effect size of genetic loci underlying floral trait divergence associated with the transition to bird pollination, as well as correlation structure of floral trait variation. We find the effect sizes of quantitative trait loci for adaptive floral traits are in line with patterns observed in previous studies, and find strong evidence that suites of floral traits are genetically linked. This linkage may be due to genetic proximity or pleiotropic effects of single causative loci. Interestingly, our data suggest that the evolution of floral traits

  17. Pollinators show flower colour preferences but flowers with similar colours do not attract similar pollinators.

    Science.gov (United States)

    Reverté, Sara; Retana, Javier; Gómez, José M; Bosch, Jordi

    2016-08-01

    Colour is one of the main floral traits used by pollinators to locate flowers. Although pollinators show innate colour preferences, the view that the colour of a flower may be considered an important predictor of its main pollinators is highly controversial because flower choice is highly context-dependent, and initial innate preferences may be overridden by subsequent associative learning. Our objective is to establish whether there is a relationship between flower colour and pollinator composition in natural communities. We measured the flower reflectance spectrum and pollinator composition in four plant communities (85 plant species represented by 109 populations, and 32 305 plant-pollinator interactions in total). Pollinators were divided into six taxonomic groups: bees, ants, wasps, coleopterans, dipterans and lepidopterans. We found consistent associations between pollinator groups and certain colours. These associations matched innate preferences experimentally established for several pollinators and predictions of the pollination syndrome theory. However, flowers with similar colours did not attract similar pollinator assemblages. The explanation for this paradoxical result is that most flower species are pollination generalists. We conclude that although pollinator colour preferences seem to condition plant-pollinator interactions, the selective force behind these preferences has not been strong enough to mediate the appearance and maintenance of tight colour-based plant-pollinator associations. © The Author 2016. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  18. Changing bee and hoverfly pollinator assemblages along an urban-rural gradient.

    Directory of Open Access Journals (Sweden)

    Adam J Bates

    Full Text Available The potential for reduced pollination ecosystem service due to global declines of bees and other pollinators is cause for considerable concern. Habitat degradation, destruction and fragmentation due to agricultural intensification have historically been the main causes of this pollinator decline. However, despite increasing and accelerating levels of global urbanization, very little research has investigated the effects of urbanization on pollinator assemblages. We assessed changes in the diversity, abundance and species composition of bee and hoverfly pollinator assemblages in urban, suburban, and rural sites across a UK city.Bees and hoverflies were trapped and netted at 24 sites of similar habitat character (churchyards and cemeteries that varied in position along a gradient of urbanization. Local habitat quality (altitude, shelter from wind, diversity and abundance of flowers, and the broader-scale degree of urbanization (e.g. percentage of built landscape and gardens within 100 m, 250 m, 500 m, 1 km, and 2.5 km of the site were assessed for each study site. The diversity and abundance of pollinators were both significantly negatively associated with higher levels of urbanization. Assemblage composition changed along the urbanization gradient with some species positively associated with urban and suburban land-use, but more species negatively so. Pollinator assemblages were positively affected by good site habitat quality, in particular the availability of flowering plants.Our results show that urban areas can support diverse pollinator assemblages, but that this capacity is strongly affected by local habitat quality. Nonetheless, in both urban and suburban areas of the city the assemblages had fewer individuals and lower diversity than similar rural habitats. The unique development histories of different urban areas, and the difficulty of assessing mobile pollinator assemblages in just part of their range, mean that complementary studies in

  19. Warming, CO2, and nitrogen deposition interactively affect a plant-pollinator mutualism.

    Science.gov (United States)

    Hoover, Shelley E R; Ladley, Jenny J; Shchepetkina, Anastasia A; Tisch, Maggie; Gieseg, Steven P; Tylianakis, Jason M

    2012-03-01

    Environmental changes threaten plant-pollinator mutualisms and their critical ecosystem service. Drivers such as land use, invasions and climate change can affect pollinator diversity or species encounter rates. However, nitrogen deposition, climate warming and CO(2) enrichment could interact to disrupt this crucial mutualism by altering plant chemistry in ways that alter floral attractiveness or even nutritional rewards for pollinators. Using a pumpkin model system, we show that these drivers non-additively affect flower morphology, phenology, flower sex ratios and nectar chemistry (sugar and amino acids), thereby altering the attractiveness of nectar to bumble bee pollinators and reducing worker longevity. Alarmingly, bees were attracted to, and consumed more, nectar from a treatment that reduced their survival by 22%. Thus, three of the five major drivers of global environmental change have previously unknown interactive effects on plant-pollinator mutualisms that could not be predicted from studies of individual drivers in isolation. © 2012 Blackwell Publishing Ltd/CNRS.

  20. Risk Analysis of Loblolly Pine Controlled Mass Pollination Program

    Science.gov (United States)

    T.D. Byram; F.E. Bridgwater

    1999-01-01

    The economic success of controlled mass pollination (CMP) depends both upon the value of the genetic gain obtained and the cost per seed. Crossing the best six loblolly pine (Pinus taeda) parents currently available in each deployment region of the Western Gulf Forest Tree Improvement Program will produce seed with an average additional gain in mean...

  1. Pollinator-prey conflicts in carnivorous plants: When flower and trap properties mean life or death.

    Science.gov (United States)

    El-Sayed, Ashraf M; Byers, John A; Suckling, David M

    2016-02-18

    Insect-pollinated carnivorous plants are expected to have higher fitness if they resolve pollinator-prey conflicts by sparing insects pollinating their flowers while trapping prey insects. We examined whether separation between flowers and traps of the carnivorous sundew species or pollinator preferences for colours of flowers enable these plants to spare pollinators. In addition, we collected odours from flowers and traps of each carnivorous species in order to identify volatile chemicals that are attractive or repellent to pollinators and prey insects. In Drosera spatulata and D. arcturi, no volatiles were detected from either their flowers or traps that could serve as kairomone attractants for insects. However, behavioural experiments indicated white colour and spatial separation between flowers and traps aid in reducing pollinator entrapment while capturing prey. In contrast, D. auriculata have flowers that are adjacent to their traps. In this species we identified chemical signals emanating from flowers that comprised an eight-component blend, while the plant's traps emitted a unique four-component blend. The floral odour attracted both pollinator and prey insects, while trap odour only attracted prey. This is the first scientific report to demonstrate that carnivorous plants utilize visual, spatial, and chemical signals to spare flower visitors while trapping prey insects.

  2. Stingless Bees as Alternative Pollinators of Canola.

    Science.gov (United States)

    Witter, Sidia; Nunes-Silva, Patrícia; Lisboa, Bruno B; Tirelli, Flavia P; Sattler, Aroni; Both Hilgert-Moreira, Suzane; Blochtein, Betina

    2015-06-01

    Alternative pollinators can ensure pollination services if the availability of the managed or most common pollinator is compromised. In this study, the behavior and pollination efficiency of Apis mellifera L. and two species of stingless bees, Plebeia emerina Friese and Tetragonisca fiebrigi Schwarz, were evaluated and compared in flowers of Brassica napus L. 'Hyola 61'. A. mellifera was an efficient pollinator when collecting nectar because it effectively touched the reproductive organs of the flower. In contrast, stingless bees were efficient pollinators only when collecting pollen. The number of pollen grains deposited on the stigma after a single visit by worker bees of the three species was greater than the number of grains resulting from pollination without the bee visits. On average, the three species deposited enough pollen grains to fertilize all of the flower ovules. A. mellifera and P. emerina had similar pollination efficiency because no significant differences were observed in the characteristics of the siliques produced. Although T. fiebrigi is also an effective pollinator, the seed mass produced by their pollination was lower. Native bees promoted similar rates of fruit set compared with A. mellifera. Thus, P. emerina has potential to be used for pollination in canola crops. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  3. Pollen analyses for pollination research, unacetolyzed pollen

    Directory of Open Access Journals (Sweden)

    Gretchen D. Jones

    2012-10-01

    Full Text Available Pollinators feed on the pollen, nectar, and other plant exudates that are associated with flowers. As a result of this feeding activity, pollen becomes attached to them. Analysis of this pollen can reveal what they eat, their dispersal patterns in and around cropping systems, and their role in pollination. However, finding pollen on and or in a pollinator depends on the technique used to recover pollen. Two very easy techniques are described in detail that have been used to recover pollen from a variety of pollinators including beneficial and harmful insects, spiders, bats, and other pollinators. These techniques can be used to recover pollen from internal tissues (gut, alimentary canal, crop, etc., external tissues (proboscis, legs, eyes, etc., or both. By using the proper technique, better pollen recovery can be made and thus better data can be obtained about the pollinators, the foods they eat, the plants they pollinate, their migration routes and source zones.

  4. Phenotypic selection on flowering phenology and pollination efficiency traits between Primula populations with different pollinator assemblages.

    Science.gov (United States)

    Wu, Yun; Li, Qing-Jun

    2017-10-01

    Floral traits have largely been attributed to phenotypic selection in plant-pollinator interactions. However, the strength of this link has rarely been ascertained with real pollinators. We conducted pollinator observations and estimated selection through female fitness on flowering phenology and floral traits between two Primula secundiflora populations. We quantified pollinator-mediated selection by subtracting estimates of selection gradients of plants receiving supplemental hand pollination from those of plants receiving open pollination. There was net directional selection for an earlier flowering start date at populations where the dominant pollinators were syrphid flies, and flowering phenology was also subjected to stabilized quadratic selection. However, a later flowering start date was significantly selected at populations where the dominant pollinators were legitimate (normal pollination through the corolla tube entrance) and illegitimate bumblebees (abnormal pollination through nectar robbing hole which located at the corolla tube), and flowering phenology was subjected to disruptive quadratic selection. Wider corolla tube entrance diameter was selected at both populations. Furthermore, the strength of net directional selection on flowering start date and corolla tube entrance diameter was stronger at the population where the dominant pollinators were syrphid flies. Pollinator-mediated selection explained most of the between-population variations in the net directional selection on flowering phenology and corolla tube entrance diameter. Our results suggested the important influence of pollinator-mediated selection on floral evolution. Variations in pollinator assemblages not only resulted in variation in the direction of selection but also the strength of selection on floral traits.

  5. Apis mellifera pollination improves agronomic productivity of anemophilous castor bean (Ricinus communis).

    Science.gov (United States)

    Rizzardo, Rômulo A G; Milfont, Marcelo O; Silva, Eva M S da; Freitas, Breno M

    2012-12-01

    Castor bean (Ricinus communis L.) is cultivated mainly for biodiesel production because of its oil-rich seeds; it is assumed to be an anemophylous species. But pollination deficit can lead to low productivity often attributed to other reasons. In this paper, we investigated pollination requirements, pollination mechanism, occurrence of pollination deficit, and the role of biotic pollinators in a large commercial plantation of castor bean. Our results show that R. communis bears a mixed breeding system favoring selfing by geitonogamy, although the wind promotes mostly outcrossing. We also found that the honey bee (Apis mellifera L.) foraging on castor bean can both transfer pollen from male to female flowers within the same raceme and boost the release of airborne pollen by male flowers. Both situations increase geitonogamy rates, raising significantly fruit set and seed yield. This is the first report of an animal foraging activity increasing seed yield in an anemophilous and geitonogamous crop and elucidates the role of biotic pollinators in castor bean reproduction.

  6. Modest enhancements to conventional grassland diversity improve the provision of pollination services.

    Science.gov (United States)

    Orford, Katherine A; Murray, Phil J; Vaughan, Ian P; Memmott, Jane

    2016-06-01

    Grassland for livestock production is a major form of land use throughout Europe and its intensive management threatens biodiversity and ecosystem functioning in agricultural landscapes. Modest increases to conventional grassland biodiversity could have considerable positive impacts on the provision of ecosystem services, such as pollination, to surrounding habitats.Using a field-scale experiment in which grassland seed mixes and sward management were manipulated, complemented by surveys on working farms and phytometer experiments, the impact of conventional grassland diversity and management on the functional diversity and ecosystem service provision of pollinator communities were investigated.Increasing plant richness, by the addition of both legumes and forbs, was associated with significant enhancements in the functional diversity of grassland pollinator communities. This was associated with increased temporal stability of flower-visitor interactions at the community level. Visitation networks revealed pasture species Taraxacum sp. ( Wigg .) (dandelion) and Cirsium arvense ( Scop .) (creeping thistle) to have the highest pollinator visitation frequency and richness. Cichorium intybus (L.) (chichory) was highlighted as an important species having both high pollinator visitation and desirable agronomic properties.Increased sward richness was associated with an increase in the pollination of two phytometer species; Fragaria  ×  ananassa (strawberry) and Silene dioica (red campion), but not Vicia faba (broad bean). Enhanced functional diversity, richness and abundance of the pollinator communities associated with more diverse neighbouring pastures were found to be potential mechanisms for improved pollination. Synthesis and applications . A modest increase in conventional grassland plant diversity with legumes and forbs, achievable with the expertise and resources available to most grassland farmers, could enhance pollinator functional diversity, richness and

  7. Native bees and plant pollination

    Science.gov (United States)

    Ginsberg, H.S.

    2004-01-01

    Bees are important pollinators, but evidence suggests that numbers of some species are declining. Decreases have been documented in the honey bee, Apis mellifera (which was introduced to North America), but there are no monitoring programs for the vast majority of native species, so we cannot be sure about the extent of this problem. Recent efforts to develop standardized protocols for bee sampling will help us collect the data needed to assess trends in bee populations. Unfortunately, diversity of bee life cycles and phenologies, and the large number of rare species, make it difficult to assess trends in bee faunas. Changes in bee populations can affect plant reproduction, which can influence plant population density and cover, thus potentially modifying horizontal and vertical structure of a community, microclimate near the ground, patterns of nitrogen deposition, etc. These potential effects of changes in pollination patterns have not been assessed in natural communities. Effects of management actions on bees and other pollinators should be considered in conservation planning.

  8. Pollinator population size and pollination ecosystem service responses to enhancing floral and nesting resources

    OpenAIRE

    H?ussler, Johanna; Sahlin, Ullrika; Baey, Charlotte; Smith, Henrik G.; Clough, Yann

    2017-01-01

    Abstract Modeling pollination ecosystem services requires a spatially explicit, process?based approach because they depend on both the behavioral responses of pollinators to the amount and spatial arrangement of habitat and on the within? and between?season dynamics of pollinator populations in response to land use. We describe a novel pollinator model predicting flower visitation rates by wild central?place foragers (e.g., nesting bees) in spatially explicit landscapes. The model goes beyond...

  9. Honey bees as pollinators in natural communities

    OpenAIRE

    Kingston, Jennifer Marie

    2017-01-01

    Honey bees are the most widespread pollinating animal species in natural plant communities worldwide, and in San Diego, California, despite high native bee diversity, the introduced honey bee is responsible for over 75% of flower visits. We performed a) a meta-analysis of published studies which report the per-visit efficiency of honey bees as pollinators relative to other floral visitors and b) a field survey documenting seasonal change in floral abundances and pollinator visitation in a co...

  10. Pollination biology of fruit-bearing hedgerow plants and the role of flower-visiting insects in fruit-set

    Science.gov (United States)

    Jacobs, Jennifer H.; Clark, Suzanne J.; Denholm, Ian; Goulson, Dave; Stoate, Chris; Osborne, Juliet L.

    2009-01-01

    Background and Aims In the UK, the flowers of fruit-bearing hedgerow plants provide a succession of pollen and nectar for flower-visiting insects for much of the year. The fruits of hedgerow plants are a source of winter food for frugivorous birds on farmland. It is unclear whether recent declines in pollinator populations are likely to threaten fruit-set and hence food supply for birds. The present study investigates the pollination biology of five common hedgerow plants: blackthorn (Prunus spinosa), hawthorn (Crataegus monogyna), dog rose (Rosa canina), bramble (Rubus fruticosus) and ivy (Hedera helix). Methods The requirement for insect pollination was investigated initially by excluding insects from flowers by using mesh bags and comparing immature and mature fruit-set with those of open-pollinated flowers. Those plants that showed a requirement for insect pollination were then tested to compare fruit-set under two additional pollination service scenarios: (1) reduced pollination, with insects excluded from flowers bagged for part of the flowering period, and (2) supplemental pollination, with flowers hand cross-pollinated to test for pollen limitation. Key Results The proportions of flowers setting fruit in blackthorn, hawthorn and ivy were significantly reduced when insects were excluded from flowers by using mesh bags, whereas fruit-set in bramble and dog rose were unaffected. Restricting the exposure of flowers to pollinators had no significant effect on fruit-set. However, blackthorn and hawthorn were found to be pollen-limited, suggesting that the pollination service was inadequate in the study area. Conclusions Ensuring strong populations of insect pollinators may be essential to guarantee a winter fruit supply for birds in UK hedgerows. PMID:19770165

  11. Pollination biology of fruit-bearing hedgerow plants and the role of flower-visiting insects in fruit-set.

    Science.gov (United States)

    Jacobs, Jennifer H; Clark, Suzanne J; Denholm, Ian; Goulson, Dave; Stoate, Chris; Osborne, Juliet L

    2009-12-01

    In the UK, the flowers of fruit-bearing hedgerow plants provide a succession of pollen and nectar for flower-visiting insects for much of the year. The fruits of hedgerow plants are a source of winter food for frugivorous birds on farmland. It is unclear whether recent declines in pollinator populations are likely to threaten fruit-set and hence food supply for birds. The present study investigates the pollination biology of five common hedgerow plants: blackthorn (Prunus spinosa), hawthorn (Crataegus monogyna), dog rose (Rosa canina), bramble (Rubus fruticosus) and ivy (Hedera helix). The requirement for insect pollination was investigated initially by excluding insects from flowers by using mesh bags and comparing immature and mature fruit-set with those of open-pollinated flowers. Those plants that showed a requirement for insect pollination were then tested to compare fruit-set under two additional pollination service scenarios: (1) reduced pollination, with insects excluded from flowers bagged for part of the flowering period, and (2) supplemental pollination, with flowers hand cross-pollinated to test for pollen limitation. The proportions of flowers setting fruit in blackthorn, hawthorn and ivy were significantly reduced when insects were excluded from flowers by using mesh bags, whereas fruit-set in bramble and dog rose were unaffected. Restricting the exposure of flowers to pollinators had no significant effect on fruit-set. However, blackthorn and hawthorn were found to be pollen-limited, suggesting that the pollination service was inadequate in the study area. Ensuring strong populations of insect pollinators may be essential to guarantee a winter fruit supply for birds in UK hedgerows.

  12. Bombus huntii, Bombus impatiens, and Bombus vosnesenskii (Hymenoptera: Apidae) Pollinate Greenhouse-Grown Tomatoes in Western North America.

    Science.gov (United States)

    Strange, James P

    2015-06-01

    Bumble bees (Bombus) are the primary pollinators of tomatoes grown in greenhouses and can significantly increase fruit weight compared with tomatoes that receive no supplemental pollination. More than a million colonies are sold worldwide annually to meet pollination needs. Due to mounting concerns over the transportation of bumble bees outside of their native ranges, several species native to western North American are currently being investigated as potential commercial pollinators. Here, two western, Bombus huntii Greene and Bombus vosnesenskii Radoszkowski, and one eastern species, Bombus impatiens Cresson, are compared for their efficacy as pollinators of greenhouse-grown tomatoes. In two experiments, colonies were placed in greenhouses and compared with control plants that received no supplemental pollination. In the first experiment, seed set was significantly increased with B. huntii pollination in one variety of cherry tomatoes. In the second experiment comparing all three bumble bee species, fruit weight was an average of 25.2 g heavier per fruit pollinated by bees versus the control, and the number of days to harvest was 2.9 d shorter for bee-pollinated fruit. In some rounds of pollination, differences were found among bumble bee species, but these were inconsistent across replicates and not statistically significant overall. Additionally, fruit weight was shown to be highly correlated to fruit diameter and seed set in all tests and, thus, is shown to be a reliable metric for assessing pollination in future studies. These results suggest that commercialization of western bumble bees is a viable alternative to the current practices of moving of nonnative bees into western North America to pollinate tomatoes. Published by Oxford University Press on behalf of Entomological Society of America 2015. This work is written by a US Government employee and is in the public domain in the US.

  13. Landscape effects on pollinator communities and pollination services in small-holder agroecosystems

    NARCIS (Netherlands)

    Zou, Yi; Bianchi, Felix J.J.A.; Jauker, Frank; Xiao, Haijun; Chen, Junhui; Cresswell, James; Luo, Shudong; Huang, Jikun; Deng, Xiangzheng; Hou, Lingling; Werf, van der Wopke

    2017-01-01

    Pollination by insects is key for the productivity of many fruit and non-graminous seed crops, but little is known about the response of pollinators to landscapes dominated by small-holder agriculture. Here we assess the relationships between landscape context, pollinator communities (density and

  14. Interactive effects among ecosystem services and management practices on crop production: Pollination in coffee agroforestry systems

    Science.gov (United States)

    Boreux, Virginie; Kushalappa, Cheppudira G.; Vaast, Philippe; Ghazoul, Jaboury

    2013-01-01

    Crop productivity is improved by ecosystem services, including pollination, but this should be set in the context of trade-offs among multiple management practices. We investigated the impact of pollination services on coffee production, considering variation in fertilization, irrigation, shade cover, and environmental variables such as rainfall (which stimulates coffee flowering across all plantations), soil pH, and nitrogen availability. After accounting for management interventions, bee abundance improved coffee production (number of berries harvested). Some management interventions, such as irrigation, used once to trigger asynchronous flowering, dramatically increased bee abundance at coffee trees. Others, such as the extent and type of tree cover, revealed interacting effects on pollination and, ultimately, crop production. The effects of management interventions, notably irrigation and addition of lime, had, however, far more substantial positive effects on coffee production than tree cover. These results suggest that pollination services matter, but managing the asynchrony of flowering was a more effective tool for securing good pollination than maintaining high shade tree densities as pollinator habitat. Complex interactions across farm and landscape scales, including both management practices and environmental conditions, shape pollination outcomes. Effective production systems therefore require the integrated consideration of management practices in the context of the surrounding habitat structure. This paper points toward a more strategic use of ecosystem services in agricultural systems, where ecosystem services are shaped by the coupling of management interventions and environmental variables. PMID:23671073

  15. A role for parasites in stabilising the fig-pollinator mutualism.

    Directory of Open Access Journals (Sweden)

    Derek W Dunn

    2008-03-01

    Full Text Available Mutualisms are interspecific interactions in which both players benefit. Explaining their maintenance is problematic, because cheaters should outcompete cooperative conspecifics, leading to mutualism instability. Monoecious figs (Ficus are pollinated by host-specific wasps (Agaonidae, whose larvae gall ovules in their "fruits" (syconia. Female pollinating wasps oviposit directly into Ficus ovules from inside the receptive syconium. Across Ficus species, there is a widely documented segregation of pollinator galls in inner ovules and seeds in outer ovules. This pattern suggests that wasps avoid, or are prevented from ovipositing into, outer ovules, and this results in mutualism stability. However, the mechanisms preventing wasps from exploiting outer ovules remain unknown. We report that in Ficus rubiginosa, offspring in outer ovules are vulnerable to attack by parasitic wasps that oviposit from outside the syconium. Parasitism risk decreases towards the centre of the syconium, where inner ovules provide enemy-free space for pollinator offspring. We suggest that the resulting gradient in offspring viability is likely to contribute to selection on pollinators to avoid outer ovules, and by forcing wasps to focus on a subset of ovules, reduces their galling rates. This previously unidentified mechanism may therefore contribute to mutualism persistence independent of additional factors that invoke plant defences against pollinator oviposition, or physiological constraints on pollinators that prevent oviposition in all available ovules.

  16. A question of data quality-Testing pollination syndromes in Balsaminaceae.

    Science.gov (United States)

    Abrahamczyk, Stefan; Lozada-Gobilard, Sissi; Ackermann, Markus; Fischer, Eberhard; Krieger, Vera; Redling, Almut; Weigend, Maximilian

    2017-01-01

    Pollination syndromes and their predictive power regarding actual plant-animal interactions have been controversially discussed in the past. We investigate pollination syndromes in Balsaminaceae, utilizing quantitative respectively categorical data sets of flower morphometry, signal and reward traits for 86 species to test for the effect of different types of data on the test patterns retrieved. Cluster Analyses of the floral traits are used in combination with independent pollinator observations. Based on quantitative data we retrieve seven clusters, six of them corresponding to plausible pollination syndromes and one additional, well-supported cluster comprising highly divergent floral architectures. This latter cluster represents a non-syndrome of flowers not segregated by the specific data set here used. Conversely, using categorical data we obtained only a rudimentary resolution of pollination syndromes, in line with several earlier studies. The results underscore that the use of functional, exactly quanitified trait data has the power to retrieve pollination syndromes circumscribed by the specific data used. Data quality can, however, not be replaced by sheer data volume. With this caveat, it is possible to identify pollination syndromes from large datasets and to reliably extrapolate them for taxa for which direct observations are unavailable.

  17. A question of data quality—Testing pollination syndromes in Balsaminaceae

    Science.gov (United States)

    Lozada-Gobilard, Sissi; Ackermann, Markus; Fischer, Eberhard; Krieger, Vera; Redling, Almut; Weigend, Maximilian

    2017-01-01

    Pollination syndromes and their predictive power regarding actual plant-animal interactions have been controversially discussed in the past. We investigate pollination syndromes in Balsaminaceae, utilizing quantitative respectively categorical data sets of flower morphometry, signal and reward traits for 86 species to test for the effect of different types of data on the test patterns retrieved. Cluster Analyses of the floral traits are used in combination with independent pollinator observations. Based on quantitative data we retrieve seven clusters, six of them corresponding to plausible pollination syndromes and one additional, well-supported cluster comprising highly divergent floral architectures. This latter cluster represents a non-syndrome of flowers not segregated by the specific data set here used. Conversely, using categorical data we obtained only a rudimentary resolution of pollination syndromes, in line with several earlier studies. The results underscore that the use of functional, exactly quanitified trait data has the power to retrieve pollination syndromes circumscribed by the specific data used. Data quality can, however, not be replaced by sheer data volume. With this caveat, it is possible to identify pollination syndromes from large datasets and to reliably extrapolate them for taxa for which direct observations are unavailable. PMID:29036172

  18. Apple Pollination: Demand Depends on Variety and Supply Depends on Pollinator Identity.

    Science.gov (United States)

    Garratt, M P D; Breeze, T D; Boreux, V; Fountain, M T; McKerchar, M; Webber, S M; Coston, D J; Jenner, N; Dean, R; Westbury, D B; Biesmeijer, J C; Potts, S G

    2016-01-01

    Insect pollination underpins apple production but the extent to which different pollinator guilds supply this service, particularly across different apple varieties, is unknown. Such information is essential if appropriate orchard management practices are to be targeted and proportional to the potential benefits pollinator species may provide. Here we use a novel combination of pollinator effectiveness assays (floral visit effectiveness), orchard field surveys (flower visitation rate) and pollinator dependence manipulations (pollinator exclusion experiments) to quantify the supply of pollination services provided by four different pollinator guilds to the production of four commercial varieties of apple. We show that not all pollinators are equally effective at pollinating apples, with hoverflies being less effective than solitary bees and bumblebees, and the relative abundance of different pollinator guilds visiting apple flowers of different varieties varies significantly. Based on this, the taxa specific economic benefits to UK apple production have been established. The contribution of insect pollinators to the economic output in all varieties was estimated to be £92.1M across the UK, with contributions varying widely across taxa: solitary bees (£51.4M), honeybees (£21.4M), bumblebees (£18.6M) and hoverflies (£0.7M). This research highlights the differences in the economic benefits of four insect pollinator guilds to four major apple varieties in the UK. This information is essential to underpin appropriate investment in pollination services management and provides a model that can be used in other entomolophilous crops to improve our understanding of crop pollination ecology.

  19. Apple Pollination: Demand Depends on Variety and Supply Depends on Pollinator Identity.

    Directory of Open Access Journals (Sweden)

    M P D Garratt

    Full Text Available Insect pollination underpins apple production but the extent to which different pollinator guilds supply this service, particularly across different apple varieties, is unknown. Such information is essential if appropriate orchard management practices are to be targeted and proportional to the potential benefits pollinator species may provide. Here we use a novel combination of pollinator effectiveness assays (floral visit effectiveness, orchard field surveys (flower visitation rate and pollinator dependence manipulations (pollinator exclusion experiments to quantify the supply of pollination services provided by four different pollinator guilds to the production of four commercial varieties of apple. We show that not all pollinators are equally effective at pollinating apples, with hoverflies being less effective than solitary bees and bumblebees, and the relative abundance of different pollinator guilds visiting apple flowers of different varieties varies significantly. Based on this, the taxa specific economic benefits to UK apple production have been established. The contribution of insect pollinators to the economic output in all varieties was estimated to be £92.1M across the UK, with contributions varying widely across taxa: solitary bees (£51.4M, honeybees (£21.4M, bumblebees (£18.6M and hoverflies (£0.7M. This research highlights the differences in the economic benefits of four insect pollinator guilds to four major apple varieties in the UK. This information is essential to underpin appropriate investment in pollination services management and provides a model that can be used in other entomolophilous crops to improve our understanding of crop pollination ecology.

  20. Pollination ecology of two species of Elleanthus (Orchidaceae): novel mechanisms and underlying adaptations to hummingbird pollination.

    Science.gov (United States)

    Nunes, C E P; Amorim, F W; Mayer, J L S; Sazima, M

    2016-01-01

    Relationships among floral biology, floral micromorphology and pollinator behaviour in bird-pollinated orchids are important issues to understand the evolution of the huge flower diversity within Orchidaceae. We aimed to investigate floral mechanisms underlying the interaction with pollinators in two hummingbird-pollinated orchids occurring in the Atlantic forest. We assessed floral biology, nectar traits, nectary and column micromorphologies, breeding systems and pollinators. In both species, nectar is secreted by lip calli through spaces between the medial lamellar surfaces of epidermal cells. Such a form of floral nectar secretion has not been previously described. Both species present functional protandry and are self-compatible yet pollinator-dependent. Fruit set in hand-pollination experiments was more than twice that under natural conditions, evidencing pollen limitation. The absence of fruit set in interspecific crosses suggests the existence of post-pollination barriers between these sympatric co-flowering species. In Elleanthus brasiliensis, fruits resulting from cross-pollination and natural conditions were heavier than those resulting from self-pollination, suggesting advantages to cross-pollination. Hummingbirds pollinated both species, which share at least one pollinator species. Species differences in floral morphologies led to distinct pollination mechanisms. In E. brasiliensis, attachment of pollinarium to the hummingbird bill occurs through a lever apparatus formed by an appendage in the column, another novelty to our knowledge of orchid pollination. In E. crinipes, pollinarium attachment occurs by simple contact with the bill during insertion into the flower tube, which fits tightly around it. The novelties described here illustrate the overlooked richness in ecology and morphophysiology in Orchidaceae. © 2015 German Botanical Society and The Royal Botanical Society of the Netherlands.

  1. Pollination ecology and reproductive biology of Canarium strictum Roxb. from evergreen forests of Central Western Ghats, India.

    Science.gov (United States)

    Kumar, C N Prasanna; Somashekar, R K; Nagaraja, B C; Shivaprasad, D

    2015-09-01

    Pollination and reproductive biology of a dioecious tree Canarium strictum Roxb. (Burseraceae) was extensively studied within the Agumbe forest range of Western Ghats, Karnataka to identify primary pollen vectors and to enumerate interrelationship with the pollinators. The study also investigated phenology, floral biology, pollen production, pollen viability, stigma receptivity and nectar production. Trees produced functionally unisexual flowers with white petals, organized densely on inflorescences. Staminate flowers produced high percentage of viable pollen and relatively abundant nectar (15.75 μl) as a reward to the pollinators, while pistillate flowers produced only nectar (12 μl). Successful fruit set with wind pollination was facilitated by synchronization of flowering male and female trees, long term receptivity of stigma in female flowers and extended lifespan of flowers. The highest mean percent of fruit set with hand cross-pollination (μ = 91.06) suggests the influence of local male tree density, as well as, frequency and abundance of pollinator community on fruit set by open pollination.

  2. Do pollinator distributions underlie the evolution of pollination ecotypes in the Cape shrub Erica plukenetii?

    Science.gov (United States)

    Van der Niet, Timotheüs; Pirie, Michael D; Shuttleworth, Adam; Johnson, Steven D; Midgley, Jeremy J

    2014-01-01

    According to the Grant-Stebbins model of pollinator-driven divergence, plants that disperse beyond the range of their specialized pollinator may adapt to a new pollination system. Although this model provides a compelling explanation for pollination ecotype formation, few studies have directly tested its validity in nature. Here we investigate the distribution and pollination biology of several subspecies of the shrub Erica plukenetii from the Cape Floristic Region in South Africa. We analyse these data in a phylogenetic context and combine these results with information on pollinator ranges to test whether the evolution of pollination ecotypes is consistent with the Grant-Stebbins model. Pollinator observations showed that the most common form of E. plukenetii with intermediate corolla length is pollinated by short-billed Orange-breasted sunbirds. Populations at the northern fringe of the distribution are characterized by long corollas, and are mainly pollinated by long-billed Malachite sunbirds. A population with short corollas in the centre of the range was mainly pollinated by insects, particularly short-tongued noctuid moths. Bird exclusion in this population did not have an effect on fruit set, while insect exclusion reduced fruit set. An analysis of floral scent across the range, using coupled gas chromatography-mass spectrometry, showed that the scent bouquets of flowers from moth-pollinated populations are characterized by a larger number of scent compounds and higher emission rates than those in bird-pollinated populations. This was also reflected in clear separation of moth- and bird-pollinated populations in a two-dimensional phenotype space based on non-metric multidimensional scaling analysis of scent data. Phylogenetic analyses of chloroplast and nuclear DNA sequences strongly supported monophyly of E. plukenetii, but not of all the subspecies. Reconstruction of ancestral character states suggests two shifts from traits associated with short

  3. The Dependence of Crops for Pollinators and the Economic Value of Pollination in Brazil.

    Science.gov (United States)

    Giannini, T C; Cordeiro, G D; Freitas, B M; Saraiva, A M; Imperatriz-Fonseca, V L

    2015-06-01

    Food production is challenged by changes in climate and land use and expanding human population growth. Proper pollination can increase the production and quality of fruit, nut, oil, and fiber crops. We reviewed crop dependence on pollinators and estimated the economic value of pollination per year for each crop in Brazil. We analyzed 141 crops and found that 85 depend on pollinators. Almost one-third of these crops have an essential or great dependence on pollinators. The economic contribution of pollinators totals ∼30% (∼US$12 billion) of the total annual agricultural income of the dependent crops (totalizing almost US$45 billion). However, half of these figures includes soybean crop (US$5.7 billion of pollinators' contribution and US$22 billion of annual income). Soybean was considered as having a modest dependence on pollinators, but this remains controversial because pollinator dependence might vary among different varieties cultivated in Brazil. Moreover, we have no information about pollinator dependence regarding some important crops, showing the urgent need for basic research into reproductive biology and pollination ecology. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  4. The modularity of pollination networks

    DEFF Research Database (Denmark)

    Olesen, Jens Mogens; Bascompte, J.; Dupont, Yoko

    2007-01-01

    consist of strongly connected species. The importance of modularity has been discussed for a long time, but no consensus on its prevalence in ecological networks has yet been reached. Progress is hampered by inadequate methods and a lack of large datasets. We analyzed 51 pollination networks including...... linked species within their own module), connectors linking different modules, or both. If these key species go extinct, modules and networks may break apart and initiate cascades of extinction. Thus, species serving as hubs and connectors should receive high conservation priorities.    ...

  5. Self-pollination rate and floral-display size in Asclepias syriaca (Common Milkweed) with regard to floral-visitor taxa.

    Science.gov (United States)

    Howard, Aaron F; Barrows, Edward M

    2014-06-23

    Animals fertilize thousands of angiosperm species whose floral-display sizes can significantly influence pollinator behavior and plant reproductive success. Many studies have measured the interactions among pollinator behavior, floral-display size, and plant reproductive success, but few studies have been able to separate the effects of pollinator behavior and post-pollination processes on angiosperm sexual reproduction. In this study, we utilized the highly self-incompatible pollinium-pollination system of Asclepias syriaca (Common Milkweed) to quantify how insect visitors influenced male reproductive success measured as pollen removal, female reproductive success measured as pollen deposition, and self-pollination rate. We also determined how floral-display size impacts both visitor behavior and self-pollination rate. Four insect taxonomic orders visited A. syriaca: Coleoptera, Diptera, Hymenoptera, and Lepidoptera. We focused on three groups of visitor taxa within two orders (Hymenoptera and Lepidoptera) with sample sizes large enough for quantitative analysis: Apis mellifera (Western Honey Bee), Bombus spp. (bumble bees) and lepidopterans (butterflies and moths). Qualitatively, lepidopterans had the highest pollinator importance values, but the large variability in the lepidopteran data precluded meaningful interpretation of much of their behavior. The introduced A. mellifera was the most effective and most important diurnal pollinator with regard to both pollen removal and pollen deposition. However, when considering the self-incompatibility of A. syriaca, A. mellifera was not the most important pollinator because of its high self-pollination rate as compared to Bombus spp. Additionally, the rate of self-pollination increased more rapidly with the number of flowers per inflorescence in A. mellifera than in the native Bombus spp. Apis mellifera's high rate of self-pollination may have significant negative effects on both male and female reproductive successes

  6. Broad-spectrum pollination of Plectranthus neochilus

    Directory of Open Access Journals (Sweden)

    C. H. Stirton

    1977-11-01

    Full Text Available The pollination ecology of Plectranthus neochilus Schltr. is discussed and compared with that of another garden plant,  Plectranthus barbatus Andr.. Pollinators and flower visitors of P. neochilus include members of  the Megachilidae, Anthophoridae, Syrphidae, Bombyliidae, Sphingidae, Apidae.

  7. An evolutionary basis for pollination ecology

    NARCIS (Netherlands)

    Willemstein, S.C.

    1987-01-01

    In the introduction and chapter 2 the incentives and way of reasoning are given for the description of an evolutionary basis of pollination ecology. Starting from the until recently rather anecdotical character of the study of pollination ecology as a whole, and in the absence of large-scale

  8. Pollination Research Methods with Apis mellifera

    Science.gov (United States)

    This chapter describes field and lab procedures for doing experiments on honey bee pollination. Most of the methods apply to any insect for whom pollen vectoring capacity is the question. What makes honey bee pollination distinctive is its historic emphasis on agricultural applications; hence one fi...

  9. Seasonal and annual variations in the pollination efficiency of a pollinator community of Dictamnus albus L.

    Science.gov (United States)

    Fisogni, A; Rossi, M; Sgolastra, F; Bortolotti, L; Bogo, G; de Manincor, N; Quaranta, M; Galloni, M

    2016-05-01

    The interplay between insect and plant traits outlines the patterns of pollen transfer and the subsequent plant reproductive fitness. We studied the factors that affect the pollination efficiency of a pollinator community of Dictamnus albus L. by evaluating insect behaviour and morphological characteristics in relation to flowering phenology. In order to extrapolate the pollinator importance of single taxa and of the whole pollinator guild, we calculated an index distinguishing between potential (PPI) and realized (RPI) pollinator importance. Although the pollinator species spectrum appeared rather constant, we found high intra- and inter-annual variability of pollinator frequency and importance within the insect community. Flower visitation rate strictly depended on insect abundance and on the overlap between their flying period and flower blooming. All the pollinators visited flowers from the bottom to the top of the racemes, excluding intra-plant geitonogamous pollination, and most of them showed high pollen fidelity. Only medium large-sized bees could contact the upward bending stiles while feeding on nectar, highlighting a specialisation of the plant towards bigger pollinators. Moreover, we found evidence of functional specialisation, since all pollinators were restricted to a single taxonomic group (order: Hymenoptera; superfamily: Apoidea). Both the PPI and RPI indices indicate Habropoda tarsata as the most important pollinator of D. albus. Following hand cross-pollination experiments we revealed the presence of pollination limitation in 1 of the 3 years of field study. We discuss this result in relation to flowering abundance and to possible mismatches of phenological periods between plants and insects. © 2015 German Botanical Society and The Royal Botanical Society of the Netherlands.

  10. Pollination and mating systems of Apodanthaceae and the distribution of reproductive traits in parasitic angiosperms.

    Science.gov (United States)

    Bellot, Sidonie; Renner, Susanne S

    2013-06-01

    The most recent reviews of the reproductive biology and sexual systems of parasitic angiosperms were published 17 yr ago and reported that dioecy might be associated with parasitism. We use current knowledge on parasitic lineages and their sister groups, and data on the reproductive biology and sexual systems of Apodanthaceae, to readdress the question of possible trends in the reproductive biology of parasitic angiosperms. • Fieldwork in Zimbabwe and Iran produced data on the pollinators and sexual morph frequencies in two species of Apodanthaceae. Data on pollinators, dispersers, and sexual systems in parasites and their sister groups were compiled from the literature. • With the possible exception of some Viscaceae, most of the ca. 4500 parasitic angiosperms are animal-pollinated, and ca. 10% of parasites are dioecious, but the gain and loss of dioecy across angiosperms is too poorly known to infer a statistical correlation. The studied Apodanthaceae are dioecious and pollinated by nectar- or pollen-foraging Calliphoridae and other flies. • Sister group comparisons so far do not reveal any reproductive traits that evolved (or were lost) concomitant with a parasitic life style, but the lack of wind pollination suggests that this pollen vector may be maladaptive in parasites, perhaps because of host foliage or flowers borne close to the ground.

  11. Effect of nectar secretion rate on pollination success of Passiflora coccinea (Passifloraceae) in the Central Amazon.

    Science.gov (United States)

    Fischer, E; Leal, I R

    2006-05-01

    The pollination of Passiflora coccinea by the hummingbird Phaethornis superciliosus was studied in Central Amazon, Brazil. We hypothesized that a greater nectar secretion rate (NSR) increases the pollination success of single flowers through Ph. superciliosus visiting behavior. For control flowers, NSR was an increasing function of flower base diameter (FBD). The total number of Ph. superciliosus probes per flower was an increasing function of FBD. Additionally, deposition of pollen on stigmas increased with the cumulative number of Ph. superciliosus probes. Our results show that larger P. coccinea flowers secrete nectar at higher rates, are probed more times during each hummingbird visit and are more successful at pollination. This seems to be the first non-manipulative study describing such an effect of NSR on the pollination of single flowers in nature.

  12. Effect of nectar secretion rate on pollination success of Passiflora coccinea (Passifloraceae in the Central Amazon

    Directory of Open Access Journals (Sweden)

    E. Fischer

    Full Text Available The pollination of Passiflora coccinea by the hummingbird Phaethornis superciliosus was studied in Central Amazon, Brazil. We hypothesized that a greater nectar secretion rate (NSR increases the pollination success of single flowers through Ph. superciliosus visiting behavior. For control flowers, NSR was an increasing function of flower base diameter (FBD. The total number of Ph. superciliosus probes per flower was an increasing function of FBD. Additionally, deposition of pollen on stigmas increased with the cumulative number of Ph. superciliosus probes. Our results show that larger P. coccinea flowers secrete nectar at higher rates, are probed more times during each hummingbird visit and are more successful at pollination. This seems to be the first non-manipulative study describing such an effect of NSR on the pollination of single flowers in nature.

  13. Irrigation method does not affect wild bee pollinators of hybrid sunflower

    Directory of Open Access Journals (Sweden)

    Hillary Sardiñas

    2016-09-01

    Full Text Available Irrigation method has the potential to directly or indirectly influence populations of wild bee crop pollinators nesting and foraging in irrigated crop fields. The majority of wild bee species nest in the ground, and their nests may be susceptible to flooding. In addition, their pollination of crops can be influenced by nectar quality and quantity, which are related to water availability. To determine whether different irrigation methods affect crop pollinators, we compared the number of ground-nesting bees nesting and foraging in drip- and furrow-irrigated hybrid sunflower fields in the Sacramento Valley. We found that irrigation method did not impact wild bee nesting rates or foraging bee abundance or bee species richness. These findings suggest that changing from furrow irrigation to drip irrigation to conserve water likely will not alter hybrid sunflower crop pollination.

  14. Reproductive biology and pollination ecology of Triplaris gardneriana (Polygonaceae): a case of ambophily in the Brazilian Chaco.

    Science.gov (United States)

    Custodio, T; Comtois, P; Araujo, A C

    2017-07-01

    Triplaris gardneriana (Polygonaceae) is a dioecious pioneer tree reported as insect-pollinated, despite possessing traits related to anemophily. Here, we analyse the possible roles of insects and wind on the pollination of this species to establish whether the species is ambophilous. We carried out observations of floral biology, as well as on the frequency and behaviour of pollinators visiting flowers in a population of T. gardneriana in the Chaco vegetation of Brazil. We conducted experimental pollinations to determine the maternal fertility of female plants and whether they were pollen-limited, and we also conducted aerobiological experiments to provide evidence of how environmental factors influence atmospheric pollen dispersal. The population comprised an area of approximately 152.000 m 2 and was composed of 603 female and 426 male plants (sex ratio = 0.59:0.41). We observed 48 species of insects visiting flowers of T. gardneriana, of which the bees Scaptotrigona depilis and Apis mellifera scutellata were the most effective pollinators. We recorded pollen grains dispersed by wind on 74% of the glass slides placed on females, located at different distances (1-10 m) from male plants. Airborne pollen concentration was negatively correlated with relative humidity and positively correlated with temperature. Our observations and experimental results provide the first evidence that T. gardneriana is an ambophilous species, with pollen dispersal resulting from both animal and wind pollination. This mixed pollination strategy may be adaptive in T. gardneriana providing reproductive assurance during colonisation of sites with different biotic and abiotic conditions. © 2017 German Botanical Society and The Royal Botanical Society of the Netherlands.

  15. Floral neighborhood influences pollinator assemblages and effective pollination in a native plant.

    Science.gov (United States)

    Bruckman, Daniela; Campbell, Diane R

    2014-10-01

    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.

  16. A horizon scan of future threats and opportunities for pollinators and pollination

    Directory of Open Access Journals (Sweden)

    Mark J.F. Brown

    2016-08-01

    Full Text Available Background. Pollinators, which provide the agriculturally and ecologically essential service of pollination, are under threat at a global scale. Habitat loss and homogenisation, pesticides, parasites and pathogens, invasive species, and climate change have been identified as past and current threats to pollinators. Actions to mitigate these threats, e.g., agri-environment schemes and pesticide-use moratoriums, exist, but have largely been applied post-hoc. However, future sustainability of pollinators and the service they provide requires anticipation of potential threats and opportunities before they occur, enabling timely implementation of policy and practice to prevent, rather than mitigate, further pollinator declines. Methods.Using a horizon scanning approach we identified issues that are likely to impact pollinators, either positively or negatively, over the coming three decades. Results.Our analysis highlights six high priority, and nine secondary issues. High priorities are: (1 corporate control of global agriculture, (2 novel systemic pesticides, (3 novel RNA viruses, (4 the development of new managed pollinators, (5 more frequent heatwaves and drought under climate change, and (6 the potential positive impact of reduced chemical use on pollinators in non-agricultural settings. Discussion. While current pollinator management approaches are largely driven by mitigating past impacts, we present opportunities for pre-emptive practice, legislation, and policy to sustainably manage pollinators for future generations.

  17. Pollination and seed dispersal in the endangered succulent ...

    African Journals Online (AJOL)

    Euphorbia brevitorta relies on pollinators for fruit-set as it bears separate male and female flowers on the same plant, but appears to be self-compatible. Euphorbia brevitorta was found to have a generalist pollination system, with insects being the main pollinators. Pollinators of E. brevitorta comprise a wide range of insects ...

  18. Effects of honeybee ( Apis mellifera ) pollination on seed set in ...

    African Journals Online (AJOL)

    This study was carried out to determine the efficiency of pollination with honeybee (Apis mellifera) on sunflower hybrid seed production under different types of pollination during 2005 and 2006 in Mustafakemalpasa-Bursa, Turkey. Three pollination types (1) in cages with honeybees, (2) hand pollination (in cages) and (3) in ...

  19. The Ongoing Addition of Infrasound Sensors and the Flexette Wind-Noise Reducing System to Global Seismic Network Stations Operated by Project IDA

    Science.gov (United States)

    Ebeling, C. W.; Coon, C.

    2017-12-01

    Infrasound sensors are now being installed at Global Seismic Network (GSN) stations meeting certain infrastructure criteria. Manufactured by Hyperion Technology Group, Inc., these instruments (model IFS-3312) have a nominal sensitivity of 140 mV/Pa (at 1 Hz), a full-scale range of ±100 Pa, and a dynamic range of 120 dB. Low power consumption (750 mW at 12 VDC) and small size (153 mm x 178 mm) ease incorporation into the mix of existing GSN instrumentation. The accompanying flexible rosette ("Flexette") acoustic wind-noise reducing system, designed by Project IDA (International Deployment of Accelerometers-IDA), optimally includes 24 inlets, 4 secondary manifolds, and a single primary manifold. Each secondary manifold is connected to 6 inlets and to the primary manifold by 10-ft air hoses, thus eliminating stresses and the greater potential for leaks associated with the use of pipe. While the main design goal was to maximize the reduction of acoustic wind-noise over the widest range of wind speeds possible, consideration of additional criteria resulted in a Flexette base design easily tailored to meet individual station constraints and restrictions, made up of inexpensive (total cost Management Center (IRIS-DMC).

  20. Modularity, pollination systems, and interaction turnover in plant-pollinator networks across space.

    Science.gov (United States)

    Carstensen, Daniel W; Sabatino, Malena; Morellato, Leonor Patricia C

    2016-05-01

    Mutualistic interaction networks have been shown to be structurally conserved over space and time while pairwise interactions show high variability. In such networks, modularity is the division of species into compartments, or modules, where species within modules share more interactions with each other than they do with species from other modules. Such a modular structure is common in mutualistic networks and several evolutionary and ecological mechanisms have been proposed as underlying drivers. One prominent explanation is the existence of pollination syndromes where flowers tend to attract certain pollinators as determined by a set of traits. We investigate the modularity of seven community level plant-pollinator networks sampled in rupestrian grasslands, or campos rupestres, in SE Brazil. Defining pollination systems as corresponding groups of flower syndromes and pollinator functional groups, we test the two hypotheses that (1) interacting species from the same pollination system are more often assigned to the same module than interacting species from different pollination systems and; that (2) interactions between species from the same pollination system are more consistent across space than interactions between species from different pollination systems. Specifically we ask (1) whether networks are consistently modular across space; (2) whether interactions among species of the same pollination system occur more often inside modules, compared to interactions among species of different pollination systems, and finally; (3) whether the spatial variation in interaction identity, i.e., spatial interaction rewiring, is affected by trait complementarity among species as indicated by pollination systems. We confirm that networks are consistently modular across space and that interactions within pollination systems principally occur inside modules. Despite a strong tendency, we did not find a significant effect of pollination systems on the spatial consistency of

  1. A comparative analysis of pollinator type and pollen ornamentation in the Araceae and the Arecaceae, two unrelated families of the monocots

    Directory of Open Access Journals (Sweden)

    Anstett Marie-Charlotte

    2009-07-01

    Full Text Available Abstract Background The high diversity of ornamentation type in pollen grains of angiosperms has often been suggested to be linked to diversity in pollination systems. It is commonly stated that smooth pollen grains are associated with wind or water pollination while sculptured pollen grains are associated with biotic pollination. We tested the statistical significance of an association between pollen ornamentation and pollination system in two families of the monocotyledons, the Araceae and the Arecaceae, taking into account the phylogenetic framework. Findings Character optimization was carried out with the Maximum Parsimony method and two different methods of comparative analysis were used: the Concentrated-Change test and the Discrete method. The ancestral ornamentation in Araceae is foveolate/reticulate. It is probably the same in Arecaceae. The ancestral flowers of Araceae were pollinated by beetles while ancestral pollination in Arecaceae is equivocal. A correlation between ornamentation type and pollination was highlighted in Araceae although the results slightly differ depending on the method and the options chosen for performing the analyses. No correlation was found in palms. Conclusion In this study, we show that the relationships between the ornamentation type and the pollination system depend on the family and hence vary among taxonomic groups. We also show that the method chosen may strongly influence the results.

  2. Hybrid floral scent novelty drives pollinator shift in sexually deceptive orchids

    Directory of Open Access Journals (Sweden)

    Cozzolino Salvatore

    2010-04-01

    Full Text Available Abstract Background Sexually deceptive orchids of the genus Ophrys attract their pollinators, male insects, on a highly specific basis through the emission of odour blends that mimic the female sex pheromone of the targeted species. In this study, we have investigated a contact site between Ophrys arachnitiformis and O. lupercalis, two sympatric orchid species that are usually reproductively isolated via the exploitation of different pollinator "niches", but occasionally hybridise despite their apparent combination of ethological and mechanical isolation barriers. In particular, we have investigated the extent to which these Ophrys hybrids generate "emergent" combinations (i.e. novel and unpredictable from the parents' phenotypes of floral traits, and how these phenotypic novelties, particularly the odour blends emitted by the flower, could facilitate the invasion of a novel pollinator "niche" and induce the rapid formation of reproductive isolation, a prerequisite for adaptive evolutionary divergence. Results Our chemical analyses of floral scents show that the Ophrys F1 hybrids investigated here produce more compounds, significantly different ratios (% of odour compounds in the total blend, as well as new compounds in their floral odour compared to their progenitors. When tested for their attractiveness to the pollinator of each parent orchid species, we found that floral scent extracts of the hybrids triggered less inspecting flights and contacts by the male bees with the scented dummy than those of the parental orchid species. However, a series of additional behavioural bioassays revealed that the novel floral scent of the hybrids was significantly more attractive than either of the two parents to a pollinator species not initially involved in the pollination of any of the parent Ophrys species. Conclusions Collectively, our results illustrate that the process of hybridisation can lead to the generation of evolutionary novelties, and that

  3. Economic Evaluation of Pollination Services Comparing Coffee Landscapes in Ecuador and Indonesia

    Directory of Open Access Journals (Sweden)

    Roland Olschewski

    2006-06-01

    Full Text Available Biodiversity conservation through land-use systems on private land is becoming a pressing environmental policy issue. Agroforestry, such as shade-coffee production, contributes to biodiversity conservation. However, falling coffee prices force many coffee growers to convert their sites into economically more attractive land uses. We performed an economic evaluation of coffee pollination by bees in two distinct tropical regions: an area of low human impact with forests neighboring agroforestry in Indonesia and an area of high human impact with little remaining forest in Ecuador. We evaluated bee pollination for different forest-destruction scenarios, where coffee yields depend on forests to provide nesting sites for bees. We used two novel approaches. First, we examined how coffee net revenues depend on the pollination services of adjacent forests by considering berry weight in addition to fruit set, thereby providing a comprehensive evaluation. Second, we determined the net welfare effects of land-use changes, including the fact that former forestland is normally used for alternative crops. In both regions, crop revenues exceeded coffee pollination values, generating incentives to convert forests, even if owners would be compensated for pollination services. The promotion of certified "biodiversity-friendly" coffee is a feasible option to maintain shade-coffee systems. This is of special importance in high-impact areas where only small forest fragments remain. We conclude that a comprehensive economic analysis is necessary to adequately evaluate rainforest preservation for the enhancement of ecosystem services, such as pollination.

  4. Generalist versus specialist pollination systems in 26 Oenothera (Onagraceae

    Directory of Open Access Journals (Sweden)

    Kyra Neipp Krakos

    2014-09-01

    Full Text Available Although generalized and specialized plants are often discussed as alternative states, the biological reality may better be viewed as a continuum. However, estimations of pollinator specificity have been confounded in some studies by the assumption that all floral visitors are pollinators. Failure to account for pollen load can lead to inaccurate conclusions regarding the number of pollinators with which a species actually interacts. The aim of this study was to clarify the distribution of pollination-system specialization within one clade, using a more rigorous assessment of pollen flow. The genus Oenothera has long been used as a model system for studying reproductive biology, and it provides a diversity of pollination systems and a wealth of historical data. Both floral visitation rate and pollen-load analysis of sampled pollinators, combined into a metric of pollen flow, were used to quantify the pollination systems of 26 Oenothera taxa. Metric of pollinator specialization were calculated as functions of both total pollinator taxa, and as pollinator functional groups. We found that for Oenothera, the number of floral visitors highly overestimates the number of pollinators, and is inadequate for determining or predicting pollination system specialization. We found that that pollination systems were distributed on a gradient from generalized to specialized, with more pollinator-specialized plant taxa, especially when estimated using pollinator functional groups. These results are in conflict with previous studies that depict most plant species as generalists, and this finding may be related to how prior studies have estimated specialization.

  5. Plasticity of floral longevity and floral display in the self-compatible biennial Sabatia angularis (Gentianaceae): untangling the role of multiple components of pollination.

    Science.gov (United States)

    Spigler, Rachel B

    2017-01-01

    Plasticity of floral traits in response to pollination can enable plants to maximize opportunities for pollen import and export under poor pollination conditions, while minimizing costs under favourable ones. Both floral longevity and display are key traits influencing pollination. While pollination-induced flower wilting is widely documented, we lack an understanding of the multifactorial complexity of this response, including the influence of other pollination components, costs of extended longevity and subsequent impacts on floral display. Plasticity of floral longevity was experimentally evaluated in Sabatia angularis in response to multiple pollination factors: pollen addition, removal, and source (self, single-donor outcross, multiple-donor outcross) and timing of pollination. Effects of pollen quantity were further evaluated by exploiting variation in autonomous self-pollen deposition. Delayed pollination costs were tested comparing seed set from early versus late pollinations. Finally, I compared floral display metrics (peak floral display, time to peak flower, flowering duration, mean flowering rate) between experimentally pollinated and control plants. Floral longevity was highly plastic in response to pollen addition and its timing, and the response was dose-dependent but insensitive to pollen source. Pollen removal tended to extend floral longevity, but only insofar as it precluded pollination-induced wilting via autonomous self-pollination. Under delayed pollination, the wilting response was faster and no cost was detected. Pollination further led to reduced peak floral displays and condensed flowering periods. Floral longevity and display plasticity could optimize fitness in S. angularis, a species prone to pollen limitation and high inbreeding depression. Under pollinator scarcity, extended floral longevities offer greater opportunities for pollen receipt and export at no cost to seed set, reproductive assurance via autonomous self-pollination and

  6. Learning in Insect Pollinators and Herbivores.

    Science.gov (United States)

    Jones, Patricia L; Agrawal, Anurag A

    2017-01-31

    The relationship between plants and insects is influenced by insects' behavioral decisions during foraging and oviposition. In mutualistic pollinators and antagonistic herbivores, past experience (learning) affects such decisions, which ultimately can impact plant fitness. The higher levels of dietary generalism in pollinators than in herbivores may be an explanation for the differences in learning seen between these two groups. Generalist pollinators experience a high level of environmental variation, which we suggest favors associative learning. Larval herbivores employ habituation and sensitization-strategies useful in their less variable environments. Exceptions to these patterns based on habitats, mobility, and life history provide critical tests of current theory. Relevant plant traits should be under selection to be easily learned and remembered in pollinators and difficult to learn in herbivores. Insect learning thereby has the potential to have an important, yet largely unexplored, role in plant-insect coevolution.

  7. Pollinator attraction of the wasp-flower Scrophularia umbrosa (Scrophulariaceae).

    Science.gov (United States)

    Brodmann, J; Emer, D; Ayasse, M

    2012-05-01

    Certain species of Scrophularia (Scrophulariaceae), such as S. nodosa and S. umbrosa, are mainly pollinated by social wasps and are consequently described as wasp-flowers. Because plants attract their pollinators with the help of various floral cues, such as floral odour and/or optical cues, we have investigated the role of olfactory and visual floral signals responsible for wasp attraction in S. umbrosa. Using a combination of chemical (GC, GC-MS) and electrophysiological analyses (GC-EAD), we identified ten compounds in the complex floral odour bouquet that are detectable by the wasps' antennae. As in the wasp-flower Epipactis helleborine, we found so-called 'green leaf volatiles' (GLVs) in the floral odour; these GLVs are highly attractive to the wasps. GLVs, mostly six-carbon aldehydes, alcohols and acetates, and other volatile organic compounds (VOCs), are emitted by many plants infested with herbivores, e.g. caterpillars. In contrast to other investigated wasp-flowers, behavioural experiments have demonstrated that, in addition to the floral odour of S. umbrosa, visual cues are involved in pollinator attraction. © 2011 German Botanical Society and The Royal Botanical Society of the Netherlands.

  8. Metabolic Control of Tobacco Pollination by Sugars and Invertases1

    Science.gov (United States)

    Goetz, Marc; Hirsche, Jörg; Bauerfeind, Martin Andreas; González, María-Cruz; Hyun, Tae Kyung; Eom, Seung Hee; Chriqui, Dominique; Engelke, Thomas; Großkinsky, Dominik K.; Roitsch, Thomas

    2017-01-01

    Pollination in flowering plants is initiated by germination of pollen grains on stigmas followed by fast growth of pollen tubes representing highly energy-consuming processes. The symplastic isolation of pollen grains and tubes requires import of Suc available in the apoplast. We show that the functional coupling of Suc cleavage by invertases and uptake of the released hexoses by monosaccharide transporters are critical for pollination in tobacco (Nicotiana tabacum). Transcript profiling, in situ hybridization, and immunolocalization of extracellular invertases and two monosaccharide transporters in vitro and in vivo support the functional coupling in supplying carbohydrates for pollen germination and tube growth evidenced by spatiotemporally coordinated expression. Detection of vacuolar invertases in maternal tissues by these approaches revealed metabolic cross talk between male and female tissues and supported the requirement for carbohydrate supply in transmitting tissue during pollination. Tissue-specific expression of an invertase inhibitor and addition of the chemical invertase inhibitor miglitol strongly reduced extracellular invertase activity and impaired pollen germination. Measurements of (competitive) uptake of labeled sugars identified two import pathways for exogenously available Suc into the germinating pollen operating in parallel: direct Suc uptake and via the hexoses after cleavage by extracellular invertase. Reduction of extracellular invertase activity in pollen decreases Suc uptake and severely compromises pollen germination. We further demonstrate that Glc as sole carbon source is sufficient for pollen germination, whereas Suc is supporting tube growth, revealing an important regulatory role of both the invertase substrate and products contributing to a potential metabolic and signaling-based multilayer regulation of pollination by carbohydrates. PMID:27923989

  9. Metabolic Control of Tobacco Pollination by Sugars and Invertases.

    Science.gov (United States)

    Goetz, Marc; Guivarćh, Anne; Hirsche, Jörg; Bauerfeind, Martin Andreas; González, María-Cruz; Hyun, Tae Kyung; Eom, Seung Hee; Chriqui, Dominique; Engelke, Thomas; Großkinsky, Dominik K; Roitsch, Thomas

    2017-02-01

    Pollination in flowering plants is initiated by germination of pollen grains on stigmas followed by fast growth of pollen tubes representing highly energy-consuming processes. The symplastic isolation of pollen grains and tubes requires import of Suc available in the apoplast. We show that the functional coupling of Suc cleavage by invertases and uptake of the released hexoses by monosaccharide transporters are critical for pollination in tobacco (Nicotiana tabacum). Transcript profiling, in situ hybridization, and immunolocalization of extracellular invertases and two monosaccharide transporters in vitro and in vivo support the functional coupling in supplying carbohydrates for pollen germination and tube growth evidenced by spatiotemporally coordinated expression. Detection of vacuolar invertases in maternal tissues by these approaches revealed metabolic cross talk between male and female tissues and supported the requirement for carbohydrate supply in transmitting tissue during pollination. Tissue-specific expression of an invertase inhibitor and addition of the chemical invertase inhibitor miglitol strongly reduced extracellular invertase activity and impaired pollen germination. Measurements of (competitive) uptake of labeled sugars identified two import pathways for exogenously available Suc into the germinating pollen operating in parallel: direct Suc uptake and via the hexoses after cleavage by extracellular invertase. Reduction of extracellular invertase activity in pollen decreases Suc uptake and severely compromises pollen germination. We further demonstrate that Glc as sole carbon source is sufficient for pollen germination, whereas Suc is supporting tube growth, revealing an important regulatory role of both the invertase substrate and products contributing to a potential metabolic and signaling-based multilayer regulation of pollination by carbohydrates. © 2017 American Society of Plant Biologists. All Rights Reserved.

  10. Inbreeding in Mimulus guttatus reduces visitation by bumble bee pollinators.

    Directory of Open Access Journals (Sweden)

    David E Carr

    Full Text Available Inbreeding in plants typically reduces individual fitness but may also alter ecological interactions. This study examined the effect of inbreeding in the mixed-mating annual Mimulus guttatus on visitation by pollinators (Bombus impatiens in greenhouse experiments. Previous studies of M. guttatus have shown that inbreeding reduced corolla size, flower number, and pollen quantity and quality. Using controlled crosses, we produced inbred and outbred families from three different M. guttatus populations. We recorded the plant genotypes that bees visited and the number of flowers probed per visit. In our first experiment, bees were 31% more likely to visit outbred plants than those selfed for one generation and 43% more likely to visit outbred plants than those selfed for two generations. Inbreeding had only a small effect on the number of flowers probed once bees arrived at a genotype. These differences were explained partially by differences in mean floral display and mean flower size, but even when these variables were controlled statistically, the effect of inbreeding remained large and significant. In a second experiment we quantified pollen viability from inbred and self plants. Bees were 37-54% more likely to visit outbred plants, depending on the population, even when controlling for floral display size. Pollen viability proved to be as important as floral display in predicting pollinator visitation in one population, but the overall explanatory power of a multiple regression model was weak. Our data suggested that bees use cues in addition to display size, flower size, and pollen reward quality in their discrimination of inbred plants. Discrimination against inbred plants could have effects on plant fitness and thereby reinforce selection for outcrossing. Inbreeding in plant populations could also reduce resource quality for pollinators, potentially resulting in negative effects on pollinator populations.

  11. Reproductive biology and pollination of the carnivorous Genlisea violacea (Lentibulariaceae).

    Science.gov (United States)

    Aranguren, Y; Płachno, B J; Stpiczyńska, M; Miranda, V F O

    2018-05-01

    Genlisea violacea is a Brazilian endemic carnivorous plant species distributed in the cerrado biome, mainly in humid environments, on sandy and oligotrophic soil or wet rocks. Studies on reproductive biology or pollination in the Lentibulariaceae are notably scarce; regarding the genus Genlisea, the current study is the first to show systematic and standardised research on reproductive biology from field studies to describe the foraging of visiting insects and determine the effective pollinators of Genlisea. We studied two populations of G. violacea through the observation of flower visitors for 4 months of the rainy and dry seasons. Stigmatic receptivity, pollen viability, and breeding system were evaluated together with histochemistry and morphological analyses of flowers. The flowers showed stigmatic receptivity of 100% in open buds and mature flowers, reducing to 80% for senescent flowers. Nearly 80% of pollen grains are viable, decreasing to 40-45% after 48 h. Nectar is produced by glandular trichomes inside the spur. Two bee species are effective pollinators: one of the genus Lasioglossum (subgenus Dialictus: Halictidae) and the other of the genus Ceratina (subgenus Ceratinula: family Apidae). Moreover, bee-like flies of the Syrphidae family may also be additional pollinators. Genlisea violacea is an allogamous and self-compatible species. The differences in flower-visiting fauna for both populations can be attributed to factors such as climate, anthropogenic effect, seasonal factors related to insects and plants, as well as the morphological variation of flowers in both populations. © 2017 German Society for Plant Sciences and The Royal Botanical Society of the Netherlands.

  12. Petal micromorphology and its relationship to pollination.

    Science.gov (United States)

    Costa, V B S; Pimentel, R M M; Chagas, M G S; Alves, G D; Castro, C C

    2017-03-01

    The characteristics of petal epidermal conical cells affect the quality of the signals perceived by various pollinators. This study aimed to identify variations in micromorphological characteristics of flower petals and their relationship to melittophily, ornithophily and chiropterophily pollination systems. The petals of 11 species were analysed using scanning electron microscopy and optical microscopy and the micromorphological traits were described, measured and compared using Tukey's test, PCA and cluster analysis. Unlike chiropterophily, all melittophilous and some ornithophilous species possessed adaxial epidermal conical cells. Cluster grouping separated chiropterophilous flowers from melittophilous and ornithophilous. PCA analysis showed that the two morphometric profile of conical cells was the attribute that most strongly influenced the grouping of species. When considering the data set of the three pollination systems, melittophilous and ornithophilous plants were more similar to each other than they were to chriopterophilous species. The distance between conical cell apices is an important parameter in interactions with pollinators. This study facilitated recognition of smoothing pollinator resource access through petal micromorphological characteristics. Further research regarding the biometry of micromorphological traits related to pollination is required. © 2016 German Botanical Society and The Royal Botanical Society of the Netherlands.

  13. The influence of floral symmetry, dependence on pollinators and pollination generalization on flower size variation.

    Science.gov (United States)

    Lázaro, A; Totland, O

    2014-07-01

    The pollinator-mediated stabilizing selection hypothesis suggests that the specialized pollination system of zygomorphic flowers might cause stabilizing selection, reducing their flower size variation compared with actinomorphic flowers. However, the degree of ecological generalization and of dependence on pollinators varies greatly among species of both flower symmetry types and this may also affect flower size variation. Data on 43 species from two contrasting communities (one alpine and one lowland community) were used to test the relationships and interactions between flower size phenotypic variation, floral symmetry, ecological pollination generalization and species' dependence on pollinators. Contrary to what was expected, higher flower size variation was found in zygomorphic than in actinomorphic species in the lowland community, and no difference in flower size variation was found between symmetry types in the alpine community. The relationship between floral symmetry and flower size variation depended on ecological generalization and species' dependence on pollinators, although the influence of ecological generalization was only detected in the alpine community. Zygomorphic species that were highly dependent on pollinators and that were ecologically specialized were less variable in flower size than ecologically generalist and selfing zygomorphic species, supporting the pollinator-mediated stabilizing selection hypothesis. However, these relationships were not found in actinomorphic species, probably because they are not dependent on any particular pollinator for efficient pollination and therefore their flower size always shows moderate levels of variation. The study suggests that the relationship between flower size variation and floral symmetry may be influenced by population-dependent factors, such as ecological generalization and species' dependence on pollinators. © The Author 2014. Published by Oxford University Press on behalf of the Annals of

  14. Breaking-bud pollination: a new pollination process in partially opened flowers by small bees.

    Science.gov (United States)

    Yamaji, Futa; Ohsawa, Takeshi A

    2015-09-01

    Plant-pollinator interactions have usually been researched in flowers that have fully opened. However, some pollinators can visit flowers before full opening and contribute to fruit and seed sets. In this paper, we researched the pollination biology of flowers just starting to open in four field experiments. We observed the insect visitors to Lycoris sanguinea var. sanguinea for 3 years at five sites. These observations revealed that only small bees, Lasioglossum japonicum, often entered through tiny spaces between the tepals of 'breaking buds' (i.e. partially opened flowers) and collected pollen. We hypothesized that they can pollinate this species at the breaking-bud stage, when the stigma is located near the anthers. To measure the pollination effect of small bees at the breaking-bud stage, we bagged several breaking buds after small bees had visited them and examined whether these buds were pollinated. In bagging experiments, 30% of the breaking buds set fruit and seeds. Fruit-set ratios of the breaking buds did not differ significantly from those of the fully opened flowers, which had been visited by several insect species. We also counted the pollen grain numbers on the body of L. japonicum and on the anthers of randomly-selected and manipulated flowers. These experiments revealed that all of the captured bees had some pollen of target plants and that L. japonicum collected most of the pollen grains at the breaking-bud stage. Our results showed that the new pollination process, breaking-bud pollination, happened in breaking buds by L. japonicum, although there is no evidence to reveal that this is the most effective pollination method for L. sanguinea var. sanguinea. In principle, this new pollination process can occur in other flowering plants and our results are a major contribution to studies of plant-pollinator interactions.

  15. Evolutionary relationships among pollinators and repeated pollinator sharing in sexually deceptive orchids.

    Science.gov (United States)

    Phillips, R D; Brown, G R; Dixon, K W; Hayes, C; Linde, C C; Peakall, R

    2017-09-01

    The mechanism of pollinator attraction is predicted to strongly influence both plant diversification and the extent of pollinator sharing between species. Sexually deceptive orchids rely on mimicry of species-specific sex pheromones to attract their insect pollinators. Given that sex pheromones tend to be conserved among related species, we predicted that in sexually deceptive orchids, (i) pollinator sharing is rare, (ii) closely related orchids use closely related pollinators and (iii) there is strong bias in the wasp lineages exploited by orchids. We focused on species that are pollinated by sexual deception of thynnine wasps in the distantly related genera Caladenia and Drakaea, including new field observations for 45 species of Caladenia. Specialization was extreme with most orchids using a single pollinator species. Unexpectedly, seven cases of pollinator sharing were found, including two between Caladenia and Drakaea, which exhibit strikingly different floral morphology. Phylogenetic analysis of pollinators using four nuclear sequence loci demonstrated that although orchids within major clades primarily use closely related pollinator species, up to 17% of orchids within these clades are pollinated by a member of a phylogenetically distant wasp genus. Further, compared to the total diversity of thynnine wasps within the study region, orchids show a strong bias towards exploiting certain genera. Although these patterns may arise through conservatism in the chemical classes used in sex pheromones, apparent switches between wasp clades suggest unexpected flexibility in floral semiochemical production. Alternatively, wasp sex pheromones within lineages may exhibit greater chemical diversity than currently appreciated. © 2017 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2017 European Society For Evolutionary Biology.

  16. Generalization versus specialization in pollination systems: visitors, thieves, and pollinators of Hypoestes aristata (Acanthaceae.

    Directory of Open Access Journals (Sweden)

    Eliška Padyšáková

    Full Text Available Many recent studies have suggested that the majority of animal-pollinated plants have a higher diversity of pollinators than that expected according to their pollination syndrome. This broad generalization, often based on pollination web data, has been challenged by the fact that some floral visitors recorded in pollination webs are ineffective pollinators. To contribute to this debate, and to obtain a contrast between visitors and pollinators, we studied insect and bird visitors to virgin flowers of Hypoestes aristata in the Bamenda Highlands, Cameroon. We observed the flowers and their visitors for 2-h periods and measured the seed production as a metric of reproductive success. We determined the effects of individual visitors using 2 statistical models, single-visit data that were gathered for more frequent visitor species, and frequency data. This approach enabled us to determine the positive as well as neutral or negative impact of visitors on H. aristata's reproductive success. We found that (i this plant is not generalized but rather specialized; although we recorded 15 morphotaxa of visitors, only 3 large bee species seemed to be important pollinators; (ii the carpenter bee Xylocopa cf. inconstans was both the most frequent and the most effective pollinator; (iii the honey bee Apis mellifera acted as a nectar thief with apparent negative effects on the plant reproduction; and (iv the close relationship between H. aristata and carpenter bees was in agreement with the large-bee pollination syndrome of this plant. Our results highlight the need for studies detecting the roles of individual visitors. We showed that such an approach is necessary to evaluate the pollination syndrome hypothesis and create relevant evolutionary and ecological hypotheses.

  17. A heterogeneous landscape does not guarantee high crop pollination.

    Science.gov (United States)

    Samnegård, Ulrika; Hambäck, Peter A; Lemessa, Debissa; Nemomissa, Sileshi; Hylander, Kristoffer

    2016-09-14

    The expansion of pollinator-dependent crops, especially in the developing world, together with reports of worldwide pollinator declines, raises concern of possible yield gaps. Farmers directly reliant on pollination services for food supply often live in regions where our knowledge of pollination services is poor. In a manipulative experiment replicated at 23 sites across an Ethiopian agricultural landscape, we found poor pollination services and severe pollen limitation in a common oil crop. With supplementary pollination, the yield increased on average by 91%. Despite the heterogeneous agricultural matrix, we found a low bee abundance, which may explain poor pollination services. The variation in pollen limitation was unrelated to surrounding forest cover, local bee richness and bee abundance. While practices that commonly increase pollinators (restricted pesticide use, flower strips) are an integral part of the landscape, these elements are apparently insufficient. Management to increase pollination services is therefore in need of urgent investigation. © 2016 The Authors.

  18. Variation in pollinator effectiveness in swamp milkweed, Asclepias incarnata (Apocynaceae).

    Science.gov (United States)

    Ivey, Christopher T; Martinez, Pocholo; Wyatt, Robert

    2003-02-01

    The contribution of a pollinator toward plant fitness (i.e., its "effectiveness") can determine its importance for the plant's evolutionary ecology. We compared pollinators in a population of Asclepias incarnata (Apocynaceae) for several components of pollinator effectiveness over two flowering seasons to evaluate their importance to plant reproduction. Insects of the order Hymenoptera predominate in A. incarnata pollination, but there appears to be no specialization for pollination within this order. Pollinators varied significantly in nearly every component of effectiveness that we measured, including pollen load, removal and deposition of pollen, pollination efficiency (deposition/removal), flower-handling time, and potential for geitonogamy (fractional pollen deposition). The visitation rate of pollinators also varied significantly between years and through time within years. Pollination success and percentage fruit-set of unmanipulated plants in the population also varied significantly between years, and pollination success varied among sample times within years. Most components of effectiveness were weakly correlated, suggesting that the contributions of visitor species toward pollination varied among effectiveness components. Mean flower-handling time, however, was strongly correlated with several components, including pollen removal and deposition, pollination efficiency, and fractional pollen deposition. These findings highlight the significance of pollination variability for plant reproduction and suggest that time-dependent foraging behaviors may play an important role in determining pollinator effectiveness.

  19. Low-frequency noise from large wind turbines – additional data and assessment of new Danish regulations

    DEFF Research Database (Denmark)

    Pedersen, Christian Sejer; Møller, Henrik; Pedersen, Steffen

    2012-01-01

    turbines in Denmark. In this study, the data material has been increased to include more data on noise from modern production turbines up to 5 MW. In addition, the new Danish regulations are assessed. The previous result that the relative amount of low-frequency noise is higher for large turbines (> 2 MW...... frequencies, and for several of the investigated large turbines, the one-third-octave band with the highest level is at or below 250 Hz. It is thus beyond any doubt that the low-frequency part of the spectrum plays an important role in the noise at the neighbors. The new Danish regulation is based...

  20. Generalist bees pollinate red-flowered Penstemon eatonii: Duality in the hummingbird pollination syndrome

    Science.gov (United States)

    James H. Cane; Rick. Dunne

    2014-01-01

    The red tubular flowers of Penstemon eatonii (Plantaginaceae) typify the classic pollination syndrome for hummingbirds. Bees are thought to diminish its seed siring potential, but we found that foraging female generalist bees (Apis, Anthophora) deposited substantial amounts of conspecific pollen on P. eatonii stigmas. In the absence of hummingbirds, bee pollination of...

  1. Host pollination mode and mutualist pollinator presence: net effect of internally ovipositing parasite in the fig-wasp mutualism

    Science.gov (United States)

    Zhang, Fengping; Peng, Yanqiong; Compton, Stephen G.; Zhao, Yi; Yang, Darong

    2009-04-01

    The Ficus-their specific pollinating fig wasps (Chalcidoidea, Agaonidae) interaction presents a striking example of mutualism. Figs also shelter numerous non-pollinating fig wasps (NPFW) that exploit the fig-pollinator mutualism. Only a few NPFW species can enter figs to oviposit, they do not belong to the pollinating lineage Agaonidae. The internally ovipositing non-agaonid fig wasps can efficiently pollinate the Ficus species that were passively pollinated. However, there is no study to focus on the net effect of these internally ovipositing non-agaonid wasps in actively pollinated Ficus species. By collecting the data of fig wasp community and conducting controlled experiments, our results showed that internally ovipositing Diaziella bizarrea cannot effectively pollinate Ficus glaberrima, an actively pollinated monoecious fig tree. Furthermore, D. bizarrea failed to reproduce if they were introduced into figs without Eupristina sp., the regular pollinator, as all the figs aborted. Furthermore, although D. bizarrea had no effect on seed production in shared figs, it significantly reduced the number of Eupristina sp. progeny emerging from them. Thus, our experimental evidence shows that reproduction in Diaziella depends on the presence of agaonid pollinators, and whether internally ovipositing parasites can act as pollinators depends on the host fig’s pollination mode (active or passive). Overall, this study and others suggest a relatively limited mutualistic role for internally ovipositing fig wasps from non-pollinator (non-Agaonidae) lineages.

  2. The natural history of pollination and mating in bird-pollinated Babiana (Iridaceae)

    Science.gov (United States)

    de Waal, Caroli; Anderson, Bruce; Barrett, Spencer C. H.

    2012-01-01

    Background and Aims Floral variation, pollination biology and mating patterns were investigated in sunbird-pollinated Babiana (Iridaceae) species endemic to the Western Cape of South Africa. The group includes several taxa with specialized bird perches and it has been proposed that these function to promote cross-pollination. Methods Pollinator observations were conducted in 12 populations of five taxa (B. ringens subspp. ringens, australis, B. hirsuta, B. avicularis, B. carminea) and geographic variation in morphological traits investigated in the widespread B. ringens. Experimental pollinations were used to determine the compatibility status, facility for autonomous self-pollination and intensity of pollen limitation in six populations of four taxa. Allozyme markers were employed to investigate mating patterns in four populations of three species. Key Results Sunbirds were the primary pollinators of the five Babiana taxa investigated. Correlated geographical variation in perch size, flower size and stigma–anther separation was evident among B. ringens populations. Experimental pollinations demonstrated that B. ringens and B. avicularis were self-compatible with variation in levels of autonomous self-pollination and weak or no pollen limitation of seed set. In contrast, B. hirsuta was self-incompatible and chronically pollen limited. Estimates of outcrossing rate indicated mixed mating with substantial self-fertilization in all species investigated. Conclusions Despite the possession of specialized bird perches in B. ringens and B. avicularis, these structures do not prevent considerable selfing from occurring, probably as a result of autonomous self-pollination. In eastern populations of B. ringens, smaller flowers and reduced herkogamy appear to be associated with a shift to predominant selfing. Relaxed selection on perch function due to increased selfing may explain the increased incidence of apical flowers in some populations. PMID:21831856

  3. Using Pollination Deficits to Infer Pollinator Declines: Can Theory Guide Us?

    Directory of Open Access Journals (Sweden)

    James D. Thomson

    2001-06-01

    Full Text Available Authors examining pollinator declines frequently discuss pollination deficits, either as contemporary evidence that declines have occurred or as a possible negative consequence of future declines. Because pollination deficits can be measured in short-term studies, it would be useful if such studies could somehow replace painstaking documentation of insect population trends. I examine the legitimacy of this type of substitution with reference to evolutionary theory and natural plant populations. Operationally, pollination deficits are detected through pollen supplementation experiments. Although simple, these experiments are subject to subtleties of interpretation because of biases and nonlinear responses, which I discuss. Although it has been found that, in 62% of the natural populations studied, fruit or seed sets are at least sometimes limited by insufficient pollen, other research suggests that intact natural systems ought to arrive at an evolutionary equilibrium in which reproduction is limited equally by pollination and by maternal resources. Therefore, chronic severe pollination deficits may indicate that the pollinator service of a plant population has declined from some higher level in the past. However, there is no evidence of widespread declines, and, because of stochastic factors in nature, occasional shortfalls of pollination should be expected even at equilibrium. Although the effects of pollination deficits on plant population dynamics have been little studied, moderate declines in seed production may have relatively little effect on population growth rates because resources not expended on fruits and seeds may be reallocated to vegetative persistence or spread. It is therefore premature to conclude that pollinator declines are having strong effects on natural plant populations, but this mostly reflects a lack of data and is no cause for complacency. Theory must be supplemented by case studies; I give one example and

  4. Genome-wide sequence data suggest the possibility of pollinator sharing by host shift in dioecious figs (Moraceae, Ficus).

    Science.gov (United States)

    Wachi, Nakatada; Kusumi, Junko; Tzeng, Hsy-Yu; Su, Zhi-Hui

    2016-11-01

    The obligate mutualism of figs and fig-pollinating wasps has been one of the classic models used for testing theories of co-evolution and cospeciation due to the high species-specificity of these relationships. To investigate the species-specificity between figs and fig pollinators and to further understand the speciation process in obligate mutualisms, we examined the genetic differentiation and phylogenetic relationships of four closely related fig-pollinating wasp species (Blastophaga nipponica, Blastophaga taiwanensis, Blastophaga tannoensis and Blastophaga yeni) in Japan and Taiwan using genome-wide sequence data, including mitochondrial DNA sequences. In addition, population structure was analysed for the fig wasps and their host species using microsatellite data. The results suggest that the three Taiwanese fig wasp species are a single panmictic population that pollinates three dioecious fig species, which are sympatrically distributed, have large differences in morphology and ecology and are also genetically differentiated. Our results illustrate the first case of pollinator sharing by host shift in the subgenus Ficus. On the other hand, there are strict genetic codivergences between allopatric populations of the two host-pollinator pairs. The possible processes that produce these pollinator-sharing events are discussed based on the level and pattern of genetic differentiation in these figs and fig wasps. © 2016 John Wiley & Sons Ltd.

  5. Valuing insect pollination services with cost of replacement.

    Science.gov (United States)

    Allsopp, Mike H; de Lange, Willem J; Veldtman, Ruan

    2008-09-10

    Value estimates of ecosystem goods and services are useful to justify the allocation of resources towards conservation, but inconclusive estimates risk unsustainable resource allocations. Here we present replacement costs as a more accurate value estimate of insect pollination as an ecosystem service, although this method could also be applied to other services. The importance of insect pollination to agriculture is unequivocal. However, whether this service is largely provided by wild pollinators (genuine ecosystem service) or managed pollinators (commercial service), and which of these requires immediate action amidst reports of pollinator decline, remains contested. If crop pollination is used to argue for biodiversity conservation, clear distinction should be made between values of managed- and wild pollination services. Current methods either under-estimate or over-estimate the pollination service value, and make use of criticised general insect and managed pollinator dependence factors. We apply the theoretical concept of ascribing a value to a service by calculating the cost to replace it, as a novel way of valuing wild and managed pollination services. Adjusted insect and managed pollinator dependence factors were used to estimate the cost of replacing insect- and managed pollination services for the Western Cape deciduous fruit industry of South Africa. Using pollen dusting and hand pollination as suitable replacements, we value pollination services significantly higher than current market prices for commercial pollination, although lower than traditional proportional estimates. The complexity associated with inclusive value estimation of pollination services required several defendable assumptions, but made estimates more inclusive than previous attempts. Consequently this study provides the basis for continued improvement in context specific pollination service value estimates.

  6. Flowering phenology of selected wind pollinated allergenic deciduous tree species

    Directory of Open Access Journals (Sweden)

    Magdalena Kluza-Wieloch

    2012-12-01

    Full Text Available Systematic phenological observations have been carried out in the Dendrological Garden of August Cieszkowski Agricultural University, Park Sołacki, Lasek Golęciński, Przybyszewskiego Street, for two years (2003, 2004. The selected species of deciduous trees, as Betula pendula, Corylus avellana, Platanus x hispanica. There was interdependence between the course of flowering process and weather conditions. Long and frosty winter at the turn of 2002/2003 and subzero mean temperatures in the first quarter of 2003 delayed vegetation. Rapid coming of early spring in the year 2004 accelerate the development of generative organs. Each year spring ground frost during flowering did not inhibit this process. All the investigated tree species are anemophilous and produce large amounts of allergenic pollen grain. They cause allergic reactions throughout the whole period of pollen discharge. Male inflorescences in Corylus avellana, blooming very early, are one of the first plants causing allergic reactions. Betula pendula is the next to bloom, followed by Platanus x hispanica. Observations of phenological phases may provide useful information forecasting the beginning of the period of increased pollen concentration in air.

  7. The role of birds and insects in pollination shifts of Scrophularia (Scrophulariaceae).

    Science.gov (United States)

    Navarro-Pérez, María L; López, Josefa; Fernández-Mazuecos, Mario; Rodríguez-Riaño, Tomás; Vargas, Pablo; Ortega-Olivencia, Ana

    2013-10-01

    The mixed vertebrate-insect pollination system is rare in Holarctic plants. Phylogenetic relationships of 116 Scrophularia taxa were investigated based on two plastid (ndhF and trnL-trnF) and one nuclear (ITS) DNA regions. A wider time-calibrated analysis of ndhF sequences of the Lamiales revealed that Scrophularia diverged as early as in the Miocene (<22 Ma). Results of maximum-likelihood optimizations supported wasp pollination as the ancestral pollination system from which other systems derived (hoverfly, mixed vertebrate-insect and bird systems). Four origins for a mixed vertebrate-insect (MVI) pollination system were inferred, in which two western Mediterranean species (S. sambucifolia and S. grandiflora) and two island species (the Tirrenian S. trifoliata and the Canarian S. calliantha) were involved. S. calliantha is the only species in which a more complex MVI system, including pollination by the lizard Gallotia stehlini, has evolved. In addition, bird (hummingbird) floral traits found in the New Mexican S. macrantha appear to have been independently acquired. In contrast, we failed to find evidence for an ancient role of hummingbirds in the evolution of European Scrophularia. Indeed, paleontological data revealed that extinction of European hummingbirds (30-32 Ma) occurred earlier than the divergence of European MVI lineages of Scrophularia. In conclusion, our results showed that a role of birds in pollination of Scrophularia may not have been effective in the Miocene-Pliocene, but bird pollination that shows its origin in the Pliocene-Pleistocene is still operating independently in different islands and continents. Copyright © 2013 Elsevier Inc. All rights reserved.

  8. Pollination biology of basal angiosperms (ANITA grade).

    Science.gov (United States)

    Thien, Leonard B; Bernhardt, Peter; Devall, Margaret S; Chen, Zhi-Duan; Luo, Yi-Bo; Fan, Jian-Hua; Yuan, Liang-Chen; Williams, Joseph H

    2009-01-01

    The first three branches of the angiosperm phylogenetic tree consist of eight families with ∼201 species of plants (the ANITA grade). The oldest flower fossil for the group is dated to the Early Cretaceous (115-125 Mya) and identified to the Nymphaeales. The flowers of extant plants in the ANITA grade are small, and pollen is the edible reward (rarely nectar or starch bodies). Unlike many gymnosperms that secrete "pollination drops," ANITA-grade members examined thus far have a dry-type stigma. Copious secretions of stigmatic fluid are restricted to the Nymphaeales, but this is not nectar. Floral odors, floral thermogenesis (a resource), and colored tepals attract insects in deceit-based pollination syndromes throughout the first three branches of the phylogenetic tree. Self-incompatibility and an extragynoecial compitum occur in some species in the Austrobaileyales. Flies are primary pollinators in six families (10 genera). Beetles are pollinators in five families varying in importance as primary (exclusive) to secondary vectors of pollen. Bees are major pollinators only in the Nymphaeaceae. It is hypothesized that large flowers in Nymphaeaceae are the result of the interaction of heat, floral odors, and colored tepals to trap insects to increase fitness.

  9. Pollinator-prey conflict in carnivorous plants.

    Science.gov (United States)

    Jürgens, Andreas; Sciligo, Amber; Witt, Taina; El-Sayed, Ashraf M; Suckling, D Max

    2012-08-01

    Most carnivorous plants utilize insects in two ways: the flowers attract insects as pollen vectors for sexual reproduction, and the leaves trap insects for nutrients. Feeding on insects has been explained as an adaptation to nutrient-poor soil, and carnivorous plants have been shown to benefit from insect capture through increased growth, earlier flowering and increased seed production. Most carnivorous plant species seem to benefit from insect pollination, although many species autonomously self-pollinate and some propagate vegetatively. However, assuming that outcross pollen is advantageous and is a more important determinant of reproductive success than the nutrients gained from prey, there should be a selective pressure on carnivorous plants not to feed on their potential pollen vectors. Therefore, it has been suggested that carnivorous plants are subject to a conflict, often called the pollinator-prey conflict (PPC). The conflict results from a trade-off of the benefits from feeding on potentially pollinating insects versus the need to use them as pollen vectors for sexual reproduction. In this review we analyze the conditions under which a PPC may occur, review the evidence for the existence of PPCs in carnivorous plants, and explore the mechanisms that may be in place to prevent or alleviate a PPC. With respect to the latter, we discuss how plant signals such as olfactory and visual cues may play a role in separating the functions of pollinator attraction and prey capture. © 2011 The Authors. Biological Reviews © 2011 Cambridge Philosophical Society.

  10. Wild pollinators enhance oilseed rape yield in small-holder farming systems in China

    NARCIS (Netherlands)

    Zou, Yi; Xiao, Haijun; Bianchi, Felix J.J.A.; Jauker, Frank; Luo, Shudong; Werf, van der Wopke

    2017-01-01

    Background: Insect pollinators play an important role in crop pollination, but the relative contribution of wild pollinators and honey bees to pollination is currently under debate. There is virtually no information available on the strength of pollination services and the identity of pollination

  11. Indirect effects of mutualism: ant-treehopper associations deter pollinators and reduce reproduction in a tropical shrub.

    Science.gov (United States)

    Ibarra-Isassi, Javier; Oliveira, Paulo S

    2018-03-01

    Animal-pollinated plants can be susceptible to changes in pollinator availability. Honeydew-producing treehoppers frequently occur on inflorescences, potentially enhancing ant-mediated negative effects on pollination services. However, the effect of ant-attended, honeydew-producing insects on plant reproduction remains uncertain. We recorded the abundance of treehoppers and ants on Byrsonima intermedia (Malpighiaceae), and monitored floral visitors in a Brazilian cerrado savanna. We manipulated the presence of ants and ant-treehopper associations on inflorescences to assess their effect on pollination and fruit formation. We used dried ants pinned to inflorescences to evaluate the effect of ant presence and ant identity on potential pollinators. Results show that the presence of treehoppers increases ant abundance on flowers and disrupts pollination by oil-collecting bees, decreasing the frequency and duration of floral visits and reducing fruit and seed set. Treehopper herbivory has no direct effect on fruit or seed production, which are independent of treehopper density. Pinned ants promote avoidance by floral visitors, reducing the number of visits. Ant identity mediates visitation decisions, with Ectatomma brunneum causing greater avoidance by floral visitors than Camponotus rufipes. Field videos show that pollinating bees are harassed by ants near flowers, prompting avoidance behavior by the bees. This is the first demonstration of indirect effects by honeydew-gathering ants, via disrupted pollination, on plant reproduction in tropical cerrado savanna. Our results highlight the importance of studying other interactions near flowers, in addition to just observing pollinators, for a proper understanding of plant reproduction.

  12. Examination of a Managed Pollinator Strategy for Almond Production Using Apis mellifera (Hymenoptera: Apidae) and Osmia lignaria (Hymenoptera: Megachilidae).

    Science.gov (United States)

    Pitts-Singer, Theresa L; Artz, Derek R; Peterson, Stephen S; Boyle, Natalie K; Wardell, Gordon I

    2018-02-17

    Pollination services provided by managed bees are essential for California almond (Prunus dulcis Mill.; Rosales: Rosaceae) production. Currently, pollination needs are met by rented or owned Apis mellifera L. (Hymenoptera: Apidae; honey bee) colonies. Excessive demand on a challenged A. mellifera industry to provide strong colonies in early spring has caused sharp increases in rental prices over the past decade, inviting the consideration of alternative pollinators in addition to, or in place of, A. mellifera. Osmia lignaria Say (Hymenoptera: Megachilidae; the blue orchard bee) is an excellent pollinator of fruit and nut trees, but its pollination impacts when used in tandem with A. mellifera have yet to be evaluated in commercial almond orchards. A 2-yr study was conducted in California orchards to compare almond pollination and production using A. mellifera as sole pollinator to an alternative practice of adding O. lignaria as a co-pollinator with A. mellifera. Almond orchard managerial decisions, such as for pesticide use and irrigation intensity, vary between almond growing regions because of local climates. Therefore, both north-central and southern sites of California's San Joaquin Valley are represented. We compared bee visitation, nut set, and nut yield between orchards and between tree rows within orchards. Also, O. lignaria reproductive success was recorded to assure that these bees remained in the orchards as pollinators and to assess the ability to sustain these bees under regional orchard conditions. We demonstrated that augmenting large commercial almond orchards with O. lignaria can significantly increase nut set and sometimes nut yield in both regions evaluated.

  13. Biodiversity Economics: The Value of Pollination Services to Egypt ...

    African Journals Online (AJOL)

    made intensification in land use, including the use of pesticides and fertilizers. The majority of wild and crop plants are fully or partially dependent on pollinators for their reproduction. Loss of pollinators has already caused measurable declines in ...

  14. Pollinator population size and pollination ecosystem service responses to enhancing floral and nesting resources.

    Science.gov (United States)

    Häussler, Johanna; Sahlin, Ullrika; Baey, Charlotte; Smith, Henrik G; Clough, Yann

    2017-03-01

    Modeling pollination ecosystem services requires a spatially explicit, process-based approach because they depend on both the behavioral responses of pollinators to the amount and spatial arrangement of habitat and on the within- and between-season dynamics of pollinator populations in response to land use. We describe a novel pollinator model predicting flower visitation rates by wild central-place foragers (e.g., nesting bees) in spatially explicit landscapes. The model goes beyond existing approaches by: (1) integrating preferential use of more rewarding floral and nesting resources; (2) considering population growth over time; (3) allowing different dispersal distances for workers and reproductives; (4) providing visitation rates for use in crop pollination models. We use the model to estimate the effect of establishing grassy field margins offering nesting resources and a low quantity of flower resources, and/or late-flowering flower strips offering no nesting resources but abundant flowers, on bumble bee populations and visitation rates to flowers in landscapes that differ in amounts of linear seminatural habitats and early mass-flowering crops. Flower strips were three times more effective in increasing pollinator populations and visitation rates than field margins, and this effect increased over time. Late-blooming flower strips increased early-season visitation rates, but decreased visitation rates in other late-season flowers. Increases in population size over time in response to flower strips and amounts of linear seminatural habitats reduced this apparent competition for pollinators. Our spatially explicit, process-based model generates emergent patterns reflecting empirical observations, such that adding flower resources may have contrasting short- and long-term effects due to apparent competition for pollinators and pollinator population size increase. It allows exploring these effects and comparing effect sizes in ways not possible with other

  15. Contrasting Pollinators and Pollination in Native and Non-Native Regions of Highbush Blueberry Production.

    Science.gov (United States)

    Gibbs, Jason; Elle, Elizabeth; Bobiwash, Kyle; Haapalainen, Tiia; Isaacs, Rufus

    2016-01-01

    Highbush blueberry yields are dependent on pollination by bees, and introduction of managed honey bees is the primary strategy used for pollination of this crop. Complementary pollination services are also provided by wild bees, yet highbush blueberry is increasingly grown in regions outside its native range where wild bee communities may be less adapted to the crop and growers may still be testing appropriate honey bee stocking densities. To contrast crop pollination in native and non-native production regions, we sampled commercial 'Bluecrop' blueberry fields in British Columbia and Michigan with grower-selected honey bee stocking rates (0-39.5 hives per ha) to compare bee visitors to blueberry flowers, pollination and yield deficits, and how those vary with local- and landscape-scale factors. Observed and Chao-1 estimated species richness, as well as Shannon diversity of wild bees visiting blueberries were significantly higher in Michigan where the crop is within its native range. The regional bee communities were also significantly different, with Michigan farms having greater dissimilarity than British Columbia. Blueberry fields in British Columbia had fewer visits by honey bees than those in Michigan, irrespective of stocking rate, and they also had lower berry weights and a significant pollination deficit. In British Columbia, pollination service increased with abundance of wild bumble bees, whereas in Michigan the abundance of honey bees was the primary predictor of pollination. The proportion of semi-natural habitat at local and landscape scales was positively correlated with wild bee abundance in both regions. Wild bee abundance declined significantly with distance from natural borders in Michigan, but not in British Columbia where large-bodied bumble bees dominated the wild bee community. Our results highlight the varying dependence of crop production on different types of bees and reveal that strategies for pollination improvement in the same crop can

  16. Contrasting Pollinators and Pollination in Native and Non-Native Regions of Highbush Blueberry Production.

    Directory of Open Access Journals (Sweden)

    Jason Gibbs

    Full Text Available Highbush blueberry yields are dependent on pollination by bees, and introduction of managed honey bees is the primary strategy used for pollination of this crop. Complementary pollination services are also provided by wild bees, yet highbush blueberry is increasingly grown in regions outside its native range where wild bee communities may be less adapted to the crop and growers may still be testing appropriate honey bee stocking densities. To contrast crop pollination in native and non-native production regions, we sampled commercial 'Bluecrop' blueberry fields in British Columbia and Michigan with grower-selected honey bee stocking rates (0-39.5 hives per ha to compare bee visitors to blueberry flowers, pollination and yield deficits, and how those vary with local- and landscape-scale factors. Observed and Chao-1 estimated species richness, as well as Shannon diversity of wild bees visiting blueberries were significantly higher in Michigan where the crop is within its native range. The regional bee communities were also significantly different, with Michigan farms having greater dissimilarity than British Columbia. Blueberry fields in British Columbia had fewer visits by honey bees than those in Michigan, irrespective of stocking rate, and they also had lower berry weights and a significant pollination deficit. In British Columbia, pollination service increased with abundance of wild bumble bees, whereas in Michigan the abundance of honey bees was the primary predictor of pollination. The proportion of semi-natural habitat at local and landscape scales was positively correlated with wild bee abundance in both regions. Wild bee abundance declined significantly with distance from natural borders in Michigan, but not in British Columbia where large-bodied bumble bees dominated the wild bee community. Our results highlight the varying dependence of crop production on different types of bees and reveal that strategies for pollination improvement in

  17. Large Carpenter Bees as Agricultural Pollinators

    Directory of Open Access Journals (Sweden)

    Tamar Keasar

    2010-01-01

    Full Text Available Large carpenter bees (genus Xylocopa are wood-nesting generalist pollinators of broad geographical distribution that exhibit varying levels of sociality. Their foraging is characterized by a wide range of food plants, long season of activity, tolerance of high temperatures, and activity under low illumination levels. These traits make them attractive candidates for agricultural pollination in hot climates, particularly in greenhouses, and of night-blooming crops. Carpenter bees have demonstrated efficient pollination service in passionflower, blueberries, greenhouse tomatoes and greenhouse melons. Current challenges to the commercialization of these attempts lie in the difficulties of mass-rearing Xylocopa, and in the high levels of nectar robbing exhibited by the bees.

  18. Pollen analyses for pollination research, acetolysis

    Directory of Open Access Journals (Sweden)

    Gretchen D. Jones

    2014-08-01

    Full Text Available Analysis of the pollen associated with pollinators can reveal their role in pollination, the habitats and plants they visit, from where they migrated, what they eat, and dispersal patterns in and around cropping systems. However, finding pollen on and or in a pollinator depends on the technique used to recover the pollen. Acetolysis can be used to recover pollen from internal insect tissues (gut, alimentary canal, crop, etc., external tissues (proboscis, legs, eyes, etc. or both. Acetolysis is the best technique for recovering pollen because any tissue is dissolved and lipids and debris are removed from the sample and the pollen grains. This makes the diagnostic characteristics of the pollen grains more visible so that accurate pollen identification can be made. By using the proper technique, better pollen recovery can be made and thus better data can be obtained.

  19. Nest management increases pollinator density in passion fruit orchards

    OpenAIRE

    Junqueira, Camila; Yamamoto, Marcela; Oliveira, Paulo; Hogendoorn, Katja; Augusto, Solange

    2013-01-01

    International audience; The yields of yellow passion fruit are vulnerable to pollinator decline because the crop is strictly self-incompatible. Nectar foraging carpenter bees are the main pollinators of this crop, whereas honeybees and stingless bees take pollen and nectar without pollination, and can be classified as “thieves”. In many cropping areas, the density of effective pollinators is very low and precludes optimal yield. We investigated, over a period of 6 months, whether the provisio...

  20. Wind energy

    CERN Document Server

    Woll, Kris

    2016-01-01

    Across the country, huge open spaces are covered in gently turning wind turbines. In Wind Energy, explore how these machines generate electricity, learn about the history of wind power, and discover the latest advances in the field. Easy-to-read text, vivid images, and helpful back matter give readers a clear look at this subject. Features include a table of contents, infographics, a glossary, additional resources, and an index. Aligned to Common Core Standards and correlated to state standards. Core Library is an imprint of Abdo Publishing, a division of ABDO.

  1. Bimodal pollination system of the bromeliad Aechmea nudicaulis involving hummingbirds and bees.

    Science.gov (United States)

    Schmid, S; Schmid, V S; Zillikens, A; Harter-Marques, B; Steiner, J

    2011-01-01

    In order to compare the effectiveness of birds and insects as pollinators, we studied the floral biology of the bromeliad Aechmea nudicaulis (L.) Grisebach in the biome of the Atlantic rain forest, southern Brazil. On Santa Catarina Island, flowering extends from mid-September to the end of December, with diurnal anthesis. The reproductive system is obligatory xenogamy, thus pollinator-dependent. Flowers secrete 31.84 μl of nectar per day, with a mean sugar concentration of 23.2%. Highest nectar volume and sugar concentration occur at the beginning of anthesis. Most floral traits are characteristic for ornithophily, and nectar production appears to be adapted to the energy demand of hummingbirds. Continued secretion of the sucrose-dominated nectar attracts and binds visitors to inflorescences, strengthening trapline foraging behaviour. Experiments assessing seed set after single flower visits were performed with the most frequent visitors, revealing the hummingbird Thalurania glaucopis as the most effective pollen vector. In addition, bees are also functional pollinators, as substantiated by their high visitation frequency. We conclude that this pollination system is bimodal. Thus, there is redundancy in the pollination service provided by birds and bees, granting a high probability of successful reproduction in Ae. nudicaulis. © 2010 German Botanical Society and The Royal Botanical Society of the Netherlands.

  2. Review. Specificity in pollination and consequences for postmating reproductive isolation in deceptive Mediterranean orchids.

    Science.gov (United States)

    Cozzolino, Salvatore; Scopece, Giovanni

    2008-09-27

    The type of reproductive isolation prevalent in the initial stages of species divergence can affect the nature and rate of emergence of additional reproductive barriers that subsequently strengthen isolation between species. Different groups of Mediterranean deceptive orchids are characterized by different levels of pollinator specificity. Whereas food-deceptive orchid species show weak pollinator specificity, the sexually deceptive Ophrys species display a more specialized pollination strategy. Comparative analyses reveal that orchids with high pollinator specificity mostly rely on premating reproductive barriers and have very little postmating isolation. In this group, a shift to a novel pollinator achieved by modifying the odour bouquet may represent the main isolation mechanism involved in speciation. By contrast, orchids with weak premating isolation, such as generalized food-deceptive orchids, show strong evidence for intrinsic postmating reproductive barriers, particularly for late-acting postzygotic barriers such as hybrid sterility. In such species, chromosomal differences may have played a key role in species isolation, although strong postmating-prezygotic isolation has also evolved in these orchids. Molecular analyses of hybrid zones indicate that the types and strength of reproductive barriers in deceptive orchids with contrasting premating isolation mechanisms directly affect the rate and evolutionary consequences of hybridization and the nature of species differentiation.

  3. Bee diversity effects on pollination depend on functional complementarity and niche shifts.

    Science.gov (United States)

    Fründ, Jochen; Dormann, Carsten F; Holzschuh, Andrea; Tscharntke, Teja

    2013-09-01

    Biodiversity is important for many ecosystem processes. Global declines in pollinator diversity and abundance have been recognized, raising concerns about a pollination crisis of crops and wild plants. However, experimental evidence for effects of pollinator species diversity on plant reproduction is extremely scarce. We established communities with 1-5 bee species to test how seed production of a plant community is determined by bee diversity. Higher bee diversity resulted in higher seed production, but the strongest difference was observed for one compared to more than one bee species. Functional complementarity among bee species had a far higher explanatory power than bee diversity, suggesting that additional bee species only benefit pollination when they increase coverage of functional niches. In our experiment, complementarity was driven by differences in flower and temperature preferences. Interspecific interactions among bee species contributed to realized functional complementarity, as bees reduced interspecific overlap by shifting to alternative flowers in the presence of other species. This increased the number of plant species visited by a bee community and demonstrates a new mechanism for a biodiversity-function relationship ("interactive complementarity"). In conclusion, our results highlight both the importance of bee functional diversity for the reproduction of plant communities and the need to identify complementarity traits for accurately predicting pollination services by different bee communities.

  4. Supporting crop pollinators with floral resources: network-based phenological matching.

    Science.gov (United States)

    Russo, Laura; Debarros, Nelson; Yang, Suann; Shea, Katriona; Mortensen, David

    2013-09-01

    The production of diverse and affordable agricultural crop species depends on pollination services provided by bees. Indeed, the proportion of pollinator-dependent crops is increasing globally. Agriculture relies heavily on the domesticated honeybee; the services provided by this single species are under threat and becoming increasingly costly. Importantly, the free pollination services provided by diverse wild bee communities have been shown to be sufficient for high agricultural yields in some systems. However, stable, functional wild bee communities require floral resources, such as pollen and nectar, throughout their active season, not just when crop species are in flower. To target floral provisioning efforts to conserve and support native and managed bee species, we apply network theoretical methods incorporating plant and pollinator phenologies. Using a two-year dataset comprising interactions between bees (superfamily Apoidea, Anthophila) and 25 native perennial plant species in floral provisioning habitat, we identify plant and bee species that provide a key and central role to the stability of the structure of this community. We also examine three specific case studies: how provisioning habitat can provide temporally continuous support for honeybees (Apis mellifera) and bumblebees (Bombus impatiens), and how resource supplementation strategies might be designed for a single genus of important orchard pollinators (Osmia). This framework could be used to provide native bee communities with additional, well-targeted floral resources to ensure that they not only survive, but also thrive.

  5. Evolution of pollination niches in a generalist plant clade.

    Science.gov (United States)

    Gómez, José María; Perfectti, Francisco; Abdelaziz, Mohamed; Lorite, Juan; Muñoz-Pajares, Antonio Jesús; Valverde, Javier

    2015-01-01

    It is widely assumed that floral diversification occurs by adaptive shifts between pollination niches. In contrast to specialized flowers, identifying pollination niches of generalist flowers is a challenge. Consequently, how generalist pollination niches evolve is largely unknown. We apply tools from network theory and comparative methods to investigate the evolution of pollination niches among generalist species belonging to the genus Erysimum. These species have similar flowers. We found that the studied species may be grouped in several multidimensional niches separated not by a shift of pollinators, but instead by quantitative variation in the relative abundance of pollinator functional groups. These pollination niches did not vary in generalization degree; we did not find any evolutionary trend toward specialization within the studied clade. Furthermore, the evolution of pollination niche fitted to a Brownian motion model without phylogenetic signal, and was characterized by frequent events of niche convergences and divergences. We presume that the evolution of Erysimum pollination niches has occurred mostly by recurrent shifts between slightly different generalized pollinator assemblages varying spatially as a mosaic and without any change in specialization degree. Most changes in pollination niches do not prompt floral divergence, a reason why adaptation to pollinators is uncommon in generalist plants. © 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.

  6. Pollination mechanisms in palms – a synoecological perspective

    DEFF Research Database (Denmark)

    Barfod, Anders S.; Hagen, Melanie; Borchsenius, Finn

    More than 60 pollination ecological studies have been conducted on palms since Henderson’s almost 25 year old review of palm pollination. Most studies are aut-ecological studies that provide a detailed snapshot of the pollination of a limited number of palm individuals of the same species. They c...

  7. Pollination and seedling ecology of Decalepis hamiltonii Wight & Arn. (Periplocaceae, a commercially important, endemic and endangered species

    Directory of Open Access Journals (Sweden)

    A.J.S. Raju

    2009-10-01

    Full Text Available Decalepis hamiltonii is a woody climber and annual bloomer. The flowers are characterized by nectariferous coralline corona, gynostegium and pollinia containing tetrads. The floral features such as greenish white corolla, mild fragrance, flat-shape for easy access to floral rewards, and ovary protection from the biting mouthparts of the pollinator make up cantharophilous pollination syndrome. Brachinus beetle is the principal pollinator. Thrips use floral buds to raise their offspring; they also effect pollination while collecting nectar; but they are important largely for self-pollination due to their short distance flying ability. The plant is a self-incompatible, obligate outcrosser and is substantiated by 2% natural fruit set, but each fruit produces numerous seeds. Fruits dehisce during the dry season and seed dispersal is by wind. Seeds germinate as soon as they fall in a favourable place, but only a small percentage establish seedlings. Over-exploitation, bottlenecks in sexual reproduction and seedling establishment may contribute to the endangered status of D. hamiltonii.

  8. Generalist bees pollinate red-flowered Penstemon eatonii: duality in the hummingbird pollination syndrome

    Science.gov (United States)

    The red tubular flowers of Penstemon eatonii (Plantaginaceae, formerly Scrophulariaceae) conform to the classic pollination syndrome for hummingbirds. This could be problematic when farming this wildflower for rangeland restoration seed. By some models and experiments with nectaring bumblebees at ...

  9. Are long corolla tubes in Pedicularis driven by pollinator selection?

    Science.gov (United States)

    Huang, Shuang-Quan; Wang, Xiang-Ping; Sun, Shi-Guo

    2016-08-01

    The evolution of long corolla tubes has been hypothesized to be driven by long-tongued pollinators. Corolla tubes in Pedicularis species can be longer than 10 cm which may function as flower stalks to increase visual attractiveness to pollinators because these species provide no nectar and are pollinated by bumblebees. The corolla tube length was manipulated (shorter or longer) in two Pedicularis species in field to examine whether longer tubes are more attractive to pollinators and produce more seeds than short tubes. Our results did not support the pollinator attraction hypothesis, leaving the evolution of long tubes in Pedicularis remains mysterious. © 2015 Institute of Botany, Chinese Academy of Sciences.

  10. POTENTIAL POLLINATORS AND FLORAL VISITORS OF ...

    African Journals Online (AJOL)

    Prof. Adipala Ekwamu

    2013-05-06

    May 6, 2013 ... Limited Company, Zambia, and the University of. Zambia. For each flower visit, we also recorded the visitor .... attractiveness of J. curcas flowers to local pollinators might have adverse effect to native flowering .... the financial and logistical support. We appreciate. Fuel crop Demeter farm, Malawi and Ms.

  11. Dealing with complexity in pollination management

    DEFF Research Database (Denmark)

    Sørensen, Peter Borgen; Tscheulin, Thomas; POTTS, Simon G

    Interactions between pollinators and agricultural production are complex to understand and lack of knowledge is, therefore, a challenge for legislation and management. Knowledge tends to be partial and specific to particular systems. Thus, there is a critical need for structural knowledge that can...

  12. Chapter 1: Assessing pollinator habitat services to optimize conservation programs

    Science.gov (United States)

    Iovanna, Richard; Ando , Amy W.; Swinton, Scott; Hellerstein, Daniel; Kagan, Jimmy; Mushet, David M.; Otto, Clint R.; Rewa, Charles A.

    2017-01-01

    Pollination services have received increased attention over the past several years, and protecting foraging area is beginning to be reflected in conservation policy. This case study considers the prospects for doing so in a more analytically rigorous manner, by quantifying the pollination services for sites being considered for ecological restoration. The specific policy context is the Conservation Reserve Program (CRP), which offers financial and technical assistance to landowners seeking to convert sensitive cropland back to some semblance of the prairie (or, to a lesser extent, forest or wetland) ecosystem that preceded it. Depending on the mix of grasses and wildflowers that are established, CRP enrollments can provide pollinator habitat. Further, depending on their location, they will generate related services, such as biological control of crop pests, recreation, and aesthetics. While offers to enroll in CRP compete based on cost and some anticipated benefits, the eligibility and ranking criteria do not reflect these services to a meaningful degree. Therefore, we develop a conceptual value diagram to identify the sequence of steps and associated models and data necessary to quantify the full range of services, and find that critical data gaps, some of which are artifacts of policy, preclude the application of benefit-relevant indicators (BRIs) or monetization. However, we also find that there is considerable research activity underway to fill these gaps. In addition, a modeling framework has been developed that can estimate field-level effects on services as a function of landscape context. The approach is inherently scalable and not limited in geographic scope, which is essential for a program with a national footprint. The parameters in this framework are sufficiently straightforward that expert judgment could be applied as a stopgap approach until empirically derived estimates are available. While monetization of benefit-relevant indicators of yield

  13. Spatial heterogeneity regulates plant-pollinator networks across multiple landscape scales.

    Directory of Open Access Journals (Sweden)

    Eduardo Freitas Moreira

    Full Text Available Mutualistic plant-pollinator interactions play a key role in biodiversity conservation and ecosystem functioning. In a community, the combination of these interactions can generate emergent properties, e.g., robustness and resilience to disturbances such as fluctuations in populations and extinctions. Given that these systems are hierarchical and complex, environmental changes must have multiple levels of influence. In addition, changes in habitat quality and in the landscape structure are important threats to plants, pollinators and their interactions. However, despite the importance of these phenomena for the understanding of biological systems, as well as for conservation and management strategies, few studies have empirically evaluated these effects at the network level. Therefore, the objective of this study was to investigate the influence of local conditions and landscape structure at multiple scales on the characteristics of plant-pollinator networks. This study was conducted in agri-natural lands in Chapada Diamantina, Bahia, Brazil. Pollinators were collected in 27 sampling units distributed orthogonally along a gradient of proportion of agriculture and landscape diversity. The Akaike information criterion was used to select models that best fit the metrics for network characteristics, comparing four hypotheses represented by a set of a priori candidate models with specific combinations of the proportion of agriculture, the average shape of the landscape elements, the diversity of the landscape and the structure of local vegetation. The results indicate that a reduction of habitat quality and landscape heterogeneity can cause species loss and decrease of networks nestedness. These structural changes can reduce robustness and resilience of plant-pollinator networks what compromises the reproductive success of plants, the maintenance of biodiversity and the pollination service stability. We also discuss the possible explanations for

  14. Spatial heterogeneity regulates plant-pollinator networks across multiple landscape scales.

    Science.gov (United States)

    Moreira, Eduardo Freitas; Boscolo, Danilo; Viana, Blandina Felipe

    2015-01-01

    Mutualistic plant-pollinator interactions play a key role in biodiversity conservation and ecosystem functioning. In a community, the combination of these interactions can generate emergent properties, e.g., robustness and resilience to disturbances such as fluctuations in populations and extinctions. Given that these systems are hierarchical and complex, environmental changes must have multiple levels of influence. In addition, changes in habitat quality and in the landscape structure are important threats to plants, pollinators and their interactions. However, despite the importance of these phenomena for the understanding of biological systems, as well as for conservation and management strategies, few studies have empirically evaluated these effects at the network level. Therefore, the objective of this study was to investigate the influence of local conditions and landscape structure at multiple scales on the characteristics of plant-pollinator networks. This study was conducted in agri-natural lands in Chapada Diamantina, Bahia, Brazil. Pollinators were collected in 27 sampling units distributed orthogonally along a gradient of proportion of agriculture and landscape diversity. The Akaike information criterion was used to select models that best fit the metrics for network characteristics, comparing four hypotheses represented by a set of a priori candidate models with specific combinations of the proportion of agriculture, the average shape of the landscape elements, the diversity of the landscape and the structure of local vegetation. The results indicate that a reduction of habitat quality and landscape heterogeneity can cause species loss and decrease of networks nestedness. These structural changes can reduce robustness and resilience of plant-pollinator networks what compromises the reproductive success of plants, the maintenance of biodiversity and the pollination service stability. We also discuss the possible explanations for these relationships and

  15. Floral longevity and autonomous selfing are altered by pollination and water availability in Collinsia heterophylla.

    Science.gov (United States)

    Jorgensen, Rachael; Arathi, H S

    2013-09-01

    A plant investing in reproduction partitions resources between flowering and seed production. Under resource limitation, altered allocations may result in floral trait variations, leading to compromised fecundity. Floral longevity and timing of selfing are often the traits most likely to be affected. The duration of corolla retention determines whether fecundity results from outcrossing or by delayed selfing-mediated reproductive assurance. In this study, the role of pollination schedules and soil water availability on floral longevity and seed production is tested in Collinsia heterophylla (Plantaginaceae). Using three different watering regimes and pollination schedules, effects on floral longevity and seed production were studied in this protandrous, flowering annual. The results reveal that soil water status and pollination together influence floral longevity with low soil water and hand-pollinations early in the floral lifespan reducing longevity. However, early pollinations under excess water did not extend longevity, implying that resource surplus does not lengthen the outcrossing period. The results also indicate that pollen receipt, a reliable cue for fecundity, accelerates flower drop. Early corolla abscission under drought stress could potentially exacerbate sexual conflict in this protandrous, hermaphroditic species by ensuring self-pollen paternity and enabling male control of floral longevity. While pollination schedules did not affect fecundity, water stress reduced per-capita seed numbers. Unmanipulated flowers underwent delayed autonomous selfing, producing very few seeds, suggesting that inbreeding depression may limit benefits of selfing. In plants where herkogamy and dichogamy facilitate outcrossing, floral longevity determines reproductive success and mating system. Reduction in longevity under drought suggests a strong environmental effect that could potentially alter the preferred breeding mode in this mixed-mated species. Extrapolating the

  16. Effects of landscape composition and configuration on pollination in a native herb: a field experiment.

    Science.gov (United States)

    Ekroos, Johan; Jakobsson, Anna; Wideen, Joel; Herbertsson, Lina; Rundlöf, Maj; Smith, Henrik G

    2015-10-01

    Bumble bee abundance in agricultural landscapes is known to decrease with increasing distance from seminatural grasslands, but whether the pollination of bumble-bee-pollinated wild plants shows a similar pattern is less well known. In addition, the relative effects of landscape composition (landscape heterogeneity) and landscape configuration (distance from seminatural grassland) on wild plant pollination, and the interaction between these landscape effects, have not been studied using landscape-level replication. We performed a field experiment to disentangle these landscape effects on the pollination of a native herb, the sticky catchfly (Lychnis viscaria), while accounting for the proportion of oilseed rape across landscapes and the local abundance of bee forage flowers. We measured pollen limitation (the degree to which seed set is pollen-limited), seed set, and seed set stability using potted plants placed in landscapes that differed in heterogeneity (composition) and distance from seminatural grassland (configuration). Pollen limitation and seed set in individual plants did not respond to landscape composition, landscape configuration, or proportion of oilseed rape. Instead, seed set increased with increasing local bee forage flower cover. However, we found within-plant variability in pollen limitation and seed set to increase with increasing distance from seminatural pasture. Our results suggest that average within-plant levels of pollen limitation and seed set respond less swiftly than the within-plant variability in pollen limitation and seed set to changes in landscape configuration. Although landscape effects on pollination were less important than predicted, we conclude that landscape configuration and local habitat characteristics play larger roles than landscape composition in the pollination of L. viscaria.

  17. Spatial Heterogeneity Regulates Plant-Pollinator Networks across Multiple Landscape Scales

    Science.gov (United States)

    Moreira, Eduardo Freitas; Boscolo, Danilo; Viana, Blandina Felipe

    2015-01-01

    Mutualistic plant-pollinator interactions play a key role in biodiversity conservation and ecosystem functioning. In a community, the combination of these interactions can generate emergent properties, e.g., robustness and resilience to disturbances such as fluctuations in populations and extinctions. Given that these systems are hierarchical and complex, environmental changes must have multiple levels of influence. In addition, changes in habitat quality and in the landscape structure are important threats to plants, pollinators and their interactions. However, despite the importance of these phenomena for the understanding of biological systems, as well as for conservation and management strategies, few studies have empirically evaluated these effects at the network level. Therefore, the objective of this study was to investigate the influence of local conditions and landscape structure at multiple scales on the characteristics of plant-pollinator networks. This study was conducted in agri-natural lands in Chapada Diamantina, Bahia, Brazil. Pollinators were collected in 27 sampling units distributed orthogonally along a gradient of proportion of agriculture and landscape diversity. The Akaike information criterion was used to select models that best fit the metrics for network characteristics, comparing four hypotheses represented by a set of a priori candidate models with specific combinations of the proportion of agriculture, the average shape of the landscape elements, the diversity of the landscape and the structure of local vegetation. The results indicate that a reduction of habitat quality and landscape heterogeneity can cause species loss and decrease of networks nestedness. These structural changes can reduce robustness and resilience of plant-pollinator networks what compromises the reproductive success of plants, the maintenance of biodiversity and the pollination service stability. We also discuss the possible explanations for these relationships and

  18. Community-wide assessment of pollen limitation in hummingbird-pollinated plants of a tropical montane rain forest.

    Science.gov (United States)

    Wolowski, Marina; Ashman, Tia-Lynn; Freitas, Leandro

    2013-09-01

    Although pollen limitation of reproduction (PL) has been widely studied, our understanding of its occurrence in tropical communities, especially for bird-pollinated plants, is underdeveloped. In addition, inclusion of both quantity and quality aspects in studies of PL are generally lacking. Within hummingbird-pollinated plants, a prediction was made for higher PL for the quality than quantity aspects and a minor effect of temporal variation because hummingbirds are constant and efficient pollen vectors but they may transfer low quality pollen. Field hand and open pollination experiments were conducted on 21 species in a tropical montane rain forest over 2 years. The quantity (fruit set and seeds per fruit) and quality (seed weight and germination) aspects of reproduction were assessed as the response to open pollination relative to outcross hand pollination. The relationships between the effect size of quantity and quality aspects of reproduction and predictive plant features (self-incompatibility, autogamy, density and pollinator specialization level) were assessed with phylogenetic generalized linear models. Just over half of all the species expressed PL for one or more response variables. On average, the severity of PL was strong for one quality variable (seed germination; 0·83), but insignificant for another (seed weight; -0·03), and low to moderate for quantity variables (0·31 for seeds per fruit and 0·39 for fruit set). There was only a minor contribution of temporal variation to PL within the studied species. Common predictors of PL, i.e. phylogenetic relatedness, self-incompatibility, autogamy, plant density and pollinator specialization level, did not adequately explain variation in PL within this community. Despite the measurable degree of PL within these hummingbird-pollinated plants, the causes of pollen quality and quantity insufficiency are not clear. Variables other than those tested may contribute to PL or causes of PL may vary among species and

  19. Transcriptome profiling reveals the regulatory mechanism underlying pollination dependent and parthenocarpic fruit set mainly mediated by auxin and gibberellin.

    Science.gov (United States)

    Tang, Ning; Deng, Wei; Hu, Guojian; Hu, Nan; Li, Zhengguo

    2015-01-01

    Fruit set is a key process for crop production in tomato which occurs after successful pollination and fertilization naturally. However, parthenocarpic fruit development can be uncoupled from fertilization triggered by exogenous auxin or gibberellins (GAs). Global transcriptome knowledge during fruit initiation would help to characterize the molecular mechanisms by which these two hormones regulate pollination-dependent and -independent fruit set. In this work, digital gene expression tag profiling (DGE) technology was applied to compare the transcriptomes from pollinated and 2, 4-D/GA3-treated ovaries. Activation of carbohydrate metabolism, cell division and expansion as well as the down-regulation of MADS-box is a comprehensive regulatory pathway during pollination-dependent and parthenocarpic fruit set. The signaling cascades of auxin and GA are significantly modulated. The feedback regulations of Aux/IAAs and DELLA genes which functioned to fine-tune auxin and GA response respectively play fundamental roles in triggering fruit initiation. In addition, auxin regulates GA synthesis via up-regulation of GA20ox1 and down-regulation of KNOX. Accordingly, the effect of auxin on fruit set is mediated by GA via ARF2 and IAA9 down-regulation, suggesting that both pollination-dependent and parthenocarpic fruit set depend on the crosstalk between auxin and GA. This study characterizes the transcriptomic features of ovary development and more importantly unravels the integral roles of auxin and GA on pollination-dependent and parthenocarpic fruit set.

  20. Transcriptome profiling reveals the regulatory mechanism underlying pollination dependent and parthenocarpic fruit set mainly mediated by auxin and gibberellin.

    Directory of Open Access Journals (Sweden)

    Ning Tang

    Full Text Available Fruit set is a key process for crop production in tomato which occurs after successful pollination and fertilization naturally. However, parthenocarpic fruit development can be uncoupled from fertilization triggered by exogenous auxin or gibberellins (GAs. Global transcriptome knowledge during fruit initiation would help to characterize the molecular mechanisms by which these two hormones regulate pollination-dependent and -independent fruit set.In this work, digital gene expression tag profiling (DGE technology was applied to compare the transcriptomes from pollinated and 2, 4-D/GA3-treated ovaries. Activation of carbohydrate metabolism, cell division and expansion as well as the down-regulation of MADS-box is a comprehensive regulatory pathway during pollination-dependent and parthenocarpic fruit set. The signaling cascades of auxin and GA are significantly modulated. The feedback regulations of Aux/IAAs and DELLA genes which functioned to fine-tune auxin and GA response respectively play fundamental roles in triggering fruit initiation. In addition, auxin regulates GA synthesis via up-regulation of GA20ox1 and down-regulation of KNOX. Accordingly, the effect of auxin on fruit set is mediated by GA via ARF2 and IAA9 down-regulation, suggesting that both pollination-dependent and parthenocarpic fruit set depend on the crosstalk between auxin and GA.This study characterizes the transcriptomic features of ovary development and more importantly unravels the integral roles of auxin and GA on pollination-dependent and parthenocarpic fruit set.

  1. The pollination of a self-incompatible, food-mimic orchid, Coelogyne fimbriata (Orchidaceae), by female Vespula wasps

    Science.gov (United States)

    Cheng, Jin; Shi, Jun; Shangguan, Fa-Zhi; Dafni, Amots; Deng, Zhen-Hai; Luo, Yi-Bo

    2009-01-01

    Background and Aims The study of specialized interactions between species is crucial to our understanding of processes in evolutionary ecology due to their profound effect on life cycles and diversification. Obligate pollination by a single wasp species is rare in Orchidaceae except in species with sexually deceptive flowers that are pollinated exclusively by male insects. The object of this study was to document pollination of the food-deceptive flowers of Coelogyne fimbriata, a species pollinated exclusively by female wasps. Methods Field observations and experiments were conducted in two populations of C. fimbriata. Floral phenology was recorded, and functional floral architecture was measured. Insect visitors to flowers were observed from 2005 to 2007. Bioassay experiments were conducted to check whether the floral odour attracted pollinators. Natural (insect-mediated) rates of pollinarium removal, pollinium deposition on stigmas, and fruit set were recorded. To determine the importance of cross-pollination, the breeding system was assessed via controlled, hand-pollination experiments. Key Results Two populations of C. fimbriata with fragrant, nectarless flowers are pollinated by females of the same Vespula species (Vespidae, Hymenoptera). Experiments on wasps show that they crawl towards the source of the odour. The flowering period appears to coincide with an annual peak in Vespula colony expansion when additional workers forage for carbohydrates. Rates of pollinarium removal (0·069–0·918) and pollinium deposition on stigmas (0·025–0·695) are extremely variable. However, fruit set in C. fimbriata is always low (0·014–0·069) and appears to be based on self-incompatibility coupled with intraclonal (geitonogamous) deposition of pollinia. Conclusions Coelogyne fimbriata and Steveniella satyrioides are now the only orchid species known to have food-deceptive flowers that are pollinated exclusively by eusocial, worker wasps. In C. fimbriata, floral

  2. Ecology and evolution of plant-pollinator interactions.

    Science.gov (United States)

    Mitchell, Randall J; Irwin, Rebecca E; Flanagan, Rebecca J; Karron, Jeffrey D

    2009-06-01

    Some of the most exciting advances in pollination biology have resulted from interdisciplinary research combining ecological and evolutionary perspectives. For example, these two approaches have been essential for understanding the functional ecology of floral traits, the dynamics of pollen transport, competition for pollinator services, and patterns of specialization and generalization in plant-pollinator interactions. However, as research in these and other areas has progressed, many pollination biologists have become more specialized in their research interests, focusing their attention on either evolutionary or ecological questions. We believe that the continuing vigour of a synthetic and interdisciplinary field like pollination biology depends on renewed connections between ecological and evolutionary approaches. In this Viewpoint paper we highlight the application of ecological and evolutionary approaches to two themes in pollination biology: (1) links between pollinator behaviour and plant mating systems, and (2) generalization and specialization in pollination systems. We also describe how mathematical models and synthetic analyses have broadened our understanding of pollination biology, especially in human-modified landscapes. We conclude with several suggestions that we hope will stimulate future research. This Viewpoint also serves as the introduction to this Special Issue on the Ecology and Evolution of Plant-Pollinator Interactions. These papers provide inspiring examples of the synergy between evolutionary and ecological approaches, and offer glimpses of great accomplishments yet to come.

  3. Experimental evidence that wildflower strips increase pollinator visits to crops.

    Science.gov (United States)

    Feltham, Hannah; Park, Kirsty; Minderman, Jeroen; Goulson, Dave

    2015-08-01

    Wild bees provide a free and potentially diverse ecosystem service to farmers growing pollination-dependent crops. While many crops benefit from insect pollination, soft fruit crops, including strawberries are highly dependent on this ecosystem service to produce viable fruit. However, as a result of intensive farming practices and declining pollinator populations, farmers are increasingly turning to commercially reared bees to ensure that crops are adequately pollinated throughout the season. Wildflower strips are a commonly used measure aimed at the conservation of wild pollinators. It has been suggested that commercial crops may also benefit from the presence of noncrop flowers; however, the efficacy and economic benefits of sowing flower strips for crops remain relatively unstudied. In a study system that utilizes both wild and commercial pollinators, we test whether wildflower strips increase the number of visits to adjacent commercial strawberry crops by pollinating insects. We quantified this by experimentally sowing wildflower strips approximately 20 meters away from the crop and recording the number of pollinator visits to crops with, and without, flower strips. Between June and August 2013, we walked 292 crop transects at six farms in Scotland, recording a total of 2826 pollinators. On average, the frequency of pollinator visits was 25% higher for crops with adjacent flower strips compared to those without, with a combination of wild and commercial bumblebees (Bombus spp.) accounting for 67% of all pollinators observed. This effect was independent of other confounding effects, such as the number of flowers on the crop, date, and temperature. Synthesis and applications. This study provides evidence that soft fruit farmers can increase the number of pollinators that visit their crops by sowing inexpensive flower seed mixes nearby. By investing in this management option, farmers have the potential to increase and sustain pollinator populations over time.

  4. Artificial light at night as a new threat to pollination.

    Science.gov (United States)

    Knop, Eva; Zoller, Leana; Ryser, Remo; Gerpe, Christopher; Hörler, Maurin; Fontaine, Colin

    2017-08-10

    Pollinators are declining worldwide and this has raised concerns for a parallel decline in the essential pollination service they provide to both crops and wild plants. Anthropogenic drivers linked to this decline include habitat changes, intensive agriculture, pesticides, invasive alien species, spread of pathogens and climate change. Recently, the rapid global increase in artificial light at night has been proposed to be a new threat to terrestrial ecosystems; the consequences of this increase for ecosystem function are mostly unknown. Here we show that artificial light at night disrupts nocturnal pollination networks and has negative consequences for plant reproductive success. In artificially illuminated plant-pollinator communities, nocturnal visits to plants were reduced by 62% compared to dark areas. Notably, this resulted in an overall 13% reduction in fruit set of a focal plant even though the plant also received numerous visits by diurnal pollinators. Furthermore, by merging diurnal and nocturnal pollination sub-networks, we show that the structure of these combined networks tends to facilitate the spread of the negative consequences of disrupted nocturnal pollination to daytime pollinator communities. Our findings demonstrate that artificial light at night is a threat to pollination and that the negative effects of artificial light at night on nocturnal pollination are predicted to propagate to the diurnal community, thereby aggravating the decline of the diurnal community. We provide perspectives on the functioning of plant-pollinator communities, showing that nocturnal pollinators are not redundant to diurnal communities and increasing our understanding of the human-induced decline in pollinators and their ecosystem service.

  5. Forest remnants enhance wild pollinator visits to cashew flowers and mitigate pollination deficit in NE Brazil

    Directory of Open Access Journals (Sweden)

    Breno Magalhães Freitas

    2014-02-01

    Full Text Available Pollination deficit could cause low yields in cashew (Anacardium occidentale and it is possible that deforestation surrounding cashew plantations may prevent effective pollinators from visiting cashew flowers and contribute to this deficit. In the present work, we investigated the proximity effect of small and large forest fragments on the abundance and flower visits by feral Apis mellifera and wild native pollinators to cashew flowers and their interactions with yield in cashew plantations. Cashew nut yield was highest when plantations bordered a small forest fragment and were close to the large forest fragment. Yield from plantations that did not border small forest fragments but were close to the large forest fragment did not differ to yield from plantations at a greater distance to the large forest fragment. Flower visits by wild native pollinators, mainly Trigona spinipes, were negatively affected by distance to the large forest remnant and their numbers were directly correlated to nut yield. The number of A. mellifera visiting cashew flowers did not change significantly with distance to forest fragments, nor was it correlated with yield. We conclude that increasing the number of wild pollinator visits may increase yield, and proximity to large forest fragments are important for this.

  6. Wind energy information guide

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-04-01

    This book is divided into nine chapters. Chapters 1--8 provide background and annotated references on wind energy research, development, and commercialization. Chapter 9 lists additional sources of printed information and relevant organizations. Four indices provide alphabetical access to authors, organizations, computer models and design tools, and subjects. A list of abbreviations and acronyms is also included. Chapter topics include: introduction; economics of using wind energy; wind energy resources; wind turbine design, development, and testing; applications; environmental issues of wind power; institutional issues; and wind energy systems development.

  7. Bats and bees are pollinating Parkia biglobosa in the Gambia

    DEFF Research Database (Denmark)

    Lassen, Kristin Marie; Ræbild, Anders; Hansen, Henrik

    2012-01-01

    A pollination experiment was conducted with Parkia biglobosa (Fabaceae) in The Gambia. P. biglobosa is integrated in the farming systems and produces fruit pulp and seeds used in cooking. The species is bat-pollinated, and in areas with few bats the main pollinators are assumed to be honey bees...... as replicates. The pollinators’ identity, efficiency, and relative effect were determined. Bats, honey bees, and stingless bees were able to pollinate the species. Bat-visited capitula produced more pods, but not significantly more than honey bees. Honey bees were more efficient than stingless bees, resulting...... was analysed and a positive correlation between number of seeds per pod and the sugar content was found. Improved pollination success may thus result in sweeter fruits. We conclude it is important to strive against a pollinator-friendly environment in order to attract bats and bees. Furthermore, we suggest...

  8. Apis mellifera pollination improves agronomic productivity of anemophilous castor bean (Ricinus communis

    Directory of Open Access Journals (Sweden)

    Rômulo A.G. Rizzardo

    2012-12-01

    Full Text Available Castor bean (Ricinus communis L. is cultivated mainly for biodiesel production because of its oil-rich seeds; it is assumed to be an anemophylous species. But pollination deficit can lead to low productivity often attributed to other reasons. In this paper, we investigated pollination requirements, pollination mechanism, occurrence of pollination deficit, and the role of biotic pollinators in a large commercial plantation of castor bean. Our results show that R. communis bears a mixed breeding system favoring selfing by geitonogamy, although the wind promotes mostly outcrossing. We also found that the honey bee (Apis mellifera L. foraging on castor bean can both transfer pollen from male to female flowers within the same raceme and boost the release of airborne pollen by male flowers. Both situations increase geitonogamy rates, raising significantly fruit set and seed yield. This is the first report of an animal foraging activity increasing seed yield in an anemophilous and geitonogamous crop and elucidates the role of biotic pollinators in castor bean reproduction.A mamoneira (Ricinus communis L. é cultivada principalmente para produção de biodiesel devido ao alto teor de óleo de suas sementes e considerada como sendo de polinização anemófila. Mas déficits de polinização podem levar a baixos índices de produtividade geralmente atribuídos a outros fatores. Neste trabalho foram investigados os requerimentos, mecanismos e déficit de polinização e o papel dos polinizadores bióticos em um monocultivo comercial de mamona. Os resultados mostram que R. communis possui um sistema de polinização misto, favorecendo a autopolinização por geitonogamia, embora o vento normalmente promova polinização cruzada. Observou-se também que a abelha melífera (Apis mellifera L. forrageando na mamoneira pode tanto transferir pólen das flores estaminadas para as pistiladas do mesmo racemo, quanto aumentar consideravelmente a liberação de p

  9. Physico-Chemical Characteristics of Pollinated and Non Pollinated Date Fruit of District Khairpur, Sindh, Pakistan

    Directory of Open Access Journals (Sweden)

    Wahid Bux Jatoi

    2012-12-01

    Full Text Available Elemental patterns are often used for the classification or identification of date fruit varieties. Five ripening stages of six date varieties were collected and studied from the pre ripening to the post ripening stage. Pollinated and non-pollinated date fruit of the same varieties were compared for their physical and chemical parameters. Physical parameters such as size, mass, colour, moisture, and pH were measured. In case of chemical characteristics the mineral composition of six different varieties of district Khairpur dates palm (Phoenix dactylifera L. fruit (Gorho, Asul Khurmo, Nur Aseel, Ghuray Wari, Toto, and Allah Wari were analysed using Atomic Absorption Spectroscopy (AAS. Generally, size, moisture and mineral content of the pollinated fruit increased up to 3rd and 4th stage then declined.

  10. Nectar properties and the role of sunbirds as pollinators of the golden-flowered tea (Camellia petelotii).

    Science.gov (United States)

    Sun, Shi-Guo; Huang, Zhi-Huan; Chen, Zhi-Bao; Huang, Shuang-Quan

    2017-03-01

    Properties of floral nectar have been used to predict if a plant species is pollinated by birds. To see whether winter-flowering plants evolve nectar properties corresponding to bird pollinators, nectar properties of several Camellia species (including the golden-flowered tea), as well as the role of floral visitors as effective pollinators, were examined. Potential pollinators of Camellia petelotii were identified at different times of day and under various weather conditions. A bird exclusion experiment was used to compare the pollination effectiveness of birds and insects. Nectar sugar components (fructose, glucose, and sucrose) from C. petelotii growing wild and another seven Camellia species and 22 additional cultivars (all in cultivation) were examined by high-performance liquid chromatography (HPLC). The sunbird Aethopyga siparaja and honeybees were the most frequent floral visitors to C. petelotii . Honeybee visits were significantly reduced in cloudy/rainy weather. The fruit and seed set of flowers with birds excluded were reduced by 64%, indicating that bird pollination is significant. For the wild populations of C. petelotii , a bagged flower could secrete 157 μL nectar; this nectar has a low sugar concentration (19%) and is sucrose-dominant (87%). The eight Camellia species and 22 cultivars had an average sugar concentration of around 30% and a sucrose concentration of 80%, demonstrating sucrose-dominant nectar in Camellia species. The nectar sugar composition of Camellia species was characterized by sucrose dominance. In addition, the large reduction in seed set when birds are excluded in the golden-flowered tea also supports the suggestion that these winter-flowering plants may have evolved with birds as significant pollinators. © 2017 Botanical Society of America.

  11. Has Pollination Mode Shaped the Evolution of Ficus Pollen?

    Science.gov (United States)

    Wang, Gang; Chen, Jin; Li, Zong-Bo; Zhang, Feng-Ping; Yang, Da-Rong

    2014-01-01

    Background The extent to which co-evolutionary processes shape morphological traits is one of the most fascinating topics in evolutionary biology. Both passive and active pollination modes coexist in the fig tree (Ficus, Moraceae) and fig wasp (Agaonidae, Hymenoptera) mutualism. This classic obligate relationship that is about 75 million years old provides an ideal system to consider the role of pollination mode shifts on pollen evolution. Methods and Main Findings Twenty-five fig species, which cover all six Ficus subgenera, and are native to the Xishuangbanna region of southwest China, were used to investigate pollen morphology with scanning electron microscope (SEM). Pollination mode was identified by the Anther/Ovule ratio in each species. Phylogenetic free regression and a correlated evolution test between binary traits were conducted based on a strong phylogenetic tree. Seventeen of the 25 fig species were actively pollinated and eight species were passively pollinated. Three pollen shape types and three kinds of exine ornamentation were recognized among these species. Pollen grains with ellipsoid shape and rugulate ornamentation were dominant. Ellipsoid pollen occurred in all 17 species of actively pollinated figs, while for the passively pollinated species, two obtuse end shapes were identified: cylinder and sphere shapes were identified in six of the eight species. All passively pollinated figs presented rugulate ornamentation, while for actively pollinated species, the smoother types - psilate and granulate-rugulate ornamentations - accounted for just five and two among the 17 species, respectively. The relationship between pollen shape and pollination mode was shown by both the phylogenetic free regression and the correlated evolution tests. Conclusions Three pollen shape and ornamentation types were found in Ficus, which show characteristics related to passive or active pollination mode. Thus, the pollen shape is very likely shaped by pollination mode

  12. Floral adaptation to local pollinator guilds in a terrestrial orchid.

    Science.gov (United States)

    Sun, Mimi; Gross, Karin; Schiestl, Florian P

    2014-01-01

    Studies of local floral adaptation in response to geographically divergent pollinators are essential for understanding floral evolution. This study investigated local pollinator adaptation and variation in floral traits in the rewarding orchid Gymnadenia odoratissima, which spans a large altitudinal gradient and thus may depend on different pollinator guilds along this gradient. Pollinator communities were assessed and reciprocal transfer experiments were performed between lowland and mountain populations. Differences in floral traits were characterized by measuring floral morphology traits, scent composition, colour and nectar sugar content in lowland and mountain populations. The composition of pollinator communities differed considerably between lowland and mountain populations; flies were only found as pollinators in mountain populations. The reciprocal transfer experiments showed that when lowland plants were transferred to mountain habitats, their reproductive success did not change significantly. However, when mountain plants were moved to the lowlands, their reproductive success decreased significantly. Transfers between populations of the same altitude did not lead to significant changes in reproductive success, disproving the potential for population-specific adaptations. Flower size of lowland plants was greater than for mountain flowers. Lowland plants also had significantly higher relative amounts of aromatic floral volatiles, while the mountain plants had higher relative amounts of other floral volatiles. The floral colour of mountain flowers was significantly lighter compared with the lowland flowers. Local pollinator adaptation through pollinator attraction was shown in the mountain populations, possibly due to adaptation to pollinating flies. The mountain plants were also observed to receive pollination from a greater diversity of pollinators than the lowland plants. The different floral phenotypes of the altitudinal regions are likely to be the

  13. Floral scent and pollinators of the holoparasite Pilostyles thurberi (Apodanthaceae)

    OpenAIRE

    Sedonia D Sipes; Kara E. Huff Hartz; Hardik Amin; Daniel L. Nickrent

    2014-01-01

    Floral scent is likely important to the pollination of parasitic plants, despite that it has not been well-studied. We studied the pollination ecology of the North American stem holoparasite Pilostyles thurberi (Apodanthaceae) at two field sites in Texas. To identify effective pollinators, we collected floral visitors to P. thurberi flowers, observed their foraging behavior, and looked for P. thurberi pollen on their bodies. Augochloropsis metallica bees (Halictidae) and eumenine potter wasps...

  14. Ecosystem restoration strengthens pollination network resilience and function.

    Science.gov (United States)

    Kaiser-Bunbury, Christopher N; Mougal, James; Whittington, Andrew E; Valentin, Terence; Gabriel, Ronny; Olesen, Jens M; Blüthgen, Nico

    2017-02-09

    Land degradation results in declining biodiversity and the disruption of ecosystem functioning worldwide, particularly in the tropics. Vegetation restoration is a common tool used to mitigate these impacts and increasingly aims to restore ecosystem functions rather than species diversity. However, evidence from community experiments on the effect of restoration practices on ecosystem functions is scarce. Pollination is an important ecosystem function and the global decline in pollinators attenuates the resistance of natural areas and agro-environments to disturbances. Thus, the ability of pollination functions to resist or recover from disturbance (that is, the functional resilience) may be critical for ensuring a successful restoration process. Here we report the use of a community field experiment to investigate the effects of vegetation restoration, specifically the removal of exotic shrubs, on pollination. We analyse 64 plant-pollinator networks and the reproductive performance of the ten most abundant plant species across four restored and four unrestored, disturbed mountaintop communities. Ecosystem restoration resulted in a marked increase in pollinator species, visits to flowers and interaction diversity. Interactions in restored networks were more generalized than in unrestored networks, indicating a higher functional redundancy in restored communities. Shifts in interaction patterns had direct and positive effects on pollination, especially on the relative and total fruit production of native plants. Pollinator limitation was prevalent at unrestored sites only, where the proportion of flowers producing fruit increased with pollinator visitation, approaching the higher levels seen in restored plant communities. Our results show that vegetation restoration can improve pollination, suggesting that the degradation of ecosystem functions is at least partially reversible. The degree of recovery may depend on the state of degradation before restoration

  15. A global test of the pollination syndrome hypothesis.

    Science.gov (United States)

    Ollerton, Jeff; Alarcón, Ruben; Waser, Nickolas M; Price, Mary V; Watts, Stella; Cranmer, Louise; Hingston, Andrew; Peter, Craig I; Rotenberry, John

    2009-06-01

    'Pollination syndromes' are suites of phenotypic traits hypothesized to reflect convergent adaptations of flowers for pollination by specific types of animals. They were first developed in the 1870s and honed during the mid 20th Century. In spite of this long history and their central role in organizing research on plant-pollinator interactions, the pollination syndromes have rarely been subjected to test. The syndromes were tested here by asking whether they successfully capture patterns of covariance of floral traits and predict the most common pollinators of flowers. Flowers in six communities from three continents were scored for expression of floral traits used in published descriptions of the pollination syndromes, and simultaneously the pollinators of as many species as possible were characterized. Ordination of flowers in a multivariate 'phenotype space' defined by the syndromes showed that almost no plant species fall within the discrete syndrome clusters. Furthermore, in approximately two-thirds of plant species, the most common pollinator could not be successfully predicted by assuming that each plant species belongs to the syndrome closest to it in phenotype space. The pollination syndrome hypothesis as usually articulated does not successfully describe the diversity of floral phenotypes or predict the pollinators of most plant species. Caution is suggested when using pollination syndromes for organizing floral diversity, or for inferring agents of floral adaptation. A fresh look at how traits of flowers and pollinators relate to visitation and pollen transfer is recommended, in order to determine whether axes can be identified that describe floral functional diversity more successfully than the traditional syndromes.

  16. Wind energy

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    This chapter discusses the role wind energy may have in the energy future of the US. The topics discussed in the chapter include historical aspects of wind energy use, the wind energy resource, wind energy technology including intermediate-size and small wind turbines and intermittency of wind power, public attitudes toward wind power, and environmental, siting and land use issues

  17. Embryological studies on Fragaria x ananassa Duch. after pollination by three species of Potentilla

    Directory of Open Access Journals (Sweden)

    Katarzyna Niemirowicz-Szczytt

    2014-01-01

    Full Text Available Embryological studies were carried out after pollinating four female varieties of Fragaria ananassa Duch. (Freja, Sonja, Mieze Schindler, Reine des Precoce with three species of Poteiatilla (P. geoides, P. rupestris, P. fruticosa. The aim was to elucidate the manner in which matroclinous progeny arises after pollination of the strawberry with Potentilla pollen. In addition to meiotic, apo- and diplosporous embryo sacs were formed in the Freja variety. On the average, in the four studied varieties,, 49% of the ovules contained more than one embryo sac. At the most, five embryo sacs developed, but only two of them attained full maturity. Pollen from Potentilla germinated on the stigma of the strawberry and the pollen tubes grew through the style to the ovule. Symptoms of fertilization were not found in the strawberry ovules after pollination with Potentilla, however, after pollination with the Redgauntlet F. x ananassa variety, extra nucleoli or chromatin grains were found in the ovule. False polyembryony was found in the Mieze Schindler (16 cases, Sonja (2 cases and Freja (1 case varieties. The germination of two plants from one seed was observed, which shows the possibility of full development of twin embryos. The low germination ability of the seeds was caused by abnormalities in the development of the embryos.

  18. Traits and phylogenetic history contribute to network structure across Canadian plant-pollinator communities.

    Science.gov (United States)

    Chamberlain, Scott A; Cartar, Ralph V; Worley, Anne C; Semmler, Sarah J; Gielens, Grahame; Elwell, Sherri; Evans, Megan E; Vamosi, Jana C; Elle, Elizabeth

    2014-10-01

    Interaction webs, or networks, define how the members of two or more trophic levels interact. However, the traits that mediate network structure have not been widely investigated. Generally, the mechanism that determines plant-pollinator partnerships is thought to involve the matching of a suite of species traits (such as abundance, phenology, morphology) between trophic levels. These traits are often unknown or hard to measure, but may reflect phylogenetic history. We asked whether morphological traits or phylogenetic history were more important in mediating network structure in mutualistic plant-pollinator interaction networks from Western Canada. At the plant species level, sexual system, growth form, and flower symmetry were the most important traits. For example species with radially symmetrical flowers had more connections within their modules (a subset of species that interact more among one another than outside of the module) than species with bilaterally symmetrical flowers. At the pollinator species level, social species had more connections within and among modules. In addition, larger pollinators tended to be more specialized. As traits mediate interactions and have a phylogenetic signal, we found that phylogenetically close species tend to interact with a similar set of species. At the network level, patterns were weak, but we found increasing functional trait and phylogenetic diversity of plants associated with increased weighted nestedness. These results provide evidence that both specific traits and phylogenetic history can contribute to the nature of mutualistic interactions within networks, but they explain less variation between networks.

  19. Pollinator diversity affects plant reproduction and recruitment: the tradeoffs of generalization.

    Science.gov (United States)

    Gómez, José M; Bosch, Jordi; Perfectti, Francisco; Fernández, Juande; Abdelaziz, Mohamed

    2007-09-01

    One outstanding and unsolved challenge in ecology and conservation biology is to understand how pollinator diversity affects plant performance. Here, we provide evidence of the functional role of pollination diversity in a plant species, Erysimum mediohispanicum (Brassicaceae). Pollinator abundance, richness and diversity as well as plant reproduction and recruitment were determined in eight plant populations. We found that E. mediohispanicum was generalized both at the regional and local (population) scale, since its flowers were visited by more than 100 species of insects with very different morphology, size and behaviour. However, populations differed in the degree of generalization. Generalization correlated with pollinator abundance and plant population size, but not with habitat, ungulate damage intensity, altitude or spatial location. More importantly, the degree of generalization had significant consequences for plant reproduction and recruitment. Plants from populations with intermediate generalization produced more seeds than plants from populations with low or high degrees of generalization. These differences were not the result of differences in number of flowers produced per plant. In addition, seedling emergence in a common garden was highest in plants from populations with intermediate degree of generalization. This outcome suggests the existence of an optimal level of generalizations even for generalized plant species.

  20. Adaptive foraging behaviour of individual pollinators and the coexistence of co-flowering plants

    Science.gov (United States)

    Song, Zhiyuan; Feldman, Marcus W.

    2014-01-01

    Although pollinators can play a central role in determining the structure and stability of plant communities, little is known about how their adaptive foraging behaviours at the individual level, e.g. flower constancy, structure these interactions. Here, we construct a mathematical model that integrates individual adaptive foraging behaviour and population dynamics of a community consisting of two plant species and a pollinator species. We find that adaptive foraging at the individual level, as a complementary mechanism to adaptive foraging at the species level, can further enhance the coexistence of plant species through niche partitioning between conspecific pollinators. The stabilizing effect is stronger than that of unbiased generalists when there is also strong competition between plant species over other resources, but less so than that of multiple specialist species. This suggests that adaptive foraging in mutualistic interactions can have a very different impact on the plant community structure from that in predator–prey interactions. In addition, the adaptive behaviour of individual pollinators may cause a sharp regime shift for invading plant species. These results indicate the importance of integrating individual adaptive behaviour and population dynamics for the conservation of native plant communities. PMID:24352943

  1. Degradation of soil fertility can cancel pollination benefits in sunflower.

    Science.gov (United States)

    Tamburini, Giovanni; Berti, Antonio; Morari, Francesco; Marini, Lorenzo

    2016-02-01

    Pollination and soil fertility are important ecosystem services to agriculture but their relative roles and potential interactions are poorly understood. We explored the combined effects of pollination and soil fertility in sunflower using soils from a trial characterized by different long-term input management in order to recreate plausible levels of soil fertility. Pollinator exclusion was used as a proxy for a highly eroded pollination service. Pollination benefits to yield depended on soil fertility, i.e., insect pollination enhanced seed set and yield only under higher soil fertility indicating that limited nutrient availability may constrain pollination benefits. Our study provides evidence for interactions between above- and belowground ecosystem services, highlighting the crucial role of soil fertility in supporting agricultural production not only directly, but also indirectly through pollination. Management strategies aimed at enhancing pollination services might fail in increasing yield in landscapes characterized by high soil service degradation. Comprehensive knowledge about service interactions is therefore essential for the correct management of ecosystem services in agricultural landscapes.

  2. Pollination, biogeography and phylogeny of oceanic island bellflowers (Campanulaceae)

    DEFF Research Database (Denmark)

    Olesen, Jens Mogens; Alarcón, M.; Ehlers, Bodil

    2012-01-01

    relatives C. eminii and C. abyssinica. We asked to what extent related species converge in their floral biology and pollination in related habitats, i.e. oceanic islands. Study islands were the Azores, Madeira, Canary Islands, Cape Verde, Mauritius, and Réunion. Information about phylogenetic relationships....... These examples of vertebrate pollination evolved independently on each island or archipelago. We discuss if these pollination systems have an island or mainland origin and when they may have evolved, and finally, we attempt to reconstruct the pollinator-interaction history of each species....

  3. Pollination benefits are maximized at intermediate nutrient levels.

    Science.gov (United States)

    Tamburini, Giovanni; Lami, Francesco; Marini, Lorenzo

    2017-08-16

    Yield production in flowering crops depends on both nutrient availability and pollination, but their relative roles and potential interactions are poorly understood. We measured pollination benefits to yield in sunflower, combining a gradient in insect pollination (0, 25, 50, 100%) with a continuous gradient in nitrogen (N) fertilization (from 0 to 150 kg N ha -1 ) in an experiment under realistic soil field conditions. We found that pollination benefits to yield were maximized at intermediate levels of N availability, bolstering yield by approximately 25% compared with complete pollinator exclusion. Interestingly, we found little decrease in yield when insect visits were reduced by 50%, indicating that the incremental contribution of pollination by insects to yield is greater when the baseline pollination service provision is very low. Our findings provide strong evidence for interactive, nonlinear effects of pollination and resource availability on seed production. Our results support ecological intensification as a promising strategy for sustainable management of agroecosystems. In particular, we found optimal level of pollination to potentially compensate for lower N applications. © 2017 The Author(s).

  4. Breeding system and pollination biology of the semidomesticated ...

    African Journals Online (AJOL)

    Breeding system and pollination biology of the semidomesticated fruit tree, Tamarindus indica L. (Leguminosae: Caesalpinioideae ): Implications for fruit production, selective breeding, and conservation of genetic resources.

  5. How shrub encroachment under climate change could threaten pollination services for alpine wildflowers: A case study using the alpine skypilot,Polemonium viscosum.

    Science.gov (United States)

    Kettenbach, Jessica A; Miller-Struttmann, Nicole; Moffett, Zoë; Galen, Candace

    2017-09-01

    Under climate change, shrubs encroaching into high altitude plant communities disrupt ecosystem processes. Yet effects of encroachment on pollination mutualisms are poorly understood. Here, we probe potential fitness impacts of interference from encroaching Salix (willows) on pollination quality of the alpine skypilot, Polemonium viscosum . Overlap in flowering time of Salix and Polemonium is a precondition for interference and was surveyed in four extant and 25 historic contact zones. Pollinator sharing was ascertained from observations of willow pollen on bumble bees visiting Polemonium flowers and on Polemonium pistils. We probed fitness effects of pollinator sharing by measuring the correlation between Salix pollen contamination and seed set in naturally pollinated Polemonium . To ascertain whether Salix interference occurred during or after pollination, we compared seed set under natural pollination, conspecific pollen addition, and Salix pollen addition. In current and past contact zones Polemonium and Salix overlapped in flowering time. After accounting for variance in flowering date due to latitude, Salix and Polemonium showed similar advances in flowering under warmer summers. This trend supports the idea that sensitivity to temperature promotes reproductive synchrony in both species. Salix pollen is carried by bumble bees when visiting Polemonium flowers and accounts for up to 25% of the grains on Polemonium pistils. Salix contamination correlates with reduced seed set in nature and when applied experimentally. Postpollination processes likely mediate these deleterious effects as seed set in nature was not limited by pollen delivery. As willows move higher with climate change, we predict that they will drive postpollination interference, reducing the fitness benefits of pollinator visitation for Polemonium and selecting for traits that reduce pollinator sharing.

  6. Functional Diversity of Plant–Pollinator Interaction Webs Enhances the Persistence of Plant Communities

    Science.gov (United States)

    Dajoz, Isabelle; Meriguet, Jacques; Loreau, Michel

    2006-01-01

    Pollination is exclusively or mainly animal mediated for 70% to 90% of angiosperm species. Thus, pollinators provide an essential ecosystem service to humankind. However, the impact of human-induced biodiversity loss on the functioning of plant–pollinator interactions has not been tested experimentally. To understand how plant communities respond to diversity changes in their pollinating fauna, we manipulated the functional diversity of both plants and pollinators under natural conditions. Increasing the functional diversity of both plants and pollinators led to the recruitment of more diverse plant communities. After two years the plant communities pollinated by the most functionally diverse pollinator assemblage contained about 50% more plant species than did plant communities pollinated by less-diverse pollinator assemblages. Moreover, the positive effect of functional diversity was explained by a complementarity between functional groups of pollinators and plants. Thus, the functional diversity of pollination networks may be critical to ecosystem sustainability. PMID:16332160

  7. Functional diversity of plant-pollinator interaction webs enhances the persistence of plant communities.

    Science.gov (United States)

    Fontaine, Colin; Dajoz, Isabelle; Meriguet, Jacques; Loreau, Michel

    2006-01-01

    Pollination is exclusively or mainly animal mediated for 70% to 90% of angiosperm species. Thus, pollinators provide an essential ecosystem service to humankind. However, the impact of human-induced biodiversity loss on the functioning of plant-pollinator interactions has not been tested experimentally. To understand how plant communities respond to diversity changes in their pollinating fauna, we manipulated the functional diversity of both plants and pollinators under natural conditions. Increasing the functional diversity of both plants and pollinators led to the recruitment of more diverse plant communities. After two years the plant communities pollinated by the most functionally diverse pollinator assemblage contained about 50% more plant species than did plant communities pollinated by less-diverse pollinator assemblages. Moreover, the positive effect of functional diversity was explained by a complementarity between functional groups of pollinators and plants. Thus, the functional diversity of pollination networks may be critical to ecosystem sustainability.

  8. Functional Diversity of Plant-Pollinator Interaction Webs Enhances the Persistence of Plant Communities.

    Directory of Open Access Journals (Sweden)

    2005-12-01

    Full Text Available Pollination is exclusively or mainly animal mediated for 70% to 90% of angiosperm species. Thus, pollinators provide an essential ecosystem service to humankind. However, the impact of human-induced biodiversity loss on the functioning of plant-pollinator interactions has not been tested experimentally. To understand how plant communities respond to diversity changes in their pollinating fauna, we manipulated the functional diversity of both plants and pollinators under natural conditions. Increasing the functional diversity of both plants and pollinators led to the recruitment of more diverse plant communities. After two years the plant communities pollinated by the most functionally diverse pollinator assemblage contained about 50% more plant species than did plant communities pollinated by less-diverse pollinator assemblages. Moreover, the positive effect of functional diversity was explained by a complementarity between functional groups of pollinators and plants. Thus, the functional diversity of pollination networks may be critical to ecosystem sustainability.

  9. Functional diversity of plant-pollinator interaction webs enhances the persistence of plant communities.

    Directory of Open Access Journals (Sweden)

    Colin Fontaine

    2006-01-01

    Full Text Available Pollination is exclusively or mainly animal mediated for 70% to 90% of angiosperm species. Thus, pollinators provide an essential ecosystem service to humankind. However, the impact of human-induced biodiversity loss on the functioning of plant-pollinator interactions has not been tested experimentally. To understand how plant communities respond to diversity changes in their pollinating fauna, we manipulated the functional diversity of both plants and pollinators under natural conditions. Increasing the functional diversity of both plants and pollinators led to the recruitment of more diverse plant communities. After two years the plant communities pollinated by the most functionally diverse pollinator assemblage contained about 50% more plant species than did plant communities pollinated by less-diverse pollinator assemblages. Moreover, the positive effect of functional diversity was explained by a complementarity between functional groups of pollinators and plants. Thus, the functional diversity of pollination networks may be critical to ecosystem sustainability.

  10. Pollinator guilds respond differently to urban habitat fragmentation in a oak-savannah ecosystem

    Science.gov (United States)

    Habitat fragmentation is widely thought to threaten biodiversity. However, response of pollinators to habitat fragmentation is still poorly understood, as pollinator communities are notoriously spatially variable. We investigated pollinator community structure in a highly fragmented oak-savannah ec...

  11. Synergistic effects of non-Apis bees and honey bees for pollination services.

    OpenAIRE

    Brittain, C; Williams, N; Kremen, C; Klein, AM

    2013-01-01

    In diverse pollinator communities, interspecific interactions may modify the behaviour and increase the pollination effectiveness of individual species. Because agricultural production reliant on pollination is growing, improving pollination effectiveness could increase crop yield without any increase in agricultural intensity or area. In California almond, a crop highly dependent on honey bee pollination, we explored the foraging behaviour and pollination effectiveness of honey bees in orcha...

  12. Sexual dimorphism of staminate- and pistillate-phase flowers of Saponaria officinalis (bouncing bet) affects pollinator behavior and seed set.

    Science.gov (United States)

    Davis, Sandra L; Dudle, Dana A; Nawrocki, Jenna R; Freestone, Leah M; Konieczny, Peter; Tobin, Michael B; Britton, Michael M

    2014-01-01

    The sequential separation of male and female function in flowers of dichogamous species allows for the evolution of differing morphologies that maximize fitness through seed siring and seed set. We examined staminate- and pistillate-phase flowers of protandrous Saponaria officinalis for dimorphism in floral traits and their effects on pollinator attraction and seed set. Pistillate-phase flowers have larger petals, greater mass, and are pinker in color, but due to a shape change, pistillate-phase flowers have smaller corolla diameters than staminate-phase flowers. There was no difference in nectar volume or sugar content one day after anthesis, and minimal evidence for UV nectar guide patterns in staminate- and pistillate-phase flowers. When presented with choice arrays, pollinators discriminated against pistillate-phase flowers based on their pink color. Finally, in an experimental garden, in 2012 there was a negative correlation between seed set of an open-pollinated, emasculated flower and pinkness (as measured by reflectance spectrometry) of a pistillate-phase flower on the same plant in plots covered with shade cloth. In 2013, clones of genotypes chosen from the 2012 plants that produced pinker flowers had lower seed set than those from genotypes with paler flowers. Lower seed set of pink genotypes was found in open-pollinated and hand-pollinated flowers, indicating the lower seed set might be due to other differences between pink and pale genotypes in addition to pollinator discrimination against pink flowers. In conclusion, staminate- and pistillate-phase flowers of S. officinalis are dimorphic in shape and color. Pollinators discriminate among flowers based on these differences, and individuals whose pistillate-phase flowers are most different in color from their staminate-phase flowers make fewer seeds. We suggest morphological studies of the two sex phases in dichogamous, hermaphroditic species can contribute to understanding the evolution of sexual

  13. A specialized bird pollination system with a bellows mechanism for pollen transfer and staminal food body rewards.

    Science.gov (United States)

    Dellinger, Agnes S; Penneys, Darin S; Staedler, Yannick M; Fragner, Lena; Weckwerth, Wolfram; Schönenberger, Jürg

    2014-07-21

    Bird pollination has evolved repeatedly among flowering plants but is almost exclusively characterized by passive transfer of pollen onto the bird and by nectar as primary reward [1, 2]. Food body rewards are exceedingly rare among eudicot flowering plants and are only known to occur on sterile floral organs [3]. In this study, we report an alternative bird pollination mechanism involving bulbous stamen appendages in the Neotropical genus Axinaea (Melastomataceae). We studied the pollination process by combining pollination experiments, video monitoring, and detailed analyses of stamen structure and metabolomic composition. We show that the bulbous stamen appendages, which are consumed by various species of passerines (Thraupidae, Fringillidae), are bifunctional during the pollination process. First, the appendages work as bellows organs in a unique pollen expulsion mechanism activated by the passerines. As the birds seize an appendage with their beaks in order to remove it from the flower for consumption, air contained in the appendage's aerenchymatous tissue is pressed into the hollow anther. The resulting air flow causes the expulsion of a pollen jet and the deposition of pollen on the bird's head and beak. Second, the stamen appendages provide a hexose-rich, highly nutritious (15,100 J/g) food body reward for the pollinating passerines. This discovery expands our knowledge of flowering plant pollination systems and provides the first report of highly specialized bellows organs for active pollen transfer in flowering plants. In addition, this is the only known case of a food body reward associated with reproductive structures in the eudicot clade of flowering plants. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Protandry promotes male pollination success in a moth-pollinated orchid

    Czech Academy of Sciences Publication Activity Database

    Jersáková, Jana; Johnson, S.D.

    2007-01-01

    Roč. 21, č. 3 (2007), s. 496-504 ISSN 0269-8463 Institutional research plan: CEZ:AV0Z60870520 Keywords : dichogamy * geitonogamy * inbreeding * Orchidaceae * pollen discounting * self-pollination Subject RIV: EH - Ecology, Behaviour Impact factor: 3.157, year: 2007

  15. Generalization versus Specialization in Pollination Systems: Visitors, Thieves, and Pollinators of Hypoestes aristata (Acanthaceae)

    Czech Academy of Sciences Publication Activity Database

    Padyšáková, Eliška; Bartoš, Michael; Tropek, Robert; Janeček, Štěpán

    2013-01-01

    Roč. 8, č. 4 (2013), e59299 E-ISSN 1932-6203 R&D Projects: GA ČR(CZ) GAP505/11/1617 Institutional support: RVO:67985939 ; RVO:60077344 Keywords : generalization * specialization * pollinators Subject RIV: EH - Ecology, Behaviour Impact factor: 3.534, year: 2013

  16. Integrated crop pollination: Combining strategies to ensure stable and sustainable yields of pollination-dependent crops

    Science.gov (United States)

    Meeting the nutritional needs of our growing human population will be increasingly dependent on bees and other pollinators that provide the essential delivery of pollen to crop flowers during bloom. Honey bees have experienced population declines in some regions, and similar changes are evident for ...

  17. Pollination syndromes ignored: importance of non-ornithophilous flowers to Neotropical savanna hummingbirds

    Science.gov (United States)

    Maruyama, Pietro K.; Oliveira, Genilda M.; Ferreira, Carolina; Dalsgaard, Bo; Oliveira, Paulo E.

    2013-11-01

    Generalization prevails in flower-animal interactions, and although animal visitors are not equally effective pollinators, most interactions likely represent an important energy intake for the animal visitor. Hummingbirds are nectar-feeding specialists, and many tropical plants are specialized toward hummingbird-pollination. In spite of this, especially in dry and seasonal tropical habitats, hummingbirds may often rely on non-ornithophilous plants to meet their energy requirements. However, quantitative studies evaluating the relative importance of ornithophilous vs. non-ornithophilous plants for hummingbirds in these areas are scarce. We here studied the availability and use of floral resources by hummingbirds in two different areas of the Cerrado, the seasonal savannas in Central Brazil. Roughly half the hummingbird visited plant species were non-ornithophilous, and these contributed greatly to increase the overall nectar availability. We showed that mean nectar offer, at the transect scale, was the only parameter related to hummingbird visitation frequency, more so than nectar offer at single flowers and at the plant scale, or pollination syndrome. Centrality indices, calculated using hummingbird-plant networks, showed that ornithophilous and non-ornithophilous plants have similar importance for network cohesion. How this foraging behaviour affects reproduction of non-ornithophilous plants remains largely unexplored and is probably case specific, however, we suggest that the additional energy provided by non-ornithophilous plants may facilitate reproduction of truly ornithophilous flowers by attracting and maintaining hummingbirds in the area. This may promote asymmetric hummingbird-plant associations, i.e., pollination depends on floral traits adapted to hummingbird morphology, but hummingbird visitation is determined more by the energetic "reward" than by pollination syndromes.

  18. Managed Bumble Bees (Bombus impatiens) (Hymenoptera: Apidae) Caged With Blueberry Bushes at High Density Did Not Increase Fruit Set or Fruit Weight Compared to Open Pollination.

    Science.gov (United States)

    Campbell, J W; O'Brien, J; Irvin, J H; Kimmel, C B; Daniels, J C; Ellis, J D

    2017-04-01

    Highbush blueberry (Vaccinium corymbosum L.) is an important crop grown throughout Florida. Currently, most blueberry growers use honey bees (Apis mellifera L.) to provide pollination services for highbush blueberries even though bumble bees (Bombus spp.) have been shown to be more efficient at pollinating blueberries on a per bee basis. In general, contribution of bumble bees to the pollination of commercial highbush blueberries in Florida is unknown. Herein, we determined if managed bumble bees could contribute to highbush blueberry pollination. There were four treatments in this study: two treatments of caged commercial bumble bee (Bombus impatiens Cresson) colonies (low and high weight hives), a treatment excluding all pollinators, and a final treatment which allowed all pollinators (managed and wild pollinators) in the area have access to the plot. All treatments were located within a highbush blueberry field containing two cultivars of blooming plants, 'Emerald' and 'Millennia', with each cage containing 16 mature blueberry plants. We gathered data on fruit set, berry weight, and number of seeds produced per berry. When pollinators were excluded, fruit set was significantly lower in both cultivars (58%). Berry weight was not significantly different among the treatments, and the number of seeds per berry did not show a clear response. This study emphasizes the importance of bumble bees as an effective pollinator of blueberries and the potential beneficial implications of the addition of bumble bees in commercial blueberry greenhouses or high tunnels. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  19. Use of video surveillance to measure the influences of habitat management and landscape composition on pollinator visitation and pollen deposition in pumpkin (Cucurbita pepo agroecosystems

    Directory of Open Access Journals (Sweden)

    Benjamin W. Phillips

    2015-11-01

    Full Text Available Pumpkin (Cucurbita pepo production relies on insect-mediated pollination, which is provided by managed and wild pollinators. The goals of this study were to measure the visitation frequency, longevity and temporal activity patterns of pumpkin pollinators and to determine if local habitat management and landscape composition affected this pollination service. We used video surveillance to monitor bee acitivty within male and female pumpkin flowers in 2011 and 2012 across a pollination window of 0600–1200 h. We also quantified the amount of pollen deposited in female flowers across this time period. In 2011, A. mellifera made significantly more floral visits than other bees, and in 2012 Bombus spp. was the dominant pumpkin pollinator. We found variation in visitation among male and female pumpkin flowers, with A. mellifera visiting female flowers more often and spending longer per visit within them than male flowers in both 2011 and 2012. The squash bee P. pruinosa visited male flowers more frequently in 2012, but individuals spent equal time in both flower sexes. We did not find variation in the timing of flower visitation among species across the observed pollination window. In both 2011 and 2012 we found that the majority of pollen deposition occurred within the first two hours (0600–0800 h of observation; there was no difference between the pollen deposited during this two-hour period and full pollination window (0600–1200 h. Local additions of sweet alyssum floral strips or a field buffer strip of native wildflowers did not have an effect on the foraging activity of bees or pollen deposition. However, semi-natural and urban habitats in the surrounding landscape were positively correlated with the frequency of flower visitation by wild pollinators and the amount of pollen deposited within female flowers.

  20. Use of video surveillance to measure the influences of habitat management and landscape composition on pollinator visitation and pollen deposition in pumpkin (Cucurbita pepo) agroecosystems.

    Science.gov (United States)

    Phillips, Benjamin W; Gardiner, Mary M

    2015-01-01

    Pumpkin (Cucurbita pepo) production relies on insect-mediated pollination, which is provided by managed and wild pollinators. The goals of this study were to measure the visitation frequency, longevity and temporal activity patterns of pumpkin pollinators and to determine if local habitat management and landscape composition affected this pollination service. We used video surveillance to monitor bee acitivty within male and female pumpkin flowers in 2011 and 2012 across a pollination window of 0600-1200 h. We also quantified the amount of pollen deposited in female flowers across this time period. In 2011, A. mellifera made significantly more floral visits than other bees, and in 2012 Bombus spp. was the dominant pumpkin pollinator. We found variation in visitation among male and female pumpkin flowers, with A. mellifera visiting female flowers more often and spending longer per visit within them than male flowers in both 2011 and 2012. The squash bee P. pruinosa visited male flowers more frequently in 2012, but individuals spent equal time in both flower sexes. We did not find variation in the timing of flower visitation among species across the observed pollination window. In both 2011 and 2012 we found that the majority of pollen deposition occurred within the first two hours (0600-0800 h) of observation; there was no difference between the pollen deposited during this two-hour period and full pollination window (0600-1200 h). Local additions of sweet alyssum floral strips or a field buffer strip of native wildflowers did not have an effect on the foraging activity of bees or pollen deposition. However, semi-natural and urban habitats in the surrounding landscape were positively correlated with the frequency of flower visitation by wild pollinators and the amount of pollen deposited within female flowers.

  1. Use of video surveillance to measure the influences of habitat management and landscape composition on pollinator visitation and pollen deposition in pumpkin (Cucurbita pepo) agroecosystems

    Science.gov (United States)

    Phillips, Benjamin W.

    2015-01-01

    Pumpkin (Cucurbita pepo) production relies on insect-mediated pollination, which is provided by managed and wild pollinators. The goals of this study were to measure the visitation frequency, longevity and temporal activity patterns of pumpkin pollinators and to determine if local habitat management and landscape composition affected this pollination service. We used video surveillance to monitor bee acitivty within male and female pumpkin flowers in 2011 and 2012 across a pollination window of 0600–1200 h. We also quantified the amount of pollen deposited in female flowers across this time period. In 2011, A. mellifera made significantly more floral visits than other bees, and in 2012 Bombus spp. was the dominant pumpkin pollinator. We found variation in visitation among male and female pumpkin flowers, with A. mellifera visiting female flowers more often and spending longer per visit within them than male flowers in both 2011 and 2012. The squash bee P. pruinosa visited male flowers more frequently in 2012, but individuals spent equal time in both flower sexes. We did not find variation in the timing of flower visitation among species across the observed pollination window. In both 2011 and 2012 we found that the majority of pollen deposition occurred within the first two hours (0600–0800 h) of observation; there was no difference between the pollen deposited during this two-hour period and full pollination window (0600–1200 h). Local additions of sweet alyssum floral strips or a field buffer strip of native wildflowers did not have an effect on the foraging activity of bees or pollen deposition. However, semi-natural and urban habitats in the surrounding landscape were positively correlated with the frequency of flower visitation by wild pollinators and the amount of pollen deposited within female flowers. PMID:26587337

  2. Pollination in avocado flowers (Persea Americana Mill.)

    OpenAIRE

    Malerbo-Souza, Darclet Teresinha; Faculdade de Agronomia Dr. Francisco Maeda; Toledo, Vagner de Alencar Arnaut de; UEM; Silva, Simone Rodrigues da; Faculdade de Agronomia Dr. Francisco Maeda; Sousa, Francisco Fábio; Faculdade de Agronomia Dr. Francisco Maeda

    2008-01-01

    The experiment aimed to study the frequency, nectar and/or pollen and hoarding time of bees in avocado flowers and verify the effect of their visits on fruit production. Six inflorescences (three covered and three uncovered) with two replications were marked to evaluate the effect of cross pollination on fruition percentage. The honey bees showed two peaks of hoarding (by 11 to 12 a.m. and 5 p.m.) following the flowers opening of different avocado groups (groups A and B), as much for nectar a...

  3. Pollination and protection against herbivory of Nepalese Coelogyninae (Orchydaceae).

    NARCIS (Netherlands)

    Subedi, A.; Chaudhar, R.P.; Achterberg, C.; Heijerman, Th.; Lens, F.; Dooren, van T.J.M.; Gravendeel, B.

    2011-01-01

    • Premise of the Study: Although many species in the orchid genus Coelogyne are horticulturally popular, hardly anything is known about their pollination. Pollinators of three species were observed in the field in Nepal. This information is urgently needed because many orchid species in Nepal are

  4. Yucca aloifolia (Asparagaceae) opts out of an obligate pollination mutualism.

    Science.gov (United States)

    Rentsch, Jeremy D; Leebens-Mack, Jim

    2014-12-01

    • According to Cope's 'law of the unspecialized' highly dependent species interactions are 'evolutionary dead ends,' prone to extinction because reversion to more generalist interactions is thought to be unlikely. Cases of extreme specialization, such as those seen between obligate mutualists, are cast as evolutionarily inescapable, inevitably leading to extinction rather than diversification of participating species. The pollination mutualism between Yucca plants and yucca moths (Tegeticula and Parategeticula) would seem to be locked into such an obligate mutualism. Yucca aloifolia populations, however, can produce large numbers of fruit lacking moth oviposition scars. Here, we investigate the pollination ecology of Y. aloifolia, in search of the non-moth pollination of a Yucca species.• We perform pollinator exclusion studies on Yucca aloifolia and a sympatric yucca species, Y. filamentosa. We then perform postvisit exclusion treatments, an analysis of dissected fruits, and a fluorescent dye transfer experiment.• As expected, Yucca filamentosa plants set fruit only when inflorescences were exposed to crepuscular and nocturnal pollinating yucca moths. In contrast, good fruit set was observed when pollinators were excluded from Y. aloifolia inflorescences from dusk to dawn, and no fruit set was observed when pollinators were excluded during the day. Follow up experiments indicated that European honeybees (Apis mellifera) were passively yet effectively pollinating Y. aloifolia flowers.• These results indicate that even highly specialized mutualisms may not be entirely obligate interactions or evolutionary dead ends. © 2014 Botanical Society of America, Inc.

  5. Insect assemblage and the pollination system in cocoa ecosystems

    African Journals Online (AJOL)

    SARAH

    2013-02-27

    Feb 27, 2013 ... determine the pollination system of the Amazonia cocoa a focal patch observation (Frankie et al., 2002;. Potts, 2005) was undertaken to observe the regular floral insect visitors and assess their pollinator activity. Insect visitors to the 1-m section of selected cocoa trees (n=30) were carefully recorded.

  6. Regeneration of Sudanese maize inbred lines and open pollinated ...

    African Journals Online (AJOL)

    Eight maize inbred lines and three open pollinated varieties from Sudan were evaluated for their response to tissue culture. Immature embryos obtained 16 days after pollination were used as explants for callus induction. Calli were induced on LS medium supplemented with 2 mg/L 2,4-dichlorophenoxyacetic acid.

  7. The hymenopterous pollinators of Himalayan foot hills of Pakistan ...

    African Journals Online (AJOL)

    enoh

    2012-04-05

    Apr 5, 2012 ... leaf-cutting bees, alkali bees and carpenter bees are especially adopted for gathering pollens and nectars from flowers (Bohart, 1972). Pollinators other than honey bees are also extremely valuable although their value is difficult to estimate. Globally, the annual contribution of pollinators to the agricultural ...

  8. Mechanisms and evolution of deceptive pollination in orchids

    Czech Academy of Sciences Publication Activity Database

    Jersáková, Jana; Johnson, S.D.; Kindlmann, Pavel

    2006-01-01

    Roč. 81, - (2006), s. 219-235 ISSN 1464-7931 Institutional research plan: CEZ:AV0Z60870520 Keywords : cross-pollination * floral deception * geitonogamy * inbreeding * nectar * Orchidaceae * pollinaria * reward * self-pollination Subject RIV: EF - Botanics Impact factor: 5.565, year: 2006

  9. Current limiting characteristics of transformer type SFCL with coupled secondary windings according to its winding direction

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Sung Hun [Dept. of Electrical Engineering, Soongsil University, Seoul (Korea, Republic of); Han, Tae Hee [Dept. of Aero Materials Engineering, Jungwon University, Goesan (Korea, Republic of)

    2017-06-15

    In this paper, the current limiting characteristics of the transformer type superconducting fault current limiter (SFCL) with the two coupled secondary windings due to its winding direction were analyzed. To analyze the dependence of transient fault current limiting characteristics on the winding direction of the additional secondary winding, the fault current limiting tests of the SFCL with an additional secondary winding, wound as subtractive polarity winding and additive polarity winding, were carried out. The time interval of quench occurrence between two superconducting elements comprising the transformer type SFCL with the additional secondary winding was confirmed to be affected by the winding direction of the additional secondary winding. In case of the subtractive polarity winding of the additional secondary winding, the time interval of the quench occurrence in two superconducting elements was shorter than the case of the additive polarity winding.

  10. Nectar and pollination drops: how different are they?

    Science.gov (United States)

    Nepi, Massimo; von Aderkas, Patrick; Wagner, Rebecca; Mugnaini, Serena; Coulter, Andrea; Pacini, Ettore

    2009-08-01

    Pollination drops and nectars (floral nectars) are secretions related to plant reproduction. The pollination drop is the landing site for the majority of gymnosperm pollen, whereas nectar of angiosperm flowers represents a common nutritional resource for a large variety of pollinators. Extrafloral nectars also are known from all vascular plants, although among the gymnosperms they are restricted to the Gnetales. Extrafloral nectars are not generally involved in reproduction but serve as 'reward' for ants defending plants against herbivores (indirect defence). Although very different in their task, nectars and pollination drops share some features, e.g. basic chemical composition and eventual consumption by animals. This has led some authors to call these secretions collectively nectar. Modern techniques that permit chemical analysis and protein characterization have very recently added important information about these sugary secretions that appear to be much more than a 'reward' for pollinating (floral nectar) and defending animals (extrafloral nectar) or a landing site for pollen (pollination drop). Nectar and pollination drops contain sugars as the main components, but the total concentration and the relative proportions are different. They also contain amino acids, of which proline is frequently the most abundant. Proteomic studies have revealed the presence of common functional classes of proteins such as invertases and defence-related proteins in nectar (floral and extrafloral) and pollination drops. Invertases allow for dynamic rearrangement of sugar composition following secretion. Defence-related proteins provide protection from invasion by fungi and bacteria. Currently, only few species have been studied in any depth. The chemical composition of the pollination drop must be investigated in a larger number of species if eventual phylogenetic relationships are to be revealed. Much more information can be provided from further proteomic studies of both

  11. Flight of the bumble bee: Buzzes predict pollination services.

    Science.gov (United States)

    Miller-Struttmann, Nicole E; Heise, David; Schul, Johannes; Geib, Jennifer C; Galen, Candace

    2017-01-01

    Multiple interacting factors drive recent declines in wild and managed bees, threatening their pollination services. Widespread and intensive monitoring could lead to more effective management of wild and managed bees. However, tracking their dynamic populations is costly. We tested the effectiveness of an inexpensive, noninvasive and passive acoustic survey technique for monitoring bumble bee behavior and pollination services. First, we assessed the relationship between the first harmonic of the flight buzz (characteristic frequency) and pollinator functional traits that influence pollination success using flight cage experiments and a literature search. We analyzed passive acoustic survey data from three locations on Pennsylvania Mountain, Colorado to estimate bumble bee activity. We developed an algorithm based on Computational Auditory Scene Analysis that identified and quantified the number of buzzes recorded in each location. We then compared visual and acoustic estimates of bumble bee activity. Using pollinator exclusion experiments, we tested the power of buzz density to predict pollination services at the landscape scale for two bumble bee pollinated alpine forbs (Trifolium dasyphyllum and T. parryi). We found that the characteristic frequency was correlated with traits known to affect pollination efficacy, explaining 30-52% of variation in body size and tongue length. Buzz density was highly correlated with visual estimates of bumble bee density (r = 0.97), indicating that acoustic signals are predictive of bumble bee activity. Buzz density predicted seed set in two alpine forbs when bumble bees were permitted access to the flowers, but not when they were excluded from visiting. Our results indicate that acoustic signatures of flight can be deciphered to monitor bee activity and pollination services to bumble bee pollinated plants. We propose that applications of this technique could assist scientists and farmers in rapidly detecting and responding to bee

  12. Flight of the bumble bee: Buzzes predict pollination services.

    Directory of Open Access Journals (Sweden)

    Nicole E Miller-Struttmann

    Full Text Available Multiple interacting factors drive recent declines in wild and managed bees, threatening their pollination services. Widespread and intensive monitoring could lead to more effective management of wild and managed bees. However, tracking their dynamic populations is costly. We tested the effectiveness of an inexpensive, noninvasive and passive acoustic survey technique for monitoring bumble bee behavior and pollination services. First, we assessed the relationship between the first harmonic of the flight buzz (characteristic frequency and pollinator functional traits that influence pollination success using flight cage experiments and a literature search. We analyzed passive acoustic survey data from three locations on Pennsylvania Mountain, Colorado to estimate bumble bee activity. We developed an algorithm based on Computational Auditory Scene Analysis that identified and quantified the number of buzzes recorded in each location. We then compared visual and acoustic estimates of bumble bee activity. Using pollinator exclusion experiments, we tested the power of buzz density to predict pollination services at the landscape scale for two bumble bee pollinated alpine forbs (Trifolium dasyphyllum and T. parryi. We found that the characteristic frequency was correlated with traits known to affect pollination efficacy, explaining 30-52% of variation in body size and tongue length. Buzz density was highly correlated with visual estimates of bumble bee density (r = 0.97, indicating that acoustic signals are predictive of bumble bee activity. Buzz density predicted seed set in two alpine forbs when bumble bees were permitted access to the flowers, but not when they were excluded from visiting. Our results indicate that acoustic signatures of flight can be deciphered to monitor bee activity and pollination services to bumble bee pollinated plants. We propose that applications of this technique could assist scientists and farmers in rapidly detecting and

  13. Flight of the bumble bee: Buzzes predict pollination services

    Science.gov (United States)

    Heise, David; Schul, Johannes; Geib, Jennifer C.; Galen, Candace

    2017-01-01

    Multiple interacting factors drive recent declines in wild and managed bees, threatening their pollination services. Widespread and intensive monitoring could lead to more effective management of wild and managed bees. However, tracking their dynamic populations is costly. We tested the effectiveness of an inexpensive, noninvasive and passive acoustic survey technique for monitoring bumble bee behavior and pollination services. First, we assessed the relationship between the first harmonic of the flight buzz (characteristic frequency) and pollinator functional traits that influence pollination success using flight cage experiments and a literature search. We analyzed passive acoustic survey data from three locations on Pennsylvania Mountain, Colorado to estimate bumble bee activity. We developed an algorithm based on Computational Auditory Scene Analysis that identified and quantified the number of buzzes recorded in each location. We then compared visual and acoustic estimates of bumble bee activity. Using pollinator exclusion experiments, we tested the power of buzz density to predict pollination services at the landscape scale for two bumble bee pollinated alpine forbs (Trifolium dasyphyllum and T. parryi). We found that the characteristic frequency was correlated with traits known to affect pollination efficacy, explaining 30–52% of variation in body size and tongue length. Buzz density was highly correlated with visual estimates of bumble bee density (r = 0.97), indicating that acoustic signals are predictive of bumble bee activity. Buzz density predicted seed set in two alpine forbs when bumble bees were permitted access to the flowers, but not when they were excluded from visiting. Our results indicate that acoustic signatures of flight can be deciphered to monitor bee activity and pollination services to bumble bee pollinated plants. We propose that applications of this technique could assist scientists and farmers in rapidly detecting and responding to

  14. Fly pollination in Ceropegia (Apocynaceae: Asclepiadoideae): biogeographic and phylogenetic perspectives.

    Science.gov (United States)

    Ollerton, Jeff; Masinde, Siro; Meve, Ulrich; Picker, Mike; Whittington, Andrew

    2009-06-01

    Ceropegia (Apocynaceae subfamily Asclepiadoideae) is a large, Old World genus of >180 species, all of which possess distinctive flask-shaped flowers that temporarily trap pollinators. The taxonomic diversity of pollinators, biogeographic and phylogenetic patterns of pollinator exploitation, and the level of specificity of interactions were assessed in order to begin to understand the role of pollinators in promoting diversification within the genus. Flower visitor and pollinator data for approx. 60 Ceropegia taxa were analysed with reference to the main centres of diversity of the genus and to a cpDNA-nrDNA molecular phylogeny of the genus. Ceropegia spp. interact with flower-visiting Diptera from at least 26 genera in 20 families, of which 11 genera and 11 families are pollinators. Size range of flies was 0.5-4.0 mm and approx. 94 % were females. Ceropegia from particular regions do not use specific fly genera or families, though Arabian Peninsula species are pollinated by a wider range of Diptera families than those in other regions. The basal-most clade interacts with the highest diversity of Diptera families and genera, largely due to one hyper-generalist taxon, C. aristolochioides subsp. deflersiana. Species in the more-derived clades interact with a smaller diversity of Diptera. Approximately 60 % of taxa are so far recorded as interacting with only a single genus of pollinators, the remaining 40 % being less conservative in their interactions. Ceropegia spp. can therefore be ecological specialists or generalists. The genus Ceropegia has largely radiated without evolutionary shifts in pollinator functional specialization, maintaining its interactions with small Diptera. Intriguing biogeographic and phylogenetic patterns may reflect processes of regional dispersal, diversification and subsequent specialization onto a narrower range of pollinators, though some of the findings may be caused by inconsistent sampling. Comparisons are made with other plant genera

  15. Two invasive acacia species secure generalist pollinators in invaded communities

    Science.gov (United States)

    Montesinos, Daniel; Castro, Sílvia; Rodríguez-Echeverría, Susana

    2016-07-01

    Exotic entomophilous plants need to establish effective pollinator interactions in order to succeed after being introduced into a new community, particularly if they are obligatory outbreeders. By establishing these novel interactions in the new non-native range, invasive plants are hypothesised to drive changes in the composition and functioning of the native pollinator community, with potential impacts on the pollination biology of native co-flowering plants. We used two different sites in Portugal, each invaded by a different acacia species, to assess whether two native Australian trees, Acacia dealbata and Acacia longifolia, were able to recruit pollinators in Portugal, and whether the pollinator community visiting acacia trees differed from the pollinator communities interacting with native co-flowering plants. Our results indicate that in the invaded range of Portugal both acacia species were able to establish novel mutualistic interactions, predominantly with generalist pollinators. For each of the two studied sites, only two other co-occurring native plant species presented partially overlapping phenologies. We observed significant differences in pollinator richness and visitation rates among native and non-native plant species, although the study of β diversity indicated that only the native plant Lithodora fruticosa presented a differentiated set of pollinator species. Acacias experienced a large number of visits by numerous pollinator species, but massive acacia flowering resulted in flower visitation rates frequently lower than those of the native co-flowering species. We conclude that the establishment of mutualisms in Portugal likely contributes to the effective and profuse production of acacia seeds in Portugal. Despite the massive flowering of A. dealbata and A. longifolia, native plant species attained similar or higher visitation rates than acacias.

  16. Pollination ecosystem services in South African agricultural systems

    Directory of Open Access Journals (Sweden)

    Annalie Melin

    2014-11-01

    Full Text Available Insect pollinators, both managed and wild, have become a focus of global scientific, political and media attention because of their apparent decline and the perceived impact of this decline on crop production. Crop pollination by insects is an essential ecosystem service that increases the yield and quality of approximately 35% of crops worldwide. Pollinator declines are a consequence of multiple environmental pressures, e.g. habitat transformation and fragmentation, loss of floral resources, pesticides, pests and diseases, and climate change. Similar environmental pressures are faced in South Africa where there is a high demand for pollination services. In this paper, we synthesise data on the importance of different pollinators as a basis for services to South African crops and on the status of managed honeybees. We also focus on insect pollination services for the Western Cape deciduous fruit industry, which is worth ZAR9800 million per year and is heavily reliant on pollination services from managed honeybees. We discuss landscape and regional level floral resources needed to maintain sufficient numbers of managed honeybee colonies. In summary, the available literature shows a lack of data on diversity and abundance of crop pollinators, and a lack of long-term data to assess declines. We highlight key areas that require research in South Africa and emphasise the critical role of floral resource availability at the landscape and regional scale to sustain pollinators. We conclude that understanding the dynamics of how floral resources are used will help inform how landscapes could be better managed in order to provide long-term sustainable pollination services.

  17. Developing European conservation and mitigation tools for pollination services: approaches of the STEP (Status and Trends of European Pollinators) project

    NARCIS (Netherlands)

    Potts, S.G.; Biesmeijer, J.C.; Bommarco, R.; Felicioli, A.; Fischer, M.; Jokinen, P.; Kleijn, D.; Klein, A.M.; Kunin, W.E.; Neumann, P.; Penev, L.D.; Petanidou, T.; Rasmont, P.; Roberts, S.P.M.; Smith, H.G.; Sorensen, P.B.; Steffan-Dewenter, I.; Vaissiere, B.E.; Vila, M.; Vujic, A.; Woyciechowski, M.; Zobel, M.; Settele, J.; Schweiger, O.

    2011-01-01

    Pollinating insects form a key component of European biodiversity, and provide a vital ecosystem service to crops and wild plants. There is growing evidence of declines in both wild and domesticated pollinators, and parallel declines in plants relying upon them. The STEP project (Status and Trends

  18. Pollinator specificity, floral odour chemistry and the phylogeny of Australian sexually deceptive Chiloglottis orchids: implications for pollinator-driven speciation.

    Science.gov (United States)

    Peakall, Rod; Ebert, Daniel; Poldy, Jacqueline; Barrow, Russell A; Francke, Wittko; Bower, Colin C; Schiestl, Florian P

    2010-10-01

    • Sexually deceptive orchids are predicted to represent a special case of plant speciation where strong reproductive isolation may be achieved by differences in floral scent. • In this study of Australian sexually deceptive Chiloglottis orchids, we performed choice experiments to test for wasp pollinator specificity in the field; identified the compounds involved in pollinator attraction by gas chromatography with electroantennographic detection (GC-EAD), gas chromatography with mass selective detection (GC-MS), chemical synthesis and behavioural bioassays; and mapped our chemical findings on to a phylogeny of the orchids. • Field experiments confirmed pollination is a highly specific interaction, but also revealed a pool of nonpollinating 'minor responder' wasps. Six novel compounds, all 2,5-dialkylcyclohexan-1,3-diones, called 'chiloglottones', were discovered to be involved in pollinator attraction. Bioassays confirmed that pollinator specificity has a strong chemical basis, with specificity among sympatric orchids maintained by either different single compounds or a variation in a blend of two compounds. The phylogenetic overlay confirmed that speciation is always associated with pollinator switching and usually underpinned by chemical change. • If the chemical differences that control reproductive isolation in Chiloglottis have a strong genetic basis, and given the confirmed pool of potential pollinators, we conclude that pollinator-driven speciation appears highly plausible in this system. © The Authors (2010). Journal compilation © New Phytologist Trust (2010).

  19. Sticky snack for sengis: The Cape rock elephant-shrew, Elephantulus edwardii (Macroscelidea), as a pollinator of the Pagoda lily, Whiteheadia bifolia (Hyacinthaceae)

    Science.gov (United States)

    Wester, Petra

    2010-12-01

    Following the recent discovery of rodent pollination in the Pagoda lily, Whiteheadia bifolia (Hyacinthaceae) in South Africa, now the Cape rock elephant-shrew, Elephantulus edwardii (Macroscelidea, Afrotheria) is reported as an additional pollinator. Elephant-shrews, live-trapped near W. bifolia plants, were released in two terraria, containing the plants. The animals licked nectar with their long and slender tongues while being dusted with pollen and touching the stigmas of the flowers with their long and flexible noses. The captured elephant-shrews had W. bifolia pollen in their faeces, likely as a result of grooming their fur as they visited the flowers without eating or destroying them. The animals mostly preferred nectar over other food. This is the first record of pollination and nectar consumption in the primarily insectivorous E. edwardii, contributing to the very sparse knowledge about the behaviour of this unique clade of African mammals, as well as pollination by small mammals.

  20. Mounting and performance measurements of a PV array addition to an existing small wind-power installation for greenhouse electric supply in Patagonia

    Directory of Open Access Journals (Sweden)

    Rafael Oliva

    2016-08-01

    Full Text Available A small wind-power system intended for electric supply of a research greenhouse at the local University facilities in San Julian region incorporates a photovoltaic (PV array and regulator, which is described in this report together with its data-acquisition system. The main application is control and lighting. The Alternative Energy Group at the University seeks through this project to acquire knowledge and practical experience in the combination of renewable energy sources for optimal electrical supply of isolated systems, their associated measurements and processing of resulting data

  1. Projected climate change threatens pollinators and crop production in Brazil.

    Science.gov (United States)

    Giannini, Tereza Cristina; Costa, Wilian França; Cordeiro, Guaraci Duran; Imperatriz-Fonseca, Vera Lucia; Saraiva, Antonio Mauro; Biesmeijer, Jacobus; Garibaldi, Lucas Alejandro

    2017-01-01

    Animal pollination can impact food security since many crops depend on pollinators to produce fruits and seeds. However, the effects of projected climate change on crop pollinators and therefore on crop production are still unclear, especially for wild pollinators and aggregate community responses. Using species distributional modeling, we assessed the effects of climate change on the geographic distribution of 95 pollinator species of 13 Brazilian crops, and we estimated their relative impacts on crop production. We described these effects at the municipality level, and we assessed the crops that were grown, the gross production volume of these crops, the total crop production value, and the number of inhabitants. Overall, considering all crop species, we found that the projected climate change will reduce the probability of pollinator occurrence by almost 0.13 by 2050. Our models predict that almost 90% of the municipalities analyzed will face species loss. Decreases in the pollinator occurrence probability varied from 0.08 (persimmon) to 0.25 (tomato) and will potentially affect 9% (mandarin) to 100% (sunflower) of the municipalities that produce each crop. Municipalities in central and southern Brazil will potentially face relatively large impacts on crop production due to pollinator loss. In contrast, some municipalities in northern Brazil, particularly in the northwestern Amazon, could potentially benefit from climate change because pollinators of some crops may increase. The decline in the probability of pollinator occurrence is found in a large number of municipalities with the lowest GDP and will also likely affect some places where crop production is high (20% to 90% of the GDP) and where the number of inhabitants is also high (more than 6 million people). Our study highlights key municipalities where crops are economically important and where pollinators will potentially face the worst conditions due to climate change. However, pollinators may be able to

  2. Projected climate change threatens pollinators and crop production in Brazil.

    Directory of Open Access Journals (Sweden)

    Tereza Cristina Giannini

    Full Text Available Animal pollination can impact food security since many crops depend on pollinators to produce fruits and seeds. However, the effects of projected climate change on crop pollinators and therefore on crop production are still unclear, especially for wild pollinators and aggregate community responses. Using species distributional modeling, we assessed the effects of climate change on the geographic distribution of 95 pollinator species of 13 Brazilian crops, and we estimated their relative impacts on crop production. We described these effects at the municipality level, and we assessed the crops that were grown, the gross production volume of these crops, the total crop production value, and the number of inhabitants. Overall, considering all crop species, we found that the projected climate change will reduce the probability of pollinator occurrence by almost 0.13 by 2050. Our models predict that almost 90% of the municipalities analyzed will face species loss. Decreases in the pollinator occurrence probability varied from 0.08 (persimmon to 0.25 (tomato and will potentially affect 9% (mandarin to 100% (sunflower of the municipalities that produce each crop. Municipalities in central and southern Brazil will potentially face relatively large impacts on crop production due to pollinator loss. In contrast, some municipalities in northern Brazil, particularly in the northwestern Amazon, could potentially benefit from climate change because pollinators of some crops may increase. The decline in the probability of pollinator occurrence is found in a large number of municipalities with the lowest GDP and will also likely affect some places where crop production is high (20% to 90% of the GDP and where the number of inhabitants is also high (more than 6 million people. Our study highlights key municipalities where crops are economically important and where pollinators will potentially face the worst conditions due to climate change. However, pollinators

  3. Wind: French revolutions

    International Nuclear Information System (INIS)

    Jones, C.

    2006-01-01

    Despite having the second best wind resources in Europe after the UK, the wind industry in France lags behind its European counterparts with just 6 W of installed wind capacity per person. The electricity market in France is dominated by the state-owned Electricite de France (EdF) and its nuclear power stations. However, smaller renewable generators are now in theory allowed access to the market and France has transposed the EU renewables directive into national law. The French governement has set a target of generating 10,000 MW of renewable capacity by 2010. The announcement of an increased feed-in tariff and the introduction of 'development zones' (ZDEs) which could allow fast-tracking of planning for wind projects are also expected to boost wind projects. But grid access and adminstrative burdens remain major barriers. In addition, French politicians and local authorities remain committed to nuclear, though encouraged by the European Commission, wind is beginning to gain acceptance; some 325 wind farms (representing 1557 MW of capacity) were approved between February 2004 and January 2005. France is now regarded by the international wind energy sector as a target market. One of France's leading independent wind developers and its only listed wind company, Theolia, is expected to be one of the major beneficiaries of the acceleration of activity in France, though other companies are keen to maximise the opportunities for wind. France currently has only one indigenous manufacturer of wind turbines, but foreign suppliers are winning orders

  4. Insect Pollinated Crops, Insect Pollinators and US Agriculture: Trend Analysis of Aggregate Data for the Period 1992–2009

    Science.gov (United States)

    Calderone, Nicholas W.

    2012-01-01

    In the US, the cultivated area (hectares) and production (tonnes) of crops that require or benefit from insect pollination (directly dependent crops: apples, almonds, blueberries, cucurbits, etc.) increased from 1992, the first year in this study, through 1999 and continued near those levels through 2009; aggregate yield (tonnes/hectare) remained unchanged. The value of directly dependent crops attributed to all insect pollination (2009 USD) decreased from $14.29 billion in 1996, the first year for value data in this study, to $10.69 billion in 2001, but increased thereafter, reaching $15.12 billion by 2009. The values attributed to honey bees and non-Apis pollinators followed similar patterns, reaching $11.68 billion and $3.44 billion, respectively, by 2009. The cultivated area of crops grown from seeds resulting from insect pollination (indirectly dependent crops: legume hays, carrots, onions, etc.) was stable from 1992 through 1999, but has since declined. Production of those crops also declined, albeit not as rapidly as the decline in cultivated area; this asymmetry was due to increases in aggregate yield. The value of indirectly dependent crops attributed to insect pollination declined from $15.45 billion in 1996 to $12.00 billion in 2004, but has since trended upward. The value of indirectly dependent crops attributed to honey bees and non-Apis pollinators, exclusive of alfalfa leafcutter bees, has declined since 1996 to $5.39 billion and $1.15 billion, respectively in 2009. The value of alfalfa hay attributed to alfalfa leafcutter bees ranged between $4.99 and $7.04 billion. Trend analysis demonstrates that US producers have a continued and significant need for insect pollinators and that a diminution in managed or wild pollinator populations could seriously threaten the continued production of insect pollinated crops and crops grown from seeds resulting from insect pollination. PMID:22629374

  5. Insect pollinated crops, insect pollinators and US agriculture: trend analysis of aggregate data for the period 1992-2009.

    Directory of Open Access Journals (Sweden)

    Nicholas W Calderone

    Full Text Available In the US, the cultivated area (hectares and production (tonnes of crops that require or benefit from insect pollination (directly dependent crops: apples, almonds, blueberries, cucurbits, etc. increased from 1992, the first year in this study, through 1999 and continued near those levels through 2009; aggregate yield (tonnes/hectare remained unchanged. The value of directly dependent crops attributed to all insect pollination (2009 USD decreased from $14.29 billion in 1996, the first year for value data in this study, to $10.69 billion in 2001, but increased thereafter, reaching $15.12 billion by 2009. The values attributed to honey bees and non-Apis pollinators followed similar patterns, reaching $11.68 billion and $3.44 billion, respectively, by 2009. The cultivated area of crops grown from seeds resulting from insect pollination (indirectly dependent crops: legume hays, carrots, onions, etc. was stable from 1992 through 1999, but has since declined. Production of those crops also declined, albeit not as rapidly as the decline in cultivated area; this asymmetry was due to increases in aggregate yield. The value of indirectly dependent crops attributed to insect pollination declined from $15.45 billion in 1996 to $12.00 billion in 2004, but has since trended upward. The value of indirectly dependent crops attributed to honey bees and non-Apis pollinators, exclusive of alfalfa leafcutter bees, has declined since 1996 to $5.39 billion and $1.15 billion, respectively in 2009. The value of alfalfa hay attributed to alfalfa leafcutter bees ranged between $4.99 and $7.04 billion. Trend analysis demonstrates that US producers have a continued and significant need for insect pollinators and that a diminution in managed or wild pollinator populations could seriously threaten the continued production of insect pollinated crops and crops grown from seeds resulting from insect pollination.

  6. Species distribution models for crop pollination: a modelling framework applied to Great Britain.

    Science.gov (United States)

    Polce, Chiara; Termansen, Mette; Aguirre-Gutiérrez, Jesus; Boatman, Nigel D; Budge, Giles E; Crowe, Andrew; Garratt, Michael P; Pietravalle, Stéphane; Potts, Simon G; Ramirez, Jorge A; Somerwill, Kate E; Biesmeijer, Jacobus C

    2013-01-01

    Insect pollination benefits over three quarters of the world's major crops. There is growing concern that observed declines in pollinators may impact on production and revenues from animal pollinated crops. Knowing the distribution of pollinators is therefore crucial for estimating their availability to pollinate crops; however, in general, we have an incomplete knowledge of where these pollinators occur. We propose a method to predict geographical patterns of pollination service to crops, novel in two elements: the use of pollinator records rather than expert knowledge to predict pollinator occurrence, and the inclusion of the managed pollinator supply. We integrated a maximum entropy species distribution model (SDM) with an existing pollination service model (PSM) to derive the availability of pollinators for crop pollination. We used nation-wide records of wild and managed pollinators (honey bees) as well as agricultural data from Great Britain. We first calibrated the SDM on a representative sample of bee and hoverfly crop pollinator species, evaluating the effects of different settings on model performance and on its capacity to identify the most important predictors. The importance of the different predictors was better resolved by SDM derived from simpler functions, with consistent results for bees and hoverflies. We then used the species distributions from the calibrated model to predict pollination service of wild and managed pollinators, using field beans as a test case. The PSM allowed us to spatially characterize the contribution of wild and managed pollinators and also identify areas potentially vulnerable to low pollination service provision, which can help direct local scale interventions. This approach can be extended to investigate geographical mismatches between crop pollination demand and the availability of pollinators, resulting from environmental change or policy scenarios.

  7. Delivery of crop pollination services is an insufficient argument for wild pollinator conservation

    Science.gov (United States)

    Kleijn, David; Winfree, Rachael; Bartomeus, Ignasi; Carvalheiro, Luísa G; Henry, Mickaël; Isaacs, Rufus; Klein, Alexandra-Maria; Kremen, Claire; M'Gonigle, Leithen K; Rader, Romina; Ricketts, Taylor H; Williams, Neal M; Lee Adamson, Nancy; Ascher, John S; Báldi, András; Batáry, Péter; Benjamin, Faye; Biesmeijer, Jacobus C; Blitzer, Eleanor J; Bommarco, Riccardo; Brand, Mariëtte R; Bretagnolle, Vincent; Button, Lindsey; Cariveau, Daniel P; Chifflet, Rémy; Colville, Jonathan F; Danforth, Bryan N; Elle, Elizabeth; Garratt, Michael P.D.; Herzog, Felix; Holzschuh, Andrea; Howlett, Brad G; Jauker, Frank; Jha, Shalene; Knop, Eva; Krewenka, Kristin M; Le Féon, Violette; Mandelik, Yael; May, Emily A; Park, Mia G; Pisanty, Gideon; Reemer, Menno; Riedinger, Verena; Rollin, Orianne; Rundlöf, Maj; Sardiñas, Hillary S; Scheper, Jeroen; Sciligo, Amber R; Smith, Henrik G; Steffan-Dewenter, Ingolf; Thorp, Robbin; Tscharntke, Teja; Verhulst, Jort; Viana, Blandina F; Vaissière, Bernard E; Veldtman, Ruan; Westphal, Catrin; Potts, Simon G

    2015-01-01

    There is compelling evidence that more diverse ecosystems deliver greater benefits to people, and these ecosystem services have become a key argument for biodiversity conservation. However, it is unclear how much biodiversity is needed to deliver ecosystem services in a cost-effective way. Here we show that, while the contribution of wild bees to crop production is significant, service delivery is restricted to a limited subset of all known bee species. Across crops, years and biogeographical regions, crop-visiting wild bee communities are dominated by a small number of common species, and threatened species are rarely observed on crops. Dominant crop pollinators persist under agricultural expansion and many are easily enhanced by simple conservation measures, suggesting that cost-effective management strategies to promote crop pollination should target a different set of species than management strategies to promote threatened bees. Conserving the biological diversity of bees therefore requires more than just ecosystem-service-based arguments. PMID:26079893

  8. Neonicotinoid pesticide exposure impairs crop pollination services provided by bumblebees

    Science.gov (United States)

    Stanley, Dara A.; Garratt, Michael P. D.; Wickens, Jennifer B.; Wickens, Victoria J.; Potts, Simon G.; Raine, Nigel E.

    2015-12-01

    Recent concern over global pollinator declines has led to considerable research on the effects of pesticides on bees. Although pesticides are typically not encountered at lethal levels in the field, there is growing evidence indicating that exposure to field-realistic levels can have sublethal effects on bees, affecting their foraging behaviour, homing ability and reproductive success. Bees are essential for the pollination of a wide variety of crops and the majority of wild flowering plants, but until now research on pesticide effects has been limited to direct effects on bees themselves and not on the pollination services they provide. Here we show the first evidence to our knowledge that pesticide exposure can reduce the pollination services bumblebees deliver to apples, a crop of global economic importance. Bumblebee colonies exposed to a neonicotinoid pesticide provided lower visitation rates to apple trees and collected pollen less often. Most importantly, these pesticide-exposed colonies produced apples containing fewer seeds, demonstrating a reduced delivery of pollination services. Our results also indicate that reduced pollination service delivery is not due to pesticide-induced changes in individual bee behaviour, but most likely due to effects at the colony level. These findings show that pesticide exposure can impair the ability of bees to provide pollination services, with important implications for both the sustained delivery of stable crop yields and the functioning of natural ecosystems.

  9. Shift from bird to butterfly pollination in Clivia (Amaryllidaceae).

    Science.gov (United States)

    Kiepiel, Ian; Johnson, Steven D

    2014-01-01

    Pollinator shifts have been implicated as a driver of divergence in angiosperms. We tested the hypothesis that there was a transition from bird- to butterfly pollination in the African genus Clivia (Amaryllidaceae) and investigated how floral traits may have been either modified or retained during this transition. We identified pollinators using field observations, correlations between lepidopteran wing scales and pollen on stigmas, and single-visit and selective exclusion experiments. We also quantified floral rewards and advertising traits. The upright trumpet-shaped flowers of C. miniata were found to be pollinated effectively by swallowtail butterflies during both nectar-feeding and brush visits. These butterflies transfer pollen on their wings, as evidenced by positive correlations between wing scales and pollen loads on stigmas. All other Clivia species have narrow pendulous flowers that are visited by sunbirds. Selective exclusion of birds and large butterflies from flowers of two Clivia species resulted in a significant decline in seed production. From the distribution of pollination systems on available phylogenies, it is apparent that a shift took place from bird- to butterfly pollination in Clivia. This shift was accompanied by the evolution of trumpet-shaped flowers, smaller nectar volume, and emission of scent, while flower color and nectar chemistry do not appear to have been substantially modified. These results are consistent with the idea that pollinator shifts can explain major floral modifications during plant diversification.

  10. Functional group diversity of bee pollinators increases crop yield.

    Science.gov (United States)

    Hoehn, Patrick; Tscharntke, Teja; Tylianakis, Jason M; Steffan-Dewenter, Ingolf

    2008-10-07

    Niche complementarity is a commonly invoked mechanism underlying the positive relationship between biodiversity and ecosystem functioning, but little empirical evidence exists for complementarity among pollinator species. This study related differences in three functional traits of pollinating bees (flower height preference, daily time of flower visitation and within-flower behaviour) to the seed set of the obligate cross-pollinated pumpkin Cucurbita moschata Duch. ex Poir. across a land-use intensity gradient from tropical rainforest and agroforests to grassland in Indonesia. Bee richness and abundance changed with habitat variables and we used this natural variation to test whether complementary resource use by the diverse pollinator community enhanced final yield. We found that pollinator diversity, but not abundance, was positively related to seed set of pumpkins. Bees showed species-specific spatial and temporal variation in flower visitation traits and within-flower behaviour, allowing for classification into functional guilds. Diversity of functional groups explained even more of the variance in seed set (r2=45%) than did species richness (r2=32%) highlighting the role of functional complementarity. Even though we do not provide experimental, but rather correlative evidence, we can link spatial and temporal complementarity in highly diverse pollinator communities to pollination success in the field, leading to enhanced crop yield without any managed honeybees.

  11. Advances in pollination ecology from tropical plantation crops.

    Science.gov (United States)

    Klein, Alexandra-Maria; Cunningham, Saul A; Bos, Merijn; Steffan-Dewenter, Ingolf

    2008-04-01

    Although ecologists traditionally focus on natural ecosystems, there is growing awareness that mixed landscapes of managed and unmanaged systems provide a research environment for understanding basic ecological relationships on a large scale. Here, we show how tropical agroforestry systems can be used to develop ideas about the mechanisms that influence species diversity and subsequent biotic interactions at different spatial scales. Our focus is on tropical plantation crops, mainly coffee and cacao, and their pollinators, which are of basic ecological interest as partners in an important mutualistic interaction. We review how insect-mediated pollination services depend on local agroforest and natural habitats in surrounding landscapes. Further, we evaluate the functional significance of pollinator diversity and the explanatory value of species traits, and we provide an intercontinental comparison of pollinator assemblages. We found that optimal pollination success might be best understood as a consequence of niche complementarities among pollinators in landscapes harboring various species. We further show that small cavity-nesting bees and small generalist beetles were especially affected by isolation from forest and that larger-bodied insects in the same landscapes were not similarly affected. We suggest that mixed tropical landscapes with agroforestry systems have great potential for future research on the interactions between plants and pollinators.

  12. The messenger matters: Pollinator functional group influences mating system dynamics.

    Science.gov (United States)

    Weber, Jennifer J

    2017-08-01

    The incredible diversity of plant mating systems has fuelled research in evolutionary biology for over a century. Currently, there is broad concern about the impact of rapidly changing pollinator communities on plant populations. Very few studies, however, examine patterns and mechanisms associated with multiple paternity from cross-pollen loads. Often, foraging pollinators collect a mixed pollen load that may result in the deposition of pollen from different sires to receptive stigmas. Coincident deposition of self- and cross-pollen leads to interesting mating system dynamics and has been investigated in numerous species. But, mixed pollen loads often consist of a diversity of cross-pollen and result in multiple sires of seeds within a fruit. In this issue of Molecular Ecology, Rhodes, Fant, and Skogen () examine how pollinator identity and spatial isolation influence multiple paternity within fruits of a self-incompatible evening primrose. The authors demonstrate that pollen pool diversity varies between two pollinator types, hawkmoths and diurnal solitary bees. Further, progeny from more isolated plants were less likely to have multiple sires regardless of the pollinator type. Moving forward, studies of mating system dynamics should consider the implications of multiple paternity and move beyond the self- and cross-pollination paradigm. Rhodes et al. () demonstrate the importance of understanding the roles that functionally diverse pollinators play in mating system dynamics. © 2017 John Wiley & Sons Ltd.

  13. Pollinator-Driven Speciation in Sexually Deceptive Orchids

    Directory of Open Access Journals (Sweden)

    Shuqing Xu

    2012-01-01

    Full Text Available Pollinator-mediated selection has been suggested to play a major role for the origin and maintenance of the species diversity in orchids. Sexually deceptive orchids are one of the prime examples for rapid, pollinator-mediated plant radiations, with many species showing little genetic differentiation, lack of postzygotic barriers, but strong prezygotic reproductive isolation. These orchids mimic mating signals of female insects and employ male insects as pollinators. This kind of sexual mimicry leads to highly specialised pollination and provides a good system for investigating the process of pollinator-driven speciation. Here, we summarise the knowledge of key processes of speciation in this group of orchids and conduct a meta-analysis on traits that contribute to species differentiation, and thus potentially to speciation. Our study suggests that pollinator shift through changes in floral scent is predominant among closely related species in sexually deceptive orchids. Such shifts can provide a mechanism for pollinator-driven speciation in plants, if the resulting floral isolation is strong. Furthermore, changes in floral scent in these orchids are likely controlled by few genes. Together these factors suggest speciation in sexually deceptive orchids may happen rapidly and even in sympatry, which may explain the remarkable species diversity observed in this plant group.

  14. Pollination effectiveness of different strawberry floral visitors in Ribatejo, Portugal : selection of potential pollinators : Part 2

    OpenAIRE

    Albano, Sílvia; Salvado, Eva; Duarte, Sónia; Mexia, António; Borges, Paulo A. V.

    2009-01-01

    Copyright © 2009 Universita degli Studi di Firenze. This study was carried out in a strawberry (Fragaria × ananassa Duch.) field located in Ribatejo, Portugal, and aims to describe the qualitative component of the visits for three strawberry floral visitors, attaining the best results in a previous work. The main objectives were: (1) to assess the pollination rate (PR) resulting from a single visit of Apis mellifera L., Syrphidae and native bees, and (2) to characterize the foraging behavi...

  15. Cophylogenetic signal is detectable in pollination interactions across ecological scales.

    Science.gov (United States)

    Hutchinson, Matthew C; Cagua, Edgar Fernando; Stouffer, Daniel B

    2017-10-01

    That evolutionary history can influence the way that species interact is a basic tenet of evolutionary ecology. However, when the role of evolution in determining ecological interactions is investigated, focus typically centers on just one side of the interaction. A cophylogenetic signal, the congruence of evolutionary history across both sides of an ecological interaction, extends these previous explorations and provides a more complete picture of how evolutionary patterns influence the way species interact. To date, cophylogenetic signal has most typically been studied in interactions that occur between fine taxonomic clades that show high intimacy. In this study, we took an alternative approach and made an exhaustive assessment of cophylogeny in pollination interactions. To do so, we assessed the strength of cophylogenetic signal at four distinct scales of pollination interaction: (1) across plant-pollinator associations globally, (2) in local pollination communities, (3) within the modular structure of those communities, and (4) in individual modules. We did so using a globally distributed dataset comprised of 54 pollination networks, over 4000 species, and over 12,000 interactions. Within these data, we detected cophylogenetic signal at all four scales. Cophylogenetic signal was found at the level of plant-pollinator interactions on a global scale and in the majority of pollination communities. At the scale defined by the modular structure within those communities, however, we observed a much weaker cophylogenetic signal. Cophylogenetic signal was detectable in a significant proportion of individual modules and most typically when within-module phylogenetic diversity was low. In sum, the detection of cophylogenetic signal in pollination interactions across scales provides a new dimension to the story of how past evolution shapes extant pollinator-angiosperm interactions. © 2017 by the Ecological Society of America.

  16. A pollinators' eye view of a shelter mimicry system

    Science.gov (United States)

    Vereecken, Nicolas J.; Dorchin, Achik; Dafni, Amots; Hötling, Susann; Schulz, Stefan; Watts, Stella

    2013-01-01

    Background and Aims ‘Human-red’ flowers are traditionally considered to be rather unpopular with bees, yet some allogamous species in the section Oncocyclus (genus Iris, Iridaceae) have evolved specialized interactions with their pollinators, a narrow taxonomic range of male solitary bees. The dark-red, tubular flowers of these irises are nectarless but provide protective shelters (i.e. a non-nutritive form of reward) primarily to male solitary bees (Apidae, Eucerini) that pollinate the flowers while looking for a shelter. An earlier study on orchids suggested that species pollinated predominantly by male solitary bees produce significantly larger amounts and larger numbers of different n-alkenes (unsaturated cuticular hydrocarbons). Whether or not this also applies to the Oncocyclus irises and whether pollinators are attracted by specific colours or scents of these flowers is unknown. Methods Using Iris atropurpurea, recording of pollinator preferences for shelters with different spatial parameters was combined with analyses of floral colours (by spectrophotometry) and scents (by gas chromatography–mass spectrometry) to test the hypotheses that (a) pollinators significantly prefer floral tunnels facing the rising sun (floral heat-reward hypothesis), and that (b) flowers pollinated predominantly by male solitary bees produce significantly larger amounts and larger numbers of unsaturated cuticular hydrocarbons (n-alkenes) in their floral scent (preadaptation to sexual-deception hypothesis). Key Results Male bees do not significantly prefer shelters facing the rising sun or with the presence of high absolute/relative amounts and numbers of n-alkenes in the floral scent. Conclusions The results suggest that the flowers of I. atropurpurea probably evolved by pollinator-mediated selection acting primarily on floral colours to mimic large achromatic (‘bee-black’) protective shelters used preferentially by male solitary bees, and that pollinator visits are

  17. Evaluating pollination deficits in pumpkin production in New York.

    Science.gov (United States)

    Petersen, J D; Huseth, A S; Nault, B A

    2014-10-01

    Potential decreases in crop yield from reductions in bee-mediated pollination services threaten food production demands of a growing population. Many fruit and vegetable growers supplement their fields with bee colonies during crop bloom. The extent to which crop production requires supplementary pollination services beyond those provided by wild bees is not well documented. Pumpkin, Cucurbita pepo L., requires bee-mediated pollination for fruit development. Previous research identified the common eastern bumble bee, Bombus impatiens (Cresson), as the most efficient pumpkin pollinator. Two concomitant studies were conducted to examine pollination deficits in New York pumpkin fields from 2011 to 2013. In the first study, fruit weight, seed set, and B. impatiens visits to pumpkin flowers were compared across fields supplemented with B. impatiens colonies at a recommended stocking density of five colonies per hectare, a high density of 15 colonies per hectare, or not supplemented with bees. In the second study, fruit weight and seed set of pumpkins that received supplemental pollen through hand-pollination were compared with those that were open-pollinated by wild bees. Results indicated that supplementing pumpkin fields with B. impatiens colonies, regardless of stocking density, did not increase fruit weight, seed set, or B. impatiens visits to pumpkin flowers. Fruit weight and seed set did not differ between hand- and open-pollinated treatments. In general, we conclude that pumpkin production in central New York is not limited by inadequate pollination services provided by wild bees and that on average, supplementation with B. impatiens colonies did not improve pumpkin yield.

  18. Spatial structure of an individual-based plant–pollinator network

    DEFF Research Database (Denmark)

    Dupont, Yoko Luise; Nielsen, Kristian Trøjelsgaard; Hagen, Melanie

    2014-01-01

    as predictor variables revealed that thistle stems with high numbers of flower heads and many close neighbours were particularly important for connecting individuals within the modules. In contrast, tall plants and those near the patch center were crucial for connecting the different modules to each other....... This demonstrated that individual-based plant–pollinator networks are influenced by both the spatial structure of plant populations and individual-specific plant traits. Additionally, bumblebee individuals with long observation times were important for both the connectivity between and within modules. The latter......The influence of space on the structure (e.g. modularity) of complex ecological networks remains largely unknown. Here, we sampled an individual-based plant–pollinator network by following the movements and flower visits of marked bumblebee individuals within a population of thistle plants...

  19. How Pollination Ecology research can help answer important questions

    Directory of Open Access Journals (Sweden)

    Carvalheiro, Luisa G.

    2011-06-01

    Full Text Available Pollination Ecology is a dynamic field of scientific research constantly adopting novel methods and making progress in understanding the interactions between plants and their pollinators. A recent paper listed the main scientific questions in this field focussing on the ecological and biological system itself. Here, we follow up on that paper and present some ideas on how to broaden our perspective and explore the role that pollination research can play in answering both ecological and societal questions relevant to a range of different stakeholders. We hope this paper may be useful to researchers aiming at improving both the scientific and societal impact of their research.

  20. Improving predictions by cross pollination in time

    Science.gov (United States)

    Schevenhoven, Francine; Selten, Frank

    2016-04-01

    Given a set of imperfect weather models, one could ask how these models can be combined in order to improve weather predictions produced with these models. In this study we explore a technique called cross-pollination in time (CPT, Smith 2001). In the CPT approach the models exchange states during the prediction. The number of possible predictions grows quickly with time and a strategy to retain only a small number of predictions, called pruning, needs to be developed. In the learning phase a pruning strategy is proposed based on retaining those solutions that remain closest to the truth. From the learning phase probabilities are derived that determine weights to be applied to the imperfect models in the forecast phase. The CPT technique is explored using low-order dynamical systems and applied to a global atmospheric model. First results indicate that the CPT approach improves the forecast quality over the individual models.

  1. Plant survival and keystone pollinator species in stochastic coextinction models: role of intrinsic dependence on animal-pollination.

    Science.gov (United States)

    Traveset, Anna; Tur, Cristina; Eguíluz, Víctor M

    2017-07-31

    Coextinction models are useful to understand community robustness to species loss and resilience to disturbances. We simulated pollinator extinctions in pollination networks by using a hybrid model that combined a recently developed stochastic coextinction model (SCM) for plant extinctions and a topological model (TCM) for animal extinctions. Our model accounted for variation in interaction strengths and included empirical estimates of plant dependence on pollinators to set seeds. The stochastic nature of such model allowed us determining plant survival to single (and multiple) extinction events, and identifying which pollinators (keystone species) were more likely to trigger secondary extinctions. Consistently across three different pollinator removal sequences, plant robustness was lower than in a pure TCM, and plant survival was more determined by dependence on the mutualism than by interaction strength. As expected, highly connected and dependent plants were the most sensitive to pollinator loss and collapsed faster in extinction cascades. We predict that the relationship between dependence and plant connectivity is crucial to determine network robustness to interaction loss. Finally, we showed that honeybees and several beetles were keystone species in our communities. This information is of great value to foresee consequences of pollinator losses facing current global change and to identify target species for effective conservation.

  2. A spatial framework for targeting urban planning for pollinators and people with local stakeholders: A route to healthy, blossoming communities?

    Science.gov (United States)

    Bellamy, Chloe C; van der Jagt, Alexander P N; Barbour, Shelley; Smith, Mike; Moseley, Darren

    2017-10-01

    Pollinators such as bees and hoverflies are essential components of an urban ecosystem, supporting and contributing to the biodiversity, functioning, resilience and visual amenity of green infrastructure. Their urban habitats also deliver health and well-being benefits to society, by providing important opportunities for accessing nature nearby to the homes of a growing majority of people living in towns and cities. However, many pollinator species are in decline, and the loss, degradation and fragmentation of natural habitats are some of the key drivers of this change. Urban planners and other practitioners need evidence to carefully prioritise where they focus their resources to provide and maintain a high quality, multifunctional green infrastructure network that supports pollinators and people. We provide a modelling framework to inform green infrastructure planning as a nature based solution with social and ecological benefits. We show how habitat suitability models (HSM) incorporating remote sensed vegetation data can provide important information on the influence of urban landcover composition and spatial configuration on species distributions across cities. Using Edinburgh, Scotland, as a case study city, we demonstrate this approach for bumble bees and hoverflies, providing high resolution predictive maps that identify pollinator habitat hotspots and pinch points across the city. By combining this spatial HSM output with health deprivation data, we highlight 'win-win' opportunity areas in most need of improved green infrastructure to support pollinator habitat quality and connectivity, as well as societal health and well-being. In addition, in collaboration with municipal planners, local stakeholders, and partners from a local greenspace learning alliance, we identified opportunities for citizen engagement activities to encourage interest in wildlife gardening as part of a 'pollinator pledge'. We conclude that this quantitative, spatially explicit and

  3. The behaviour of Bombus impatiens (Apidae, Bombini on tomato (Lycopersicon esculentum Mill., Solanaceae flowers: pollination and reward perception

    Directory of Open Access Journals (Sweden)

    Peter Kevan

    2013-10-01

    Full Text Available The foraging behaviour of pollinators can influence their efficiency in pollinating certain plant species. Improving our understanding of this behaviour can contribute to an improvement of management techniques to avoid pollination deficits. We investigated the relationship between the number of visits of bumble bees (Bombus impatiensto tomato flowers (Lycopersicon esculentum and two variables related to the quality of the resulting fruits (weight, number of seeds, as well as the relationship between foragers’ thoracic weights, physical characteristics of thoracic vibrations (main frequency, velocity amplitude, amount of pollen removed from flowers, and the quality-related variables. In addition, we studied the capability of foragers to assess the availability of pollen in flowers. Tomato weight and seed number did not increase with the number of bee visits, neither were they correlated with the foragers’ thorax weight. Thorax weight also did not correlate with the amount of pollen removed from the flowers nor with the physical characteristics of vibration. Vibration characteristics did not change in response to the amount of pollen available on tomato flowers. Instead, foragers adjusted the time spent visiting the flowers, spending fewer time on flowers from which some pollen had already been removed on previous visits. The quantity and the production-related variables of tomatoes are not dependent on the number of bee visits (usually one visit suffices for full pollination; bigger foragers are not more efficient in pollinating tomato flowers than smaller ones; and B. impatiens foragers are capable of evaluating the amount of pollen on a flower while foraging and during pollination.

  4. Identification of Insect-Plant Pollination Networks for a Midwest Installation: Fort McCoy, WI

    Science.gov (United States)

    2016-04-01

    Pollinators and pollinator dependent plants are critical components of functioning ecosystems (Cane and Tepedino 2001). Nearly 88% of extant flowering plant ...is a pollinator species or is dependent on one. Currently, approximately 75% of 296 spe- cies at risk (SAR) flowering plants on installations are...of this study were to: (1) identify and compile infor- mation on pollinating insect fauna and pollinator dependent flowering plants for Fort McCoy

  5. Competitive context drives pollinator behavior: linking foraging plasticity, natural pollen deposition, and plant reproduction

    OpenAIRE

    Briggs, Heather Mae

    2016-01-01

    With ongoing global pollinator declines it is important to understand the functional impact of pollinator species losses. While network-based simulation models of pollinator declines predict that plant communities will be robust to losses of pollinator species, these predictions have never been tested empirically. In four chapters, my dissertation uses both empirical and modeling approaches to explore the impacts of losing pollinator species in alpine plant communities. First, I test the hypo...

  6. Contrasting Pollination Efficiency and Effectiveness among Flower Visitors of Malva Sylvestris, Borago Officinalis and Onobrychis Viciifolia

    OpenAIRE

    Gorenflo, Anna; Diekötter, Tim; van Kleunen, Mark; Wolters, Volkmar; Jauker, Frank

    2017-01-01

    Biotic pollination is an important factor for ecosystem functioning and provides a substantial ecosystem service to human food security. Not all flower visitors are pollinators, however, and pollinators differ in their pollination performances. In this study, we determined the efficiencies of flower visitors to the plant species Malva sylvestris, Borago officinalis and Onobrychis viciifolia by analysing stigmatic pollen deposition. We further calculated pollinator effectiveness by scaling up ...

  7. Adaptations for insect-trapping in brood-site pollinated Colocasia (Araceae)

    OpenAIRE

    Bröderbauer, D.; Ulrich, S.; Weber, A.

    2013-01-01

    The Araceae include both taxa with rewarding and deceptive trap pollination systems. Here we report on a genus in which rewarding and imprisonment of the pollinators co-occur. We studied the pollination of four species of Colocasia in Southwest China and investigated the morpho-anatomical adaptations of the spathe related to the attraction and capture of pollinators. All four species were pollinated by drosophilid flies of the genus Colocasiomyia. The flies are temporally arrested within the ...

  8. Perfect syncarpy in apple (Malus x domestica 'Summerland McIntosh') and its implications for pollination, seed distribution and fruit production (Rosaceae: Maloideae).

    Science.gov (United States)

    Sheffield, Cory S; Smith, Robert F; Kevan, Peter G

    2005-03-01

    The gynoecium of the domestic apple, Malus x domestica, has been assumed to be imperfectly syncarpic, whereby pollination of each stigmatic surface can result in fertilization within only one of the five carpels. Despite its implied effect on fruit quantity and quality, the resulting influence of flower form on seed set and distribution within the apple fruit has seldom been investigated. Instead, poor fruit quality is usually attributed to problems with pollination, such as low bee numbers and/or ineffective pollinators within apple agro-ecosystems. The objective of this study was to determine the true nature of gynoecial structure and its influence on fruit production in the apple cultivar 'Summerland McIntosh'. A stigma-excision method was used to determine the effects of uneven pollination among the five stigmas on fruit quantity (as measured by fruit set), and quality (seed number and distribution). In addition, flowers were examined microscopically to determine pollen tube pathways. Fruit set, seed number, seed distribution, and the microscopic examination of flower gynoecial structure reported in this study indicated that the gynoecium of the cultivar Summerland McIntosh is perfectly syncarpic and not imperfectly syncarpic as previously thought. Pollination levels among the five stigmas need not be uniform to obtain full seed development within Summerland McIntosh fruit; even if one stigmatic surface is adequately pollinated, a full complement of seeds is likely. The importance of perfect syncarpy in recognizing true causes of poor fruit quality in apple is discussed.

  9. Pollination, seed set and fruit quality in apple: studies with Osmia lignaria (Hymenoptera: Megachilidae in the Annapolis Valley, Nova Scotia, Canada

    Directory of Open Access Journals (Sweden)

    Cory Silas Sheffield

    2014-02-01

    Full Text Available The orchard crop pollinator Osmia lignaria (Hymenoptera: Megachilidae was evaluated for apple pollination in the Annapolis Valley, Nova Scotia, Canada during 2000-2001. Resulting pollination levels (measured as pollen grains on floral stigmas, percent fruit set, mature fruit weight and seed yield were evaluated against an attempted gradient of Osmia bee density. In addition, fruit quality was assessed using two symmetry indices, one based on fruit diameter, the second on fruit height. Pollination levels, percent fruit set and mature fruit quality were much higher than minimums required for adequate crop production, and all but pollination levels showed weak but significant decreases at increased distance from the established nests, suggesting that even at low numbers these bees may have been making significant contributions to apple production. Fruit were typically of better quality in areas of the orchard adjacent to Osmia nests, having fewer empty carpels and greater symmetry; fruit quality (i.e., symmetry is typically most reduced when two or more adjacent carpels are empty. Empty carpels reduce growth in fruit height rather than diameter, suggesting that symmetry indices using fruit diameter are not sensitive enough to evaluate fruit quality. Evidencing this, fruit without mature seeds observed in this study showed high symmetry based on diameter, but were greatly asymmetric with respect to fruit height. Further discussion on Osmia bees as apple pollinators and on methods of evaluating apple fruit quality with respect to seed distribution within the apple fruit are provided.

  10. Pollination of Campomanesia phaea (Myrtaceae) by night-active bees: a new nocturnal pollination system mediated by floral scent.

    Science.gov (United States)

    Cordeiro, G D; Pinheiro, M; Dötterl, S; Alves-Dos-Santos, I

    2017-03-01

    Bees are the most important diurnal pollinators of angiosperms. In several groups of bees a nocturnal/crepuscular habit developed, yet little is known about their role in pollination and whether some plants are adapted specifically to these bees. We used a multidisciplinary approach to investigate the reproductive biology and to understand the role of nocturnal/crepuscular bees in pollination of Campomanesia phaea (Myrtaceae), popularly named cambuci. We studied the floral biology and breeding system of C. phaea. We collected the floral visitors and tested the pollinators' effectiveness. We also determined the floral scents released at night and during daytime, and studied behavioural responses of crepuscular/nocturnal bees towards these scents. The flowers of cambuci were self-incompatible and had pollen as the only resource for flower visitors. Anthesis lasted around 14 h, beginning at 04:30 h at night. The flowers released 14 volatile compounds, mainly aliphatic and aromatic compounds. We collected 52 species of floral visitors, mainly bees. Nocturnal and crepuscular bees (four species) were among the most frequent species and the only effective pollinators. In field bioassays performed at night, nocturnal/crepuscular bees were attracted by a synthetic scent blend consisting of the six most abundant compounds. This study describes the first scent-mediated pollination system between a plant and its nocturnal bee pollinators. Further, C. phaea has several floral traits that do not allow classification into other nocturnal pollination syndromes (e.g. pollinator attraction already before sunrise, with pollen as the only reward), instead it is a plant specifically adapted to nocturnal bees. © 2016 German Botanical Society and The Royal Botanical Society of the Netherlands.

  11. Is floral specialization an evolutionary dead-end? Pollination system transitions in Ruellia (Acanthaceae).

    Science.gov (United States)

    Tripp, Erin A; Manos, Paul S

    2008-07-01

    Pollination systems frequently reflect adaptations to particular groups of pollinators. Such systems are indicative of evolutionary specialization and have been important in angiosperm diversification. We studied the evolution of pollination systems in the large genus Ruellia. Phylogenetic analyses, morphological ordinations, ancestral state reconstructions, and a character mapping simulation were conducted to reveal key patterns in the direction and lability of floral characters associated with pollination. We found significant floral morphological differences among species that were generally associated with different groups of floral visitors. Floral evolution has been highly labile and also directional. Some specialized systems such as hawkmoth or bat pollination are likely evolutionary dead-ends. In contrast, specialized pollination by hummingbirds is clearly not a dead-end. We found evidence for multiple reverse transitions from presumed ancestral hummingbird pollination to more derived bee or insect pollination. These repeated origins of insect pollination from hummingbird-pollinated ancestors have not evolved without historical baggage. Flowers of insect-pollinated species derived from hummingbird-pollinated ancestors are morphologically more similar to hummingbird flowers than they are to other more distantly related insect-pollinated flowers. Finally, some pollinator switches were concomitant with changes in floral morphology that are associated with those pollinators. These observations are consistent with the hypothesis that some transitions have been adaptive in the evolution of Ruellia.

  12. Wind Energy

    International Nuclear Information System (INIS)

    Rodriguez D, J.M.

    1998-01-01

    The general theory of the wind energy conversion systems is presented. The availability of the wind resource in Colombia and the ranges of the speed of the wind in those which is possible economically to use the wind turbines are described. It is continued with a description of the principal technological characteristics of the wind turbines and are split into wind power and wind-powered pumps; and its use in large quantities grouped in wind farms or in autonomous systems. Finally, its costs and its environmental impact are presented

  13. Drivers of compartmentalization in a Mediterranean pollination network

    DEFF Research Database (Denmark)

    Gonzalez, Ana M. Martin; Allesina, Stefano; Rodrigo, Anselm

    2012-01-01

    We study compartmentalization in a Mediterranean pollination network using three different analytical approaches: unipartite modularity (UM), bipartite modularity (BM) and the group model (GM). Our objectives are to compare compartments obtained with these three approaches and to explore the role...

  14. Pollinators, geitonogamy and a model of pollen transfer

    International Nuclear Information System (INIS)

    Di Pasquale, C.

    1995-12-01

    A model of pollination that considers the amount of geitonogamous pollen transfer in different flowers and plants is presented. We assumed in this work self-incompatible plant species and we studied how pollination is affected by different round trips described by pollinator from its nest, taking into account the fraction geitonogamy and the fraction pollen export. A deterministic model and a stochastic model of pollen transfer were developed from which we found that when pollinators describe a uniform sequence (visit the same number of flowers in each plant), individuals receive the maximum outcross pollen or minimum self pollen. That is, from the point of view of fertilization, the optimal number of flowers visited in each plant depends on the number of flowers of the plant, the length of the visit and the number of individuals. (author). 18 refs, 1 fig

  15. Natural cross-pollination in roselle, Hibiscus sabdariffa L. (Malvaceae

    Directory of Open Access Journals (Sweden)

    Vaidya K.R.

    2000-01-01

    Full Text Available Two local varieties of roselle (Hibiscus sabdariffa L., Jamaican Green and Jamaican Red, were grown to determine the amount of natural cross-pollination. Two planting arrangements (alternating rows; alternating individuals in a row and two planting dates, a month apart, were used for the outcrossing experiments. Stem pigmentation, red (R- vs. green (rr, was used as a genetic marker in the estimation of outcrossing. Homozygous dominant and recessive genotypes of Jamaican Red and Jamaican Green, respectively, were grown in both of the planting arrangements and dates. Seeds from open-pollinated capsules of randomly selected Jamaican Green plants were planted to score the frequency of cross-pollination. Estimates of natural cross-pollination ranged from 0.20 ± 0.09% to 0.68 ± 0.34%. Roselle outcrosses at a low rate in Jamaica.

  16. Habitat management utilizing native wildflowers to foster pollinator abundance

    Science.gov (United States)

    Pollinators provide essential ecosystem services to agricultural crops, however their population has come under threat globally as a result of intensive agricultural practices and landscape simplification. Designing diverse heterogeneous agricultural landscapes to provide optimal resources serves as...

  17. Floral scent and pollinators of the holoparasite Pilostyles thurberi (Apodanthaceae

    Directory of Open Access Journals (Sweden)

    Sedonia D Sipes

    2014-02-01

    Full Text Available Floral scent is likely important to the pollination of parasitic plants, despite that it has not been well-studied. We studied the pollination ecology of the North American stem holoparasite Pilostyles thurberi (Apodanthaceae at two field sites in Texas. To identify effective pollinators, we collected floral visitors to P. thurberi flowers, observed their foraging behavior, and looked for P. thurberi pollen on their bodies. Augochloropsis metallica bees (Halictidae and eumenine potter wasps (Vespidae were pollinators. P. thurberi flowers are visually inconspicuous but produce a strong fruity fragrance. GC/MS analysis of whole floral extracts and dynamic headspace samples revealed the fragrance to be an unusually simple bouquet of raspberry ketone and several eugenols. Comparison of scent profiles to those from uninfected host plants (Dalea formosa allowed putative separation of parasite and host volatiles. This is the first report of the constituents of floral fragrance in Apodanthaceae.

  18. Pollination and yield responses of cowpea (Vigna unguiculata L ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-05-04

    pod, the percentage of normal seeds/pod ... Key words: Apis mellifera adansonii, Vigna unguiculata, bee plant, foraging, pollination, increased yield. INTRODUCTION ... tent 23 to 25% of protein, 50 to 67% of starch and vitamin.

  19. Simple landscape modifications for pollinator and arthropod natural enemy enhancement

    Science.gov (United States)

    Beneficial arthropods which play an important role in providing ecosystem services (pollination and pest control) have come under threat as a result of intensive agricultural practices and simplification of habitats. Ecological intensification in agricultural landscapes by diversifying the habitat r...

  20. Disentangling the role of floral sensory stimuli in pollination networks

    DEFF Research Database (Denmark)

    Kantsa, Aphrodite; Raguso, Robert A.; Dyer, Adrian G.

    2018-01-01

    Despite progress in understanding pollination network structure, the functional roles of floral sensory stimuli (visual, olfactory) have never been addressed comprehensively in a community context, even though such traits are known to mediate plant-pollinator interactions. Here, we use...... a comprehensive dataset of floral traits and a novel dynamic data-pooling methodology to explore the impacts of floral sensory diversity on the structure of a pollination network in a Mediterranean scrubland. Our approach tracks transitions in the network behaviour of each plant species throughout its flowering...... period and, despite dynamism in visitor composition, reveals significant links to floral scent, and/or colour as perceived by pollinators. Having accounted for floral phenology, abundance and phylogeny, the persistent association between floral sensory traits and visitor guilds supports a deeper role...

  1. Diagnosis of directed pollination services in apple orchards in Brazil

    OpenAIRE

    Joatan Machado da Rosa; Cristiano João Arioli; Betina Blochtein; Lenita Agostinetto; Anderson Dionei Grutzmacher; Marcos Botton

    2018-01-01

    Abstract The pollination services performed by Apis mellifera are essential for the high-quality apple production. The aim of this study was to obtain information about the pollination services used in the municipalities of Vacaria-RS e São Joaquim-SC, the main apple-producing regions in Brazil. Semi-structured interviews were conducted with apple growers and technicians responsible for the orchards during 2013 and 2015. The obtained information was: a) cropping systems; b) use of pollinatio...

  2. Synergistic interactions of ecosystem services: florivorous pest control boosts crop yield increase through insect pollination

    Science.gov (United States)

    Albrecht, Matthias

    2016-01-01

    Insect pollination and pest control are pivotal functions sustaining global food production. However, they have mostly been studied in isolation and how they interactively shape crop yield remains largely unexplored. Using controlled field experiments, we found strong synergistic effects of insect pollination and simulated pest control on yield quantity and quality. Their joint effect increased yield by 23%, with synergistic effects contributing 10%, while their single contributions were 7% and 6%, respectively. The potential economic benefit for a farmer from the synergistic effects (12%) was 1.8 times greater than their individual contributions (7% each). We show that the principal underlying mechanism was a pronounced pest-induced reduction in flower lifetime, resulting in a strong reduction in the number of pollinator visits a flower receives during its lifetime. Our findings highlight the importance of non-additive interactions among ecosystem services (ES) when valuating, mapping or predicting them and reveal fundamental implications for ecosystem management and policy aimed at maximizing ES for sustainable agriculture. PMID:26865304

  3. Sex expression, breeding system and pollinators of Piper caldense (PIPERACEAE in the Brazilian Atlantic forest

    Directory of Open Access Journals (Sweden)

    Milene Faria Vieira

    2017-09-01

    Full Text Available Neotropical Piper species have bisexual flowers. Such reproductive trait is considered basal in this pantropical genus. However, neotropical species having unisexual (staminate flowers along with bisexual ones have also been reported. Dichogamy is common in the genus, associated with either self-compatibility or -incompatibility, as well as with entomophily. We analyzed a natural population of Piper caldense in a Atlantic Forest area (Viçosa municipality, Minas Gerais state, southeastern Brazil. Preliminary observations indicated that the species produces two flower types. We analyzed flower sex in spikes of 50 plants. We obtained additional information through morphological and anatomical studies and scanning electron microscopy analyses. The longevity and exposure dynamics of stigmatic papillae and the pollen release sequence of all four stamens were investigated to verify the degree of dichogamy. Pollination tests were performed, pollinators were identified and their visitation frequency was recorded. Piper caldense has both bisexual and staminate flowers, each flower type being located on separate spikes. These spikes occurred on the same plant, thus indicating andromonoecy; furthermore, plants having only spikes with staminate flowers were also observed. This gender had not yet been reported to the genus. Gradual and sequential exposure of stigmatic papillae associated with asynchronous pollen release (one stamen a day resulted in incomplete protogyny. Hand pollination tests showed that the species is self-incompatible. Social bees, mainly Apis mellifera and Melipona spp., were the major pollinator group. Our study reinforces the need to associate morphological analysis with floral biology and indicates future changes in studies addressing reproductive traits associated with the phylogeny of the Piper genus.

  4. Pollen loads and specificity of native pollinators of lowbush blueberry.

    Science.gov (United States)

    Moisan-Deserres, J; Girard, M; Chagnon, M; Fournier, V

    2014-06-01

    The reproduction of lowbush blueberry (Vaccinium angustifolium Aiton) is closely tied to insect pollination, owing to self-incompatibility. Many species are known to have greater pollination efficiency than the introduced Apis mellifera L., commonly used for commercial purposes. In this study, we measured the pollen loads of several antophilous insect species, mostly Apoidea and Syrphidae, present in four lowbush blueberry fields in Lac-St-Jean, Québec. To measure pollen loads and species specificity toward V. angustifolium, we net-collected 627 specimens of pollinators, retrieved their pollen loads, identified pollen taxa, and counted pollen grains. We found that the sizes of pollen loads were highly variable among species, ranging from a few hundred to more than 118,000 pollen grains per individual. Bombus and Andrena species in particular carried large amounts of Vaccinium pollen and thus may have greater pollination efficiency. Also, two species (Andrena bradleyi Viereck and Andrena carolina Viereck) showed nearly monolectic behavior toward lowbush blueberry. Finally, we identified alternative forage plants visited by native pollinators, notably species of Acer, Rubus, Ilex mucronata, Ledum groenlandicum, and Taraxacum. Protecting these flowering plants should be part of management practices to maintain healthy pollinator communities in a lowbush blueberry agroecosystem.

  5. Floral traits and pollination ecology of European Arum hybrids.

    Science.gov (United States)

    Chartier, Marion; Liagre, Suzanne; Weiss-Schneeweiss, Hanna; Kolano, Bozena; Bessière, Jean-Marie; Schönenberger, Jürg; Gibernau, Marc

    2016-02-01

    Hybridisation is common in plants and can affect the genetic diversity and ecology of sympatric parental populations. Hybrids may resemble the parental species in their ecology, leading to competition and/or gene introgression; alternatively, they may diverge from the parental phenotypes, possibly leading to the colonisation of new ecological niches and to speciation. Here, we describe inflorescence morphology, ploidy levels, pollinator attractive scents, and pollinator guilds of natural hybrids of Arum italicum and A. maculatum (Araceae) from a site with sympatric parental populations in southern France to determine how these traits affect the hybrid pollination ecology. Hybrids were characterised by inflorescences with a size and a number of flowers more similar to A. italicum than to A. maculatum. In most cases, hybrid stamens were purple, as in A. maculatum, and spadix appendices yellow, as in A. italicum. Hybrid floral scent was closer to that of A. italicum, but shared some compounds with A. maculatum and comprised unique compounds. Also, the pollinator guild of the hybrids was similar to that of A. italicum. Nevertheless, the hybrids attracted a high proportion of individuals of the main pollinator of A. maculatum. We discuss the effects of hybridisation in sympatric parental zones in which hybrids exhibit low levels of reproductive success, the establishment of reproductive barriers between parental species, the role of the composition of floral attractive scents in the differential attraction of pollinators and in the competition between hybrids and their parental species, and the potential of hybridisation to give rise to new independent lineages.

  6. Disentangling the role of floral sensory stimuli in pollination networks.

    Science.gov (United States)

    Kantsa, Aphrodite; Raguso, Robert A; Dyer, Adrian G; Olesen, Jens M; Tscheulin, Thomas; Petanidou, Theodora

    2018-03-12

    Despite progress in understanding pollination network structure, the functional roles of floral sensory stimuli (visual, olfactory) have never been addressed comprehensively in a community context, even though such traits are known to mediate plant-pollinator interactions. Here, we use a comprehensive dataset of floral traits and a novel dynamic data-pooling methodology to explore the impacts of floral sensory diversity on the structure of a pollination network in a Mediterranean scrubland. Our approach tracks transitions in the network behaviour of each plant species throughout its flowering period and, despite dynamism in visitor composition, reveals significant links to floral scent, and/or colour as perceived by pollinators. Having accounted for floral phenology, abundance and phylogeny, the persistent association between floral sensory traits and visitor guilds supports a deeper role for sensory bias and diffuse coevolution in structuring plant-pollinator networks. This knowledge of floral sensory diversity, by identifying the most influential phenotypes, could help prioritize efforts for plant-pollinator community restoration.

  7. Typology in pollination biology: Lessons from an historical critique

    Directory of Open Access Journals (Sweden)

    Andreas Erhardt

    2011-03-01

    Full Text Available Typological schemes that describe putative floral adaptations for pollinators have played a central role in pollination biology. In 1882 the prominent German botanist and Darwinist Hermann Müller commented critically on a precursor of modern versions of such “pollination syndromes” that had been developed by his Italian colleague Federico Delpino. Delpino also was a self-proclaimed Darwinist, but in fact adhered to teleology—explanation beyond nature. As a consequence he viewed his typology as reflecting a deeper ideal and thus as rigidly true, and rejected as unimportant any visitors to flowers that it did not predict. Although Müller also classified flowers as to pollinators, he considered such schemes to be fallible, and pondered what diversity and variation in floral visitors might mean. Müller’s comments, which we translate here, are of interest given that appeals to teleology have resurfaced from time to time in discussions of pollination syndromes, and more importantly because his warning against taking typological schemes too literally remains valid. Typology is a useful tool in biology, including pollination biology, but care must be taken that it does not replace nature as perceived reality.

  8. Crop pollination from native bees at risk from agricultural intensification.

    Science.gov (United States)

    Kremen, Claire; Williams, Neal M; Thorp, Robbin W

    2002-12-24

    Ecosystem services are critical to human survival; in selected cases, maintaining these services provides a powerful argument for conserving biodiversity. Yet, the ecological and economic underpinnings of most services are poorly understood, impeding their conservation and management. For centuries, farmers have imported colonies of European honey bees (Apis mellifera) to fields and orchards for pollination services. These colonies are becoming increasingly scarce, however, because of diseases, pesticides, and other impacts. Native bee communities also provide pollination services, but the amount they provide and how this varies with land management practices are unknown. Here, we document the individual species and aggregate community contributions of native bees to crop pollination, on farms that varied both in their proximity to natural habitat and management type (organic versus conventional). On organic farms near natural habitat, we found that native bee communities could provide full pollination services even for a crop with heavy pollination requirements (e.g., watermelon, Citrullus lanatus), without the intervention of managed honey bees. All other farms, however, experienced greatly reduced diversity and abundance of native bees, resulting in insufficient pollination services from native bees alone. We found that diversity was essential for sustaining the service, because of year-to-year variation in community composition. Continued degradation of the agro-natural landscape will destroy this "free" service, but conservation and restoration of bee habitat are potentially viable economic alternatives for reducing dependence on managed honey bees.

  9. Wind power prediction models

    Science.gov (United States)

    Levy, R.; Mcginness, H.

    1976-01-01

    Investigations were performed to predict the power available from the wind at the Goldstone, California, antenna site complex. The background for power prediction was derived from a statistical evaluation of available wind speed data records at this location and at nearby locations similarly situated within the Mojave desert. In addition to a model for power prediction over relatively long periods of time, an interim simulation model that produces sample wind speeds is described. The interim model furnishes uncorrelated sample speeds at hourly intervals that reproduce the statistical wind distribution at Goldstone. A stochastic simulation model to provide speed samples representative of both the statistical speed distributions and correlations is also discussed.

  10. Vertical axis wind turbines

    Science.gov (United States)

    Krivcov, Vladimir [Miass, RU; Krivospitski, Vladimir [Miass, RU; Maksimov, Vasili [Miass, RU; Halstead, Richard [Rohnert Park, CA; Grahov, Jurij [Miass, RU

    2011-03-08

    A vertical axis wind turbine is described. The wind turbine can include a top ring, a middle ring and a lower ring, wherein a plurality of vertical airfoils are disposed between the rings. For example, three vertical airfoils can be attached between the upper ring and the middle ring. In addition, three more vertical airfoils can be attached between the lower ring and the middle ring. When wind contacts the vertically arranged airfoils the rings begin to spin. By connecting the rings to a center pole which spins an alternator, electricity can be generated from wind.

  11. Wind Power in Electrical Distribution Systems

    DEFF Research Database (Denmark)

    Chen, Zhe

    2013-01-01

    Recent years, wind power is experiencing a rapid growth, large number of wind turbines/wind farms have been installed and connected to power systems. In addition to the large centralised wind farms connected to transmission grids, many distributed wind turbines and wind farms are operated...... as distributed generators in distribution systems. This paper discusses the issues of wind turbines in distribution systems. Wind power conversion systems briefly introduced, the basic features and technical characteristics of distributed wind power system are described, and the main technical demands...

  12. Pollination biology in the dioecious orchid Catasetum uncatum: How does floral scent influence the behaviour of pollinators?

    Science.gov (United States)

    Milet-Pinheiro, Paulo; Navarro, Daniela Maria do Amaral Ferraz; Dötterl, Stefan; Carvalho, Airton Torres; Pinto, Carlos Eduardo; Ayasse, Manfred; Schlindwein, Clemens

    2015-08-01

    Catasetum is a neotropical orchid genus that comprises about 160 dioecious species with a remarkable sexual dimorphism in floral morphology. Flowers of Catasetum produce perfumes as rewards, which are collected only by male euglossine bees. Currently, floral scents are known to be involved in the selective attraction of specific euglossine species. However, sexual dimorphism in floral scent and its eventual role in the pollination of Catasetum species have never been investigated. Here, we have investigated the pollination of Catasetum uncatum and asked: (1) Is floral scent a sexual dimorphic trait? (2) Does pollinarium removal/deposition affect scent emission? (3) Does sexual dimorphism in floral scent and changed scent emission have implications with regard to the behaviour of the pollinators? The frequency and behaviour of floral visitors were observed in non-manipulated flowers (both flower sexes) and in manipulated flowers (pistillate only) in which pollinaria were deposited. Scents of staminate and pistillate flowers (both manipulated and non-manipulated) were collected by using dynamic headspace methods and analysed chemically. Electrophysiological analyses were performed to detect compounds triggering antennal depolarisation in the euglossine species. C. uncatum is pollinated mainly by males of Euglossa nanomelanotricha. Pollinators were more frequent in pistillate than in staminate inflorescences. Bees approaching staminate flowers frequently flew away without visiting them, a behavioural pattern not observed in pistillate flowers. In the chemical analyses, we recorded 99 compounds, 31 of which triggered antennal depolarisation in pollinators. Multivariate analyses with the electrophysiological-active compounds did not detect differences between the scent composition of staminate and pistillate flowers. Pollinarium removal or deposition resulted in diminished scent emission within 24h in staminate and pistillate flowers, respectively. Surprisingly, bees

  13. Pollination effects on antioxidant content of Perilla frutescens seeds analysed by NMR spectroscopy.

    Science.gov (United States)

    Ferrazzi, Paola; Vercelli, Monica; Chakir, Amina; Romane, Abderrahmane; Mattana, Monica; Consonni, Roberto

    2017-12-01

    The effects of Perilla frutescens pollination on the content of seed antioxidants were analysed by agronomical and pollination trials, comparing seeds produced from bagged plants in 2013 (A) to prevent access to pollinating insects, and seeds from open-pollinated plants in 2013 (B) and 2015 (C). The seeds of open-pollinated plants were significantly more numerous and heavier than those of self-pollinated plants. 1 H NMR seed analysis showed a higher presence of phenolic compounds in open-pollinated seeds, mainly rosmarinic acid and flavonoids, apigenin and luteolin. Flavonoids were present in the glucosylated form in seeds (A) and (C), and in the aglycone form in seeds from (B) plants. Saturated and unsaturated fatty acids (palmitic, linoleic and linolenic) were more abundant in seeds from self-pollinated flowers. Pollination performed almost exclusively by the honeybee notably increased the antioxidant content in perilla seeds and gave rise to a reduction in the fatty acid content.

  14. High temperatures result in smaller nurseries which lower reproduction of pollinators and parasites in a brood site pollination mutualism.

    Science.gov (United States)

    Krishnan, Anusha; Pramanik, Gautam Kumar; Revadi, Santosh V; Venkateswaran, Vignesh; Borges, Renee M

    2014-01-01

    In a nursery pollination mutualism, we asked whether environmental factors affected reproduction of mutualistic pollinators, non-mutualistic parasites and seed production via seasonal changes in plant traits such as inflorescence size and within-tree reproductive phenology. We examined seasonal variation in reproduction in Ficus racemosa community members that utilise enclosed inflorescences called syconia as nurseries. Temperature, relative humidity and rainfall defined four seasons: winter; hot days, cold nights; summer and wet seasons. Syconium volumes were highest in winter and lowest in summer, and affected syconium contents positively across all seasons. Greater transpiration from the nurseries was possibly responsible for smaller syconia in summer. The 3-5°C increase in mean temperatures between the cooler seasons and summer reduced fig wasp reproduction and increased seed production nearly two-fold. Yet, seed and pollinator progeny production were never negatively related in any season confirming the mutualistic fig-pollinator association across seasons. Non-pollinator parasites affected seed production negatively in some seasons, but had a surprisingly positive relationship with pollinators in most seasons. While within-tree reproductive phenology did not vary across seasons, its effect on syconium inhabitants varied with season. In all seasons, within-tree reproductive asynchrony affected parasite reproduction negatively, whereas it had a positive effect on pollinator reproduction in winter and a negative effect in summer. Seasonally variable syconium volumes probably caused the differential effect of within-tree reproductive phenology on pollinator reproduction. Within-tree reproductive asynchrony itself was positively affected by intra-tree variation in syconium contents and volume, creating a unique feedback loop which varied across seasons. Therefore, nursery size affected fig wasp reproduction, seed production and within-tree reproductive phenology

  15. Study on Pollination and Selection of the Most Suitable Pollinizers for Commercial Pear Cultivars (Pyrus communis L. in Iran

    Directory of Open Access Journals (Sweden)

    Tatari Maryam

    2017-12-01

    Full Text Available The cultivated pear is an economically important fruit tree species of genus Pyrus in which often gametophytic self-incompatibility occurs. Therefore, this species need to be pollinated by cross-compatible cultivars that bloom in the same time. Selection of appropriate pollinizers for pear cultivars is very important to produce commercial yield. ‘Sebri’, ‘ Shahmiveh’ and ‘Natanzi’ are the best commercial cultivars in Iran, but the lack of a suitable source of pollen can reduce productivity. In order to select the most suitable pollinizer for these pear cvs, an experiment was conducted in which they were considered as pollen recipients and ‘Coscia’, ‘Bartlett’ and ‘Sardroud’ along with ‘Sebri’, ‘Shahmiveh’ and ‘Natanzi’ were evaluated as pollen donors. This research was conducted as a factorial experiment in randomized complete block design for four years. Recipient and donor cultivars had almost overlapping flowering time. The flower buds on selected branches were emasculated at balloon stage and then were counted and isolated with cotton tissue bags. Pollen grains of these pollinizers were collected in the laboratory. Isolation bags were taken off from the branches and emasculated flowers were pollinated with pollen grains of listed pollinizers during receptibility of stigma. The number of pollinated flowers was counted, and branches were covered again with the bags. The results showed that for ‘Sebri’ the best pollinizer was ‘Coscia’ with 5.7% fruit set, for ‘Shahmiveh’ ‘Bartlett’ cv. with 5.8% of fruit set and for ‘Natanzi’, ‘Shahmiveh’ with 5.5% of fruit set.

  16. High temperatures result in smaller nurseries which lower reproduction of pollinators and parasites in a brood site pollination mutualism.

    Directory of Open Access Journals (Sweden)

    Anusha Krishnan

    Full Text Available In a nursery pollination mutualism, we asked whether environmental factors affected reproduction of mutualistic pollinators, non-mutualistic parasites and seed production via seasonal changes in plant traits such as inflorescence size and within-tree reproductive phenology. We examined seasonal variation in reproduction in Ficus racemosa community members that utilise enclosed inflorescences called syconia as nurseries. Temperature, relative humidity and rainfall defined four seasons: winter; hot days, cold nights; summer and wet seasons. Syconium volumes were highest in winter and lowest in summer, and affected syconium contents positively across all seasons. Greater transpiration from the nurseries was possibly responsible for smaller syconia in summer. The 3-5°C increase in mean temperatures between the cooler seasons and summer reduced fig wasp reproduction and increased seed production nearly two-fold. Yet, seed and pollinator progeny production were never negatively related in any season confirming the mutualistic fig-pollinator association across seasons. Non-pollinator parasites affected seed production negatively in some seasons, but had a surprisingly positive relationship with pollinators in most seasons. While within-tree reproductive phenology did not vary across seasons, its effect on syconium inhabitants varied with season. In all seasons, within-tree reproductive asynchrony affected parasite reproduction negatively, whereas it had a positive effect on pollinator reproduction in winter and a negative effect in summer. Seasonally variable syconium volumes probably caused the differential effect of within-tree reproductive phenology on pollinator reproduction. Within-tree reproductive asynchrony itself was positively affected by intra-tree variation in syconium contents and volume, creating a unique feedback loop which varied across seasons. Therefore, nursery size affected fig wasp reproduction, seed production and within

  17. High Temperatures Result in Smaller Nurseries which Lower Reproduction of Pollinators and Parasites in a Brood Site Pollination Mutualism

    Science.gov (United States)

    Krishnan, Anusha; Pramanik, Gautam Kumar; Revadi, Santosh V.; Venkateswaran, Vignesh; Borges, Renee M.

    2014-01-01

    In a nursery pollination mutualism, we asked whether environmental factors affected reproduction of mutualistic pollinators, non-mutualistic parasites and seed production via seasonal changes in plant traits such as inflorescence size and within-tree reproductive phenology. We examined seasonal variation in reproduction in Ficus racemosa community members that utilise enclosed inflorescences called syconia as nurseries. Temperature, relative humidity and rainfall defined four seasons: winter; hot days, cold nights; summer and wet seasons. Syconium volumes were highest in winter and lowest in summer, and affected syconium contents positively across all seasons. Greater transpiration from the nurseries was possibly responsible for smaller syconia in summer. The 3–5°C increase in mean temperatures between the cooler seasons and summer reduced fig wasp reproduction and increased seed production nearly two-fold. Yet, seed and pollinator progeny production were never negatively related in any season confirming the mutualistic fig–pollinator association across seasons. Non-pollinator parasites affected seed production negatively in some seasons, but had a surprisingly positive relationship with pollinators in most seasons. While within-tree reproductive phenology did not vary across seasons, its effect on syconium inhabitants varied with season. In all seasons, within-tree reproductive asynchrony affected parasite reproduction negatively, whereas it had a positive effect on pollinator reproduction in winter and a negative effect in summer. Seasonally variable syconium volumes probably caused the differential effect of within-tree reproductive phenology on pollinator reproduction. Within-tree reproductive asynchrony itself was positively affected by intra-tree variation in syconium contents and volume, creating a unique feedback loop which varied across seasons. Therefore, nursery size affected fig wasp reproduction, seed production and within-tree reproductive

  18. Pollination of Greenhouse Tomatoes by the Mexican bumblebee Bombus ephippiatus (Hymenoptera: Apidae

    Directory of Open Access Journals (Sweden)

    Carlos Hernan Vergara

    2012-04-01

    Full Text Available The Mexican native bumblebee Bombus ephippiatus Say was evaluated as a potential pollinator of greenhouse tomatoes (Solanum lycopersicon L.. The experiments were performed at San Andrés Cholula, Puebla, Mexico, from June to December 2004 in two 1 000 m2 greenhouses planted with tomatoes of the cultivar Mallory (Hazera ®. For the experiments, we used two colonies of Bombus ephippiatus, reared in the laboratory from queens captured in the field. Four treatments were applied to 20 study plants: pollination by bumble bees, manual pollination, pollination by mechanical vibration and no pollination (bagged flowers, no vibration. We measured percentage of flowers visited by bumble bees, number of seeds per fruit, maturing time, sugar content, fruit weight and fruit shape. All available flowers were visited by bumblebees, as measured by the degree of anther cone bruising. The number of seeds per fruit was higher for bumble bee-pollinated plants as compared with plants pollinated mechanically or not pollinated and was not significantly different between hand-pollinated and bumble bee-pollinated plants. Maturation time was significantly longer and sugar content, fresh weight and seed count were significantly higher for bumblebee pollinated flowers than for flowers pollinated manually or with no supplemental pollination, but did not differ with flowers pollinated mechanically.

  19. Wind Atlas of Bay of Bengal with Satellite Wind Measurement

    DEFF Research Database (Denmark)

    Nadi, Navila Rahman

    footstep towards offshore wind energy analysis for this region. Generally, it is difficult to find offshore wind data relative to the wind turbine hub heights, therefore a starting point is necessary to identify the possible wind power density of the region. In such scenario, Synthetic aperture radars (SAR......The objective of this study is to obtain appropriate offshore location in the Bay of Bengal, Bangladesh for further development of wind energy. Through analyzing the previous published works, no offshore wind energy estimation has been found here. That is why, this study can be claimed as the first......) have proven useful. In this study, SAR based dataset- ENVISAT ASAR has been used for Wind Atlas generation. Furthermore, a comparative study has been performed with Global Wind Atlas (GWA) to determine a potential offshore wind farm. Additionally, the annual energy production of that offshore windfarm...

  20. Interacting effects of pollination, water and nutrients on fruit tree performance.

    Science.gov (United States)

    Klein, A-M; Hendrix, S D; Clough, Y; Scofield, A; Kremen, C

    2015-01-01

    Pollination is critical to fruit production, but the interactions of pollination with plant resources on a plant's reproductive and vegetative features are largely overlooked. We examined the influences of pollination, irrigation and fertilisation on the performance of almond, Prunus dulcis, in northern California. We used a full-factorial design to test for the effects of pollination limitation on fruit production and foliage variables of whole trees experiencing four resource treatments: (i) normal water and nutrients, (ii) reduced water, (iii) no nutrients, and (iv) reduced water and no nutrients. In each of these combinations, we applied three pollination treatments: hand-cross pollination, open-pollination and pollinator exclusion. Pollination strongly affected yield even under reduced water and no nutrient applications. Hand-cross pollination resulted in over 50% fruit set with small kernels, while open-pollinated flowers showed over 30% fruit set with moderate-sized kernels. Pollinator-excluded flowers had a maximum fruit set of 5%, with big and heavy kernels. Reduced water interacted with the open- and hand-cross pollination treatments, reducing yield more than in the pollinator exclusion treatment. The number of kernels negatively influenced the number of leaves, and reduced water and no nutrient applications interacted with the pollination treatments. Overall, our results indicate that the influences of pollination on fruit tree yield interact with the plant availability of nutrients and water and that excess pollination can reduce fruit quality and the production of leaves for photosynthesis. Such information is critical to understand how pollination influences fruit tree performance. © 2014 German Botanical Society and The Royal Botanical Society of the Netherlands.

  1. Spatio-temporal patterns in pollination of deceptive Aristolochia rotunda L. (Aristolochiaceae).

    Science.gov (United States)

    Oelschlägel, B; von Tschirnhaus, M; Nuss, M; Nikolić, T; Wanke, S; Dötterl, S; Neinhuis, C

    2016-11-01

    Pollination success of highly specialised flowers is susceptible to fluctuations of the pollinator fauna. Mediterranean Aristolochia rotunda has deceptive trap flowers exhibiting a highly specialised pollination system. The sole pollinators are kleptoparasitic flies in search of food. This study investigates these pollinators on a spatio-temporal scale and the impact of weather conditions on their availability. Two potential strategies of the plants to cope with pollinator limitation, i.e. autonomous selfing and an increased floral life span, were tested. A total of 6156 flowers were investigated for entrapped pollinators in 10 Croatian populations. Availability of the main pollinator was correlated to meteorological data. Artificial pollination experiments were conducted and the floral life span was recorded in two populations according to pollinator availability. Trachysiphonella ruficeps (Chloropidae) was identified as dominant pollinator, along with less abundant species of Chloropidae, Ceratopogonidae and Milichiidae. Pollinator compositions varied among populations. Weather conditions 15-30 days before pollination had a significant effect on availability of the main pollinator. Flowers were not autonomously selfing, and the floral life span exhibited considerable plasticity depending on pollinator availability. A. rotunda flowers rely on insect pollen vectors. Plants are specialised on a guild of kleptoparasitic flies, rather than on a single species. Pollinator variability may result in differing selection pressures among populations. The availability/abundance of pollinators depends on weather conditions during their larval development. Flowers show a prolonged trapping flower stage that likely increases outcrossing success during periods of pollinator limitation. © 2016 German Botanical Society and The Royal Botanical Society of the Netherlands.

  2. Electrostatic Charge on Flying Hummingbirds and Its Potential Role in Pollination.

    Science.gov (United States)

    Badger, Marc; Ortega-Jimenez, Victor Manuel; von Rabenau, Lisa; Smiley, Ashley; Dudley, Robert

    2015-01-01

    Electrostatic phenomena are known to enhance both wind- and insect-mediated pollination, but have not yet been described for nectar-feeding vertebrates. Here we demonstrate that wild Anna's Hummingbirds (Calypte anna) can carry positive charges up to 800 pC while in flight (mean ± s.d.: 66 ± 129 pC). Triboelectric charging obtained by rubbing an isolated hummingbird wing against various plant structures generated charges up to 700 pC. A metal hummingbird model charged to 400 pC induced bending of floral stamens in four plants (Nicotiana, Hemerocallis, Penstemon, and Aloe spp.), and also attracted falling Lycopodium spores at distances of < 2 mm. Electrostatic forces may therefore influence pollen transfer onto nectar-feeding birds.

  3. Electrostatic Charge on Flying Hummingbirds and Its Potential Role in Pollination.

    Directory of Open Access Journals (Sweden)

    Marc Badger

    Full Text Available Electrostatic phenomena are known to enhance both wind- and insect-mediated pollination, but have not yet been described for nectar-feeding vertebrates. Here we demonstrate that wild Anna's Hummingbirds (Calypte anna can carry positive charges up to 800 pC while in flight (mean ± s.d.: 66 ± 129 pC. Triboelectric charging obtained by rubbing an isolated hummingbird wing against various plant structures generated charges up to 700 pC. A metal hummingbird model charged to 400 pC induced bending of floral stamens in four plants (Nicotiana, Hemerocallis, Penstemon, and Aloe spp., and also attracted falling Lycopodium spores at distances of < 2 mm. Electrostatic forces may therefore influence pollen transfer onto nectar-feeding birds.

  4. Some pollinators are more equal than others: Factors influencing pollen loads and seed set capacity of two actively and passively pollinating fig wasps

    Science.gov (United States)

    Kjellberg, Finn; Suleman, Nazia; Raja, Shazia; Tayou, Abelouahad; Hossaert-McKey, Martine; Compton, Stephen G.

    2014-05-01

    The nursery pollination system of fig trees (Ficus) results in the plants providing resources for pollinator fig wasp larvae as part of their male reproductive investment, with selection determining relative investment into pollinating wasps and the pollen they carry. The small size of Ficus pollen suggests that the quantities of pollen transported by individual wasps often limits male reproductive success. We assessed variation in fig wasp pollen loads and its influence on seed production in actively pollinated (Ficus montana) and passively pollinated (Ficus carica) dioecious fig trees.

  5. Mechanisms and evolution of deceptive pollination in orchids.

    Science.gov (United States)

    Jersáková, Jana; Johnson, Steven D; Kindlmann, Pavel

    2006-05-01

    The orchid family is renowned for its enormous diversity of pollination mechanisms and unusually high occurrence of non-rewarding flowers compared to other plant families. The mechanisms of deception in orchids include generalized food deception, food-deceptive floral mimicry, brood-site imitation, shelter imitation, pseudoantagonism, rendezvous attraction and sexual deception. Generalized food deception is the most common mechanism (reported in 38 genera) followed by sexual deception (18 genera). Floral deception in orchids has been intensively studied since Darwin, but the evolution of non-rewarding flowers still presents a major puzzle for evolutionary biology. The two principal hypotheses as to how deception could increase fitness in plants are (i) reallocation of resources associated with reward production to flowering and seed production, and (ii) higher levels of cross-pollination due to pollinators visiting fewer flowers on non-rewarding plants, resulting in more outcrossed progeny and more efficient pollen export. Biologists have also tried to explain why deception is overrepresented in the orchid family. These explanations include: (i) efficient removal and deposition of pollinaria from orchid flowers in a single pollinator visit, thus obviating the need for rewards to entice multiple visits from pollinators; (ii) efficient transport of orchid pollen, thus requiring less reward-induced pollinator constancy; (iii) low-density populations in many orchids, thus limiting the learning of associations of floral phenotypes and rewards by pollinators; (iv) packaging of pollen in pollinaria with limited carry-over from flower to flower, thus increasing the risks of geitonogamous self-pollination when pollinators visit many flowers on rewarding plants. All of these general and orchid-specific hypotheses are difficult to reconcile with the well-established pattern for rewardlessness to result in low pollinator visitation rates and consequently low levels of fruit

  6. Population Genetic Aspects of Pollinator Decline

    Directory of Open Access Journals (Sweden)

    Laurence Packer

    2001-06-01

    Full Text Available We reviewed the theory of conservation genetics, with special emphasis on the influence of haplodiploidy and other aspects of bee biology upon conservation genetic parameters. We then investigated the possibility that pollinator decline can be addressed in this way, using two meta-analytical approaches on genetic data from the Hymenoptera and the Lepidoptera. First, we compared levels of heterozygosity between the orders. As has been found previously, the haplodiploid Hymenoptera had markedly lower levels of genetic variation than the Lepidoptera. Bees had even lower levels, and bumble bees, in particular, often seemed almost monomorphic genetically. However, the statistically confounding effects of phylogeny render detailed interpretation of such data difficult. Second, we investigated patterns of gene flow among populations of these insects. Hymenoptera were far more likely to show genetic effects of population fragmentation than are Lepidoptera, even at similar geographic distances between populations. The reduced effective population sizes resulting from haplodiploidy probably contributed to this result. The proportion of species with low levels of gene flow did not vary among the different taxonomic groups within the Hymenoptera.

  7. Number of conspecifics and reproduction in the invasive plant Eschscholzia californica (Papaveraceae): is there a pollinator-mediated Allee effect?

    Science.gov (United States)

    Anic, V; Henríquez, C A; Abades, S R; Bustamante, R O

    2015-05-01

    The component Allee effect has been defined as 'a positive relationship between any measure of individual fitness and the number or density of conspecifics'. Larger plant populations or large patches have shown a higher pollinator visitation rate, which may give rise to an Allee effect in reproduction of the plants. We experimentally tested the effect of number of conspecifics on reproduction and pollinator visitation in Eschscholzia californica Cham., an invasive plant in Chile. We then built patches with two, eight and 16 flowering individuals of E. californica (11 replicates per treatment) in an area characterised by dominance of the study species. We found that E. californica exhibits a component Allee effect, as the number of individuals of this species has a positive effect on individual seed set. However, individual fruit production was not affected by the number of plants examined. Pollinator visitation rate was also independent of the number of plants, so this factor would not explain the Allee effect. This rate was positively correlated with the total number of flowers in the patches. We also found that the number of plants did not affect the seed mass or proportion of germinated seeds in the patches. Higher pollen availability in patches with 16 plants and pollination by wind could explain the Allee effect. The component Allee effect identified could lead to a weak demographic Allee effect that might reduce the rate of spread of E. californica. Knowledge of this would be useful for management of this invasive plant in Chile. © 2014 German Botanical Society and The Royal Botanical Society of the Netherlands.

  8. Pseudocopulatory Pollination in Lepanthes (Orchidaceae: Pleurothallidinae) by Fungus Gnats

    Science.gov (United States)

    BLANCO, MARIO A.; BARBOZA, GABRIEL

    2005-01-01

    • Background and Aims Lepanthes is one of the largest angiosperm genera (>800 species). Their non-rewarding, tiny and colourful flowers are structurally complex. Their pollination mechanism has hitherto remained unknown, but has been subject of ample speculation; the function of the minuscule labellum appendix is especially puzzling. Here, the pollination of L. glicensteinii by sexually deceived male fungus gnats is described and illustrated. • Methods Visitors to flowers of L. glicensteinii were photographed and their behaviour documented; some were captured for identification. Occasional visits to flowers of L. helleri, L. stenorhyncha and L. turialvae were also observed. Structural features of flowers and pollinators were studied with SEM. • Key Results Sexually aroused males of the fungus gnat Bradysia floribunda (Diptera: Sciaridae) were the only visitors and pollinators of L. glicensteinii. The initial long-distance attractant seems to be olfactory. Upon finding a flower, the fly curls his abdomen under the labellum and grabs the appendix with his genitalic claspers, then dismounts the flower and turns around to face away from it. The pollinarium attaches to his abdomen during this pivoting manoeuvre. Pollinia are deposited on the stigma during a subsequent flower visit. The flies appear to ejaculate during pseudocopulation. The visitors of L. helleri, L. stenorhyncha and L. turialvae are different species of fungus gnats that display a similar behaviour. • Conclusions Lepanthes glicensteinii has genitalic pseudocopulatory pollination, the first case reported outside of the Australian orchid genus Cryptostylis. Since most species of Lepanthes have the same unusual flower structure, it is predicted that pollination by sexual deception is prevalent in the genus. Several morphological and phenological traits in Lepanthes seem well suited for exploiting male fungus gnats as pollinators. Correspondingly, some demographic trends common in Lepanthes are

  9. The effect of habitat modification on plant-pollinator network

    Science.gov (United States)

    Aminatun, Tien; Putra, Nugroho Susetya

    2017-08-01

    The research aimed to determine; (1) the mutualism interaction pattern of plant-pollinator on several habitat modifications; and (2) the habitat modification which showed the most stable pattern of interaction. The study was conducted in one planting season with 20 plots which each plot had 2x2 m2 width and 2 m spacing among plots, and each plot was planted with the same variety of tomato plants, i.e. "intan". Nitrogen manipulation treatment was conducted with four kinds of fertilizers, i.e. NPK (code PU), compost (code PKM), vermicompost (code PC), and manure (code PK). Each treatment had 5 plot replications. We observed the growth of tomato plants, weed and arthropod populationstwo weekly while pollinator visitation twice a week during tomato plant flowering with counting population and visitation frequence of each pollinator on each sample of tomato plants. The nectar of tomato plant flower of each treatment was tested in laboratory to see its reducing sugar and sucrose. Oganic matter and nitrogen of the soil samples of each treatment were tested in laboratory in the beginning and the end of this research. We analized the plant-pollinator network with bipartite program in R-statistics, and the abiotic and other biotic factors with descriptive analysis. The results of the research were; (1) the mutualism interaction pattern of plant-pollinator network of four treatments were varied, and (2) The pattern of plant-pollinator network of NPK fertilizer treatment showed the more stable interaction based on analysis of interaction evenness, Shannon diversity, frequency and longevity of pollinator visitation.

  10. Insights from the pollination drop proteome and the ovule transcriptome of Cephalotaxus at the time of pollination drop production.

    Science.gov (United States)

    Pirone-Davies, Cary; Prior, Natalie; von Aderkas, Patrick; Smith, Derek; Hardie, Darryl; Friedman, William E; Mathews, Sarah

    2016-05-01

    Many gymnosperms produce an ovular secretion, the pollination drop, during reproduction. The drops serve as a landing site for pollen, but also contain a suite of ions and organic compounds, including proteins, that suggests diverse roles for the drop during pollination. Proteins in the drops of species of Chamaecyparis, Juniperus, Taxus, Pseudotsuga, Ephedra and Welwitschia are thought to function in the conversion of sugars, defence against pathogens, and pollen growth and development. To better understand gymnosperm pollination biology, the pollination drop proteomes of pollination drops from two species of Cephalotaxus have been characterized and an ovular transcriptome for C. sinensis has been assembled. Mass spectrometry was used to identify proteins in the pollination drops of Cephalotaxus sinensis and C. koreana RNA-sequencing (RNA-Seq) was employed to assemble a transcriptome and identify transcripts present in the ovules of C. sinensis at the time of pollination drop production. About 30 proteins were detected in the pollination drops of both species. Many of these have been detected in the drops of other gymnosperms and probably function in defence, polysaccharide metabolism and pollen tube growth. Other proteins appear to be unique to Cephalotaxus, and their putative functions include starch and callose degradation, among others. Together, the proteins appear either to have been secreted into the drop or to occur there due to breakdown of ovular cells during drop production. Ovular transcripts represent a wide range of gene ontology categories, and some may be involved in drop formation, ovule development and pollen-ovule interactions. The proteome of Cephalotaxus pollination drops shares a number of components with those of other conifers and gnetophytes, including proteins for defence such as chitinases and for carbohydrate modification such as β-galactosidase. Proteins likely to be of intracellular origin, however, form a larger component of drops

  11. Wind Structure and Wind Loading

    DEFF Research Database (Denmark)

    Brorsen, Michael

    The purpose of this note is to provide a short description of wind, i.e. of the flow in the atmosphere of the Earth and the loading caused by wind on structures. The description comprises: causes to the generation of windhe interaction between wind and the surface of the Earthhe stochastic nature...... of windhe interaction between wind and structures, where it is shown that wind loading depends strongly on this interaction...

  12. Effects of pollination timing and distance on seed production in a dioecious weed Silene latifolia

    Science.gov (United States)

    Anderson, Jay F.; Duddu, Hema S. N.; Shirtliffe, Steven J.; Benaragama, Dilshan; Syrovy, Lena D.; Stanley, Katherine A.; Haile, Teketel A.

    2015-11-01

    Silene latifolia Poir. (white cockle or white campion) is an important invasive weed in North American agriculture. It exhibits dioecy, therefore, both male and female plants are required in order for seed production to occur. However, dioecious species being invasive is not common because of their limitations in pollination and subsequent seed production. The objective of this study is to determine the effect of pollination timing and distance on seed production of Silene latifolia. A series of experiments including pollination exclusion, timing and pollination distance were conducted in 2009 and 2010 at or around Saskatoon, Saskatchewan. For pollination exclusion, exclosures were built around the natural female plants for exclosure, sham-exclosure, and male and female combined treatments. Pollination timing was studied by applying exclosure, non-exclosure, night-exclosure, and day-exclosure treatments to individual female plants. Female plants were transplanted along a linear interval at six different distances from the pollen source to study the effect of pollination distance. S. latifolia was exclusively insect-pollinated and pollination occurred both day and night; however, in one year, pollination occurred mainly at night. Female plants that were in the range of 0-4 m from a compatible pollen source experienced no limitation to pollination. However, when the distance was increased further up to 128 m, pollination levels and subsequent seed production were declined. Moreover, there were differences in seed production between years suggesting that pollination was affected by the environmental conditions during pollination and the crop that white cockle was grown in. These experiments indicate that seed production in S. latifolia is limited by insect-pollination. Although there was pollination limitation for seed production at greater distances from a pollen source, the high fecundity rate (3000-18000 seeds per plant) resulted in a large seed output. Thus, we

  13. Functional morphology and wasp pollination of two South American asclepiads (Asclepiadoideae–Apocynaceae)

    Science.gov (United States)

    Wiemer, A. P.; Sérsic, A. N.; Marino, S.; Simões, A. O.; Cocucci, A. A.

    2012-01-01

    Background and Aims The extreme complexity of asclepiad flowers (Asclepiadoideae–Apocynaceae) has generated particular interest in the pollination biology of this group of plants especially in the mechanisms involved in the pollination processes. This study compares two South American species, Morrenia odorata and Morrenia brachystephana, with respect to morphology and anatomy of flower structures, dynamic aspects of the pollination mechanism, diversity of visitors and effectiveness of pollinators. Methods Floral structure was studied with fresh and fixed flowers following classical techniques. The pollination mechanism was studied by visiting fresh flowers in the laboratory with artificial pollinator body parts created with an eyelash. Morphometric and nectar measurements were also taken. Pollen transfer efficiency in the flowers was calculated by recording the frequency of removed and inserted pollinia. Visitor activity was recorded in the field, and floral visitors were captured for subsequent analysis of pollen loads. Finally, pollinator effectiveness was calculated with an index. Key Results The detailed structure of the flowers revealed a complex system of guide rails and chambers precisely arranged in order to achieve effective pollinaria transport. Morrenia odorata is functionally specialized for wasp pollination, and M. brachystephana for wasp and bee pollination. Pollinators transport chains of pollinaria adhered to their mouthparts. Conclusions Morrenia odorata and M. brachystephana present differences in the morphology and size of their corona, gynostegium and pollinaria, which explain the differences in details of the functioning of the general pollination mechanism. Pollination is performed by different groups of highly effective pollinators. Morrenia species are specialized for pollination mainly by several species of wasps, a specialized pollination which has been poorly studied. In particular, pompilid wasps are reported as important pollinators

  14. Functional morphology and wasp pollination of two South American asclepiads (Asclepiadoideae-Apocynaceae).

    Science.gov (United States)

    Wiemer, A P; Sérsic, A N; Marino, S; Simões, A O; Cocucci, A A

    2012-01-01

    BACKGROUND AND AIMS The extreme complexity of asclepiad flowers (Asclepiadoideae-Apocynaceae) has generated particular interest in the pollination biology of this group of plants especially in the mechanisms involved in the pollination processes. This study compares two South American species, Morrenia odorata and Morrenia brachystephana, with respect to morphology and anatomy of flower structures, dynamic aspects of the pollination mechanism, diversity of visitors and effectiveness of pollinators. Floral structure was studied with fresh and fixed flowers following classical techniques. The pollination mechanism was studied by visiting fresh flowers in the laboratory with artificial pollinator body parts created with an eyelash. Morphometric and nectar measurements were also taken. Pollen transfer efficiency in the flowers was calculated by recording the frequency of removed and inserted pollinia. Visitor activity was recorded in the field, and floral visitors were captured for subsequent analysis of pollen loads. Finally, pollinator effectiveness was calculated with an index. The detailed structure of the flowers revealed a complex system of guide rails and chambers precisely arranged in order to achieve effective pollinaria transport. Morrenia odorata is functionally specialized for wasp pollination, and M. brachystephana for wasp and bee pollination. Pollinators transport chains of pollinaria adhered to their mouthparts. Morrenia odorata and M. brachystephana present differences in the morphology and size of their corona, gynostegium and pollinaria, which explain the differences in details of the functioning of the general pollination mechanism. Pollination is performed by different groups of highly effective pollinators. Morrenia species are specialized for pollination mainly by several species of wasps, a specialized pollination which has been poorly studied. In particular, pompilid wasps are reported as important pollinators in other regions outside South

  15. Field Experiments of Pollination Ecology: The Case of Lycoris sanguinea var. sanguinea.

    Science.gov (United States)

    Yamaji, Futa; Ohsawa, Takeshi A

    2016-11-25

    Plant-pollinator interactions have been studied for approximately one hundred years. During that time, many field methods have been developed to clarify the pollination effectiveness of each pollinator for visited flowers. Pollinator observations have been one of the most common methods to identify pollinators, and bagging and cage experiments have been conducted to show the effectiveness of specific pollinators. In a previous study of Lycoris sanguinea var. sanguinea, its effective pollinators, the visitation frequencies of each floral visitor, and its reproductive strategies were not identified. This study reports the observation that small bees visited flowers that were partially opened (breaking buds). To the best of our knowledge, this phenomenon has not been reported previously. Further, this study investigates the hypothesis that small bees can pollinate at that flowering stage. This study demonstrates the basic methods of field experiments in pollination ecology using L. sanguinea var. sanguinea. Pollinator observations and digital video showed the visitation frequencies of each floral visitor. Bagging and cage experiments revealed that these flowers could be pollinated fully and that breaking-bud pollination could be important for the pollination of this plant species. The advantages and disadvantages of each method are discussed, and recent developments, including laboratory experiments, are described.

  16. Wind flow through shrouded wind turbines

    Science.gov (United States)

    2017-03-01

    velocity and model angle were varied . Additionally, static wall pressures and cross section flow were studied with the addition of a screen. The pressure...the geometry of a wind lens or flange on the shroud and a gradually diverging shape, proved to accelerate the flow through the duct. 14. SUBJECT...Tunnel velocity and model angle were varied . Additionally, static wall pressures and cross section flow were studied with the addition of a screen. The

  17. Evolutionary dynamics of a cycad obligate pollination mutualism - Pattern and process in extant Macrozamia cycads and their specialist thrips pollinators.

    Science.gov (United States)

    Brookes, D R; Hereward, J P; Terry, L I; Walter, G H

    2015-12-01

    Obligate pollination mutualisms are rare and few have been investigated deeply. This paper focuses on one such mutualism involving thrips in the genus Cycadothrips that pollinate cycads in the genus Macrozamia. Both represent old lineages relative to insects and plants generally, are endemic to Australia, and are mutually co-dependent. The phylogenetic analyses presented here demonstrate that the pollinator is much more diverse than previously considered, with each pollinator lineage being extremely specific to between one and three host species where these latter share part of their distribution. The new species diversity we demonstrate in Cycadothrips all presently falls under the species name C. chadwicki, and these different lineages diversified during two periods. An older divergence, beginning 7.3Mya (4.4-11.1, 95% HPD), resulted in three major lineages, and then further diversification within each of these three lineages took place at most 1.1Mya (0.6-1.8, 95% HPD). These divergence estimates correspond to times when aridification was increasing in Australia, suggesting that population fragmentation following climatic change has played a significant role in the evolutionary history of Cycadothrips and Macrozamia. This means that co-diversification of the host and pollinator in allopatry appears to be the dominant process affecting species diversity. Host switching is also clearly evident in the discrepancy between the divergence times of the C. chadwicki lineage and C. albrechti, about 10.8Mya (6.0-17.1, 95% HPD), and their hosts, at about 1.1Mya (0.2-3.4Mya, 95% HPD), in that the pollinator split pre-dates the origin of the associated host species of each. These results add to the body of evidence that the evolutionary processes important in obligate pollinator mutualisms are more varied than previously assumed. Copyright © 2015 Elsevier Inc. All rights reserved.

  18. The Xanton-Chassenon II wind farm site - Non technical summary of the impact study, opinion of the environmental authority, public inquiry, additional impact study on avifauna after the opinion of the environmental authority, analysis of chiropterans activity in altitude

    International Nuclear Information System (INIS)

    2013-01-01

    A first document aims at public information and consultation by proposing a synthetic overview of the wind farm project. It presents the involved actors, the methodology adopted to select the site and the project scenario. It describes the actual project (wind turbines, agreement, exploitation duration, compliance with urban planning documents), gives an overview of the results of the impact study (social-economic impacts, impacts on the environment, on landscape and heritage, on acoustics, on health, climate and air quality, and soil and water). It indicates measures aimed at avoiding, reducing or compensating drawbacks. The official opinion of the environmental authority is then provided. The public enquiry process is reported, with a presentation of various studied impacts, an overview of public opinion expressions and of counter-proposals. A detailed additional impact study regarding avifauna is provided as an answer to the opinion of the environmental authority. Another opinion of the environmental authority on the exploitation authorisation request is provided. The last report contains an analysis of chiropterans activity in altitude (methodology, ecological diagnosis)

  19. Pollination deficit in open-field tomato crops (Solanum lycopersicum L., Solanaceae in Rio de Janeiro state, Southeast Brazil

    Directory of Open Access Journals (Sweden)

    Mariana Scaramussa Deprá

    2014-02-01

    Full Text Available More than 70% of world’s crops benefit from biotic pollination, and bees are their main pollinators. Despite the fact that some of these insects have been broadly studied, understanding the interactions between plant crops and their pollinators with a local scale approach is necessary when aiming to apply proper protective and management measures to pollinators and their respective crops. In this context, we analyzed the pollination status of open-field tomato crops (Solanum lycopersicum L., regarding fruit-set, visitation rate and the quality of fruits. We recorded the formation of fruits through spontaneous self-pollination and open-pollination, and the occurrence of pollinators in 24 areas of open-field tomato crops. We performed experiments of apomixis, spontaneous self-pollination, manual cross pollination and supplemental cross pollination (simulating the pollinator behavior in a greenhouse. The fruit quality was evaluated according to circumference, weight, volume and number of seeds. Higher production of fruits after open-pollination compared to spontaneous self-pollination indicates the importance of pollinators to increment productivity of S. lycopersicum in the study area. The circumference and the number of seeds from tomatoes of the greenhouse plantation did not differ between spontaneous self-pollination and the manual cross pollination. In the open-field crops the number of seeds was higher for fruits resulting from open-pollination. Our results indicate that the importance of bees is mainly related to the increase in fruit production, thus incrementing the productivity of tomato crops.

  20. Diagnosis of directed pollination services in apple orchards in Brazil

    Directory of Open Access Journals (Sweden)

    Joatan Machado da Rosa

    2018-04-01

    Full Text Available Abstract The pollination services performed by Apis mellifera are essential for the high-quality apple production. The aim of this study was to obtain information about the pollination services used in the municipalities of Vacaria-RS e São Joaquim-SC, the main apple-producing regions in Brazil. Semi-structured interviews were conducted with apple growers and technicians responsible for the orchards during 2013 and 2015. The obtained information was: a cropping systems; b use of pollination services; c number of hives per hectare during flowering; d renting value of hives; e mortality of colonies; f agrochemicals used on flowering; g presence of native bees on flowering. In Vacaria and São Joaquim, respectively, 70% and 68.6% of the apple growers use the integrated apple production as their production model. The directed pollination is used by 100% and 90.0% of respondents respectively, from which, 80% and 47.1% opt for the hive rent. On average, three hives were used per hectare in both regions. The average cost is U$ 17.52 and U$ 17.74 per hive, respectively. During the flowering period, insecticides and fungicides are used by 100% and 97.2% of the apple growers. The highest mean percentage of mortality of colonies during flowering was reported in Vacaria, 11.8%. Native bees are often found in apple flowers. The development of management strategies for the conservation of domestic and wild pollinators is essential.

  1. Application of Proteomics to the Study of Pollination Drops

    Directory of Open Access Journals (Sweden)

    Natalie Prior

    2013-04-01

    Full Text Available Premise of the study: Pollination drops are a formative component in gymnosperm pollen-ovule interactions. Proteomics offers a direct method for the discovery of proteins associated with this early stage of sexual reproduction. Methods: Pollination drops were sampled from eight gymnosperm species: Chamaecyparis lawsoniana (Port Orford cedar, Ephedra monosperma, Ginkgo biloba, Juniperus oxycedrus (prickly juniper, Larix ×marschlinsii, Pseudotsuga menziesii (Douglas-fir, Taxus ×media, and Welwitschia mirabilis. Drops were collected by micropipette using techniques focused on preventing sample contamination. Drop proteins were separated using both gel and gel-free methods. Tandem mass spectrometric methods were used including a triple quadrupole and an Orbitrap. Results: Proteins are present in all pollination drops. Consistency in the protein complement over time was shown in L. ×marschlinsii. Representative mass spectra from W. mirabilis chitinase peptide and E. monosperma serine carboxypeptidase peptide demonstrated high quality results. We provide a summary of gymnosperm pollination drop proteins that have been discovered to date via proteomics. Discussion: Using proteomic methods, a dozen classes of proteins have been identified to date. Proteomics presents a way forward in deepening our understanding of the biological function of pollination drops.

  2. Application of an Additional Controllable Load (ACL) with chopper connected to the Direct Current Link (DCL) of an autonomous Wind Energy Power System (WEPS)

    Science.gov (United States)

    Smets, A. H. A. M.

    1984-05-01

    An ACL consisting of a (fast) thyristor chopper with indirect commutation and loaded by a resistor is described. The ACL provides a reduction of grid voltage distortions, reactive power of the WEPS diesel generator, and the amplitude of higher harmonic currents in the autonomous grid. Ripple currents in the DCL are limited by the connection between chopper and DCL. An additional choke is connected in series with the existing choke in the DCL. Chopper and a smoothing capacitor were connected with one pole to the junction of both chokes. A resonance circuit is formed using chokes and capacitor. The resonance frequency is chosen such that no impermissible oscillations occur in the DCL. Equations to calculate components of the DCL and chopper for their dimensioning were derived. In an experimental set-up consisting of a part of the WEPS, measurements were carried out.

  3. Commercial bumblebee hives to assess an anthropogenic environment for pollinator support: a case study in the region of Ghent (Belgium).

    Science.gov (United States)

    Parmentier, Laurian; Meeus, Ivan; Cheroutre, Lore; Mommaerts, Veerle; Louwye, Stephen; Smagghe, Guy

    2014-04-01

    Anthropogenic changes of the environment influence the distribution and abundance of pollinators such as bumblebees and have been proposed as one of the main causes in their worldwide decline. In order to evaluate the impact of expanding anthropogenic landscapes on supporting pollinator potential, reliable tools are needed. Bombus terrestris is one of the most abundant bumblebee species in Europe, and these bumblebees are known as generalist pollinators of not only wild flowers in nature but also of crops in agriculture. For more than two decades, these bumblebees have been commercially mass reared for biological pollination in greenhouses. In this project, we placed commercial hives of the bumblebee B. terrestris containing one queen and 40 workers, in three different locations in the region of Ghent (Belgium), and the performance of these hives was followed during a 4-week period in spring 2012. In parallel, we determined the floral richness and diversity index in the chosen study sites. The sites consisted of a rich urban environment with patchy green areas opposed to an urban environment with poor landscape metrics; a third rural study site showed average positive landscape metrics. The results demonstrated that the hive biomass and numbers of workers increased significantly in the rich compared to the poor environment, providing a mechanism to discriminate between study sites. In addition, the bumblebee-collected pollen showed that the flowering plants Salix spp. and Rosaceae/Prunus spp. are dominant food sources in all anthropogenic environments during early spring. Finally, the results are discussed in relation to the optimization of the experimental setup and to the use of commercial bumblebee hives in assessing local pollinator support within any given environment.

  4. Potential pollinators and robbers: a study of the floral visitors of Heliconia angusta (Heliconiaceae and their behaviour

    Directory of Open Access Journals (Sweden)

    Hensen, Isabell

    2011-05-01

    Full Text Available Floral syndromes are traditionally thought to be associated with particular pollinator groups. Ornithophilous flowers tend to have traits that facilitate bird pollination such as having long, narrow, tubular corollas, often vivid coloration and diluted, sucrose-rich nectar. However, recent studies have shown that flowers attract a broader spectrum of visitors than might be expected. Furthermore, the classification of floral visitors as ‘robbers’ or ‘pollinators’ often is not as simple as it seems, as pollinators can at times act as robbers and vice versa. We studied the species composition, behaviour and ecology of floral visitors, including potential pollinators and robbers, of Heliconia angusta (Heliconiaceae, an endemic understorey herb of the Atlantic Rainforest of Brazil. In addition, the impact of the plant inflorescence attractiveness and of weather and light conditions on visitor abundance and frequency was investigated. Flower visitors were found to be scarce with a total of only 151 visits being observed during 120 h of field observations. A stingless bee species (Trigona sp. appeared to be the most abundant visitor to the ornithophilous flowers of H. angusta, along with four different species of hummingbirds and two species of butterflies. We consider Trigona sp. rather as pollen robber, but which still has the potential to be a secondary pollinator, whereas the hummingbirds were the principle legitimate visitors. Most flower visitors were recorded between 9.00 am and 1.00 pm with a higher number visiting under semi-shaded conditions than in full shade. Hummingbird numbers increased with flower abundance while the other visitor group numbers were not affected.

  5. Environmental effects of fenitrothion use in forestry: impacts on insect pollinators, songbirds & aquatic organisms

    National Research Council Canada - National Science Library

    Ernst, W. R; Pearce, P. A; Pollock, T. L

    1989-01-01

    The Team focused on insect pollinators and pollination, forest songbirds, and aquatic organisms because of a judgement that most well documented negative effects of fenitrothion spraying are in those...

  6. Caffeine in floral nectar enhances a pollinator's memory of reward.

    Science.gov (United States)

    Wright, G A; Baker, D D; Palmer, M J; Stabler, D; Mustard, J A; Power, E F; Borland, A M; Stevenson, P C

    2013-03-08

    Plant defense compounds occur in floral nectar, but their ecological role is not well understood. We provide evidence that plant compounds pharmacologically alter pollinator behavior by enhancing their memory of reward. Honeybees rewarded with caffeine, which occurs naturally in nectar of Coffea and Citrus species, were three times as likely to remember a learned floral scent as were honeybees rewarded with sucrose alone. Caffeine potentiated responses of mushroom body neurons involved in olfactory learning and memory by acting as an adenosine receptor antagonist. Caffeine concentrations in nectar did not exceed the bees' bitter taste threshold, implying that pollinators impose selection for nectar that is pharmacologically active but not repellent. By using a drug to enhance memories of reward, plants secure pollinator fidelity and improve reproductive success.

  7. Floral diversity and pollination strategies of three rheophytic Schismatoglottideae (Araceae).

    Science.gov (United States)

    Low, S L; Wong, S Y; Ooi, I H; Hesse, M; Städler, Y; Schönenberger, J; Boyce, P C

    2016-01-01

    Homoplastic evolution of 'unique' morphological characteristics in the Schismatoglottideae - many previously used to define genera - prompted this study to compare morphology and function in connection with pollination biology for Aridarum nicolsonii, Phymatarum borneense and Schottarum sarikeense. Aridarum nicolsonii and P. borneense extrude pollen through a pair of horned thecae while S. sarikeense sheds pollen through a pair of pores on the thecae. Floral traits of spathe constriction, presence and movement of sterile structures on the spadix, the comparable role of horned thecae and thecae pores, the presence of stamen-associated calcium oxalate packages, and the timing of odour emission are discussed in the context of their roles in pollinator management. Pollinators for all investigated species were determined to be species of Colocasiomyia (Diptera: Drosophilidae). © 2015 German Botanical Society and The Royal Botanical Society of the Netherlands.

  8. Microclimate and Individual Variation in Pollinators: Flowering Plants are More than Their Flowers

    OpenAIRE

    Herrera, Carlos M.

    1995-01-01

    Variation in pollinator composition at the individual plant level is an important prerequisite for plant specialization on pollinators that does not seem to have been investigated previously. I studied variation in pollinator composition in a southeastern Spanish population of the insect-pollinated shrub Lavandula latifolia (Labiatae) and examined its correlates, with particular reference to the distinction between factors intrinsic (flower morphology, nectar standing crop, size of floral dis...

  9. Contribution of insect pollinators to crop yield and quality varies with agricultural intensification

    Directory of Open Access Journals (Sweden)

    Ignasi Bartomeus

    2014-03-01

    Full Text Available Background. Up to 75% of crop species benefit at least to some degree from animal pollination for fruit or seed set and yield. However, basic information on the level of pollinator dependence and pollinator contribution to yield is lacking for many crops. Even less is known about how insect pollination affects crop quality. Given that habitat loss and agricultural intensification are known to decrease pollinator richness and abundance, there is a need to assess the consequences for different components of crop production.Methods. We used pollination exclusion on flowers or inflorescences on a whole plant basis to assess the contribution of insect pollination to crop yield and quality in four flowering crops (spring oilseed rape, field bean, strawberry, and buckwheat located in four regions of Europe. For each crop, we recorded abundance and species richness of flower visiting insects in ten fields located along a gradient from simple to heterogeneous landscapes.Results. Insect pollination enhanced average crop yield between 18 and 71% depending on the crop. Yield quality was also enhanced in most crops. For instance, oilseed rape had higher oil and lower chlorophyll contents when adequately pollinated, the proportion of empty seeds decreased in buckwheat, and strawberries’ commercial grade improved; however, we did not find higher nitrogen content in open pollinated field beans. Complex landscapes had a higher overall species richness of wild pollinators across crops, but visitation rates were only higher in complex landscapes for some crops. On the contrary, the overall yield was consistently enhanced by higher visitation rates, but not by higher pollinator richness.Discussion. For the four crops in this study, there is clear benefit delivered by pollinators on yield quantity and/or quality, but it is not maximized under current agricultural intensification. Honeybees, the most abundant pollinator, might partially compensate the loss of wild

  10. More than euglossines: the diverse pollinators and floral scents of Zygopetalinae orchids.

    Science.gov (United States)

    Nunes, Carlos E P; Wolowski, Marina; Pansarin, Emerson Ricardo; Gerlach, Günter; Aximoff, Izar; Vereecken, Nicolas J; Salvador, Marcos José; Sazima, Marlies

    2017-10-13

    Floral volatile organic compounds (VOCs) play important roles in plant-pollinator interactions. We investigated the reproductive ecology and floral VOCs of Zygopetalinae orchids to understand the relationship between floral scents and pollinators. We performed focal observations, phenological censuses and breeding system experiments in eight species in southeast Brazil. Floral scents were collected and analysed using SPME/GC-MS. We performed multivariate analyses to group species according to affinities of their VOCs and define compounds associated to each plant. Dichaea cogniauxiana was pollinated by weevils which use their developing ovules, while D. pendula was pollinated by the same weevils and perfume-collecting male euglossine bees. The other species were deceit-pollinated by bees. Zygopetalum crinitum was pollinated by carpenter bees, while W. warreana, Z. mackayi and Z. maxillare were bumblebee-pollinated. The latter was also pollinated by Centris confusa. Breeding system varied widely with no association to any pollinator group. Most VOCs are common to other floral scents. Zygopetalum crinitum presented an exclusive blend of VOCs, mainly composed of benzenoids. The scents of Pabstia jugosa, Promenaea xanthina and the Zygopetalum spp. were similar. The bumblebee-pollinated species have flowering periods partially overlapped, thus neither phenology nor pollinators constitute hybridization barriers among these species. Euglossines are not the only pollinators of Zygopetalinae. Different VOCs, size and lifespan of flowers are associated with distinct pollinators. A distinctive VOC bouquet may determine specialisation in carpenter bees or male euglossines within bee-pollinated flowers. Finally, visitation of deceit-pollinated flowers by perfume-collecting euglossines allows us to hypothesise how pollination by this group of bees had evolved.

  11. Notes on the flowering and pollination of the endemic grassland Aloe reitzii var. reitzii (Asphodelaceae

    Directory of Open Access Journals (Sweden)

    Craig T. Symes

    2017-08-01

    Conclusion: Because birds are important pollinators for many Aloe species, it is assumed that the bird species detected visiting A. reitzii var. reitzii are similarly important pollinators. At least 10 invertebrate species and sengi (Elephantulus sp. were also recorded as visitors to flowers, but they may be less important pollinators than specialist and generalist avian nectarivores. This study provides further insight into the pollination biology of a diverse, and ecologically important, succulent genus in Africa.

  12. Time-calibrated phylogeny of the woody Australian genus Hakea (Proteaceae) supports multiple origins of insect-pollination among bird-pollinated ancestors.

    Science.gov (United States)

    Mast, Austin R; Milton, Ethan F; Jones, Eric H; Barker, Robyn M; Barker, William R; Weston, Peter H

    2012-03-01

    A past study based on morphological data alone showed that the means by which plants of the Australian genus Hakea reduce florivory is related to the evolution of bird pollination. For example, bird pollination was shown to have arisen only in insect-pollinated lineages that already produced greater amounts of floral cyanide, a feature that reduces florivory. We examine a central conclusion of that study, and a common assumption in the literature, that bird pollination arose in insect-pollinated lineages, rather than the reverse. We combined morphological and DNA data to infer the phylogeny and age of the Australian genus Hakea, using 9.2 kilobases of plastid and nuclear DNA and 46 morphological characters from a taxonomically even sampling of 55 of the 149 species. Hakea is rooted confidently in a position that has not been suggested before. The phylogeny implies that bird pollination is primitive in Hakea and that multiple shifts to insect pollination have occurred. The unexpectedly young age of Hakea (a crown age of ca. 10 Ma) makes it coincident with its primary bird pollinators (honeyeaters) throughout its history. Our study demonstrates that Hakea is an exception to the more commonly described shift from insect to bird pollination. However, we note that only one previous phylogenetic study involved Australian plants and their honeyeater pollinators and that our finding might prove to be more common on that continent.

  13. Illinois Wind Workers Group

    Energy Technology Data Exchange (ETDEWEB)

    David G. Loomis

    2012-05-28

    The Illinois Wind Working Group (IWWG) was founded in 2006 with about 15 members. It has grown to over 200 members today representing all aspects of the wind industry across the State of Illinois. In 2008, the IWWG developed a strategic plan to give direction to the group and its activities. The strategic plan identifies ways to address critical market barriers to the further penetration of wind. The key to addressing these market barriers is public education and outreach. Since Illinois has a restructured electricity market, utilities no longer have a strong control over the addition of new capacity within the state. Instead, market acceptance depends on willing landowners to lease land and willing county officials to site wind farms. Many times these groups are uninformed about the benefits of wind energy and unfamiliar with the process. Therefore, many of the project objectives focus on conferences, forum, databases and research that will allow these stakeholders to make well-educated decisions.

  14. Pollinator networks, alien species and the conservation of rare plants: Trinia glauca as a case study

    NARCIS (Netherlands)

    Carvalheiro, L.G.; Barbosa, E.R.; Memmott, J.

    2008-01-01

    1. Despite the essential role of pollination in the maintenance of many rare plant species, conservation management plans rarely consider the service of pollination. 2. This study identifies the main pollinators of a rare English plant species, Trinia glauca (Apiaceae), and provides recommendations

  15. Repeated evolution of vertebrate pollination syndromes in a recently diverged Andean plant clade.

    Science.gov (United States)

    Lagomarsino, Laura P; Forrestel, Elisabeth J; Muchhala, Nathan; Davis, Charles C

    2017-08-01

    Although specialized interactions, including those involving plants and their pollinators, are often invoked to explain high species diversity, they are rarely explored at macroevolutionary scales. We investigate the dynamic evolution of hummingbird and bat pollination syndromes in the centropogonid clade (Lobelioideae: Campanulaceae), an Andean-centered group of ∼550 angiosperm species. We demonstrate that flowers hypothesized to be adapted to different pollinators based on flower color fall into distinct regions of morphospace, and this is validated by morphology of species with known pollinators. This supports the existence of pollination syndromes in the centropogonids, an idea corroborated by ecological studies. We further demonstrate that hummingbird pollination is ancestral, and that bat pollination has evolved ∼13 times independently, with ∼11 reversals. This convergence is associated with correlated evolution of floral traits within selective regimes corresponding to pollination syndrome. Collectively, our results suggest that floral morphological diversity is extremely labile, likely resulting from selection imposed by pollinators. Finally, even though this clade's rapid diversification is partially attributed to their association with vertebrate pollinators, we detect no difference in diversification rates between hummingbird- and bat-pollinated lineages. Our study demonstrates the utility of pollination syndromes as a proxy for ecological relationships in macroevolutionary studies of certain species-rich clades. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.

  16. Re-establishing pollinator habitat on mined lands using the forestry reclamation approach

    Science.gov (United States)

    Tammy Horn; Patrick Angel; Carl Zipper; Michael Ulyshen; Michael French; Jim Burger; Mary Beth. Adams

    2017-01-01

    Pollinators are animals that play an essential role in the reproduction of many plants by transferring genetic material, in the form of pollen, from male to female flower parts. Because pollinator communities are under threat both in the US and worldwide, there is great interest in incorporating the needs of pollinators into habitat restoration plans. Forests provide...

  17. Floral acoustics : conspicuous echoes of a dish-shaped leaf attract bat pollinators

    NARCIS (Netherlands)

    Simon, Ralph; Holderied, Marc W; Koch, Corinna U; von Helversen, Otto

    2011-01-01

    The visual splendor of many diurnal flowers serves to attract visually guided pollinators such as bees and birds, but it remains to be seen whether bat-pollinated flowers have evolved analogous echo-acoustic signals to lure their echolocating pollinators. Here, we demonstrate how an unusual

  18. Pollination ecology in the 21st Century: Key questions for future research

    Directory of Open Access Journals (Sweden)

    Jane C. Stout

    2011-03-01

    Full Text Available To inspire new ideas in research on pollination ecology, we list the most important unanswered questions in the field. This list was drawn up by contacting 170 scientists from different areas of pollination ecology and asking them to contribute their opinion on the greatest knowledge gaps that need to be addressed. Almost 40% of them took part in our email poll and we received more than 650 questions and comments, which we classified into different categories representing various aspects of pollination research. The original questions were merged and synthesised, and a final vote and ranking led to the resultant list. The categories cover plant sexual reproduction, pollen and stigma biology, abiotic pollination, evolution of animal-mediated pollination, interactions of pollinators and floral antagonists, pollinator behaviour, taxonomy, plant-pollinator assemblages, geographical trends in diversity, drivers of pollinator loss, ecosystem services, management of pollination, and conservation issues such as the implementation of pollinator conservation. We focused on questions that were of a broad scope rather than case-specific; thus, addressing some questions may not be feasible within single research projects but constitute a general guide for future directions. With this compilation we hope to raise awareness of pollination-related topics not only among researchers but also among non-specialists including policy makers, funding agencies and the public at large.

  19. Development of a Pollination Service Measurement (PSM) method using potted plant phytometry.

    Science.gov (United States)

    Woodcock, Thomas S; Pekkola, Laura J; Dawson, Cara; Gadallah, Fawziah L; Kevan, Peter G

    2014-08-01

    The value of pollination to human society is not limited to agricultural production, but also in the sustainability of ecosystems and the services that they provide. Seed set can be used as a comparative measure of pollination effectiveness, with minimum variability expected when other resources are not limiting. Six species of self-incompatible fall asters (Symphyotrichum) were used to evaluate pollination service at 12 sites across a spectrum of expected levels of pollination. Seed set per inflorescence was generally lower at sites with lower pollinator numbers and diversity, although as expected pollinator assemblage characteristics were highly variable within and between sites. However, rankings of sites showed consistency of response across phytometer species and between years; the summed ranks across multiple species appears to have as the greatest value in Pollination Service Measurement (PSM). Abundance, richness, and Shannon diversity of pollinator assemblages were highly autocorrelated and showed variable relationships with seed set depending on plant species and temporal scale of pollinator assemblage assessment. Use of seed set to directly measure pollination service at a site was consistent and cost effective when compared to less certain and more labour-intensive methods of pollinator collection and identification, and shows promise for implementation in pollination monitoring and bioassessment practices.

  20. The Economic Value of the Pollination Service, a Review Across Scales

    NARCIS (Netherlands)

    Hein, L.G.

    2009-01-01

    Pollination is an ecosystem service that is essential to support the production of a wide range of crops. The service is increasingly under threat, as a consequence of among others habitat loss of pollinators and increasing use of pesticides. In order to support maintaining the pollination service

  1. Effect of Ratooning on the Yield of Hybrid and Open-Pollinated ...

    African Journals Online (AJOL)

    An experiment was done at Chiredzi Research Station, Zimbabwe, to establish the possibility of producing ratoon crops from four cabbage (Brassica oleraceae var capitata) cultivars: Sugarloaf (open-pollinated), Drumhead (open-pollinated), Goldern Acre (open-pollinated) and Exotic (F1 hybrid). There were significant ...

  2. Hummingbird pollination and the diversification of angiosperms: an old and successful association in Gesneriaceae.

    Science.gov (United States)

    Serrano-Serrano, Martha Liliana; Rolland, Jonathan; Clark, John L; Salamin, Nicolas; Perret, Mathieu

    2017-04-12

    The effects of specific functional groups of pollinators in the diversification of angiosperms are still to be elucidated. We investigated whether the pollination shifts or the specific association with hummingbirds affected the diversification of a highly diverse angiosperm lineage in the Neotropics. We reconstructed a phylogeny of 583 species from the Gesneriaceae family and detected diversification shifts through time, inferred the timing and amount of transitions among pollinator functional groups, and tested the association between hummingbird pollination and speciation and extinction rates. We identified a high frequency of pollinator transitions, including reversals to insect pollination. Diversification rates of the group increased through time since 25 Ma, coinciding with the evolution of hummingbird-adapted flowers and the arrival of hummingbirds in South America. We showed that plants pollinated by hummingbirds have a twofold higher speciation rate compared with plants pollinated by insects, and that transitions among functional groups of pollinators had little impact on the diversification process. We demonstrated that floral specialization on hummingbirds for pollination has triggered rapid diversification in the Gesneriaceae family since the Early Miocene, and that it represents one of the oldest identified plant-hummingbird associations. Biotic drivers of plant diversification in the Neotropics could be more related to this specific type of pollinator (hummingbirds) than to shifts among different functional groups of pollinators. © 2017 The Author(s).

  3. Auxin is required for pollination-induced ovary growth in Dendrobium orchids

    NARCIS (Netherlands)

    Ketsa, S.; Wisutiamonkul, A.; Doorn, van W.G.

    2006-01-01

    In Dendrobium and other orchids the ovule becomes mature long after pollination, whereas the ovary starts growing within two days of pollination. The signalling pathway that induces rapid ovary growth after pollination has remained elusive. We placed the auxin antagonist ¿-(p-chlorophenoxy)

  4. Indirect Effects of Field Management on Pollination Service and Seed Set in Hybrid Onion Seed Production.

    Science.gov (United States)

    Gillespie, Sandra; Long, Rachael; Williams, Neal

    2015-12-01

    Pollination in crops, as in native ecosystems, is a stepwise process that can be disrupted at any stage. Healthy pollinator populations are critical for adequate visitation, but pollination still might fail if crop management interferes with the attraction and retention of pollinators. Farmers must balance the direct benefits of applying insecticide and managing irrigation rates against their potential to indirectly interfere with the pollination process. We investigated these issues in hybrid onion seed production, where previous research has shown that high insecticide use reduces pollinator attraction. We conducted field surveys of soil moisture, nectar production, pollinator visitation, pollen-stigma interactions, and seed set at multiple commercial fields across 2 yr. We then examined how management actions, such as irrigation rate (approximated by soil moisture), or insecticide use could affect the pollination process. Onions produced maximum nectar at intermediate soil moisture, and high nectar production attracted more pollinators. Insecticide use weakly affected pollinator visitation, but when applied close to bloom reduced pollen germination and pollen tube growth. Ultimately, neither soil moisture nor insecticide use directly affected seed set, but the high correlation between pollinator visitation and seed set suggests that crop management will ultimately affect yields via indirect effects on the pollination process. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  5. A scientific note on the use of stingless bees for commercial pollination in enclosures

    NARCIS (Netherlands)

    Slaa, E.J.; Sanchez, Luis Alejandro; Sandi, Miriam; Salazar, William

    1999-01-01

    Stingless bees are considered to be very important pollinators in the tropics, and they are known to effectively pollinate at least 9 crops [1]. Nevertheless, they are seldomly used for commercial pollination. To our knowledge, only one study has been published using stingless bees for crop

  6. Integrating Studies on Plant-Pollinator and Plant-Herbivore Interactions

    NARCIS (Netherlands)

    Lucas-Barbosa, Dani

    2016-01-01

    Research on herbivore-induced plant defence and research on pollination ecology have had a long history of separation. Plant reproduction of most angiosperm species is mediated by pollinators, and the effects of herbivore-induced plant defences on pollinator behaviour have been largely neglected.

  7. western honey bee management for crop pollination abstract résumé

    African Journals Online (AJOL)

    ACSS

    2018-02-09

    Feb 9, 2018 ... This literature review seeks to provide an outlook of the use of Western honeybee for crop pollination around the world. It was prepared by collecting information on the use of managed honey bees, Apis mellifera in crop pollination from different sources. To address pollination deficits, farmers around the ...

  8. Predicting plant attractiveness to pollinators with passive crowdsourcing.

    Science.gov (United States)

    Bahlai, Christie A; Landis, Douglas A

    2016-06-01

    Global concern regarding pollinator decline has intensified interest in enhancing pollinator resources in managed landscapes. These efforts frequently emphasize restoration or planting of flowering plants to provide pollen and nectar resources that are highly attractive to the desired pollinators. However, determining exactly which plant species should be used to enhance a landscape is difficult. Empirical screening of plants for such purposes is logistically daunting, but could be streamlined by crowdsourcing data to create lists of plants most probable to attract the desired pollinator taxa. People frequently photograph plants in bloom and the Internet has become a vast repository of such images. A proportion of these images also capture floral visitation by arthropods. Here, we test the hypothesis that the abundance of floral images containing identifiable pollinator and other beneficial insects is positively associated with the observed attractiveness of the same species in controlled field trials from previously published studies. We used Google Image searches to determine the correlation of pollinator visitation captured by photographs on the Internet relative to the attractiveness of the same species in common-garden field trials for 43 plant species. From the first 30 photographs, which successfully identified the plant, we recorded the number of Apis (managed honeybees), non-Apis (exclusively wild bees) and the number of bee-mimicking syrphid flies. We used these observations from search hits as well as bloom period (BP) as predictor variables in Generalized Linear Models (GLMs) for field-observed abundances of each of these groups. We found that non-Apis bees observed in controlled field trials were positively associated with observations of these taxa in Google Image searches (pseudo-R (2) of 0.668). Syrphid fly observations in the field were also associated with the frequency they were observed in images, but this relationship was weak. Apis bee

  9. Pollinator-mediated selection on nectary depth in Urophysa (Ranunculaceae

    Directory of Open Access Journals (Sweden)

    Li Sun

    2016-04-01

    Full Text Available Pollinator-mediated selection has been considered to be one of major factors that shapes the evolution of flowers by matching flowers to their pollinators on traits associated with attraction of pollinators or mechanical fit. The match between nectary depth, which means the length of the tubular structure formed in many plant species to hide the nectary and store nectar, and the mouthparts length of its major nectar-foraging pollinators has been repeatedly demonstrated as an example, because this trait have shown a positive relationship with pollen removal and deposition in experimental manipulations in many synpetalous plants and orchid family. However, it remains unclear how pollinator-mediated selection affects the evolution of nectary depth in choripetalous and actinomorphic flowers, such as most flowers in Ranunculaceae. Here we investigated floral characteristics and pollinators in Urophysa rockii Ulbr. and U. henryi (Oliv. Ulbr., as they are quite the same in habitat, anthesis and morphological characteristics except for nectary depth. Both of these species have flat white sepals and yellow petals each has a spatial structure at the base that contains nectar, but the nectary depth of U. rockii is deeper than that of U. henryi, for the former petals are shortly spurred about 3-4mm in length while the latter are saccate. Meanwhile, the flowers of both species are most frequently visited by Apis cerana, the Chinese honey bee, and one or two species of hover fly, Syrphidae, but only A. cerana was able to forage nectar in U. rockii while all visitors can forage nectar in U. henryi. A. cerana always lands on the center of a flower and projects its proboscis into each petal when its thorax touches anthers and stigmas. The difference between two species is that U. rockii was visited by A. cerana with a higher frequency, longer visiting time per flower and more activities on flowers than U. henryi. Besides, the petal width and its nectary depth of

  10. Phylogeny of the pollinating yucca moths, with revision of Mexican species (Tegeticula and Parategeticula; Lepidoptera, Prodoxidae)

    Energy Technology Data Exchange (ETDEWEB)

    Pellmyr, Olof; Balcazar-Lara, Manuel; Segraves, Kari A.; Althoff, David M.; Littlefield, Rik J.

    2008-02-01

    ABSTRACT The yucca moths (Tegeticula and Parategeticula; Lepidoptera, Prodoxidae) are well-known for their obligate relationship as exclusive pollinators of yuccas. Revisionary work in recent years has revealed far higher species diversity than historically recognized, increasing the number of described species from four to 21. Based on field surveys in Mexico and examination of collections, we describe five additional species: T. californica Pellmyr sp. nov., T. tehuacana Pellmyr & Balcázar-Lara sp. nov., T. tambasi Pellmyr & Balcázar-Lara sp. nov., T. baja Pellmyr & Balcázar-Lara sp. nov., and P. californica Pellmyr & Balcázar-Lara sp. nov. Tegeticula treculeanella Pellmyr is identified as a junior synonym of T. mexicana Bastida. A diagnostic key to the adults of all species of the T. yuccasella complex is provided. A phylogeny based on a 2104-bp segment of mitochondrial DNA (mtDNA) in the cytochrome oxidase I and II region supported monophyly of the two pollinator genera, and strongly supported monophyly of the 17 recognized species of the T. yuccasella complex. Most relationships are well-supported, but some relationships within a recent and rapidly diversified group of 11 taxa are less robust, and in one case conflicts with a whole-genome data set (AFLP). The current mtDNA-based analyses, together with previously published AFLP data, provide a robust phylogenetic foundation for future studies of life history evolution and host interactions in one of the classical models of coevolution and obligate mutualism. ADDITIONAL KEY WORDS: mutualism, pollination, molecular phylogenetics, mitochondrial DNA

  11. Wind power

    International Nuclear Information System (INIS)

    Gipe, P.

    2007-01-01

    This book is a translation of the edition published in the USA under the title of ''wind power: renewable energy for home, farm and business''. In the wake of mass blackouts and energy crises, wind power remains a largely untapped resource of renewable energy. It is a booming worldwide industry whose technology, under the collective wing of aficionados like author Paul Gipe, is coming of age. Wind Power guides us through the emergent, sometimes daunting discourse on wind technology, giving frank explanations of how to use wind technology wisely and sound advice on how to avoid common mistakes. Since the mid-1970's, Paul Gipe has played a part in nearly every aspect of wind energy development from installing small turbines to promoting wind energy worldwide. As an American proponent of renewable energy, Gipe has earned the acclaim and respect of European energy specialists for years, but his arguments have often fallen on deaf ears at home. Today, the topic of wind power is cropping up everywhere from the beaches of Cape Cod to the Oregon-Washington border, and one wind turbine is capable of producing enough electricity per year to run 200 average American households. Now, Paul Gipe is back to shed light on this increasingly important energy source with a revised edition of Wind Power. Over the course of his career, Paul Gipe has been a proponent, participant, observer, and critic of the wind industry. His experience with wind has given rise to two previous books on the subject, Wind Energy Basics and Wind Power for Home and Business, which have sold over 50,000 copies. Wind Power for Home and Business has become a staple for both homeowners and professionals interested in the subject, and now, with energy prices soaring, interest in wind power is hitting an all-time high. With chapters on output and economics, Wind Power discloses how much you can expect from each method of wind technology, both in terms of energy and financial savings. The book updated models

  12. Wild pollinators enhance oilseed rape yield in small-holder farming systems in China.

    Science.gov (United States)

    Zou, Yi; Xiao, Haijun; Bianchi, Felix J J A; Jauker, Frank; Luo, Shudong; van der Werf, Wopke

    2017-02-21

    Insect pollinators play an important role in crop pollination, but the relative contribution of wild pollinators and honey bees to pollination is currently under debate. There is virtually no information available on the strength of pollination services and the identity of pollination service providers from Asian smallholder farming systems, where fields are small, and variation among fields is high. We established 18 winter oilseed rape (Brassica napus L.) fields along a large geographical gradient in Jiangxi province in China. In each field, oilseed rape plants were grown in closed cages that excluded pollinators and open cages that allowed pollinator access. The pollinator community was sampled by pan traps for the entire oilseed rape blooming period. Oilseed rape plants from which insect pollinators were excluded had on average 38% lower seed set, 17% lower fruit set and 12% lower yield per plant, but the seeds were 17% heavier, and the caged plants had 28% more flowers and 18% higher aboveground vegetative biomass than plants with pollinator access. Oilseed rape plants thus compensate for pollination deficit by producing heavier seeds and more flowers. Regression analysis indicated that local abundance and diversity of wild pollinators were positively associated with seed set and yield/straw ratio, while honey bee abundance was not related to yield parameters. Wild pollinator abundance and diversity contribute to oilseed rape yield by enhancing plant resource allocation to seeds rather than to above-ground biomass. This study highlights the importance of the conservation of wild pollinators to support oilseed rape production in small-holder farming systems in China.

  13. Pollination and plant resources change the nutritional quality of almonds for human health.

    Science.gov (United States)

    Brittain, Claire; Kremen, Claire; Garber, Andrea; Klein, Alexandra-Maria

    2014-01-01

    Insect-pollinated crops provide important nutrients for human health. Pollination, water and nutrients available to crops can influence yield, but it is not known if the nutritional value of the crop is also influenced. Almonds are an important source of critical nutrients for human health such as unsaturated fat and vitamin E. We manipulated the pollination of almond trees and the resources available to the trees, to investigate the impact on the nutritional composition of the crop. The pollination treatments were: (a) exclusion of pollinators to initiate self-pollination and (b) hand cross-pollination; the plant resource treatments were: (c) reduced water and (d) no fertilizer. In an orchard in northern California, trees were exposed to a single treatment or a combination of two (one pollination and one resource). Both the fat and vitamin E composition of the nuts were highly influenced by pollination. Lower proportions of oleic to linoleic acid, which are less desirable from both a health and commercial perspective, were produced by the self-pollinated trees. However, higher levels of vitamin E were found in the self-pollinated nuts. In some cases, combined changes in pollination and plant resources sharpened the pollination effects, even when plant resources were not influencing the nutrients as an individual treatment. This study highlights the importance of insects as providers of cross-pollination for fruit quality that can affect human health, and, for the first time, shows that other environmental factors can sharpen the effect of pollination. This contributes to an emerging field of research investigating the complexity of interactions of ecosystem services affecting the nutritional value and commercial quality of crops.

  14. Evolution of pollination niches and floral divergence in the generalist plant Erysimum mediohispanicum.

    Science.gov (United States)

    Gómez, J M; Muñoz-Pajares, A J; Abdelaziz, M; Lorite, J; Perfectti, F

    2014-01-01

    How generalist plants diverge in response to pollinator selection without becoming specialized is still unknown. This study explores this question, focusing on the evolution of the pollination system in the pollination generalist Erysimum mediohispanicum (Brassicaceae). Pollinator assemblages were surveyed from 2001 to 2010 in 48 geo-referenced populations covering the entire geographic distribution of E. mediohispanicum. Bipartite modularity, a complex network tool, was used to find the pollination niche of each population. Evolution of the pollination niches and the correlated evolution of floral traits and pollination niches were explored using within-species comparative analyses. Despite being generalists, the E. mediohispanicum populations studied can be classified into five pollination niches. The boundaries between niches were not sharp, the niches differing among them in the relative frequencies of the floral visitor functional groups. The absence of spatial autocorrelation and phylogenetic signal indicates that the niches were distributed in a phylogeographic mosaic. The ancestral E. mediohispanicum populations presumably belonged to the niche defined by a high number of beetle and ant visits. A correlated evolution was found between pollination niches and some floral traits, suggesting the existence of generalist pollination ecotypes. It is conjectured that the geographic variation in pollination niches has contributed to the observed floral divergence in E. mediohispanicum. The process mediating this floral divergence presumably has been adaptive wandering, but the adaptation to the local pollinator faunas has been not universal. The outcome is a landscape where a few populations locally adapted to their pollination environment (generalist pollination ecotypes) coexist with many populations where this local adaptation has failed and where the plant phenotype is not primarily shaped by pollinators.

  15. Pollination and plant resources change the nutritional quality of almonds for human health.

    Directory of Open Access Journals (Sweden)

    Claire Brittain

    Full Text Available Insect-pollinated crops provide important nutrients for human health. Pollination, water and nutrients available to crops can influence yield, but it is not known if the nutritional value of the crop is also influenced. Almonds are an important source of critical nutrients for human health such as unsaturated fat and vitamin E. We manipulated the pollination of almond trees and the resources available to the trees, to investigate the impact on the nutritional composition of the crop. The pollination treatments were: (a exclusion of pollinators to initiate self-pollination and (b hand cross-pollination; the plant resource treatments were: (c reduced water and (d no fertilizer. In an orchard in northern California, trees were exposed to a single treatment or a combination of two (one pollination and one resource. Both the fat and vitamin E composition of the nuts were highly influenced by pollination. Lower proportions of oleic to linoleic acid, which are less desirable from both a health and commercial perspective, were produced by the self-pollinated trees. However, higher levels of vitamin E were found in the self-pollinated nuts. In some cases, combined changes in pollination and plant resources sharpened the pollination effects, even when plant resources were not influencing the nutrients as an individual treatment. This study highlights the importance of insects as providers of cross-pollination for fruit quality that can affect human health, and, for the first time, shows that other environmental factors can sharpen the effect of pollination. This contributes to an emerging field of research investigating the complexity of interactions of ecosystem services affecting the nutritional value and commercial quality of crops.

  16. Management of arthropod pathogen vectors in North America: Minimizing adverse effects on pollinators

    Science.gov (United States)

    Ginsberg, Howard; Bargar, Timothy A.; Hladik, Michelle L.; Lubelczyk, Charles

    2017-01-01

    Tick and mosquito management is important to public health protection. At the same time, growing concerns about declines of pollinator species raise the question of whether vector control practices might affect pollinator populations. We report the results of a task force of the North American Pollinator Protection Campaign (NAPPC) that examined potential effects of vector management practices on pollinators, and how these programs could be adjusted to minimize negative effects on pollinating species. The main types of vector control practices that might affect pollinators are landscape manipulation, biocontrol, and pesticide applications. Some current practices already minimize effects of vector control on pollinators (e.g., short-lived pesticides and application-targeting technologies). Nontarget effects can be further diminished by taking pollinator protection into account in the planning stages of vector management programs. Effects of vector control on pollinator species often depend on specific local conditions (e.g., proximity of locations with abundant vectors to concentrations of floral resources), so planning is most effective when it includes collaborations of local vector management professionals with local experts on pollinators. Interventions can then be designed to avoid pollinators (e.g., targeting applications to avoid blooming times and pollinator nesting habitats), while still optimizing public health protection. Research on efficient targeting of interventions, and on effects on pollinators of emerging technologies, will help mitigate potential deleterious effects on pollinators in future management programs. In particular, models that can predict effects of integrated pest management on vector-borne pathogen transmission, along with effects on pollinator populations, would be useful for collaborative decision-making.

  17. Investigating plant–pollinator relationships in the Aegean: the approaches of the project POL-AEGIS (The pollinators of the Aegean archipelago: diversity and threats)

    OpenAIRE

    Petanidou, Theodora; Ståhls, Gunilla; Vujić, Ante; Olesen, Jens M.; Rojo Velasco, Santos; Thrasyvoulou, Andreas; Sgardelis, Stefanos; Kallimanis, Athanasios S.; Kokkini, Stella; Tscheulin, Thomas

    2013-01-01

    Worldwide, there is a well-documented crisis for bees and other pollinators which represent a fundamental biotic capital for wild life conservation, ecosystem function, and crop production. Among all pollinators of the world, bees (Hymenoptera: Apoidea) constitute the major group in species number and importance, followed by hover flies (Diptera: Syrphidae). The Aegean constitutes one of the world’s hotspots for wild bee and other pollinator diversity including flies (mainly hover flies and b...

  18. Blueberry pollination in southern Brazil and their influence on fruit quality

    Directory of Open Access Journals (Sweden)

    Tiago Madruga Telesca da Silveira

    2011-03-01

    Full Text Available Blueberry (Vaccinium ashei is a relatively new crop in cultivation under Southern Brazil conditions. The first collection introduced in the area was formed by rabbiteye cultivars which need insect pollinators and also pollinizers. The aim of this work was to observe if there were differences between pollinizers on fruit quality of the commercial cultivar and also to observe the most effective and frequent insect pollinators, under natural conditions. It was concluded that pollen source has an effect on quality of blueberry fruits. Bumblebees are the most efficient pollinators; however the species found in southern Brazil are different from the ones mentioned in the U.S. literature.

  19. Plant--Pollinator Interactions: A Rich Area for Study.

    Science.gov (United States)

    Aston, T. J.

    1987-01-01

    Outlines an adaptive framework for the study of plants and their pollinators in which both partners in the ecological relationship are seen as maximizing fitness through efficient use of the other as a resource. Suggests experimental projects to examine the validity of these assumptions giving an evolutionary emphasis. (Author/CW)

  20. Attracting pollinators in atemoya: commercial lures act synergistically when combined

    Science.gov (United States)

    Atemoya and other Annona species are delicious tropical and subtropical fruits. However, these plants tend to have low fruit-set due to inadequate pollination by small beetles, especially Nitidulidae. We established traps with two commercially available nitidulid lures (dusky sap beetle lure and dat...

  1. The hymenopterous pollinators of Himalayan foot hills of Pakistan ...

    African Journals Online (AJOL)

    Studies were undertaken to explore the diversity of hymenopterans pollinators from a diverse agroecosystems of Himalayan foot hills comprising the orchards of pome and stone fruits at different altitudes from 2200 to 3000 m from sea level. Field experiments were conducted on seven commercial fruit orchards at five ...

  2. Insect assemblage and the pollination system in cocoa ecosystems ...

    African Journals Online (AJOL)

    The rest were predominantly aerial or flying insects. The results of focal patch observation indicated that more than half of insect species resident in the cocoa ecosystem did not visit the cocoa flowers. Those which visited did not carry any pollen. Only the ceratopogonid midges (Diptera) showed higher pollinator importance.

  3. The role of honey bees as pollinators in natural areas

    Science.gov (United States)

    Clare E. Aslan; Christina T. Liang; Ben Galindo; Hill Kimberly; Walter Topete

    2016-01-01

    The western or European honey bee (Apis mellifera) is the primary managed pollinator in US agricultural systems, and its importance for food production is widely recognized. However, the role of A. mellifera as an introduced species in natural areas is potentially more complicated. The impact of A. mellifera...

  4. Flowering Dynamics and Pollinator Visitation of Oilseed Echium (Echium plantagineum)

    Science.gov (United States)

    Eberle, Carrie A.; Forcella, Frank; Gesch, Russ; Weyers, Sharon; Peterson, Dean; Eklund, James

    2014-01-01

    Echium (Echium plantagineum L.) is an alternative oilseed crop in summer-wet temperate regions that provides floral resources to pollinators. Its seed oil is rich in omega-3 fatty acids, such as stearidonic acid, which is desired highly by the cosmetic industry. Seeds were sown in field plots over three years in western Minnesota in spring (early-sown) or early summer (late-sown), and flower abundance, pollinator visitation, and seed yields were studied. Initial flowering commenced 41 to 55 d after sowing, and anthesis duration (first flowering to harvest) was 34 to 70 d. Late sowing dates delayed anthesis, but increased the intensity of visitation by pollinators. Cumulative flower densities ranged from 1 to 4.5 billion ha−1. Flowers attracted numerous honey bees (Apis mellifera L.), as many as 35 per minute of observation, which represented about 50% of all insect visitors. Early-sown echium produced seed yields up to 750 kg ha−1, which were 2–29 times higher than those of late-sown echium. Early sowing of echium in Minnesota provides abundant floral resources for pollinators for up to two months and simultaneously produces seed yields whose profits rival those of corn (Zea mays L.). PMID:25427071

  5. Pollination and yield responses of cowpea ( Vigna unguiculata L ...

    African Journals Online (AJOL)

    To determine the apicultural value of Vigna unguiculata (L.) Walp. (Fabaceae) and evaluate the Apis mellifera adansonii Latreille (Hymenoptera: Apidae) activity on its pod and seed yields, the bee foraging and pollinating activities were studied in Ngaoundéré. The experiment was carried out within the University of ...

  6. Flowering dynamics and pollinator visitation of oilseed echium (Echium plantagineum.

    Directory of Open Access Journals (Sweden)

    Carrie A Eberle

    Full Text Available Echium (Echium plantagineum L. is an alternative oilseed crop in summer-wet temperate regions that provides floral resources to pollinators. Its seed oil is rich in omega-3 fatty acids, such as stearidonic acid, which is desired highly by the cosmetic industry. Seeds were sown in field plots over three years in western Minnesota in spring (early-sown or early summer (late-sown, and flower abundance, pollinator visitation, and seed yields were studied. Initial flowering commenced 41 to 55 d after sowing, and anthesis duration (first flowering to harvest was 34 to 70 d. Late sowing dates delayed anthesis, but increased the intensity of visitation by pollinators. Cumulative flower densities ranged from 1 to 4.5 billion ha-1. Flowers attracted numerous honey bees (Apis mellifera L., as many as 35 per minute of observation, which represented about 50% of all insect visitors. Early-sown echium produced seed yields up to 750 kg ha-1, which were 2-29 times higher than those of late-sown echium. Early sowing of echium in Minnesota provides abundant floral resources for pollinators for up to two months and simultaneously produces seed yields whose profits rival those of corn (Zea mays L..

  7. Pollinator-induced twisting of flowers sidesteps floral architecture constraints

    Czech Academy of Sciences Publication Activity Database

    Bartoš, Michael; Janeček, Štěpán

    2014-01-01

    Roč. 24, č. 17 (2014), R793-R795 ISSN 0960-9822 R&D Projects: GA ČR(CZ) GAP505/11/1617 Institutional support: RVO:67985939 Keywords : bird-pollination * adaptation * reproductive barriers Subject RIV: EH - Ecology, Behaviour Impact factor: 9.571, year: 2014

  8. Breeding system and pollination biology of the semi- domesticated ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-11-19

    Nov 19, 2008 ... visits by social bees often result in a high proportion of geitonogamous pollinations .... stigmate, the proportion of pollen tubes that had reached the style and in the ovary and the proportion of fertilised ovules. ..... Functional properties of tamarind (Tamarindus indica) kernel protein. Food Chem. 49: 1-9.

  9. Beneficial Insects and Insect Pollinators on Milkweed in South Georgia

    Science.gov (United States)

    Insect pollinators are essential for the reproduction of more than two-thirds of the world’s crops, and beneficial insects play an important role in managing pest insects in agricultural farmscapes. These insects depend on nectar for their survival in these farmscapes. The flowers of tropical milkwe...

  10. Foraging and pollination behaviour of the African Honey bee ( Apis ...

    African Journals Online (AJOL)

    Foraging and pollination behaviour of the African Honey bee (Apis mellifera adansonii) on Callistemon rigidus flowers in Ngaoundere (Cameroon). F-N Tchuenguem Fohouo, J Messi, D Brüchner, B Bouba, G Mbofung, J Hentchoya Hemo. Abstract. No Abstract Available Journal of the Cameroon Academy of Sciences ...

  11. Male function for ensuring pollination and reproductive success in ...

    Indian Academy of Sciences (India)

    In Berberis lycium anthers on alternate stamens dehisce, thus prolonging the male function so that pollination is affected and reproduction is ensured. The large pollen sac of each bithecous anther after the appearance of longitudinal dehiscence slit moves away from the filament while remaining attached at the tip of the ...

  12. Metabolic control of tobacco pollination by sugars and invertases

    DEFF Research Database (Denmark)

    Goetz, Marc; Guivarc'h, Anne; Hirsche, Jörg

    2017-01-01

    Pollination in flowering plants is initiated by germination of pollen grains on stigmas followed by fast growth of pollen tubes representing highly energy-consuming processes. The symplastic isolation of pollen grains and tubes requires import of sucrose available in the apoplast. We show that th...

  13. Conserving pollinators in North American forests: A review

    Science.gov (United States)

    James L. Hanula; Michael D. Ulyshen; Scott Horn

    2016-01-01

    Bees and butterflies generally favor open forest habitats regardless of forest type, geographic region, or methods used to create these habitats. Dense shrub layers of native or nonnative species beneath forest canopies negatively impact herbaceous plant cover and diversity, and pollinators. The presence of nonnative flowers as a source of nectar, pollen, or larval...

  14. Mechanism for pollination in African yam bean | Ojuederie | African ...

    African Journals Online (AJOL)

    African yam bean (AYB) (Sphenostylis stenocarpa (Hochst Ex. A. Rich) Harms is a neglected and underutilised legume in tropical Africa. Its utilisation has been hampered by the presence of anti-nutritional factors and lack of improved varieties. The objective of this study was to investigate pollination and determine the rates ...

  15. Potential pollinators and floral visitors of introduced tropical biofuel ...

    African Journals Online (AJOL)

    Jatropha curcas L. is a tropical tree belonging to the Euphorbiaceae family with oil-rich seeds that are currently used as a source of biodisel. A better knowledge of the reproductive ecology is imperative for yield optimisation and invasiveness risk assessment. Insight in the diversity and movement of potential pollinators, ...

  16. Systematic, phylogenetic and pollination studies of Specklinia (Orchidaceae)

    NARCIS (Netherlands)

    Karremans, Adam Philip

    2015-01-01

    The present work brings together the results of systematic, phylogenetic and pollination studies of orchid species belonging to the genus Specklinia, with special emphasis on those with a Costa Rican distribution. In the first five chapter two species' complexes within Specklinia, that of S.

  17. The hymenopterous pollinators of Himalayan foot hills of Pakistan ...

    African Journals Online (AJOL)

    enoh

    2012-04-05

    Apr 5, 2012 ... (McGregor, 1976). The wild bees including bumble bees, leaf-cutting bees, alkali bees and carpenter bees are especially adopted for gathering pollens and nectars from flowers (Bohart, 1972). Pollinators other than honey bees are also extremely valuable although their value is difficult to estimate. Globally ...

  18. Cross-Pollinated Crop Variety Adoption Studies and Seed Recycling ...

    African Journals Online (AJOL)

    A survey of 126 maize farmers was conducted in northern Tanzania with the objective of examining adoption of cross-pollinated seeds among farmers who recycle improved seeds. In this study, an improved variety is defined as any variety that has been bred using formal plant breeding methods. Formally bred cultivars that ...

  19. Pollination and facultative ant-association in the African leopard ...

    African Journals Online (AJOL)

    The leopard orchid Ansellia africana (Orchidaceae) is an epiphytic species widely distributed across tropical Africa. The pollination ecology of A. africana was investigated by direct observation. Buds and stalks of A. africana exude droplets of extra-floral nectar, but mature flowers produce no nectar. The role of extra-floral ...

  20. Regeneration of Sudanese maize inbred lines and open pollinated ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-06-03

    Jun 3, 2008 ... Eight maize inbred lines and three open pollinated varieties from Sudan were evaluated for their response to tissue ... Keywords: Sudanese maize genotypes, embryogenic callus, regeneration, and tissue culture. INTRODUCTION .... genes have been implicated in the inheritance of callus induction and ...

  1. Micro-mesh fabric pollination bags for switchgrass

    Science.gov (United States)

    Pollination bags for making controlled crosses between switchgrass plants were made from a polyester micro-mesh fabric with a mesh size of 41 µm which is smaller than the mean reported 43 µm diameter of switchgrass pollen. When used in paired plant crosses between switchgrass plants, the mean amoun...

  2. Pollination biology of northern red and black oak

    Science.gov (United States)

    Robert A. Cecich; William W. Haenchen

    1995-01-01

    Pistillate flower abortion in northern red oak and black oak was evaluated in relation to pollination and fertilization. The presence, position, and characteristics of the pollen grains, pollen tubes, and ovules were determined with bright field and fluorescence microscopy. Flower survival counts were made weekly, from late April to mid- September. Both species have...

  3. Effects of Soil Quality Enhancement on Pollinator-Plant Interactions

    Directory of Open Access Journals (Sweden)

    Yasmin J. Cardoza

    2012-01-01

    Full Text Available Both biotic and abiotic factors can affect soil quality, which can significantly impact plant growth, productivity, and resistance to pests. However, the effects of soil quality on the interactions of plants with beneficial arthropods, such as pollinators, have not been extensively examined. We studied the effects of vermicompost (earthworm compost, VC soil amendment on behavioral and physiological responses of pollinators to flowers and floral resources, using cucumbers, Cucumis sativus, as our model system. Results from experiments conducted over three field seasons demonstrated that, in at least two out of three years, VC amendment significantly increased visit length, while reducing the time to first discovery. Bumblebee (Bombus impatiens workers that fed on flowers from VC-amended plants had significantly larger and more active ovaries, a measure of nutritional quality. Pollen fractions of flowers from VC-grown plants had higher protein compared to those of plants grown in chemically fertilized potting soil. Nectar sugar content also tended to be higher in flowers from VC-grown plants, but differences were not statistically significant. In conclusion, soil quality enhancement, as achieved with VC amendment in this study, can significantly affect plant-pollinator interactions and directly influences pollinator nutrition and overall performance.

  4. New England Wind Forum: A Wind Powering America Project, Newsletter #5 -- January 2010, Wind and Hydropower Technologies Program (WHTP)

    Energy Technology Data Exchange (ETDEWEB)

    Grace, R. C.; Gifford, J.

    2010-01-01

    Wind Powering America program launched the New England Wind Forum (NEWF) in 2005 to provide a single comprehensive source of up-to-date, Web-based information on a broad array of wind energy issues pertaining to New England. The NEWF newsletter provides New England stakeholders with updates on wind energy development in the region. In addition to regional updates, Issue #5 offers an interview with Angus King, former governor of Maine and co-founder of Independence Wind.

  5. Enhanced production of parthenocarpic cucumbers pollinated with stingless bees and Africanized honey bees in greenhouses

    Directory of Open Access Journals (Sweden)

    Euclides Braga Malheiros

    2013-12-01

    Full Text Available Crops have different levels of dependence on pollinators; this holds true even for cultivars of the same species, as in the case of cucumber (Cucumis sativus. The aim of this research was to assess the attractiveness of flowers of three Japanese parthenocarpic cucumber cultivars and evaluate the importance of Africanized bees (Apis mellifera, and the Brazilian native stingless bees, Jataí (Tetragonisca angustula and Iraí (Nannotrigona testaceicornis on fruit production. Several parameters, including frequency of bee visits to flowers as well as duration of nectar collection and fruit set were examined; additionally, fruit weight, length and diameter were evaluated. Three greenhouses located in Ribeirão Preto, SP, were used for planting three cucumber cultivars (Hokushin, Yoshinari and Soudai. The female flowers were more attractive than male flowers; however, Jataí bees were not observed visiting the flowers. The Africanized and the Iraí bees collected only nectar, with a visitation peak between 10 and 12h. Visits to female flowers had a longer duration than visits to male flower visits in all three cultivars. Africanized bee colonies declined due to loss of bees while in the greenhouse; the native stingless bee colonies did not suffer these losses. When bees were excluded, fruit set was 78%; however, when bees had access to the flowers, fruit set was significantly (19.2% higher. Fruit size and weight did not differ with and without bees. This demonstrates that even in parthenocarpic cucumber cultivars, which do not require pollination in order to from fruits, fruit production is significantly increased by bee pollination.

  6. How to be an attractive male: floral dimorphism and attractiveness to pollinators in a dioecious plant

    Directory of Open Access Journals (Sweden)

    Waelti Marc O

    2009-08-01

    Full Text Available Abstract Background Sexual selection theory predicts that males are limited in their reproductive success by access to mates, whereas females are more limited by resources. In animal-pollinated plants, attraction of pollinators and successful pollination is crucial for reproductive success. In dioecious plant species, males should thus be selected to increase their attractiveness to pollinators by investing more than females in floral traits that enhance pollinator visitation. We tested the prediction of higher attractiveness of male flowers in the dioecious, moth-pollinated herb Silene latifolia, by investigating floral signals (floral display and fragrance and conducting behavioral experiments with the pollinator-moth, Hadena bicruris. Results As found in previous studies, male plants produced more but smaller flowers. Male flowers, however, emitted significantly larger amounts of scent than female flowers, especially of the pollinator-attracting compounds. In behavioral tests we showed that naïve pollinator-moths preferred male over female flowers, but this preference was only significant for male moths. Conclusion Our data suggest the evolution of dimorphic floral signals is shaped by sexual selection and pollinator preferences, causing sexual conflict in both plants and pollinators.

  7. Native bees buffer the negative impact of climate warming on honey bee pollination of watermelon crops.

    Science.gov (United States)

    Rader, Romina; Reilly, James; Bartomeus, Ignasi; Winfree, Rachael

    2013-10-01

    If climate change affects pollinator-dependent crop production, this will have important implications for global food security because insect pollinators contribute to production for 75% of the leading global food crops. We investigate whether climate warming could result in indirect impacts upon crop pollination services via an overlooked mechanism, namely temperature-induced shifts in the diurnal activity patterns of pollinators. Using a large data set on bee pollination of watermelon crops, we predict how pollination services might change under various climate change scenarios. Our results show that under the most extreme IPCC scenario (A1F1), pollination services by managed honey bees are expected to decline by 14.5%, whereas pollination services provided by most native, wild taxa are predicted to increase, resulting in an estimated aggregate change in pollination services of +4.5% by 2099. We demonstrate the importance of native biodiversity in buffering the impacts of climate change, because crop pollination services would decline more steeply without the native, wild pollinators. More generally, our study provides an important example of how biodiversity can stabilize ecosystem services against environmental change. © 2013 John Wiley & Sons Ltd.

  8. Predominance of self-compatibility in hummingbird-pollinated plants in the Neotropics

    Science.gov (United States)

    Wolowski, Marina; Saad, Carolina Farias; Ashman, Tia-Lynn; Freitas, Leandro

    2013-01-01

    Both plant traits and plant-pollinator interactions are thought to influence plant mating systems. For hummingbird-pollinated plants, foraging strategy (territorial or traplining) is also expected to influence plant mating. We hypothesize that the traplining behavior of hermits promotes outcrossing, whereas the behavior of non-hermits favours self-incompatibility. Thus, selection is expected to maintain self-incompatibility in plants pollinated by non-hermits. We explore the incidence of self-incompatibility in Neotropical hummingbird-pollinated plants and its association with hummingbird behavior and plant traits. We conducted a literature review (56 species) and performed hand-pollination experiments in 27 hummingbird-pollinated plants in an Atlantic rainforest. We found that self-incompatibility (measured as hummingbird-pollinated plants. The interaction of hummingbird and habit type affected ISI, as did phylogenetic relationships. Specifically, herbs pollinated by non-hermits had higher ISI than woody plants pollinated by non-hermits, and herbs pollinated by both hermits and non-hermits. For the Atlantic rainforest plant guild, 30 % of the species were self-incompatible. ISI was higher in herbs than in woody species and increased with plant aggregation but was not dependent on foraging behavior, plant density, or floral display. Although hummingbirds differ in their foraging strategies, these behavioral differences seem to have only a minor influence on the incidence of self-incompatibility. Phylogenetic relatedness seems to be the strongest determinant of mating system in Neotropical hummingbird-pollinated plants.

  9. Wind Turbines Adaptation to the Variability of the Wind Field

    Science.gov (United States)

    Ulianov, Yuriy; Martynenko, Gennadii; Misaylov, Vitaliy; Soliannikova, Iuliia

    2010-05-01

    including combined RF-acoustic antenna installed coaxially with the gondola of the wind power turbine. The work of the technique is synchronized with rotation of blades to eliminate their shielding action. Dangerous in terms of dynamic strength is the wind load pulse, the rise time which is comparable with the period of the natural frequency of the wind turbine elements (blade, tower, rotor, etc.). The amplitude decay of resonant vibrations at critical values of the speed of rotation can be realized through the use of mechanical elastic supports with nonlinear artificial dampers. They have a high coefficient of resistance, but may cause self-excited oscillations. We propose the way to deal with raised vibration of wind turbine elements at the expense of short-term increase of damping in the range of critical rotary axis speeds or during impulsive effects of wind loadings (wind gusts). This is possible through the use of non-linear electromagnetic dampers or active magnetic bearings. Their feature is the possibility of varying the mechanical stiffness and damping properties by changing the electrical parameters of electromagnets. The controlling of these parameters is carried out by the control system (CS) with the information feedback on the spatial-temporal structure of the wind field obtained from IRASS. In the composition of the CS can also be included the rotational speed sensor of the WPT rotor. This approach to the adaptation of wind turbines will allow to reduce vibration and to perform early compensation of the load on their components, which arise under the wind gusts. In addition, corrections about the wind field obtained with IRASS, would increase the mean power of WPT.

  10. Contribution of pollinator-mediated crops to nutrients in the human food supply.

    Science.gov (United States)

    Eilers, Elisabeth J; Kremen, Claire; Smith Greenleaf, Sarah; Garber, Andrea K; Klein, Alexandra-Maria

    2011-01-01

    The contribution of nutrients from animal pollinated world crops has not previously been evaluated as a biophysical measure for the value of pollination services. This study evaluates the nutritional composition of animal-pollinated world crops. We calculated pollinator dependent and independent proportions of different nutrients of world crops, employing FAO data for crop production, USDA data for nutritional composition, and pollinator dependency data according to Klein et al. (2007). Crop plants that depend fully or partially on animal pollinators contain more than 90% of vitamin C, the whole quantity of Lycopene and almost the full quantity of the antioxidants β-cryptoxanthin and β-tocopherol, the majority of the lipid, vitamin A and related carotenoids, calcium and fluoride, and a large portion of folic acid. Ongoing pollinator decline may thus exacerbate current difficulties of providing a nutritionally adequate diet for the global human population.

  11. Contribution of pollinator-mediated crops to nutrients in the human food supply.

    Directory of Open Access Journals (Sweden)

    Elisabeth J Eilers

    Full Text Available The contribution of nutrients from animal pollinated world crops has not previously been evaluated as a biophysical measure for the value of pollination services. This study evaluates the nutritional composition of animal-pollinated world crops. We calculated pollinator dependent and independent proportions of different nutrients of world crops, employing FAO data for crop production, USDA data for nutritional composition, and pollinator dependency data according to Klein et al. (2007. Crop plants that depend fully or partially on animal pollinators contain more than 90% of vitamin C, the whole quantity of Lycopene and almost the full quantity of the antioxidants β-cryptoxanthin and β-tocopherol, the majority of the lipid, vitamin A and related carotenoids, calcium and fluoride, and a large portion of folic acid. Ongoing pollinator decline may thus exacerbate current difficulties of providing a nutritionally adequate diet for the global human population.

  12. Plant diversity increases spatio-temporal niche complementarity in plant-pollinator interactions.

    Science.gov (United States)

    Venjakob, Christine; Klein, Alexandra-Maria; Ebeling, Anne; Tscharntke, Teja; Scherber, Christoph

    2016-04-01

    Ongoing biodiversity decline impairs ecosystem processes, including pollination. Flower visitation, an important indicator of pollination services, is influenced by plant species richness. However, the spatio-temporal responses of different pollinator groups to plant species richness have not yet been analyzed experimentally. Here, we used an experimental plant species richness gradient to analyze plant-pollinator interactions with an unprecedented spatio-temporal resolution. We observed four pollinator functional groups (honeybees, bumblebees, solitary bees, and hoverflies) in experimental plots at three different vegetation strata between sunrise and sunset. Visits were modified by plant species richness interacting with time and space. Furthermore, the complementarity of pollinator functional groups in space and time was stronger in species-rich mixtures. We conclude that high plant diversity should ensure stable pollination services, mediated via spatio-temporal niche complementarity in flower visitation.

  13. Plant pollinator networks along a gradient of urbanisation.

    Directory of Open Access Journals (Sweden)

    Benoît Geslin

    Full Text Available BACKGROUND: Habitat loss is one of the principal causes of the current pollinator decline. With agricultural intensification, increasing urbanisation is among the main drivers of habitat loss. Consequently studies focusing on pollinator community structure along urbanisation gradients have increased in recent years. However, few studies have investigated how urbanisation affects plant-pollinator interaction networks. Here we assessed modifications of plant-pollinator interactions along an urbanisation gradient based on the study of their morphological relationships. METHODOLOGY/PRINCIPAL FINDINGS: Along an urbanisation gradient comprising four types of landscape contexts (semi-natural, agricultural, suburban, urban, we set up experimental plant communities containing two plant functional groups differing in their morphological traits ("open flowers" and "tubular flowers". Insect visitations on these communities were recorded to build plant-pollinator networks. A total of 17 857 interactions were recorded between experimental plant communities and flower-visitors. The number of interactions performed by flower-visitors was significantly lower in urban landscape context than in semi-natural and agricultural ones. In particular, insects such as Syrphidae and solitary bees that mostly visited the open flower functional group were significantly impacted by urbanisation, which was not the case for bumblebees. Urbanisation also impacted the generalism of flower-visitors and we detected higher interaction evenness in urban landscape context than in agricultural and suburban ones. Finally, in urban context, these modifications lowered the potential reproductive success of the open flowers functional group. CONCLUSIONS/SIGNIFICANCE: Our findings show that open flower plant species and their specific flower-visitors are especially sensitive to increasing urbanisation. These results provide new clues to improve conservation measures within urbanised areas

  14. Weak trophic links between a crab-spider and the effective pollinators of a rewardless orchid

    Science.gov (United States)

    Quintero, Carolina; Corley, Juan C.; Aizen, Marcelo A.

    2015-01-01

    Sit and wait predators hunting on flowers are considered to be exploiters of plant-pollinator mutualisms. Several studies have shown that plant-pollinator interactions can be highly susceptible to the impact of a third trophic level, via consumptive (direct) and non-consumptive (indirect) effects that alter pollinator behavior and, ultimately, plant fitness. However, most flowering plants attract a wide array of flower visitors, from which only a subset will be effective pollinators. Hence, a negative effect of an ambush predator on plant fitness should be expected only when: (i) the effective pollinators are part of the predators' diet and/or (ii) the non-consumptive effects of predator presence (e.g. dead prey) alter the behavior of effective pollinators and pollen movement among individual plants. We analyzed the direct and indirect effects of a crab-spider (Misumenops pallidus), on the pollination and reproductive success of Chloraea alpina, a Patagonian rewardless orchid. Our results indicate that most of the flower visitors do not behave as effective pollinators and most effective pollinators were not observed as prey for the crab-spider. In terms of non-consumptive effects, inflorescences with and without spiders and/or dead-prey did not vary the frequency of flower visitors, nor pollinia removal or deposition. Hence, it is not surprising that M. pallidus has a neutral effect on pollinia removal and deposition as well as on fruit and seed set. Similar to other rewardless orchids, the low reproductive success of C. alpina (∼6% fruit set) was associated with the limited number of visits by effective pollinators. Negative top-down effects of a flower-visitor predator on plant pollination may not be anticipated without studying the direct and indirect effects of this predator on the effective pollinators. In pollination systems where effective pollinators visited flowers erratically, such as in deceptive orchids, we expect weak or no effect of predators on

  15. The pollination ecology of Hedysarum boreale Nutt. (Fabaceae) and evaluation of its pollinating bees for restoration seed production

    Science.gov (United States)

    Katharine A. Swoboda

    2007-01-01

    Federal land managers desire a consistent and cost-effective source of Hedysarum boreale Nutt. seed for rangeland restoration in the Great Basin and adjacent ecosystems. The breeding biology of H. boreale was assessed via hand pollination experiments at 2 sites in Cache County, Utah, USA in 2003. H. boreale was found to be self-compatible, but did not produce fruit and...

  16. A multiple-fan active control wind tunnel for outdoor wind speed and direction simulation

    Science.gov (United States)

    Wang, Jia-Ying; Meng, Qing-Hao; Luo, Bing; Zeng, Ming

    2018-03-01

    This article presents a new type of active controlled multiple-fan wind tunnel. The wind tunnel consists of swivel plates and arrays of direct current fans, and the rotation speed of each fan and the shaft angle of each swivel plate can be controlled independently for simulating different kinds of outdoor wind fields. To measure the similarity between the simulated wind field and the outdoor wind field, wind speed and direction time series of two kinds of wind fields are recorded by nine two-dimensional ultrasonic anemometers, and then statistical properties of the wind signals in different time scales are analyzed based on the empirical mode decomposition. In addition, the complexity of wind speed and direction time series is also investigated using multiscale entropy and multivariate multiscale entropy. Results suggest that the simulated wind field in the multiple-fan wind tunnel has a high degree of similarity with the outdoor wind field.

  17. Wind energy in Europe

    International Nuclear Information System (INIS)

    Sesto, E.

    1992-02-01

    Interest in wind energy as a supplementary source for the production of electricity has recently gained renewed momentum due to widespread concern about environmental impacts from the large scale use of fossil fuels and nuclear energy. In addition, political unrest in the Middle East has drawn attention to the importance of national energy self-sufficiency. European government administrations, however, have not yet fully appreciated the real worth of the 'clean energy' afforded by wind energy. In this regard, the European Wind Energy Association (EWEA) is acting as a strong voice to inform the public and energy planners by stimulating international wind energy R ampersand D cooperation, and organizing conferences to explain the advantages of wind energy. In October 1991, EWEA published a strategy document giving a picture of the real possibilities offered by wind energy within the geographical, social, and European economic context. This paper provides an overview of the more significant features to emerge from this document which represents a useful guideline for wind power plant technical/economic feasibility studies in that it contains brief notes on resource availability, land requirements, visual and acoustic impacts, turbine sizing, performance, interconnection to utility grids, maintenance and operating costs, safety, as well as, on marketing aspects

  18. Aromas florales y su interacción con los insectos polinizadores Floral scents and their interaction with insect pollinators

    Directory of Open Access Journals (Sweden)

    Julieta Grajales-Conesa

    2011-12-01

    Full Text Available Las plantas emplean diversas señales visuales y olfativas con la finalidad de atraer a los polinizadores que en su mayoría son insectos. Algunas plantas han desarrollado mecanismos, basándose en mensajes olfativos que los hacen únicos para sus polinizadores específicos. Estos mecanismos, así como las variaciones intra- e interespecíficas en el perfil de los aromas florales han evolucionado para determinadas especies. Los aromas florales son un conjunto de compuestos volátiles orgánicos y para su estudio hay varios métodos que requieren de técnicas que cada vez son más eficientes. El uso de estos aromas podría ser una opción en determinados sistemas de polinización, utilizándolos como atrayente de polinizadores o de depredadores y/o herbívoro para incrementar la producción y disminuir los daños por plagas. En este trabajo se revisan las distintas interacciones de los insectos y los aromas florales, los sistemas específicos planta-polinizador, los métodos de análisis, así como algunos patrones o tendencias de estas interacciones y su aplicación e importancia.Plants use visual and olfactory cues to attract pollinators and to allow them to detect the presence of flowers, which most of them are insects. Some plants have evolved with their pollinators, based on the olfactory messages, which make them unique for their specific pollinators. These mechanisms have evolved in certain plants in relation to their pollinators, and there are also inter and intra-specific variation in fragrance cues which show specific chemical profile for each plant species, so insects attracted are specific to them. Most of the floral scents are organic compounds identified with techniques and methodologies which become more specific and efficient along the time. The application of floral scent could be used as a tool in pollination and pest management. In these studies, insect interaction with floral scent is reviewed and specificity of plant-pollinator

  19. Damping Wind and Wave Loads on a Floating Wind Turbine

    DEFF Research Database (Denmark)

    Christiansen, Søren; Bak, Thomas; Knudsen, Torben

    2013-01-01

    Offshore wind energy capitalizes on the higher and less turbulent wind speeds at sea. To enable deployment of wind turbines in deep-water locations, structures are being explored, where wind turbines are placed on a floating platform. This combined structure presents a new control problem, due...... to the partly unconstrained movement of the platform and ocean wave excitation. If this additional complexity is not dealt with properly, this may lead to a significant increase in the structural loads and, potentially, instability of the controlled system. In this paper, the wave excitation is investigated......, and we show the influence that both wind speed, wave frequencies and misalignment between wind and waves have on the system dynamics. A new control model is derived that extends standard turbine models to include the hydrodynamics, additional platform degrees of freedom, the platform mooring system...

  20. Perfect Syncarpy in Apple (Malus × domestica ‘Summerland McIntosh’) and its Implications for Pollination, Seed Distribution and Fruit Production (Rosaceae: Maloideae)

    Science.gov (United States)

    SHEFFIELD, CORY S.; SMITH, ROBERT F.; KEVAN, PETER G.

    2005-01-01

    • Background and Aims The gynoecium of the domestic apple, Malus × domestica, has been assumed to be imperfectly syncarpic, whereby pollination of each stigmatic surface can result in fertilization within only one of the five carpels. Despite its implied effect on fruit quantity and quality, the resulting influence of flower form on seed set and distribution within the apple fruit has seldom been investigated. Instead, poor fruit quality is usually attributed to problems with pollination, such as low bee numbers and/or ineffective pollinators within apple agro-ecosystems. The objective of this study was to determine the true nature of gynoecial structure and its influence on fruit production in the apple cultivar ‘Summerland McIntosh’. • Methods A stigma-excision method was used to determine the effects of uneven pollination among the five stigmas on fruit quantity (as measured by fruit set), and quality (seed number and distribution). In addition, flowers were examined microscopically to determine pollen tube pathways. • Key Results Fruit set, seed number, seed distribution, and the microscopic examination of flower gynoecial structure reported in this study indicated that the gynoecium of the cultivar Summerland McIntosh is perfectly syncarpic and not imperfectly syncarpic as previously thought. • Conclusions Pollination levels among the five stigmas need not be uniform to obtain full seed development within Summerland McIntosh fruit; even if one stigmatic surface is adequately pollinated, a full complement of seeds is likely. The importance of perfect syncarpy in recognizing true causes of poor fruit quality in apple is discussed. Cory S. Sheffield, Robert F. Smith and Peter G. Kevan For the Department of Agriculture and Agri-Food, Government of Canada PMID:15661749

  1. Beetle pollination and flowering rhythm of Annona coriacea Mart. (Annonaceae) in Brazilian cerrado: Behavioral features of its principal pollinators.

    Science.gov (United States)

    Costa, Marilza Silva; Silva, Ricardo José; Paulino-Neto, Hipólito Ferreira; Pereira, Mônica Josene Barbosa

    2017-01-01

    The conservation and sustainable management of Annona coriacea requires knowledge of its floral and reproductive biology, and of its main pollinators and their life cycles. In this work, we analyzed these aspects in detail. Floral biology was assessed by observing flowers from the beginning of anthesis to senescence. The visiting hours and behavior of floral visitors in the floral chamber were recorded, as were the sites of oviposition. Excavations were undertaken around specimens of A. coriacea to determine the location of immature pollinators. Anthesis was nocturnal, starting at sunset, and lasted for 52-56 h. The flowers were bisexual, protogynous and emitted a strong scent similar to the plant´s own ripe fruit. There was pronounced synchrony among all floral events (the period and duration of stigmatic receptivity, release of odor, pollen release and drooping flowers) in different individuals, but no synchrony in the same individuals. All of the flowers monitored were visited by beetle species of the genera Cyclocephala and Arriguttia. Beetles arrived at the flowers with their bodies covered in pollen and these pollen grains were transferred to the stigmata while foraging on nutritious tissues at the base of the petals. With dehiscence of the stamens and retention within the floral chamber, the bodies of the floral visitors were again covered with pollen which they carried to newly opened flowers, thus promoting the cycle of pollination. After leaving the flowers, female beetles often excavated holes in the soil to lay eggs. Larvae were found between the leaf litter and the first layer of soil under specimens of A. coriacea. Cyclocephala beetles were the main pollinators of A. coriacea, but Arriguttia brevissima was also considered a pollinator and is the first species of this genus to be observed in Annonaceae flowers. Annona coriacea was found to be self-compatible with a low reproductive efficiency in the area studied. The results of this investigation

  2. Wind farm production estimates

    DEFF Research Database (Denmark)

    Larsen, Torben J.; Larsen, Gunner Chr.; Aagaard Madsen, Helge

    2012-01-01

    inves- tigated for a full polar (i.e. as function of mean inflow wind direction). This investigation relates to a mean wind speed bin defined as 8m=s±1m=s. The impact of ambient turbu- lence intensity and turbine inter spacing on the production of a wind turbine operating under full wake conditions...... is investi- gated. Four different turbine inter spacings, ranging between 3.8 and 10.4 rotor diameters, are analyzed for ambient turbu- lence intensities varying between 2% and 20%. This analysis is based on full scale production data from three other wind farms Wieringermeer [3], Horns Rev [4] and Nysted [5......]. A very satisfactory agreement between experimental data and predictions is observed. This paper finally includes additionally an analysis of the production impact caused by atmospheric stability effects. For this study, atmospheric stability conditions are defined in terms of the Monin-Obukhov length...

  3. South Baltic Wind Atlas

    DEFF Research Database (Denmark)

    Pena Diaz, Alfredo; Hahmann, Andrea N.; Hasager, Charlotte Bay

    A first version of a wind atlas for the South Baltic Sea has been developed using the WRF mesoscale model and verified by data from tall Danish and German masts. Six different boundary-layer parametrization schemes were evaluated by comparing the WRF results to the observed wind profiles...... at the masts. The WRF modeling was done in a nested domain of high spatial resolution for 4 years. In addition the longterm wind statistics using the NCAR-NCEP reanalysis data were performed during 30 years to provide basis for a long-term adjustment of the results and the final WRF results include a weighting...... for the long-term trends variability in the South Baltic Sea. Observations from Earth observing satellites were used to evaluate the spatial resolution of the WRF model results near the surface. The QuikSCAT and the WRF results compared well whereas the Envisat ASAR mean wind map showed some variation...

  4. Wind Turbine Providing Grid Support

    DEFF Research Database (Denmark)

    2011-01-01

    A variable speed wind turbine is arranged to provide additional electrical power to counteract non-periodic disturbances in an electrical grid. A controller monitors events indicating a need to increase the electrical output power from the wind turbine to the electrical grid. The controller...... is arranged to control the wind turbine as follows: after an indicating event has been detected, the wind turbine enters an overproduction period in which the electrical output power is increased, wherein the additional electrical output power is taken from kinetic energy stored in the rotor and without...... changing the operation of the wind turbine to a more efficient working point.; When the rotational speed of the rotor reaches a minimum value, the wind turbine enters a recovery period to re-accelerate the rotor to the nominal rotational speed while further contributing to the stability of the electrical...

  5. Wind height distribution influence on offshore wind farm feasibility study

    Science.gov (United States)

    Benassai, Guido; Della Morte, Renata; Matarazzo, Antonio; Cozzolino, Luca

    2015-04-01

    The economic feasibility of offshore wind power utilization depends on the favourable wind conditions offshore as compared to sites on land. The higher wind speeds have to compensate the additional cost of offshore developments. However, not only the mean wind speed is different, but the whole flow regime, as can be seen in the vertical wind speed profile. The commonly used models to describe this profile have been developed mainly for land sites, so they have to be verified on the basis of field data. Monin-Obukhov theory is often used for the description of the wind speed profile at a different height with respect to a measurement height. Starting from the former, , the profile is predicted using two parameters, Obukhov length and sea surface roughness. For situations with near-neutral and stable atmospheric stratification and long (>30km) fetch, the wind speed increase with height is larger than what is predicted from Monin-Obukhov theory. It is also found that this deviation occurs at wind speeds important for wind power utilization, mainly at 5-9 ms-1. In the present study the influence of these aspects on the potential site productivity of an offshore wind farm were investigated, namely the deviation from the theory of Monin-Obukhov due to atmospheric stability and the influence of the fetch length on the Charnock model. Both these physical effects were discussed and examined in view of a feasibility study of a site for offshore wind farm in Southern Italy. Available data consisted of time histories of wind speeds and directions collected by National Tidegauge Network (Rete Mareografica Nazionale) at the height of 10m a.s.l. in ports. The theory of Monin-Obukhov was used to extrapolate the data to the height of the wind blades, while the Charnock model was used to extend the wind speed on the sea surface from the friction velocity on the ground. The models described were used to perform calculations for a feasibility study of an offshore wind farm in Southern

  6. Population dependence in the interactions with neighbors for pollination: A field experiment with Taraxacum officinale.

    Science.gov (United States)

    Lázaro, Amparo; Totland, Orjan

    2010-05-01

    PREMISE OF THE STUDY. The fitness of plants depends on their immediate biotic and abiotic environmental surroundings. The floral neighborhood of individual plants is part of this immediate environment and affects the frequency and behavior of their pollinators. However, the interactions among plants for pollination might differ among populations because populations differ in floral densities and pollinator assemblages. Despite that, manipulative experiments of the floral neighborhood in different populations with a specific focus on pollinator behavior are still rare. METHODS. We introduced mixtures of two species (Salvia farinacae and Tagetes bonanza) in two populations of Taraxacum officinale and examined their effect on pollinators' foraging behavior on Taraxacum. KEY RESULTS. The effects of the heterospecific neighborhood differed among pollinator groups and between the two populations. Only honeybees consistently preferred both the most diverse (containing three species) and completely pure patches of Taraxacum in both populations. We found a strong and positive effect of patch diversity on visitation to Taraxacum in one population, whereas in the other population either no effect or a negative effect of plant diversity occurred, which we attribute to differences between populations in the ratio of pollinators to inflorescences. Pollinator visitation consistently increased with local Taraxacum density in both populations. CONCLUSIONS. Our study shows that a similar local neighborhood can differentially affect the frequency and foraging behavior of pollinators, even in closely situated populations. Experimental studies conducted in several populations would contribute to determine which factors drive the variation in pollination interactions among populations.

  7. Determination of suitable pollinizers for some selected local persimmon (Diospyros kaki L. types

    Directory of Open Access Journals (Sweden)

    Fatma Seren SAĞIR

    2012-12-01

    Full Text Available Selection of suitable pollinizers is very important for persimmon that have a widespread problem in fruit setting. This study aims to contribute for solving this problem. Study was carried out in 2010 vegetation period with 17 years old persimmon trees in Adana conditions. For this purpose, the suitability of Bruniquel and Ghora Gali pollinizer cultivars were searched for 9 local persimmon types (07TH05, 07TH06, 07TH13, 07TH14, 07TH17, 31TH01, 31TH02, 31TH03 and 33TH01. In laboratory tests of pollen viability, germination and quantity, it was determined that the potential of Ghora Gali and Bruniquel is satisfactory for a pollinizer. With controlled-pollination treatments, fruit drop was reduced compared with open pollination and non-pollination treatments. In terms of this, the best pollinator for 07TH14 and 33TH01 was Bruniquel and for 07TH06 and 07TH17 it was Ghora Gali. Both Bruniquel and Ghora Gali became suitable pollinators for 07TH05. In 07TH13, 31TH02 and 31TH03 genotypes, the best results were obtained from open pollination treatments. At the same time, 07TH14 and 33TH01 genotypes have high affinity to parthenocarpy because of their fruit set ability while there is not any pollinizer.

  8. Low functional diversity promotes niche changes in natural island pollinator communities

    Science.gov (United States)

    2017-01-01

    Functional diversity loss among pollinators has rapidly progressed across the globe and is expected to influence plant–pollinator interactions in natural communities. Although recent findings suggest that the disappearance of a certain pollinator functional group may cause niche expansions and/or shifts in other groups, no study has examined this prediction in natural communities with high plant and pollinator diversities. By comparing coastal pollination networks on continental and oceanic islands, we examined how community-level flower visit patterns are influenced by the relative biomass of long-tongued pollinators (RBLP). We found that RBLP significantly correlated with pollinator functional diversity and was lower in oceanic than in continental islands. Pollinator niches shifted with decreasing RBLP, such that diverse species with various proboscis lengths, especially short-tongued species, increasingly visited long-tubed flowers. However, we found no conspicuous negative impacts of low RBLP and the consequent niche shifts on pollinator visit frequencies to flowers in oceanic island communities. Notably, fruit set significantly decreased as RBLP decreased in a study plant species. These results suggest that niche shifts by other functional groups can generally compensate for a decline in long-tongued pollinators in natural communities, but there may be negative impacts on plant reproduction. PMID:28077773

  9. Relationship between pollination and cell wall properties in common fig fruit.

    Science.gov (United States)

    Trad, Mehdi; Ginies, Christian; Gaaliche, Badii; Renard, Catherine M G C; Mars, Messaoud

    2014-02-01

    Most botanical types in fig Ficus carica require pollination to fulfil their development and ensure quality onset of the fruit. Cell wall behaviour and composition was followed in fig fruit in response to pollination during maturity. Figs, when ripe, soften drastically and lose of their firmness and cell wall cohesion. Pollination increased peel thickness, flesh thickness, fresh weight and dry matter content of the fruit. Alcohol insoluble solids (AIS), more concentrated in the flesh tissue, were not influenced by the lack of pollination. Concentrations in uronic acids were higher in the AIS of the peel than that of the flesh and differences were significant between pollinated and non-pollinated fruits. Pectin polymers in figs were high methylated (DM>50). The methylation degree (DM) increased more with pollination affecting textural properties of the fig receptacle. The major neutral sugars from the AIS were glucose (Glc) from cellulose followed by arabinose (Ara). No significant changes in neutral sugars content could be allocated to pollination. Pollination is essential in fruit enlargement and softening. Minor changes were determined in the cell wall composition of the fruit at maturity. Fertile seeds resulting from pollination may possibly take place in hormonal activity stimulating many related enzymes of the wall matrix depolymerisation in particular polygalacturonase (PG) and pectin methylesterase (PME). Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. Tropical Forest Fragmentation Limits Movements, but Not Occurrence of a Generalist Pollinator Species.

    Directory of Open Access Journals (Sweden)

    Noelia L Volpe

    Full Text Available Habitat loss and fragmentation influence species distributions and therefore ecological processes that depend upon them. Pollination may be particularly susceptible to fragmentation, as it depends on frequent pollinator movement. Unfortunately, most pollinators are too small to track efficiently which has precluded testing the hypothesis that habitat fragmentation reduces or eliminates pollen flow by disrupting pollinator movement. We used radio-telemetry to examine space use of the green hermit hummingbird (Phaethornis guy, an important 'hub' pollinator of understory flowering plants across substantial portions of the neotropics and the primary pollinator of a keystone plant which shows reduced pollination success in fragmented landscapes. We found that green hermits strongly avoided crossing large stretches of non-forested matrix and preferred to move along stream corridors. Forest gaps as small as 50 m diminished the odds of movement by 50%. Green hermits occurred almost exclusively inside the forest, with the odds of occurrence being 8 times higher at points with >95% canopy cover compared with points having <5% canopy cover. Nevertheless, surprisingly. the species occurred in fragmented landscapes with low amounts of forest (~30% within a 2 km radius. Our results indicate that although green hermits are present even in landscapes with low amounts of tropical forest, movement within these landscapes ends up strongly constrained by forest gaps. Restricted movement of pollinators may be an underappreciated mechanism for widespread declines in pollination and plant fitness in fragmented landscapes, even when in the presence of appropriate pollinators.

  11. Selection by pollinators on floral traits in generalized Trollius ranunculoides (Ranunculaceae along altitudinal gradients.

    Directory of Open Access Journals (Sweden)

    Zhi-Gang Zhao

    Full Text Available Abundance and visitation of pollinator assemblages tend to decrease with altitude, leading to an increase in pollen limitation. Thus increased competition for pollinators may generate stronger selection on attractive traits of flowers at high elevations and cause floral adaptive evolution. Few studies have related geographically variable selection from pollinators and intraspecific floral differentiation. We investigated the variation of Trollius ranunculoides flowers and its pollinators along an altitudinal gradient on the eastern Qinghai-Tibet Plateau, and measured phenotypic selection by pollinators on floral traits across populations. The results showed significant decline of visitation rate of bees along altitudinal gradients, while flies was unchanged. When fitness is estimated by the visitation rate rather than the seed number per plant, phenotypic selection on the sepal length and width shows a significant correlation between the selection strength and the altitude, with stronger selection at higher altitudes. However, significant decreases in the sepal length and width of T. ranunculoides along the altitudinal gradient did not correspond to stronger selection of pollinators. In contrast to the pollinator visitation, mean annual precipitation negatively affected the sepal length and width, and contributed more to geographical variation in measured floral traits than the visitation rate of pollinators. Therefore, the sepal size may have been influenced by conflicting selection pressures from biotic and abiotic selective agents. This study supports the hypothesis that lower pollinator availability at high altitude can intensify selection on flower attractive traits, but abiotic selection is preventing a response to selection from pollinators.

  12. Greater pollination generalization is not associated with reduced constraints on corolla shape in Antillean plants.

    Science.gov (United States)

    Joly, Simon; Lambert, François; Alexandre, Hermine; Clavel, Julien; Léveillé-Bourret, Étienne; Clark, John L

    2018-02-01

    Flowers show important structural variation as reproductive organs but the evolutionary forces underlying this diversity are still poorly understood. In animal-pollinated species, flower shape is strongly fashioned by selection imposed by pollinators, which is expected to vary according to guilds of effective pollinators. Using the Antillean subtribe Gesneriinae (Gesneriaceae), we tested the hypothesis that pollination specialists pollinated by one functional type of pollinator have maintained more similar corolla shapes through time due to more constant and stronger selection constraints compared to species with more generalist pollination strategies. Using geometric morphometrics and evolutionary models, we showed that the corolla of hummingbird specialists, bat specialists, and species with a mixed-pollination strategy (pollinated by hummingbirds and bats; thus a more generalist strategy) have distinct shapes and that these shapes have evolved under evolutionary constraints. However, we did not find support for greater disparity in corolla shape of more generalist species. This could be because the corolla shape of more generalist species in subtribe Gesneriinae, which has evolved multiple times, is finely adapted to be effectively pollinated by both bats and hummingbirds. These results suggest that ecological generalization is not necessarily associated with relaxed selection constraints. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.

  13. Low functional diversity promotes niche changes in natural island pollinator communities.

    Science.gov (United States)

    Hiraiwa, Masayoshi K; Ushimaru, Atushi

    2017-01-11

    Functional diversity loss among pollinators has rapidly progressed across the globe and is expected to influence plant-pollinator interactions in natural communities. Although recent findings suggest that the disappearance of a certain pollinator functional group may cause niche expansions and/or shifts in other groups, no study has examined this prediction in natural communities with high plant and pollinator diversities. By comparing coastal pollination networks on continental and oceanic islands, we examined how community-level flower visit patterns are influenced by the relative biomass of long-tongued pollinators (RBLP). We found that RBLP significantly correlated with pollinator functional diversity and was lower in oceanic than in continental islands. Pollinator niches shifted with decreasing RBLP, such that diverse species with various proboscis lengths, especially short-tongued species, increasingly visited long-tubed flowers. However, we found no conspicuous negative impacts of low RBLP and the consequent niche shifts on pollinator visit frequencies to flowers in oceanic island communities. Notably, fruit set significantly decreased as RBLP decreased in a study plant species. These results suggest that niche shifts by other functional groups can generally compensate for a decline in long-tongued pollinators in natural communities, but there may be negative impacts on plant reproduction. © 2017 The Author(s).

  14. Spatial heterogeneity and the distribution of bromeliad pollinators in the Atlantic Forest

    Science.gov (United States)

    Varassin, Isabela Galarda; Sazima, Marlies

    2012-08-01

    Interactions between plants and their pollinators are influenced by environmental heterogeneity, resulting in small-scale variations in interactions. This may influence pollinator co-existence and plant reproductive success. This study, conducted at the Estação Biológica de Santa Lúcia (EBSL), a remnant of the Atlantic Forest in southeastern Brazil, investigated the effect of small-scale spatial variations on the interactions between bromeliads and their pollinators. Overall, hummingbirds pollinated 19 of 23 bromeliad species, of which 11 were also pollinated by bees and/or butterflies. However, spatial heterogeneity unrelated to the spatial location of plots or bromeliad species abundance influenced the presence of pollinators. Hummingbirds were the most ubiquitous pollinators at the high-elevation transect, with insect participation clearly declining as transect elevation increased. In the redundancy analysis, the presence of the hummingbird species Phaethornis eurynome, Phaethornis squalidus, Ramphodon naevius, and Thalurania glaucopis, and the butterfly species Heliconius erato and Heliconius nattereri in each plot was correlated with environmental factors such as bromeliad and tree abundance, and was also correlated with horizontal diversity. Since plant-pollinator interactions varied within the environmental mosaics at the study site, this small-scale environmental heterogeneity may relax competition among pollinators, and may explain the high diversity of bromeliads and pollinators generally found in the Atlantic Forest.

  15. 2016 Wind Technologies Market Report

    Energy Technology Data Exchange (ETDEWEB)

    Wiser, Ryan [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Bolinger, Mark [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2017-08-08

    Wind power capacity in the United States experienced strong growth in 2016. Recent and projected near-term growth is supported by the industry’s primary federal incentive—the production tax credit (PTC)—as well as a myriad of state-level policies. Wind additions have also been driven by improvements in the cost and performance of wind power technologies, yielding low power sales prices for utility, corporate, and other purchasers.

  16. Looks matter: changes in flower form affect pollination effectiveness in a sexually deceptive orchid.

    Science.gov (United States)

    Rakosy, D; Cuervo, M; Paulus, H F; Ayasse, M

    2017-11-01

    Many species of the sexually deceptive genus Ophrys are characterized by insect-like flowers. Their form has been traditionally considered to play an important role in pollinator attraction and manipulation. Yet, the evolution of the floral form remains insufficiently understood. We hypothesize that pollinator-mediated selection is essential for driving floral form evolution in Ophrys, but that form components are being subjected to varying selection pressures depending on their role in mediating interactions with pollinators. By using the Eucera-pollinated Ophrys leochroma as a model, our aim has been to assess whether and in what manner pollination effectiveness is altered by experimental manipulation of the flower form. Our results show that floral form plays an essential and, so far, underestimated role in ensuring effective pollination by mechanically guiding pollinators towards the reproductive structures of the flower. Pollinators are significantly less effective in interacting with flowers having forms altered to resemble those of species pollinated by different hymenopteran genera. Further, those components used by pollinators as gripping points were found to be more effective in ensuring pollinia transfer than those with which pollinators do not directly interact. Thus, mechanically active and inactive components appear to be under different selection pressures. As a consequence, mechanically active components of the flower form could reflect adaptations to the interaction with particular pollinator groups, whereas mechanically inactive components can vary more freely. Disentangling selection patterns between the functionally different components of flower form may provide valuable insights into the mechanisms driving the morphological diversification of sexually deceptive pollination systems. © 2017 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2017 European Society For Evolutionary Biology.

  17. Twenty-five years of progress in understanding pollination mechanisms in palms (Arecaceae)

    Science.gov (United States)

    Barfod, Anders S.; Hagen, Melanie; Borchsenius, Finn

    2011-01-01

    Background With more than 90 published studies of pollination mechanisms, the palm family is one of the better studied tropical families of angiosperms. Understanding palm–pollinator interactions has implications for tropical silviculture, agroforestry and horticulture, as well as for our understanding of palm evolution and diversification. We review the rich literature on pollination mechanisms in palms that has appeared since the last review of palm pollination studies was published 25 years ago. Scope and Conclusions Visitors to palm inflorescences are attracted by rewards such as food, shelter and oviposition sites. The interaction between the palm and its visiting fauna represents a trade-off between the services provided by the potential pollinators and the antagonistic activities of other insect visitors. Evidence suggests that beetles constitute the most important group of pollinators in palms, followed by bees and flies. Occasional pollinators include mammals (e.g. bats and marsupials) and even crabs. Comparative studies of palm–pollinator interactions in closely related palm species document transitions in floral morphology, phenology and anatomy correlated with shifts in pollination vectors. Synecological studies show that asynchronous flowering and partitioning of pollinator guilds may be important regulators of gene flow between closely related sympatric taxa and potential drivers of speciation processes. Studies of larger plant–pollinator networks point out the importance of competition for pollinators between palms and other flowering plants and document how the insect communities in tropical forest canopies probably influence the reproductive success of palms. However, published studies have a strong geographical bias towards the South American region and a taxonomic bias towards the tribe Cocoseae. Future studies should try to correct this imbalance to provide a more representative picture of pollination mechanisms and their evolutionary

  18. On the success of a swindle: pollination by deception in orchids

    Science.gov (United States)

    Schiestl, Florian P.

    2005-06-01

    A standing enigma in pollination ecology is the evolution of pollinator attraction without offering reward in about one third of all orchid species. Here I review concepts of pollination by deception, and in particular recent findings in the pollination syndromes of food deception and sexual deception in orchids. Deceptive orchids mimic floral signals of rewarding plants (food deception) or mating signals of receptive females (sexual deception) to attract pollen vectors. In some food deceptive orchids, similarities in the spectral reflectance visible to the pollinator in a model plant and its mimic, and increased reproductive success of the mimic in the presence of the model have been demonstrated. Other species do not mimic specific model plants but attract pollinators with general attractive floral signals. In sexually deceptive orchids, floral odor is the key trait for pollinator attraction, and behaviorally active compounds in the orchids are identical to the sex pheromone of the pollinator species. Deceptive orchids often show high variability in floral signals, which may be maintained by negative frequency-dependent selection, since pollinators can learn and subsequently avoid common deceptive morphs more quickly than rare ones. The evolution of obligate deception in orchids seems paradoxical in the light of the typically lower fruit set than in rewarding species. Pollination by deception, however, can reduce self-pollination and encourage pollen flow over longer distances, thus promoting outbreeding. Although some food deceptive orchids are isolated through postzygotic reproductive barriers, sexually deceptive orchids lack post-mating barriers and species isolation is achieved via specific pollinator attraction. Recent population genetic and phylogenetic investigations suggest gene-flow within subgeneric clades, but pollinator-mediated selection may maintain species-specific floral traits.

  19. Floral features, pollination biology and breeding system of Chloraea membranacea Lindl. (Orchidaceae: Chloraeinae)

    Science.gov (United States)

    Sanguinetti, Agustin; Buzatto, Cristiano Roberto; Pedron, Marcelo; Davies, Kevin L.; Ferreira, Pedro Maria de Abreu; Maldonado, Sara; Singer, Rodrigo B.

    2012-01-01

    Background and Aims The pollination biology of very few Chloraeinae orchids has been studied to date, and most of these studies have focused on breeding systems and fruiting success. Chloraea membranacea Lindl. is one of the few non-Andean species in this group, and the aim of the present contribution is to elucidate the pollination biology, functional floral morphology and breeding system in native populations of this species from Argentina (Buenos Aires) and Brazil (Rio Grande do Sul State). Methods Floral features were examined using light microscopy, and scanning and transmission electron microscopy. The breeding system was studied by means of controlled pollinations applied to plants, either bagged in the field or cultivated in a glasshouse. Pollination observations were made on natural populations, and pollinator behaviour was recorded by means of photography and video. Key Results Both Argentinean and Brazilian plants were very consistent regarding all studied features. Flowers are nectarless but scented and anatomical analysis indicates that the dark, clavate projections on the adaxial labellar surface are osmophores (scent-producing glands). The plants are self-compatible but pollinator-dependent. The fruit-set obtained through cross-pollination and manual self-pollination was almost identical. The main pollinators are male and female Halictidae bees that withdraw the pollinarium when leaving the flower. Remarkably, the bees tend to visit more than one flower per inflorescence, thus promoting self-pollination (geitonogamy). Fruiting success in Brazilian plants reached 60·78 % in 2010 and 46 % in 2011. Some pollinarium-laden female bees were observed transferring pollen from the carried pollinarium to their hind legs. The use of pollen by pollinators is a rare record for Orchidaceae in general. Conclusions Chloraea membrancea is pollinated by deceit. Together, self-compatibility, pollinarium texture, pollinator abundance and behaviour may account for the

  20. Lack of pollinators limits fruit production in commercial blueberry (Vaccinium corymbosum).

    Science.gov (United States)

    Benjamin, Faye E; Winfree, Rachael

    2014-12-01

    Modern agriculture relies on domesticated pollinators such as the honey bee (Apis mellifera L.), and to a lesser extent on native pollinators, for the production of animal-pollinated crops. There is growing concern that pollinator availability may not keep pace with increasing agricultural production. However, whether crop production is in fact pollen-limited at the field scale has rarely been studied. Here, we ask whether commercial highbush blueberry (Vaccinium corymbosum L.) production in New Jersey is limited by a lack of pollination even when growers provide honey bees at recommended densities. We studied two varieties of blueberry over 3 yr to determine whether blueberry crop production is pollen-limited and to measure the relative contributions of honey bees and native bees to blueberry pollination. We found two lines of evidence for pollen limitation. First, berries receiving supplemental hand-pollination were generally heavier than berries receiving ambient pollination. Second, mean berry mass increased significantly and nonasymptotically with honey bee flower visitation rate. While honey bees provided 86% of pollination and thus drove the findings reported above, native bees still contributed 14% of total pollination even in our conventionally managed, high-input agricultural system. Honey bees and native bees were also similarly efficient as pollinators on a per-visit basis. Overall, our study shows that pollination can be a limiting factor in commercial fruit production. Yields might increase with increased honey bee stocking rates and improved dispersal of hives within crop fields, and with habitat restoration to increase pollination provided by native bees.

  1. Landscape configurational heterogeneity by small-scale agriculture, not crop diversity, maintains pollinators and plant reproduction in western Europe.

    Science.gov (United States)

    Hass, Annika L; Kormann, Urs G; Tscharntke, Teja; Clough, Yann; Baillod, Aliette Bosem; Sirami, Clélia; Fahrig, Lenore; Martin, Jean-Louis; Baudry, Jacques; Bertrand, Colette; Bosch, Jordi; Brotons, Lluís; Burel, Françoise; Georges, Romain; Giralt, David; Marcos-García, María Á; Ricarte, Antonio; Siriwardena, Gavin; Batáry, Péter

    2018-02-14

    Agricultural intensification is one of the main causes for the current biodiversity crisis. While reversing habitat loss on agricultural land is challenging, increasing the farmland configurational heterogeneity (higher field border density) and farmland compositional heterogeneity (higher crop diversity) has been proposed to counteract some habitat loss. Here, we tested whether increased farmland configurational and compositional heterogeneity promote wild pollinators and plant reproduction in 229 landscapes located in four major western European agricultural regions. High-field border density consistently increased wild bee abundance and seed set of radish ( Raphanus sativus ), probably through enhanced connectivity. In particular, we demonstrate the importance of crop-crop borders for pollinator movement as an additional experiment showed higher transfer of a pollen analogue along crop-crop borders than across fields or along semi-natural crop borders. By contrast, high crop diversity reduced bee abundance, probably due to an increase of crop types with particularly intensive management. This highlights the importance of crop identity when higher crop diversity is promoted. Our results show that small-scale agricultural systems can boost pollinators and plant reproduction. Agri-environmental policies should therefore aim to halt and reverse the current trend of increasing field sizes and to reduce the amount of crop types with particularly intensive management. © 2018 The Author(s).

  2. Presence, distribution and effect of white, pink and purple morphs on pollination in the orchid Orchis mascula

    Directory of Open Access Journals (Sweden)

    Bertrand Schatz

    2013-12-01

    Full Text Available How floral polymorphism of flowering plants can be maintained in evolutionary time has long intrigued ecologists and is still debated. In particular, how floral colour polymorphism influences reproductive success is still poorly understood. Here, we investigated the case of Orchis mascula, a deceptive orchid species in which the presence of rare white-flowered individuals is known to increase the percentage pollination of co-occurring coloured morphs. In a brief review, we report all the orchid species for which rare colour morphs are recorded and show that colour polymorphism occurs in most orchid genera occurring in France. In this study, more than 20,000 individuals of O. mascula were surveyed and some rare clear pink morphs were recorded. The frequencies of white-flowered and clear pink-flowered individuals were 0.59% and 0.28%, respectively. These two rare-colour flowered individuals were not randomly distributed and restricted to a few populations. In addition, the presence of pink-flowered individuals and the use of experimental pink lures resulted in an increase in the percentage pollination of surrounding purple-flowered individuals, as previously shown for white-flowered individuals and white lures. These new observations favour kin selection as the means by which floral colour polymorphism is maintained in this species. We suggest conducting comparative studies of other species in order to evaluate the importance of this mechanism in orchid pollination and that of other plant families.

  3. The chemical composition of the floral extract of Epipogium aphyllum sw. (Orchidaceae: A clue for their pollination biology

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    Jakubska-Busse Anna

    2014-01-01

    Full Text Available Epipogium aphyllum is a rare European obligate mycoheterotrophic orchid lacking chlorophyll. It has not been studied previously with respect to pollination biology. We studied the association between the composition of floral scent emission and its pollination systems. Field observation indicates that the main pollinators of Epipogium aphyllum are representatives of the genus Bombus (Hymenoptera, B. lucorum, B. hortorum, B. terrestris, B. pascuorum and B. proteus, and the genus Apis (Hymenoptera namely A. mellifera. The main potential vector (observed to accidentally carry pollen, is most likely Episyrphus balteatus (Diptera, Syrphidae. The chemical composition of the floral extracts of 4 populations of Epipogium aphyllum Sw. growing naturally in Poland and the Czech Republic was examined by gas chromatography coupled with mass spectrometry (GC-MS and high-performance liquid chromatography coupled with diode-array detection and electrospray ionization mass spectrometry (LC-ESI-MS techniques. According to GC-MS analysis, 9-tricosene, nonadecane, 1-nonadecene and nonacosane predominated in the floral extracts. The studied samples were also characterized by relatively high amounts of benzenoids, e.g. methyl cinnamate, which is known as an attractant to the males of various orchid bees. LC-ESI-MS revealed the presence of flavor compounds such as vanillin (4-hydroxy-3-methoxybenzaldehyde and its derivative acetovanillone, together with higher amounts of aliphatic and phenolic acids. Additionally, we detected the presence of indole and morphine derivatives.

  4. Fluid dynamics of two-dimensional pollination in Ruppia maritima

    Science.gov (United States)

    Musunuri, Naga; Bunker, Daniel; Pell, Susan; Pell, Fischer; Singh, Pushpendra

    2016-11-01

    The aim of this work is to understand the physics underlying the mechanisms of two-dimensional aquatic pollen dispersal, known as hydrophily. We observed two mechanisms by which the pollen released from male inflorescences of Ruppia maritima is adsorbed on a water surface: (i) inflorescences rise above the surface and after they mature their pollen mass falls onto the surface as clumps and disperses on the surface; (ii) inflorescences remain below the surface and produce air bubbles which carry their pollen mass to the surface where it disperses. In both cases dispersed pollen masses combined under the action of capillary forces to form pollen rafts. This increases the probability of pollination since the capillary force on a pollen raft towards a stigma is much larger than on a single pollen grain. The presence of a trace amount of surfactant can disrupt the pollination process so that the pollen is not transported or captured on the water surface. National Science Foundation.

  5. Avoiding a bad apple: Insect pollination enhances fruit quality and economic value☆

    Science.gov (United States)

    Garratt, M.P.D.; Breeze, T.D.; Jenner, N.; Polce, C.; Biesmeijer, J.C.; Potts, S.G.

    2014-01-01

    Insect pollination is important for food production globally and apples are one of the major fruit crops which are reliant on this ecosystem service. It is fundamentally important that the full range of benefits of insect pollination to crop production are understood, if the costs of interventions aiming to enhance pollination are to be compared against the costs of the interventions themselves. Most previous studies have simply assessed the benefits of pollination to crop yield and ignored quality benefits and how these translate through to economic values. In the present study we examine the influence of insect pollination services on farmgate output of two important UK apple varieties; Gala and Cox. Using field experiments, we quantify the influence of insect pollination on yield and importantly quality and whether either may be limited by sub-optimal insect pollination. Using an expanded bioeconomic model we value insect pollination to UK apple production and establish the potential for improvement through pollination service management. We show that insects are essential in the production of both varieties of apple in the UK and contribute a total of £36.7 million per annum, over £6 million more than the value calculated using more conventional dependence ratio methods. Insect pollination not only affects the quantity of production but can also have marked impacts on the quality of apples, influencing size, shape and effecting their classification for market. These effects are variety specific however. Due to the influence of pollination on both yield and quality in Gala, there is potential for insect pollination services to improve UK output by up to £5.7 million per annum. Our research shows that continued pollinator decline could have serious financial implications for the apple industry but there is considerable scope through management of wild pollinators or using managed pollinator augmentation, to improve the quality of production. Furthermore, we

  6. Pollination of Vietnamese Aspidistra xuansonensis (Asparagaceae) by female Cecidomyiidi flies: larvae of pollinator feed on fertile pollen in anthers of anthetic bisexual flowers.

    Science.gov (United States)

    Vislobokov, Nikolay A; Galinskaya, Tatiana V; Degtjareva, Galina V; Valiejo-Roman, Carmen M; Samigullin, Tahir H; Kuznetsov, Andrey N; Sokoloff, Dmitry D

    2014-09-01

    • Aspidistra is a species-rich, herbaceous monocot genus of tropical Southeast Asia. Most species are recently discovered and apparently endangered, though virtually nothing is known about their biology. Species of the genus are primarily distinguished using flower morphology, which is enormously diverse. However, the pollination process has not been directly observed in the center of diversity of the genus (N Vietnam and S China). Indirect and partly direct data on the only widely cultivated species of the genus (A. elatior) placed it among angiosperms with the most unusual pollination biology, though these data are highly controversial, suggesting pollen transfer by mollusks, crustaceans, flies, or possibly tiny soil invertebrates such as collembolans.• Pollination of Aspidistra xuansonensis in the center of diversity of the genus was studied using visual observations and videos and light and scanning electron microscopy investigation of flowers and their pollinators. Pollinators and their larvae were molecularly barcoded.• Aspidistra xuansonensis is pollinated by female cecidomyiid flies (gall midges). They oviposit on anthers, and larvae develop among the pollen mass. Molecular barcoding proved taxonomic identity of the larvae and the flies. The larvae neither damage floral parts nor cause gall formation, but feed on pollen grains by sucking out their content. The larvae move out of the flowers before decomposition starts. Carebara ants steal developing larvae from flowers but do not contribute to pollination.• More than one kind of myiophily is present in Aspidistra. Brood site pollination was documented for the first time in Aspidistra. The pollination system of A. xuansonensis differs from other kinds of brood site pollination in the exit of the larvae prior to the decomposition of floral parts. © 2014 Botanical Society of America, Inc.

  7. North American pollinosis due to insect-pollinated plants.

    Science.gov (United States)

    Lewis, W H; Vinay, P

    1979-05-01

    In warmer regions of North America many newly introduced plants are cultivated widely and others are becoming aggresive naturalized weeds. A large number are insect-pollinated and shed considerable quantities of airborne pollen. Levels of allergenicity based on skin test data, numbers of patients having immediate hypersensitivity and localities where airborne pollen grains have been identified are presented for each genus of entomophilous plants considered incitants of pollinosis. Among the most relevant are Acacia, Brassica, Citrus, Ligustrum, Olea and Schinus.

  8. Pollinator communities in strawberry crops - variation at multiple spatial scales.

    Science.gov (United States)

    Ahrenfeldt, E J; Klatt, B K; Arildsen, J; Trandem, N; Andersson, G K S; Tscharntke, T; Smith, H G; Sigsgaard, L

    2015-08-01

    Predicting potential pollination services of wild bees in crops requires knowledge of their spatial distribution within fields. Field margins can serve as nesting and foraging habitats for wild bees and can be a source of pollinators. Regional differences in pollinator community composition may affect this spill-over of bees. We studied how regional and local differences affect the spatial distribution of wild bee species richness, activity-density and body size in crop fields. We sampled bees both from the field centre and at two different types of semi-natural field margins, grass strips and hedges, in 12 strawberry fields. The fields were distributed over four regions in Northern Europe, representing an almost 1100 km long north-south gradient. Even over this gradient, daytime temperatures during sampling did not differ significantly between regions and did therefore probably not impact bee activity. Bee species richness was higher in field margins compared with field centres independent of field size. However, there was no difference between centre and margin in body-size or activity-density. In contrast, bee activity-density increased towards the southern regions, whereas the mean body size increased towards the north. In conclusion, our study revealed a general pattern across European regions of bee diversity, but not activity-density, declining towards the field interior which suggests that the benefits of functional diversity of pollinators may be difficult to achieve through spill-over effects from margins to crop. We also identified dissimilar regional patterns in bee diversity and activity-density, which should be taken into account in conservation management.

  9. Optimization of controlled pollination in avocado (persea americana Mill., Lauraceae)

    OpenAIRE

    Alcaraz Arco, María Librada; Hormaza Urroz, José Ignacio

    2014-01-01

    Avocado has a singular synchronous protogynous dichogamy breeding system that promotes outcrossing. In this work different steps have been optimized to improve controlled pollinations in avocado in order to perform basic studies of reproductive biology and directed crosses in breeding programs. The results show that, in order to achieve successful fruit set, male flowers should be collected when all the anthers have dehisced and the pollen transferred by direct contact of the anthers with the...

  10. Crop pollination from native bees at risk from agricultural intensification

    OpenAIRE

    Kremen, Claire; Williams, Neal M.; Thorp, Robbin W.

    2002-01-01

    Ecosystem services are critical to human survival; in selected cases, maintaining these services provides a powerful argument for conserving biodiversity. Yet, the ecological and economic underpinnings of most services are poorly understood, impeding their conservation and management. For centuries, farmers have imported colonies of European honey bees (Apis mellifera) to fields and orchards for pollination services. These colonies are becoming increasingly scarce, however, because of disease...

  11. Evolutionary consequences of shifts to bird-pollination in the Australian pea-flowered legumes (Mirbelieae and Bossiaeeae).

    Science.gov (United States)

    Toon, Alicia; Cook, Lyn G; Crisp, Michael D

    2014-03-07

    Interactions with pollinators are proposed to be one of the major drivers of diversity in angiosperms. Specialised interactions with pollinators can lead to specialised floral traits, which collectively are known as a pollination syndrome. While it is thought that specialisation to a pollinator can lead to either an increase in diversity or in some cases a dead end, it is not well understood how transitions among specialised pollinators contribute to changes in diversity. Here, we use evolutionary trait reconstruction of bee-pollination and bird-pollination syndromes in Australian egg-and-bacon peas (Mirbelieae and Bossiaeeae) to test whether transitions between pollination syndromes is correlated with changes in species diversity. We also test for directionality in transitions that might be caused by selection by pollinators or by an evolutionary ratchet in which reversals to the original pollination syndrome are not possible. Trait reconstructions of Australian egg-and-bacon peas suggest that bee-pollination syndrome is the ancestral form and that there has been replicated evolution of bird-pollination syndromes. Reconstructions indicate potential reversals from bird- to bee-pollination syndromes but this is not consistent with morphology. Species diversity of bird-pollination syndrome clades is lower than that of their bee-pollination syndrome sisters.We estimated the earliest transitions from bee- to bird-pollination syndrome occurred between 30.8 Ma and 10.4 Ma. Geographical structuring of pollination syndromes was found; there were fewer bird-pollination species in the Australian southeast temperate region compared to other regions of Australia. A consistent decrease in diversification rate coincident with switches to bird pollination might be explained if greater dispersal by bird pollinators results in higher levels of connectivity among populations and reduced chances of allopatric speciation.The earliest transitions overlap with the early diversification

  12. Scarcity of ecosystem services: an experimental manipulation of declining pollination rates and its economic consequences for agriculture

    Directory of Open Access Journals (Sweden)

    Harpinder Sandhu

    2016-07-01

    Full Text Available Ecosystem services (ES such as pollination are vital for the continuous supply of food to a growing human population, but the decline in populations of insect pollinators worldwide poses a threat to food and nutritional security. Using a pollinator (honeybee exclusion approach, we evaluated the impact of pollinator scarcity on production in four brassica fields, two producing hybrid seeds and two producing open-pollinated ones. There was a clear reduction in seed yield as pollination rates declined. Open-pollinated crops produced significantly higher yields than did the hybrid ones at all pollination rates. The hybrid crops required at least 0.50 of background pollination rates to achieve maximum yield, whereas in open-pollinated crops, 0.25 pollination rates were necessary for maximum yield. The total estimated economic value of pollination services provided by honeybees to the agricultural industry in New Zealand is NZD $1.96 billion annually. This study indicates that loss of pollination services can result in significant declines in production and have serious implications for the market economy in New Zealand. Depending on the extent of honeybee population decline, and assuming that results in declining pollination services, the estimated economic loss to New Zealand agriculture could be in the range of NZD $295–728 million annually.

  13. A review of the energetics of pollination biology.

    Science.gov (United States)

    McCallum, Kimberly P; McDougall, Freya O; Seymour, Roger S

    2013-10-01

    Pollination biology is often associated with mutualistic interactions between plants and their animal pollen vectors, with energy rewards as the foundation for co-evolution. Energy is supplied as food (often nectar from flowers) or as heat (in sun-tracking or thermogenic plants). The requirements of pollinators for these resources depend on many factors, including the costs of living, locomotion, thermoregulation and behaviour, all of which are influenced by body size. These requirements are modified by the availability of energy offered by plants and environmental conditions. Endothermic insects, birds and bats are very effective, because they move faster and are more independent of environmental temperatures, than are ectothermic insects, but they are energetically costly for the plant. The body size of endothermic pollinators appears to be influenced by opposing requirements of the animals and plants. Large body size is advantageous for endotherms to retain heat. However, plants select for small body size of endotherms, as energy costs of larger size are not matched by increases in flight speed. If high energy costs of endothermy cannot be met, birds and mammals employ daily torpor, and large insects reduce the frequency of facultative endothermy. Energy uptake can be limited by the time required to absorb the energy or eliminate the excess water that comes with it. It can also be influenced by variations in climate that determine temperature and flowering season.

  14. Bee Pollination in Syagrus orinocensis (ARECACEAE in the Colombian Orinoquia

    Directory of Open Access Journals (Sweden)

    Luis Alberto Nuñez Avellaneda

    2017-05-01

    Full Text Available The pollination ecology of the Syagrus orinocensis was studied in the course of three consecutive yearly flowering seasons in a foothill forest in Casanare, Colombian Orinoco region. Syagrus orinocensis palms grow up to 10 m high and produce one to four bisexual, occasionally unisexual, inflorescences. The bisexual inflorescences bear staminate and pistillate flowers arranged in triads, whereas the unisexual inflorescences carry only staminate flowers in dyads. The inflorescences are protandric and open during daytime, remaining active for 26 days. The male phase extends for the first 15 days, which are followed by 8 days of an inactive phase; the pistillate phase lasts up to three days. The inflorescences of S. orinocencis were visited by 43 species of insects belonging to the orders Coleoptera, Hymenoptera and Diptera. The presence of anthophilous insects was primarily restricted to the male phase of anthesis, during which the visitors searched for pollen and breeding sites; those which visited inflorescences during the female phase seeked out nectar. The most effective pollinators of S. orinocencis were stingless bees (Apidae, Meliponini, as they transferred in average 83% of the pollen that reached receptive inflorescences. The presence, constancy and efficiency of stingless bees during this study constitute solid evidence of melittophily in S. orinocensis and allows us to propose criteria to redefine this pollination syndrome in Neotropical wild palms.

  15. The city as a refuge for insect pollinators.

    Science.gov (United States)

    Hall, Damon M; Camilo, Gerardo R; Tonietto, Rebecca K; Ollerton, Jeff; Ahrné, Karin; Arduser, Mike; Ascher, John S; Baldock, Katherine C R; Fowler, Robert; Frankie, Gordon; Goulson, Dave; Gunnarsson, Bengt; Hanley, Mick E; Jackson, Janet I; Langellotto, Gail; Lowenstein, David; Minor, Emily S; Philpott, Stacy M; Potts, Simon G; Sirohi, Muzafar H; Spevak, Edward M; Stone, Graham N; Threlfall, Caragh G

    2017-02-01

    Research on urban insect pollinators is changing views on the biological value and ecological importance of cities. The abundance and diversity of native bee species in urban landscapes that are absent in nearby rural lands evidence the biological value and ecological importance of cities and have implications for biodiversity conservation. Lagging behind this revised image of the city are urban conservation programs that historically have invested in education and outreach rather than programs designed to achieve high-priority species conservation results. We synthesized research on urban bee species diversity and abundance to determine how urban conservation could be repositioned to better align with new views on the ecological importance of urban landscapes. Due to insect pollinators' relatively small functional requirements-habitat range, life cycle, and nesting behavior-relative to larger mammals, we argue that pollinators put high-priority and high-impact urban conservation within reach. In a rapidly urbanizing world, transforming how environmental managers view the city can improve citizen engagement and contribute to the development of more sustainable urbanization. © 2016 The Authors. Conservation Biology published by Wiley Periodicals, Inc. on behalf of Society for Conservation Biology.

  16. Integration and macroevolutionary patterns in the pollination biology of conifers.

    Science.gov (United States)

    Leslie, Andrew B; Beaulieu, Jeremy M; Crane, Peter R; Knopf, Patrick; Donoghue, Michael J

    2015-06-01

    Integration influences patterns of trait evolution, but the relationship between these patterns and the degree of trait integration is not well understood. To explore this further, we study a specialized pollination mechanism in conifers whose traits are linked through function but not development. This mechanism depends on interactions among three characters: pollen that is buoyant, ovules that face downward at pollination, and the production of a liquid droplet that buoyant grains float through to enter the ovule. We use a well-sampled phylogeny of conifers to test correlated evolution among these characters and specific sequences of character change. Using likelihood models of character evolution, we find that pollen morphology and ovule characters evolve in a concerted manner, where the flotation mechanism breaks down irreversibly following changes in orientation or drop production. The breakdown of this functional constraint, which may be facilitated by the lack of developmental integration among the constituent traits, is associated with increased trait variation and more diverse pollination strategies. Although this functional "release" increases diversity in some ways, the irreversible way in which the flotation mechanism is lost may eventually result in its complete disappearance from seed plant reproductive biology. © 2015 The Author(s). Evolution © 2015 The Society for the Study of Evolution.

  17. Stingless bees further improve apple pollination and production

    Directory of Open Access Journals (Sweden)

    Blandina Felipe Viana

    2014-10-01

    Full Text Available The use of Africanised honeybee (Apis mellifera scutellata Lepeletier hives to increase pollination success in apple orchards is a widespread practice. However, this study is the first to investigate the number of honeybee hives ha-1 required to increase the production of fruits and seeds as well as the potential contribution of the stingless bee Mandaçaia (Melipona quadrifasciata anthidioides Lepeletier. We performed tests in a 43-ha apple orchard located in the municipality of Ibicoara (13º24’50.7’’S and 41º17’7.4’’W in Chapada Diamantina, State of Bahia, Brazil. In 2011, fruits from the Eva variety set six seeds on average, and neither a greater number of hives (from 7 to 11 hives ha-1 nor a greater number of pollen collectors at the honeybee hives displayed general effects on the seed number. Without wild pollinators, seven Africanised honeybee hives ha-1 with pollen collectors is currently the best option for apple producers because no further increase in the seed number was observed with higher hive densities. In 2012, supplementation with both stingless bees (12 hives ha-1 and Africanised honeybees (7 hives ha-1 provided higher seed and fruit production than supplementation with honeybees (7 hives ha-1 alone. Therefore, the stingless bee can improve the performance of honeybee as a pollinator of apple flowers, since the presence of both of these bees results in increases in apple fruit and seed number.

  18. Diversity of Pollinator Insects in Relation to Seed Set of Mustard (Brassica rapa L.: Cruciferae

    Directory of Open Access Journals (Sweden)

    TRI ATMOWIDI

    2007-12-01

    Full Text Available Pollinators provide key services to both natural and agricultural ecosystems. Agricultural productivity depends, in part, on pollinator populations from adjacent seminatural habitats. Here we analysed the diversity of pollinator insects and its effect to seed set of mustard (Brassica rapa planted in agricultural ecosystem near the Gunung Halimun-Salak National Park, West Java. At least 19 species of insects pollinated the mustard, and three species, i.e. Apis cerana, Ceratina sp., and Apis dorsata showed a high abundance. The higher abundance and species richness of pollinators occurred at 08.30-10.30 am and the diversity was related to the number of flowering plants. Insect pollinations increased the number of pods, seeds per pod, seed weights per plant, and seed germination.

  19. Agricultural Policies Exacerbate Honeybee Pollination Service Supply-Demand Mismatches Across Europe

    Science.gov (United States)

    Breeze, Tom D.; Vaissière, Bernard E.; Bommarco, Riccardo; Petanidou, Theodora; Seraphides, Nicos; Kozák, Lajos; Scheper, Jeroen; Biesmeijer, Jacobus C.; Kleijn, David; Gyldenkærne, Steen; Moretti, Marco; Holzschuh, Andrea; Steffan-Dewenter, Ingolf; Stout, Jane C.; Pärtel, Meelis; Zobel, Martin; Potts, Simon G.

    2014-01-01

    Declines in insect pollinators across Europe have raised concerns about the supply of pollination services to agriculture. Simultaneously, EU agricultural and biofuel policies have encouraged substantial growth in the cultivated area of insect pollinated crops across the continent. Using data from 41 European countries, this study demonstrates that the recommended number of honeybees required to provide crop pollination across Europe has risen 4.9 times as fast as honeybee stocks between 2005 and 2010. Consequently, honeybee stocks were insufficient to supply >90% of demands in 22 countries studied. These findings raise concerns about the capacity of many countries to cope with major losses of wild pollinators and highlight numerous critical gaps in current understanding of pollination service supplies and demands, pointing to a pressing need for further research into this issue. PMID:24421873

  20. Impact of Bee Species and Plant Density on Alfalfa Pollination and Potential for Gene Flow

    Directory of Open Access Journals (Sweden)

    Johanne Brunet

    2010-01-01

    Full Text Available In outcrossing crops like alfalfa, various bee species can contribute to pollination and gene flow in seed production fields. With the increasing use of transgenic crops, it becomes important to determine the role of these distinct pollinators on alfalfa pollination and gene flow. The current study examines the relative contribution of honeybees, three bumble bee species, and three solitary bee species to pollination and gene flow in alfalfa. Two wild solitary bee species and one wild bumble bee species were best at tripping flowers, while the two managed pollinators commonly used in alfalfa seed production, honeybees and leaf cutting bees, had the lowest tripping rate. Honeybees had the greatest potential for gene flow and risk of transgene escape relative to the other pollinators. For honeybees, gene flow and risk of transgene escape were not affected by plant density although for the three bumble bee species gene flow and risk of transgene escape were the greatest in high-density fields.

  1. Plant-pollinator coextinctions and the loss of plant functional and phylogenetic diversity.

    Science.gov (United States)

    Vieira, Marcos Costa; Cianciaruso, Marcus Vinicius; Almeida-Neto, Mário

    2013-01-01

    Plant-pollinator coextinctions are likely to become more frequent as habitat alteration and climate change continue to threaten pollinators. The consequences of the resulting collapse of plant communities will depend partly on how quickly plant functional and phylogenetic diversity decline following pollinator extinctions. We investigated the functional and phylogenetic consequences of pollinator extinctions by simulating coextinctions in seven plant-pollinator networks coupled with independent data on plant phylogeny and functional traits. Declines in plant functional diversity were slower than expected under a scenario of random extinctions, while phylogenetic diversity often decreased faster than expected by chance. Our results show that plant functional diversity was relatively robust to plant-pollinator coextinctions, despite the underlying rapid loss of evolutionary history. Thus, our study suggests the possibility of uncoupled responses of functional and phylogenetic diversity to species coextinctions, highlighting the importance of considering both dimensions of biodiversity explicitly in ecological studies and when planning for the conservation of species and interactions.

  2. Plant-Pollinator Coextinctions and the Loss of Plant Functional and Phylogenetic Diversity

    Science.gov (United States)

    Vieira, Marcos Costa; Cianciaruso, Marcus Vinicius; Almeida-Neto, Mário

    2013-01-01

    Plant-pollinator coextinctions are likely to become more frequent as habitat alteration and climate change continue to threaten pollinators. The consequences of the resulting collapse of plant communities will depend partly on how quickly plant functional and phylogenetic diversity decline following pollinator extinctions. We investigated the functional and phylogenetic consequences of pollinator extinctions by simulating coextinctions in seven plant-pollinator networks coupled with independent data on plant phylogeny and functional traits. Declines in plant functional diversity were slower than expected under a scenario of random extinctions, while phylogenetic diversity often decreased faster than expected by chance. Our results show that plant functional diversity was relatively robust to plant-pollinator coextinctions, despite the underlying rapid loss of evolutionary history. Thus, our study suggests the possibility of uncoupled responses of functional and phylogenetic diversity to species coextinctions, highlighting the importance of considering both dimensions of biodiversity explicitly in ecological studies and when planning for the conservation of species and interactions. PMID:24312281

  3. Spatial planning of wind turbines

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-01-01

    This paper proposes guidelines for spatial planning for wind power, based on experience with spatial planning in Belgium, Denmark, France and the Netherlands. In addition experiences from Germany and Ireland have been used. This guidelines quotes all decisive criteria for successful implementation of wind energy: landscape integration, stakeholders involvement, noise and distance from buildings. (author)

  4. Status of local planning for wind turbines. Vol. 2: Jutland. Wind turbines - January 1997

    International Nuclear Information System (INIS)

    Information on the status of individual municipalities regarding wind turbine power plans, the content of the plans themselves, key figures on existing wind turbines for each municipality, overall plans for wind power development and key figures for development of wind power in Jutland - in addition to maps and lists of local authorities with either a high or a low coverage of electric power by wind turbines either now or in the future - are found in this volume. (EG)

  5. The costs and benefits of pollinator dependence: empirically-based simulations predict raspberry fruit quality.

    Science.gov (United States)

    Sáez, Agustín; Morales, Juan M; Morales, Carolina L; Harder, Lawrence D; Aizen, Marcelo A

    2018-03-24

    Globally, agriculture increasingly depends on pollinators to produce many seed and fruit crops. However, what constitutes optimal pollination service for pollinator-dependent crops remains unanswered. We developed a simulation model to identify the optimal pollination service that maximizes fruit quality in crops. The model depicts the pollination (i.e. autonomous self-fertilization, pollen deposition) and post-pollination (i.e. pollen germination, and time from germination to ovule fertilization) processes leading to fruit and seed set and allows for negative flower-pollinator interactions, specifically pistil damage. We parameterized and validated the model based on empirical observations of commercial raspberry in western Argentina. To assess the effects of pollination intensity for fruit production, we conducted simulations over a range of visit number per flower by the two primary managed pollinators worldwide, Apis mellifera and Bombus terrestris. Simulations identified that ~15-35 visits per flower by A. mellifera or ~10-20 visits by B. terrestris provide adequate pollination and maximize raspberry fruit quality (i.e. estimated as the proportion of ovules that develop into drupelets). Visits in excess of these optima reduce simulated fruit quality, and flowers receiving > 670 honey-bee visits or > 470 bumble-bee visits would produce fruits of poorer quality than those receiving no bee visits. The simulations generated consistent, unbiased predictions of fruit quality for 12 raspberry fields. This model could be adapted easily to other animal-pollinated crops and used to guide efficient pollinator management in any agro-ecosystem. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  6. Selenium Toxicity to Honey Bee (Apis mellifera L.) Pollinators: Effects on Behaviors and Survival

    OpenAIRE

    Hladun, Kristen R.; Smith, Brian H.; Mustard, Julie A.; Morton, Ray R.; Trumble, John T.

    2012-01-01

    We know very little about how soil-borne pollutants such as selenium (Se) can impact pollinators, even though Se has contaminated soils and plants in areas where insect pollination can be critical to the functioning of both agricultural and natural ecosystems. Se can be biotransferred throughout the food web, but few studies have examined its effects on the insects that feed on Se-accumulating plants, particularly pollinators. In laboratory bioassays, we used proboscis extension reflex (PER) ...

  7. Floral traits driving reproductive isolation of two co-flowering taxa that share vertebrate pollinators

    Science.gov (United States)

    Queiroz, Joel A.; Quirino, Zelma G. M.; Machado, Isabel C.

    2015-01-01

    Floral attributes evolve in response to frequent and efficient pollinators, which are potentially important drivers of floral diversification and reproductive isolation. In this context, we asked, how do flowers evolve in a bat–hummingbird pollination system? Hence, we investigated the pollination ecology of two co-flowering Ipomoea taxa (I. marcellia and I. aff. marcellia) pollinated by bats and hummingbirds, and factors favouring reproductive isolation and pollinator sharing in these plants. To identify the most important drivers of reproductive isolation, we compared the flowers of the two Ipomoea taxa in terms of morphometry, anthesis and nectar production. Pollinator services were assessed using frequency of visits, fruit set and the number of seeds per fruit after visits. The studied Ipomoea taxa differed in corolla size and width, beginning and duration of anthesis, and nectar attributes. However, they shared the same diurnal and nocturnal visitors. The hummingbird Heliomaster squamosus was more frequent in I. marcellia (1.90 visits h−1) than in I. aff. marcellia (0.57 visits h−1), whereas glossophagine bats showed similar visit rates in both taxa (I. marcellia: 0.57 visits h−1 and I. aff. marcellia: 0.64 visits h−1). Bat pollination was more efficient in I. aff. marcellia, whereas pollination by hummingbirds was more efficient in I. marcellia. Differences in floral attributes between Ipomoea taxa, especially related to the anthesis period, length of floral parts and floral arrangement in the inflorescence, favour reproductive isolation from congeners through differential pollen placement on pollinators. This bat–hummingbird pollination system seems to be advantageous in the study area, where the availability of pollinators and floral resources changes considerably throughout the year, mainly as a result of rainfall seasonality. This interaction is beneficial for both sides, as it maximizes the number of potential pollen vectors for plants and

  8. Native insect pollinators in Apple orchards under different management practices in the Kashmir Valley

    Directory of Open Access Journals (Sweden)

    Muzaffar Ahmad Ganie

    2013-12-01

    Full Text Available It is now clear that over use of pesticides and intensive management of orchards can lead to drastic declines in apple pollinator abundance and crop failures. During the period of study a grower’s survey was conducted to know about knowledge of farmers on native insect pollinators, pollinator management practices, their perceptions of the importance and utility of native pollinators, and their attitudes regarding pesticide application. Despite of having significant knowledge of managed pollination, only few farmers (2% adopted supplementary methods of pollination (renting honey bee colonies, hand pollination etc.. In Pulwama, 60% of farmers had knowledge about native insect pollinators and 40% did not have any idea of native pollinators and in case of Shopian, the figures were fifty-fifty i.e. 50% had knowledge about native insect pollinators and 50% were unaware. During the period of investigation, native insect pollinators were sampled from different apple orchards under different management systems in early spring during apple flowering. A total of 17 species of insect pollinators belonging to 11 families and 3 orders_ Hymenoptera, Diptera and Lepidoptera registered their occurrence at all the studied apple orchards of the Kashmir Valley. At all the study sites i.e. apple orchards under different management systems, family Halictidae and Empididae registered their presence as dominant groups. The % family contribution of the former at different orchard types decreased with increase in the intensity of the management system and the % family contribution of the later however, showed a direct relationship with the management system found, i.e. the more intense the system, the more abundant was the group. Other groups in general did not show any greater differences in abundances at different sites studied.

  9. World Wind

    Data.gov (United States)

    National Aeronautics and Space Administration — World Wind allows any user to zoom from satellite altitude into any place on Earth, leveraging high resolution LandSat imagery and SRTM elevation data to experience...

  10. Are there pollination syndromes in the Australian epacrids (Ericaceae: Styphelioideae)? A novel statistical method to identify key floral traits per syndrome.

    Science.gov (United States)

    Johnson, Karen A

    2013-07-01

    Convergent floral traits hypothesized as attracting particular pollinators are known as pollination syndromes. Floral diversity suggests that the Australian epacrid flora may be adapted to pollinator type. Currently there are empirical data on the pollination systems for 87 species (approx. 15 % of Australian epacrids). This provides an opportunity to test for pollination syndromes and their important morphological traits in an iconic element of the Australian flora. Data on epacrid-pollinator relationships were obtained from published literature and field observation. A multivariate approach was used to test whether epacrid floral attributes related to pollinator profiles. Statistical classification was then used to rank floral attributes according to their predictive value. Data sets excluding mixed pollination systems were used to test the predictive power of statistical classification to identify pollination models. Floral attributes are correlated with bird, fly and bee pollination. Using floral attributes identified as correlating with pollinator type, bird pollination is classified with 86 % accuracy, red flowers being the most important predictor. Fly and bee pollination are classified with 78 and 69 % accuracy, but have a lack of individually important floral predictors. Excluding mixed pollination systems improved the accuracy of the prediction of both bee and fly pollination systems. Although most epacrids have