WorldWideScience

Sample records for honeybee pollination efficiency

  1. 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 ...

  2. Eficiência polinizadora de Apis mellifera L. e polinização entomófila em pimentão 'Cascadura Ikeda' Pollination efficiency of honeybees and entomophilous pollination in sweet pepper 'Cascadura Ikeda'

    Directory of Open Access Journals (Sweden)

    Luiz Roberto Ribeiro Faria Júnior

    2008-01-01

    visited by insects; (2 caged plots; (3 caged plots containing a hive of honeybees. Twelve species of insects visited the flowers. Exomalopsis spp. (Hymenoptera, Apidae were the commonest ones (53,9% of visits. Fruits yielded in treatments (1 and (3 were heavier, presented higher diameter, thicker pericarp and more seeds per fruit than fruits in treatment (2. Results showed that fruits from insect pollinated plots presented better quality. Honeybeesas as pollinators were efficient as the other insects.

  3. Comparison of nectar foraging efficiency in the Cape honeybee ...

    African Journals Online (AJOL)

    1987-03-17

    Mar 17, 1987 ... Comparison of nectar foraging efficiency in the Cape honeybee, Apis mellifera capensis Escholtz, and the African honeybee, Apis mellifera adansonii Latreille,. , in the western Cape Province. P.V. W-Worswick*. Department of Zoology, University of Cape Town, Rondebosch 7700 Republic of South Africa.

  4. The endangered Iris atropurpurea (Iridaceae) in Israel: honey-bees, night-sheltering male bees and female solitary bees as pollinators

    Science.gov (United States)

    Watts, Stella; Sapir, Yuval; Segal, Bosmat; Dafni, Amots

    2013-01-01

    Background and Aims The coastal plain of Israel hosts the last few remaining populations of the endemic Iris atropurpurea (Iridaceae), a Red List species of high conservation priority. The flowers offer no nectar reward. Here the role of night-sheltering male solitary bees, honey-bees and female solitary bees as pollinators of I. atropurpurea is documented. Methods Breeding system, floral longevity, stigma receptivity, visitation rates, pollen loads, pollen deposition and removal and fruit- and seed-set were investigated. Key Results The main wild pollinators of this plant are male eucerine bees, and to a lesser extent, but with the potential to transfer pollen, female solitary bees. Honey-bees were found to be frequent diurnal visitors; they removed large quantities of pollen and were as effective as male sheltering bees at pollinating this species. The low density of pollen carried by male solitary bees was attributed to grooming activities, pollen displacement when bees aggregated together in flowers and pollen depletion by honey-bees. In the population free of honey-bee hives, male bees carried significantly more pollen grains on their bodies. Results from pollen analysis and pollen deposited on stigmas suggest that inadequate pollination may be an important factor limiting fruit-set. In the presence of honey-bees, eucerine bees were low removal–low deposition pollinators, whereas honey-bees were high removal–low deposition pollinators, because they removed large amounts into corbiculae and deposited relatively little onto receptive stigmas. Conclusions Even though overall, both bee taxa were equally effective pollinators, we suggest that honey-bees have the potential to reduce the amount of pollen available for plant reproduction, and to reduce the amount of resources available to solitary bee communities. The results of this study have potential implications for the conservation of this highly endangered plant species if hives are permitted inside

  5. A novel method for assessing risks to pollinators from plant protection products using honeybees as a model species.

    Science.gov (United States)

    Barmaz, Stefania; Potts, Simon G; Vighi, Marco

    2010-10-01

    Pollination is one of the most important ecosystem services in agroecosystems and supports food production. Pollinators are potentially at risk being exposed to pesticides and the main route of exposure is direct contact, in some cases ingestion, of contaminated materials such as pollen, nectar, flowers and foliage. To date there are no suitable methods for predicting pesticide exposure for pollinators, therefore official procedures to assess pesticide risk are based on a Hazard Quotient. Here we develop a procedure to assess exposure and risk for pollinators based on the foraging behaviour of honeybees (Apis mellifera) and using this species as indicator representative of pollinating insects. The method was applied in 13 European field sites with different climatic, landscape and land use characteristics. The level of risk during the crop growing season was evaluated as a function of the active ingredients used and application regime. Risk levels were primarily determined by the agronomic practices employed (i.e. crop type, pest control method, pesticide use), and there was a clear temporal partitioning of risks through time. Generally the risk was higher in sites cultivated with permanent crops, such as vineyard and olive, than in annual crops, such as cereals and oil seed rape. The greatest level of risk is generally found at the beginning of the growing season for annual crops and later in June-July for permanent crops.

  6. 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.

  7. Agricultural policies exacerbate honeybee pollination service supply-demand mismatches across Europe

    NARCIS (Netherlands)

    Breeze, T.; Vaissiere, B.E.; Bommarco, R.; Petanidou, T.; Seraphides, N.; Kozak, L.; Scheper, J.A.; Biesmeijer, J.C.; Kleijn, D.; Gyldenkaerne, S.

    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

  8. Firm efficiency and returns-to-scale in the honey bee pollination services industry

    Science.gov (United States)

    Honeybees are well-known for producing honey, but they also provide critical ecosystem services through pollination (Goulson, 2003; Potts et al., 2010; Ványi et al., 2012). This pollination service is vital to the production of many cash crops, on which the U.S. agricultural sector depends (Aizen an...

  9. Food for honeybees? Pollinators and seed set of Anthyllis barba-jovis L. (Fabaceae in arid coastal areas of the Mediterranean basin

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    Giovanni Benelli

    2017-07-01

    Full Text Available Abundance and diversity of insect pollinators are declining in many ecosystems worldwide. The abundance and diversity of wild and managed bees are related to the availability of continuous floral resources. In particular, in Mediterranean basin countries, the presence of wildflower spots enhances the establishment of social Apoidea, since coastal regions are usually characterized by pollen and nectar shortage in early spring and late summer. Anthyllis barba-jovis produces both nectar and pollen as important food source for bees helping them to overcome early spring period food shortage. We investigated flowering, seed set, and pollinator diversity of A. barba-jovis in arid coastal environments of the Mediterranean basin. Pollinator abundance reached a maximum in early April. Honeybees were the most common pollinators followed by bumblebees and solitary bees. Plants prevented from entomophilous pollination showed inbreeding depression with a strong decrease in seed-set. To the best of our knowledge, this is the first report on pollination ecology of A. barba-jovis.

  10. 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 ...

  11. 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.

  12. Pollination

    OpenAIRE

    Kühn, Nathalie; Arce-Johnson, Patricio

    2012-01-01

    Berry formation is the process of ovary conversion into a functional fruit, and is characterized by abrupt changes in the content of several phytohormones, associated with pollination and fertilization. Much effort has been made in order to improve our understanding of berry development, particularly from veraison to post-harvest time. However, the period of berry formation has been poorly investigated, despite its importance. Phytohormones are involved in the control of fruit formation; henc...

  13. Pollination

    Science.gov (United States)

    Kühn, Nathalie; Arce-Johnson, Patricio

    2012-01-01

    Berry formation is the process of ovary conversion into a functional fruit, and is characterized by abrupt changes in the content of several phytohormones, associated with pollination and fertilization. Much effort has been made in order to improve our understanding of berry development, particularly from veraison to post-harvest time. However, the period of berry formation has been poorly investigated, despite its importance. Phytohormones are involved in the control of fruit formation; hence it is important to understand the regulation of their content at this stage. Grapevine is an excellent fleshy-fruit plant model since its fruits have particularities that differentiate them from those of commonly studied organisms. For instance, berries are prepared to cope with stress by producing several antioxidants and they are non-climacteric fruits. Also its genome is fully sequenced, which allows to identify genes involved in developmental processes. In grapevine, no link has been established between pollination and phytohormone biosynthesis, until recently. Here we highlight relevant findings regarding pollination effect on gene expression related to phytohormone biosynthesis, and present results showing how quickly this effect is achieved. PMID:22301957

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

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    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.

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

    OpenAIRE

    Wu, Yun; Li, Qing‐Jun

    2017-01-01

    Abstract 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 ...

  16. Pollination efficiency of Apis mellifera Linnaeus, 1758 (Hymenoptera, Apidae) on the monoecious plants Jatropha mollissima (Pohl) Baill. and Jatropha mutabilis (Pohl) Baill. (Euphorbiaceae) in a semi-arid Caatinga area, northeastern Brazil.

    Science.gov (United States)

    Neves, E L; Viana, B F

    2011-02-01

    Previous studies have shown the superior competitive ability of honeybees compared with native bees in the exploitation of floral resources and nesting sites besides their low efficiency in pollinating native plant species. However, there is little evidence of the effect of this invading species on autochthonous plant populations in natural environments. Thus experiments were performed to test the pollination efficiency of honeybees in two species of Jatropha (Euphorbiaceae), J. mollissima (Pohl) Baill. and J. mutabilis (Pohl) Baill., after a single flower visitation. Samplings were carried out between March and April 2006 in a hyperxerophilous shrub-arboreal Caatinga at Estação Biológica de Canudos, Bahia (9º 56´ 34" S, 38º 59´ 17" W), the property of Fundação Biodiversitas. Apis mellifera was efficient at pollinating J. mollissima (100%) and J. mutabilis (85%). This high efficiency may be explained by 1) the simple floral characteristics of both plant species, which facilitate access to the sexual organs of the plant; and 2) the body size of A. mellifera that fits the flower's dimensions.

  17. MtDNA COI-COII marker and drone congregation area: an efficient method to establish and monitor honeybee (Apis mellifera L.) conservation centres.

    Science.gov (United States)

    Bertrand, Bénédicte; Alburaki, Mohamed; Legout, Hélène; Moulin, Sibyle; Mougel, Florence; Garnery, Lionel

    2015-05-01

    Honeybee subspecies have been affected by human activities in Europe over the past few decades. One such example is the importation of nonlocal subspecies of bees which has had an adverse impact on the geographical repartition and subsequently on the genetic diversity of the black honeybee Apis mellifera mellifera. To restore the original diversity of this local honeybee subspecies, different conservation centres were set up in Europe. In this study, we established a black honeybee conservation centre Conservatoire de l'Abeille Noire d'Ile de France (CANIF) in the region of Ile-de-France, France. CANIF's honeybee colonies were intensively studied over a 3-year period. This study included a drone congregation area (DCA) located in the conservation centre. MtDNA COI-COII marker was used to evaluate the genetic diversity of CANIF's honeybee populations and the drones found and collected from the DCA. The same marker (mtDNA) was used to estimate the interactions and the haplotype frequency between CANIF's honeybee populations and 10 surrounding honeybee apiaries located outside of the CANIF. Our results indicate that the colonies of the conservation centre and the drones of the DCA show similar stable profiles compared to the surrounding populations with lower level of introgression. The mtDNA marker used on both DCA and colonies of the conservation centre seems to be an efficient approach to monitor and maintain the genetic diversity of the protected honeybee populations. © 2014 John Wiley & Sons Ltd.

  18. The efficiency of bees in pollinating ephemeral flowers of Jacquemontia bracteosa (Convolvulaceae

    Directory of Open Access Journals (Sweden)

    Sílvia K. D. Santos

    Full Text Available ABSTRACT The family Convolvulaceae is widely distributed in tropical regions, mainly in open areas. Convolvulaceae flowers are characterized mainly by being beautiful and ephemeral, attracting many flower visitors that belong to different taxonomic groups. This work aimed to investigate the interactions between insects and flowers of Jacquemontia bracteosa (Convolvulaceae, focusing on the pollination efficiency, in an area in the Brazilian semiarid. From November 2011 to October 2012, floral biology of J. bracteosa was investigated as well as the flower visit frequency, behavior, and morphology of floral visitors. The flowers of J. bracteosa are white, showy and open early in the morning, lasting less than 12 hours, with fruiting occurring both by selfing and outcrossing fecundation. A total of 337 specimens insects were collected on J. bracteosa flowers during the field observations. The Neotropical bee, Ancyloscelis apiformis, was considered the most efficient pollinator of J. bracteosa. This bee showed appropriate behavior, high frequency (64% of the total sample, and was constant on the flowers. Furthermore, they arrived soon when the flowers began to open and presented 90% of efficiency in tests of flower pollination of J. bracteosa. Other native bee species also visited the flowers of J. bracteosa and may be considered potential pollinators because they presented behavior and morphology compatible with the flowers. This study suggests that maintenance of weeds or ruderal plants, especially those that also have ornamental potential in anthropic area, may be an option for the preservation of local native pollinators, which are threatened by environmental degradation.

  19. Proteomics Improves the New Understanding of Honeybee Biology.

    Science.gov (United States)

    Hora, Zewdu Ararso; Altaye, Solomon Zewdu; Wubie, Abebe Jemberie; Li, Jianke

    2018-04-11

    The honeybee is one of the most valuable insect pollinators, playing a key role in pollinating wild vegetation and agricultural crops, with significant contribution to the world's food production. Although honeybees have long been studied as model for social evolution, honeybee biology at the molecular level remained poorly understood until the year 2006. With the availability of the honeybee genome sequence and technological advancements in protein separation, mass spectrometry, and bioinformatics, aspects of honeybee biology such as developmental biology, physiology, behavior, neurobiology, and immunology have been explored to new depths at molecular and biochemical levels. This Review comprehensively summarizes the recent progress in honeybee biology using proteomics to study developmental physiology, task transition, and physiological changes in some of the organs, tissues, and cells based on achievements from the authors' laboratory in this field. The research advances of honeybee proteomics provide new insights for understanding of honeybee biology and future research directions.

  20. Foraging dynamics and pollination efficiency of Apis mellifera and Xylocopa olivacea on Luffa aegyptiaca Mill (Cucurbitaceae) in southern Ghana

    OpenAIRE

    Mensah, Ben

    2011-01-01

    As a result of different levels of pollination efficiency of pollinators, knowledge on appropriate pollinators of a plant has become important, especially in the management and conservation of both the pollinators and the plants. In this study, the pollination efficiency of Apis mellifera and Xylocopa olivacea, important pollinators of Luffa aegyptiaca, were assessed in the southern coastal part of Ghana from June 2009 to September 2010. Pollination efficiency of A. mellifera and X. olivacea ...

  1. Efficiency of local Indonesia honey bees (Apis cerana L.) and stingless bee (Trigona iridipennis) on tomato (Lycopersicon esculentum Mill.) pollination.

    Science.gov (United States)

    Putra, Ramadhani Eka; Kinasih, Ida

    2014-01-01

    Tomato (Lycopersicon esculentum Mill.) is considered as one of major agricultural commodity of Indonesia farming. However, monthly production is unstable due to lack of pollination services. Common pollinator agent of tomatoes is bumblebees which is unsuitable for tropical climate of Indonesia and the possibility of alteration of local wild plant interaction with their pollinator. Indonesia is rich with wild bees and some of the species already domesticated for years with prospect as pollinating agent for tomatoes. This research aimed to assess the efficiency of local honey bee (Apis cerana L.) and stingless bee (Trigona iridipennis), as pollinator of tomato. During this research, total visitation rate and total numbers of pollinated flowers by honey bee and stingless bee were compared between them with bagged flowers as control. Total fruit production, average weight and size also measured in order to correlated pollination efficiency with quantity and quality of fruit produced. Result of this research showed that A. cerana has slightly higher rate of visitation (p>0.05) and significantly shorter handling time (p tomato flowers. However, honey bee pollinated tomato flowers more efficient pollinator than stingless bee (80.3 and 70.2% efficiency, respectively; p tomatoes were similar (p>0.05). Based on the results, it is concluded that the use of Apis cerana and Trigona spp., for pollinating tomatoes in tropical climates could be an alternative to the use of non-native Apis mellifera and bumblebees (Bombus spp.). However, more researches are needed to evaluate the cost/benefit on large-scale farming and greenhouse pollination using both bees against other bee species and pollination methods.

  2. Foraging dynamics and pollination efficiency of Apis mellifera and Xylocopa olivacea on Luffa aegyptiaca Mill (Cucurbitaceae in southern Ghana

    Directory of Open Access Journals (Sweden)

    Mensah, Ben

    2011-05-01

    Full Text Available As a result of different levels of pollination efficiency of pollinators, knowledge on appropriate pollinators of a plant has become important, especially in the management and conservation of both the pollinators and the plants. In this study, the pollination efficiency of Apis mellifera and Xylocopa olivacea, important pollinators of Luffa aegyptiaca, were assessed in the southern coastal part of Ghana from June 2009 to September 2010. Pollination efficiency of A. mellifera and X. olivacea was estimated in terms of fruit set and fruit size. Further, data on daily and seasonal nectar dynamics of Luffa aegyptiaca were collected. In the early mornings (0600-0700, X. olivacea was the most frequent visitor (0.47 min-1 on the female flowers compared to A. mellifera (0.13 min-1. The mean nectar (sugar concentration in the dry season was 36.58 ± 0.55 %, which was higher than the 34.03 ± 0.38 % obtained for the rainy season (F = 14.986; df = 2; P χ2 = 14.33, df = 1, P X. olivacea had a mean weight of 428.7g and were 1.5 times heavier than fruits from flowers visited by A. mellifera (286.76 g. X. olivacea was more efficient than A. mellifera in terms of number of fruit set per single visit. This study has provided some knowledge on pollination ecology of L. aegyptiaca, which can be exploited to improve fruit production in commercially grown vine crops.

  3. How to efficiently obtain accurate estimates of flower visitation rates by pollinators

    NARCIS (Netherlands)

    Fijen, Thijs P.M.; Kleijn, David

    2017-01-01

    Regional declines in insect pollinators have raised concerns about crop pollination. Many pollinator studies use visitation rate (pollinators/time) as a proxy for the quality of crop pollination. Visitation rate estimates are based on observation durations that vary significantly between studies.

  4. Honeybees tolerate cyanogenic glucosides from clover nectar and flowers

    DEFF Research Database (Denmark)

    Lecocq, Antoine; Green, Amelia Ann; Pinheiro de Castro, Érika Cristina

    2018-01-01

    Honeybees (Apis mellifera) pollinate flowers and collect nectar from many important crops. White clover (Trifolium repens) is widely grown as a temperate forage crop, and requires honeybee pollination for seed set. In this study, using a quantitative LC-MS (Liquid Chromatography-Mass Spectrometry...... indicates that plant secondary metabolites found in nectar may protect pollinators from disease or predators. In a laboratory survival study with chronic feeding of secondary metabolites, we show that honeybees can ingest the cyanogenic glucosides linamarin and amygdalin at naturally occurring...

  5. Firm Efficiency and Returns-to-Scale in the Honey Bee Pollination Services Industry.

    Science.gov (United States)

    Jones Ritten, Chian; Peck, Dannele; Ehmke, Mariah; Patalee, M A Buddhika

    2018-04-03

    While the demand for pollination services have been increasing, continued declines in honey bee, Apis mellifera L. (Hymenoptera: Apidae), colonies have put the cropping sector and the broader health of agro-ecosystems at risk. Economic factors may play a role in dwindling honey bee colony supply in the United States, but have not been extensively studied. Using data envelopment analysis (DEA), we measure technical efficiency, returns to scale, and factors influencing the efficiency of those apiaries in the northern Rocky Mountain region participating in the pollination services market. We find that, although over 25% of apiaries are technically efficient, many experience either increasing or decreasing returns to scale. Smaller apiaries (under 80 colonies) experience increasing returns to scale, but a lack of available financing may hinder them from achieving economically sustainable colony levels. Larger apiaries (over 1,000 colonies) experience decreasing returns to scale. Those beekeepers may have economic incentivizes to decrease colony numbers. Using a double bootstrap method, we find that apiary location and off-farm employment influence apiary technical efficiency. Apiaries in Wyoming are found to be more efficient than those in Utah or Montana. Further, engagement in off-farm employment increases an apiary's technical efficiency. The combined effects of efficiency gains through off-farm employment and diseconomies of scale may explain, in part, the historical decline in honey bee numbers.

  6. Nosema Tolerant Honeybees (Apis mellifera) Escape Parasitic Manipulation of Apoptosis

    DEFF Research Database (Denmark)

    Kurze, Christoph; Le Conte, Yves; Dussaubat, Claudia

    2015-01-01

    conducted three inoculation experiments to investigate in the apoptotic respond during infection with the intracellular gut pathogen Nosema ceranae, which is considered as potential global threat to the honeybee (Apis mellifera) and other bee pollinators, in sensitive and tolerant honeybees. To explore...

  7. Evidence of trapline foraging in honeybees.

    Science.gov (United States)

    Buatois, Alexis; Lihoreau, Mathieu

    2016-08-15

    Central-place foragers exploiting floral resources often use multi-destination routes (traplines) to maximise their foraging efficiency. Recent studies on bumblebees have showed how solitary foragers can learn traplines, minimising travel costs between multiple replenishing feeding locations. Here we demonstrate a similar routing strategy in the honeybee (Apis mellifera), a major pollinator known to recruit nestmates to discovered food resources. Individual honeybees trained to collect sucrose solution from four artificial flowers arranged within 10 m of the hive location developed repeatable visitation sequences both in the laboratory and in the field. A 10-fold increase of between-flower distances considerably intensified this routing behaviour, with bees establishing more stable and more efficient routes at larger spatial scales. In these advanced social insects, trapline foraging may complement cooperative foraging for exploiting food resources near the hive (where dance recruitment is not used) or when resources are not large enough to sustain multiple foragers at once. © 2016. Published by The Company of Biologists Ltd.

  8. Pollination potential of male bumble bees (Bombus impatiens: movement patterns and pollen-transfer efficiency

    Directory of Open Access Journals (Sweden)

    James Thomson

    2010-11-01

    Full Text Available Many plant species rely on female bumble bee workers for pollen transfer. However, male bumble bees, which differ both behaviourally and morphologically from female workers, also visit many species of flowering plants and may transfer pollen differently. Males can outnumber workers on some plants, particularly those that flower late in the season. In laboratory experiments, we compared the movement patterns of male bees and female workers on an artificial flower array. We also compared the pollen transfer efficiency of males and workers foraging on Brassica rapa flowers. Males travelled between patches of flowers more often than workers, which may be an effective method for reducing geitonogamy in plants. Males also had lower foraging rates, longer flower handling time, and transferred more pollen from one B. rapa flower to the next than workers did. These caste-based differences in pollinating behaviour suggest that, under certain circumstances and on a per-visit basis, male bumble bees may be better pollen vectors than female foragers. Furthermore, our results emphasize the need to avoid species-wide generalizations of pollinator effectiveness.

  9. Nest establishment, pollination efficiency, and reproductive success of Megachile rotundata (Hymenoptera: Megachilidae) in relation to resource availability in field enclosures.

    Science.gov (United States)

    Pitts-Singer, Theresa L; Bosch, Jordi

    2010-02-01

    The alfalfa leafcutting bee, Megachile rotundata (Fabricius), is used to pollinate alfalfa, Medicago sativa L., for seed production in the United States and Canada. It is difficult to reliably sustain commercial M. rotundata populations in the United States because of problems with disease, parasites, predators, and unexplained mortality. One possible explanation for early immature mortality is that, relative to floral availability, superfluous numbers of bees are released in alfalfa fields where resources quickly become limited. Our objective was to determine how M. rotundata density affects bee nesting, pollination efficiency, and reproductive success. Various numbers of bees were released into enclosures on an alfalfa field, but only 10-90% of released female bees established nests. Therefore, a "bee density index" was derived for each enclosure from the number of established females and number of open flowers over time. As the density index increased, significant reductions occurred in the number of pollinated flowers, number of nests, and number of cells produced per bee, as well as the percentage of cells that produced viable prepupae by summer's end and the percentage that produced adult bees. The percentage of cells resulting in early brood mortality (i.e., pollen balls) significantly increased as the density index increased. We conclude that bee nest establishment, pollination efficiency, and reproductive success are compromised when bee densities are high relative to floral resource availability. Open field studies are needed to determine commercial bee densities that result in sustainable bee populations and adequate pollination for profitable alfalfa seed production.

  10. Do Honeybees Shape the Bacterial Community Composition in Floral Nectar?

    Science.gov (United States)

    Aizenberg-Gershtein, Yana; Izhaki, Ido; Halpern, Malka

    2013-01-01

    Floral nectar is considered the most important reward animal-pollinated plants offer to attract pollinators. Here we explore whether honeybees, which act as pollinators, affect the composition of bacterial communities in the nectar. Nectar and honeybees were sampled from two plant species: Amygdalus communis and Citrus paradisi. To prevent the contact of nectar with pollinators, C. paradisi flowers were covered with net bags before blooming (covered flowers). Comparative analysis of bacterial communities in the nectar and on the honeybees was performed by the 454-pyrosequencing technique. No significant differences were found among bacterial communities in honeybees captured on the two different plant species. This resemblance may be due to the presence of dominant bacterial OTUs, closely related to the Arsenophonus genus. The bacterial communities of the nectar from the covered and uncovered C. paradisi flowers differed significantly; the bacterial communities on the honeybees differed significantly from those in the covered flowers’ nectar, but not from those in the uncovered flowers’ nectar. We conclude that the honeybees may introduce bacteria into the nectar and/or may be contaminated by bacteria introduced into the nectar by other sources such as other pollinators and nectar thieves. PMID:23844027

  11. Behavior and pollination efficiency of Nannotrigona perilampoides (Hymenoptera: Meliponini) on greenhouse tomatoes (Lycopersicon esculentum) in subtropical México.

    Science.gov (United States)

    Cauich, Orlando; Quezada-Euán, José Javier G; Macias-Macias, José Octavio; Reyes-Oregel, Vicente; Medina-Peralta, Salvador; Parra-Tabla, Victor

    2004-04-01

    The acclimation, foraging behavior, and pollination efficiency of stingless bees of the species Nannotrigona perilampoides Cresson were evaluated in tomato (Lycopersicon esculentum Mill.) plants cultivated in two greenhouses. The greenhouses were divided into three areas of 16 m2, and one of the following treatments was used for pollination: stingless bees (SB), mechanical vibration (MV), and no pollination (NP). Observations were conducted once a week from 0800 to 1600 hours during 2 mo. The acclimation of the bees to the greenhouses was estimated by the number of bees that did not return to the hive (lost bees) and by comparing the population of the colonies (brood and adults). The foraging activity of the bees across the day was evaluated by comparing the number of foragers per hour. The influence of environmental variables on the foraging activity was also analyzed. The pollination efficiency was compared among treatments through the percentage of fruit set, weight of individual fruit, kilograms of fruit produced per square meter, and the number of seed per fruit. The bees started foraging on the flowers approximately 7 d after the colonies were introduced to the greenhouse. There was a decline in the population of the colonies across the experiment, but colonies did not die out. Correlations of environmental variables with the foraging activity of the bees showed that none of them had a significant influence on pollen foraging. However, water collection was positively correlated with the temperature and negatively correlated with the humidity inside the greenhouse. The estimation of the pollination efficiency per treatment showed that there were significant differences in fruit set in SB (83 +/- 4.2) and MV (78.5 +/- 6.4) compared with NP (52.6 +/- 7.6). However, the average weight of the fruit was similar for the three treatments (65 g). There were significant differences for seed number in SB (200 +/- 15.3) and MV (232 +/- 21.4) compared with NP (120 +/- 16

  12. 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.

  13. 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

  14. Chronic neonicotinoid pesticide exposure and parasite stress differentially affects learning in honeybees and bumblebees

    Science.gov (United States)

    2016-01-01

    Learning and memory are crucial functions which enable insect pollinators to efficiently locate and extract floral rewards. Exposure to pesticides or infection by parasites may cause subtle but ecologically important changes in cognitive functions of pollinators. The potential interactive effects of these stressors on learning and memory have not yet been explored. Furthermore, sensitivity to stressors may differ between species, but few studies have compared responses in different species. Here, we show that chronic exposure to field-realistic levels of the neonicotinoid clothianidin impaired olfactory learning acquisition in honeybees, leading to potential impacts on colony fitness, but not in bumblebees. Infection by the microsporidian parasite Nosema ceranae slightly impaired learning in honeybees, but no interactive effects were observed. Nosema did not infect bumblebees (3% infection success). Nevertheless, Nosema-treated bumblebees had a slightly lower rate of learning than controls, but faster learning in combination with neonicotinoid exposure. This highlights the potential for complex interactive effects of stressors on learning. Our results underline that one cannot readily extrapolate findings from one bee species to others. This has important implications for regulatory risk assessments which generally use honeybees as a model for all bees. PMID:27053744

  15. Chronic neonicotinoid pesticide exposure and parasite stress differentially affects learning in honeybees and bumblebees.

    Science.gov (United States)

    Piiroinen, Saija; Goulson, Dave

    2016-04-13

    Learning and memory are crucial functions which enable insect pollinators to efficiently locate and extract floral rewards. Exposure to pesticides or infection by parasites may cause subtle but ecologically important changes in cognitive functions of pollinators. The potential interactive effects of these stressors on learning and memory have not yet been explored. Furthermore, sensitivity to stressors may differ between species, but few studies have compared responses in different species. Here, we show that chronic exposure to field-realistic levels of the neonicotinoid clothianidin impaired olfactory learning acquisition in honeybees, leading to potential impacts on colony fitness, but not in bumblebees. Infection by the microsporidian parasite Nosema ceranae slightly impaired learning in honeybees, but no interactive effects were observed. Nosema did not infect bumblebees (3% infection success). Nevertheless, Nosema-treated bumblebees had a slightly lower rate of learning than controls, but faster learning in combination with neonicotinoid exposure. This highlights the potential for complex interactive effects of stressors on learning. Our results underline that one cannot readily extrapolate findings from one bee species to others. This has important implications for regulatory risk assessments which generally use honeybees as a model for all bees. © 2016 The Author(s).

  16. Pollination efficiency and effectiveness or bumble bees and hummingbirds visiting Delphinium nelsonii

    Directory of Open Access Journals (Sweden)

    Waser, Nicholas M.

    1990-12-01

    Full Text Available Delphinium nelsonii Greene is a spring-flowering perennial of the Rocky Mountains of North America. Its blue flowers conform to a classical «bee pollination syndrome», but in western Colorado they are visited by hummingbirds (mostly in the first half of the flowering season as well as bumble bee queens (mostly in the second half of the season. Experiments with potted plants showed that a bee deposits about 10 times as much pollen while visiting a flower as does a bird, and causes about la times as many seeds to be set. In contrast, bees and birds appear similar in the «quality» of pollen they deliver, e. g., in its outcrossing distance. At the level of entire pollinator populations, hummingbird visitation rates may be over 10 times as great as those or bumble bees, in part because birds visit flowers more quickly. Thus the two visitor classes should deliver similar pollen quantities overall, which is confirmed by similar pollen loads of flowers early and late in the season, and should contribute about equally to seed set, which is confirmed by several experiments and observations. Exact relative contributions probably depend on pollinator population sizes, which in the case of hummingbirds appear to have varied 2.5 fold across 14 years. The similar contributions or birds and bees lo seed set shows that individual pollination efficiency must be distinguished from population-level effectiveness. and that the «pollination syndrome» of a flower may not indicate present-day effectiveness of its visitors.

    [ca] Delphinium nelsonii Greene és una planta perenne de floració primaveral que creix a les Muntanyes Rocoses de Nordamèrica. Les seves flors blaves s'acorden a la clàssica (síndrome de pol-linització per abellots», però, a l'oest de Colorado, són visitades per colibrís (durant la primera meitat del període de floració així com per reines d'abellots (principalment durant la segona meitat del període. Els

  17. Effect of ultraviolet radiation absorbing film on pollination work of foreign bumblebee [Bombus terrestris

    International Nuclear Information System (INIS)

    Nishiguchi, I.

    1999-01-01

    The transmitted light through the ultraviolet radiation absorbing (UVA) film has a preventing effect of disease and pest occurrence. To develop the agriculture harmonized with the ecosystem, we attempted to research a further possible utilization of the UVA film. Pollination work of foreign bumblebee (Bombus terrestris) in the greenhouses roofed with UVA film and with common film for agriculture was examined in growing fruit-vegetables. The bumblebees used were not acclimatized to environmental conditions of the greenhouses. They visited flowers and gathered pollen from flowered crops grown in both houses, irrespective of the kind of film covering over the greenhouse roof, and the pollen quantity gathered was far greater in crops which produced in large quantity of pollen. Thus, the bumblebees were capable to work under the condition lacking in ultraviolet radiation. This pollinating behavior is different from that of honeybees. Then we concluded that bumblebees functioned well as an efficient pollinator under the condition without ultraviolet radiation

  18. Large pollen loads of a South African asclepiad do not interfere with the foraging behaviour or efficiency of pollinating honey bees

    Science.gov (United States)

    Coombs, G.; Dold, A. P.; Brassine, E. I.; Peter, C. I.

    2012-07-01

    The pollen of asclepiads (Asclepiadoideae, Apocynaceae) and most orchids (Orchidaceae) are packaged as large aggregations known as pollinaria that are removed as entire units by pollinators. In some instances, individual pollinators may accumulate large loads of these pollinaria. We found that the primary pollinator of Cynanchum ellipticum (Apocynaceae—Asclepiadoideae), the honey bee Apis mellifera, accumulate very large agglomerations of pollinaria on their mouthparts when foraging on this species. We tested whether large pollinarium loads negatively affected the foraging behaviour and foraging efficiency of honey bees by slowing foraging speeds or causing honey bees to visit fewer flowers, and found no evidence to suggest that large pollinarium loads altered foraging behaviour. C. ellipticum displayed consistently high levels of pollination success and pollen transfer efficiency (PTE). This may be a consequence of efficiently loading large numbers of pollinaria onto pollinators even when primary points of attachment on pollinators are already occupied and doing so in a manner that does not impact the foraging behaviour of pollinating insects.

  19. Morphometry, floral resources and efficiency of natural and artificial pollination in fruit quality in cultivars of sour passion fruit

    Directory of Open Access Journals (Sweden)

    Laís Alves Lage

    2018-05-01

    Full Text Available Abstract This study aimed to provide information on the biology and floral resources, stigmatic receptivity and viability of pollen grains during rainy season and dry season, and to evaluate the efficiency of natural and artificial pollination on quality of fruits of eight passion fruit cultivars sourced in Tangará da Serra - MT. Five commercial cultivars and three populations of the genetic improvement program of the sour passion fruit from the Universidade do Estado de Mato Grosso were evaluated. The climatic conditions of the rainy season favored the greater development of the floral pieces. The sugar concentration in the nectar presented higher averages in the rainy season, in all cultivars, except for FB 200. The climatic conditions of the dry season favored the replacement of the nectar volume. All cultivars evaluated presented pollen viability and stigmatic receptivity higher than 79% and 90%, respectively. The characteristics of fruit mass and percentage of pulp were better in artificial pollination, and the fruits obtained from natural and artificial pollination in all cultivars evaluated presented physical and chemical characteristics that are within the quality standards desired in the commercialization.

  20. Pollination success following loss of a frequent pollinator: the role of compensatory visitation by other effective pollinators

    Science.gov (United States)

    Hallett, Allysa C.; Mitchell, Randall J.; Chamberlain, Evan R.

    2017-01-01

    Abstract Pollinator abundance is declining worldwide and may lower the quantity and quality of pollination services to flowering plant populations. Loss of an important pollinator is often assumed to reduce the amount of pollen received by stigmas of a focal species (pollination success), yet this assumption has rarely been tested experimentally. The magnitude of the effect, if any, may depend on the relative efficiency of the remaining pollinators, and on whether the loss of one pollinator leads to changes in visitation patterns by other pollinators. To explore how a change in pollinator composition influences pollination of Asclepias verticillata, we excluded bumble bees from plots in large and small populations of this milkweed species. We then quantified pollinator visitation rates, pollen export and pollen receipt for control plots and for plots where bumble bees were experimentally excluded. We found that exclusion of bumble bees did not reduce pollen receipt by A. verticillata flowers. Visitation by Polistes wasps increased markedly following bumble bee exclusion, both in small populations (186 % increase) and in large populations (400 % increase). Because Polistes wasps were as efficient as bumble bees at pollen transfer, increased wasp visitation offset lost bumble bee pollination services. Thus, loss of a frequent pollinator will not necessarily lead to a decline in pollination success. When pollinator loss is followed by a shift in the composition and abundance of remaining pollinators, pollination success will depend on the net change in the quantity and quality of pollination services. PMID:28798863

  1. 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.

  2. 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.

  3. 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

  4. Pollination crisis in the butterfly-pollinated wild carnation Dianthus carthusianorum?

    Science.gov (United States)

    Bloch, Daniel; Werdenberg, Niels; Erhardt, Andreas

    2006-01-01

    Knowledge of pollination services provided by flower visitors is a prerequisite for understanding (co)evolutionary processes between plants and their pollinators, for evaluating the degree of specialization in the pollination system, and for assessing threats from a potential pollination crisis. This study examined pollination efficiency and visitation frequency of pollinators--key traits of pollinator-mediated fecundity--in a natural population of the wild carnation Dianthus carthusianorum. The five lepidopteran pollinator species observed differed in pollination efficiency and visitation frequency. Pollinator importance, the product of pollination efficiency and visitation frequency, was determined by the pollinator's visitation frequency. Pollination of D. carthusianorum depended essentially on only two of the five recorded pollinator species. Seed set was pollen-limited and followed a saturating dose-response function with a threshold of c. 50 deposited pollen grains for fruit development. Our results confirm that D. carthusianorum is specialized to lepidopteran pollinators, but is not particularly adapted to the two main pollinator species identified. The local persistence of D. carthusianorum is likely to be at risk as its reproduction depends essentially on only two of the locally abundant, but generally vulnerable, butterfly species.

  5. 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.

  6. Aspects of the use of honeybees and bumblebees as vector of antagonistic micro-organisms in plant diseas control

    NARCIS (Netherlands)

    Steen, van der J.J.M.; Langerak, C.J.; Tongeren, van C.A.M.; Dik, A.J.

    2003-01-01

    Honeybees (Apis mellifera L.) and bumblebees (Bombus terrestris L.) are used for pollination in agriculture and horticulture. The morphological and behavioural characteristics of bees make them good pollinators. Thanks to this, bees may also be used as vector of antagonistic micro-organisms for

  7. Distinguishing feral and managed honeybees (Apis mellifera) using stable carbon isotopes

    OpenAIRE

    Anderson , Lucy; Dynes , Travis; Berry , Jennifer; Delaplane , Keith; McCormick , Lydia; Brosi , Berry

    2014-01-01

    International audience; The ability to distinguish feral and managed honeybees (Apis mellifera) has applications in studies of population genetics, parasite transmission, pollination, interspecific interactions, and bee breeding. We evaluated a diagnostic test based on theoretical differences in stable carbon isotope ratios generated by supplemental feeding. We evaluated (1) if carbon isotope ratios can distinguish feral and managed honeybees and (2) the temporal persistence of the signal aft...

  8. 19 CFR 12.32 - Honeybees and honeybee semen.

    Science.gov (United States)

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Honeybees and honeybee semen. 12.32 Section 12.32... semen. (a) Honeybees from any country may be imported into the U.S. by the Department of Agriculture for.... (b) Honeybee semen may be imported into the U.S. only from countries determined by the Secretary of...

  9. 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.

  10. Sensitivity of commercial pumpkin yield to potential decline among different groups of pollinating bees

    Science.gov (United States)

    Eckerter, Philipp W.; Schirmel, Jens; Cresswell, James E.; Entling, Martin H.

    2017-01-01

    The yield of animal-pollinated crops is threatened by bee declines, but its precise sensitivity is poorly known. We therefore determined the yield dependence of Hokkaido pumpkin in Germany on insect pollination by quantifying: (i) the relationship between pollen receipt and fruit set and (ii) the cumulative pollen deposition of each pollinator group. We found that approximately 2500 pollen grains per flower were needed to maximize fruit set. At the measured rates of flower visitation, we estimated that bumblebees (21 visits/flower lifetime, 864 grains/visit) or honeybees (123 visits, 260 grains) could individually achieve maximum crop yield, whereas halictid bees are ineffective (11 visits, 16 grains). The pollinator fauna was capable of delivering 20 times the necessary amount of pollen. We therefore estimate that pumpkin yield was not pollination-limited in our study region and that it is currently fairly resilient to single declines of honeybees or wild bumblebees. PMID:28573019

  11. Sensitivity of commercial pumpkin yield to potential decline among different groups of pollinating bees.

    Science.gov (United States)

    Pfister, Sonja C; Eckerter, Philipp W; Schirmel, Jens; Cresswell, James E; Entling, Martin H

    2017-05-01

    The yield of animal-pollinated crops is threatened by bee declines, but its precise sensitivity is poorly known. We therefore determined the yield dependence of Hokkaido pumpkin in Germany on insect pollination by quantifying: (i) the relationship between pollen receipt and fruit set and (ii) the cumulative pollen deposition of each pollinator group. We found that approximately 2500 pollen grains per flower were needed to maximize fruit set. At the measured rates of flower visitation, we estimated that bumblebees (21 visits/flower lifetime, 864 grains/visit) or honeybees (123 visits, 260 grains) could individually achieve maximum crop yield, whereas halictid bees are ineffective (11 visits, 16 grains). The pollinator fauna was capable of delivering 20 times the necessary amount of pollen. We therefore estimate that pumpkin yield was not pollination-limited in our study region and that it is currently fairly resilient to single declines of honeybees or wild bumblebees.

  12. Parameterization of the InVEST Crop Pollination Model to spatially predict abundance of wild blueberry (Vaccinium angustifolium Aiton) native bee pollinators in Maine, USA

    Science.gov (United States)

    Groff, Shannon C.; Loftin, Cynthia S.; Drummond, Frank; Bushmann, Sara; McGill, Brian J.

    2016-01-01

    Non-native honeybees historically have been managed for crop pollination, however, recent population declines draw attention to pollination services provided by native bees. We applied the InVEST Crop Pollination model, developed to predict native bee abundance from habitat resources, in Maine's wild blueberry crop landscape. We evaluated model performance with parameters informed by four approaches: 1) expert opinion; 2) sensitivity analysis; 3) sensitivity analysis informed model optimization; and, 4) simulated annealing (uninformed) model optimization. Uninformed optimization improved model performance by 29% compared to expert opinion-informed model, while sensitivity-analysis informed optimization improved model performance by 54%. This suggests that expert opinion may not result in the best parameter values for the InVEST model. The proportion of deciduous/mixed forest within 2000 m of a blueberry field also reliably predicted native bee abundance in blueberry fields, however, the InVEST model provides an efficient tool to estimate bee abundance beyond the field perimeter.

  13. Evaluation of Yield Component Traits of Honeybee-Pollinated (Apis mellifera L.Rapeseed Canola (Brassica napus L. Evaluación de Parámetros de Rendimiento del Raps (Brassica napus L. Polinizado por Abejas (Apis mellifera L.

    Directory of Open Access Journals (Sweden)

    Ximena Araneda Durán

    2010-06-01

    Full Text Available Recent introduction of hybrid varieties raises the question if bees (Apis mellifera L. contribute as pollinator agents in developing the full yield potential of rapeseed (Brassica napus L.. In order to evaluate the yield achieved by B. napus cv. Artus pollinated by A. mellifera testing was carried out in the district of Freire, La Araucanía Region, Chile. This consisted in isolating or excluding rapeseed plants from pollinators with exclusion cages. Treatments applied were total exclusion (T1, partial exclusion (T2 and free pollination (T0 with a density of 6.5 hives ha-1, in order to determine the following yield components traits: grains per silique, siliques per plant, 1000 grain weight and yield. The experimental design used was randomized complete blocks with three treatments and three replicates. Results obtained show that the parameter least affected by bee intervention was the grains per silique variable. In contrast, siliques per plant and 1000 grain weight parameters presented significant differences, contributing to a yield greater than 5 t ha-1; which represented a figure 50.34% higher than in the treatment without bees. It may be concluded that the inclusion of bees in crops is fully justified as a production tool.La reciente introducción de variedades híbridas plantea la interrogante de la contribución que pueda tener la presencia de abejas (Apis mellifera L. como agentes polinizadores para desarrollar en pleno el potencial productivo del raps (Brassica napus L.. Con el objetivo de evaluar el rendimiento alcanzado por B. napus cv. Artus polinizado por A. mellifera, se realizó un ensayo en la localidad de Freire, Región de La Araucanía, Chile. Éste consistió en aislar o excluir las plantas de raps de los polinizadores mediante el uso de jaulas excluidoras. Los tratamientos consistieron en la exclusión total (T1, exclusión parcial (T2 y libre polinización (T0 con una densidad de 6,5 colmenas ha-1, con el fin de determinar

  14. Experimental evidence that honeybees depress wild insect densities in a flowering crop.

    Science.gov (United States)

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

    2016-11-30

    While addition of managed honeybees (Apis mellifera) improves pollination of many entomophilous crops, it is unknown if it simultaneously suppresses the densities of wild insects through competition. To investigate this, we added 624 honeybee hives to 23 fields of oilseed rape (Brassica napus L.) over 2 years and made sure that the areas around 21 other fields were free from honeybee hives. We demonstrate that honeybee addition depresses the densities of wild insects (bumblebees, solitary bees, hoverflies, marchflies, other flies, and other flying and flower-visiting insects) even in a massive flower resource such as oilseed rape. The effect was independent of the complexity of the surrounding landscape, but increased with the size of the crop field, which suggests that the effect was caused by spatial displacement of wild insects. Our results have potential implications both for the pollination of crops (if displacement of wild pollinators offsets benefits achieved by adding honeybees) and for conservation of wild insects (if displacement results in negative fitness consequences). © 2016 The Author(s).

  15. Interaction between Varroa destructor and imidacloprid reduces flight capacity of honeybees

    NARCIS (Netherlands)

    Blanken, Lisa; Langevelde, van F.; Dooremalen, van J.A.

    2015-01-01

    Current high losses of honeybees seriously threaten crop pollination. Whereas parasite exposure is acknowledged as an important cause of these losses, the role of insecticides is controversial. Parasites and neonicotinoid insecticides reduce homing success of foragers (e.g. by reduced orientation),

  16. The virulent, emerging genotype B of Deformed wing virus is closely linked to overwinter honeybee worker loss

    DEFF Research Database (Denmark)

    Natsopoulou, Myrsini Eirini; McMahon, Dino P.; Doublet, Vincent

    2017-01-01

    Bees are considered to be threatened globally, with severe overwinter losses of the most important commercial pollinator, the Western honeybee, a major concern in the Northern Hemisphere. Emerging infectious diseases have risen to prominence due to their temporal correlation with colony losses...... of elevated overwinter honeybee loss. Its potential emergence in naïve populations of bees may have far-reaching ecological and economic impacts....

  17. A Locomotor Deficit Induced by Sublethal Doses of Pyrethroid and Neonicotinoid Insecticides in the Honeybee Apis mellifera

    OpenAIRE

    Charreton, Merc?d?s; Decourtye, Axel; Henry, Micka?l; Rodet, Guy; Sandoz, Jean-Christophe; Charnet, Pierre; Collet, Claude

    2015-01-01

    The toxicity of pesticides used in agriculture towards non-targeted organisms and especially pollinators has recently drawn the attention from a broad scientific community. Increased honeybee mortality observed worldwide certainly contributes to this interest. The potential role of several neurotoxic insecticides in triggering or potentiating honeybee mortality was considered, in particular phenylpyrazoles and neonicotinoids, given that they are widely used and highly toxic for insects. Along...

  18. Interactive effects of large- and small-scale sources of feral honey-bees for sunflower in the Argentine Pampas.

    Directory of Open Access Journals (Sweden)

    Agustín Sáez

    Full Text Available Pollinators for animal pollinated crops can be provided by natural and semi-natural habitats, ranging from large vegetation remnants to small areas of non-crop land in an otherwise highly modified landscape. It is unknown, however, how different small- and large-scale habitat patches interact as pollinator sources. In the intensively managed Argentine Pampas, we studied the additive and interactive effects of large expanses (up to 2200 ha of natural habitat, represented by untilled isolated "sierras", and narrow (3-7 m wide strips of semi-natural habitat, represented by field margins, as pollinator sources for sunflower (Helianthus annus. We estimated visitation rates by feral honey-bees, Apis mellifera, and native flower visitors (as a group at 1, 5, 25, 50 and 100 m from a field margin in 17 sunflower fields 0-10 km distant from the nearest sierra. Honey-bees dominated the pollinator assemblage accounting for >90% of all visits to sunflower inflorescences. Honey-bee visitation was strongly affected by proximity to the sierras decreasing by about 70% in the most isolated fields. There was also a decline in honey-bee visitation with distance from the field margin, which was apparent with increasing field isolation, but undetected in fields nearby large expanses of natural habitat. The probability of observing a native visitor decreased with isolation from the sierras, but in other respects visitation by flower visitors other than honey-bees was mostly unaffected by the habitat factors assessed in this study. Overall, we found strong hierarchical and interactive effects between the study large and small-scale pollinator sources. These results emphasize the importance of preserving natural habitats and managing actively field verges in the absence of large remnants of natural habitat for improving pollinator services.

  19. Interactive effects of large- and small-scale sources of feral honey-bees for sunflower in the Argentine Pampas.

    Science.gov (United States)

    Sáez, Agustín; Sabatino, Malena; Aizen, Marcelo A

    2012-01-01

    Pollinators for animal pollinated crops can be provided by natural and semi-natural habitats, ranging from large vegetation remnants to small areas of non-crop land in an otherwise highly modified landscape. It is unknown, however, how different small- and large-scale habitat patches interact as pollinator sources. In the intensively managed Argentine Pampas, we studied the additive and interactive effects of large expanses (up to 2200 ha) of natural habitat, represented by untilled isolated "sierras", and narrow (3-7 m wide) strips of semi-natural habitat, represented by field margins, as pollinator sources for sunflower (Helianthus annus). We estimated visitation rates by feral honey-bees, Apis mellifera, and native flower visitors (as a group) at 1, 5, 25, 50 and 100 m from a field margin in 17 sunflower fields 0-10 km distant from the nearest sierra. Honey-bees dominated the pollinator assemblage accounting for >90% of all visits to sunflower inflorescences. Honey-bee visitation was strongly affected by proximity to the sierras decreasing by about 70% in the most isolated fields. There was also a decline in honey-bee visitation with distance from the field margin, which was apparent with increasing field isolation, but undetected in fields nearby large expanses of natural habitat. The probability of observing a native visitor decreased with isolation from the sierras, but in other respects visitation by flower visitors other than honey-bees was mostly unaffected by the habitat factors assessed in this study. Overall, we found strong hierarchical and interactive effects between the study large and small-scale pollinator sources. These results emphasize the importance of preserving natural habitats and managing actively field verges in the absence of large remnants of natural habitat for improving pollinator services.

  20. 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.

  1. Towards a systems approach for understanding honeybee decline: a stocktaking and synthesis of existing models.

    Science.gov (United States)

    Becher, Matthias A; Osborne, Juliet L; Thorbek, Pernille; Kennedy, Peter J; Grimm, Volker

    2013-08-01

    The health of managed and wild honeybee colonies appears to have declined substantially in Europe and the United States over the last decade. Sustainability of honeybee colonies is important not only for honey production, but also for pollination of crops and wild plants alongside other insect pollinators. A combination of causal factors, including parasites, pathogens, land use changes and pesticide usage, are cited as responsible for the increased colony mortality.However, despite detailed knowledge of the behaviour of honeybees and their colonies, there are no suitable tools to explore the resilience mechanisms of this complex system under stress. Empirically testing all combinations of stressors in a systematic fashion is not feasible. We therefore suggest a cross-level systems approach, based on mechanistic modelling, to investigate the impacts of (and interactions between) colony and land management.We review existing honeybee models that are relevant to examining the effects of different stressors on colony growth and survival. Most of these models describe honeybee colony dynamics, foraging behaviour or honeybee - varroa mite - virus interactions.We found that many, but not all, processes within honeybee colonies, epidemiology and foraging are well understood and described in the models, but there is no model that couples in-hive dynamics and pathology with foraging dynamics in realistic landscapes. Synthesis and applications . We describe how a new integrated model could be built to simulate multifactorial impacts on the honeybee colony system, using building blocks from the reviewed models. The development of such a tool would not only highlight empirical research priorities but also provide an important forecasting tool for policy makers and beekeepers, and we list examples of relevant applications to bee disease and landscape management decisions.

  2. Modelling Gene Flow between Fields of White Clover with Honeybees as Pollen Vectors

    DEFF Research Database (Denmark)

    Løjtnant, Christina; Boelt, Birte; Clausen, Sabine Karin

    2012-01-01

    The portion-dilution model is a parametric restatement of the conventional view of animal pollination; it predicts the level of pollinator-mediated gene dispersal. In this study, the model was applied to white clover (Trifolium repens) and its most frequent pollinator, the honeybee (Apis mellifera......). One of the three parameters in the portion-dilution model is the mean number of flowers a pollinator visits in one foraging bout. An alternative method to estimate this parameter was developed that was not depending on pollinator hive-seeking behaviour. The new estimation method, based on nectar......% with an estimated 95% percentile of 70%. The results show that the European Union threshold limit of 0.9% GM admixture for food and feed will likely be exceeded at times and especially organic farmers that do not accept GM admixture and often have clover and clover–grass fields might face challenges with admixture...

  3. 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.

  4. Variations in pollinator density and impacts on large cardamom (Amomum subulatum Roxb. crop yield in Sikkim Himalaya, India

    Directory of Open Access Journals (Sweden)

    Kailash S. Gaira

    2016-03-01

    Full Text Available Large cardamom (Amomum subulatum Roxb., a perennial cash crop, cultivated under an agroforestry system in the eastern Himalaya of India, is well recognized as a pollination-dependent crop. Observations on pollinator abundance in Mamlay watershed of Sikkim Himalaya were collected during the blooming season to evaluate the pollinator abundance across sites and time frames, and impact of pollinator abundance on crop yield from 2010 to 2012. The results revealed that the bumblebees and honeybees are most frequent visitors of large cardamom flowers. The abundance of honeybees, however, varied between sites for the years 2010–2012, while that of bumblebees varied for the years 2011 and 2012. The abundance of honeybees resulted in a variation within time frames for 2010 and 2011, while that of bumblebees varied for 2010 and 2012 (p<0.01. The density of pollinators correlated positively with the number of flowers of the target crop. The impact of pollinator abundance revealed that the increasing bumblebee visitation resulted in a higher yield of the crop (i.e. 17–41 g/plant and the increasing abundance of all bees (21–41 g/plant was significant (p<0.03. Therefore, the study concluded that the large cardamom yield is sensitive to pollinator abundance and there is a need for adopting the best pollinator conservation and management practices toward sustaining the yield of large cardamom.

  5. Honeybees Increase Fruit Set in Native Plant Species Important for Wildlife Conservation

    Science.gov (United States)

    Cayuela, Luis; Ruiz-Arriaga, Sarah; Ozers, Christian P.

    2011-11-01

    Honeybee colonies are declining in some parts of the world. This may have important consequences for the pollination of crops and native plant species. In Spain, as in other parts of Europe, land abandonment has led to a decrease in the number of non professional beekeepers, which aggravates the problem of honeybee decline as a result of bee diseases In this study, we investigated the effects of honeybees on the pollination of three native plant species in northern Spain, namely wildcherry Prunus avium L., hawthorn Crataegus monogyna Jacq., and bilberry Vaccinium myrtillus L. We quantified fruit set of individuals from the target species along transects established from an apiary outwards. Half the samples were bagged in a nylon mesh to avoid insect pollination. Mixed-effects models were used to test the effect of distance to the apiary on fruit set in non-bagged samples. The results showed a negative significant effect of distance from the apiary on fruit set for hawthorn and bilberry, but no significant effects were detected for wildcherry. This suggests that the use of honeybees under traditional farming practices might be a good instrument to increase fruit production of some native plants. This may have important consequences for wildlife conservation, since fruits, and bilberries in particular, constitute an important feeding resource for endangered species, such as the brown bear Ursus arctos L. or the capercaillie Tetrao urogallus cantabricus L.

  6. The relative contribution of diurnal and nocturnal pollinators to plant female fitness in a specialized nursery pollination system.

    Science.gov (United States)

    Scopece, Giovanni; Campese, Lucia; Duffy, Karl J; Cozzolino, Salvatore

    2018-02-01

    Plants involved in specialized pollinator interactions, such as nursery pollination, may experience trade-offs in their female fitness, as the larvae of their pollinators may also consume seeds produced by the flowers they pollinate. These interactions could potentially shift between mutualism and parasitism, depending on the presence and abundance of both the nursery pollinator and of other pollinators. We investigated the fitness trade-off in a Mediterranean plant ( Silene latifolia ), which has a specialist nocturnal nursery pollinator moth ( Hadena bicruris ) and is also visited by several diurnal pollinators. We estimated the pollination rates and fecundity of S. latifolia in both natural and experimental populations in the Mediterranean. We estimated natural pollination rates in different flowering times and with presence/absence of the H. bicruis moth. Then by exposing plants to each pollinator group either during the day or at night, we quantified the contribution of other diurnal pollinators and the specialized nocturnal nursery pollinator to plant female fitness. We found no difference in plant fruit set mediated by diurnal versus nocturnal pollinators, indicating that non-specialist pollinators contribute to plant female fitness. However, in both natural and experimental populations, H. bicruris was the most efficient pollinator in terms of seeds produced per fruit. These results suggest that the female fitness costs generated by nursery pollination can be overcome through higher fertilization rates relative to predation rates, even in the presence of co-pollinators. Quantifying such interactions is important for our understanding of the selective pressures that promote highly specialized mutualisms, such as nursery pollination, in the Mediterranean region, a centre of diversification of the carnation family.

  7. 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

  8. Contribution of insect pollinators to crop yield and quality varies with agricultural intensification.

    Science.gov (United States)

    Bartomeus, Ignasi; Potts, Simon G; Steffan-Dewenter, Ingolf; Vaissière, Bernard E; Woyciechowski, Michal; Krewenka, Kristin M; Tscheulin, Thomas; Roberts, Stuart P M; Szentgyörgyi, Hajnalka; Westphal, Catrin; Bommarco, Riccardo

    2014-01-01

    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 pollinators in

  9. Vultures and honeybees

    African Journals Online (AJOL)

    ZeldaH

    in the Ganab area of the Namib-Naukluft. Park, Namibia, we came across an unusual occurrence: When we reached the chick in the nest, we found honeybees Apis mellifera, crowded over and covering the eyes of the young vulture. The Namib-Naukluft Park (NNP),. 49,785 km², is the largest conservation area in Namibia ...

  10. Pollinator specialization and pollination syndromes of three related North American Silene.

    Science.gov (United States)

    Reynolds, Richard J; Westbrook, M Jody; Rohde, Alexandra S; Cridland, Julie M; Fenster, Charles B; Dudash, Michele R

    2009-08-01

    Community and biogeographic surveys often conclude that plant-pollinator interactions are highly generalized. Thus, a central implication of the pollination syndrome concept, that floral trait evolution occurs primarily via specialized interactions of plants with their pollinators, has been questioned. However, broad surveys may not distinguish whether flower visitors are actual pollen vectors and hence lack power to assess the relationship between syndrome traits and the pollinators responsible for their evolution. Here we address whether the floral traits of three closely related hermaphroditic Silene spp. native to eastern North America (S. caroliniana, S. virginica, and S. stellata) correspond to predicted specialized pollination based on floral differences among the three species and the congruence of these floral features with recognized pollination syndromes. A nocturnal/diurnal pollinator exclusion experiment demonstrated that all three Silene spp. have diurnal pollinators, and only S. stellata has nocturnal pollinators. Multiyear studies of visitation rates demonstrated that large bees, hummingbirds, and nocturnal moths were the most frequent pollinators of S. caroliniana, S. virginica, and S. stellata, respectively. Estimates of pollen grains deposited and removed per visit generally corroborated the visitation rate results for all three species. However, the relatively infrequent diurnal hawkmoth pollinators of S. caroliniana were equally effective and more efficient than the most frequent large bee visitors. Pollinator importance (visitation X deposition) of each of the animal visitors to each species was estimated and demonstrated that in most years large bees and nocturnal moths were the most important pollinators of S. caroliniana and S. stellata, respectively. By quantifying comprehensive aspects of the pollination process we determined that S. virginica and S. stellata were specialized on hummingbirds and nocturnal moths, respectively, and S

  11. Controlled mass pollination in loblolly pine to increase genetic gains

    Science.gov (United States)

    F.E. Bridgwater; D.L. Bramlett; T.D. Byram; W.J. Lowe

    1998-01-01

    Controlled mass pollination (CMP) is one way to increase genetic gains from traditional wind-pollinated seed orchards. Methodology is under development by several forestry companies in the southern USA. Costs of CMP depend on the efficient installation, pollination, and removal of inexpensive paper bags. Even in pilot-scale studies these costs seem reasonable. Net...

  12. How to Sustainably Increase Students' Willingness to Protect Pollinators

    Science.gov (United States)

    Schönfelder, Mona L.; Bogner, Franz X.

    2018-01-01

    The current loss of biodiversity requires efforts to increase awareness of pollinator conservation. An important tool is education which often uses the honeybee ("Apis mellifera") as an exemplary organism to reach this goal. Any successful module needs to focus on reducing the perceived danger associated with fear, in order to support…

  13. Pollinator diversity (Hymenoptera and Diptera in semi-natural habitats in Serbia during summer

    Directory of Open Access Journals (Sweden)

    Mudri-Stojnić Sonja

    2012-01-01

    Full Text Available The aim of this study was to assess species diversity and population abundance of the two main orders of pollinating insects, Hymenoptera and Diptera. The survey was conducted in 16 grassland fragments within agro-ecosystems in Vojvodina, as well as in surrounding fields with mass-flowering crops. Pollinators were identified and the Shannon-Wiener Diversity Index was used to measure their diversity. Five families, 7 subfamilies, 26 genera and 63 species of insects were recorded. All four big pollinator groups investigated were recorded; hoverflies were the most abundant with 32% of the total number of individuals, followed by wild bees - 29%, honeybees - 23% and bumblebees with 16%.

  14. Orchid pollination by sexual deception: pollinator perspectives.

    Science.gov (United States)

    Gaskett, A C

    2011-02-01

    The extraordinary taxonomic and morphological diversity of orchids is accompanied by a remarkable range of pollinators and pollination systems. Sexually deceptive orchids are adapted to attract specific male insects that are fooled into attempting to mate with orchid flowers and inadvertently acting as pollinators. This review summarises current knowledge, explores new hypotheses in the literature, and introduces some new approaches to understanding sexual deception from the perspective of the duped pollinator. Four main topics are addressed: (1) global patterns in sexual deception, (2) pollinator identities, mating systems and behaviours, (3) pollinator perception of orchid deceptive signals, and (4) the evolutionary implications of pollinator responses to orchid deception, including potential costs imposed on pollinators by orchids. A global list of known and putative sexually deceptive orchids and their pollinators is provided and methods for incorporating pollinator perspectives into sexual deception research are provided and reviewed. At present, almost all known sexually deceptive orchid taxa are from Australia or Europe. A few sexually deceptive species and genera are reported for New Zealand and South Africa. In Central and Southern America, Asia, and the Pacific many more species are likely to be identified in the future. Despite the great diversity of sexually deceptive orchid genera in Australia, pollination rates reported in the literature are similar between Australian and European species. The typical pollinator of a sexually deceptive orchid is a male insect of a species that is polygynous, monandrous, haplodiploid, and solitary rather than social. Insect behaviours involved in the pollination of sexually deceptive orchids include pre-copulatory gripping of flowers, brief entrapment, mating, and very rarely, ejaculation. Pollinator behaviour varies within and among pollinator species. Deception involving orchid mimicry of insect scent signals is

  15. Conserving genetic diversity in the honeybee: comments on Harpur et al. (2012).

    Science.gov (United States)

    De la Rúa, Pilar; Jaffé, Rodolfo; Muñoz, Irene; Serrano, José; Moritz, Robin F A; Kraus, F Bernhard

    2013-06-01

    The article by Harpur et al. (2012) 'Management increases genetic diversity of honey bees via admixture' concludes that '…honey bees do not suffer from reduced genetic diversity caused by management and, consequently, that reduced genetic diversity is probably not contributing to declines of managed Apis mellifera populations'. In the light of current honeybee and beekeeping declines and their consequences for honeybee conservation and the pollination services they provide, we would like to express our concern about the conclusions drawn from the results of Harpur et al. (2012). While many honeybee management practices do not imply admixture, we are convinced that the large-scale genetic homogenization of admixed populations could drive the loss of valuable local adaptations. We also point out that the authors did not account for the extensive gene flow that occurs between managed and wild/feral honeybee populations and raise concerns about the data set used. Finally, we caution against underestimating the importance of genetic diversity for honeybee colonies and highlight the importance of promoting the use of endemic honeybee subspecies in apiculture. © 2013 John Wiley & Sons Ltd.

  16. Assessing pollinators’ use of floral resource subsidies in agri-environment schemes: An illustration using Phacelia tanacetifolia and honeybees

    Directory of Open Access Journals (Sweden)

    Rowan Sprague

    2016-11-01

    Full Text Available Background Honeybees (Apis mellifera L. are frequently used in agriculture for pollination services because of their abundance, generalist floral preferences, ease of management and hive transport. However, their populations are declining in many countries. Agri-Environment Schemes (AES are being implemented in agricultural systems to combat the decline in populations of pollinators and other insects. Despite AES being increasingly embedded in policy and budgets, scientific assessments of many of these schemes still are lacking, and only a few studies have examined the extent to which insect pollinators use the floral enhancements that are part of AES and on which floral components they feed (i.e., pollen and/or nectar. Methods In the present work, we used a combination of observations on honeybee foraging for nectar/pollen from the Californian annual plant Phacelia tanacetifolia in the field, collection of pollen pellets from hives, and pollen identification, to assess the value of adding phacelia to an agro-ecosystem to benefit honeybees. Results It was found that phacelia pollen was almost never taken by honeybees. The work here demonstrates that honeybees may not use the floral enhancements added to a landscape as expected and points to the need for more careful assessments of what resources are used by honeybees in AES and understanding the role, if any, which AES play in enhancing pollinator fitness. Discussion We recommend using the methodology in this paper to explore the efficacy of AES before particular flowering species are adopted more widely to give a more complete illustration of the actual efficacy of AES.

  17. Pollination efficiency of Apis mellifera Linnaeus, 1758 (Hymenoptera, Apidae on the monoecious plants Jatropha mollissima (Pohl Baill. and Jatropha mutabilis (Pohl Baill. (Euphorbiaceae in a semi-arid Caatinga area, northeastern Brazil Eficiência de Apis mellifera Linnaeus, 1758 (Hymenoptera: Apidae na polinização das espécies monoicas Jatropha mollissima (Pohl Baill. e Jatropha mutabilis (Pohl Baill. (Euphorbiaceae em uma área de Caatinga, nordeste do Brasil

    Directory of Open Access Journals (Sweden)

    EL. Neves

    2011-02-01

    Full Text Available Previous studies have shown the superior competitive ability of honeybees compared with native bees in the exploitation of floral resources and nesting sites besides their low efficiency in pollinating native plant species. However, there is little evidence of the effect of this invading species on autochthonous plant populations in natural environments. Thus experiments were performed to test the pollination efficiency of honeybees in two species of Jatropha (Euphorbiaceae, J. mollissima (Pohl Baill. and J. mutabilis (Pohl Baill., after a single flower visitation. Samplings were carried out between March and April 2006 in a hyperxerophilous shrub-arboreal Caatinga at Estação Biológica de Canudos, Bahia (9º 56´ 34" S, 38º 59´ 17" W, the property of Fundação Biodiversitas. Apis mellifera was efficient at pollinating J. mollissima (100% and J. mutabilis (85%. This high efficiency may be explained by 1 the simple floral characteristics of both plant species, which facilitate access to the sexual organs of the plant; and 2 the body size of A. mellifera that fits the flower's dimensions.Estudos sugerem que Apis mellifera é altamente generalista e oportunista, interfere nas populações de abelhas nativas através da competição por recursos florais e por sítios de nidificação, além de ser pouco eficiente na polinização de espécies nativas. Entretanto, há poucas evidências que comprovem o efeito de Apis mellifera sobre populações autóctones em ambientes naturais. O presente estudo testou experimentalmente a eficiência de A. mellifera na polinização das espécies Jatropha mollissima e J. mutabilis em apenas uma visita e observou o seu comportamento de visitação. As amostragens foram feitas entre março e abril de 2006 em uma área de caatinga hiperxerófila arbustiva-arbórea na Estação Biológica de Canudos, Bahia (9º56´34"S, 38º59´17"W, pertencente à Fundação Biodiversitas. Apis mellifera foi eficiente na poliniza

  18. THE HONEYBEE ACROSS THE CURRICULUM

    African Journals Online (AJOL)

    completed by pupils, followed by questions relating to the anatomy of the honeybee. Chapter Four: The Honeybee at Home. After the swarm1ng, the bu1ld1ng of the nest, the establish- ment of a new community and the mating of the queen and drones, we observe the development of the queen, drone and worker from egg ...

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

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    María Belén Maldonado

    Full Text Available Previous studies have examined separately how pollinator generalization and abundance influence plant reproductive success, but none so far has evaluated simultaneously the relative importance of these pollinator attributes. Here we evaluated the extent to which pollinator generalization and abundance influence plant reproductive success per visit and at the population level on a generalist plant, Opuntia sulphurea (Cactaceae. We used field experiments and path analysis to evaluate whether the per-visit effect is determined by the pollinator's degree of generalization, and whether the population level effect (pollinator impact is determined by the pollinator's degree of generalization and abundance. Based on the models we tested, we concluded that the per-visit effect of a pollinator on plant reproduction was not determined by the pollinators' degree of generalization, while the population-level impact of a pollinator on plant reproduction was mainly determined by the pollinators' degree of generalization. Thus, generalist pollinators have the greatest species impact on pollination and reproductive success of O. sulphurea. According to our analysis this greatest impact of generalist pollinators may be partly explained by pollinator abundance. However, as abundance does not suffice as an explanation of pollinator impact, we suggest that vagility, need for resource consumption, and energetic efficiency of generalist pollinators may also contribute to determine a pollinator's impact on plant reproduction.

  20. The Acute Oral Toxicity of Commonly Used Pesticides in Iran, to Honeybees (Apis Mellifera Meda

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    Rasuli Farhang

    2015-06-01

    Full Text Available The honey bee is credited with approximately 85% of the pollinating activity necessary to supply about one-third of the world’s food supply. Well over 50 major crops depend on these insects for pollination. The crops produce more abundantly when honey bees are plentiful. Worker bees are the ones primarily affected by pesticides. Poisoning symptoms can vary depending on the developmental stage of the individual bee, and the kind of chemical employed. The oral toxicity of these insecticides: (phosalone and pirimicarb, acaricide (propargite, insecticide and acaricide (fenpropathrin, fungicides, and bactericides (copper oxychloride and the Bordeaux mixture, were evaluated for the purposes of this research. The results showed that fenpropathrin had high acute oral toxicity (LC50-24h and LC50-48 were 0.54 and 0.3 ppm, respectively. Propargite had 7785 ppm (active ingredient for LC50-24h and 6736 ppm (active ingredient for LC50-48h in honeybees and is therefore, non-toxic to Apis mellifera. On the other hand, copper oxychloride had minimum acute oral toxicity to honeybees (LC50-24h and LC50-48 were 4591.5 and 5407.9 ppm, respectively and was therefore considered non-toxic. Also, the Bordeaux mixture was safe to use around honeybees. Phosalone and primicarb were considered highly and moderately toxic to honeybees, respectively.

  1. THE HONEYBEE ACROSS THE CURRICULUM

    African Journals Online (AJOL)

    This paper describes a teacher aid progra11111e on the honeybee, which is considered ... environment, and to create job opportunities. • generate a ... skill in architectural design and home building ... three interlinking, yet separate, units: 1.

  2. Plant-pollinator interactions in tropical monsoon forests in Southeast Asia.

    Science.gov (United States)

    Kato, Makoto; Kosaka, Yasuyuki; Kawakita, Atsushi; Okuyama, Yudai; Kobayashi, Chisato; Phimminith, Thavy; Thongphan, Daovorn

    2008-11-01

    Forests with different flora and vegetation types harbor different assemblages of flower visitors, and plant-pollinator interactions vary among forests. In monsoon-dominated East and Southeast Asia, there is a characteristic gradient in climate along latitude, creating a broad spectrum of forest types with potentially diverse pollinator communities. To detect a geographical pattern of plant-pollinator interactions, we investigated flowering phenology and pollinator assemblages in the least-studied forest type, i.e., tropical monsoon forest, in the Vientiane plain in Laos. Throughout the 5-year study, we observed 171 plant species blooming and detected flower visitors on 145 species. Flowering occurred throughout the year, although the number of flowering plant species peaked at the end of dry season. The dominant canopy trees, including Dipterocarpaceae, bloomed annually, in contrast to the supra-annual general flowering that occurs in Southeast Asian tropical rain forests. Among the 134 native plant species, 68 were pollinated by hymenopterans and others by lepidopterans, beetles, flies, or diverse insects. Among the observed bees, Xylocopa, megachilids, and honeybees mainly contributed to the pollination of canopy trees, whereas long-tongued Amegilla bees pollinated diverse perennials with long corolla tubes. This is the first community-level study of plant-pollinator interactions in an Asian tropical monsoon forest ecosystem.

  3. Bee pollination increases yield quantity and quality of cash crops in Burkina Faso, West Africa.

    Science.gov (United States)

    Stein, Katharina; Coulibaly, Drissa; Stenchly, Kathrin; Goetze, Dethardt; Porembski, Stefan; Lindner, André; Konaté, Souleymane; Linsenmair, Eduard K

    2017-12-18

    Mutualistic biotic interactions as among flowering plants and their animal pollinators are a key component of biodiversity. Pollination, especially by insects, is a key element in ecosystem functioning, and hence constitutes an ecosystem service of global importance. Not only sexual reproduction of plants is ensured, but also yields are stabilized and genetic variability of crops is maintained, counteracting inbreeding depression and facilitating system resilience. While experiencing rapid environmental change, there is an increased demand for food and income security, especially in sub-Saharan communities, which are highly dependent on small scale agriculture. By combining exclusion experiments, pollinator surveys and field manipulations, this study for the first time quantifies the contribution of bee pollinators to smallholders' production of the major cash crops, cotton and sesame, in Burkina Faso. Pollination by honeybees and wild bees significantly increased yield quantity and quality on average up to 62%, while exclusion of pollinators caused an average yield gap of 37% in cotton and 59% in sesame. Self-pollination revealed inbreeding depression effects on fruit set and low germination rates in the F1-generation. Our results highlight potential negative consequences of any pollinator decline, provoking risks to agriculture and compromising crop yields in sub-Saharan West Africa.

  4. Separating selection by diurnal and nocturnal pollinators on floral display and spur length in Gymnadenia conopsea.

    Science.gov (United States)

    Sletvold, Nina; Trunschke, Judith; Wimmergren, Carolina; Agren, Jon

    2012-08-01

    Most plants attract multiple flower visitors that may vary widely in their effectiveness as pollinators. Floral evolution is expected to reflect interactions with the most important pollinators, but few studies have quantified the contribution of different pollinators to current selection on floral traits. To compare selection mediated by diurnal and nocturnal pollinators on floral display and spur length in the rewarding orchid Gymnadenia conopsea, we manipulated the environment by conducting supplemental hand-pollinations and selective pollinator exclusions in two populations in central Norway. In both populations, the exclusion of diurnal pollinators significantly reduced seed production compared to open pollination, whereas the exclusion of nocturnal pollinators did not. There was significant selection on traits expected to influence pollinator attraction and pollination efficiency in both the diurnal and nocturnal pollination treatment. The relative strength of selection among plants exposed to diurnal and nocturnal visitors varied among traits and populations, but the direction of selection was consistent. The results suggest that diurnal pollinators are more important than nocturnal pollinators for seed production in the study populations, but that both categories contribute to selection on floral morphology. The study illustrates how experimental manipulations can link specific categories of pollinators to observed selection on floral traits, and thus improve our understanding of how species interactions shape patterns of selection.

  5. Two bee-pollinated plant species show higher seed production when grown in gardens compared to arable farmland.

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    John Cussans

    2010-07-01

    Full Text Available Insect pollinator abundance, in particular that of bees, has been shown to be high where there is a super-abundance of floral resources; for example in association with mass-flowering crops and also in gardens where flowering plants are often densely planted. Since land management affects pollinator numbers, it is also likely to affect the resultant pollination of plants growing in these habitats. We hypothesised that the seed or fruit set of two plant species, typically pollinated by bumblebees and/or honeybees might respond in one of two ways: 1 pollination success could be reduced when growing in a floriferous environment, via competition for pollinators, or 2 pollination success could be enhanced because of increased pollinator abundance in the vicinity.We compared the pollination success of experimental plants of Glechoma hederacea L. and Lotus corniculatus L. growing in gardens and arable farmland. On the farms, the plants were placed either next to a mass-flowering crop (oilseed rape, Brassica napus L. or field beans, Vicia faba L. or next to a cereal crop (wheat, Triticum spp.. Seed set of G. hederacea and fruit set of L. corniculatus were significantly higher in gardens compared to arable farmland. There was no significant difference in pollination success of G. hederacea when grown next to different crops, but for L. corniculatus, fruit set was higher in the plants growing next to oilseed rape when the crop was in flower.The results show that pollination services can limit fruit set of wild plants in arable farmland, but there is some evidence that the presence of a flowering crop can facilitate their pollination (depending on species and season. We have also demonstrated that gardens are not only beneficial to pollinators, but also to the process of pollination.

  6. Pollinator scarcity drives the shift to delayed selfing in Himalayan mayapple Podophyllum hexandrum (Berberidaceae)

    Science.gov (United States)

    Xiong, Ying-Ze; Fang, Qiang; Huang, Shuang-Quan

    2013-01-01

    Recent molecular phylogenetics have indicated that American mayapple (mainly self-incompatible, SI) and Himalayan mayapple, which was considered to be self-compatible (SC), are sister species with disjunct distribution between eastern Asia and eastern North America. We test a hypothesis that the persistence of this early spring flowering herb in the Himalayan region is attributable to the transition from SI to SC, the capacity for selfing in an unpredictable pollination environment. Pollinator observations were conducted in an alpine meadow with hundreds of Himalayan mayapple (Podophyllum hexandrum Royle) individuals over 2 years. To examine autogamy, seed set under different pollination treatments was compared. To clarify whether automatic self-pollination is achieved by movement of the pistil as a previous study suggested, we measured incline angles of the pistil and observed flower movement during anthesis using video. Floral visitors to the nectarless flowers were very rare, but solitary bees and honeybees could be potential pollinators. Seed set of bagged flowers was not significantly different from that of open-pollinated, self- or cross-pollinated flowers. However, removal of petals or stamens lowered seed yield. The angles of inclination of pistils did not change during the process of pollination. Automatic self-pollination was facilitated by petals closing and stamens moving simultaneously to contact the stigma. Stigmatic pollen load increased little during the day time, in contrast to a sharp increase when the flowers closed during the night-time. These observations indicated that Himalayan mayapple was SC and delayed self-pollination was facilitated by the movement of petals rather than the pistil. Compared with SI American mayapple, no obvious inbreeding depression in SC Himalayan mayapple may contribute its existence in the uplifting zone. A scarcity of pollinators may have driven the shift to delayed selfing in P. hexandrum.

  7. Impact of honeybee (Apis mellifera L. density on wild bee foraging behaviour

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    Goras Georgios

    2016-06-01

    Full Text Available Honey bees are globally regarded as important crop pollinators and are also valued for their honey production. They have been introduced on an almost worldwide scale. During recent years, however, several studies argue their possible competition with unmanaged pollinators. Here we examine the possible effects of honey bees on the foraging behaviour of wild bees on Cistus creticus flowers in Northern Greece. We gradually introduced one, five, and eight honey-bee hives per site, each containing ca. 20,000 workers. The visitation frequency and visit duration of wild bees before and after the beehive introductions were measured by flower observation. While the visitation frequencies of wild bees were unaffected, the average time wild bees spent on C. creticus increased with the introduction of the honey-bee hives. Although competition between honey bees and wild bees is often expected, we did not find any clear evidence for significant effects even in honey-bee densities much higher than the European-wide average of 3.1 colonies/km2.

  8. Impact of chronic neonicotinoid exposure on honeybee colony performance and queen supersedure.

    Directory of Open Access Journals (Sweden)

    Christoph Sandrock

    Full Text Available BACKGROUND: Honeybees provide economically and ecologically vital pollination services to crops and wild plants. During the last decade elevated colony losses have been documented in Europe and North America. Despite growing consensus on the involvement of multiple causal factors, the underlying interactions impacting on honeybee health and colony failure are not fully resolved. Parasites and pathogens are among the main candidates, but sublethal exposure to widespread agricultural pesticides may also affect bees. METHODOLOGY/PRINCIPAL FINDINGS: To investigate effects of sublethal dietary neonicotinoid exposure on honeybee colony performance, a fully crossed experimental design was implemented using 24 colonies, including sister-queens from two different strains, and experimental in-hive pollen feeding with or without environmentally relevant concentrations of thiamethoxam and clothianidin. Honeybee colonies chronically exposed to both neonicotinoids over two brood cycles exhibited decreased performance in the short-term resulting in declining numbers of adult bees (-28% and brood (-13%, as well as a reduction in honey production (-29% and pollen collections (-19%, but colonies recovered in the medium-term and overwintered successfully. However, significantly decelerated growth of neonicotinoid-exposed colonies during the following spring was associated with queen failure, revealing previously undocumented long-term impacts of neonicotinoids: queen supersedure was observed for 60% of the neonicotinoid-exposed colonies within a one year period, but not for control colonies. Linked to this, neonicotinoid exposure was significantly associated with a reduced propensity to swarm during the next spring. Both short-term and long-term effects of neonicotinoids on colony performance were significantly influenced by the honeybees' genetic background. CONCLUSIONS/SIGNIFICANCE: Sublethal neonicotinoid exposure did not provoke increased winter losses. Yet

  9. Barbs Facilitate the Helical Penetration of Honeybee (Apis mellifera ligustica) Stingers

    OpenAIRE

    Wu, Jianing; Yan, Shaoze; Zhao, Jieliang; Ye, Yuying

    2014-01-01

    The stinger is a very small and efficient device that allows honeybees to perform two main physiological activities: repelling enemies and laying eggs for reproduction. In this study, we explored the specific characteristics of stinger penetration, where we focused on its movements and the effects of it microstructure. The stingers of Italian honeybees (Apis mellifera ligustica) were grouped and fixed onto four types of cubic substrates, before pressing into different substrates. The morpholo...

  10. The biochemistry and genetics of floral scent production as part of the petunia pollination syndrome

    NARCIS (Netherlands)

    Shaipulah, N.F.M.

    2018-01-01

    Floral scent plays a major role in flower discrimination by pollinators in the Petunia genus. By providing specific signals to pollinators, floral scent can significantly contribute to the plant pollination efficiency and reproductive success. Fragrant petunias mostly emit volatile benzenoids and

  11. Threatened pollination systems in native flora of the Ogasawara (Bonin) Islands.

    Science.gov (United States)

    Abe, Tetsuto

    2006-08-01

    Various alien species have been introduced to the Ogasawara Islands (Japan). A survey was made investigating whether the native pollination systems fit an 'island syndrome' (biasing the flora to dioecy, with subdued, inconspicuous flowers) and whether alien species have disrupted the native pollination network. Flower visitors and floral traits were determined in the field (12 islands) and from the literature. Associations among floral traits such as sexual expression, flower colour and flower shape were tested. Among the 269 native flowering plants, 74.7 % are hermaphroditic, 13.0 % are dioecious and 7.1 % are monoecious. Classification by flower colour revealed that 36.0 % were white, 21.6 % green and 13.8 % yellow. Woody species (trees and shrubs) comprised 36.5 % of the flora and were associated with dioecy and white flowers. Solitary, endemic small bees were the dominant flower visitors and visited 66.7 % of the observed species on satellite islands where the native pollination networks are preserved. In contrast to the situation on the satellite islands, introduced honeybees were the most dominant pollinator (visiting 60.1 % of observed species) on the two main islands, Chichi-jima and Haha-jima, and had spread to satellite islands near Chichi-jima Island. The island syndrome for pollination systems in the Ogasawara Islands was evident in a high percentage of dioecious species, the subdued colour of the native flora and solitary flower visitors on satellite islands. The shape and colour adaptations of several flowers suggested native pollination niches for long-proboscis moths and carpenter bees. However, the domination and expansion of introduced honeybees have the potential for disruption of the native pollination network in the two main, and several satellite, islands of the Ogasawara Islands.

  12. 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.

  13. Honeybee immunity and colony losses

    Directory of Open Access Journals (Sweden)

    F. Nazzi

    2014-10-01

    Full Text Available The decline of honeybee colonies and their eventual collapse is a widespread phenomenon in the Northern hemisphere of the globe, which severely limits the beekeeping industry. This dramatic event is associated with an enhanced impact of parasites and pathogens on honeybees, which is indicative of reduced immunocompetence. The parasitic mite Varroa destructor and the vectored viral pathogens appear to play a key-role in the induction of this complex syndrome. In particular, the Deformed Wing Virus (DWV is widespread and is now considered, along with Varroa, one of the major causes of bee colony losses. Several lines of evidence indicate that this mite/DWV association severely affects the immune system of honeybees and makes them more sensitive to the action of other stress factors. The molecular mechanisms underpinning these complex interactions are currently being investigated and the emerging information has allowed the development of a new functional model, describing how different stress factors may synergistically concur in the induction of bee immune alteration and health decline. This provides a new logical framework in which to interpret the proposed multifactorial origin of bee colony losses and sets the stage for a more comprehensive and integrated analysis of the effect that multiple stress agents may have on honeybees.

  14. Honeybee odometry and scent guidance

    NARCIS (Netherlands)

    Vladusich, T; Hemmi, JM; Zeil, J

    2006-01-01

    We report on a striking asymmetry in search behaviour observed in honeybees trained to forage alternately at one of two feeder sites in a narrow tunnel. Bees were trained by periodically switching the position of a sucrose reward between relatively short and long distances in the tunnel. Search

  15. Barbs facilitate the helical penetration of honeybee (Apis mellifera ligustica stingers.

    Directory of Open Access Journals (Sweden)

    Jianing Wu

    Full Text Available The stinger is a very small and efficient device that allows honeybees to perform two main physiological activities: repelling enemies and laying eggs for reproduction. In this study, we explored the specific characteristics of stinger penetration, where we focused on its movements and the effects of it microstructure. The stingers of Italian honeybees (Apis mellifera ligustica were grouped and fixed onto four types of cubic substrates, before pressing into different substrates. The morphological characteristics of the stinger cross-sections were analyzed before and after penetration by microscopy. Our findings suggest that the honeybee stinger undergoes helical and clockwise rotation during penetration. We also found that the helical penetration of the stinger is associated directly with the spiral distribution of the barbs, thereby confirming that stinger penetration involves an advanced microstructure rather than a simple needle-like apparatus. These results provide new insights into the mechanism of honeybee stinger penetration.

  16. Barbs facilitate the helical penetration of honeybee (Apis mellifera ligustica) stingers.

    Science.gov (United States)

    Wu, Jianing; Yan, Shaoze; Zhao, Jieliang; Ye, Yuying

    2014-01-01

    The stinger is a very small and efficient device that allows honeybees to perform two main physiological activities: repelling enemies and laying eggs for reproduction. In this study, we explored the specific characteristics of stinger penetration, where we focused on its movements and the effects of it microstructure. The stingers of Italian honeybees (Apis mellifera ligustica) were grouped and fixed onto four types of cubic substrates, before pressing into different substrates. The morphological characteristics of the stinger cross-sections were analyzed before and after penetration by microscopy. Our findings suggest that the honeybee stinger undergoes helical and clockwise rotation during penetration. We also found that the helical penetration of the stinger is associated directly with the spiral distribution of the barbs, thereby confirming that stinger penetration involves an advanced microstructure rather than a simple needle-like apparatus. These results provide new insights into the mechanism of honeybee stinger penetration.

  17. 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

  18. Spider Movement, UV Reflectance and Size, but Not Spider Crypsis, Affect the Response of Honeybees to Australian Crab Spiders

    Science.gov (United States)

    Llandres, Ana L.; Rodríguez-Gironés, Miguel A.

    2011-01-01

    According to the crypsis hypothesis, the ability of female crab spiders to change body colour and match the colour of flowers has been selected because flower visitors are less likely to detect spiders that match the colour of the flowers used as hunting platform. However, recent findings suggest that spider crypsis plays a minor role in predator detection and some studies even showed that pollinators can become attracted to flowers harbouring Australian crab spider when the UV contrast between spider and flower increases. Here we studied the response of Apis mellifera honeybees to the presence of white or yellow Thomisus spectabilis Australian crab spiders sitting on Bidens alba inflorescences and also the response of honeybees to crab spiders that we made easily detectable painting blue their forelimbs or abdomen. To account for the visual systems of crab spider's prey, we measured the reflectance properties of the spiders and inflorescences used for the experiments. We found that honeybees did not respond to the degree of matching between spiders and inflorescences (either chromatic or achromatic contrast): they responded similarly to white and yellow spiders, to control and painted spiders. However spider UV reflection, spider size and spider movement determined honeybee behaviour: the probability that honeybees landed on spider-harbouring inflorescences was greatest when the spiders were large and had high UV reflectance or when spiders were small and reflected little UV, and honeybees were more likely to reject inflorescences if spiders moved as the bee approached the inflorescence. Our study suggests that only the large, but not the small Australian crab spiders deceive their preys by reflecting UV light, and highlights the importance of other cues that elicited an anti-predator response in honeybees. PMID:21359183

  19. Spider movement, UV reflectance and size, but not spider crypsis, affect the response of honeybees to Australian crab spiders.

    Science.gov (United States)

    Llandres, Ana L; Rodríguez-Gironés, Miguel A

    2011-02-16

    According to the crypsis hypothesis, the ability of female crab spiders to change body colour and match the colour of flowers has been selected because flower visitors are less likely to detect spiders that match the colour of the flowers used as hunting platform. However, recent findings suggest that spider crypsis plays a minor role in predator detection and some studies even showed that pollinators can become attracted to flowers harbouring Australian crab spider when the UV contrast between spider and flower increases. Here we studied the response of Apis mellifera honeybees to the presence of white or yellow Thomisus spectabilis Australian crab spiders sitting on Bidens alba inflorescences and also the response of honeybees to crab spiders that we made easily detectable painting blue their forelimbs or abdomen. To account for the visual systems of crab spider's prey, we measured the reflectance properties of the spiders and inflorescences used for the experiments. We found that honeybees did not respond to the degree of matching between spiders and inflorescences (either chromatic or achromatic contrast): they responded similarly to white and yellow spiders, to control and painted spiders. However spider UV reflection, spider size and spider movement determined honeybee behaviour: the probability that honeybees landed on spider-harbouring inflorescences was greatest when the spiders were large and had high UV reflectance or when spiders were small and reflected little UV, and honeybees were more likely to reject inflorescences if spiders moved as the bee approached the inflorescence. Our study suggests that only the large, but not the small Australian crab spiders deceive their preys by reflecting UV light, and highlights the importance of other cues that elicited an anti-predator response in honeybees.

  20. 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

  1. 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.

  2. Insects, birds and lizards as pollinators of the largest-flowered Scrophularia of Europe and Macaronesia.

    Science.gov (United States)

    Ortega-Olivencia, Ana; Rodríguez-Riaño, Tomás; Pérez-Bote, José L; López, Josefa; Mayo, Carlos; Valtueña, Francisco J; Navarro-Pérez, Marisa

    2012-01-01

    It has traditionally been considered that the flowers of Scrophularia are mainly pollinated by wasps. We studied the pollination system of four species which stand out for their large and showy flowers: S. sambucifolia and S. grandiflora (endemics of the western Mediterranean region), S. trifoliata (an endemic of the Tyrrhenian islands) and S. calliantha (an endemic of the Canary Islands). Our principal aim was to test whether these species were pollinated by birds or showed a mixed pollination system between insects and birds. Censuses and captures of insects and birds were performed to obtain pollen load transported and deposited on the stigmas. Also, a qualitative and quantitative analysis of the flowers and inflorescences was carried out. Flowers were visited by Hymenoptera and by passerine birds. The Canarian species was the most visited by birds, especially by Phylloscopus canariensis, and its flowers were also accessed by juveniles of the lizard Gallotia stehlini. The most important birds in the other three species were Sylvia melanocephala and S. atricapilla. The most important insect-functional groups in the mixed pollination system were: honey-bees and wasps in S. sambucifolia; bumble-bees and wasps in S. grandiflora; wasps in S. trifoliata; and a small bee in S. calliantha. The species studied show a mixed pollination system between insects and passerine birds. In S. calliantha there is, in addition, a third agent (juveniles of Gallotia stehlini). The participation of birds in this mixed pollination system presents varying degrees of importance because, while in S. calliantha they are the main pollinators, in the other species they interact to complement the insects which are the main pollinators. A review of different florae showed that the large showy floral morphotypes of Scrophularia are concentrated in the western and central Mediterranean region, Macaronesia and USA (New Mexico).

  3. Floral scent composition predicts bee pollination system in five butterfly bush (Buddleja, Scrophulariaceae) species.

    Science.gov (United States)

    Gong, W-C; Chen, G; Vereecken, N J; Dunn, B L; Ma, Y-P; Sun, W-B

    2015-01-01

    Traditionally, plant-pollinator interactions have been interpreted as pollination syndrome. However, the validity of pollination syndrome has been widely doubted in modern studies of pollination ecology. The pollination ecology of five Asian Buddleja species, B. asiatica, B. crispa, B. forrestii, B. macrostachya and B. myriantha, in the Sino-Himalayan region in Asia, flowering in different local seasons, with scented inflorescences were investigated during 2011 and 2012. These five species exhibited diverse floral traits, with narrow and long corolla tubes and concealed nectar. According to their floral morphology, larger bees and Lepidoptera were expected to be the major pollinators. However, field observations showed that only larger bees (honeybee/bumblebee) were the primary pollinators, ranging from 77.95% to 97.90% of total visits. In this study, floral scents of each species were also analysed using coupled gas chromatography and mass spectrometry (GC-MS). Although the five Buddleja species emitted differentiated floral scent compositions, our results showed that floral scents of the five species are dominated by substances that can serve as attractive signals to bees, including species-specific scent compounds and principal compounds with larger relative amounts. This suggests that floral scent compositions are closely associated with the principal pollinator assemblages in these five species. Therefore, we conclude that floral scent compositions rather than floral morphology traits should be used to interpret plant-pollinator interactions in these Asian Buddleja species. © 2014 German Botanical Society and The Royal Botanical Society of the Netherlands.

  4. Molecular recognition of floral volatile with two olfactory related proteins in the Eastern honeybee (Apis cerana).

    Science.gov (United States)

    Li, Hongliang; Zhang, Linya; Ni, Cuixia; Shang, Hanwu; Zhuang, Shulin; Li, Jianke

    2013-05-01

    The honeybee relies on its sensitive olfaction to perform the foraging activities in the field. In the antennal chemoreception system of honeybee, odorant-binding proteins (OBPs) and chemosensory protein (CSPs) are major two protein families capable of binding with some plant volatiles and chemical ligands. However, the chemical binding interaction of plant odors with OBPs and CSPs in the honeybee olfactory system is still not clear yet. Hence, complex fluorescent spectra, ultraviolet absorption spectra, circular dichroism spectra and molecular docking were used to investigate the binding property of AcerASP2 (an OBP of Apis cerana) and AcerASP3 (a CSP of Apis cerana) with β-ionone, one of ordinary floral volatiles in botanical flower. As a result, β-ionone had a strong capability to quench the fluorescence that the two proteins produced, and their interaction was a dynamic process that was mainly driven by a hydrophobic force. AcerASP2 had a larger hydrophobic cavity than that of AcerASP3 and the conformation of AcerASP2 was changed less than AcerASP3 when binding with β-ionone. Our data suggests that OBPs like AcerASP2 might make a large contribution toward assisting the honeybee in sensing and foraging flowers, and A. cerana has evolved a good circadian rhythm to perceive a flower's odor following the fluctuation of temperature in the olfactory system. This significantly extends our knowledge on how to strengthen the honeybees' pollination service via manipulation of target proteins in the olfactory system. Copyright © 2013 Elsevier B.V. All rights reserved.

  5. Importance of bee pollination for cotton production in conventional and organic farms in Brazil

    Directory of Open Access Journals (Sweden)

    Viviane C. Pires

    2014-08-01

    Full Text Available This study aimed to evaluate the importance of wild bee and feral honeybee visits for cotton production on conventional and organic farms. Experiments were conducted in Brazil, on a conventional cotton farm in Mato Grosso state in the Amazon biome and on an organic farm in Paraíba state in the Caatinga biome. On the conventional farm, bee assemblage and cotton production were measured near to and far from natural vegetation. Bee richness, fibre fraction, seed number and yield (Kg/ha were higher by 57.14, 1.95, 17.77 and 18.44% respectively in plots near natural vegetation, but bee abundance did not vary with distance to natural vegetation. On the organic farm, because the cropping area is surrounded by natural vegetation, pollination deficit was evaluated using an exclusion experiment where cotton production of flowers bagged to prevent bee visitation (spontaneous self-pollination was compared to production of flowers open to bee visitation (open pollination. Open pollinated flowers had higher average boll weight, fibre weight and seed number. Although cotton is not directly dependent on bee pollination, bees increased cotton production on the organic farm by more than 12% for fibre weight and over 17% for seed number. Our data confirm the importance of maintaining communities of pollinators on cotton farms, especially for organic production.

  6. 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...... 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...... 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...

  7. Honeybee health in South America

    OpenAIRE

    Maggi , Matías; Antúnez , Karina; Invernizzi , Ciro; Aldea , Patricia; Vargas , Marisol; Negri , Pedro; Brasesco , Constanza; De Jong , David; Message , Dejair; Teixeira , Erica Weinstein; Principal , Judith; Barrios , Carlos; Ruffinengo , Sergio; Da Silva , Rafael Rodríguez; Eguaras , Martín

    2016-01-01

    International audience; AbstractHoneybees are essential components to modern agriculture and economy. However, a continuous increase in cases of colony losses and colony depopulation are being reported worldwide. This critical situation has put the fragile equilibrium between bees and plants on the edge. As a consequence, several scientists have begun to focus their lines of research on this issue. Most researchers agree that there is no single explanation for the observed colony losses. Inst...

  8. 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.

  9. Development of molecular tools for honeybee virus research: the ...

    African Journals Online (AJOL)

    Increasing knowledge of the association of honeybee viruses with other honeybee parasites, primarily the ectoparasitic mite Varroa destructor, and their implication in the mass mortality of honeybee colonies, has resulted in increasing awareness and interest in honeybee viruses. In addition the identification, monitoring and ...

  10. You'd better walk alone: Changes in forest composition affect pollination efficiency and pre-dispersal cone damage in Iberian Juniperus thurifera forests.

    Science.gov (United States)

    Rodríguez-García, E; Mezquida, E T; Olano, J M

    2017-11-01

    Changes in land-use patterns are a major driver of global environmental change. Cessation of traditional land-use practices has led to forest expansion and shifts in forest composition. Consequently, former monospecific forests maintained by traditional management are progressing towards mixed forests. However, knowledge is scarce on how the presence of other tree species will affect reproduction of formerly dominant species. We explored this question in the wind-pollinated tree Juniperus thurifera. We hypothesised that the presence of heterospecific trees would have a negative effect on cone production and on the proportion of cones attacked by specialised predators. We assessed the relative importance of forest composition on cone production, seed development and pre-dispersal cone damage on nine paired pure and mixed J. thurifera forests in three regions across the Iberian Peninsula. The effects of forest composition on crop size, cone and seed characteristics, as well as damage by pre-dispersal arthropods were tested using mixed models. Cone production was lower and seed abortion higher in mixed forests, suggesting higher pollination failure. In contrast, cone damage by arthropods was higher in pure forests, supporting the hypothesis that presence of non-host plants reduces damage rates. However, the response of each arthropod to forest composition was species-specific and the relative rates of cone damage varied depending on individual tree crops. Larger crop sizes in pure forests compensated for the higher cone damage rates, leading to a higher net production of sound seeds compared to mixed forests. This study indicates that ongoing changes in forest composition after land abandonment may impact tree reproduction. © 2017 German Society for Plant Sciences and The Royal Botanical Society of the Netherlands.

  11. Wild bees enhance honey bees’ pollination of hybrid sunflower

    Science.gov (United States)

    Greenleaf, Sarah S.; Kremen, Claire

    2006-01-01

    Pollinators are required for producing 15–30% of the human food supply, and farmers rely on managed honey bees throughout the world to provide these services. Yet honey bees are not always the most efficient pollinators of all crops and are declining in various parts of the world. Crop pollination shortages are becoming increasingly common. We found that behavioral interactions between wild and honey bees increase the pollination efficiency of honey bees on hybrid sunflower up to 5-fold, effectively doubling honey bee pollination services on the average field. These indirect contributions caused by interspecific interactions between wild and honey bees were more than five times more important than the contributions wild bees make to sunflower pollination directly. Both proximity to natural habitat and crop planting practices were significantly correlated with pollination services provided directly and indirectly by wild bees. Our results suggest that conserving wild habitat at the landscape scale and altering selected farm management techniques could increase hybrid sunflower production. These findings also demonstrate the economic importance of interspecific interactions for ecosystem services and suggest that protecting wild bee populations can help buffer the human food supply from honey bee shortages. PMID:16940358

  12. Wild bees enhance honey bees' pollination of hybrid sunflower.

    Science.gov (United States)

    Greenleaf, Sarah S; Kremen, Claire

    2006-09-12

    Pollinators are required for producing 15-30% of the human food supply, and farmers rely on managed honey bees throughout the world to provide these services. Yet honey bees are not always the most efficient pollinators of all crops and are declining in various parts of the world. Crop pollination shortages are becoming increasingly common. We found that behavioral interactions between wild and honey bees increase the pollination efficiency of honey bees on hybrid sunflower up to 5-fold, effectively doubling honey bee pollination services on the average field. These indirect contributions caused by interspecific interactions between wild and honey bees were more than five times more important than the contributions wild bees make to sunflower pollination directly. Both proximity to natural habitat and crop planting practices were significantly correlated with pollination services provided directly and indirectly by wild bees. Our results suggest that conserving wild habitat at the landscape scale and altering selected farm management techniques could increase hybrid sunflower production. These findings also demonstrate the economic importance of interspecific interactions for ecosystem services and suggest that protecting wild bee populations can help buffer the human food supply from honey bee shortages.

  13. Floral function: effects of traits on pollinators, male and female pollination success, and female fitness across three species of milkweeds (Asclepias).

    Science.gov (United States)

    La Rosa, Raffica J; Conner, Jeffrey K

    2017-01-01

    Central questions in plant reproductive ecology are whether the functions of floral traits in hermaphrodites create conflict between sexes that could slow evolution, and whether individual floral traits function in pollinator attraction, efficiency, or both. We studied how floral traits affect pollinator visitation and efficiency, and how they affect male and female function and female fitness within and across three Asclepias species that differ in floral morphology. Using separate multiple regressions, we regressed pollen removal, deposition, and fruit number onto six floral traits. We also used path analyses integrating these variables with pollinator visitation data for two of the species to further explore floral function and its effects on fruit production. Most traits affected male pollination success only, and these effects often differed between species. The exception was increased slit length, which increased pollinia insertion in two of the species. There were no interspecific differences in the effects of the traits on female pollination success. All traits except horn reach affected pollination efficiency in at least one species, and horn reach and two hood dimensions were the only traits to affect pollinator attraction, but in just one species. Traits tended to function in only one sex, and more traits affected function through pollinator efficiency than through attraction. There was no significant link between female pollination success and female fitness in any of the three species; this pattern is consistent with fruit production not being limited by pollen deposition. © 2017 Botanical Society of America.

  14. Interpatch foraging in honeybees-rational decision making at secondary hubs based upon time and motivation.

    Science.gov (United States)

    Najera, Daniel A; McCullough, Erin L; Jander, Rudolf

    2012-11-01

    For honeybees, Apis mellifera, the hive has been well known to function as a primary decision-making hub, a place from which foragers decide among various directions, distances, and times of day to forage efficiently. Whether foraging honeybees can make similarly complex navigational decisions from locations away from the hive is unknown. To examine whether or not such secondary decision-making hubs exist, we trained bees to forage at four different locations. Specifically, we trained honeybees to first forage to a distal site "CT" 100 m away from the hive; if food was present, they fed and then chose to go home. If food was not present, the honeybees were trained to forage to three auxiliary sites, each at a different time of the day: A in the morning, B at noon, and C in the afternoon. The foragers learned to check site CT for food first and then efficiently depart to the correct location based upon the time of day if there was no food at site CT. Thus, the honeybees were able to cognitively map motivation, time, and five different locations (Hive, CT, A, B, and C) in two spatial dimensions; these are the contents of the cognitive map used by the honeybees here. While at site CT, we verified that the honeybees could choose between 4 different directions (to A, B, C, and the Hive) and thus label it as a secondary decision-making hub. The observed decision making uncovered here is inferred to constitute genuine logical operations, involving a branched structure, based upon the premises of motivational state, and spatiotemporal knowledge.

  15. Molecular mechanisms underlying formation of long-term reward memories and extinction memories in the honeybee (Apis mellifera)

    Science.gov (United States)

    2014-01-01

    The honeybee (Apis mellifera) has long served as an invertebrate model organism for reward learning and memory research. Its capacity for learning and memory formation is rooted in the ecological need to efficiently collect nectar and pollen during summer to ensure survival of the hive during winter. Foraging bees learn to associate a flower's characteristic features with a reward in a way that resembles olfactory appetitive classical conditioning, a learning paradigm that is used to study mechanisms underlying learning and memory formation in the honeybee. Due to a plethora of studies on appetitive classical conditioning and phenomena related to it, the honeybee is one of the best characterized invertebrate model organisms from a learning psychological point of view. Moreover, classical conditioning and associated behavioral phenomena are surprisingly similar in honeybees and vertebrates, suggesting a convergence of underlying neuronal processes, including the molecular mechanisms that contribute to them. Here I review current thinking on the molecular mechanisms underlying long-term memory (LTM) formation in honeybees following classical conditioning and extinction, demonstrating that an in-depth analysis of the molecular mechanisms of classical conditioning in honeybees might add to our understanding of associative learning in honeybees and vertebrates. PMID:25225299

  16. Field margins, foraging distances and their impacts on nesting pollinator success.

    Directory of Open Access Journals (Sweden)

    Sean A Rands

    Full Text Available The areas of wild land around the edges of agricultural fields are a vital resource for many species. These include insect pollinators, to whom field margins provide both nest sites and important resources (especially when adjacent crops are not in flower. Nesting pollinators travel relatively short distances from the nest to forage: most species of bee are known to travel less than two kilometres away. In order to ensure that these pollinators have sufficient areas of wild land within reach of their nests, agricultural landscapes need to be designed to accommodate the limited travelling distances of nesting pollinators. We used a spatially-explicit modelling approach to consider whether increasing the width of wild strips of land within the agricultural landscape will enhance the amount of wild resources available to a nesting pollinator, and if it would impact differently on pollinators with differing foraging strategies. This was done both by creating field structures with a randomised geography, and by using landscape data based upon the British agricultural landscape. These models demonstrate that enhancing field margins should lead to an increase in the availability of forage to pollinators that nest within the landscape. With the exception of species that only forage within a very short range of their nest (less than 125 m, a given amount of field margin manipulation should enhance the proportion of land available to a pollinator for foraging regardless of the distance over which it normally travels to find food. A fixed amount of field edge manipulation should therefore be equally beneficial for both longer-distance nesting foragers such as honeybees, and short-distance foragers such as solitary bees.

  17. 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.

  18. Reproductive biology and nectar secretion dynamics of Penstemon gentianoides (Plantaginaceae: a perennial herb with a mixed pollination system?

    Directory of Open Access Journals (Sweden)

    Lucía Salas-Arcos

    2017-08-01

    Full Text Available Background In many plant species, pollination syndromes predict the most effective pollinator. However, other floral visitors may also offer effective pollination services and promote mixed pollination systems. Several species of the species-rich Penstemon (Plantaginaceae exhibit a suite of floral traits that suggest adaptation for pollination by both hymenopterans and hummingbirds. Transitions from the ancestral hymenopteran pollination syndrome to more derived hummingbird pollination syndrome may be promoted if the quantity or quality of visits by hummingbirds is increased and if the ancestral pollinator group performs less efficiently. The quantification of such shifts in pollination systems in the group is still limited. We aimed to investigate floral traits linked to this pollination syndrome in Penstemon gentianoides with flowers visited by bumblebees and hummingbirds. Methods We investigated the floral biology, pollinator assemblages, breeding system and nectar production patterns ofP. gentianoides inhabiting a temperate montane forest in central Mexico. Pollination experiments were also conducted to assess the pollinator effectiveness of bumblebees and hummingbirds. Results P. gentianoides flowers are protandrous, with 8-d male phase (staminate flowers, followed by the ∼1–7 d female phase (pistillate phase. Flowers display traits associated with hymenopteran pollination, including purple flowers abruptly ampliate-ventricose to a broad throat with anthers and stigmas included, and long lifespans. However, the nectar available in the morning hours was abundant and dilute, traits linked to flowers with a hummingbird pollination syndrome. Two hummingbird species made most of the visits to flowers, Selasphorus platycercus (30.3% of all visits, followed by Archilochus colubris (11.3%. Bumblebees (Bombus ephippiatus, B. huntii and B. weisi accounted for 51.8% of all recorded visits, but their foraging activity was restricted to the warmer

  19. 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.

  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. Resolution and sensitivity of the eyes of the Asian honeybees Apis florea, Apis cerana and Apis dorsata.

    Science.gov (United States)

    Somanathan, Hema; Warrant, Eric J; Borges, Renee M; Wallén, Rita; Kelber, Almut

    2009-08-01

    Bees of the genus Apis are important foragers of nectar and pollen resources. Although the European honeybee, Apis mellifera, has been well studied with respect to its sensory abilities, learning behaviour and role as pollinators, much less is known about the other Apis species. We studied the anatomical spatial resolution and absolute sensitivity of the eyes of three sympatric species of Asian honeybees, Apis cerana, Apis florea and Apis dorsata and compared them with the eyes of A. mellifera. Of these four species, the giant honeybee A. dorsata (which forages during moonlit nights) has the lowest spatial resolution and the most sensitive eyes, followed by A. mellifera, A. cerana and the dwarf honeybee, A. florea (which has the smallest acceptance angles and the least sensitive eyes). Moreover, unlike the strictly diurnal A. cerana and A. florea, A. dorsata possess large ocelli, a feature that it shares with all dim-light bees. However, the eyes of the facultatively nocturnal A. dorsata are much less sensitive than those of known obligately nocturnal bees such as Megalopta genalis in Panama and Xylocopa tranquebarica in India. The differences in sensitivity between the eyes of A. dorsata and other strictly diurnal Apis species cannot alone explain why the former is able to fly, orient and forage at half-moon light levels. We assume that additional neuronal adaptations, as has been proposed for A. mellifera, M. genalis and X. tranquebarica, might exist in A. dorsata.

  2. 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...... with either latitude or elevation. However, network modularity decreased significantly with latitude whereas mean number of links per plant species (Lp) and A/P ratio peaked at mid-latitude. Above 500 m a.s.l., A/P ratio decreased and mean number of links per pollinator species (La) increased with elevation......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...

  3. The dilemma of being a fragrant flower: the major floral volatile attracts pollinators and florivores in the euglossine-pollinated orchid Dichaea pendula.

    Science.gov (United States)

    Nunes, Carlos E P; Peñaflor, Maria Fernanda G V; Bento, José Maurício S; Salvador, Marcos José; Sazima, Marlies

    2016-12-01

    Volatile organic compounds (VOCs) mediate both mutualistic and antagonistic plant-animal interactions; thus, the attraction of mutualists and antagonists by floral VOCs constitutes an important trade-off in the evolutionary ecology of angiosperms. Here, we evaluate the role of VOCs in mediating communication between the plant and its mutualist and antagonist floral visitors. To assess the evolutionary consequences of VOC-mediated signalling to distinct floral visitors, we studied the reproductive ecology of Dichaea pendula, assessing the effects of florivores on fruit set, the pollination efficiency of pollinators and florivores, the floral scent composition and the attractiveness of the major VOC to pollinators and florivores. The orchid depends entirely on orchid-bees for sexual reproduction, and the major florivores, the weevils, feed on corollas causing self-pollination, triggering abortion of 26.4 % of the flowers. Floral scent was composed of approximately 99 % 2-methoxy-4-vinylphenol, an unusual floral VOC attractive to pollinators and florivores. The low fruit set from natural pollination (5.6 %) compared to hand cross-pollination (45.5 %) and low level of pollinator visitation [0.02 visits (flower hour) -1 ] represent the limitations to pollination. Our research found that 2-methoxy-4-vinylphenol mediates both mutualistic and antagonistic interactions, which could result in contrary evolutionary pressures on novo-emission. The scarcity of pollinators, not florivory, was the major constraint to fruit set. Our results suggest that, rather than anti-florivory adaptations, adaptations to enhance pollinator attraction and cross-pollination might be the primary drivers of the evolution of VOC emission in euglossine-pollinated flowers.

  4. Spatial variation in pollinator-mediated selection on phenology, floral display and spur length in the orchid Gymnadenia conopsea.

    Science.gov (United States)

    Chapurlat, Elodie; Ågren, Jon; Sletvold, Nina

    2015-12-01

    Spatial variation in plant-pollinator interactions may cause variation in pollinator-mediated selection on floral traits, but to establish this link conclusively experimental studies are needed. We quantified pollinator-mediated selection on flowering phenology and morphology in four populations of the fragrant orchid Gymnadenia conopsea, and compared selection mediated by diurnal and nocturnal pollinators in two of the populations. Variation in pollinator-mediated selection explained most of the among-population variation in the strength of directional and correlational selection. Pollinators mediated correlational selection on pairs of display traits, and on one display trait and spur length, a trait affecting pollination efficiency. Only nocturnal pollinators selected for longer spurs, and mediated stronger selection on the number of flowers compared with diurnal pollinators in one population. The two types of pollinators caused correlational selection on different pairs of traits and selected for different combinations of spur length and number of flowers. The results demonstrate that spatial variation in interactions with pollinators may result in differences in directional and correlational selection on floral traits in a plant with a semi-generalized pollination system, and suggest that differences in the relative importance of diurnal and nocturnal pollinators can cause variation in selection. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

  5. Acute exposure to a sublethal dose of imidacloprid and coumaphos enhances olfactory learning and memory in the honeybee Apis mellifera.

    Science.gov (United States)

    Williamson, Sally M; Baker, Daniel D; Wright, Geraldine A

    2013-06-01

    The decline of honeybees and other pollinating insects is a current cause for concern. A major factor implicated in their decline is exposure to agricultural chemicals, in particular the neonicotinoid insecticides such as imidacloprid. Honeybees are also subjected to additional chemical exposure when beekeepers treat hives with acaricides to combat the mite Varroa destructor. Here, we assess the effects of acute sublethal doses of the neonicotinoid imidacloprid, and the organophosphate acaricide coumaphos, on honey bee learning and memory. Imidacloprid had little effect on performance in a six-trial olfactory conditioning assay, while coumaphos caused a modest impairment. We report a surprising lack of additive adverse effects when both compounds were administered simultaneously, which instead produced a modest improvement in learning and memory.

  6. 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.

  7. Honey bees are the dominant diurnal pollinator of native milkweed in a large urban park.

    Science.gov (United States)

    MacIvor, James Scott; Roberto, Adriano N; Sodhi, Darwin S; Onuferko, Thomas M; Cadotte, Marc W

    2017-10-01

    In eastern North America, the field milkweed, Asclepias syriaca L. (Asclepiadaceae), is used in planting schemes to promote biodiversity conservation for numerous insects including the endangered monarch butterfly, Danaus plexippus (Linnaeus) (Nymphalidae). Less is known about its pollinators, and especially in urban habitats where it is planted often despite being under increasing pressure from invasive plant species, such as the related milkweed, the dog-strangling vine (DSV), Vincetoxicum rossicum (Kleopow) Barbar. (Asclepiadaceae). During the A. syriaca flowering period in July 2016, we surveyed bees in open habitats along a DSV invasion gradient and inspected 433 individuals of 25 bee species in 12 genera for pollinia: these were affixed to bees that visited A. syriaca for nectar and contain pollen packets that are vectored (e.g., transferred) between flowers. Of all bees sampled, pollinia were found only on the nonindigenous honeybee, Apis mellifera (43% of all bees identified), as well as one individual bumblebee, Bombus impatiens Cresson. Pollinia were recorded from 45.2% of all honeybees collected. We found no relationship between biomass of DSV and biomass of A. syriaca per site. There was a significant positive correlation between A. syriaca biomass and the number of pollinia, and the proportion vectored. No relationship with DSV biomass was detected for the number of pollinia collected by bees but the proportion of vectored pollinia declined with increasing DSV biomass. Although we find no evidence of DSV flowers attracting potential pollinators away from A. syriaca and other flowering plants, the impacts on native plant-pollinator mutualisms relate to its ability to outcompete native plants. As wild bees do not appear to visit DSV flowers, it could be altering the landscape to one which honeybees are more tolerant than native wild bees.

  8. Multiple reversal olfactory learning in honeybees

    Directory of Open Access Journals (Sweden)

    Theo Mota

    2010-07-01

    Full Text Available In multiple reversal learning, animals trained to discriminate a reinforced from a non-reinforced stimulus are subjected to various, successive reversals of stimulus contingencies (e.g. A+ vs. B-, A- vs. B+, A+ vs. B-. This protocol is useful to determine whether or not animals learn to learn and solve successive discriminations faster (or with fewer errors with increasing reversal experience. Here we used the olfactory conditioning of proboscis extension reflex to study how honeybees Apis mellifera perform in a multiple reversal task. Our experiment contemplated four consecutive differential conditioning phases involving the same odors (A+ vs. B- to A- vs. B+ to A+ vs. B- to A- vs. B+. We show that bees in which the weight of reinforced or non-reinforced stimuli was similar mastered the multiple olfactory reversals. Bees which failed the task exhibited asymmetric responses to reinforced and non-reinforced stimuli, thus being unable to rapidly reverse stimulus contingencies. Efficient reversers did not improve their successive discriminations but rather tended to generalize their choice to both odors at the end of conditioning. As a consequence, both discrimination and reversal efficiency decreasedalong experimental phases. This result invalidates a learning-to-learn effect and indicates that bees do not only respond to the actual stimulus contingencies but rather combine these with an average of past experiences with the same stimuli.  

  9. Exposure to multiple cholinergic pesticides impairs olfactory learning and memory in honeybees.

    Science.gov (United States)

    Williamson, Sally M; Wright, Geraldine A

    2013-05-15

    Pesticides are important agricultural tools often used in combination to avoid resistance in target pest species, but there is growing concern that their widespread use contributes to the decline of pollinator populations. Pollinators perform sophisticated behaviours while foraging that require them to learn and remember floral traits associated with food, but we know relatively little about the way that combined exposure to multiple pesticides affects neural function and behaviour. The experiments reported here show that prolonged exposure to field-realistic concentrations of the neonicotinoid imidacloprid and the organophosphate acetylcholinesterase inhibitor coumaphos and their combination impairs olfactory learning and memory formation in the honeybee. Using a method for classical conditioning of proboscis extension, honeybees were trained in either a massed or spaced conditioning protocol to examine how these pesticides affected performance during learning and short- and long-term memory tasks. We found that bees exposed to imidacloprid, coumaphos, or a combination of these compounds, were less likely to express conditioned proboscis extension towards an odor associated with reward. Bees exposed to imidacloprid were less likely to form a long-term memory, whereas bees exposed to coumaphos were only less likely to respond during the short-term memory test after massed conditioning. Imidacloprid, coumaphos and a combination of the two compounds impaired the bees' ability to differentiate the conditioned odour from a novel odour during the memory test. Our results demonstrate that exposure to sublethal doses of combined cholinergic pesticides significantly impairs important behaviours involved in foraging, implying that pollinator population decline could be the result of a failure of neural function of bees exposed to pesticides in agricultural landscapes.

  10. A new hybrid bee pollinator flower pollination algorithm for solar PV parameter estimation

    International Nuclear Information System (INIS)

    Ram, J. Prasanth; Babu, T. Sudhakar; Dragicevic, Tomislav; Rajasekar, N.

    2017-01-01

    Highlights: • A new Bee Pollinator Flower Pollination Algorithm (BPFPA) is proposed for Solar PV Parameter extraction. • Standard RTC France data is used for the experimentation of BPFPA algorithm. • Four different PV modules are successfully tested via double diode model. • The BPFPA method is highly convincing in accuracy to convergence at faster rate. • The proposed BPFPA provides the best performance among the other recent techniques. - Abstract: The inaccurate I-V curve generation in solar PV modeling introduces less efficiency and on the other hand, accurate simulation of PV characteristics becomes a mandatory obligation before experimental validation. Although many optimization methods in literature have attempted to extract accurate PV parameters, all of these methods do not guarantee their convergence to the global optimum. Hence, the authors of this paper have proposed a new hybrid Bee pollinator Flower Pollination Algorithm (BPFPA) for the PV parameter extraction problem. The PV parameters for both single diode and double diode are extracted and tested under different environmental conditions. For brevity, the I_0_1, I_0_2, I_p_v for double diode and I_0_,I_p_v for single diode models are calculated analytically where the remaining parameters ‘R_s, R_p, a_1, a_2’ are optimized using BPFPA method. It is found that, the proposed Bee Pollinator method has all the scope to create exploration and exploitation in the control variable to yield a less RMSE value even under lower irradiated conditions. Further for performance validation, the parameters arrived via BPFPA method is compared with Genetic Algorithm (GA), Pattern Search (PS), Harmony Search (HS), Flower Pollination Algorithm (FPA) and Artificial Bee Swarm Optimization (ABSO). In addition, various outcomes of PV modeling and different parameters influencing the accurate PV modeling are critically analyzed.

  11. 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.

  12. On the honeybee resistance to gamma radiation

    International Nuclear Information System (INIS)

    Courtois, G.; Lecomte, J.

    1960-01-01

    The honeybee, when irradiated by gamma radiations from a cobalt-60 source can stand a 18000 r dose without any apparent harm. Noticeable harm is observed for 90000 r. while immediate death of 100% of the individuals is obtained with a 200000 r dose. The physiological condition of the honeybee plays an important role in its resistance to gamma radiation. Reprint of a paper published in Annales de l'abeille, IV, 1959, p. 285-290 [fr

  13. Lateralization of visual learning in the honeybee

    OpenAIRE

    Letzkus, Pinar; Boeddeker, Norbert; Wood, Jeff T; Zhang, Shao-Wu; Srinivasan, Mandyam V

    2007-01-01

    Lateralization is a well-described phenomenon in humans and other vertebrates and there are interesting parallels across a variety of different vertebrate species. However, there are only a few studies of lateralization in invertebrates. In a recent report, we showed lateralization of olfactory learning in the honeybee (Apis mellifera). Here, we investigate lateralization of another sensory modality, vision. By training honeybees on a modified version of a visual proboscis extension reflex ta...

  14. 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.

  15. 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.

  16. 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

  17. Pervasiveness of parasites in pollinators.

    Directory of Open Access Journals (Sweden)

    Sophie E F Evison

    Full Text Available Many pollinator populations are declining, with large economic and ecological implications. Parasites are known to be an important factor in the some of the population declines of honey bees and bumblebees, but little is known about the parasites afflicting most other pollinators, or the extent of interspecific transmission or vectoring of parasites. Here we carry out a preliminary screening of pollinators (honey bees, five species of bumblebee, three species of wasp, four species of hoverfly and three genera of other bees in the UK for parasites. We used molecular methods to screen for six honey bee viruses, Ascosphaera fungi, Microsporidia, and Wolbachia intracellular bacteria. We aimed simply to detect the presence of the parasites, encompassing vectoring as well as actual infections. Many pollinators of all types were positive for Ascosphaera fungi, while Microsporidia were rarer, being most frequently found in bumblebees. We also detected that most pollinators were positive for Wolbachia, most probably indicating infection with this intracellular symbiont, and raising the possibility that it may be an important factor in influencing host sex ratios or fitness in a diversity of pollinators. Importantly, we found that about a third of bumblebees (Bombus pascuorum and Bombus terrestris and a third of wasps (Vespula vulgaris, as well as all honey bees, were positive for deformed wing virus, but that this virus was not present in other pollinators. Deformed wing virus therefore does not appear to be a general parasite of pollinators, but does interact significantly with at least three species of bumblebee and wasp. Further work is needed to establish the identity of some of the parasites, their spatiotemporal variation, and whether they are infecting the various pollinator species or being vectored. However, these results provide a first insight into the diversity, and potential exchange, of parasites in pollinator communities.

  18. Africanized honeybees are slower learners than their European counterparts

    Science.gov (United States)

    Couvillon, Margaret J.; Degrandi-Hoffman, Gloria; Gronenberg, Wulfila

    2010-02-01

    Does cognitive ability always correlate with a positive fitness consequence? Previous research in both vertebrates and invertebrates provides mixed results. Here, we compare the learning and memory abilities of Africanized honeybees ( Apis mellifera scutellata hybrid) and European honeybees ( Apis mellifera ligustica). The range of the Africanized honeybee continues to expand, superseding the European honeybee, which led us to hypothesize that they might possess greater cognitive capabilities as revealed by a classical conditioning assay. Surprisingly, we found that fewer Africanized honeybees learn to associate an odor with a reward. Additionally, fewer Africanized honeybees remembered the association a day later. While Africanized honeybees are replacing European honeybees, our results show that they do so despite displaying a relatively poorer performance on an associative learning paradigm.

  19. 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.

  20. Pollination Requirements of Almond (Prunus dulcis): Combining Laboratory and Field Experiments.

    Science.gov (United States)

    Henselek, Yuki; Eilers, Elisabeth J; Kremen, Claire; Hendrix, Stephen D; Klein, Alexandra-Maria

    2018-03-08

    Almond (Prunus dulcis (Mill.) D. A. Webb; Rosales: Rosaceae) is a cash crop with an estimated global value of over seven billion U.S. dollars annually and commercial varieties are highly dependent on insect pollination. Therefore, the understanding of basic pollination requirements of the main varieties including pollination efficiency of honey bees (Apis mellifera, Linnaeus, Hymenoptera: Apidae) and wild pollinators is essential for almond production. We first conducted two lab experiments to examine the threshold number of pollen grains needed for successful pollination and to determine if varietal identity or diversity promotes fruit set and weight. Further, we examined stigma and ovules of flowers visited by Apis and non-Apis pollinators in the field to study the proportion of almond to non-almond pollen grains deposited, visitation time per flower visit, and tube set. Results indicate that the threshold for successful fertilization is around 60 pollen grains, but pollen can be from any compatible variety as neither pollen varietal identity nor diversity enhanced fruit set or weight. Andrena cerasifolii Cockerell (Hymenoptera: Andrenidae) was a more effective pollinator on a per single visit basis than Apis and syrphid flies. Nevertheless, Apis was more efficient than A. cerasifolii and syrphid flies as they spent less time on a flower during a single visit. Hence, planting with two compatible varieties and managing for both Apis and non-Apis pollinators is likely to be an optimal strategy for farmers to secure high and stable pollination success.

  1. Automatic behaviour analysis system for honeybees using computer vision

    DEFF Research Database (Denmark)

    Tu, Gang Jun; Hansen, Mikkel Kragh; Kryger, Per

    2016-01-01

    We present a fully automatic online video system, which is able to detect the behaviour of honeybees at the beehive entrance. Our monitoring system focuses on observing the honeybees as naturally as possible (i.e. without disturbing the honeybees). It is based on the Raspberry Pi that is a low...

  2. Pollination Reservoirs in Lowbush Blueberry (Ericales: Ericaceae)

    OpenAIRE

    Venturini, E. M.; Drummond, F. A.; Hoshide, A. K.; Dibble, A. C.; Stack, L. B.

    2017-01-01

    Abstract Pollinator-dependent agriculture heavily relies upon a single pollinator?the honey bee. To diversify pollination strategies, growers are turning to alternatives. Densely planted reservoirs of pollen- and nectar-rich flowers (pollination reservoirs, hereafter ?PRs?) may improve pollination services provided by wild bees. Our focal agroecosystem, lowbush blueberry (Vaccinium angustifolium Aiton), exists in a simple landscape uniquely positioned to benefit from PRs. First, we contrast b...

  3. 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.

  4. Concentrations of imidacloprid and thiamethoxam in pollen, nectar and leaves from seed-dressed cotton crops and their potential risk to honeybees (Apis mellifera L.).

    Science.gov (United States)

    Jiang, Jiangong; Ma, Dicheng; Zou, Nan; Yu, Xin; Zhang, Zhengqun; Liu, Feng; Mu, Wei

    2018-06-01

    Neonicotinoid insecticides (NIs) have recently been recognized as co-factors in the decline of honeybee colonies because most neonicotinoids are systemic and can transfer into the pollen and nectar of many pollinated crops. In this study, we collected pollen, nectar and leaves from a cotton crop treated with imidacloprid and thiamethoxam to measure the residue levels of these two NIs at different application doses during the flowering period. Then, the residual data were used to assess the risk posed by the systemic insecticides to honeybees following mandated methods published by the European Food Safety Authority (EFSA), and a highly toxic risk to honeybees was highlighted. Imidacloprid was found in both pollen and nectar samples, whereas thiamethoxam was found in 90% of pollen samples and over 60% of nectar samples. Analysis of the pollen and nectar revealed residual amounts of imidacloprid ranging from 1.61 to 64.58 ng g -1 in the pollen and from not detected (ND) to 1.769 ng g -1 in the nectar. By comparison, the thiamethoxam concentrations in pollen and nectar ranged from ND to 14.521 ng g -1 and from ND to 4.285 ng g -1 , respectively. The results of this study provide information on the transfer of two NIs from seed treatment to areas of the plant and provides an understanding of the potential exposure of the bee and other pollinators to systemic insecticides. Copyright © 2018 Elsevier Ltd. All rights reserved.

  5. Pollination ecology of Acacia gerrardii Benth. (Fabaceae: Mimosoideae under extremely hot-dry conditions

    Directory of Open Access Journals (Sweden)

    Abdulaziz Saad Alqarni

    2017-11-01

    Full Text Available Talh trees (Acacia gerrardii Benth. are acacias that are native to the arid and semiarid Africa and west Asia. We investigated the flowering biology, pod set and flower visitors of Talh and discussed the role of these visitors in pollen transfer. The Talh trees blossomed laterally on the nodes of one-year-old twigs. Each node produced 21 flower buds seasonally. Each flower bud opened to a flower head (FH of 60 florets. The bagged FHs podded significantly (p ⩽ 0.05 less than did the unbagged FHs. The FHs were visited by 31 insect species (25 genera, 16 families and 5 orders. The major taxa were honeybees, megachilids, butterflies, ants, beetles and thrips. Each of honeybees, megachilids and beetles showed a significant (p ⩽ 0.05 hourly pattern, while each of butterflies, ants and thrips had no hourly pattern (p > 0.05. Furthermore, some birds and mammals touched the Talh FHs. Talh trees evolved a mass flowering behavior to face pre- and post-flowering obstacles. Megachilids seemed to play the major effort of zoophily because of their relatively high numbers of individuals and species and their effective movement behavior on the FH surface. Nevertheless, honeybees and other insects and vertebrate taxa also contributed to the pollen transfer. These results greatly contribute to our understanding of the pollination ecology of acacias, especially Arabian acacias.

  6. Pollinator responses to floral colour change, nectar, and scent promote reproductive fitness in Quisqualis indica (Combretaceae).

    Science.gov (United States)

    Yan, Juan; Wang, Gang; Sui, Yi; Wang, Menglin; Zhang, Ling

    2016-04-13

    Floral colour change is visual signals for pollinators to avoid old flowers and increase pollination efficiency. Quisqualis indica flowers change colour from white to pink to red may be associated with a shift from moth to butterfly pollination. To test this hypothesis, we investigated Q. indica populations in Southwest China. Flowers secreted nectar continuously from the evening of anthesis until the following morning, then decreased gradually with floral colour change. The scent compounds in the three floral colour stages were similar; however, the scent composition was different, and the scent emission rate decreased from the white to red stage. Dichogamy in Q. indica prevents self-pollination and interference of male and female functions. Controlled pollinations demonstrated that this species is self-incompatible and needs pollinators for seed production. Different pollinators were attracted in each floral colour stage; mainly moths at night and bees and butterflies during the day. Observations of open-pollinated inflorescences showed that white flowers had a higher fruit set than pink or red flowers, indicating the high contribution of moths to reproductive success. We concluded that the nectar and scent secretion are related to floral colour change in Q. indica, in order to attract different pollinators and promote reproductive fitness.

  7. Rare royal families in honeybees, Apis mellifera

    Science.gov (United States)

    Moritz, Robin F. A.; Lattorff, H. Michael G.; Neumann, Peter; Kraus, F. Bernhard; Radloff, Sarah E.; Hepburn, H. Randall

    2005-10-01

    The queen is the dominant female in the honeybee colony, Apis mellifera, and controls reproduction. Queen larvae are selected by the workers and are fed a special diet (royal jelly), which determines caste. Because queens mate with many males a large number of subfamilies coexist in the colony. As a consequence, there is a considerable potential for conflict among the subfamilies over queen rearing. Here we show that honeybee queens are not reared at random but are preferentially reared from rare “royal” subfamilies, which have extremely low frequencies in the colony's worker force but a high frequency in the queens reared.

  8. Lateralization of visual learning in the honeybee.

    Science.gov (United States)

    Letzkus, Pinar; Boeddeker, Norbert; Wood, Jeff T; Zhang, Shao-Wu; Srinivasan, Mandyam V

    2008-02-23

    Lateralization is a well-described phenomenon in humans and other vertebrates and there are interesting parallels across a variety of different vertebrate species. However, there are only a few studies of lateralization in invertebrates. In a recent report, we showed lateralization of olfactory learning in the honeybee (Apis mellifera). Here, we investigate lateralization of another sensory modality, vision. By training honeybees on a modified version of a visual proboscis extension reflex task, we find that bees learn a colour stimulus better with their right eye.

  9. Imidacloprid intensifies its impact on honeybee and bumblebee cellular immune response when challenged with LPS (lippopolysacharide) of Escherichia coli.

    Science.gov (United States)

    Walderdorff, Louise; Laval-Gilly, Philippe; Bonnefoy, Antoine; Falla-Angel, Jaïro

    2018-05-16

    Insect hemocytes play an important role in insects' defense against environmental stressors as they are entirely dependent on their innate immune system for pathogen defense. In recent years a dramatic decline of pollinators has been reported in many countries. The drivers of this declines appear to be associated with pathogen infections like viruses, bacteria or fungi in combination with pesticide exposure. The aim of this study was thus to investigate the impact of imidacloprid, a neonicotinoid insecticide, on the cellular immune response of two pollinators (Apis mellifera and Bombus terrestris) during simultaneous immune activation with LPS (lipopolysaccharide) of Escherichia coli. For this purpose the phagocytosis capacity as well as the production of H 2 O 2 and NO of larval hemocytes, exposed to five different imidacloprid concentrations in vitro, was measured. All used pesticide concentrations showed a weakening effect on phagocytosis with but also without LPS activation. Imidacloprid decreased H 2 O 2 and increased NO production in honeybees. Immune activation by LPS clearly reinforced the effect of imidacloprid on the immune response of hemocytes in all three immune parameters tested. Bumblebee hemocytes appeared more sensitive to imidacloprid during phagocytosis assays while imidacloprid showed a greater impact on honeybee hemocytes during H 2 O 2 and NO production. Copyright © 2018 Elsevier Ltd. All rights reserved.

  10. Environmental contaminants of honeybee products in Uganda detected using LC-MS/MS and GC-ECD.

    Directory of Open Access Journals (Sweden)

    Deborah Ruth Amulen

    Full Text Available Pollinator services and the development of beekeeping as a poverty alleviating tool have gained considerable focus in recent years in sub-Saharan Africa. An improved understanding of the pervasive environmental extent of agro-chemical contaminants is critical to the success of beekeeping development and the production of clean hive products. This study developed and validated a multi-residue method for screening 36 pesticides in honeybees, honey and beeswax using LC-MS/MS and GC-ECD. Of the 36 screened pesticides, 20 were detected. The highest frequencies occurred in beeswax and in samples from apiaries located in the proximity of citrus and tobacco farms. Fungicides were the most prevalent chemical class. Detected insecticides included neonicotinoids, organophosphates, carbamates, organophosphorus, tetrazines and diacylhydrazines. All detected pesticide levels were below maximum residue limits (according to EU regulations and the lethal doses known for honeybees. However, future risk assessment is needed to determine the health effects on the African genotype of honeybees by these pesticide classes and combinations of these. In conclusion, our data present a significant challenge to the burgeoning organic honey sector in Uganda, but to achieve this, there is an urgent need to regulate the contact routes of pesticides into the beehive products. Interestingly, the "zero" detection rate of pesticides in the Mid-Northern zone is a significant indicator of the large potential to promote Ugandan organic honey for the export market.

  11. Insights into social insects from the genome of the honeybee Apis mellifera

    DEFF Research Database (Denmark)

    Hauser, Frank; Cazzamali, Giuseppe; Williamson, Michael

    2006-01-01

    Here we report the genome sequence of the honeybee Apis mellifera, a key model for social behaviour and essential to global ecology through pollination. Compared with other sequenced insect genomes, the A. mellifera genome has high A+T and CpG contents, lacks major transposon families, evolves more...... slowly, and is more similar to vertebrates for circadian rhythm, RNA interference and DNA methylation genes, among others. Furthermore, A. mellifera has fewer genes for innate immunity, detoxification enzymes, cuticle-forming proteins and gustatory receptors, more genes for odorant receptors, and novel...... genes for nectar and pollen utilization, consistent with its ecology and social organization. Compared to Drosophila, genes in early developmental pathways differ in Apis, whereas similarities exist for functions that differ markedly, such as sex determination, brain function and behaviour. Population...

  12. Interaction between Varroa destructor and imidacloprid reduces flight capacity of honeybees

    Science.gov (United States)

    Blanken, Lisa J.; van Dooremalen, Coby

    2015-01-01

    Current high losses of honeybees seriously threaten crop pollination. Whereas parasite exposure is acknowledged as an important cause of these losses, the role of insecticides is controversial. Parasites and neonicotinoid insecticides reduce homing success of foragers (e.g. by reduced orientation), but it is unknown whether they negatively affect flight capacity. We investigated how exposing colonies to the parasitic mite Varroa destructor and the neonicotinoid insecticide imidacloprid affect flight capacity of foragers. Flight distance, time and speed of foragers were measured in flight mills to assess the relative and interactive effects of high V. destructor load and a field-realistic, chronic sub-lethal dose of imidacloprid. Foragers from colonies exposed to high levels of V. destructor flew shorter distances, with a larger effect when also exposed to imidacloprid. Bee body mass partly explained our results as bees were heavier when exposed to these stressors, possibly due to an earlier onset of foraging. Our findings contribute to understanding of interacting stressors that can explain colony losses. Reduced flight capacity decreases the food-collecting ability of honeybees and may hamper the use of precocious foraging as a coping mechanism during colony (nutritional) stress. Ineffective coping mechanisms may lead to destructive cascading effects and subsequent colony collapse. PMID:26631559

  13. Blue colour preference in honeybees distracts visual attention for learning closed shapes.

    Science.gov (United States)

    Morawetz, Linde; Svoboda, Alexander; Spaethe, Johannes; Dyer, Adrian G

    2013-10-01

    Spatial vision is an important cue for how honeybees (Apis mellifera) find flowers, and previous work has suggested that spatial learning in free-flying bees is exclusively mediated by achromatic input to the green photoreceptor channel. However, some data suggested that bees may be able to use alternative channels for shape processing, and recent work shows conditioning type and training length can significantly influence bee learning and cue use. We thus tested the honeybees' ability to discriminate between two closed shapes considering either absolute or differential conditioning, and using eight stimuli differing in their spectral characteristics. Consistent with previous work, green contrast enabled reliable shape learning for both types of conditioning, but surprisingly, we found that bees trained with appetitive-aversive differential conditioning could additionally use colour and/or UV contrast to enable shape discrimination. Interestingly, we found that a high blue contrast initially interferes with bee shape learning, probably due to the bees innate preference for blue colours, but with increasing experience bees can learn a variety of spectral and/or colour cues to facilitate spatial learning. Thus, the relationship between bee pollinators and the spatial and spectral cues that they use to find rewarding flowers appears to be a more rich visual environment than previously thought.

  14. Analysis of the waggle dance motion of honeybees for the design of a biomimetic honeybee robot.

    Directory of Open Access Journals (Sweden)

    Tim Landgraf

    Full Text Available The honeybee dance "language" is one of the most popular examples of information transfer in the animal world. Today, more than 60 years after its discovery it still remains unknown how follower bees decode the information contained in the dance. In order to build a robotic honeybee that allows a deeper investigation of the communication process we have recorded hundreds of videos of waggle dances. In this paper we analyze the statistics of visually captured high-precision dance trajectories of European honeybees (Apis mellifera carnica. The trajectories were produced using a novel automatic tracking system and represent the most detailed honeybee dance motion information available. Although honeybee dances seem very variable, some properties turned out to be invariant. We use these properties as a minimal set of parameters that enables us to model the honeybee dance motion. We provide a detailed statistical description of various dance properties that have not been characterized before and discuss the role of particular dance components in the commmunication process.

  15. Pyrethroids and Nectar Toxins Have Subtle Effects on the Motor Function, Grooming and Wing Fanning Behaviour of Honeybees (Apis mellifera).

    Science.gov (United States)

    Oliver, Caitlin J; Softley, Samantha; Williamson, Sally M; Stevenson, Philip C; Wright, Geraldine A

    2015-01-01

    Sodium channels, found ubiquitously in animal muscle cells and neurons, are one of the main target sites of many naturally-occurring, insecticidal plant compounds and agricultural pesticides. Pyrethroids, derived from compounds found only in the Asteraceae, are particularly toxic to insects and have been successfully used as pesticides including on flowering crops that are visited by pollinators. Pyrethrins, from which they were derived, occur naturally in the nectar of some flowering plant species. We know relatively little about how such compounds--i.e., compounds that target sodium channels--influence pollinators at low or sub-lethal doses. Here, we exposed individual adult forager honeybees to several compounds that bind to sodium channels to identify whether these compounds affect motor function. Using an assay previously developed to identify the effect of drugs and toxins on individual bees, we investigated how acute exposure to 10 ng doses (1 ppm) of the pyrethroid insecticides (cyfluthrin, tau-fluvalinate, allethrin and permethrin) and the nectar toxins (aconitine and grayanotoxin I) affected honeybee locomotion, grooming and wing fanning behaviour. Bees exposed to these compounds spent more time upside down and fanning their wings. They also had longer bouts of standing still. Bees exposed to the nectar toxin, aconitine, and the pyrethroid, allethrin, also spent less time grooming their antennae. We also found that the concentration of the nectar toxin, grayanotoxin I (GTX), fed to bees affected the time spent upside down (i.e., failure to perform the righting reflex). Our data show that low doses of pyrethroids and other nectar toxins that target sodium channels mainly influence motor function through their effect on the righting reflex of adult worker honeybees.

  16. Do honeybees, Apis mellifera scutellata, regulate humidity in their nest?

    Science.gov (United States)

    Human, Hannelie; Nicolson, Sue W.; Dietemann, Vincent

    2006-08-01

    Honeybees are highly efficient at regulating the biophysical parameters of their hive according to colony needs. Thermoregulation has been the most extensively studied aspect of nest homeostasis. In contrast, little is known about how humidity is regulated in beehives, if at all. Although high humidity is necessary for brood development, regulation of this parameter by honeybee workers has not yet been demonstrated. In the past, humidity was measured too crudely for a regulation mechanism to be identified. We reassess this issue, using miniaturised data loggers that allow humidity measurements in natural situations and at several places in the nest. We present evidence that workers influence humidity in the hive. However, there are constraints on potential regulation mechanisms because humidity optima may vary in different locations of the nest. Humidity could also depend on variable external factors, such as water availability, which further impair the regulation. Moreover, there are trade-offs with the regulation of temperature and respiratory gas exchanges that can disrupt the establishment of optimal humidity levels. As a result, we argue that workers can only adjust humidity within sub-optimal limits.

  17. Serial position learning in honeybees.

    Directory of Open Access Journals (Sweden)

    Randolf Menzel

    Full Text Available Learning of stimulus sequences is considered as a characteristic feature of episodic memory since it contains not only a particular item but also the experience of preceding and following events. In sensorimotor tasks resembling navigational performance, the serial order of objects is intimately connected with spatial order. Mammals and birds develop episodic(-like memory in serial spatio-temporal tasks, and the honeybee learns spatio-temporal order when navigating between the nest and a food source. Here I examine the structure of the bees' memory for a combined spatio-temporal task. I ask whether discrimination and generalization are based solely on simple forms of stimulus-reward learning or whether they require sequential configurations. Animals were trained to fly either left or right in a continuous T-maze. The correct choice was signaled by the sequence of colors (blue, yellow at four positions in the access arm. If only one of the possible 4 signals is shown (either blue or yellow, the rank order of position salience is 1, 2 and 3 (numbered from T-junction. No learning is found if the signal appears at position 4. If two signals are shown, differences at positions 1 and 2 are learned best, those at position 3 at a low level, and those at position 4 not at all. If three or more signals are shown these results are corroborated. This salience rank order again appeared in transfer tests, but additional configural phenomena emerged. Most of the results can be explained with a simple model based on the assumption that the four positions are equipped with different salience scores and that these add up independently. However, deviations from the model are interpreted by assuming stimulus configuration of sequential patterns. It is concluded that, under the conditions chosen, bees rely most strongly on memories developed during simple forms of associative reward learning, but memories of configural serial patterns contribute, too.

  18. 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)

  19. Side-Specific Reward Memories in Honeybees

    Science.gov (United States)

    Gil, Mariana; Menzel, Randolf; De Marco, Rodrigo J.

    2009-01-01

    We report a hitherto unknown form of side-specific learning in honeybees. We trained bees individually by coupling gustatory and mechanical stimulation of each antenna with either increasing or decreasing volumes of sucrose solution offered to the animal's proboscis along successive learning trials. Next, we examined their proboscis extension…

  20. Neuroscience: Intelligence in the Honeybee Mushroom Body

    OpenAIRE

    Caron, Sophie; Abbott, Larry F.

    2017-01-01

    Intelligence, in most people’s conception, involves combining pieces of evidence to reach non-obvious conclusions. A recent theoretical study shows that intelligence-like brain functions can emerge from simple neural circuits, in this case the honeybee mushroom body.

  1. Honeybees, Butterflies, and Ladybugs: Partners to Plants

    Science.gov (United States)

    Campbell, Ashley

    2009-01-01

    Honeybees, butterflies, and ladybugs all have fascinating mutually beneficial relationships with plants and play important ecosystem roles. Children also love these creatures. But how do we teach children about these symbiotic interactions and help them appreciate their vital roles in our environment? One must is to give children direct experience…

  2. Pollination and floral biology of Adonis vernalis L. (Ranunculaceae – a case study of threatened species

    Directory of Open Access Journals (Sweden)

    Bożena Denisow

    2014-02-01

    Full Text Available Although the knowledge of pollination systems of rare and threatened species is one of the principles for development of optimal conservation and management strategies, the data about their pollination requirements are scarce or incomplete. Different problems are listed (xerothermic habitat disappearance, overgrowing of patches, plant biology i.e., slow plant growth, problems with seed germination among the possible causes of Adonis vernalis being threatened, but until now no consideration was given to the flowering biology and pollination. The observations of flowering biology of A. vernalis (Ranunculaceae, a clonal species, were conducted in an out-of-compact-range population, in the Lublin Upland, Poland (51°18'55" N, 22°38'21" E, in 2011–2013. The reproductive potential of A. vernalis is related to the population age structure, pollination syndrome, and breeding system. The flowers exhibit incomplete protogyny. The dichogamy function is supported by different (biological, morphological mechanisms. Stigma receptivity occurred about one day before anthers started shedding self-pollen, and pollen viability was increasing gradually during the flower life-span (66.3% in distal anthers vs. 77.3% in proximal. The decrease in pollen production and in pollen viability coincided with the lowest degree of seed set, irrespective of the pollination treatment. Pollen vectors are necessary for efficient pollination, as the proportion of pistils setting fruits after open pollination (41–82.1% was significantly higher compared to spontaneous self-pollination (only 5.5–12.3%. The pollination requirements together with pollen/ovule ratio (P/O = 501 indicate a facultative xenogamous breeding system in A. vernalis. Therefore, in the conditions of the global lack of pollinators, improper pollination may weaken the population by leading to a decrease in the proportion of recombinants, and in addition to other factors, may accelerate extinction of small A

  3. Molecular, pharmacological, and signaling properties of octopamine receptors from honeybee (Apis mellifera) brain.

    Science.gov (United States)

    Balfanz, Sabine; Jordan, Nadine; Langenstück, Teresa; Breuer, Johanna; Bergmeier, Vera; Baumann, Arnd

    2014-04-01

    G protein-coupled receptors are important regulators of cellular signaling processes. Within the large family of rhodopsin-like receptors, those binding to biogenic amines form a discrete subgroup. Activation of biogenic amine receptors leads to transient changes of intracellular Ca²⁺-([Ca²⁺](i)) or 3',5'-cyclic adenosine monophosphate ([cAMP](i)) concentrations. Both second messengers modulate cellular signaling processes and thereby contribute to long-lasting behavioral effects in an organism. In vivo pharmacology has helped to reveal the functional effects of different biogenic amines in honeybees. The phenolamine octopamine is an important modulator of behavior. Binding of octopamine to its receptors causes elevation of [Ca²⁺](i) or [cAMP](i). To date, only one honeybee octopamine receptor that induces Ca²⁺ signals has been molecularly and pharmacologically characterized. Here, we examined the pharmacological properties of four additional honeybee octopamine receptors. When heterologously expressed, all receptors induced cAMP production after binding to octopamine with EC₅₀(s) in the nanomolar range. Receptor activity was most efficiently blocked by mianserin, a substance with antidepressant activity in vertebrates. The rank order of inhibitory potency for potential receptor antagonists was very similar on all four honeybee receptors with mianserin > cyproheptadine > metoclopramide > chlorpromazine > phentolamine. The subroot of octopamine receptors activating adenylyl cyclases is the largest that has so far been characterized in arthropods, and it should now be possible to unravel the contribution of individual receptors to the physiology and behavior of honeybees. © 2013 International Society for Neurochemistry.

  4. Enhancing Legume Ecosystem Services through an Understanding of Plant–Pollinator Interplay

    Science.gov (United States)

    Suso, María J.; Bebeli, Penelope J.; Christmann, Stefanie; Mateus, Célia; Negri, Valeria; Pinheiro de Carvalho, Miguel A. A.; Torricelli, Renzo; Veloso, Maria M.

    2016-01-01

    Legumes are bee-pollinated, but to a different extent. The importance of the plant–pollinator interplay (PPI), in flowering crops such as legumes lies in a combination of the importance of pollination for the production service and breeding strategies, plus the increasing urgency in mitigating the decline of pollinators through the development and implementation of conservation measures. To realize the full potential of the PPI, a multidisciplinary approach is required. This article assembles an international team of genebank managers, geneticists, plant breeders, experts on environmental governance and agro-ecology, and comprises several sections. The contributions in these sections outline both the state of the art of knowledge in the field and the novel aspects under development, and encompass a range of reviews, opinions and perspectives. The first three sections explore the role of PPI in legume breeding strategies. PPI based approaches to crop improvement can make it possible to adapt and re-design breeding strategies to meet both goals of: (1) optimal productivity, based on an efficient use of pollinators, and (2) biodiversity conservation. The next section deals with entomological aspects and focuses on the protection of the “pest control service” and pollinators in legume crops. The final section addresses general approaches to encourage the synergy between food production and pollination services at farmer field level. Two basic approaches are proposed: (a) Farming with Alternative Pollinators and (b) Crop Design System. PMID:27047514

  5. Enhancing legume ecosystem services through an understanding of plant-pollinator interplay

    Directory of Open Access Journals (Sweden)

    Maria Jose eSuso

    2016-03-01

    Full Text Available Legumes are bee-pollinated, but to a different extent. The importance of the plant-pollinator interplay (PPI, in flowering crops such as legumes lies in a combination of the importance of pollination for the production service and breeding strategies, plus the increasing urgency in mitigating the decline of pollinators through the development and implementation of conservation measures. To realize the full potential of the PPI, a multidisciplinary approach is required. This article assembles an international team of genebank managers, geneticists, plant breeders, experts on environmental governance and agro-ecology, and comprises several sections. The contributions in these sections outline both the state of the art of knowledge in the field and the novel aspects under development, and encompass a range of reviews, opinions and perspectives. The first three sections explore the role of PPI in legume breeding strategies. PPI based approaches to crop improvement can make it possible to adapt and re-design breeding strategies to meet both goals of: 1 optimal productivity, based on an efficient use of pollinators, and 2 biodiversity conservation. The next section deals with entomological aspects and focuses on the protection of the pest control service and pollinators in legume crops. The final section addresses general approaches to encourage the synergy between food production and pollination services at farmer field level. Two basic approaches are proposed: a Farming with Alternative Pollinators (FAP and b Crop Design System (CDS.

  6. How do honeybees use their magnetic compass? Can they see the North?

    Science.gov (United States)

    Válková, T; Vácha, M

    2012-08-01

    fitness of this dominant pollinator might be affected by RF fields. The goal of this review is to provide an overview of the path that the behavioral research on honeybee magnetoreception has taken and to discuss it in the context of contemporary data obtained on other insects.

  7. Molecular Mechanisms Underlying Formation of Long-Term Reward Memories and Extinction Memories in the Honeybee ("Apis Mellifera")

    Science.gov (United States)

    Eisenhardt, Dorothea

    2014-01-01

    The honeybee ("Apis mellifera") has long served as an invertebrate model organism for reward learning and memory research. Its capacity for learning and memory formation is rooted in the ecological need to efficiently collect nectar and pollen during summer to ensure survival of the hive during winter. Foraging bees learn to associate a…

  8. Detection of Methyl Salicylate Transforted by Honeybees (Apis mellifera) Using Solid Phase Microextration (SPME) Fibers; TOPICAL

    International Nuclear Information System (INIS)

    BENDER, SUSAN FAE ANN; RODACY, PHILIP J.; BARNETT, JAMES L.; BENDER, GARY L.

    2001-01-01

    The ultimate goal of many environmental measurements is to determine the risk posed to humans or ecosystems by various contaminants. Conventional environmental monitoring typically requires extensive sampling grids covering several media including air, water, soil and vegetation. A far more efficient, innovative and inexpensive tactic has been found using honeybees as sampling mechanisms. Members from a single bee colony forage over large areas ((approx)2 x 10(sup 6) m(sup 2)), making tens of thousands of trips per day, and return to a fixed location where sampling can be conveniently conducted. The bees are in direct contact with the air, water, soil and vegetation where they encounter and collect any contaminants that are present in gaseous, liquid and particulate form. The monitoring of honeybees when they return to the hive provides a rapid method to assess chemical distributions and impacts (1). The primary goal of this technology is to evaluate the efficiency of the transport mechanism (honeybees) to the hive using preconcentrators to collect samples. Once the extent and nature of the contaminant exposure has been characterized, resources can be distributed and environmental monitoring designs efficiently directed to the most appropriate locations. Methyl salicylate, a chemical agent surrogate was used as the target compound in this study

  9. Detection of Methyl Salicylate Transforted by Honeybees (Apis mellifera) Using Solid Phase Microextration (SPME) Fibers

    Energy Technology Data Exchange (ETDEWEB)

    BENDER, SUSAN FAE ANN; RODACY, PHILIP J.; BARNETT, JAMES L.; BENDER, GARY L.

    2001-12-01

    The ultimate goal of many environmental measurements is to determine the risk posed to humans or ecosystems by various contaminants. Conventional environmental monitoring typically requires extensive sampling grids covering several media including air, water, soil and vegetation. A far more efficient, innovative and inexpensive tactic has been found using honeybees as sampling mechanisms. Members from a single bee colony forage over large areas ({approx}2 x 10{sup 6} m{sup 2}), making tens of thousands of trips per day, and return to a fixed location where sampling can be conveniently conducted. The bees are in direct contact with the air, water, soil and vegetation where they encounter and collect any contaminants that are present in gaseous, liquid and particulate form. The monitoring of honeybees when they return to the hive provides a rapid method to assess chemical distributions and impacts (1). The primary goal of this technology is to evaluate the efficiency of the transport mechanism (honeybees) to the hive using preconcentrators to collect samples. Once the extent and nature of the contaminant exposure has been characterized, resources can be distributed and environmental monitoring designs efficiently directed to the most appropriate locations. Methyl salicylate, a chemical agent surrogate was used as the target compound in this study.

  10. Queen promiscuity lowers disease within honeybee colonies

    Science.gov (United States)

    Seeley, Thomas D; Tarpy, David R

    2006-01-01

    Most species of social insects have singly mated queens, but in some species each queen mates with numerous males to create a colony with a genetically diverse worker force. The adaptive significance of polyandry by social insect queens remains an evolutionary puzzle. Using the honeybee (Apis mellifera), we tested the hypothesis that polyandry improves a colony's resistance to disease. We established colonies headed by queens that had been artificially inseminated by either one or 10 drones. Later, we inoculated these colonies with spores of Paenibacillus larvae, the bacterium that causes a highly virulent disease of honeybee larvae (American foulbrood). We found that, on average, colonies headed by multiple-drone inseminated queens had markedly lower disease intensity and higher colony strength at the end of the summer relative to colonies headed by single-drone inseminated queens. These findings support the hypothesis that polyandry by social insect queens is an adaptation to counter disease within their colonies. PMID:17015336

  11. Hybrid origins of Australian honeybees (Apis mellifera)

    OpenAIRE

    Chapman , Nadine C.; Harpur , Brock A.; Lim , Julianne; Rinderer , Thomas E.; Allsopp , Michael H.; Zayed , Amro; Oldroyd , Benjamin P.

    2016-01-01

    International audience; Abstract With increased globalisation and homogenisation, the maintenance of genetic integrity in local populations of agriculturally important species is of increasing concern. The western honeybee (Apis mellifera) provides an interesting perspective as it is both managed and wild, with a large native range and much larger introduced range. We employed a newly created 95 single nucleotide polymorphism (SNP) test to characterise the genetic ancestry of the Australian c...

  12. Queen promiscuity lowers disease within honeybee colonies

    OpenAIRE

    Seeley, Thomas D; Tarpy, David R

    2006-01-01

    Most species of social insects have singly mated queens, but in some species each queen mates with numerous males to create a colony with a genetically diverse worker force. The adaptive significance of polyandry by social insect queens remains an evolutionary puzzle. Using the honeybee (Apis mellifera), we tested the hypothesis that polyandry improves a colony's resistance to disease. We established colonies headed by queens that had been artificially inseminated by either one or 10 drones. ...

  13. The importance of bee pollination of the sour cherry (Prunus cerasus Cultivar ‘Stevnsbaer’ in Denmark

    Directory of Open Access Journals (Sweden)

    Lise Hansted

    2012-12-01

    Full Text Available Low fruit set, despite normally-developed flowers, is often a significant contributor to poor yield of the self-fertile sour cherry (Prunus cerasus cultivar ‘Stevnsbaer’ in Denmark. The aim of this study was to investigate the effect of insect, and particularly, bee pollination on the fruit set of this cultivar, in order to provide orchard management information for both Danish ‘Stevnsbaer’ growers and beekeepers. Visits to cherry flowers by honey bees (Apis mellifera, Bombus species and solitary bees, were recorded during the flowering of ‘Stevnsbaer’ in five separate Danish orchards. The results indicate that there is a significantly higher fruit set on open pollinated branches when compared to caged branches, where bees and other pollinating insects where excluded. The results were qualitatively consistent over three different seasons (2007, 2009 and 2010. A period of prolonged cold, humid weather before and during early flowering probably reduced fruit set significantly in 2010 compared to 2009. Regarding the apparent benefits of bee pollination on fruit set and subsequent implications for yield, we recommend placing honeybees in ‘Stevnsbaer’ orchards during flowering to sustain commercially viable production. Another valuable management strategy would be to improve foraging and nesting conditions to support both honey and wild bees in and around the orchards.

  14. Collective fluid mechanics of honeybee nest ventilation

    Science.gov (United States)

    Gravish, Nick; Combes, Stacey; Wood, Robert J.; Peters, Jacob

    2014-11-01

    Honeybees thermoregulate their brood in the warm summer months by collectively fanning their wings and creating air flow through the nest. During nest ventilation workers flap their wings in close proximity in which wings continuously operate in unsteady oncoming flows (i.e. the wake of neighboring worker bees) and near the ground. The fluid mechanics of this collective aerodynamic phenomena are unstudied and may play an important role in the physiology of colony life. We have performed field and laboratory observations of the nest ventilation wing kinematics and air flow generated by individuals and groups of honeybee workers. Inspired from these field observations we describe here a robotic model system to study collective flapping wing aerodynamics. We microfabricate arrays of 1.4 cm long flapping wings and observe the air flow generated by arrays of two or more fanning robotic wings. We vary phase, frequency, and separation distance among wings and find that net output flow is enhanced when wings operate at the appropriate phase-distance relationship to catch shed vortices from neighboring wings. These results suggest that by varying position within the fanning array honeybee workers may benefit from collective aerodynamic interactions during nest ventilation.

  15. Cooperative random Levy flight searches and the flight patterns of honeybees

    International Nuclear Information System (INIS)

    Reynolds, A.M.

    2006-01-01

    The most efficient Levy flight (scale-free) searching strategy for N independent searchers to adopt when target sites are randomly and sparsely distributed is identified. For N=1, it is well known that the optimal searching strategy is attained when μ=2, where the exponent μ characterizes the Levy distribution, P(l)=l -μ , of flight-lengths. For N>1, the optimal searching strategy is attained as μ->1. It is suggested that the orientation flights of honeybees can be understood within the context of such an optimal cooperative random Levy flight searching strategy. Upon returning to their hive after surveying a landscape honeybees can exchange information about the locations of target sites through the waggle dance. In accordance with observations it is predicted that the waggle dance can be disrupted without noticeable influence on a hive's ability to maintain weight when forage is plentiful

  16. Protein pattern of the honeybee venoms of Egypt | Zalat | Egyptian ...

    African Journals Online (AJOL)

    The venom composition of the Egyptian honeybee Apis mellifera lamarckii, the Carniolan honeybee Apis mellifera carnica and a hybrid with unknown origin were analyzed using electrophoresis (SDS-PAGE). All venoms shared six bands with molecular weights of 97.400, 67.400, 49.000, 45.000, 43.000 and 14.000D.

  17. Infections of Nosema ceranae in four different honeybee species.

    Science.gov (United States)

    Chaimanee, Veeranan; Warrit, Natapot; Chantawannakul, Panuwan

    2010-10-01

    The microsporidium Nosema ceranae is detected in honeybees in Thailand for the first time. This endoparasite has recently been reported to infect most Apis mellifera honeybee colonies in Europe, the US, and parts of Asia, and is suspected to have displaced the endemic endoparasite species, Nosema apis, from the western A. mellifera. We collected and identified species of microsporidia from the European honeybee (A. mellifera), the cavity nesting Asian honeybee (Apis cerana), the dwarf Asian honeybee (Apis florea) and the giant Asian honeybee (Apis dorsata) from colonies in Northern Thailand. We used multiplex PCR technique with two pairs of primers to differentiate N. ceranae from N. apis. From 80 A. mellifera samples, 62 (77.5%) were positively identified for the presence of the N. ceranae. Amongst 46 feral colonies of Asian honeybees (A. cerana, A. florea and A. dorsata) examined for Nosema infections, only N. ceranae could be detected. No N. apis was found in our samples. N. ceranae is found to be the only microsporidium infesting honeybees in Thailand. Moreover, we found the frequencies of N. ceranae infection in native bees to be less than that of A. mellifera. Copyright 2010 Elsevier Inc. All rights reserved.

  18. A review of African honeybees, behaviour and potential for ...

    African Journals Online (AJOL)

    African honeybees have a higher tendency to swarm, abscond and migrate than their counterparts in Europe and elsewhere, thus making it more difficult to maintain African honeybee colonies over years. They are also labeled as overly defensive, with a high propensity to sting, making their management a challenge.

  19. Honeybee forage, bee visitation counts and the properties of honey ...

    African Journals Online (AJOL)

    The aim of the survey was to document honeybee forage plants and asses honeybee visitation counts on different forage plants and properties of honey from selected agro-ecological zones of Uganda. In order to achieve the objectives of the study, a survey of the apiaries and beekeepers was done by selecting fifteen bee ...

  20. Genetic diversity and population structure of Chinese honeybees ...

    African Journals Online (AJOL)

    Genetic diversity and population structure of Chinese honeybees (Apis cerana) under microsatellite markers. T Ji, L Yin, G Chen. Abstract. Using 21 microsatellite markers and PCR method, the polymorphisms of 20 Apis cerana honeybee populations across China was investigated and the genetic structure and diversity of ...

  1. Modelling the subgenual organ of the honeybee, Apis mellifera

    DEFF Research Database (Denmark)

    Storm, Jesper; Kilpinen, Ole

    1998-01-01

    In a recent study on the honeybee (Apis mellifera), the subgenual organ was observed moving inside the leg during sinusoidal vibrations of the leg (Kilpinen and Storm 1997). The subgenual organ of the honeybee is suspended in a haemolymph channel in the tibia of each leg. When the leg accelerates...

  2. Pollinator-independent orchid attracts biotic pollinators due the production of lipoidal substances.

    Science.gov (United States)

    Pansarin, E R; Bergamo, P J; Ferreira-Caliman, M J

    2018-03-01

    Flowering plants often depend on the attraction of biotic pollinators for sexual reproduction. Consequently, the emergence and maintenance of selected floral attributes related to pollinator attraction and rewarding are driven by pollinator pressure. In this paper we explore the effect of pollinators, rainfall, temperature and air humidity on the reproduction of a Brazilian terrestrial orchid, Cranichis candida based on data of phenology, flower resources, olfactory and visual attraction cues, pollinators and breeding system. The flowers of C. candida are strongly protandrous and pollinated by workers of the social native bee Tetragonisca angustula. The bees collect labellar lipoidal substances (wax scales), which are transported to the nest. The lipoidal substance is composed of sterols, hydrocarbons and terpenes. The last presumably protects the bees and their nests against pathogens and other arthropods. C. candida sets fruits through biotic self- and cross-pollination, and spontaneously due the action of raindrops on flowers. Our results indicate that in C. candida, although rain-mediated spontaneous self-pollination happens, fructification mediated by biotic pollinations also occurs, which may result in fruit set by cross-pollination. A mixed pollination system must result in higher genetic variability when compared to species whose fruits are produced entirely by self-pollination. On the other hand, autogamy is a form of reproductive assurance, and has commonly evolved where pollination services are rare or absent. © 2017 German Society for Plant Sciences and The Royal Botanical Society of the Netherlands.

  3. Why so many flowers? A preliminary assessment of mixed pollination strategy enhancing sexual reproduction of the invasive Acacia longifolia in Portugal

    Directory of Open Access Journals (Sweden)

    M. Giovanetti

    2018-03-01

    Full Text Available Acacia longifolia, a native legume from Australia, has been introduced in many European countries and elsewhere, thus becoming one of the most important global invasive species. In Europe, its flowering occurs in a period unsuitable for insect activity: nonetheless it is considered entomophilous. Floral traits of this species are puzzling: brightly coloured and scented as liked by insects, but with abundant staminate small-sized flowers and relatively small pollen grains, as it is common in anemophilous species. Invasion processes are especially favoured when reshaping local ecological networks, thus the interest in understanding pollination syndromes associated with invasive plant species that may facilitate invasiveness. Moreover, a striking difference exists between its massive flowering and relatively poor seed set. We introduced a novel approach: first, we consider the possibility that a part of the pollination success is carried on by wind and, second, we weighted the ethological perspective of the main pollinator. During the flowering season of A. longifolia (February–April 2016, we carried on exclusion experiments to detect the relative contribution of insects and wind. While the exclusion experiments corroborated the need for pollen vectors, we actually recorded a low abundance of insects. The honeybee, known pollinator of acacias, was relatively rare and not always productive in terms of successful visits. While wind contributed to seed set, focal observations confirmed that honeybees transfer pollen when visiting both the inflorescences to collect pollen and the extrafloral nectaries to collect nectar. The mixed pollination strategy of A. longifolia may then be the basis of its success in invading Portugal's windy coasts.

  4. Seminal fluid of honeybees contains multiple mechanisms to combat infections of the sexually transmitted pathogen Nosema apis.

    Science.gov (United States)

    Peng, Yan; Grassl, Julia; Millar, A Harvey; Baer, Boris

    2016-01-27

    The societies of ants, bees and wasps are genetically closed systems where queens only mate during a brief mating episode prior to their eusocial life and males therefore provide queens with a lifetime supply of high-quality sperm. These ejaculates also contain a number of defence proteins that have been detected in the seminal fluid but their function and efficiency have never been investigated in great detail. Here, we used the honeybee Apis mellifera and quantified whether seminal fluid is able to combat infections of the fungal pathogen Nosema apis, a widespread honeybee parasite that is also sexually transmitted. We provide the first empirical evidence that seminal fluid has a remarkable antimicrobial activity against N. apis spores and that antimicrobial seminal fluid components kill spores in multiple ways. The protein fraction of seminal fluid induces extracellular spore germination, which disrupts the life cycle of N. apis, whereas the non-protein fraction of seminal fluid induces a direct viability loss of intact spores. We conclude that males provide their ejaculates with efficient antimicrobial molecules that are able to kill N. apis spores and thereby reduce the risk of disease transmission during mating. Our findings could be of broader significance to master honeybee diseases in managed honeybee stock in the future. © 2016 The Author(s).

  5. Diversity of sunflower pollinators and their effect on seed yield in Makueni District, Eastern Kenya

    OpenAIRE

    Nderitu, J.; Nyamasyo, G.; Kasina, M.; Oronje, M. L.

    2008-01-01

    A field experiment was carried out in 2004 and 2005 to identify the diversity of sunflower (Helianthus annuus L.) pollinators and their influence on seed yield in Makueni district, a semi-arid area in Eastern Kenya. Insect flower visitors were recorded, pollen counted from their body and pollination efficiency index for each visitor determined. Seed yield from plots where insect visitors had access to and where they were denied access was compared. The proportional difference of yield from th...

  6. A Locomotor Deficit Induced by Sublethal Doses of Pyrethroid and Neonicotinoid Insecticides in the Honeybee Apis mellifera.

    Science.gov (United States)

    Charreton, Mercédès; Decourtye, Axel; Henry, Mickaël; Rodet, Guy; Sandoz, Jean-Christophe; Charnet, Pierre; Collet, Claude

    2015-01-01

    The toxicity of pesticides used in agriculture towards non-targeted organisms and especially pollinators has recently drawn the attention from a broad scientific community. Increased honeybee mortality observed worldwide certainly contributes to this interest. The potential role of several neurotoxic insecticides in triggering or potentiating honeybee mortality was considered, in particular phenylpyrazoles and neonicotinoids, given that they are widely used and highly toxic for insects. Along with their ability to kill insects at lethal doses, they can compromise survival at sublethal doses by producing subtle deleterious effects. In this study, we compared the bee's locomotor ability, which is crucial for many tasks within the hive (e.g. cleaning brood cells, feeding larvae…), before and after an acute sublethal exposure to one insecticide belonging to the two insecticide classes, fipronil and thiamethoxam. Additionally, we examined the locomotor ability after exposure to pyrethroids, an older chemical insecticide class still widely used and known to be highly toxic to bees as well. Our study focused on young bees (day 1 after emergence) since (i) few studies are available on locomotion at this stage and (ii) in recent years, pesticides have been reported to accumulate in different hive matrices, where young bees undergo their early development. At sublethal doses (SLD48h, i.e. causing no mortality at 48 h), three pyrethroids, namely cypermethrin (2.5 ng/bee), tetramethrin (70 ng/bee), tau-fluvalinate (33 ng/bee) and the neonicotinoid thiamethoxam (3.8 ng/bee) caused a locomotor deficit in honeybees. While the SLD48h of fipronil (a phenylpyrazole, 0.5 ng/bee) had no measurable effect on locomotion, we observed high mortality several days after exposure, an effect that was not observed with the other insecticides. Although locomotor deficits observed in the sublethal range of pyrethroids and thiamethoxam would suggest deleterious effects in the field, the case of

  7. A Locomotor Deficit Induced by Sublethal Doses of Pyrethroid and Neonicotinoid Insecticides in the Honeybee Apis mellifera.

    Directory of Open Access Journals (Sweden)

    Mercédès Charreton

    Full Text Available The toxicity of pesticides used in agriculture towards non-targeted organisms and especially pollinators has recently drawn the attention from a broad scientific community. Increased honeybee mortality observed worldwide certainly contributes to this interest. The potential role of several neurotoxic insecticides in triggering or potentiating honeybee mortality was considered, in particular phenylpyrazoles and neonicotinoids, given that they are widely used and highly toxic for insects. Along with their ability to kill insects at lethal doses, they can compromise survival at sublethal doses by producing subtle deleterious effects. In this study, we compared the bee's locomotor ability, which is crucial for many tasks within the hive (e.g. cleaning brood cells, feeding larvae…, before and after an acute sublethal exposure to one insecticide belonging to the two insecticide classes, fipronil and thiamethoxam. Additionally, we examined the locomotor ability after exposure to pyrethroids, an older chemical insecticide class still widely used and known to be highly toxic to bees as well. Our study focused on young bees (day 1 after emergence since (i few studies are available on locomotion at this stage and (ii in recent years, pesticides have been reported to accumulate in different hive matrices, where young bees undergo their early development. At sublethal doses (SLD48h, i.e. causing no mortality at 48 h, three pyrethroids, namely cypermethrin (2.5 ng/bee, tetramethrin (70 ng/bee, tau-fluvalinate (33 ng/bee and the neonicotinoid thiamethoxam (3.8 ng/bee caused a locomotor deficit in honeybees. While the SLD48h of fipronil (a phenylpyrazole, 0.5 ng/bee had no measurable effect on locomotion, we observed high mortality several days after exposure, an effect that was not observed with the other insecticides. Although locomotor deficits observed in the sublethal range of pyrethroids and thiamethoxam would suggest deleterious effects in the field

  8. Morphofunctional Traits and Pollination Mechanisms of Coronilla emerus L. Flowers (Fabaceae)

    Science.gov (United States)

    Aronne, Giovanna; Giovanetti, Manuela; De Micco, Veronica

    2012-01-01

    It is accepted that the papilionaceous corolla of the Fabaceae evolved under the selective pressure of bee pollinators. Morphology and function of different parts of Coronilla emerus L. flowers were related to their role in the pollination mechanism. The corolla has a vexillum with red nectar lines, a keel hiding stamens and pistil, and two wing petals fasten to the keel with two notched folds. Pollinators land on the complex of keel and wings, trigger the protrusion of pollen and finally of the stigma from the keel tip. Data on pollen viability and stigma receptivity prove that flowers are proterandrous. The results of hand-pollination experiments confirmed that insects are fundamental to set seed. Interaction with pollinators allows not only the transport of pollen but also the rupture of the stigmatic cuticle, necessary to achieve both allogamy and autogamy. Field observations showed that Hymenoptera, Lepidoptera, and Diptera visited the flowers. Only some of the Hymenoptera landed on the flowers from the front and elicited pollination mechanisms. Most of the insects sucked the nectar from the back without any pollen transfer. Finally, morphological and functional characteristics of C. emerus flowers are discussed in terms of floral larceny and reduction in pollination efficiency. PMID:22666114

  9. Effects of altitudinal variation on pollination in purple passion fruit crops (passiflora edulis f. edulis)

    International Nuclear Information System (INIS)

    Medina Gutierrez, Julian; Ospina Torres, Rodulfo; Nates Parra, Guiomar

    2012-01-01

    The purpose of this paper is to study in two crops of purple passion fruit Passiflora edulis f. edulis harvested at different altitudes (2225 m.a.s.l. and 1657 m.a.s.l.) in the municipality of Buenavista - Boyaca, located in the eastern Mountain range of Colombia, in order to familiarize with visitors and pollinators. This study reveals that in both crops there were differences found in composition, the number of visitors and pollinators. In the crop at 2225 m.a.s.l., 7 species were registered, while 18 species were recorded at the 1657 m.a.s.l. crop. In order to achieve this, collected material by the visitors and the floral structures with which they approach, were observed; at the same time four experiments took place: passive pollination, natural pollination, manual pollination and pollinator's efficiency. These experiments established that pollinator species are: in C1 Apis mellifera, and in C2 and Xylocopa frontalis, Xylocopa lachnea and Epicharis sp.

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

    Directory of Open Access Journals (Sweden)

    Ana Maria Franco

    2011-09-01

    Full Text Available Pollinator guild organization and its consequences for reproduction in three synchronopatric species of Tibouchina (Melastomataceae. In co-flowering plant species, pollinator sharing can result in interspecific pollen transfer and fecundity reduction. Competition will be relaxed whenever there is a large amount of initial pollen supply or if each plant species occupies different habitat patches. Reproduction in Tibouchina cerastifolia (Naudin Cogn., T. clinopodifolia (DC. Cogn. and T. gracilis (Bonpl. Cogn. was studied in an area of Atlantic rainforest to examine whether synchronopatry induces time partitioning among pollinator species. Eleven bee species comprised the pollinator guild. Among pollinators, there were overlaps in bee species composition and in flower visitation time. Direct competition for pollen in Tibouchina Aubl. at the study site seems to lead to different activity periods among the bee species, in which Bombus pauloensis Friese,1913 was most active earlier, while the other species were active later in the day. Bombus pauloensis, the largest bee species recorded on Tibouchina flowers, was the most important and efficient pollinator. This species harvested pollen before the other species and had the shortest handling time. The plants reproduced sexually by selfing or outcrossing, and hybridization was not avoided by incompatibility reactions at the style. The avoidance of direct competition for pollen and no pollinator partitioning among the synchronopatric species of Tibouchina may reflect a facilitative interaction among these pioneer plants.

  11. The modularity of pollination networks

    DEFF Research Database (Denmark)

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

    2007-01-01

    In natural communities, species and their interactions are often organized as nonrandom networks, showing distinct and repeated complex patterns. A prevalent, but poorly explored pattern is ecological modularity, with weakly interlinked subsets of species (modules), which, however, internally...... 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...... almost 10,000 species and 20,000 links and tested for modularity by using a recently developed simulated annealing algorithm. All networks with >150 plant and pollinator species were modular, whereas networks with

  12. Pollination decays in biodiversity hotspots.

    Science.gov (United States)

    Vamosi, Jana C; Knight, Tiffany M; Steets, Janette A; Mazer, Susan J; Burd, Martin; Ashman, Tia-Lynn

    2006-01-24

    As pollinators decline globally, competition for their services is expected to intensify, and this antagonism may be most severe where the number of plant species is the greatest. Using meta-analysis and comparative phylogenetic analysis, we provide a global-scale test of whether reproduction becomes more limited by pollen receipt (pollen limitation) as the number of coexisting plant species increases. As predicted, we find a significant positive relationship between pollen limitation and species richness. In addition, this pattern is particularly strong for species that are obligately outcrossing and for trees relative to herbs or shrubs. We suggest that plants occurring in species-rich communities may be more prone to pollen limitation because of interspecific competition for pollinators. As a consequence, plants in biodiversity hotspots may have a higher risk of extinction and/or experience increased selection pressure to specialize on certain pollinators or diversify into different phenological niches. The combination of higher pollen limitation and habitat destruction represents a dual risk to tropical plant species that has not been previously identified.

  13. Eficiência de acessos de Cucurbita maxima como polinizadores de abóbora híbrida do tipo "Tetsukabuto" Efficiency of Cucurbita maxima accessions as pollinators in the commercial production of pumpkin ("Tetsukabuto" type

    Directory of Open Access Journals (Sweden)

    Warley Marcos Nascimento

    2008-12-01

    Full Text Available A abóbora tipo “Tetsukabuto” é um híbrido interespecífico, macho estéril, resultante do cruzamento entre Cucurbita maxima e C. moschata. Uma das estratégias utilizadas para produção comercial de frutos de “Tetsukabuto” tem sido o plantio adjacente e concomitante de acessos de C. maxima ou C. moschata como polinizadores. Este trabalho teve por objetivo avaliar a eficiência de diferentes acessos de C. maxima como fontes de pólen para produção comercial de abóbora tipo “Tetsukabuto”. A cultivar de moranga "Exposição" e o acesso "Nirvana" foram utilizados como polinizadores para produção de frutos de dois híbridos do tipo varietal “Tetsukabuto” ("Jabras" e "Kyoto". Foram avaliados os tratamentos (cruzamentos Jabras x Exposição, Jabras x Nirvana, Tetsukabuto x Exposição, Tetsukabuto x Nirvana, em quatro repetições. Foram determinados os parâmetros massa dos frutos, diâmetro dos frutos, espessura da polpa, número e massa de sementes. O acesso "Nirvana" (cultivar em fase de validação pode ser utilizado na produção comercial como polinizador de abóboras deste grupo varietal sem nenhum prejuízo quando comparado com a moranga "Exposição"."Tetsukabuto" pumpkins are interspecific hybrids between Cucurbita maxima x C. moschata accessions. Such hybrids, however, are often male-sterile due to the impaired ability of the staminate flowers to produce functional pollen. The use of intervening rows of staminate (pollen-donor plants is one strategy employed in order to have commercial fruit production. In the present work, two C. maxima accessions ["Exposição" (E and "Nirvana" (N] were employed as pollen-donors (staminate parents and their efficiency was compared considering fruit and seed yield parameters. Two pistillate Tetsukabuto hybrids ["Jabras" (J and "Kyoto Tetsukabuto" (KT] were employed in four possible unidirectional crosses (J x E, J x N, KT x E and KT x N. Fruits were produced using standard manual

  14. 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

  15. Scaling down from species to individuals: a flower-visitation network between individual honeybees and thistle plants

    DEFF Research Database (Denmark)

    Dupont, Yoko; Nielsen, Kristian T.; Olesen, Jens Mogens

    2011-01-01

    stems and monitored all floral visits. The constructed bipartite network of individual plants and bees had a high connectance and low nestedness, but it was not significantly modular. Frequency distributions of number of links per species (i.e. linkage level) had their best fit to a truncated power law......, and interactions were asymmetrical. Unipartite networks of either plants or bees had exceedingly short average path length and high clustering. Linkage level of plants increased with their number of flower heads and height of inflorescence (floral display parameters). Overall, the individual network of honeybees...... and thistles was denser linked than what is known from species pollination networks. Characteristics of both plants (e.g. floral display) and animals (e.g. foraging behaviour) are likely to generate this intra–specific, inter–individual link pattern. Such features of individual–individual networks may scale up...

  16. Sublethal pesticide doses negatively affect survival and the cellular responses in American foulbrood-infected honeybee larvae

    Science.gov (United States)

    López, Javier Hernández; Krainer, Sophie; Engert, Antonia; Schuehly, Wolfgang; Riessberger-Gallé, Ulrike; Crailsheim, Karl

    2017-02-01

    Disclosing interactions between pesticides and bee infections is of most interest to understand challenges that pollinators are facing and to which extent bee health is compromised. Here, we address the individual and combined effect that three different pesticides (dimethoate, clothianidin and fluvalinate) and an American foulbrood (AFB) infection have on mortality and the cellular immune response of honeybee larvae. We demonstrate for the first time a synergistic interaction when larvae are exposed to sublethal doses of dimethoate or clothianidin in combination with Paenibacillus larvae, the causative agent of AFB. A significantly higher mortality than the expected sum of the effects of each individual stressor was observed in co-exposed larvae, which was in parallel with a drastic reduction of the total and differential hemocyte counts. Our results underline that characterizing the cellular response of larvae to individual and combined stressors allows unmasking previously undetected sublethal effects of pesticides in colony health.

  17. The genetics of reproductive organ morphology in two Petunia species with contrasting pollination syndromes.

    Science.gov (United States)

    Hermann, Katrin; Klahre, Ulrich; Venail, Julien; Brandenburg, Anna; Kuhlemeier, Cris

    2015-05-01

    Switches between pollination syndromes have happened frequently during angiosperm evolution. Using QTL mapping and reciprocal introgressions, we show that changes in reproductive organ morphology have a simple genetic basis. In animal-pollinated plants, flowers have evolved to optimize pollination efficiency by different pollinator guilds and hence reproductive success. The two Petunia species, P. axillaris and P. exserta, display pollination syndromes adapted to moth or hummingbird pollination. For the floral traits color and scent, genetic loci of large phenotypic effect have been well documented. However, such large-effect loci may be typical for shifts in simple biochemical traits, whereas the evolution of morphological traits may involve multiple mutations of small phenotypic effect. Here, we performed a quantitative trait locus (QTL) analysis of floral morphology, followed by an in-depth study of pistil and stamen morphology and the introgression of individual QTL into reciprocal parental backgrounds. Two QTLs, on chromosomes II and V, are sufficient to explain the interspecific difference in pistil and stamen length. Since most of the difference in organ length is caused by differences in cell number, genes underlying these QTLs are likely to be involved in cell cycle regulation. Interestingly, conservation of the locus on chromosome II in a different P. axillaris subspecies suggests that the evolution of organ elongation was initiated on chromosome II in adaptation to different pollinators. We recently showed that QTLs for pistil and stamen length on chromosome II are tightly linked to QTLs for petal color and volatile emission. Linkage of multiple traits will enable major phenotypic change within a few generations in hybridizing populations. Thus, the genomic architecture of pollination syndromes in Petunia allows for rapid responses to changing pollinator availability.

  18. Effects of erectable glossal hairs on a honeybee's nectar-drinking strategy

    Science.gov (United States)

    Yang, Heng; Wu, Jianing; Yan, Shaoze

    2014-06-01

    With the use of a scanning electron microscope, we observe specific microstructures of the mouthpart of the Italian bee (Apis mellifera ligustica), especially the distribution and dimensions of hairs on its glossa. Considering the erection of glossal hairs for trapping nectar modifies the viscous dipping model in analyzing the drinking strategy of a honeybee. Theoretical estimations of volume intake rates with respect to sucrose solutions of different concentrations agree with experimental data, which indicates that erectable hairs can significantly increase the ability of a bee to acquire nectar efficiently. The comparison with experimental results also indicates that a honeybee may continuously augment its pumping power, rather than keep it constant, to drink nectar with sharply increasing viscosity. Under the modified assumption of increasing working power, we introduce the rate at which working power increases with viscosity and discuss the nature-preferred nectar concentration of 35% by theoretically calculating optimal concentration maximizing energetic intake rates under varying increasing rates. Finally, the ability of the mouthparts of the honeybee to transfer viscous nectar may inspire a concept for transporting microfluidics with a wide range of viscosities.

  19. Inhibitory neurotransmission and olfactory memory in honeybees.

    Science.gov (United States)

    El Hassani, Abdessalam Kacimi; Giurfa, Martin; Gauthier, Monique; Armengaud, Catherine

    2008-11-01

    In insects, gamma-aminobutyric acid (GABA) and glutamate mediate fast inhibitory neurotransmission through ligand-gated chloride channel receptors. Both GABA and glutamate have been identified in the olfactory circuit of the honeybee. Here we investigated the role of inhibitory transmission mediated by GABA and glutamate-gated chloride channels (GluCls) in olfactory learning and memory in honeybees. We combined olfactory conditioning with injection of ivermectin, an agonist of GluCl receptors. We also injected a blocker of glutamate transporters (L-trans-PDC) or a GABA analog (TACA). We measured acquisition and retention 1, 24 and 48 h after the last acquisition trial. A low dose of ivermectin (0.01 ng/bee) impaired long-term olfactory memory (48 h) while a higher dose (0.05 ng/bee) had no effect. Double injections of ivermectin and L-trans-PDC or TACA had different effects on memory retention, depending on the doses and agents combined. When the low dose of ivermectin was injected after Ringer, long-term memory was again impaired (48 h). Such an effect was rescued by injection of both TACA and L-trans-PDC. A combination of the higher dose of ivermectin and TACA decreased retention at 48 h. We interpret these results as reflecting the involvement of both GluCl and GABA receptors in the impairment of olfactory long-term memory induced by ivermectin. These results illustrate the diversity of inhibitory transmission and its implication in long-term olfactory memory in honeybees.

  20. Hox gene expression leads to differential hind leg development between honeybee castes.

    Science.gov (United States)

    Bomtorin, Ana Durvalina; Barchuk, Angel Roberto; Moda, Livia Maria; Simoes, Zila Luz Paulino

    2012-01-01

    Beyond the physiological and behavioural, differences in appendage morphology between the workers and queens of Apis mellifera are pre-eminent. The hind legs of workers, which are highly specialized pollinators, deserve special attention. The hind tibia of worker has an expanded bristle-free region used for carrying pollen and propolis, the corbicula. In queens this structure is absent. Although the morphological differences are well characterized, the genetic inputs driving the development of this alternative morphology remain unknown. Leg phenotype determination takes place between the fourth and fifth larval instar and herein we show that the morphogenesis is completed at brown-eyed pupa. Using results from the hybridization of whole genome-based oligonucleotide arrays with RNA samples from hind leg imaginal discs of pre-pupal honeybees of both castes we present a list of 200 differentially expressed genes. Notably, there are castes preferentially expressed cuticular protein genes and members of the P450 family. We also provide results of qPCR analyses determining the developmental transcription profiles of eight selected genes, including abdominal-A, distal-less and ultrabithorax (Ubx), whose roles in leg development have been previously demonstrated in other insect models. Ubx expression in workers hind leg is approximately 25 times higher than in queens. Finally, immunohistochemistry assays show that Ubx localization during hind leg development resembles the bristles localization in the tibia/basitarsus of the adult legs in both castes. Our data strongly indicate that the development of the hind legs diphenism characteristic of this corbiculate species is driven by a set of caste-preferentially expressed genes, such as those encoding cuticular protein genes, P450 and Hox proteins, in response to the naturally different diets offered to honeybees during the larval period.

  1. AmTAR2: Functional characterization of a honeybee tyramine receptor stimulating adenylyl cyclase activity.

    Science.gov (United States)

    Reim, Tina; Balfanz, Sabine; Baumann, Arnd; Blenau, Wolfgang; Thamm, Markus; Scheiner, Ricarda

    2017-01-01

    The biogenic monoamines norepinephrine and epinephrine regulate important physiological functions in vertebrates. Insects such as honeybees do not synthesize these neuroactive substances. Instead, they employ octopamine and tyramine for comparable physiological functions. These biogenic amines activate specific guanine nucleotide-binding (G) protein-coupled receptors (GPCRs). Based on pharmacological data obtained on heterologously expressed receptors, α- and β-adrenergic-like octopamine receptors are better activated by octopamine than by tyramine. Conversely, GPCRs forming the type 1 tyramine receptor clade (synonymous to octopamine/tyramine receptors) are better activated by tyramine than by octopamine. More recently, receptors were characterized which are almost exclusively activated by tyramine, thus forming an independent type 2 tyramine receptor clade. Functionally, type 1 tyramine receptors inhibit adenylyl cyclase activity, leading to a decrease in intracellular cAMP concentration ([cAMP] i ). Type 2 tyramine receptors can mediate Ca 2+ signals or both Ca 2+ signals and effects on [cAMP] i . We here provide evidence that the honeybee tyramine receptor 2 (AmTAR2), when heterologously expressed in flpTM cells, exclusively causes an increase in [cAMP] i . The receptor displays a pronounced preference for tyramine over octopamine. Its activity can be blocked by a series of established antagonists, of which mianserin and yohimbine are most efficient. The functional characterization of two tyramine receptors from the honeybee, AmTAR1 (previously named AmTYR1) and AmTAR2, which respond to tyramine by changing cAMP levels in opposite direction, is an important step towards understanding the actions of tyramine in honeybee behavior and physiology, particularly in comparison to the effects of octopamine. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Valuation of pollinator forage services provided by Eucalyptus Cladocalyx

    CSIR Research Space (South Africa)

    De Lange, Willem J

    2013-08-01

    Full Text Available legislation does not allow the importation of bees for pollination services from outside the province, the risk of unsecured forage is increased. Pollination replacement option All insect pollinators Managed pollinators Wild pollinators US$ millions...). Furthermore, colony collapse disorder outbreaks along with increases in sightings of predatory Vespula Germanica (German wasp or “yellow jackets”) in the Western Cape not only add to the pressure on the beekeeping industry, but also the wild pollinator...

  3. Pollen sources in the Bojanów forest complex identified on honeybee pollen load by microscopic analysis

    Directory of Open Access Journals (Sweden)

    Ernest Stawiarz

    2017-11-01

    Full Text Available The aim of this study was to determine sources of pollen for the honeybee in the Bojanów forest complex, Nowa Dęba Forest District (southeastern Poland. Sampling of pollen loads from bees extended from the beginning of May until the end of September 2016 and was carried out at 7-day intervals using pollen traps mounted at the entrance of beehives. A total of 73 pollen load samples were collected from the study area. Fifty-nine taxa from 31 plant families were identified in the analyzed material. From 4 to 21 taxa (average 9.5 were recorded in one sample. The pollen of Brassicaceae (“others”, Taraxacum type, Solidago type, and Rumex had the highest frequency in the pollen loads examined. Apart from these four taxa, pollen grains of Rubus type, Poaceae (“others”, Calluna, Fagopyrum, Trifolium repens s. l., Phacelia, Aster type, Melampyrum, Quercus, Cornus, and Veronica were recorded in the dominant pollen group. The forest habitat taxa that provided pollen rewards to honeybees in the Bojanów forest complex were the following: Rubus, Calluna, Prunus, Tilia, Frangula alnus, Pinus, Quercus, Cornus, Robinia pseudoacacia, Salix, and Vaccinium. Apart from forest vegetation, the species from meadows and wastelands adjacent to this forest complex, represented by Taraxacum, Rumex, Plantago, Poaceae, Trifolium repens, and Solidago, proved to be an important source of pollen. The study indicates that forest communities are a valuable source of pollen for pollinating insects from early spring through to late fall.

  4. Analysis of a normalised expressed sequence tag (EST) library from a key pollinator, the bumblebee Bombus terrestris.

    Science.gov (United States)

    Sadd, Ben M; Kube, Michael; Klages, Sven; Reinhardt, Richard; Schmid-Hempel, Paul

    2010-02-15

    The bumblebee, Bombus terrestris (Order Hymenoptera), is of widespread importance. This species is extensively used for commercial pollination in Europe, and along with other Bombus spp. is a key member of natural pollinator assemblages. Furthermore, the species is studied in a wide variety of biological fields. The objective of this project was to create a B. terrestris EST resource that will prove to be valuable in obtaining a deeper understanding of this significant social insect. A normalised cDNA library was constructed from the thorax and abdomen of B. terrestris workers in order to enhance the discovery of rare genes. A total of 29'428 ESTs were sequenced. Subsequent clustering resulted in 13'333 unique sequences. Of these, 58.8 percent had significant similarities to known proteins, with 54.5 percent having a "best-hit" to existing Hymenoptera sequences. Comparisons with the honeybee and other insects allowed the identification of potential candidates for gene loss, pseudogene evolution, and possible incomplete annotation in the honeybee genome. Further, given the focus of much basic research and the perceived threat of disease to natural and commercial populations, the immune system of bumblebees is a particularly relevant component. Although the library is derived from unchallenged bees, we still uncover transcription of a number of immune genes spanning the principally described insect immune pathways. Additionally, the EST library provides a resource for the discovery of genetic markers that can be used in population level studies. Indeed, initial screens identified 589 simple sequence repeats and 854 potential single nucleotide polymorphisms. The resource that these B. terrestris ESTs represent is valuable for ongoing work. The ESTs provide direct evidence of transcriptionally active regions, but they will also facilitate further functional genomics, gene discovery and future genome annotation. These are important aspects in obtaining a greater

  5. Pollinator interactions with yellow starthistle (Centaurea solstitialis across urban, agricultural, and natural landscapes.

    Directory of Open Access Journals (Sweden)

    Misha Leong

    Full Text Available Pollinator-plant relationships are found to be particularly vulnerable to land use change. Yet despite extensive research in agricultural and natural systems, less attention has focused on these interactions in neighboring urban areas and its impact on pollination services. We investigated pollinator-plant interactions in a peri-urban landscape on the outskirts of the San Francisco Bay Area, California, where urban, agricultural, and natural land use types interface. We made standardized observations of floral visitation and measured seed set of yellow starthistle (Centaurea solstitialis, a common grassland invasive, to test the hypotheses that increasing urbanization decreases 1 rates of bee visitation, 2 viable seed set, and 3 the efficiency of pollination (relationship between bee visitation and seed set. We unexpectedly found that bee visitation was highest in urban and agricultural land use contexts, but in contrast, seed set rates in these human-altered landscapes were lower than in natural sites. An explanation for the discrepancy between floral visitation and seed set is that higher plant diversity in urban and agricultural areas, as a result of more introduced species, decreases pollinator efficiency. If these patterns are consistent across other plant species, the novel plant communities created in these managed landscapes and the generalist bee species that are favored by human-altered environments will reduce pollination services.

  6. High specialisation in the pollination system of Mandevilla tenuifolia (J.C. Mikan) Woodson (Apocynaceae) drives the effectiveness of butterflies as pollinators.

    Science.gov (United States)

    de Araújo, L D A; Quirino, Z G M; Machado, I C

    2014-09-01

    Butterfly pollination in the tropics is considered somewhat effective or solely effective in a few plant species. In the present study, we tested the hypothesis that Mandevilla tenuifolia (Apocynaceae), which has floral attributes associated with psychophily, has strategies adapted to pollination by butterflies, restricting other floral visitors and making these insects act as efficient pollinators. We analysed the floral and reproductive biology of M. tenuifolia, as well as the frequency and efficiency of its flower visitors. M. tenuifolia is an herb whose flowers have strong herkogamy and secondary pollen presentation on the style head, which corresponds to 60.4% of pollen on the anthers. Flower longevity and the long period of receptivity of the stigmatic region associated with the large amount of pollen removed in the first visits suggest that flowers remain functionally female during part of anthesis. Butterflies, mainly of the families Nymphalidae and Pieridae, are the only pollinators of M. tenuifolia. Despite being self-compatible, M. tenuifolia depends on biotic vectors for fruit production. A non-significant difference in fruit set between controlled treatments and natural conditions suggests that the pollinators are efficient. The inclination resulting from the landing of butterflies on flowers, together with flower morphology, guiding the insect proboscis inside the floral tube, as well as the frequency and efficiency of butterfly visits, are evidence of the close relationship between butterflies and M. tenuifolia, and also of the efficiency of these insects as pollinators. © 2014 German Botanical Society and The Royal Botanical Society of the Netherlands.

  7. Floral biology and behavior of Africanized honeybees Apis mellifera in soybean (Glycine max L. Merril

    Directory of Open Access Journals (Sweden)

    Wainer César Chiari

    2005-05-01

    Full Text Available This research was carried out to evaluate the pollination by Africanized honeybees Apis mellifera, the floral biology and to observe the hoarding behavior in the soybean flowers (Glycine max Merril, var. BRS-133. The treatments were constituted of demarcated areas for free visitation of insects, covered areas by cages with a honeybee colony (A. mellifera and also covered areas by cage without insects visitation. All areas had 24 m² (4m x 6m. The soybean flowers stayed open for a larger time (82.82 ± 3.48 hours in covered area without honeybees. The stigma of the flowers was also more receptive (P=0.0021 in covered area without honeybees (87.3 ± 33.0% and at 10:42 o'clock was the schedule of greater receptivity. The pollen stayed viable in all treatments, the average was 99.60 ± 0.02%, which did not present differences among treatments. The percentage of abortion of the flowers was 82.91% in covered area without honeybees, this result was superior (P=0.0002 to the 52.66% and 53.95% of the treatments uncovered and covered with honeybees, respectively. Honeybees were responsible for 87.7% of the pollination accomplished by the insects. The medium amounts of total sugar and glucose measured in the nectar of the flowers were, 14.33 ± 0.96 mg/flower and 3.61 ± 0.36 mg/ flower, respectively, not showing differences (PEste experimento teve como objetivos avaliar a polinização realizada por abelhas Apis mellifera, estudar a biologia floral e observar o comportamento de coleta nas flores de soja (Glycine max L. Merril, variedade BRS-133 plantadas na região de Maringá-PR. Os tratamentos constituíram de áreas demarcadas de livre visitação por insetos, áreas cobertas por gaiolas, com uma colônia de abelhas (A. mellifera no seu interior e plantas também cobertas por gaiola que impedia a visitação por insetos. Todas as áreas possuíam 24 m² (4 m x 6 m. As flores de soja permaneceram abertas por um tempo maior (82,82 ± 3,48 horas no

  8. Honeybee (Apis mellifera ligustica) drone embryo proteomes.

    Science.gov (United States)

    Li, Jianke; Fang, Yu; Zhang, Lan; Begna, Desalegn

    2011-03-01

    Little attention has been paid to the drone honeybee (Apis mellifera ligustica) which is a haploid individual carrying only the set of alleles that it inherits from its mother. Molecular mechanisms underlying drone embryogenesis are poorly understood. This study evaluated protein expression profiles of drone embryogenesis at embryonic ages of 24, 48 and 72h. More than 100 reproducible proteins were analyzed by mass spectrometry on 2D electrophoresis gels. Sixty-two proteins were significantly changed at the selected three experimental age points. Expression of the metabolic energy requirement-related protein peaked at the embryonic age of 48h, whereas development and metabolizing amino acid-related proteins expressed optimally at 72h. Cytoskeleton, protein folding and antioxidant-related proteins were highly expressed at 48 and 72h. Protein networks of the identified proteins were constructed and protein expressions were validated at the transcription level. This first proteomic study of drone embryogenesis in the honeybee may provide geneticists an exact timetable and candidate protein outline for further manipulations of drone stem cells. Crown Copyright © 2010. Published by Elsevier Ltd. All rights reserved.

  9. Pollination Reservoirs in Lowbush Blueberry (Ericales: Ericaceae).

    Science.gov (United States)

    Venturini, E M; Drummond, F A; Hoshide, A K; Dibble, A C; Stack, L B

    2017-04-01

    Pollinator-dependent agriculture heavily relies upon a single pollinator-the honey bee. To diversify pollination strategies, growers are turning to alternatives. Densely planted reservoirs of pollen- and nectar-rich flowers (pollination reservoirs, hereafter "PRs") may improve pollination services provided by wild bees. Our focal agroecosystem, lowbush blueberry (Vaccinium angustifolium Aiton), exists in a simple landscape uniquely positioned to benefit from PRs. First, we contrast bee visitation rates and use of three types of PR. We consider the effects of PRs on wild bee diversity and the composition of bumble bee pollen loads. We contrast field-level crop pollination services between PRs and controls four years postestablishment. Last, we calculate the time to pay for PR investment. Social bees preferentially used clover plantings; solitary bees preferentially used wildflower plantings. On average, bumble bee pollen loads in treatment fields contained 37% PR pollen. PRs significantly increased visitation rates to the crop in year 4, and exerted a marginally significant positive influence on fruit set. The annualized costs of PRs were covered by the fourth year using the measured increase in pollination services. Our findings provide evidence of the positive impact of PRs on crop pollination services. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America.

  10. 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.

  11. 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.

  12. 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...

  13. Private channels in plant-pollinator mutualisms

    Science.gov (United States)

    Chen, Chun; Hossaert-McKey, Martine

    2010-01-01

    Volatile compounds often mediate plant-pollinator interactions, and may promote specialization in plant-pollinator relationships, notably through private channels of unusual compounds. Nevertheless, the existence of private channels, i.e., the potential for exclusive communication via unique signals and receptors, is still debated in the literature. Interactions between figs and their pollinating wasps offer opportunities for exploring this concept. Several experiments have demonstrated that chemical mediation is crucial in ensuring the encounter between figs and their species-specific pollinators. Indeed, chemical messages emitted by figs are notably species- and developmental stage-specific, making them reliable cues for the pollinator. In most cases, the species-specificity of wasp attraction is unlikely to result from the presence of a single specific compound. Nevertheless, a recent paper on the role of scents in the interaction between Ficus semicordata and its pollinating wasp Ceratosolen gravelyi showed that a single compound, 4-methylanisole, is the main signal compound in the floral scent, and is sufficient by itself to attract the obligate pollinator. Mainly focusing on these results, we propose here that a floral scent can act as a private channel, attracting only the highly specific pollinator. PMID:20484975

  14. 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

  15. Population density of oil palm pollinator weevil Elaeidobius kamerunicus based on seasonal effect and age of oil palm

    Science.gov (United States)

    Daud, Syarifah Nadiah Syed Mat; Ghani, Idris Abd.

    2016-11-01

    The pollinating weevil, Elaedobius kamerunicus (EK) has been known to be the most efficient insect pollinator of oil palm, and has successfully improved the oil palm pollination and increased the yield. Its introduction has greatly reduced the need for assisted pollination. The purpose of this study was to identify the population density of oil palm pollinator weevil EK using the concept of pollinator force and to relate the population density with the seasonal effect and the age of oil palm at Lekir Oil Palm Plantation Batu 14, Perak, Peninsular Malaysia. The pollinator force of the weevil was sustained at a range between 3095.2 to 19126.1 weevils per ha. The overall mean of weevil per spikelet shows that the range of weevil was between 13.51 and 54.06 per spikelet. There was no correlation between rainfall and population density of EK. However, positive correlation was obtained between weevil density and the number of anthesising female inflorescence of oil palm (r= 0.938, poil palm stands had significantly different population density than that of a 8-year old oil palm stand. The information of this study should be useful as a baseline data to investigate why there is such a wide range of weevils per ha or spikelet. Further study should also be done to relate the number pollinator force per spikelete and the Fresh fruit Bunch (FFB), fruit set or fruit to bunch ratio.

  16. Determining the Pollinizer for Pecan Cultivars

    Directory of Open Access Journals (Sweden)

    Fereidoon Ajamgard

    2017-05-01

    Full Text Available This study was conducted to determine the best pollinizer for five selected pecan cultivars in southwest of Iran at Safiabad Agricultural Research Center in 2014-2015. The cultivars included: 'GraTex', '10J', 'Wichita 6J', 'GraKing', 'Choctaw' as pollinated cultivars (♀ and 'GraTex', 'Peruque', 'Comanche 4M', '10J', 'Wichita 6J', 'Mohawk', 'Mahan', 'Stuart 2J', '3J', 'Stuart 4J', 'GraKing', 'Choctaw', 'Apache', '6M', 'Wichita 7J' and 'Comanche 5M.' as pollinizer cultivars (♂. In the first step, a pollination chart of cultivars was determined in two years. The pollination chart of cultivars showed that all the cultivars investigated during this study were dichogamous and also protogynous except for the 'Peruque'. ‘GraKing’ had the longest duration of shedding pollen. Pollination chart showed that 'Peruque', ‘GraKing’, and 'Stuart 2J' had flowering overlap with the selected cultivars. Pollen germination test showed that the germination ability was different among the cultivars. It was 45% for 'GraKing' and 35% for 'Peruque', which were both recommended as pollinizers in this study. '6M', 'GraTex' and 'Stuart 4J' cultivars had the highest pollen germination percentage of 65%, 60% and 60%, respectively. The results of controlled pollinationtest showed that different pollen sources had no significant effect on nuts per cluster but self-pollinated all of the cultivars significantly reduced fruit set in first and second years. Based on the present research, pollination in pecan orchard was necessary for adequate yield. Also, 'Peruque', 'GraKing' and 'Stuart 2J' were the best pollinizers for five selected cultivars in southwest of Iran.

  17. Genetic diversity and population structure of Chinese honeybees ...

    African Journals Online (AJOL)

    user

    2011-02-28

    Feb 28, 2011 ... honeybees (Apis cerana) under microsatellite markers. Ting Ji, Ling Yin and ... from Apis mellifera introduced into China since 1896 (Yang, 2005). With the ..... Commercial and Feral Honey Bees in Western Australia. J. Econ.

  18. Notch signalling mediates reproductive constraint in the adult worker honeybee

    Science.gov (United States)

    Duncan, Elizabeth J.; Hyink, Otto; Dearden, Peter K.

    2016-01-01

    The hallmark of eusociality is the reproductive division of labour, in which one female caste reproduces, while reproduction is constrained in the subordinate caste. In adult worker honeybees (Apis mellifera) reproductive constraint is conditional: in the absence of the queen and brood, adult worker honeybees activate their ovaries and lay haploid male eggs. Here, we demonstrate that chemical inhibition of Notch signalling can overcome the repressive effect of queen pheromone and promote ovary activity in adult worker honeybees. We show that Notch signalling acts on the earliest stages of oogenesis and that the removal of the queen corresponds with a loss of Notch protein in the germarium. We conclude that the ancient and pleiotropic Notch signalling pathway has been co-opted into constraining reproduction in worker honeybees and we provide the first molecular mechanism directly linking ovary activity in adult worker bees with the presence of the queen. PMID:27485026

  19. CRISPR-Cas9 gene editing in honeybee and pig

    DEFF Research Database (Denmark)

    Pen, Anja

    2018-01-01

    Creating animal models by using genome modification has gotten significantly more accessible thanks to the CRISPR-Cas9 technique. In this study, we aimed to the implement the CRISPR-Cas9 methodology in the European honeybee (Apis mellifera) and pig (Sus scrofa) for generation of animal models. We...... want to use these animal models to study the development of honeybees and the pathology of amyotrophic lateral sclerosis (ALS) in a pig model of human disease. In order to simplify the production of these animal models, we test the use of sperm mediated gene transfer (SMGT) in combination with CRISPR...... mechanisms of honeybee development using genome modification will aid in uncovering these complex genetic regulatory systems. In honeybees, we have attempted to induce genome modification in the cinnabar gene through microinjection and feeding of CRISPR-Cas9 components to larvae. Additionally, we tested...

  20. Honeybee colony marketing and its implications for queen rearing ...

    African Journals Online (AJOL)

    Honeybee colony marketing and its implications for queen rearing and beekeeping development in Werieleke ... Thus, colony marketing is an important venture in Werieleke district of Tigray region. ... EMAIL FULL TEXT EMAIL FULL TEXT

  1. Visual discrimination transfer and modulation by biogenic amines in honeybees.

    Science.gov (United States)

    Vieira, Amanda Rodrigues; Salles, Nayara; Borges, Marco; Mota, Theo

    2018-05-10

    For more than a century, visual learning and memory have been studied in the honeybee Apis mellifera using operant appetitive conditioning. Although honeybees show impressive visual learning capacities in this well-established protocol, operant training of free-flying animals cannot be combined with invasive protocols for studying the neurobiological basis of visual learning. In view of this, different attempts have been made to develop new classical conditioning protocols for studying visual learning in harnessed honeybees, though learning performance remains considerably poorer than that for free-flying animals. Here, we investigated the ability of honeybees to use visual information acquired during classical conditioning in a new operant context. We performed differential visual conditioning of the proboscis extension reflex (PER) followed by visual orientation tests in a Y-maze. Classical conditioning and Y-maze retention tests were performed using the same pair of perceptually isoluminant chromatic stimuli, to avoid the influence of phototaxis during free-flying orientation. Visual discrimination transfer was clearly observed, with pre-trained honeybees significantly orienting their flights towards the former positive conditioned stimulus (CS+), thus showing that visual memories acquired by honeybees are resistant to context changes between conditioning and the retention test. We combined this visual discrimination approach with selective pharmacological injections to evaluate the effect of dopamine and octopamine in appetitive visual learning. Both octopaminergic and dopaminergic antagonists impaired visual discrimination performance, suggesting that both these biogenic amines modulate appetitive visual learning in honeybees. Our study brings new insight into cognitive and neurobiological mechanisms underlying visual learning in honeybees. © 2018. Published by The Company of Biologists Ltd.

  2. Proteomic analysis of honeybee (Apis mellifera L. pupae head development.

    Directory of Open Access Journals (Sweden)

    Aijuan Zheng

    Full Text Available The honeybee pupae development influences its future adult condition as well as honey and royal jelly productions. However, the molecular mechanism that regulates honeybee pupae head metamorphosis is still poorly understood. To further our understand of the associated molecular mechanism, we investigated the protein change of the honeybee pupae head at 5 time-points using 2-D electrophoresis, mass spectrometry, bioinformatics, quantitative real-time polymerase chain reaction and Western blot analysis. Accordingly, 58 protein spots altered their expression across the 5 time points (13-20 days, of which 36 proteins involved in the head organogenesis were upregulated during early stages (13-17 days. However, 22 proteins involved in regulating the pupae head neuron and gland development were upregulated at later developmental stages (19-20 days. Also, the functional enrichment analysis further suggests that proteins related to carbohydrate metabolism and energy production, development, cytoskeleton and protein folding were highly involved in the generation of organs and development of honeybee pupal head. Furthermore, the constructed protein interaction network predicted 33 proteins acting as key nodes of honeybee pupae head growth of which 9 and 4 proteins were validated at gene and protein levels, respectively. In this study, we uncovered potential protein species involved in the formation of honeybee pupae head development along with their specific temporal requirements. This first proteomic result allows deeper understanding of the proteome profile changes during honeybee pupae head development and provides important potential candidate proteins for future reverse genetic research on honeybee pupae head development to improve the performance of related organs.

  3. 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.

  4. Aspects of Honeybee Natural History According to the Solega

    Directory of Open Access Journals (Sweden)

    Aung Si

    2013-07-01

    Full Text Available Honeybees and their products are highly prized by many cultures around the world, and as a result, indigenous communities have come to possess rich and detailed knowledge of the biology of these important insects. In this paper, I present an in-depth investigation into some aspects of honeybee natural history, as related to me by the Solega people of southern India. The Solega recognize, name, and exploit four honeybee species, and are well aware of the geographical and temporal distributions of each one. In spite of not being beekeepers – as they only forage for wild honey – their knowledge of obscure and complex phenomena such as honeybee gender and reproduction rivals that of comparable, non-industrial beekeeping societies. Swarming, another hard-to-understand honeybee behavior, is also accurately explained by Solega consultants. I contrast this knowledge to that of European bee-keeping cultures, as evidenced by the writings of Aristotle and 18th century European beekeepers. This paper shows that the Solega have a reliable and internally consistent body of honeybee knowledge based entirely on brief encounters with these wild, migratory insects that are present in the forest for only part of the year.

  5. 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

  6. Persistence of pollination mutualisms in the presence of ants.

    Science.gov (United States)

    Wang, Yuanshi; Wang, Shikun

    2015-01-01

    This paper considers plant-pollinator-ant systems in which the plant-pollinator interaction is mutualistic but ants have both positive and negative effects on plants. The ants also interfere with pollinators by preventing them from accessing plants. While a Beddington-DeAngelis (BD) formula can describe the plant-pollinator interaction, the formula is extended in this paper to characterize the pollination mutualism under the ant interference. Then, a plant-pollinator-ant system with the extended BD functional response is discussed, and global dynamics of the model demonstrate the mechanisms by which pollination mutualism can persist in the presence of ants. When the ant interference is strong, it can result in extinction of pollinators. Moreover, if the ants depend on pollination mutualism for survival, the strong interference could drive pollinators into extinction, which consequently lead to extinction of the ants themselves. When the ant interference is weak, a cooperation between plant-ant and plant-pollinator mutualisms could occur, which promotes survival of both ants and pollinators, especially in the case that ants (respectively, pollinators) cannot survive in the absence of pollinators (respectively, ants). Even when the level of ant interference remains invariant, varying ants' negative effect on plants can result in survival/extinction of both ants and pollinators. Therefore, our results provide an explanation for the persistence of pollination mutualism when there exist ants.

  7. Profiling crop pollinators: life history traits predict habitat use and crop visitation by Mediterranean wild bees.

    Science.gov (United States)

    Pisanty, Gideon; Mandelik, Yael

    2015-04-01

    -history traits of bee communities can help assess the pollination services they are likely to provide (when taking into account single-visit pollination efficiency). The ecotone between agricultural fields and surrounding habitats is a major barrier that filters many bee species, particularly with regard to their nesting requirements. Thus, greater attention should be given to management practices that encourage pollinators to live and nest, and not only forage, within fields.

  8. Proximity to Woodland and Landscape Structure Drive Pollinator Visitation in Apple Orchard Ecosystem

    Directory of Open Access Journals (Sweden)

    Neelendra K Joshi

    2016-04-01

    Full Text Available Landscapes of farms and adjacent areas are known to influence abundance of various arthropods such as pollinators in commercial agricultural ecosystems. In this context, we examined the effect of heterogeneous landscapes surrounding and including commercial apple orchards on pollinator visitation and foraging distance during bloom period from 2011 to 2013 in Pennsylvania. Our results showed that the frequency of feral honeybees and solitary bee visits within an apple orchard depends on the proximity of the orchard to an unmanaged habitat (primarily comprised of forest. At the landscape scale, we found that the Mean Proximity Index, the Largest Patch Index and the Number of Patches positively correlated with the visitation rate of dominant bee taxa (Apis mellifera, Bombus spp. and solitary bees visiting apple flowers at low spatial scales (up to 500 m around the orchards. The Mean Proximity Index at 500 m was related to bee visitation patterns, especially for solitary bees and A. mellifera. Bees in all our study sites preferred to forage in areas with large homogenous patches up to 500 m around an apple orchard. This effect can be attributed to the mass flowering of apples that formed the largest proportion of the 500 m spatial scale. The Number of Patches at 250 m spatial scale was positively correlated with bee visitation, especially Bombus spp., probably because these areas had more habitats and more resources required by these bees. We conclude that retaining unmanaged habitats closer to commercial apple orchards will maintain biodiversity within the landscapes and insure pollination services to apples.

  9. 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)

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

    2017-01-01

    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...

  10. Bee Pollination in Syagrus orinocensis (ARECACEAE in the Colombian Orinoquia

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    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.

  11. Do abundance and proximity of the alien Impatiens glandulifera affect pollination and reproductive success of two sympatric co-flowering native species?

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    Anne-Laure Jacquemart

    2012-12-01

    Full Text Available In invasion ecology, potential impacts of aliens on native flora are still under debate. Our aim was to determine the pollinator mediated effects of both proximity and abundance of an alien species on the reproductive success of natives. We chose the highly invasive Impatiens glandulifera and two native species: Epilobium angustifolium and Aconitum napellus ssp. lusitanicum. These species share characteristics allowing for pollination interactions: similar biotopes, overlapping flowering periods and same main pollinators. The effects of abundance (5, 25 and 100 individuals and proximity (0 and 15 m of the alien on visitation rate, insect behaviour, pollen deposition and reproductive success of both natives were investigated during 2 flowering seasons. We used centred visitation rates as they can be directly interpreted as a positive or negative effect of the invasive.Both abundance and proximity of the alien increased bumblebee visitation rates to both natives. On the other hand, abundance of the exotic species had a slight negative effect on honeybee visits to natives while its proximity had no effect. The behaviour of bumblebees changed as visitors left significantly more often the native plants for I. glandulifera when its abundance increased. As a consequence of this “inconstancy”, bees deposited considerable quantities of alien pollen on native stigmas. Nevertheless, this interspecific pollen transfer did not decrease seed set in natives. Self-compatibility and high attractiveness of both native species probably alleviate the risk of altered pollinator services and reproductive success due to the invader in natural populations.

  12. Migration effects on population dynamics of the honeybee-mite interactions

    Science.gov (United States)

    Honeybees are amazing and highly beneficial insect species that play important roles in undisturbed and agricultural ecosystems. Unfortunately, honeybees are increasingly threatened by numerous factors, most notably the parasitic Varroa mite (Varroa destructor Anderson and Trueman). A recent field s...

  13. Floral odor learning within the hive affects honeybees' foraging decisions

    Science.gov (United States)

    Arenas, Andrés; Fernández, Vanesa M.; Farina, Walter M.

    2007-03-01

    Honeybees learn odor cues quickly and efficiently when visiting rewarding flowers. Memorization of these cues facilitates the localization and recognition of food sources during foraging flights. Bees can also use information gained inside the hive during social interactions with successful foragers. An important information cue that can be learned during these interactions is food odor. However, little is known about how floral odors learned in the hive affect later decisions of foragers in the field. We studied the effect of food scent on foraging preferences when this learning is acquired directly inside the hive. By using in-hive feeders that were removed 24 h before the test, we showed that foragers use the odor information acquired during a 3-day stimulation period with a scented solution during a food-choice situation outside the nest. This bias in food preference is maintained even 24 h after the replacement of all the hive combs. Thus, without being previously collected outside by foragers, food odors learned within the hive can be used during short-range foraging flights. Moreover, correct landings at a dual-choice device after replacing the storing combs suggests that long-term memories formed within the colony can be retrieved while bees search for food in the field.

  14. Ecological intensification to mitigate impacts of conventional intensive land use on pollinators and pollination.

    Science.gov (United States)

    Kovács-Hostyánszki, Anikó; Espíndola, Anahí; Vanbergen, Adam J; Settele, Josef; Kremen, Claire; Dicks, Lynn V

    2017-05-01

    Worldwide, human appropriation of ecosystems is disrupting plant-pollinator communities and pollination function through habitat conversion and landscape homogenisation. Conversion to agriculture is destroying and degrading semi-natural ecosystems while conventional land-use intensification (e.g. industrial management of large-scale monocultures with high chemical inputs) homogenises landscape structure and quality. Together, these anthropogenic processes reduce the connectivity of populations and erode floral and nesting resources to undermine pollinator abundance and diversity, and ultimately pollination services. Ecological intensification of agriculture represents a strategic alternative to ameliorate these drivers of pollinator decline while supporting sustainable food production, by promoting biodiversity beneficial to agricultural production through management practices such as intercropping, crop rotations, farm-level diversification and reduced agrochemical use. We critically evaluate its potential to address and reverse the land use and management trends currently degrading pollinator communities and potentially causing widespread pollination deficits. We find that many of the practices that constitute ecological intensification can contribute to mitigating the drivers of pollinator decline. Our findings support ecological intensification as a solution to pollinator declines, and we discuss ways to promote it in agricultural policy and practice. © 2017 The Authors. Ecology Letters published by CNRS and John Wiley & Sons Ltd.

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

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    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.

  16. Breeding system and pollination biology of paeonia delavayi (peaoniaceae), an endangered plant in the southwest of china

    International Nuclear Information System (INIS)

    Zheng, B.; Wang, Y.; Zhou, L

    2014-01-01

    Breeding system and pollination biology of Paeonia delavayi (Peaoniaceae) from Shangri-La, Yunnan Province, southwest of China were studied. Flowering phenologies and flower visitors were observed or collected from 2008 to 2011. The pollen viability, stigma receptivity and pollination efficiency of different visitors were detected and tested. The florescence lasted for 6- 9d in a single flower from mid-May to late June. A high percentage of flower damage promoted early anther dehiscence. Flowers started disseminating pollen at 1-2 d after flowering, and lasted for 5-6 d. Pollen viability could be preserved for more than 10 d at normal temperature. High seed rate from the stigma was observed at 1 d before flowering to 3d after flowering, and the dissemination hysteresis was defined as protogyny. The P/O ratios were 6,124 to 9,713:1, suggesting that the larger quantity of pollen to increased the seed setting rate. Three species of bees, eight species of beetles, seven species of syrphid flies, four species of ants, and three species of butterflies were observed on the flowers. P. delavayi rewarded to the visitors by releasing fragrance, providing pollen and nectar. On the bodies of the visitors under stereomicroscope and scanning electron microscope (SEM), much pollen from the plants of similar flowering period inner community were found which indicated that these incompatible visitors were not species-specific pollinators. The bagging experiments showed that P. delavayi was selfincompatible and no apomixes. Anemophily only played a minor role in the fertilization. A few seeds with poor plumpness can be produced by geitonogamy. Seed setting rate of artificial xenogamy was higher than natural pollination. Artificial control of the visitors' species showed bees being the most important pollinators. Beetles and ants participated in pollination to someextent and were unstable. Syrphid flies and butterflies were very unreliable with low pollination efficiency

  17. 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.

  18. Find Best Management Practices to Protect Pollinators

    Science.gov (United States)

    Resources and ways to reduce potential pesticide exposure to honey bees and other pollinators include new pesticide labels, neonicotinoid insecticide information, reducing dust from treated seed, and state-level efforts.

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

    Science.gov (United States)

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

    2013-01-01

    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.

  20. 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.

  1. 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.

  2. Premature attraction of pollinators to inaccessible figs of Ficus altissima: a search for ecological and evolutionary consequences.

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    Yuan Zhang

    Full Text Available Adult life spans of only one or two days characterise life cycles of the fig wasps (Agaonidae that pollinate fig trees (Ficus spp., Moraceae. Selection is expected to favour traits that maximise the value of the timing of encounters between such mutualistic partners, and fig wasps are usually only attracted to their hosts by species- and developmental-stage specific volatiles released from figs at the time when they are ready to be entered, oviposited in and pollinated. We found that Ficus altissima is exceptional, because it has persistent tight-fitting bud covers that prevent its Eupristina altissima pollinator (and a second species of 'cheater' agaonid from entering its figs for several days after they start to be attracted. We examined the consequences of delayed entry for the figs and fig wasps and tested whether delayed entry has been selected to increase adult longevity. We found that older pollinators produced fewer and smaller offspring, but seed production was more efficient. Pollinator offspring ratios also varied depending on the age of figs they entered. The two agaonids from F. altissima lived slightly longer than six congeners associated with typical figs, but this was explainable by their larger body sizes. Delayed entry generates reproductive costs, especially for the pollinator. This opens an interesting perspective on the coevolution of figs and their pollinators and on the nature of mutualistic interactions in general.

  3. Flower specialisation: the occluded corolla of snapdragons (Antirrhinum) exhibits two pollinator niches of large long-tongued bees.

    Science.gov (United States)

    Vargas, P; Liberal, I; Ornosa, C; Gómez, J M

    2017-09-01

    Flower specialisation of angiosperms includes the occluded corollas of snapdragons (Antirrhinum and some relatives), which have been postulated to be one of the most efficient structures to physical limit access to pollinators. The Iberian Peninsula harbours the highest number of species (18 Iberian of the 20 species of Antirrhinum) that potentially share similar pollinator fauna. Crossing experiments with 18 Iberian species from this study and literature revealed a general pattern of self-incompatibility (SI) - failure in this SI system has been also observed in a few plants - which indicates the need for pollinator agents in Antirrhinum pollination. Field surveys in natural conditions (304 h) found flower visitation (>85%) almost exclusively by 11 species of bee (Anthophora fulvitarsis, Anthophora plumipes, Anthidium sticticum, Apis mellifera, Bombus hortorum, Bombus pascuorum, Bombus ruderatus, Bombus terrestris, Chalicodoma lefebvrei, Chalicodoma pyrenaica and Xylocopa violacea). This result covering the majority of Antirrhinum species suggests that large bees of the two long-tongued bee families (Megachilidae, Apidae) are the major pollinators of Antirrhinum. A bipartite modularity analysis revealed two pollinator systems of long-tongued bees: (i) the long-studied system of bumblebees (Bombus spp.) associated with nine primarily northern species of Antirrhinum; and (ii) a newly proposed pollinator system involving other large bees associated with seven species primarily distributed in southern Mediterranean areas. © 2017 German Botanical Society and The Royal Botanical Society of the Netherlands.

  4. Pesticide residues in honeybees, honey and bee pollen by LC-MS/MS screening: reported death incidents in honeybees.

    Science.gov (United States)

    Kasiotis, Konstantinos M; Anagnostopoulos, Chris; Anastasiadou, Pelagia; Machera, Kyriaki

    2014-07-01

    The aim of this study was to investigate reported cases of honeybee death incidents with regard to the potential interrelation to the exposure to pesticides. Thus honeybee, bee pollen and honey samples from different areas of Greece were analyzed for the presence of pesticide residues. In this context an LC-ESI-MS/MS multiresidue method of total 115 analytes of different chemical classes such as neonicotinoids, organophosphates, triazoles, carbamates, dicarboximides and dinitroanilines in honeybee bodies, honey and bee pollen was developed and validated. The method presents good linearity over the ranges assayed with correlation coefficient values r(2)≥0.99, recoveries ranging for all matrices from 59 to 117% and precision (RSD%) values ranging from 4 to 27%. LOD and LOQ values ranged - for honeybees, honey and bee pollen - from 0.03 to 23.3 ng/g matrix weight and 0.1 up to 78 ng/g matrix weight, respectively. Therefore this method is sufficient to act as a monitoring tool for the determination of pesticide residues in cases of suspected honeybee poisoning incidents. From the analysis of the samples the presence of 14 active substances was observed in all matrices with concentrations ranging for honeybees from 0.3 to 81.5 ng/g, for bee pollen from 6.1 to 1273 ng/g and for honey one sample was positive to carbendazim at 1.6 ng/g. The latter confirmed the presence of such type of compounds in honeybee body and apicultural products. Copyright © 2014 Elsevier B.V. All rights reserved.

  5. A robotic system for researching social integration in honeybees.

    Directory of Open Access Journals (Sweden)

    Karlo Griparić

    Full Text Available In this paper, we present a novel robotic system developed for researching collective social mechanisms in a biohybrid society of robots and honeybees. The potential for distributed coordination, as observed in nature in many different animal species, has caused an increased interest in collective behaviour research in recent years because of its applicability to a broad spectrum of technical systems requiring robust multi-agent control. One of the main problems is understanding the mechanisms driving the emergence of collective behaviour of social animals. With the aim of deepening the knowledge in this field, we have designed a multi-robot system capable of interacting with honeybees within an experimental arena. The final product, stationary autonomous robot units, designed by specificaly considering the physical, sensorimotor and behavioral characteristics of the honeybees (lat. Apis mallifera, are equipped with sensing, actuating, computation, and communication capabilities that enable the measurement of relevant environmental states, such as honeybee presence, and adequate response to the measurements by generating heat, vibration and airflow. The coordination among robots in the developed system is established using distributed controllers. The cooperation between the two different types of collective systems is realized by means of a consensus algorithm, enabling the honeybees and the robots to achieve a common objective. Presented results, obtained within ASSISIbf project, show successful cooperation indicating its potential for future applications.

  6. A robotic system for researching social integration in honeybees.

    Science.gov (United States)

    Griparić, Karlo; Haus, Tomislav; Miklić, Damjan; Polić, Marsela; Bogdan, Stjepan

    2017-01-01

    In this paper, we present a novel robotic system developed for researching collective social mechanisms in a biohybrid society of robots and honeybees. The potential for distributed coordination, as observed in nature in many different animal species, has caused an increased interest in collective behaviour research in recent years because of its applicability to a broad spectrum of technical systems requiring robust multi-agent control. One of the main problems is understanding the mechanisms driving the emergence of collective behaviour of social animals. With the aim of deepening the knowledge in this field, we have designed a multi-robot system capable of interacting with honeybees within an experimental arena. The final product, stationary autonomous robot units, designed by specificaly considering the physical, sensorimotor and behavioral characteristics of the honeybees (lat. Apis mallifera), are equipped with sensing, actuating, computation, and communication capabilities that enable the measurement of relevant environmental states, such as honeybee presence, and adequate response to the measurements by generating heat, vibration and airflow. The coordination among robots in the developed system is established using distributed controllers. The cooperation between the two different types of collective systems is realized by means of a consensus algorithm, enabling the honeybees and the robots to achieve a common objective. Presented results, obtained within ASSISIbf project, show successful cooperation indicating its potential for future applications.

  7. Pollination and reproduction of a self-incompatible forest herb in hedgerow corridors and forest patches.

    Science.gov (United States)

    Schmucki, Reto; de Blois, Sylvie

    2009-07-01

    Habitat-corridors are assumed to counteract the negative impacts of habitat loss and fragmentation, but their efficiency in doing so depends on the maintenance of ecological processes in corridor conditions. For plants dispersing in linear habitats, one of these critical processes is the maintenance of adequate pollen transfer to insure seed production within the corridor. This study focuses on a common, self-incompatible forest herb, Trillium grandiflorum, to assess plant-pollinator interactions and the influence of spatial processes on plant reproduction in hedgerow corridors compared to forests. First, using pollen supplementation experiments over 2 years, we quantified the extent of pollen limitation in both habitats, testing the prediction of greater limitation in small hedgerow populations than in forests. While pollen limitation of fruit and seed set was common, its magnitude did not differ between habitats. Variations among sites, however, suggested an influence of landscape context on pollination services. Second, we examined the effect of isolation on plant reproduction by monitoring fruit and seed production, as well as pollinator activity and assemblage, in small flower arrays transplanted in hedgerows at increasing distances from forest and from each other. We detected no difference in the proportion of flowers setting fruit or in pollinator activity with isolation, but we observed some differences in pollinator assemblages. Seed set, on the other hand, declined significantly with increasing isolation in the second year of the study, but not in the first year, suggesting altered pollen transfer with distance. Overall, plants in hedgerow corridors and forests benefited from similar pollination services. In this system, plant-pollinator interactions and reproduction seem to be influenced more by variations in resource distribution over years and landscapes than by local habitat conditions.

  8. 78 FR 10167 - Pollinator Summit: Status of Ongoing Collaborative Efforts To Protect Pollinators; Notice of...

    Science.gov (United States)

    2013-02-13

    ... exposure to pollinators. Pollinators are an important component of agricultural production, critical to food and ecosystems, and must be protected so that they can continue to play this important role. The... may be of particular interest to, but is not limited to the following entities: Agricultural workers...

  9. Parallel Declines in Pollinators and Insect-Pollinated Plants in Britain and the Netherlands

    NARCIS (Netherlands)

    Biesmeijer, J.S.; Roberts, S.P.M.; Reemer, M.; Ohlemüller, R.; Edwards, M.; Peeters, T.; Schaffers, A.P.; Potts, S.G.; Kleukers, R.; Thomas, C.D.; Settele, J.; Kunin, W.E.

    2006-01-01

    Despite widespread concern about declines in pollination services, little is known about the patterns of change in most pollinator assemblages. By studying bee and hoverfly assemblages in Britain and the Netherlands, we found evidence of declines (pre-versus post-1980) in local bee diversity in both

  10. 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...

  11. Patients with massive honeybee stings: report of four cases

    Directory of Open Access Journals (Sweden)

    Shahidi Sh

    2008-11-01

    Full Text Available "nBackground: Insect stings can cause local or systemic reactions that range from mild to fatal, and are among the most common causes of anaphylaxis. The major allergens of honeybee venom are phospholipase A2, hyaluronidase, acid phosphatase, allergen C and melitin. Phospholipase and melitin induce hemolysis, rhabdomyolysis and liver damage due to cell membrane breakdown, damage of the vascular endothelium and activation of the inflammatory response. Rhabdomyolysis has been implicated as the cause of acute renal failure in approximately 5-7% of cases. However, bee stings are a rare cause of rhabdomyolysis, and are usually associated with 50 or more stings. It has been reported that more than 250 bee stings are capable of causing death in humans. "nCase report: We report two cases of massive honeybee stings (>2000 with rhabdomyolysis, hemolysis and acute renal failure who survived with full recovery, and two cases of >500 honeybee stings who survived without significant complications.

  12. Beetle pollination and flowering rhythm of Annona coriacea Mart. (Annonaceae in Brazilian cerrado: Behavioral features of its principal pollinators.

    Directory of Open Access Journals (Sweden)

    Marilza Silva Costa

    Full Text Available 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

  13. 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

  14. How well do we understand landscape effects on pollinators and pollination services?

    Directory of Open Access Journals (Sweden)

    Blandina Felipe Viana

    2012-06-01

    Full Text Available Many studies in the past decade, mostly in temperate countries, have documented the effects of habitat loss and fragmentation on species richness, composition, and abundance and the behaviour of pollinators. Changes in landscape structure are considered to be the primary causes of the limitation of pollination services in agricultural systems. Here, we review evidence of general patterns as well as gaps in knowledge that could be used to support the development of policies for pollinator conservation and the restoration of degraded landscapes. Our results indicate a recent increase in the number of studies on the relationships between pollination processes and landscape patterns, with some key trends already being established. Many authors indicate, for example, that the spatial organization of a landscape has a great influence on the survival and dispersal capacity of many pollinators, as spatial organization affects resource availability and determines the functional connectivity of the landscape. Additionally, the shape, size and spatial arrangement of the patches of each type of natural environment, as well as the occurrence of different types of land use, can create sites with different degrees of connectivity or even barriers to movement between patches, which can deeply modify pollinator flows through the landscape and consequently the success of cross-pollination. However, there are still some gaps, such as in the knowledge of which critical values of habitat loss can lead to drastic increases in pollinator extinction rates, information that is needed to evaluate at what point plant-pollinator interactions may collapse. We also need to concentrate research effort on improving a landscape’s capacity to facilitate pollinator flow (connectivity between crops and nesting/foraging areas.

  15. Scouts behave as streakers in honeybee swarms

    Science.gov (United States)

    Greggers, Uwe; Schöning, Caspar; Degen, Jacqueline; Menzel, Randolf

    2013-08-01

    Harmonic radar tracking was used to record the flights of scout bees during takeoff and initial flight path of two honeybee swarms. One swarm remained intact and performed a full flight to a destination beyond the range of the harmonic radar, while a second swarm disintegrated within the range of the radar and most of the bees returned to the queen. The initial stretch of the full flight is characterized by accelerating speed, whereas the disintegrating swarm flew steadily at low speed. The two scouts in the swarm displaying full flight performed characteristic flight maneuvers. They flew at high speed when traveling in the direction of their destination and slowed down or returned over short stretches at low speed. Scouts in the disintegrating swarm did not exhibit the same kind of characteristic flight performance. Our data support the streaker bee hypothesis proposing that scout bees guide the swarm by traveling at high speed in the direction of the new nest site for short stretches of flight and slowing down when reversing flight direction.

  16. Risk to pollinators from the use of chlorpyrifos in the United States.

    Science.gov (United States)

    Cutler, G Christopher; Purdy, John; Giesy, John P; Solomon, Keith R

    2014-01-01

    from CPY through consumption of these food sources.Several models were also used to estimate upper-limit exposure of honey bees to CPY through consumption of water from puddles or dew. All models suggest that the risk of CPY is below the LOC for this pathway. Laboratory experiments with field-treated foliage, and semi-field and field tests with honey bees, bumble bees,and alfalfa leaf cutting bees indicate that exposure to foliage, pollen and/or nectar is hazardous to bees up to 3 d after application of CPY to a crop. Pollinators exposed to foliage, pollen or nectar after this time should be minimally affected.Several data gaps and areas of uncertainty were identified, which apply to CPYand other foliar insecticides. These primarily concern the lack of exposure and toxicological data on non-Apis pollinators. Overall, the rarity of reported bee kill incidents involving CPY indicates that compliance with the label precautions and good agricultural practice with the product is the norm in North American agriculture.Overall, we concluded that, provided label directions and good agricultural practices are followed, the use of CPY in agriculture in North America does not present an unacceptable risk to honeybees.

  17. Searching for a manageable pollinator for Acerola orchards: the solitary oil-collecting bee Centris analis (Hymenoptera: Apidae: Centridini).

    Science.gov (United States)

    Oliveira, Reisla; Schlindwein, Clemens

    2009-02-01

    Acerola (Malpighia emarginata DC; Malpighiaceae) is an important fruit crop in Brazil. Among its pollinators, Centris (Heterocentris) analis (F.) stands out due to its abundance at flowers and prompt acceptance of trap-nests. For the first time, we propose the commercial use of Centris bees as orchard pollinators. To develop protocols for rearing and management of these bees, we analyzed trap-nest acceptance, brood-cell construction, and larval diet in Acerola orchards. Although Centris species, in general, use numerous pollen host plants, females of C. analis showed remarkable flower fidelity to Acerola for pollen supply when nesting in the orchard. Such fidelity was previously expected only for floral oil collection. The ease of acceptance of trap-nests by females of C. analis, their prolonged yearly activity period, multivoltine life history, and high pollinator efficiency characterize C. analis as an excellent potentially manageable pollinator in Acerola orchards.

  18. Honeybees Produce Millimolar Concentrations of Non-Neuronal Acetylcholine for Breeding: Possible Adverse Effects of Neonicotinoids.

    Directory of Open Access Journals (Sweden)

    Ignaz Wessler

    Full Text Available The worldwide use of neonicotinoid pesticides has caused concern on account of their involvement in the decline of bee populations, which are key pollinators in most ecosystems. Here we describe a role of non-neuronal acetylcholine (ACh for breeding of Apis mellifera carnica and a so far unknown effect of neonicotinoids on non-target insects. Royal jelly or larval food are produced by the hypopharyngeal gland of nursing bees and contain unusually high ACh concentrations (4-8 mM. ACh is extremely well conserved in royal jelly or brood food because of the acidic pH of 4.0. This condition protects ACh from degradation thus ensuring delivery of intact ACh to larvae. Raising the pH to ≥5.5 and applying cholinesterase reduced the content of ACh substantially (by 75-90% in larval food. When this manipulated brood was tested in artificial larval breeding experiments, the survival rate was higher with food supplemented by 100% with ACh (6 mM than with food not supplemented with ACh. ACh release from the hypopharyngeal gland and its content in brood food declined by 80%, when honeybee colonies were exposed for 4 weeks to high concentrations of the neonicotinoids clothianidin (100 parts per billion [ppb] or thiacloprid (8,800 ppb. Under these conditions the secretory cells of the gland were markedly damaged and brood development was severely compromised. Even field-relevant low concentrations of thiacloprid (200 ppb or clothianidin (1 and 10 ppb reduced ACh level in the brood food and showed initial adverse effects on brood development. Our findings indicate a hitherto unknown target of neonicotinoids to induce adverse effects on non-neuronal ACh which should be considered when re-assessing the environmental risks of these compounds. To our knowledge this is a new biological mechanism, and we suggest that, in addition to their well documented neurotoxic effects, neonicotinoids may contribute to honeybee colony losses consecutive to a reduction of the ACh

  19. [Determination of 10-HDA in honeybee body by HPLC].

    Science.gov (United States)

    Fan, H; He, C; Han, H

    1999-05-01

    In the present work we found that in the honeybee body there exists an unsaturated fatty acid, trans-10-hydroxy-2-decenoic acid (10-HDA), which was known only to be present in royal jelly. We established the analytical method of 10-HDA in honeybee body by HPLC and simplified the extraction method of 10-HDA. In the optimum conditions the linear range of detection was 10-1,000 ng, the correlation coefficient was 0.9998, the recovery was 96.5%-99.2% and the detectable limit was 0.53 microgram/g.

  20. Mast Cells Can Enhance Resistance to Snake and Honeybee Venoms

    Science.gov (United States)

    Metz, Martin; Piliponsky, Adrian M.; Chen, Ching-Cheng; Lammel, Verena; Åbrink, Magnus; Pejler, Gunnar; Tsai, Mindy; Galli, Stephen J.

    2006-07-01

    Snake or honeybee envenomation can cause substantial morbidity and mortality, and it has been proposed that the activation of mast cells by snake or insect venoms can contribute to these effects. We show, in contrast, that mast cells can significantly reduce snake-venom-induced pathology in mice, at least in part by releasing carboxypeptidase A and possibly other proteases, which can degrade venom components. Mast cells also significantly reduced the morbidity and mortality induced by honeybee venom. These findings identify a new biological function for mast cells in enhancing resistance to the morbidity and mortality induced by animal venoms.

  1. 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

  2. Floral advertisement and the competition for pollination services.

    Science.gov (United States)

    Fishman, Michael A; Hadany, Lilach

    2015-06-01

    Flowering plants are a major component of terrestrial ecosystems, and most of them depend on animal pollinators for reproduction. Thus, the mutualism between flowering plants and their pollinators is a keystone ecological relationship in both natural and agricultural ecosystems. Though plant-pollinator interactions have received considerable amount of attention, there are still many unanswered questions. In this paper, we use methods of evolutionary game theory to investigate the co-evolution of floral advertisement and pollinator preferences Our results indicate that competition for pollination services among plant species can in some cases lead to specialization of the pollinator population to a single plant species (oligolecty). However, collecting pollen from multiple plants - at least at the population level - is evolutionarily stable under a wider parameter range. Finally, we show that, in the presence of pollinators, plants that optimize their investment in attracting vs. rewarding visiting pollinators outcompete plants that do not. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  3. Ecological stoichiometry of the honeybee: Pollen diversity and adequate species composition are needed to mitigate limitations imposed on the growth and development of bees by pollen quality.

    Science.gov (United States)

    Filipiak, Michał; Kuszewska, Karolina; Asselman, Michel; Denisow, Bożena; Stawiarz, Ernest; Woyciechowski, Michał; Weiner, January

    2017-01-01

    The least understood aspects of the nutritional needs of bees are the elemental composition of pollen and the bees' need for a stoichiometrically balanced diet containing the required proportions of nutrients. Reduced plant diversity has been proposed as an indirect factor responsible for the pollinator crisis. We suggest stoichiometric mismatch resulting from a nutritionally unbalanced diet as a potential direct factor. The concentrations and stoichiometric ratios of C, N, S, P, K, Na, Ca, Mg, Fe, Zn, Mn, and Cu were studied in the bodies of honeybees of various castes and sexes and in the nectar and pollen of various plant species. A literature review of the elemental composition of pollen was performed. We identified possible co-limitations of bee growth and development resulting mainly from the scarcity of Na, S, Cu, P and K, and possibly Zn and N, in pollen. Particular castes and sexes face specific limitations. Concentrations of potentially limiting elements in pollen revealed high taxonomic diversity. High floral diversity may be necessary to maintain populations of pollen eaters. Single-species crop plantations, even if these species are rich in nectar and pollen, might limit bee growth and development, not allowing for gathering nutrients in adequate proportions. However, particular plant species may play greater roles than others in balancing honeybee diets. Therefore, we suggest specific plant species that may (1) ensure optimal growth and production of individuals by producing pollen that is exceptionally well balanced stoichiometrically (e.g., clover) or (2) prevent growth and development of honeybees by producing pollen that is extremely unbalanced for bees (e.g., sunflower). Since pollen is generally poor in Na, this element must be supplemented using "dirty water". Nectar cannot supplement the diet with limiting elements. Stoichiometric mismatch should be considered in intervention strategies aimed at improving the nutritional base for bees.

  4. Ecological stoichiometry of the honeybee: Pollen diversity and adequate species composition are needed to mitigate limitations imposed on the growth and development of bees by pollen quality.

    Directory of Open Access Journals (Sweden)

    Michał Filipiak

    Full Text Available The least understood aspects of the nutritional needs of bees are the elemental composition of pollen and the bees' need for a stoichiometrically balanced diet containing the required proportions of nutrients. Reduced plant diversity has been proposed as an indirect factor responsible for the pollinator crisis. We suggest stoichiometric mismatch resulting from a nutritionally unbalanced diet as a potential direct factor. The concentrations and stoichiometric ratios of C, N, S, P, K, Na, Ca, Mg, Fe, Zn, Mn, and Cu were studied in the bodies of honeybees of various castes and sexes and in the nectar and pollen of various plant species. A literature review of the elemental composition of pollen was performed. We identified possible co-limitations of bee growth and development resulting mainly from the scarcity of Na, S, Cu, P and K, and possibly Zn and N, in pollen. Particular castes and sexes face specific limitations. Concentrations of potentially limiting elements in pollen revealed high taxonomic diversity. High floral diversity may be necessary to maintain populations of pollen eaters. Single-species crop plantations, even if these species are rich in nectar and pollen, might limit bee growth and development, not allowing for gathering nutrients in adequate proportions. However, particular plant species may play greater roles than others in balancing honeybee diets. Therefore, we suggest specific plant species that may (1 ensure optimal growth and production of individuals by producing pollen that is exceptionally well balanced stoichiometrically (e.g., clover or (2 prevent growth and development of honeybees by producing pollen that is extremely unbalanced for bees (e.g., sunflower. Since pollen is generally poor in Na, this element must be supplemented using "dirty water". Nectar cannot supplement the diet with limiting elements. Stoichiometric mismatch should be considered in intervention strategies aimed at improving the nutritional base

  5. Exotic plant species receive adequate pollinator service despite variable integration into plant-pollinator networks.

    Science.gov (United States)

    Thompson, Amibeth H; Knight, Tiffany M

    2018-05-01

    Both exotic and native plant species rely on insect pollinators for reproductive success, and yet few studies have evaluated whether and how exotic plant species receive services from native pollinators for successful reproduction in their introduced range. Plant species are expected to successfully reproduce in their exotic range if they have low reliance on animal pollinators or if they successfully integrate themselves into resident plant-pollinator networks. Here, we quantify the breeding system, network integration, and pollen limitation for ten focal exotic plant species in North America. Most exotic plant species relied on animal pollinators for reproduction, and these species varied in their network integration. However, plant reproduction was limited by pollen receipt for only one plant species. Our results demonstrate that even poorly integrated exotic plant species can still have high pollination service and high reproductive success. The comprehensive framework considered here provides a method to consider the contribution of plant breeding systems and the pollinator community to pollen limitation, and can be applied to future studies to provide a more synthetic understanding of the factors that determine reproductive success of exotic plant species.

  6. Point and interval estimation of pollinator importance: a study using pollination data of Silene caroliniana.

    Science.gov (United States)

    Reynolds, Richard J; Fenster, Charles B

    2008-05-01

    Pollinator importance, the product of visitation rate and pollinator effectiveness, is a descriptive parameter of the ecology and evolution of plant-pollinator interactions. Naturally, sources of its variation should be investigated, but the SE of pollinator importance has never been properly reported. Here, a Monte Carlo simulation study and a result from mathematical statistics on the variance of the product of two random variables are used to estimate the mean and confidence limits of pollinator importance for three visitor species of the wildflower, Silene caroliniana. Both methods provided similar estimates of mean pollinator importance and its interval if the sample size of the visitation and effectiveness datasets were comparatively large. These approaches allowed us to determine that bumblebee importance was significantly greater than clearwing hawkmoth, which was significantly greater than beefly. The methods could be used to statistically quantify temporal and spatial variation in pollinator importance of particular visitor species. The approaches may be extended for estimating the variance of more than two random variables. However, unless the distribution function of the resulting statistic is known, the simulation approach is preferable for calculating the parameter's confidence limits.

  7. Origem botânica de cargas de pólen de colmeias de abelhas africanizadas em Piracicaba, SP Botanic origin of pollen beehives’ loads from Africanized honeybees in Piracicaba, SP, Brazil

    Directory of Open Access Journals (Sweden)

    Anna Frida Hatsue Modro

    2011-11-01

    Full Text Available Este estudo objetivou identificar a origem botânica das cargas de pólen coletadas por abelhas africanizadas. Em Piracicaba (SP, foram instaladas, durante as quatro estações do ano, cinco colmeias de A. mellifera com um coletor de pólen frontal em cada uma. A preparação palinológica foi pelo uso de acetólise, sendo identificados e contados aproximadamente 900 grãos de pólen por amostra. A partir da composição polínica, calculou-se a riqueza, os índices de diversidade e equitabilidade. Ao longo do ano, foram encontrados 81 tipos polínicos, pertencentes a 32 famílias botânicas sendo Fabaceae, Asteraceae e Malvaceae, as famílias com maior frequência de tipos polínicos (≥5 tipos polínicos, e Myrtaceae, a família com dois tipos polínicos (Eucalyptus sp. e Myrcia sp. entre os nove mais frequentes nas amostras (>10%. A maior riqueza de tipos polínicos foi no verão e a maior diversidade e equitabilidade, na primavera. Fabaceae, Asteraceae, Malvaceae e Myrtaceae são as famílias botânicas mais importantes como fontes poliníferas em Piracicaba - SP.This study aimed to identify the botanic origin of pollen loads collected by Africanized honeybees. In Piracicaba (SP, during four seasons of the year, five honeybee colonies were installed with a frontal pollen collector in each one. The palinological preparation was done by the use of acetolysis and identified and counted approximately 900 pollen grains per sample. From the pollinic composition, the richness, diversity indexes and equitability were calculated. Throughout the year, 81 pollinic types were found, belonging to 32 botanic families, being Fabaceae, Asteraceae and Malvaceae the ones with the biggest frequency of pollinic types (≥5 pollinic types and, Myrtaceae, the family with two pollinic types (Eucalyptus sp. and Myrcia sp., among the nine most common types in the samples (> 10%. The biggest richness of pollinic types was during summer, and the biggest diversity and

  8. Pollination ecology of the New Zealand alpine flora

    OpenAIRE

    Bischoff, Mascha

    2008-01-01

    The interactions between flowers and the insects that pollinate them have fascinated scientists for more than 200 years. The last century saw the establishment of the fundamental concept of pollination syndromes which allows classification of flowers according to the agents that pollinate them demonstrating specialisation and co-evolution of plants and pollinators. This concept has recently been questioned and the contrary, ubiquitous generalisation and chance have been proposed to be the dri...

  9. 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

  10. 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

  11. 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.

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

    African Journals Online (AJOL)

    enoh

    2012-04-05

    Apr 5, 2012 ... flowers (Bohart, 1972). Pollinators ... and crops. The inadequacies have arisen from habitat fragmentation ... Pollen colour. Availability ... due to its geographical importance. ... of pollinators varies with the topographic change. ..... G.F.J. Eagles & S.D. Price (Eds). ... pollinator in Vegetable Seed Production.

  13. The pollination of Canavalia virosa by Xylocopid and Magachilid bees

    Directory of Open Access Journals (Sweden)

    C. H. Stirton

    1977-11-01

    Full Text Available The floral morphology of Canavalia virosa (Roxb. Wight & Arn. is discussed in relation to pollination by Xylocopa flavorufa De Greer and  Megachile combusta Sm. It was found that the relationship between size of flower and bee influenced the type of pollinating strategy and its success. Bees smaller than M. combusta proved ineffective pollinators.

  14. Generalised pollination systems for three invasive milkweeds in Australia.

    Science.gov (United States)

    Ward, M; Johnson, S D

    2013-05-01

    Because most plants require pollinator visits for seed production, the ability of an introduced plant species to establish pollinator relationships in a new ecosystem may have a central role in determining its success or failure as an invader. We investigated the pollination ecology of three milkweed species - Asclepias curassavica, Gomphocarpus fruticosus and G. physocarpus - in their invaded range in southeast Queensland, Australia. The complex floral morphology of milkweeds has often been interpreted as a general trend towards specialised pollination requirements. Based on this interpretation, invasion by milkweeds contradicts the expectation than plant species with specialised pollination systems are less likely to become invasive that those with more generalised pollination requirements. However, observations of flower visitors in natural populations of the three study species revealed that their pollination systems are essentially specialised at the taxonomic level of the order, but generalised at the species level. Specifically, pollinators of the two Gomphocarpus species included various species of Hymenoptera (particularly vespid wasps), while pollinators of A. curassavica were primarily Lepidoptera (particularly nymphalid butterflies). Pollinators of all three species are rewarded with copious amounts of highly concentrated nectar. It is likely that successful invasion by these three milkweed species is attributable, at least in part, to their generalised pollinator requirements. The results of this study are discussed in terms of how data from the native range may be useful in predicting pollination success of species in a new environment. © 2012 German Botanical Society and The Royal Botanical Society of the Netherlands.

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

    African Journals Online (AJOL)

    Francis

    of wild and crop plants are fully or partially dependent on pollinators for their ... Agricultural intensification leads to loss and fragmentation of natural pollinator ..... 0.4, pollination 3.1, pest control of native herbivores 4.5, and 'recreation' [food for ... Ehrlich PR & Michener CD (2004) Economic value of tropical forest to coffee.

  16. Morphofunctional Experience-Dependent Plasticity in the Honeybee Brain

    Science.gov (United States)

    Andrione, Mara; Timberlake, Benjamin F.; Vallortigara, Giorgio; Antolini, Renzo; Haase, Albrecht

    2017-01-01

    Repeated or prolonged exposure to an odorant without any positive or negative reinforcement produces experience-dependent plasticity, which results in habituation and latent inhibition. In the honeybee ("Apis mellifera"), it has been demonstrated that, even if the absolute neural representation of an odor in the primary olfactory center,…

  17. Abscisic acid enhances cold tolerance in honeybee larvae

    Science.gov (United States)

    Sturla, Laura; Guida, Lucrezia; Vigliarolo, Tiziana; Maggi, Matías; Eguaras, Martín; Zocchi, Elena; Lamattina, Lorenzo

    2017-01-01

    The natural composition of nutrients present in food is a key factor determining the immune function and stress responses in the honeybee (Apis mellifera). We previously demonstrated that a supplement of abscisic acid (ABA), a natural component of nectar, pollen, and honey, increases honeybee colony survival overwinter. Here we further explored the role of ABA in in vitro-reared larvae exposed to low temperatures. Four-day-old larvae (L4) exposed to 25°C for 3 days showed lower survival rates and delayed development compared to individuals growing at a standard temperature (34°C). Cold-stressed larvae maintained higher levels of ABA for longer than do larvae reared at 34°C, suggesting a biological significance for ABA. Larvae fed with an ABA-supplemented diet completely prevent the low survival rate due to cold stress and accelerate adult emergence. ABA modulates the expression of genes involved in metabolic adjustments and stress responses: Hexamerin 70b, Insulin Receptor Substrate, Vitellogenin, and Heat Shock Proteins 70. AmLANCL2, the honeybee ABA receptor, is also regulated by cold stress and ABA. These results support a role for ABA increasing the tolerance of honeybee larvae to low temperatures through priming effects. PMID:28381619

  18. Stimulating natural supersedure of honeybee queens, Apis mellifera

    NARCIS (Netherlands)

    Hendriksma, H.P.; Calis, J.N.M.; Boot, W.J.

    2004-01-01

    When a honeybee queen starts to fail, she is often superseded by a young queen that takes over reproduction inside the colony. Natural supersedure in winter leads to an unfertilised young queen and colony loss. To reduce these losses we tried to stimulate supersedure of queens earlier in the season.

  19. Genetic structure of Balearic honeybee populations based on microsatellite polymorphism

    Directory of Open Access Journals (Sweden)

    Moritz Robin FA

    2003-05-01

    Full Text Available Abstract The genetic variation of honeybee colonies collected in 22 localities on the Balearic Islands (Spain was analysed using eight polymorphic microsatellite loci. Previous studies have demonstrated that these colonies belong either to the African or west European evolutionary lineages. These populations display low variability estimated from both the number of alleles and heterozygosity values, as expected for the honeybee island populations. Although genetic differentiation within the islands is low, significant heterozygote deficiency is present, indicating a subpopulation genetic structure. According to the genetic differentiation test, the honeybee populations of the Balearic Islands cluster into two groups: Gimnesias (Mallorca and Menorca and Pitiusas (Ibiza and Formentera, which agrees with the biogeography postulated for this archipelago. The phylogenetic analysis suggests an Iberian origin of the Balearic honeybees, thus confirming the postulated evolutionary scenario for Apis mellifera in the Mediterranean basin. The microsatellite data from Formentera, Ibiza and Menorca show that ancestral populations are threatened by queen importations, indicating that adequate conservation measures should be developed for protecting Balearic bees.

  20. Wax combs mediate nestmate recognition by guard honeybees

    DEFF Research Database (Denmark)

    D'Ettorre, Patrizia; Wenseleers, Tom; Dawson, Jenny

    2006-01-01

    Research has shown that the wax combs are important in the acquisition of colony odour in the honeybee, Apis mellifera. However, many of these studies were conducted in the laboratory or under artificial conditions. We investigated the role of the wax combs in nestmate recognition in the natural...

  1. Immune and clinical response to honeybee venom in beekeepers

    Directory of Open Access Journals (Sweden)

    Jan Matysiak

    2016-03-01

    The differences in the immune response to a bee sting between the beekeepers and individuals not exposed to bees were probably due to the high exposure of the beekeepers to honeybee venom allergens. This may suggest a different approach to the bee venom allergy diagnostic tests in this occupational group.

  2. Abscisic acid enhances cold tolerance in honeybee larvae.

    Science.gov (United States)

    Ramirez, Leonor; Negri, Pedro; Sturla, Laura; Guida, Lucrezia; Vigliarolo, Tiziana; Maggi, Matías; Eguaras, Martín; Zocchi, Elena; Lamattina, Lorenzo

    2017-04-12

    The natural composition of nutrients present in food is a key factor determining the immune function and stress responses in the honeybee ( Apis mellifera ). We previously demonstrated that a supplement of abscisic acid (ABA), a natural component of nectar, pollen, and honey, increases honeybee colony survival overwinter. Here we further explored the role of ABA in in vitro -reared larvae exposed to low temperatures. Four-day-old larvae (L4) exposed to 25°C for 3 days showed lower survival rates and delayed development compared to individuals growing at a standard temperature (34°C). Cold-stressed larvae maintained higher levels of ABA for longer than do larvae reared at 34°C, suggesting a biological significance for ABA. Larvae fed with an ABA-supplemented diet completely prevent the low survival rate due to cold stress and accelerate adult emergence. ABA modulates the expression of genes involved in metabolic adjustments and stress responses: Hexamerin 70b, Insulin Receptor Substrate, Vitellogenin , and Heat Shock Proteins 70. AmLANCL2, the honeybee ABA receptor, is also regulated by cold stress and ABA. These results support a role for ABA increasing the tolerance of honeybee larvae to low temperatures through priming effects. © 2017 The Author(s).

  3. Studies on the life cycle and morphometrics of honeybees, Apis ...

    African Journals Online (AJOL)

    The life cycle of the honeybee, Apis mellifera adansonii, was studied in mangrove area by monitoring the developmental stages and morphology of the castes. It was observed that the fate of the eggs were predetermined at the onset leading to drones, queens or workers. It was also established that the three different castes ...

  4. Genetic variation in natural honeybee populations, Apis mellifera capensis

    Science.gov (United States)

    Hepburn, Randall; Neumann, Peter; Radloff, Sarah E.

    2004-09-01

    Genetic variation in honeybee, Apis mellifera, populations can be considerably influenced by breeding and commercial introductions, especially in areas with abundant beekeeping. However, in southern Africa apiculture is based on the capture of wild swarms, and queen rearing is virtually absent. Moreover, the introduction of European subspecies constantly failed in the Cape region. We therefore hypothesize a low human impact on genetic variation in populations of Cape honeybees, Apis mellifera capensis. A novel solution to studying genetic variation in honeybee populations based on thelytokous worker reproduction is applied to test this hypothesis. Environmental effects on metrical morphological characters of the phenotype are separated to obtain a genetic residual component. The genetic residuals are then re-calculated as coefficients of genetic variation. Characters measured included hair length on the abdomen, width and length of wax plate, and three wing angles. The data show for the first time that genetic variation in Cape honeybee populations is independent of beekeeping density and probably reflects naturally occurring processes such as gene flow due to topographic and climatic variation on a microscale.

  5. Nursing protects honeybee larvae from secondary metabolites of pollen.

    Science.gov (United States)

    Lucchetti, Matteo A; Kilchenmann, Verena; Glauser, Gaetan; Praz, Christophe; Kast, Christina

    2018-03-28

    The pollen of many plants contains toxic secondary compounds, sometimes in concentrations higher than those found in the flowers or leaves. The ecological significance of these compounds remains unclear, and their impact on bees is largely unexplored. Here, we studied the impact of pyrrolizidine alkaloids (PAs) found in the pollen of Echium vulgare on honeybee adults and larvae. Echimidine, a PA present in E. vulgare pollen, was isolated and added to the honeybee diets in order to perform toxicity bioassays. While adult bees showed relatively high tolerance to PAs, larvae were much more sensitive. In contrast to other bees, the honeybee larval diet typically contains only traces of pollen and consists predominantly of hypopharyngeal and mandibular secretions produced by nurse bees, which feed on large quantities of pollen-containing bee bread. We quantified the transfer of PAs to nursing secretions produced by bees that had previously consumed bee bread supplemented with PAs. The PA concentration in these secretions was reduced by three orders of magnitude as compared to the PA content in the nurse diet and was well below the toxicity threshold for larvae. Our results suggest that larval nursing protects honeybee larvae from the toxic effect of secondary metabolites of pollen. © 2018 The Authors.

  6. Sperm use economy of honeybee (Apis mellifera) queens

    DEFF Research Database (Denmark)

    Baer, Boris; Collins, Jason; Maalaps, Kristiina

    2016-01-01

    the fecundity and longevity of queens and therefore colony fitness. We quantified the number of sperm that honeybee (Apis mellifera) queens use to fertilize eggs. We examined sperm use in naturally mated queens of different ages and in queens artificially inseminated with different volumes of semen. We found...

  7. Biophysics of the subgenual organ of the honeybee, Apis mellifera

    DEFF Research Database (Denmark)

    Kilpinen, Ole; Storm, Jesper

    1997-01-01

    The subgenual organ of the honeybee (Apis mellifera) is suspended in a haemolymph channel in the tibia of each leg. When the leg is accelerated, inertia causes the haemolymph (and the subgenual organ) to lag behind the movement of the rest of the leg. The magnitude of this phase lag determines...

  8. Nursing protects honeybee larvae from secondary metabolites of pollen

    Science.gov (United States)

    Lucchetti, Matteo A.; Kilchenmann, Verena; Glauser, Gaetan; Praz, Christophe

    2018-01-01

    The pollen of many plants contains toxic secondary compounds, sometimes in concentrations higher than those found in the flowers or leaves. The ecological significance of these compounds remains unclear, and their impact on bees is largely unexplored. Here, we studied the impact of pyrrolizidine alkaloids (PAs) found in the pollen of Echium vulgare on honeybee adults and larvae. Echimidine, a PA present in E. vulgare pollen, was isolated and added to the honeybee diets in order to perform toxicity bioassays. While adult bees showed relatively high tolerance to PAs, larvae were much more sensitive. In contrast to other bees, the honeybee larval diet typically contains only traces of pollen and consists predominantly of hypopharyngeal and mandibular secretions produced by nurse bees, which feed on large quantities of pollen-containing bee bread. We quantified the transfer of PAs to nursing secretions produced by bees that had previously consumed bee bread supplemented with PAs. The PA concentration in these secretions was reduced by three orders of magnitude as compared to the PA content in the nurse diet and was well below the toxicity threshold for larvae. Our results suggest that larval nursing protects honeybee larvae from the toxic effect of secondary metabolites of pollen. PMID:29563265

  9. Sleep Deprivation affects Extinction but Not Acquisition Memory in Honeybees

    Science.gov (United States)

    Hussaini, Syed Abid; Bogusch, Lisa; Landgraf, Tim; Menzel, Randolf

    2009-01-01

    Sleep-like behavior has been studied in honeybees before, but the relationship between sleep and memory formation has not been explored. Here we describe a new approach to address the question if sleep in bees, like in other animals, improves memory consolidation. Restrained bees were observed by a web camera, and their antennal activities were…

  10. Transcriptome differences in the hypopharyngeal gland between Western Honeybees (Apis mellifera) and Eastern Honeybees (Apis cerana).

    Science.gov (United States)

    Liu, Hao; Wang, Zi-Long; Tian, Liu-Qing; Qin, Qiu-Hong; Wu, Xiao-Bo; Yan, Wei-Yu; Zeng, Zhi-Jiang

    2014-08-30

    Apis mellifera and Apis cerana are two sibling species of Apidae. Apis cerana is adept at collecting sporadic nectar in mountain and forest region and exhibits stiffer hardiness and acarid resistance as a result of natural selection, whereas Apis mellifera has the advantage of producing royal jelly. To identify differentially expressed genes (DEGs) that affect the development of hypopharyngeal gland (HG) and/or the secretion of royal jelly between these two honeybee species, we performed a digital gene expression (DGE) analysis of the HGs of these two species at three developmental stages (newly emerged worker, nurse and forager). Twelve DGE-tag libraries were constructed and sequenced using the total RNA extracted from the HGs of newly emerged workers, nurses, and foragers of Apis mellifera and Apis cerana. Finally, a total of 1482 genes in Apis mellifera and 1313 in Apis cerana were found to exhibit an expression difference among the three developmental stages. A total of 1417 DEGs were identified between these two species. Of these, 623, 1072, and 462 genes showed an expression difference at the newly emerged worker, nurse, and forager stages, respectively. The nurse stage exhibited the highest number of DEGs between these two species and most of these were found to be up-regulated in Apis mellifera. These results suggest that the higher yield of royal jelly in Apis mellifera may be due to the higher expression level of these DEGs. In this study, we investigated the DEGs between the HGs of two sibling honeybee species (Apis mellifera and Apis cerana). Our results indicated that the gene expression difference was associated with the difference in the royal jelly yield between these two species. These results provide an important clue for clarifying the mechanisms underlying hypopharyngeal gland development and the production of royal jelly.

  11. Functional characterization of transmembrane adenylyl cyclases from the honeybee brain.

    Science.gov (United States)

    Balfanz, Sabine; Ehling, Petra; Wachten, Sebastian; Jordan, Nadine; Erber, Joachim; Mujagic, Samir; Baumann, Arnd

    2012-06-01

    The second messenger cAMP has a pivotal role in animals' physiology and behavior. Intracellular concentrations of cAMP are balanced by cAMP-synthesizing adenylyl cyclases (ACs) and cAMP-cleaving phosphodiesterases. Knowledge about ACs in the honeybee (Apis mellifera) is rather limited and only an ortholog of the vertebrate AC3 isoform has been functionally characterized, so far. Employing bioinformatics and functional expression we characterized two additional honeybee genes encoding membrane-bound (tm)ACs. The proteins were designated AmAC2t and AmAC8. Unlike the common structure of tmACs, AmAC2t lacks the first transmembrane domain. Despite this unusual topography, AmAC2t-activity could be stimulated by norepinephrine and NKH477 with EC(50s) of 0.07 μM and 3 μM. Both ligands stimulated AmAC8 with EC(50s) of 0.24 μM and 3.1 μM. In brain cryosections, intensive staining of mushroom bodies was observed with specific antibodies against AmAC8, an expression pattern highly reminiscent of the Drosophila rutabaga AC. In a current release of the honeybee genome database we identified three additional tmAC- and one soluble AC-encoding gene. These results suggest that (1) the AC-gene family in honeybees is comparably large as in other species, and (2) based on the restricted expression of AmAC8 in mushroom bodies, this enzyme might serve important functions in honeybee behavior. Copyright © 2012 Elsevier Ltd. All rights reserved.

  12. 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 ...

  13. Native Honey Bees Outperform Adventive Honey Bees in Increasing Pyrus bretschneideri (Rosales: Rosaceae) Pollination.

    Science.gov (United States)

    Gemeda, Tolera Kumsa; Shao, Youquan; Wu, Wenqin; Yang, Huipeng; Huang, Jiaxing; Wu, Jie

    2017-12-05

    The foraging behavior of different bee species is a key factor influencing the pollination efficiency of different crops. Most pear species exhibit full self-incompatibility and thus depend entirely on cross-pollination. However, as little is known about the pear visitation preferences of native Apis cerana (Fabricius; Hymenoptera: Apidae) and adventive Apis mellifera (L.; Hymenoptera: Apidae) in China. A comparative analysis was performed to explore the pear-foraging differences of these species under the natural conditions of pear growing areas. The results show significant variability in the pollen-gathering tendency of these honey bees. Compared to A. mellifera, A. cerana begins foraging at an earlier time of day and gathers a larger amount of pollen in the morning. Based on pollen collection data, A. mellifera shows variable preferences: vigorously foraging on pear on the first day of observation but collecting pollen from non-target floral resources on other experimental days. Conversely, A. cerana persists in pear pollen collection, without shifting preference to other competitive flowers. Therefore, A. cerana outperforms adventive A. mellifera with regard to pear pollen collection under natural conditions, which may lead to increased pear pollination. This study supports arguments in favor of further multiplication and maintenance of A. cerana for pear and other native crop pollination. Moreover, it is essential to develop alternative pollination management techniques to utilize A. mellifera for pear pollination. © The Author(s) 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  14. Big bees do a better job: intraspecific size variation influences pollination effectiveness

    Directory of Open Access Journals (Sweden)

    Pat Willmer

    2014-09-01

    Full Text Available 1. Bumblebees (Bombus spp. are efficient pollinators of many flowering plants, yet the pollen deposition performance of individual bees has not been investigated. Worker bumblebees exhibit large intraspecific and intra-nest size variation, in contrast with other eusocial bees; and their size influences collection and deposition of pollen grains. 2. Laboratory studies with B. terrestris workers and Vinca minor flowers showed that pollination effectiveness PE, as measured from pollen grains deposited on stigmas in single visits (SVD, was significantly positively related to bee size; larger bees deposited more grains, while the smallest individuals, with proportionally shorter tongues, were unable to collect or deposit pollen in these flowers. Individuals did not increase their pollen deposition over time, so handling experience does not influence SVD in Vinca minor. 3. Field studies using Geranium sanguineum and Echium vulgare, and multiple visiting species, confirmed that individual size affects SVD. All bumblebee species showed positive SVD/size effects, though even the smallest individuals did deposit pollen. Apis with its limited size variation showed no such detectable effect when visiting Geranium flowers. Two abundant hoverfly species also showed size effects, particularly when feeding for nectar on Echium. 4. Mean size of foragers also varied diurnally, with larger individuals active earlier and later, so that pollination effectiveness varies through a day; flowers routinely pollinated by bees may best be served by early morning dehiscence and visits from larger individuals. 5. Thus, while there are well-documented species-level variations in pollination effectiveness, the fine-scale individual differences between foragers should also be taken into account when assessing the reproductive outputs of biotically-pollinated plants.

  15. Ecological intensification to mitigate impacts of conventional intensive land use on pollinators and pollination

    OpenAIRE

    Kovács-Hostyánszki, Anikó; Espíndola, Anahí; Vanbergen, Adam J.; Settele, Josef; Kremen, Claire; Dicks, Lynn V.

    2017-01-01

    Worldwide, human appropriation of ecosystems is disrupting plant–pollinator communities and pollination function through habitat conversion and landscape homogenisation. Conversion to agriculture is destroying and degrading semi-natural ecosystems while conventional land-use intensification (e.g. industrial management of large-scale monocultures with high chemical inputs) homogenises landscape structure and quality. Together, these anthropogenic processes reduce the connectivity of population...

  16. In-Depth N-Glycosylation Reveals Species-Specific Modifications and Functions of the Royal Jelly Protein from Western (Apis mellifera) and Eastern Honeybees (Apis cerana).

    Science.gov (United States)

    Feng, Mao; Fang, Yu; Han, Bin; Xu, Xiang; Fan, Pei; Hao, Yue; Qi, Yuping; Hu, Han; Huo, Xinmei; Meng, Lifeng; Wu, Bin; Li, Jianke

    2015-12-04

    Royal jelly (RJ), secreted by honeybee workers, plays diverse roles as nutrients and defense agents for honeybee biology and human health. Despite being reported to be glycoproteins, the glycosylation characterization and functionality of RJ proteins in different honeybee species are largely unknown. An in-depth N-glycoproteome analysis and functional assay of RJ produced by Apis mellifera lingustica (Aml) and Apis cerana cerana (Acc) were conducted. RJ produced by Aml yielded 80 nonredundant N-glycoproteins carrying 190 glycosites, of which 23 novel proteins harboring 35 glycosites were identified. For Acc, all 43 proteins glycosylated at 138 glycosites were reported for the first time. Proteins with distinct N-glycoproteomic characteristics in terms of glycoprotein species, number of N-glycosylated sites, glycosylation motif, abundance level of glycoproteins, and N-glycosites were observed in this two RJ samples. The fact that the low inhibitory efficiency of N-glycosylated major royal jelly protein 2 (MRJP2) against Paenibacillus larvae (P. larvae) and the absence of antibacterial related glycosylated apidaecin, hymenoptaecin, and peritrophic matrix in the Aml RJ compared to Acc reveal the mechanism for why the Aml larvae are susceptible to P. larvae, the causative agent of a fatal brood disease (American foulbrood, AFB). The observed antihypertension activity of N-glycosylated MRJP1 in two RJ samples and a stronger activity found in Acc than in Aml reveal that specific RJ protein and modification are potentially useful for the treatment of hypertensive disease for humans. Our data gain novel understanding that the western and eastern bees have evolved species-specific strategies of glycosylation to fine-tune protein activity for optimizing molecular function as nutrients and immune agents for the good of honeybee and influence on the health promoting activity for human as well. This serves as a valuable resource for the targeted probing of the biological

  17. Exploring Nectar Biology To Learn about Pollinators.

    Science.gov (United States)

    LaBare, Kelly M.; Broyles, Steven B.; Klotz, R. Lawrence

    2000-01-01

    Discusses the importance of studying nectar biology. Describes how to extract nectar from various flowers, measure nectar volume, determine sugar concentration, and determine caloric value per nectar sample. These data are then related to hummingbird energetics to determine how many flowers are required to supply the pollinator with its caloric…

  18. Varroa destructor mite in Africanized honeybee colonies Apis mellifera L. under royal jelly or honey production

    Directory of Open Access Journals (Sweden)

    Pedro da Rosa Santos

    2015-08-01

    Full Text Available This study evaluated the level of invasion of Varroa mite into worker brood cells, the infestation rate on adult worker honeybees, total and effective reproduction rates of the mite in Africanized honeybee colonies under royal jelly or honey production. Invasion and infestation rates were not statistically different between honeybee colonies producing honey or royal jelly and the averages for these parameters were 5.79 and 8.54%, respectively. Colonies producing honey presented a higher (p < 0.05 total and effective reproduction of Varroa than colonies producing royal jelly. There was a negative correlation between levels of invasion and infestation with minimum external temperature, relative humidity and rainfall. The variables month and season influenced the development of the mite, but rates were low and within the range normally found in Brazil for Africanized honeybee colonies, which confirm the greater resistance of these honeybees to Varroa destructor than European honeybees.

  19. Direct and Indirect Influence of Non-Native Neighbours on Pollination and Fruit Production of a Native Plant.

    Directory of Open Access Journals (Sweden)

    Ana Montero-Castaño

    Full Text Available Entomophilous non-native plants can directly affect the pollination and reproductive success of native plant species and also indirectly, by altering the composition and abundance of floral resources in the invaded community. Separating direct from indirect effects is critical for understanding the mechanisms underlying the impacts of non-native species on recipient communities.Our aims are: (a to explore both the direct effect of the non-native Hedysarum coronarium and its indirect effect, mediated by the alteration of floral diversity, on the pollinator visitation rate and fructification of the native Leopoldia comosa and (b to distinguish whether the effects of the non-native species were due to its floral display or to its vegetative interactions.We conducted field observations within a flower removal experimental setup (i.e. non-native species present, absent and with its inflorescences removed at the neighbourhood scale.Our study illustrates the complexity of mechanisms involved in the impacts of non-native species on native species. Overall, Hedysarum increased pollinator visitation rates to Leopoldia target plants as a result of direct and indirect effects acting in the same direction. Due to its floral display, Hedysarum exerted a direct magnet effect attracting visits to native target plants, especially those made by the honeybee. Indirectly, Hedysarum also increased the visitation rate of native target plants. Due to the competition for resources mediated by its vegetative parts, it decreased floral diversity in the neighbourhoods, which was negatively related to the visitation rate to native target plants. Hedysarum overall also increased the fructification of Leopoldia target plants, even though such an increase was the result of other indirect effects compensating for the observed negative indirect effect mediated by the decrease of floral diversity.

  20. The nectar spur is not only a simple specialization for long-proboscid pollinators.

    Science.gov (United States)

    Vlašánková, Anna; Padyšáková, Eliška; Bartoš, Michael; Mengual, Ximo; Janečková, Petra; Janeček, Štěpán

    2017-09-01

    Since the time of Darwin, biologists have considered the floral nectar spur to be an adaptation representing a high degree of plant specialization. Nevertheless, some researchers suggest that nature is more complex and that even morphologically specialized plants attract a wide spectrum of visitors. We observed visitors on Impatiens burtonii (Balsaminaceae) and measured the depth of the proboscis insertion into the spur, the distance of the nectar surface from the spur entrance and the visitor's effectiveness. The hoverfly Melanostoma sp., with the shortest proboscis, was most active early in the morning and fed on pollen and nectar near the spur entrance. The honeybee Apis mellifera and the hoverfly Rhingia mecyana were the most frequent visitors before and after noon, respectively. Although R. mecyana, the only visitor able to reach the end of the spur, was the most frequent, it did not deposit the largest number of pollen grains per visit. Nectar spurs may function as complex structures allowing pollination by both short- and long-proboscid visitors and separating their spatial and temporal niches. Spurred plants should be considered as more generalized and exposed to more diverse selection pressures than previously believed. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

  1. Evaluation of the defensive behavior of two honeybee ecotypes using a laboratory test

    Directory of Open Access Journals (Sweden)

    Cecilia Andere

    2002-01-01

    Full Text Available Honeybee defensive behavior is a useful selection criterion, especially in areas with Africanized honeybees (Apis mellifera L. In all genetic improvement programs the selected characters must be measured with precision, and because of this we evaluated a metabolic method for testing honeybee defensive behavior in the laboratory for its usefulness in distinguishing between honeybee ecotypes and selecting honeybees based on their level of defensive responses. Ten honeybee colonies were used, five having been produced by feral queens from a subtropical region supposedly colonized by Africanized honeybees and five by queens from a temperate region apparently colonized by European honeybees. We evaluate honeybee defensive behavior using a metabolic test based on oxygen consumption after stimulation with an alarm pheromone, measuring the time to the first response, time to maximum oxygen consumption, duration of activity, oxygen consumption at first response, maximum oxygen consumption and total oxygen consumption, colonies being ranked according to the values obtained for each variable. Significant (p < 0.05 differences were detected between ecotypes for each variable but for all variables the highest rankings were obtained for colonies of subtropical origin, which had faster and more intense responses. All variables were highly associated (p < 0.05. Total oxygen consumption was the best indicator of metabolic activity for defensive behavior because it combined oxygen consumption and the length of the response. This laboratory method may be useful for evaluating the defensive behavior of honey bees in genetic programs designed to select less defensive bees.

  2. Fire promotes pollinator visitation: implications for ameliorating declines of pollination services.

    Directory of Open Access Journals (Sweden)

    Michael E Van Nuland

    Full Text Available Pollinators serve critical roles for the functioning of terrestrial ecosystems, and have an estimated annual value of over $150 billion for global agriculture. Mounting evidence from agricultural systems reveals that pollinators are declining in many regions of the world, and with a lack of information on whether pollinator communities in natural systems are following similar trends, identifying factors which support pollinator visitation and services are important for ameliorating the effects of the current global pollinator crisis. We investigated how fire affects resource structure and how that variation influences floral pollinator communities by comparing burn versus control treatments in a southeastern USA old-field system. We hypothesized and found a positive relationship between fire and plant density of a native forb, Verbesina alternifolia, as well as a significant difference in floral visitation of V. alternifolia between burn and control treatments. V. alternifolia density was 44% greater and floral visitation was 54% greater in burned treatments relative to control sites. When the density of V. alternifolia was experimentally reduced in the burn sites to equivalent densities observed in control sites, floral visitation in burned sites declined to rates found in control sites. Our results indicate that plant density is a proximal mechanism by which an imposed fire regime can indirectly impact floral visitation, suggesting its usefulness as a tool for management of pollination services. Although concerns surround the negative impacts of management, indirect positive effects may provide an important direction to explore for managing future ecological and conservation issues. Studies examining the interaction among resource concentration, plant apparency, and how fire affects the evolutionary consequences of altered patterns of floral visitation are overdue.

  3. Bumblebees (Bombus terrestris) and honeybees (Apis mellifera) prefer similar colours of higher spectral purity over trained colours.

    Science.gov (United States)

    Rohde, Katja; Papiorek, Sarah; Lunau, Klaus

    2013-03-01

    Differences in the concentration of pigments as well as their composition and spatial arrangement cause intraspecific variation in the spectral signature of flowers. Known colour preferences and requirements for flower-constant foraging bees predict different responses to colour variability. In experimental settings, we simulated small variations of unicoloured petals and variations in the spatial arrangement of colours within tricoloured petals using artificial flowers and studied their impact on the colour choices of bumblebees and honeybees. Workers were trained to artificial flowers of a given colour and then given the simultaneous choice between three test colours: either the training colour, one colour of lower and one of higher spectral purity, or the training colour, one colour of lower and one of higher dominant wavelength; in all cases the perceptual contrast between the training colour and the additional test colours was similarly small. Bees preferred artificial test flowers which resembled the training colour with the exception that they preferred test colours with higher spectral purity over trained colours. Testing the behaviour of bees at artificial flowers displaying a centripetal or centrifugal arrangement of three equally sized colours with small differences in spectral purity, bees did not prefer any type of artificial flowers, but preferentially choose the most spectrally pure area for the first antenna contact at both types of artificial flowers. Our results indicate that innate preferences for flower colours of high spectral purity in pollinators might exert selective pressure on the evolution of flower colours.

  4. Low doses of neonicotinoid pesticides in food rewards impair short-term olfactory memory in foraging-age honeybees.

    Science.gov (United States)

    Wright, Geraldine A; Softley, Samantha; Earnshaw, Helen

    2015-10-19

    Neonicotinoids are often applied as systemic seed treatments to crops and have reported negative impact on pollinators when they appear in floral nectar and pollen. Recently, we found that bees in a two-choice assay prefer to consume solutions containing field-relevant doses of the neonicotinoid pesticides, imidacloprid (IMD) and thiamethoxam (TMX), to sucrose alone. This suggests that neonicotinoids enhance the rewarding properties of sucrose and that low, acute doses could improve learning and memory in bees. To test this, we trained foraging-age honeybees to learn to associate floral scent with a reward containing nectar-relevant concentrations of IMD and TMX and tested their short (STM) and long-term (LTM) olfactory memories. Contrary to our predictions, we found that none of the solutions enhanced the rate of olfactory learning and some of them impaired it. In particular, the effect of 10 nM IMD was observed by the second conditioning trial and persisted 24 h later. In most other groups, exposure to IMD and TMX affected STM but not LTM. Our data show that negative impacts of low doses of IMD and TMX do not require long-term exposure and suggest that impacts of neonicotinoids on olfaction are greater than their effects on rewarding memories.

  5. Dynamics of an ant-plant-pollinator model

    Science.gov (United States)

    Wang, Yuanshi; DeAngelis, Donald L.; Nathaniel Holland, J.

    2015-03-01

    In this paper, we consider plant-pollinator-ant systems in which plant-pollinator interaction and plant-ant interaction are both mutualistic, but there also exists interference of pollinators by ants. The plant-pollinator interaction can be described by a Beddington-DeAngelis formula, so we extend the formula to characterize plant-pollinator mutualisms, including the interference by ants, and form a plant-pollinator-ant model. Using dynamical systems theory, we show uniform persistence of the model. Moreover, we demonstrate conditions under which boundary equilibria are globally asymptotically stable. The dynamics exhibit mechanisms by which the three species could coexist when ants interfere with pollinators. We define a threshold in ant interference. When ant interference is strong, it can drive plant-pollinator mutualisms to extinction. Furthermore, if the ants depend on pollination mutualism for their persistence, then sufficiently strong ant interference could lead to their own extinction as well. Yet, when ant interference is weak, plant-ant and plant-pollinator mutualisms can promote the persistence of one another.

  6. Pollinator effectiveness varies with experimental shifts in flowering time.

    Science.gov (United States)

    Rafferty, Nicole E; Ives, Anthony R

    2012-04-01

    The earlier flowering times exhibited by many plant species are a conspicuous sign of climate change. Altered phenologies have caused concern that species could suffer population declines if they flower at times when effective pollinators are unavailable. For two perennial wildflowers, Tradescantia ohiensis and Asclepias incarnata, we used an experimental approach to explore how changing phenology affects the taxonomic composition of the pollinator assemblage and the effectiveness of individual pollinator taxa. After finding in the previous year that fruit set varied with flowering time, we manipulated flowering onset in greenhouses, placed plants in the field over the span of five weeks, and measured pollinator effectiveness as the number of seeds produced after a single visit to a flower. The average effectiveness of pollinators and the expected rates of pollination success were lower for plants of both species flowering earlier than for plants flowering at historical times, suggesting there could be reproductive costs to earlier flowering. Whereas for A. incarnata, differences in average seed set among weeks were due primarily to changes in the composition of the pollinator assemblage, the differences for T. ohiensis were driven by the combined effects of compositional changes and increases over time in the effectiveness of some pollinator taxa. Both species face the possibility of temporal mismatch between the availability of the most effective pollinators and the onset of flowering, and changes in the effectiveness of individual pollinator taxa through time may add an unexpected element to the reproductive consequences of such mismatches.

  7. Ecology and evolution of plant–pollinator interactions

    Science.gov (United States)

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

    2009-01-01

    Background 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. Scope 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. PMID:19482881

  8. 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.

  9. 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.

  10. Immunosuppression in Honeybee Queens by the Neonicotinoids Thiacloprid and Clothianidin.

    Science.gov (United States)

    Brandt, Annely; Grikscheit, Katharina; Siede, Reinhold; Grosse, Robert; Meixner, Marina Doris; Büchler, Ralph

    2017-07-05

    Queen health is crucial to colony survival of honeybees, since reproduction and colony growth rely solely on the queen. Queen failure is considered a relevant cause of colony losses, yet few data exist concerning effects of environmental stressors on queens. Here we demonstrate for the first time that exposure to field-realistic concentrations of neonicotinoid pesticides can severely affect the immunocompetence of queens of western honeybees (Apis mellifera L.). In young queens exposed to thiacloprid (200 µg/l or 2000 µg/l) or clothianidin (10 µg/l or 50 µg/l), the total hemocyte number and the proportion of active, differentiated hemocytes was significantly reduced. Moreover, functional aspects of the immune defence namely the wound healing/melanisation response, as well as the antimicrobial activity of the hemolymph were impaired. Our results demonstrate that neonicotinoid insecticides can negatively affect the immunocompetence of queens, possibly leading to an impaired disease resistance capacity.

  11. A comparison of controlled self-pollination and open pollination results based on maize grain quality

    Directory of Open Access Journals (Sweden)

    Hanna Sulewska

    2014-05-01

    Full Text Available Maize (Zea mays L. grain endosperm is triploid (3n, of which 2n come from the male (transferred by pollen and only 1n from the female plant, thus a major impact of the male form can be expected on grain quality parameters. A good example of this relationship is the phenomenon of xenia. The aim of this study was to determine the effect of pollen on grain quality. The field experiment was conducted in 2011; seeds were harvested from eight cultivars: Bosman, Blask, Tur, Kozak, Bielik, Smok, SMH 220 and Kresowiak, derived from free pollination and controlled self-pollination of maize. Analyses of nutrient contents and starch content in the grain were conducted in the laboratory. In addition, 1000 grain weight and the hectoliter weight of all grain samples were recorded. The results confirmed differences in grain quality of maize hybrids obtained by self-pollination and by open pollination. Grain of maize plants obtained by open-pollination was characterised by higher contents of N-free extract and starch, and lower protein content. Undertaking further studies on this subject may indicate specific recommendations for agricultural practice, such as mixtures of hybrids with good combining abilities, which will contribute to improved grain quality without additional costs.

  12. 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.

  13. 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.

  14. Detection of Illicit Drugs by Trained Honeybees (Apis mellifera.

    Directory of Open Access Journals (Sweden)

    Matthias Schott

    Full Text Available Illegal drugs exacerbate global social challenges such as substance addiction, mental health issues and violent crime. Police and customs officials often rely on specially-trained sniffer dogs, which act as sensitive biological detectors to find concealed illegal drugs. However, the dog "alert" is no longer sufficient evidence to allow a search without a warrant or additional probable cause because cannabis has been legalized in two US states and is decriminalized in many others. Retraining dogs to recognize a narrower spectrum of drugs is difficult and training new dogs is time consuming, yet there are no analytical devices with the portability and sensitivity necessary to detect substance-specific chemical signatures. This means there is currently no substitute for sniffer dogs. Here we describe an insect screening procedure showing that the western honeybee (Apis mellifera can sense volatiles associated with pure samples of heroin and cocaine. We developed a portable electroantennographic device for the on-site measurement of volatile perception by these insects, and found a positive correlation between honeybee antennal responses and the concentration of specific drugs in test samples. Furthermore, we tested the ability of honeybees to learn the scent of heroin and trained them to show a reliable behavioral response in the presence of a highly-diluted scent of pure heroin. Trained honeybees could therefore be used to complement or replace the role of sniffer dogs as part of an automated drug detection system. Insects are highly sensitive to volatile compounds and provide an untapped resource for the development of biosensors. Automated conditioning as presented in this study could be developed as a platform for the practical detection of illicit drugs using insect-based sensors.

  15. Protection of carniolan bee - preserve breed or race of honeybee?

    OpenAIRE

    Božič, Janko

    2015-01-01

    Slovenia protects authentic breed of carniolan bee based on zootechnical legislation. Different varieties of honeybee around the Earth are usually described with the term races and not breeds. Foundations for such nomenclature are in evolution of bee races with natural selection without considerable influence of the men. Acceptance of carniolan bee as a race determines environmental-protection approach in preservation of authentic carniolan bee population. Slovenia is locus typicus of the rac...

  16. Detection of Illicit Drugs by Trained Honeybees (Apis mellifera).

    Science.gov (United States)

    Schott, Matthias; Klein, Birgit; Vilcinskas, Andreas

    2015-01-01

    Illegal drugs exacerbate global social challenges such as substance addiction, mental health issues and violent crime. Police and customs officials often rely on specially-trained sniffer dogs, which act as sensitive biological detectors to find concealed illegal drugs. However, the dog "alert" is no longer sufficient evidence to allow a search without a warrant or additional probable cause because cannabis has been legalized in two US states and is decriminalized in many others. Retraining dogs to recognize a narrower spectrum of drugs is difficult and training new dogs is time consuming, yet there are no analytical devices with the portability and sensitivity necessary to detect substance-specific chemical signatures. This means there is currently no substitute for sniffer dogs. Here we describe an insect screening procedure showing that the western honeybee (Apis mellifera) can sense volatiles associated with pure samples of heroin and cocaine. We developed a portable electroantennographic device for the on-site measurement of volatile perception by these insects, and found a positive correlation between honeybee antennal responses and the concentration of specific drugs in test samples. Furthermore, we tested the ability of honeybees to learn the scent of heroin and trained them to show a reliable behavioral response in the presence of a highly-diluted scent of pure heroin. Trained honeybees could therefore be used to complement or replace the role of sniffer dogs as part of an automated drug detection system. Insects are highly sensitive to volatile compounds and provide an untapped resource for the development of biosensors. Automated conditioning as presented in this study could be developed as a platform for the practical detection of illicit drugs using insect-based sensors.

  17. Ocellar structure and neural innervation in the honeybee

    Directory of Open Access Journals (Sweden)

    Yu-Shan eHung

    2014-02-01

    Full Text Available Honeybees have a visual system composed of three ocelli (simple eyes located on the top of the head, in addition to two large compound eyes. Although experiments have been conducted to investigate the role of the ocelli within the visual system, their optical characteristics, and function remain controversial. In this study, we created three-dimensional (3-D reconstructions of the honeybee ocelli, conducted optical measurements and filled ocellar descending neurons to assist in determining the role of ocelli in honeybees. In both the median and lateral ocelli, the ocellar retinas can be divided into dorsal and ventral parts. Using the 3-D model we were able to assess the viewing angles of the retinas. The dorsal retinas view the horizon while the ventral retinas view the sky, suggesting quite different roles in attitude control. We used the hanging drop technique to assess the spatial resolution of each retina. The lateral ocelli have considerably higher spatial resolution compared to the median ocellus. Moreover, in both types of ocellus the dorsal retina has a higher spatial resolution than the ventral retina. In addition, we established which ocellar retinas provide the input to five pairs of large ocellar descending neurons. We found that four of the neuron pairs had their dendritic fields in the dorsal retinas of the lateral ocelli, while the fifth had fine dendrites in the ventral retina. One of the neuron pairs also sent very fine dendrites into the border region between the dorsal and ventral retinas of the median ocellus.

  18. Impact of bifenthrin on honeybees and Culex quinquefasciatus.

    Science.gov (United States)

    Qualls, Whitney A; Xue, Rui-De; Zhong, He

    2010-06-01

    The impact of bifenthrin on honeybees, Apis mellifera (Hymenoptera: Apidae) was evaluated in both laboratory and semifield assays. Ten serial dilutions of bifenthrin and an acetone control using the bottle bioassay protocol were used in the laboratory to determine killing time after 15-, 30-, and 60-min honeybee exposure. Both dose and exposure time significantly affected honeybee mortality (df = 6, F = 10.9, P Bifenthrin was applied at 9.7 ml/liter, 19.5 ml/liter, and 29.5 ml/liter of water to common landscape vegetation, Melampodium paludosum Melanie (show star) and Duranta erecta L. (golden dewdrop); a water control was also used. Bee mortality was significantly higher (P < 0.05, df = 2, F = 20.8) at 29.5 ml/liter compared to the mortality at 19.5-ml/liter and 9.7-ml/liter application rates after 24-h exposure to the treated vegetation. Mortality of Culex quinquefasciatus exposed to treated vegetation was significantly (P < 0.05, df = 10, F = 114) different by week and by application rate.

  19. Parasitic Cape honeybee workers, Apis mellifera capensis, evade policing

    Science.gov (United States)

    Martin, Stephen J.; Beekman, Madeleine; Wossler, Theresa C.; Ratnieks, Francis L. W.

    2002-01-01

    Relocation of the Cape honeybee, Apis mellifera capensis, by bee-keepers from southern to northern South Africa in 1990 has caused widespread death of managed African honeybee, A. m. scutellata, colonies. Apis mellifera capensis worker bees are able to lay diploid, female eggs without mating by means of automictic thelytoky (meiosis followed by fusion of two meiotic products to restore egg diploidy), whereas workers of other honeybee subspecies are able to lay only haploid, male eggs. The A. m. capensis workers, which are parasitizing and killing A. m. scutellata colonies in northern South Africa, are the asexual offspring of a single, original worker in which the small amount of genetic variation observed is due to crossing over during meiosis (P. Kryger, personal communication). Here we elucidate two principal mechanisms underlying this parasitism. Parasitic A. m. capensis workers activate their ovaries in host colonies that have a queen present (queenright colonies), and they lay eggs that evade being killed by other workers (worker policing)-the normal fate of worker-laid eggs in colonies with a queen. This unique parasitism by workers is an instance in which a society is unable to control the selfish actions of its members.

  20. Modelling the spread of American foulbrood in honeybees

    Science.gov (United States)

    Datta, Samik; Bull, James C.; Budge, Giles E.; Keeling, Matt J.

    2013-01-01

    We investigate the spread of American foulbrood (AFB), a disease caused by the bacterium Paenibacillus larvae, that affects bees and can be extremely damaging to beehives. Our dataset comes from an inspection period carried out during an AFB epidemic of honeybee colonies on the island of Jersey during the summer of 2010. The data include the number of hives of honeybees, location and owner of honeybee apiaries across the island. We use a spatial SIR model with an underlying owner network to simulate the epidemic and characterize the epidemic using a Markov chain Monte Carlo (MCMC) scheme to determine model parameters and infection times (including undetected ‘occult’ infections). Likely methods of infection spread can be inferred from the analysis, with both distance- and owner-based transmissions being found to contribute to the spread of AFB. The results of the MCMC are corroborated by simulating the epidemic using a stochastic SIR model, resulting in aggregate levels of infection that are comparable to the data. We use this stochastic SIR model to simulate the impact of different control strategies on controlling the epidemic. It is found that earlier inspections result in smaller epidemics and a higher likelihood of AFB extinction. PMID:24026473

  1. Therapeutic Properties of Bioactive Compounds from Different Honeybee Products.

    Science.gov (United States)

    Cornara, Laura; Biagi, Marco; Xiao, Jianbo; Burlando, Bruno

    2017-01-01

    Honeybees produce honey, royal jelly, propolis, bee venom, bee pollen, and beeswax, which potentially benefit to humans due to the bioactives in them. Clinical standardization of these products is hindered by chemical variability depending on honeybee and botanical sources, but different molecules have been isolated and pharmacologically characterized. Major honey bioactives include phenolics, methylglyoxal, royal jelly proteins (MRJPs), and oligosaccharides. In royal jelly there are antimicrobial jelleins and royalisin peptides, MRJPs, and hydroxy-decenoic acid derivatives, notably 10-hydroxy-2-decenoic acid (10-HDA), with antimicrobial, anti-inflammatory, immunomodulatory, neuromodulatory, metabolic syndrome preventing, and anti-aging activities. Propolis contains caffeic acid phenethyl ester and artepillin C, specific of Brazilian propolis, with antiviral, immunomodulatory, anti-inflammatory and anticancer effects. Bee venom consists of toxic peptides like pain-inducing melittin, SK channel blocking apamin, and allergenic phospholipase A2. Bee pollen is vitaminic, contains antioxidant and anti-inflammatory plant phenolics, as well as antiatherosclerotic, antidiabetic, and hypoglycemic flavonoids, unsaturated fatty acids, and sterols. Beeswax is widely used in cosmetics and makeup. Given the importance of drug discovery from natural sources, this review is aimed at providing an exhaustive screening of the bioactive compounds detected in honeybee products and of their curative or adverse biological effects.

  2. Mating flights select for symmetry in honeybee drones ( Apis mellifera)

    Science.gov (United States)

    Jaffé, Rodolfo; Moritz, Robin F. A.

    2010-03-01

    Males of the honeybee ( Apis mellifera) fly to specific drone congregation areas (DCAs), which virgin queens visit in order to mate. From the thousands of drones that are reared in a single colony, only very few succeed in copulating with a queen, and therefore, a strong selection is expected to act on adult drones during their mating flights. In consequence, the gathering of drones at DCAs may serve as an indirect mate selection mechanism, assuring that queens only mate with those individuals having a better flight ability and a higher responsiveness to the queen’s visual and chemical cues. Here, we tested this idea relying on wing fluctuating asymmetry (FA) as a measure of phenotypic quality. By recapturing marked drones at a natural DCA and comparing their size and FA with a control sample of drones collected at their maternal hives, we were able to detect any selection on wing size and wing FA occurring during the mating flights. Although we found no solid evidence for selection on wing size, wing FA was found to be significantly lower in the drones collected at the DCA than in those collected at the hives. Our results demonstrate the action of selection during drone mating flights for the first time, showing that developmental stability can influence the mating ability of honeybee drones. We therefore conclude that selection during honeybee drone mating flights may confer some fitness advantages to the queens.

  3. Proteomic analysis of honeybee worker (Apis mellifera hypopharyngeal gland development

    Directory of Open Access Journals (Sweden)

    Li Jianke

    2009-12-01

    Full Text Available Abstract Background Hypopharyngeal glands (HG of honeybee workers play an important role in honeybee nutrition and caste differentiation. Previous research mainly focused on age-dependent morphological, physiological, biochemical and genomic characters of the HG. Here proteomics and biochemical network analysis were used to follow protein changes during the HG development. Results A total of 87, 76, 85, 74, 71, and 55 proteins were unambiguously identified on day 1, 3, 6, 12, 15 and 20, respectively. These proteins were major royal jelly proteins (MRJPs, metabolism of carbohydrates, lipids and proteins, cytoskeleton, development regulation, antioxidant, molecule transporter, regulation of transcription/translation, proteins with folding functions. The most interesting is that MRJP's that have been detected in the HG of the newly emerged worker bees. The MRJP's expression is at peak level from 6-12 days, was validated by western blot analysis of MRJP1, 2 and 3. Moreover, 35 key node proteins were found in the biochemical networks of the HG. Conclusions HG secretes RJ at peak level within 6-12 days, but the worker bee can secrete royal jelly (RJ since birth, which is a new finding. Several key node proteins play an important role in the biochemical networks of the developing HG. This provides us some target proteins when genetically manipulating honeybees.

  4. Therapeutic Properties of Bioactive Compounds from Different Honeybee Products

    Directory of Open Access Journals (Sweden)

    Laura Cornara

    2017-06-01

    Full Text Available Honeybees produce honey, royal jelly, propolis, bee venom, bee pollen, and beeswax, which potentially benefit to humans due to the bioactives in them. Clinical standardization of these products is hindered by chemical variability depending on honeybee and botanical sources, but different molecules have been isolated and pharmacologically characterized. Major honey bioactives include phenolics, methylglyoxal, royal jelly proteins (MRJPs, and oligosaccharides. In royal jelly there are antimicrobial jelleins and royalisin peptides, MRJPs, and hydroxy-decenoic acid derivatives, notably 10-hydroxy-2-decenoic acid (10-HDA, with antimicrobial, anti-inflammatory, immunomodulatory, neuromodulatory, metabolic syndrome preventing, and anti-aging activities. Propolis contains caffeic acid phenethyl ester and artepillin C, specific of Brazilian propolis, with antiviral, immunomodulatory, anti-inflammatory and anticancer effects. Bee venom consists of toxic peptides like pain-inducing melittin, SK channel blocking apamin, and allergenic phospholipase A2. Bee pollen is vitaminic, contains antioxidant and anti-inflammatory plant phenolics, as well as antiatherosclerotic, antidiabetic, and hypoglycemic flavonoids, unsaturated fatty acids, and sterols. Beeswax is widely used in cosmetics and makeup. Given the importance of drug discovery from natural sources, this review is aimed at providing an exhaustive screening of the bioactive compounds detected in honeybee products and of their curative or adverse biological effects.

  5. Mating flights select for symmetry in honeybee drones (Apis mellifera).

    Science.gov (United States)

    Jaffé, Rodolfo; Moritz, Robin F A

    2010-03-01

    Males of the honeybee (Apis mellifera) fly to specific drone congregation areas (DCAs), which virgin queens visit in order to mate. From the thousands of drones that are reared in a single colony, only very few succeed in copulating with a queen, and therefore, a strong selection is expected to act on adult drones during their mating flights. In consequence, the gathering of drones at DCAs may serve as an indirect mate selection mechanism, assuring that queens only mate with those individuals having a better flight ability and a higher responsiveness to the queen's visual and chemical cues. Here, we tested this idea relying on wing fluctuating asymmetry (FA) as a measure of phenotypic quality. By recapturing marked drones at a natural DCA and comparing their size and FA with a control sample of drones collected at their maternal hives, we were able to detect any selection on wing size and wing FA occurring during the mating flights. Although we found no solid evidence for selection on wing size, wing FA was found to be significantly lower in the drones collected at the DCA than in those collected at the hives. Our results demonstrate the action of selection during drone mating flights for the first time, showing that developmental stability can influence the mating ability of honeybee drones. We therefore conclude that selection during honeybee drone mating flights may confer some fitness advantages to the queens.

  6. Western honeybee drones and workers (Apis mellifera ligustica) have different olfactory mechanisms than eastern honeybees (Apis cerana cerana).

    Science.gov (United States)

    Woltedji, Dereje; Song, Feifei; Zhang, Lan; Gala, Alemayehu; Han, Bin; Feng, Mao; Fang, Yu; Li, Jianke

    2012-09-07

    The honeybees Apis mellifera ligustica (Aml) and Apis cerana cerana (Acc) are two different western and eastern bee species that evolved in distinct ecologies and developed specific antennal olfactory systems for their survival. Knowledge of how their antennal olfactory systems function in regards to the success of each respective bee species is scarce. We compared the antennal morphology and proteome between respective sexually mature drones and foraging workers of both species using a scanning electron microscope, two-dimensional electrophoresis, mass spectrometry, bioinformatics, and quantitative real-time polymerase chain reaction. Despite the general similarities in antennal morphology of the drone and worker bees between the two species, a total of 106 and 100 proteins altered their expression in the drones' and the workers' antennae, respectively. This suggests that the differences in the olfactory function of each respective bee are supported by the change of their proteome. Of the 106 proteins that altered their expression in the drones, 72 (68%) and 34 (32%) were overexpressed in the drones of Aml and Acc, respectively. The antennae of the Aml drones were built up by the highly expressed proteins that were involved in carbohydrate metabolism and energy production, molecular transporters, antioxidation, and fatty acid metabolism in contrast to the Acc drones. This is believed to enhance the antennal olfactory functions of the Aml drones as compared to the Acc drones during their mating flight. Likewise, of the 100 proteins with expression changes between the worker bees of the two species, 67% were expressed in higher levels in the antennae of Aml worker contrasting to 33% in the Acc worker. The overall higher expressions of proteins related to carbohydrate metabolism and energy production, molecular transporters, and antioxidation in the Aml workers compared with the Acc workers indicate the Aml workers require more antennal proteins for their olfactory

  7. 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.

  8. Predicting Spatial Distribution of Key Honeybee Pests in Kenya Using Remotely Sensed and Bioclimatic Variables: Key Honeybee Pests Distribution Models

    Directory of Open Access Journals (Sweden)

    David M. Makori

    2017-02-01

    Full Text Available Bee keeping is indispensable to global food production. It is an alternate income source, especially in rural underdeveloped African settlements, and an important forest conservation incentive. However, dwindling honeybee colonies around the world are attributed to pests and diseases whose spatial distribution and influences are not well established. In this study, we used remotely sensed data to improve the reliability of pest ecological niche (EN models to attain reliable pest distribution maps. Occurrence data on four pests (Aethina tumida, Galleria mellonella, Oplostomus haroldi and Varroa destructor were collected from apiaries within four main agro-ecological regions responsible for over 80% of Kenya’s bee keeping. Africlim bioclimatic and derived normalized difference vegetation index (NDVI variables were used to model their ecological niches using Maximum Entropy (MaxEnt. Combined precipitation variables had a high positive logit influence on all remotely sensed and biotic models’ performance. Remotely sensed vegetation variables had a substantial effect on the model, contributing up to 40.8% for G. mellonella and regions with high rainfall seasonality were predicted to be high-risk areas. Projections (to 2055 indicated that, with the current climate change trend, these regions will experience increased honeybee pest risk. We conclude that honeybee pests could be modelled using bioclimatic data and remotely sensed variables in MaxEnt. Although the bioclimatic data were most relevant in all model results, incorporating vegetation seasonality variables to improve mapping the ‘actual’ habitat of key honeybee pests and to identify risk and containment zones needs to be further investigated.

  9. The Standardization of the Honeybee Colonies Evaluation Methodology, with Application in Honeybee Breeding Programs, in Romanian Conditions

    OpenAIRE

    Eliza Cauia; Adrian Siceanu; Silvia Patruica; Marian Bura; Agripina Sapcaliu; Maria Magdici

    2010-01-01

    It is well known that breeding is based on phenotypic and behavioural performance assessed at the level of each honeybee colony. By selection, the genes responsible for the desired characters have to be favoured, by evaluation and classification of all colonies involved in a breeding program. Generally, in the beekeeping practice, the most applied method of selection is the mass selection regarding the main objective- honey production. Some more elaborated programs use selection simultaneous ...

  10. Importance of pollinators in changing landscapes for world crops

    OpenAIRE

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

    2006-01-01

    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, glo...

  11. Pollination ecosystem services in South African agricultural systems

    OpenAIRE

    Annalie Melin; Mathieu Rouget; Jeremy J. Midgley; John S. Donaldson

    2014-01-01

    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,...

  12. Evaluating Pollination Deficits in Pumpkin Production in New York

    OpenAIRE

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

    2017-01-01

    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 c...

  13. Defining the Insect Pollinator Community Found in Iowa Corn and Soybean Fields: Implications for Pollinator Conservation.

    Science.gov (United States)

    Wheelock, M J; Rey, K P; O'Neal, M E

    2016-10-01

    Although corn (Zea mays L.) and soybeans (Glycine max L.) do not require pollination, they offer floral resources used by insect pollinators. We asked if a similar community of insect pollinators visits these crops in central Iowa, a landscape dominated by corn and soybean production. We used modified pan traps (i.e., bee bowls) in both corn and soybean fields during anthesis and used nonmetric multidimensional scaling (NMS) to compare the communities found in the two crops. Summed across both crops, 6,704 individual insects were captured representing at least 60 species, morphospecies, or higher-level taxa. Thirty-four species were collected in both crops, 19 collected only in corn and seven were collected only in soybean. The most abundant taxa were Lasioglossum [Dialictus] spp., Agapostemon virescens Cresson, Melissodes bimaculata (Lepeletier), and Toxomerus marginatus (Say), which accounted for 65% of the insect pollinators collected from both crops. Although social bees (Apis mellifera L. and Bombus spp.) were found in both crops, they accounted for only 0.5% of all insects captured. The NMS analysis revealed a shared community of pollinators composed of mostly solitary, ground nesting bees. Many of these species have been found in other crop fields throughout North America. Although corn and soybean are grown in landscapes that are often highly disturbed, these data suggest that a community of pollinators can persist within them. We suggest approaches to conserving this community based on partnering with activities that aim to lessen the environmental impact of annual crop production. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  14. 76 FR 54072 - Emergency Assistance for Livestock, Honeybees, and Farm-Raised Fish Program, Livestock Indemnity...

    Science.gov (United States)

    2011-08-31

    ... for Livestock, Honeybees, and Farm-Raised Fish Program, Livestock Indemnity Program, and General... clarifying amendments and corrections to the regulations for the Emergency Assistance for Livestock, Honeybees, and Farm-Raised Fish Program (ELAP) and the Livestock Indemnity Program (LIP) to clarify when...

  15. A selective sweep in a microsporidian parasite Nosema-tolerant honeybee population, Apis mellifera

    DEFF Research Database (Denmark)

    Huang, Q.; Lattorff, H. M. G.; Kryger, P.

    2014-01-01

    Nosema is a microsporidian parasite of the honeybee, which infects the epithelial cells of the gut. In Denmark, honeybee colonies have been selectively bred for the absence of Nosema over decades, resulting in a breeding line that is tolerant toward Nosema infections. As the tolerance toward the ...

  16. 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.

  17. Collapse of a pollination web in small conservation areas.

    Science.gov (United States)

    Pauw, Anton

    2007-07-01

    A suspected global decline in pollinators has heightened interest in their ecological significance. In a worst-case scenario, the decline of generalist pollinators is predicted to trigger cascades of linked declines among the multiple specialist plant species to which they are linked, but this has not been documented. I studied a portion of a pollination web involving a generalist pollinator, the oil-collecting bee Rediviva peringueyi, and a community of oil-secreting plants. Across 27 established conservation areas located in the Cape Floral Region, I found substantial variation in the bees' occurrence in relation to soil type and the successional stage of the vegetation. Anthropogenic declines were detectable against this background of naturally occurring variation: R. peringueyi was absent from small conservation areas (urban matrix. In the absence of the bee, seed set failed in six specialist plant species that are pollinated only by R. peringueyi but remained high in a pollination generalist, which had replacement pollinators. The findings are consistent with theoretical predictions of the importance of generalist pollinators in maintaining the structure of pollination webs.

  18. 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.

  19. 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.

  20. Pollinators' mating rendezvous and the evolution of floral advertisement.

    Science.gov (United States)

    Fishman, Michael A; Hadany, Lilach

    2013-01-07

    Successful cross-fertilization in plant species that rely on animal pollinators depends not just on the number of pollinator visits, but also on these visits' duration. Furthermore, in non-deceptive pollination, a visit's duration depends on the magnitude of the reward provided to the pollinator. Accordingly, plants that rely on biotic pollination have to partition their investment in cross-fertilization assurance between attracting pollinator visits - advertisement, and rewarding visitors to assure that the visit is of productive duration. Here we analyze these processes by a combination of optimality methods and game theoretical modeling. Our results indicate that the optimality in such allocation of resources depends on the types of reward offered to the pollinators. More precisely, we show that plants that offer both food reward and mating rendezvous to pollinators will evolve to allocate a higher proportion of their cross-fertilization assurance budget to advertisement than plants that offer only food reward. That is, our results indicate that pollinators' mating habits may play a role in floral evolution. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. 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....

  2. Competition for pollinators and intra-communal spectral dissimilarity of flowers

    NARCIS (Netherlands)

    van der Kooi, C. J.; Pen, I.; Staal, M.; Stavenga, D. G.; Elzenga, J. T. M.

    Competition for pollinators occurs when, in a community of flowering plants, several simultaneously flowering plant species depend on the same pollinator. Competition for pollinators increases interspecific pollen transfer rates, thereby reducing the number of viable offspring. In order to decrease

  3. Dose-dependent effects of nectar alkaloids in a montane plant-pollinator community

    Science.gov (United States)

    Although secondary metabolites are prevalent in floral nectar, the ecological consequences for pollinators and pollination remain relatively unexplored. While often deterrent to pollinators at high concentrations, secondary metabolite concentrations in nectar tend to be much lower than secondary met...

  4. Evaluation of common methods for sampling invertebrate pollinator assemblages: net sampling out-perform pan traps.

    Directory of Open Access Journals (Sweden)

    Tony J Popic

    Full Text Available Methods for sampling ecological assemblages strive to be efficient, repeatable, and representative. Unknowingly, common methods may be limited in terms of revealing species function and so of less value for comparative studies. The global decline in pollination services has stimulated surveys of flower-visiting invertebrates, using pan traps and net sampling. We explore the relative merits of these two methods in terms of species discovery, quantifying abundance, function, and composition, and responses of species to changing floral resources. Using a spatially-nested design we sampled across a 5000 km(2 area of arid grasslands, including 432 hours of net sampling and 1296 pan trap-days, between June 2010 and July 2011. Net sampling yielded 22% more species and 30% higher abundance than pan traps, and better reflected the spatio-temporal variation of floral resources. Species composition differed significantly between methods; from 436 total species, 25% were sampled by both methods, 50% only by nets, and the remaining 25% only by pans. Apart from being less comprehensive, if pan traps do not sample flower-visitors, the link to pollination is questionable. By contrast, net sampling functionally linked species to pollination through behavioural observations of flower-visitation interaction frequency. Netted specimens are also necessary for evidence of pollen transport. Benefits of net-based sampling outweighed minor differences in overall sampling effort. As pan traps and net sampling methods are not equivalent for sampling invertebrate-flower interactions, we recommend net sampling of invertebrate pollinator assemblages, especially if datasets are intended to document declines in pollination and guide measures to retain this important ecosystem service.

  5. Evaluation of common methods for sampling invertebrate pollinator assemblages: net sampling out-perform pan traps.

    Science.gov (United States)

    Popic, Tony J; Davila, Yvonne C; Wardle, Glenda M

    2013-01-01

    Methods for sampling ecological assemblages strive to be efficient, repeatable, and representative. Unknowingly, common methods may be limited in terms of revealing species function and so of less value for comparative studies. The global decline in pollination services has stimulated surveys of flower-visiting invertebrates, using pan traps and net sampling. We explore the relative merits of these two methods in terms of species discovery, quantifying abundance, function, and composition, and responses of species to changing floral resources. Using a spatially-nested design we sampled across a 5000 km(2) area of arid grasslands, including 432 hours of net sampling and 1296 pan trap-days, between June 2010 and July 2011. Net sampling yielded 22% more species and 30% higher abundance than pan traps, and better reflected the spatio-temporal variation of floral resources. Species composition differed significantly between methods; from 436 total species, 25% were sampled by both methods, 50% only by nets, and the remaining 25% only by pans. Apart from being less comprehensive, if pan traps do not sample flower-visitors, the link to pollination is questionable. By contrast, net sampling functionally linked species to pollination through behavioural observations of flower-visitation interaction frequency. Netted specimens are also necessary for evidence of pollen transport. Benefits of net-based sampling outweighed minor differences in overall sampling effort. As pan traps and net sampling methods are not equivalent for sampling invertebrate-flower interactions, we recommend net sampling of invertebrate pollinator assemblages, especially if datasets are intended to document declines in pollination and guide measures to retain this important ecosystem service.

  6. An ultraviolet floral polymorphism associated with life history drives pollinator discrimination in Mimulus guttatus.

    Science.gov (United States)

    Peterson, Megan L; Miller, Timothy J; Kay, Kathleen M

    2015-03-01

    • Ultraviolet (UV) floral patterns are common in angiosperms and mediate pollinator attraction, efficiency, and constancy. UV patterns may vary within species, yet are cryptic to human observers. Thus, few studies have explicitly described the distribution or ecological significance of intraspecific variation in UV floral patterning. Here, we describe the geographic distribution and pattern of inheritance of a UV polymorphism in the model plant species Mimulus guttatus (Phrymaceae). We then test whether naturally occurring UV phenotypes influence pollinator interactions within M. guttatus.• We document UV patterns in 18 annual and 19 perennial populations and test whether UV pattern is associated with life history. To examine the pattern of inheritance, we conducted crosses within and between UV phenotypes. Finally, we tested whether bee pollinators discriminate among naturally occurring UV phenotypes in two settings: wild bee communities and captive Bombus impatiens.• Within M. guttatus, perennial populations exhibit a small bulls-eye pattern, whereas a bilaterally symmetric runway pattern occurs mainly in annual populations. Inheritance of UV patterning is consistent with a single-locus Mendelian model in which the runway phenotype is dominant. Bee pollinators discriminate against unfamiliar UV patterns in both natural and controlled settings.• We describe a widespread UV polymorphism associated with life history divergence within Mimulus guttatus. UV pattern influences pollinator visitation and should be considered when estimating reproductive barriers between life history ecotypes. This work develops a new system to investigate the ecology and evolution of UV floral patterning in a species with extensive genomic resources. © 2015 Botanical Society of America, Inc.

  7. Physical interaction between floral specialist bees Ptilothrix bombiformis (Cresson) (Hymenoptera: Apidae) enhances pollination of hibiscus (section Trionum: Malvaceae)

    Science.gov (United States)

    Specialist bees, those species with narrow dietary niches, rely on a few related species of floral hosts for food. Accordingly, specialists are thought of as being more efficient pollinators than are generalists. There is growing evidence, however, that this is not true in all cases. For example, we...

  8. Organic Farming Favours Insect-Pollinated over Non-Insect Pollinated Forbs in Meadows and Wheat Fields

    Science.gov (United States)

    Batáry, Péter; Sutcliffe, Laura; Dormann, Carsten F.; Tscharntke, Teja

    2013-01-01

    The aim of this study was to determine the relative effects of landscape-scale management intensity, local management intensity and edge effect on diversity patterns of insect-pollinated vs. non-insect pollinated forbs in meadows and wheat fields. Nine landscapes were selected differing in percent intensively used agricultural area (IAA), each with a pair of organic and conventional winter wheat fields and a pair of organic and conventional meadows. Within fields, forbs were surveyed at the edge and in the interior. Both diversity and cover of forbs were positively affected by organic management in meadows and wheat fields. This effect, however, differed significantly between pollination types for species richness in both agroecosystem types (i.e. wheat fields and meadows) and for cover in meadows. Thus, we show for the first time in a comprehensive analysis that insect-pollinated plants benefit more from organic management than non-insect pollinated plants regardless of agroecosystem type and landscape complexity. These benefits were more pronounced in meadows than wheat fields. Finally, the community composition of insect-pollinated and non-insect-pollinated forbs differed considerably between management types. In summary, our findings in both agroecosystem types indicate that organic management generally supports a higher species richness and cover of insect-pollinated plants, which is likely to be favourable for the density and diversity of bees and other pollinators. PMID:23382979

  9. Organic farming favours insect-pollinated over non-insect pollinated forbs in meadows and wheat fields.

    Science.gov (United States)

    Batáry, Péter; Sutcliffe, Laura; Dormann, Carsten F; Tscharntke, Teja

    2013-01-01

    The aim of this study was to determine the relative effects of landscape-scale management intensity, local management intensity and edge effect on diversity patterns of insect-pollinated vs. non-insect pollinated forbs in meadows and wheat fields. Nine landscapes were selected differing in percent intensively used agricultural area (IAA), each with a pair of organic and conventional winter wheat fields and a pair of organic and conventional meadows. Within fields, forbs were surveyed at the edge and in the interior. Both diversity and cover of forbs were positively affected by organic management in meadows and wheat fields. This effect, however, differed significantly between pollination types for species richness in both agroecosystem types (i.e. wheat fields and meadows) and for cover in meadows. Thus, we show for the first time in a comprehensive analysis that insect-pollinated plants benefit more from organic management than non-insect pollinated plants regardless of agroecosystem type and landscape complexity. These benefits were more pronounced in meadows than wheat fields. Finally, the community composition of insect-pollinated and non-insect-pollinated forbs differed considerably between management types. In summary, our findings in both agroecosystem types indicate that organic management generally supports a higher species richness and cover of insect-pollinated plants, which is likely to be favourable for the density and diversity of bees and other pollinators.

  10. 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.

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

    Science.gov (United States)

    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.

  12. 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

  13. 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

  14. Plants and colour: Flowers and pollination

    Science.gov (United States)

    Miller, Renee; Owens, Simon J.; Rørslett, Bjørn

    2011-03-01

    While there is a range of colours found in plants the predominant colour is green. Pigments in plants have several roles e.g. photosynthesis and signalling. If colour is to be used as a signal then it must stand out from green. However, one should be aware that there are also coloured compounds where we have not yet fully investigated the role of colour in their functions—they may have roles in, for example, defence or heat exchange. In this paper, we will describe the basic chemistry of the major pigments found in plants and especially floral pigments. We will then discuss their locations in parts of the flower (such as sepals, petals, pollen and nectar), the cells in which they are found and their sub-cellular locations. Floral pigments have a large role to play in pollination of flowers by animals. They can and are modified in many ways during the development of flowers in nature, for example, at emergence and post-pollination. There are a range of biochemical mechanisms of colour change both within flowers and in isolated pigments. Some of the factors influencing colour are temperature, co-pigments, pH, metals, sugars, anthocyanin stacking and cell shape. There is a renewed interest in analysing floral pigments and how they are modified partly because of advances in recombinant DNA technologies, but also because of pollinators and their significance to biodiversity and for evolutionary studies. There is continued strong interest from the horticultural industry for the introduction of new colours e.g. the blue rose and for the exploitation of natural dyes. Funding in this area may impact future research in a potentially beneficial way but it must not deflect us from science-based conservation.

  15. 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...

  16. Pollinator species richness: Are the declines slowing down?

    Directory of Open Access Journals (Sweden)

    Tom J. M. Van Dooren

    2016-09-01

    Full Text Available Changes in pollinator abundances and diversity are of major concern. A recent study inferred that pollinator species richnesses are decreasing more slowly in recent decades in several taxa and European countries. A more careful interpretation of these results reveals that this conclusion cannot be drawn and that we can only infer that declines decelerate for bees (Anthophila in the Netherlands.

  17. 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...

  18. 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...

  19. 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

  20. 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

  1. Pollination and protection against herbivory of Nepalese Coelogyninae (Orchidaceae)

    NARCIS (Netherlands)

    Subedi, A.; Chaudhary, R.P.; Achterberg, van C.; Heijerman, T.; 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 fi eld in Nepal. This information is urgently needed because many orchid species in Nepal are

  2. Insect assemblage and the pollination system in cocoa ecosystems

    African Journals Online (AJOL)

    SARAH

    2013-02-27

    Feb 27, 2013 ... Key words: Cocoa, pollinators, insect assemblage, Forcipomyia spp, pollination system. INTRODUCTION ... that the ecological prediction of plant reproductive successes and ..... non-interaction between some resident insects and the cocoa plant might be as a result of evolution of floral structure of the ...

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

    African Journals Online (AJOL)

    Because of the low application of this technology in Africa, research must be conducted in order to access the need of pollination service and then the profitability of this technology in the current African entomological fauna context. Despite its benefits, the use of managed Western honey bees can affect native pollinators ...

  4. 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.

  5. A fifth major genetic group among honeybees revealed in Syria.

    Science.gov (United States)

    Alburaki, Mohamed; Bertrand, Bénédicte; Legout, Hélène; Moulin, Sibyle; Alburaki, Ali; Sheppard, Walter Steven; Garnery, Lionel

    2013-12-06

    Apiculture has been practiced in North Africa and the Middle-East from antiquity. Several thousand years of selective breeding have left a mosaic of Apis mellifera subspecies in the Middle-East, many uniquely adapted and survived to local environmental conditions. In this study we explore the genetic diversity of A. mellifera from Syria (n = 1258), Lebanon (n = 169) and Iraq (n = 35) based on 14 short tandem repeat (STR) loci in the context of reference populations from throughout the Old World (n = 732). Our data suggest that the Syrian honeybee Apis mellifera syriaca occurs in both Syrian and Lebanese territories, with no significant genetic variability between respective populations from Syria and Lebanon. All studied populations clustered within a new fifth independent nuclear cluster, congruent with an mtDNA Z haplotype identified in a previous study. Syrian honeybee populations are not associated with Oriental lineage O, except for sporadic introgression into some populations close to the Turkish and Iraqi borders. Southern Syrian and Lebanese populations demonstrated high levels of genetic diversity compared to the northern populations. This study revealed the effects of foreign queen importations on Syrian bee populations, especially for the region of Tartus, where extensive introgression of A. m. anatolica and/or A. m. caucasica alleles were identified. The policy of creating genetic conservation centers for the Syrian subspecies should take into consideration the influence of the oriental lineage O from the northern Syrian border and the large population of genetically divergent indigenous honeybees located in southern Syria.

  6. Asynchronous diversification in a specialized plant-pollinator mutualism.

    Science.gov (United States)

    Ramírez, Santiago R; Eltz, Thomas; Fujiwara, Mikiko K; Gerlach, Günter; Goldman-Huertas, Benjamin; Tsutsui, Neil D; Pierce, Naomi E

    2011-09-23

    Most flowering plants establish mutualistic associations with insect pollinators to facilitate sexual reproduction. However, the evolutionary processes that gave rise to these associations remain poorly understood. We reconstructed the times of divergence, diversification patterns, and interaction networks of a diverse group of specialized orchids and their bee pollinators. In contrast to a scenario of coevolution by race formation, we show that fragrance-producing orchids originated at least three times independently after their fragrance-collecting bee mutualists. Whereas orchid diversification has apparently tracked the diversification of orchids' bee pollinators, bees appear to have depended on the diverse chemical environment of neotropical forests. We corroborated this apparent asymmetrical dependency by simulating co-extinction cascades in real interaction networks that lacked reciprocal specialization. These results suggest that the diversification of insect-pollinated angiosperms may have been facilitated by the exploitation of preexisting sensory biases of insect pollinators.

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

    DEFF Research Database (Denmark)

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

    2012-01-01

    . 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.......We studied the pollination biology of nine island Campanulaceae species: Azorina vidalii, Musschia aurea, M. wollastonii, Canarina canariensis, Campanula jacobaea, Nesocodon mauritianus, and three species of Heterochaenia. In addition, we compared C. canariensis to its two African mainland...... 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...

  8. Vibration transmission characteristics of the legs of freely standing honeybees

    DEFF Research Database (Denmark)

    Rohrseitz, Kristin; Kilpinen, Ole

    1997-01-01

    as the stimulator. This was also the case in freely standing honeybees, except around 400 Hz, where an average attenuation of approximately 6 dB was observed. In the fixed bee preparation, the vertical movements of the legs were also measured during horizontal stimulation. The vertical vibration amplitude...... of the legs was 15-20 dB lower than the horizontal stimulation amplitude. The electrophysiologically and behaviourally determined thresholds for vibration stimulation increased by approximately 10 dB, when the stimulus direction was changed from vertical to horizontal. These observations support the notion...

  9. Effect of Temperature on the Biotic Potential of Honeybee Microsporidia▿

    Science.gov (United States)

    Martín-Hernández, Raquel; Meana, Aránzazu; García-Palencia, Pilar; Marín, Pilar; Botías, Cristina; Garrido-Bailón, Encarna; Barrios, Laura; Higes, Mariano

    2009-01-01

    The biological cycle of Nosema spp. in honeybees depends on temperature. When expressed as total spore counts per day after infection, the biotic potentials of Nosema apis and N. ceranae at 33°C were similar, but a higher proportion of immature stages of N. ceranae than of N. apis were seen. At 25 and 37°C, the biotic potential of N. ceranae was higher than that of N. apis. The better adaptation of N. ceranae to complete its endogenous cycle at different temperatures clearly supports the observation of the different epidemiological patterns. PMID:19233948

  10. A primary report on honeybee space-flight breeding

    International Nuclear Information System (INIS)

    Guo Jun; Shi Wei; Ding Guiling; Lv Liping; Liu Zhiguang

    2009-01-01

    The semen of honeybees (Apis mellifera ligustica and Apis mellifera carnica) was carried by the recoverable satellite for a spaceflight and was inseminated instrumentally to the virgin queens after returning to the earth. The preliminary results showed that both the vitality of the sperm and the survival rate of SP 1 queen were lower than those of the control. Obvious variations in morphology appeared on the progeny workers of queens in SP 2 and in SP 3 generations, but most of variation were unfavorable. Mutants with desirable characters were not found after the space fight. (authors)

  11. Neonicotinoid-Coated Zea mays Seeds Indirectly Affect Honeybee Performance and Pathogen Susceptibility in Field Trials.

    Directory of Open Access Journals (Sweden)

    Mohamed Alburaki

    Full Text Available Thirty-two honeybee (Apis mellifera colonies were studied in order to detect and measure potential in vivo effects of neonicotinoid pesticides used in cornfields (Zea mays spp on honeybee health. Honeybee colonies were randomly split on four different agricultural cornfield areas located near Quebec City, Canada. Two locations contained cornfields treated with a seed-coated systemic neonicotinoid insecticide while the two others were organic cornfields used as control treatments. Hives were extensively monitored for their performance and health traits over a period of two years. Honeybee viruses (brood queen cell virus BQCV, deformed wing virus DWV, and Israeli acute paralysis virus IAPV and the brain specific expression of a biomarker of host physiological stress, the Acetylcholinesterase gene AChE, were investigated using RT-qPCR. Liquid chromatography-mass spectrometry (LC-MS was performed to detect pesticide residues in adult bees, honey, pollen, and corn flowers collected from the studied hives in each location. In addition, general hive conditions were assessed by monitoring colony weight and brood development. Neonicotinoids were only identified in corn flowers at low concentrations. However, honeybee colonies located in neonicotinoid treated cornfields expressed significantly higher pathogen infection than those located in untreated cornfields. AChE levels showed elevated levels among honeybees that collected corn pollen from treated fields. Positive correlations were recorded between pathogens and the treated locations. Our data suggests that neonicotinoids indirectly weaken honeybee health by inducing physiological stress and increasing pathogen loads.

  12. Altitude control in honeybees: joint vision-based learning and guidance.

    Science.gov (United States)

    Portelli, Geoffrey; Serres, Julien R; Ruffier, Franck

    2017-08-23

    Studies on insects' visual guidance systems have shed little light on how learning contributes to insects' altitude control system. In this study, honeybees were trained to fly along a double-roofed tunnel after entering it near either the ceiling or the floor of the tunnel. The honeybees trained to hug the ceiling therefore encountered a sudden change in the tunnel configuration midways: i.e. a "dorsal ditch". Thus, the trained honeybees met a sudden increase in the distance to the ceiling, corresponding to a sudden strong change in the visual cues available in their dorsal field of view. Honeybees reacted by rising quickly and hugging the new, higher ceiling, keeping a similar forward speed, distance to the ceiling and dorsal optic flow to those observed during the training step; whereas bees trained to follow the floor kept on following the floor regardless of the change in the ceiling height. When trained honeybees entered the tunnel via the other entry (the lower or upper entry) to that used during the training step, they quickly changed their altitude and hugged the surface they had previously learned to follow. These findings clearly show that trained honeybees control their altitude based on visual cues memorized during training. The memorized visual cues generated by the surfaces followed form a complex optic flow pattern: trained honeybees may attempt to match the visual cues they perceive with this memorized optic flow pattern by controlling their altitude.

  13. 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

  14. Pollinator adaptation and the evolution of floral nectar sugar composition.

    Science.gov (United States)

    Abrahamczyk, S; Kessler, M; Hanley, D; Karger, D N; Müller, M P J; Knauer, A C; Keller, F; Schwerdtfeger, M; Humphreys, A M

    2017-01-01

    A long-standing debate concerns whether nectar sugar composition evolves as an adaptation to pollinator dietary requirements or whether it is 'phylogenetically constrained'. Here, we use a modelling approach to evaluate the hypothesis that nectar sucrose proportion (NSP) is an adaptation to pollinators. We analyse ~ 2100 species of asterids, spanning several plant families and pollinator groups (PGs), and show that the hypothesis of adaptation cannot be rejected: NSP evolves towards two optimal values, high NSP for specialist-pollinated and low NSP for generalist-pollinated plants. However, the inferred adaptive process is weak, suggesting that adaptation to PG only provides a partial explanation for how nectar evolves. Additional factors are therefore needed to fully explain nectar evolution, and we suggest that future studies might incorporate floral shape and size and the abiotic environment into the analytical framework. Further, we show that NSP and PG evolution are correlated - in a manner dictated by pollinator behaviour. This contrasts with the view that a plant necessarily has to adapt its nectar composition to ensure pollination but rather suggests that pollinators adapt their foraging behaviour or dietary requirements to the nectar sugar composition presented by the plants. Finally, we document unexpectedly sucrose-poor nectar in some specialized nectarivorous bird-pollinated plants from the Old World, which might represent an overlooked form of pollinator deception. Thus, our broad study provides several new insights into how nectar evolves and we conclude by discussing why maintaining the conceptual dichotomy between adaptation and constraint might be unhelpful for advancing this field. © 2016 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2016 European Society For Evolutionary Biology.

  15. 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

  16. 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

  17. Hygienic and grooming behaviors in African and European honeybees-New damage categories in Varroa destructor.

    Science.gov (United States)

    Nganso, Beatrice T; Fombong, Ayuka T; Yusuf, Abdullahi A; Pirk, Christian W W; Stuhl, Charles; Torto, Baldwyn

    2017-01-01

    Varroa destructor is an ectoparasitic pest of honeybees, and a threat to the survival of the apiculture industry. Several studies have shown that unlike European honeybees, African honeybee populations appear to be minimally affected when attacked by this mite. However, little is known about the underlying drivers contributing to survival of African honeybee populations against the mite. We hypothesized that resistant behavioral defenses are responsible for the survival of African honeybees against the ectoparasite. We tested this hypothesis by comparing grooming and hygienic behaviors in the African savannah honeybee Apis mellifera scutellata in Kenya and A. mellifera hybrids of European origin in Florida, USA against the mite. Grooming behavior was assessed by determining adult mite infestation levels, daily mite fall per colony and percentage mite damage (as an indicator of adult grooming rate), while hygienic behavior was assessed by determining the brood removal rate after freeze killing a section of the brood. Our results identified two additional undescribed damaged mite categories along with the six previously known damage categories associated with the grooming behavior of both honeybee subspecies. Adult mite infestation level was approximately three-fold higher in A. mellifera hybrids of European origin than in A. m. scutellata, however, brood removal rate, adult grooming rate and daily natural mite fall were similar in both honeybee subspecies. Unlike A. mellifera hybrids of European origin, adult grooming rate and brood removal rate did not correlate with mite infestation levels on adult worker honeybee of A. m. scutellata though they were more aggressive towards the mites than their European counterparts. Our results provide valuable insights into the tolerance mechanisms that contribute to the survival of A. m. scutellata against the mite.

  18. Flowering mechanisms, pollination strategies and floral scent analyses of syntopically co-flowering Homalomena spp. (Araceae) on Borneo.

    Science.gov (United States)

    Hoe, Y C; Gibernau, M; Maia, A C D; Wong, S Y

    2016-07-01

    In this study, the flowering mechanisms and pollination strategies of seven species of the highly diverse genus Homalomena (Araceae) were investigated in native populations of West Sarawak, Borneo. The floral scent compositions were also recorded for six of these species. The selected taxa belong to three out of four complexes of the section Cyrtocladon (Hanneae, Giamensis and Borneensis). The species belonging to the Hanneae complex exhibited longer anthesis (53-62 h) than those of the Giamensis and Borneensis complexes (ca. 30 h). Species belonging to the Hanneae complex underwent two floral scent emission events in consecutive days, during the pistillate and staminate phases of anthesis. In species belonging to the Giamensis and Borneensis complexes, floral scent emission was only evident to the human nose during the pistillate phase. A total of 33 volatile organic compounds (VOCs) were detected in floral scent analyses of species belonging to the Hanneae complex, whereas 26 VOCs were found in samples of those belonging to the Giamensis complex. The floral scent blends contained uncommon compounds in high concentration, which could ensure pollinator discrimination. Our observations indicate that scarab beetles (Parastasia gestroi and P. nigripennis; Scarabaeidae, Rutelinae) are the pollinators of the investigated species of Homalomena, with Chaloenus schawalleri (Chrysomelidae, Galeuricinae) acting as a secondary pollinator. The pollinators utilise the inflorescence for food, mating opportunities and safe mating arena as rewards. Flower-breeding flies (Colocasiomyia nigricauda and C. aff. heterodonta; Diptera, Drosophilidae) and terrestrial hydrophilid beetles (Cycreon sp.; Coleoptera, Hydrophilidae) were also frequently recovered from inflorescences belonging to all studied species (except H. velutipedunculata), but they probably do not act as efficient pollinators. Future studies should investigate the post-mating isolating barriers among syntopically co

  19. 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

  20. 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.

  1. Cognitive Aspects of Comb-Building in the Honeybee?

    Directory of Open Access Journals (Sweden)

    Vincent Gallo

    2018-06-01

    Full Text Available The wax-made comb of the honeybee is a masterpiece of animal architecture. The highly regular, double-sided hexagonal structure is a near-optimal solution to storing food and housing larvae, economizing on building materials and space. Elaborate though they may seem, such animal constructions are often viewed as the result of ‘just instinct,’ governed by inflexible, pre-programmed, innate behavior routines. An inspection of the literature on honeybee comb construction, however, reveals a different picture. Workers have to learn, at least in part, certain elements of the technique, and there is considerable flexibility in terms of how the shape of the comb and its gradual manufacture is tailored to the circumstances, especially the available space. Moreover, we explore the 2-century old and now largely forgotten work by François Huber, where glass screens were placed between an expanding comb construction and the intended target wall. Bees took corrective action before reaching the glass obstacle, and altered the ongoing construction so as to reach the nearest wooden wall. Though further experiments will be necessary, these results suggest a form of spatial planning skills. We discuss these findings in the context of what is now known about insect cognition, and ask if it is possible that the production of hexagonal wax combs is the result of behavioral heuristics where a complex structure emerges as the result of simple behavioral rules applied by each individual, or whether prospective cognition might be involved.

  2. Context odor presentation during sleep enhances memory in honeybees.

    Science.gov (United States)

    Zwaka, Hanna; Bartels, Ruth; Gora, Jacob; Franck, Vivien; Culo, Ana; Götsch, Moritz; Menzel, Randolf

    2015-11-02

    Sleep plays an important role in stabilizing new memory traces after learning [1-3]. Here we investigate whether sleep's role in memory processing is similar in evolutionarily distant species and demonstrate that a context trigger during deep-sleep phases improves memory in invertebrates, as it does in humans. We show that in honeybees (Apis mellifera), exposure to an odor during deep sleep that has been present during learning improves memory performance the following day. Presentation of the context odor during wake phases or novel odors during sleep does not enhance memory. In humans, memory consolidation can be triggered by presentation of a context odor during slow-wave sleep that had been present during learning [3-5]. Our results reveal that deep-sleep phases in honeybees have the potential to prompt memory consolidation, just as they do in humans. This study provides strong evidence for a conserved role of sleep-and how it affects memory processes-from insects to mammals. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Neonicotinoids interfere with specific components of navigation in honeybees.

    Directory of Open Access Journals (Sweden)

    Johannes Fischer

    Full Text Available Three neonicotinoids, imidacloprid, clothianidin and thiacloprid, agonists of the nicotinic acetylcholine receptor in the central brain of insects, were applied at non-lethal doses in order to test their effects on honeybee navigation. A catch-and-release experimental design was applied in which feeder trained bees were caught when arriving at the feeder, treated with one of the neonicotinoids, and released 1.5 hours later at a remote site. The flight paths of individual bees were tracked with harmonic radar. The initial flight phase controlled by the recently acquired navigation memory (vector memory was less compromised than the second phase that leads the animal back to the hive (homing flight. The rate of successful return was significantly lower in treated bees, the probability of a correct turn at a salient landscape structure was reduced, and less directed flights during homing flights were performed. Since the homing phase in catch-and-release experiments documents the ability of a foraging honeybee to activate a remote memory acquired during its exploratory orientation flights, we conclude that non-lethal doses of the three neonicotinoids tested either block the retrieval of exploratory navigation memory or alter this form of navigation memory. These findings are discussed in the context of the application of neonicotinoids in plant protection.

  4. Neonicotinoids Interfere with Specific Components of Navigation in Honeybees

    Science.gov (United States)

    Fischer, Johannes; Müller, Teresa; Spatz, Anne-Kathrin; Greggers, Uwe; Grünewald, Bernd; Menzel, Randolf

    2014-01-01

    Three neonicotinoids, imidacloprid, clothianidin and thiacloprid, agonists of the nicotinic acetylcholine receptor in the central brain of insects, were applied at non-lethal doses in order to test their effects on honeybee navigation. A catch-and-release experimental design was applied in which feeder trained bees were caught when arriving at the feeder, treated with one of the neonicotinoids, and released 1.5 hours later at a remote site. The flight paths of individual bees were tracked with harmonic radar. The initial flight phase controlled by the recently acquired navigation memory (vector memory) was less compromised than the second phase that leads the animal back to the hive (homing flight). The rate of successful return was significantly lower in treated bees, the probability of a correct turn at a salient landscape structure was reduced, and less directed flights during homing flights were performed. Since the homing phase in catch-and-release experiments documents the ability of a foraging honeybee to activate a remote memory acquired during its exploratory orientation flights, we conclude that non-lethal doses of the three neonicotinoids tested either block the retrieval of exploratory navigation memory or alter this form of navigation memory. These findings are discussed in the context of the application of neonicotinoids in plant protection. PMID:24646521

  5. Combating Varroa destructor in Honeybee Colonies Using Flumethrin or Fluvalinate

    Directory of Open Access Journals (Sweden)

    A. Gregorc

    2007-01-01

    Full Text Available Mite mortality in two apiaries, one with 32 and the other with 15 honeybee (Apis mellifera carnica colonies, was recorded prior to and after flumethrin or fluvalinate treatments and after a control, oxalic-acid application. During the 42- and 51-day pre-treatment periods, the average daily natural mite drop was 0.04 (± 0.04 and 2.82 (± 2.19, respectively, which represents 1.09% (± 1.06 and 3.84% (± 3.04 of the total number of mites found during the experiment. The flumethrin or fluvalinate applications resulted in an average mite mortality at the two apiaries of 214.46 (± 260.02 and 4,098.64 (± 2,508.31. The treatments resulted in a 19.11% (± 14.62 and a 39.28% (± 10.47 reduction in the number of mites in slightly infested colonies and 94.30% (± 4.26 and 96.24% (± 3.14 in highly infested colonies. The difference in treatment efficacy between both apiaries was significant (P < 0.001 and indicates that fluvalinate and flumethrin are highly efficacious in dealing with highly infested honeybee colonies with sealed brood. The importance of effective mite control in colonies with a high level of natural mite mortality is discussed in this study.

  6. A DNA barcoding approach to characterize pollen collected by honeybees.

    Directory of Open Access Journals (Sweden)

    Andrea Galimberti

    Full Text Available In the present study, we investigated DNA barcoding effectiveness to characterize honeybee pollen pellets, a food supplement largely used for human nutrition due to its therapeutic properties. We collected pollen pellets using modified beehives placed in three zones within an alpine protected area (Grigna Settentrionale Regional Park, Italy. A DNA barcoding reference database, including rbcL and trnH-psbA sequences from 693 plant species (104 sequenced in this study was assembled. The database was used to identify pollen collected from the hives. Fifty-two plant species were identified at the molecular level. Results suggested rbcL alone could not distinguish among congeneric plants; however, psbA-trnH identified most of the pollen samples at the species level. Substantial variability in pollen composition was observed between the highest elevation locality (Alpe Moconodeno, characterized by arid grasslands and a rocky substrate, and the other two sites (Cornisella and Ortanella at lower altitudes. Pollen from Ortanella and Cornisella showed the presence of typical deciduous forest species; however in samples collected at Ortanella, pollen of the invasive Lonicera japonica, and the ornamental Pelargonium x hortorum were observed. Our results indicated pollen composition was largely influenced by floristic local biodiversity, plant phenology, and the presence of alien flowering species. Therefore, pollen molecular characterization based on DNA barcoding might serve useful to beekeepers in obtaining honeybee products with specific nutritional or therapeutic characteristics desired by food market demands.

  7. The organization of honeybee ocelli: Regional specializations and rhabdom arrangements.

    Science.gov (United States)

    Ribi, Willi; Warrant, Eric; Zeil, Jochen

    2011-11-01

    We have re-investigated the organization of ocelli in honeybee workers and drones. Ocellar lenses are divided into a dorsal and a ventral part by a cusp-shaped indentation. The retina is also divided, with a ventral retina looking skywards and a dorsal retina looking at the horizon. The focal plane of lenses lies behind the retina in lateral ocelli, but within the dorsal retina in the median ocellus of both workers and drones. Ventral retinula cells are ca. 25μm long with dense screening pigments. Dorsal retinula cells are ca. 60μm long with sparse pigmentation mainly restricted to their proximal parts. Pairs of retinula cells form flat, non-twisting rhabdom sheets with elongated, straight, rectangular cross-sections, on average 8.7μm long and 1μm wide. Honeybee ocellar rhabdoms have shorter and straighter cross-sections than those recently described in the night-active bee Megalopta genalis. Across the retina, rhabdoms form a fan-shaped pattern of orientations. In each ocellus, ventral and dorsal retinula cell axons project into two separate neuropils, converging on few large neurons in the dorsal, and on many small neurons in the ventral neuropil. The divided nature of the ocelli, together with the particular construction and arrangement of rhabdoms, suggest that ocelli are not only involved in attitude control, but might also provide skylight polarization compass information. Copyright © 2011 Elsevier Ltd. All rights reserved.

  8. Sensory coding of nest-site value in honeybee swarms.

    Science.gov (United States)

    Seeley, Thomas D; Visscher, P Kirk

    2008-12-01

    This study investigates the first stage of the decision-making process of a honeybee swarm as it chooses a nest site: how a scout bee codes the value of a potential nest site in the waggle dances she produces to represent this site. We presented honeybee swarms with a two-alternative choice between a high-value site and a medium-value site and recorded the behavior of individually identifiable scout bees as they reported on these two alternatives. We found that bees performed equally lengthy inspections at the two sites, but that, on the swarm cluster, they performed more dance circuits per bee for the high-value site. We also found that there was much individual-level noise in the coding of site value, but that there were clear population-level differences in total dance circuits produced for the two sites. The first bee to find a site had a high probability of reporting the site with a waggle dance, regardless of its value. This discoverer-should-dance phenomenon may help ensure that a swarm gives attention to all discovered sites. There was rapid decay in the dance response; the number of dance circuits produced by a bee after visiting a site decreased linearly over sequential visits, and eventually each bee ceased visiting her site. This decay, or ;leakage', in the accumulation of bees at a site improves a swarm's decision-making ability by helping a swarm avoid making fast-decision errors.

  9. Linking Land Cover Data and Crop Yields for Mapping and Assessment of Pollination Services in Europe

    Directory of Open Access Journals (Sweden)

    Maria Luisa Paracchini

    2013-09-01

    Full Text Available Pollination is a key ecosystem service as many crops but in particular, fruits and vegetables are partially dependent on pollinating insects to produce food for human consumption. Here we assessed how pollination services are delivered at the European scale. We used this assessment to estimate the relative contribution of wild pollinators to crop production. We developed an index of relative pollination potential, which is defined as the relative potential or relative capacity of ecosystems to support crop pollination. The model for relative pollination potential is based on the assumption that different habitats, but in particular forest edges, grasslands rich in flowers and riparian areas, offer suitable sites for wild pollinator insects. Using data of the foraging range of wild bees with short flight distances, we linked relative pollination potential to regional statistics of crop production. At aggregated EU level, the absence of insect pollination would result in a reduction of between 25% and 32% of the total production of crops which are partially dependent on insect pollination, depending on the data source used for the assessment. This production deficit decreases to 2.5% if only the relative pollination potential of a single guild of pollinators is considered. A strength of our approach is the spatially-explicit link between land cover based relative pollination potential and crop yield which enables a general assessment of the benefits that are derived from pollination services in Europe while providing insight where pollination gaps in the landscape occur.

  10. Species Distribution Models for Crop Pollination: A Modelling Framework Applied to Great Britain

    NARCIS (Netherlands)

    Polce, C.; Termansen, M.; Aguirre-Gutiérrez, J.; Boatman, N.D.; Budge, G.E.; Crowe, A.; Garratt, M.P.; Pietravalle, S.; Potts, S.G.; Ramirez, J. A.; Somerwill, K.E.; Biesmeijer, J.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

  11. Floral advertisement scent in a changing plant-pollinators market.

    Science.gov (United States)

    Filella, Iolanda; Primante, Clara; Llusià, Joan; Martín González, Ana M; Seco, Roger; Farré-Armengol, Gerard; Rodrigo, Anselm; Bosch, Jordi; Peñuelas, Josep

    2013-12-05

    Plant-pollinator systems may be considered as biological markets in which pollinators choose between different flowers that advertise their nectar/pollen rewards. Although expected to play a major role in structuring plant-pollinator interactions, community-wide patterns of flower scent signals remain largely unexplored. Here we show for the first time that scent advertisement is higher in plant species that bloom early in the flowering period when pollinators are scarce relative to flowers than in species blooming later in the season when there is a surplus of pollinators relative to flowers. We also show that less abundant flowering species that may compete with dominant species for pollinator visitation early in the flowering period emit much higher proportions of the generalist attractant β-ocimene. Overall, we provide a first community-wide description of the key role of seasonal dynamics of plant-specific flower scent emissions, and reveal the coexistence of contrasting plant signaling strategies in a plant-pollinator market.

  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. 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.

  14. 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.

  15. 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.

  16. 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

  17. Pollination success of Lotus corniculatus (L.) in an urban context

    Science.gov (United States)

    Pellissier, Vincent; Muratet, Audrey; Verfaillie, Fabien; Machon, Nathalie

    2012-02-01

    Most anthropogenic activities are known to have deleterious effects on pollinator communities. However, little is known about the influence of urbanization on pollination ecosystem services. Here, we assessed the pollination service on Lotus corniculatus (L.), a self-sterile, strictly entogamous Fabaceae commonly observed in urban and suburban areas. We assessed the pollination success of artificial Lotus corniculatus populations at three levels: at large scale, along an urbanization gradient; at intermediate scale, based on landscape fragmentation within a 250 m radius and at local scale based on floral resource abundance and local habitat type. The main findings were that the pollination success, when assessed with the number of fruit produced per inflorescence, was lower in urban areas than in suburban ones, and was negatively affected by the number of impervious spaces in the neighborhood. The relationship between the number of fruits and the distance to the nearest impervious space was either positive or negative, depending on the gray/green ratio (low vs. high). Finally, on a local scale, floral resource abundance had a negative effect on pollination success when L. corniculatus populations were located in paved courtyards, and a positive one when they were located in parks. Pollination success seems to be explained by two intertwined gradients: landscape fragmentation estimated by the number of impervious spaces in a 250 m radius around L. corniculatus populations, and the behavior of bumblebees toward birdsfoot trefoil and floral displays, which appears to differ depending on whether a neighborhood is densely or sparsely urbanized. An abundance of attracting floral resources seems to enhance pollination success for L. corniculatus if it is not too isolated from other green spaces. These results have important implications for the sustainability of pollination success in towns by identifying local and landscape factors that influence reproductive success of

  18. Pterandra pyroidea: a case of pollination shift within Neotropical Malpighiaceae

    Science.gov (United States)

    Cappellari, Simone C.; Haleem, Muhammad A.; Marsaioli, Anita J.; Tidon, Rosana; Simpson, Beryl B.

    2011-01-01

    Background and Aims Most Neotropical species of Malpighiaceae produce floral fatty oils in calyx glands to attract pollinating oil-collecting bees, which depend on this resource for reproduction. This specialized type of pollination system tends to be lost in members of the family that occur outside the geographic distribution (e.g. Africa) of Neotropical oil-collecting bees. This study focused on the pollination ecology, chemical ecology and reproductive biology of an oil flower species, Pterandra pyroidea (Malpighiaceae) from the Brazilian Cerrado. Populations of this species consist of plants with oil-secreting (glandular) flowers, plants with non-oil-secreting flowers (eglandular) or a mix of both plant types. This study specifically aims to clarify the role of eglandular morphs in this species. Methods Data on pollinators were recorded by in situ observations. Breeding system experiments were conducted by isolating inflorescences and by enzymatic reactions. Floral resources, pollen and floral oils offered by this species were analysed by staining and a combination of various spectroscopic methods. Key Results Eglandular flowers of P. pyroidea do not act as mimics of their oil-producing conspecifics to attract pollinators. Instead, both oil-producing and oil-free flowers depend on pollen-collecting bees for reproduction, and their main pollinators are bumble-bees. Floral oils produced by glandular flowers are less complex than those described in closely related genera. Conclusions Eglandular flowers represent a shift in the pollination system in which oil is being lost and pollen is becoming the main reward of P. pyroidea flowers. Pollination shifts of this kind have hitherto not been demonstrated empirically within Neotropical Malpighiaceae and this species exhibits an unusual transition from a specialized towards a generalized pollination system in an area considered the hotspot of oil-collecting bee diversity in the Neotropics. Transitions of this type

  19. 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.

  20. Minute pollinators: The role of thrips (Thysanoptera) as pollinators of pointleaf manzanita, Arctostaphylos pungens (Ericaceae)

    OpenAIRE

    Eliyahu, Dorit; McCall, Andrew C.; Lauck, Marina; Trakhtenbrot, Ana; Bronstein, Judith L.

    2015-01-01

    The feeding habits of thrips on plant tissue, and their ability to transmit viral diseases to their host plants, have usually placed these insects in the general category of pests. However, the characteristics that make them economically important, their high abundance and short- and long-distance movement capability, may also make them effective pollinators. We investigated this lesser-known role of thrips in pointleaf manzanita (Arctostaphylos pungens), a Southwestern US shrub. We measured ...

  1. Minute pollinators: The role of thrips (Thysanoptera) as pollinators of pointleaf manzanita, Arctostaphylos pungens (Ericaceae).

    Science.gov (United States)

    Eliyahu, Dorit; McCall, Andrew C; Lauck, Marina; Trakhtenbrot, Ana; Bronstein, Judith L

    The feeding habits of thrips on plant tissue, and their ability to transmit viral diseases to their host plants, have usually placed these insects in the general category of pests. However, the characteristics that make them economically important, their high abundance and short- and long-distance movement capability, may also make them effective pollinators. We investigated this lesser-known role of thrips in pointleaf manzanita ( Arctostaphylos pungens ), a Southwestern US shrub. We measured the abundance of three species of thrips ( Orothrips kelloggii, Oligothrips oreios , and Frankliniella occidentalis ), examined their pollen-carrying capability, and conducted an exclusion experiment in order to determine whether thrips are able to pollinate this species, and if they do, whether they actually contribute to the reproductive success of the plant. Our data suggest that indeed thrips pollinate and do contribute significantly to reproductive success. Flowers exposed to thrips only produced significantly more fruit than did flowers from which all visitors were excluded. The roles of thrips as antagonists/mutualists are examined in the context of the numerous other floral visitors to the plant.

  2. Genotypic Influence on Aversive Conditioning in Honeybees, Using a Novel Thermal Reinforcement Procedure

    Science.gov (United States)

    Junca, Pierre; Carcaud, Julie; Moulin, Sibyle; Garnery, Lionel; Sandoz, Jean-Christophe

    2014-01-01

    In Pavlovian conditioning, animals learn to associate initially neutral stimuli with positive or negative outcomes, leading to appetitive and aversive learning respectively. The honeybee (Apis mellifera) is a prominent invertebrate model for studying both versions of olfactory learning and for unraveling the influence of genotype. As a queen bee mates with about 15 males, her worker offspring belong to as many, genetically-different patrilines. While the genetic dependency of appetitive learning is well established in bees, it is not the case for aversive learning, as a robust protocol was only developed recently. In the original conditioning of the sting extension response (SER), bees learn to associate an odor (conditioned stimulus - CS) with an electric shock (unconditioned stimulus - US). This US is however not a natural stimulus for bees, which may represent a potential caveat for dissecting the genetics underlying aversive learning. We thus first tested heat as a potential new US for SER conditioning. We show that thermal stimulation of several sensory structures on the bee’s body triggers the SER, in a temperature-dependent manner. Moreover, heat applied to the antennae, mouthparts or legs is an efficient US for SER conditioning. Then, using microsatellite analysis, we analyzed heat sensitivity and aversive learning performances in ten worker patrilines issued from a naturally inseminated queen. We demonstrate a strong influence of genotype on aversive learning, possibly indicating the existence of a genetic determinism of this capacity. Such determinism could be instrumental for efficient task partitioning within the hive. PMID:24828422

  3. 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.

  4. Estratégias fenológicas de Senna cana (Nees & Mart. H.S. Irwin & Barneby (Fabaceae: Caesalpinioideae como mecanismo eficiente para atração de polinizadores Phenological strategies of Senna cana (Nees & Mart. H.S. Irwin & Barneby (Fabaceae: Caesalpinioideae as efficient mechanisms for attracting pollinators

    Directory of Open Access Journals (Sweden)

    Isys Mascarenhas Souza

    2012-06-01

    Full Text Available Este trabalho verificou a importância das estratégias fenológicas de Senna cana na atração de visitantes e polinizadores na mata ciliar do rio Lençóis, Chapada Diamantina, Bahia. As observações fenológicas foliares (queda foliar e brotamento e reprodutivas (botão, flor, fruto imaturo e fruto maduro foram mensais (18 meses em 10 indivíduos marcados. Para a biologia floral observou-se: antese, duração das flores, receptividade estigmática, viabilidade polínica, presença de osmóforos e pigmentos que refletem raios ultravioleta. Foram realizados testes de autopolinização manual, espontânea e polinização cruzada. Os visitantes e polinizadores foram determinados observando-se: horário, duração, freqüência das visitas e comportamento de forrageio. Senna cana é uma espécie perenifólia episódica, com eventos reprodutivos sazonais e altamente sincrônicos (floração intermediária no período chuvoso e frutificação longa no período seco. Tais características na floração, somadas à síndrome de melitofilia, configuram importantes estratégias para atração de visitantes florais, dentre os quais Xylocopa frontalis e X. grisescens foram classificadas enquanto potenciais polinizadores. A autoincompatibilidade e o máximo de frutos produzidos após polinização cruzada são mecanismos reprodutivos favorecidos pelas estratégias fenológicas e síndrome de polinização apresentadas pela espécie.The present work evaluated the importance of the phenological strategies of Senna cana in attracting floral visitors and pollinators in an riparian forest along the Lençóis River, in Chapada Diamantina, Bahia, Brazil. Vegetative and reproductive phenological observations (leaf fall, leaf flushing, flowering, and fruiting were made on a monthly basis among a group of 10 individuals. The floral biology patterns observed included: anthesis, duration of the flowers, stigma receptivity, pollen viability, and the presence of

  5. Bay laurel (Laurus nobilis) as potential antiviral treatment in naturally BQCV infected honeybees.

    Science.gov (United States)

    Aurori, Adriana C; Bobiş, Otilia; Dezmirean, Daniel S; Mărghitaş, Liviu A; Erler, Silvio

    2016-08-15

    Viral diseases are one of the multiple factors associated with honeybee colony losses. Apart from their innate immune system, including the RNAi machinery, honeybees can use secondary plant metabolites to reduce or fully cure pathogen infections. Here, we tested the antiviral potential of Laurus nobilis leaf ethanolic extracts on forager honeybees naturally infected with BQCV (Black queen cell virus). Total viral loads were reduced even at the lowest concentration tested (1mg/ml). Higher extract concentrations (≥5mg/ml) significantly reduced virus replication. Measuring vitellogenin gene expression as an indicator for transcript homeostasis revealed constant RNA levels before and after treatment, suggesting that its expression was not impacted by the L. nobilis treatment. In conclusion, plant secondary metabolites can reduce virus loads and virus replication in naturally infected honeybees. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Genetic reincarnation of workers as queens in the Eastern honeybee Apis cerana.

    Science.gov (United States)

    Holmes, M J; Tan, K; Wang, Z; Oldroyd, B P; Beekman, M

    2015-01-01

    Thelytokous parthenogenesis, or the asexual production of female offspring, is rare in the animal kingdom, but relatively common in social Hymenoptera. However, in honeybees, it is only known to be ubiquitous in one subspecies of Apis mellifera, the Cape honeybee, A. mellifera capensis. Here we report the appearance of queen cells in two colonies of the Eastern honeybee Apis cerana that no longer contained a queen or queen-produced brood to rear queens from. A combination of microsatellite genotyping and the timing of the appearance of these individuals excluded the possibility that they had been laid by the original queen. Based on the genotypes of these individuals, thelytokous production by natal workers is the most parsimonious explanation for their existence. Thus, we present the first example of thelytoky in a honeybee outside A. mellifera. We discuss the evolutionary and ecological consequences of thelytoky in A. cerana, in particular the role thelytoky may play in the recent invasions by populations of this species.

  7. Linking Land Cover Data and Crop Yields for Mapping and Assessment of Pollination Services in Europe

    OpenAIRE

    Grazia Zulian; Joachim Maes; Maria Luisa Paracchini

    2013-01-01

    Pollination is a key ecosystem service as many crops but in particular, fruits and vegetables are partially dependent on pollinating insects to produce food for human consumption. Here we assessed how pollination services are delivered at the European scale. We used this assessment to estimate the relative contribution of wild pollinators to crop production. We developed an index of relative pollination potential, which is defined as the relative potential or relative capacity of ecosystems t...

  8. Floral scent composition predicts bee pollination system in five butterfly bush (Buddleja, Scrophulariaceae) species.

    OpenAIRE

    Gong, W-C; Chen, G; Vereecken, Nicolas; Dunn, B L; Ma, Y-P; Sun, W-B

    2014-01-01

    Traditionally, plant-pollinator interactions have been interpreted as pollination syndrome. However, the validity of pollination syndrome has been widely doubted in modern studies of pollination ecology. The pollination ecology of five Asian Buddleja species, B. asiatica, B. crispa, B. forrestii, B. macrostachya and B. myriantha, in the Sino-Himalayan region in Asia, flowering in different local seasons, with scented inflorescences were investigated during 2011 and 2012. These five species ex...

  9. 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.

  10. Generalización en las interacciones entre plantas y polinizadores Generalizations in the interactions between plants and pollinators

    Directory of Open Access Journals (Sweden)

    JOSÉ M. GÓMEZ

    2002-03-01

    systems can arise by several non-exclusive factors. One kind of factors are related to the ability of pollinators of acting as true selective agents. Despite that many studies have shown that pollinators can provoke phenotypic selection on floral traits, only occasionally it has been shown that this selection actually produces any response to selection. Two main reasons can explain why pollinators cannot induce adaptations in many plants: (1a a significant spatial and temporal variability in pollinator abundance and identity highly reduces the possibilities of congruent selection on floral traits; (1b the occurrence of extrinsic factors acting during another stages of the plant reproductive and recruitment processes can also decrease the actual effect that pollinators has on fitness. A second group of factors are those related with the fact that, to specialization occurs, it is necessary that two different pollinators can constitute as completely separated selective agents, by differing in their per-visit efficiencies and/or floral trait preferences. By contrast, similarity in efficiency and preference will constrain specialization even although pollinators act as selective pressures, since plant will have not any criteria to benefit a given pollinator species with respect to the other

  11. Temporal pattern of africanization in a feral honeybee population from Texas inferred from mitochondrial DNA

    OpenAIRE

    Pinto, M. Alice; Rubink, William L.; Coulson, Robert N.; Patton, John C.; Johnston, J. Spencer

    2004-01-01

    The invasion of Africanized honeybees (Apis mellifera L.) in the Americas provides a window of opportunity to study the dynamics of secondary contact of subspecies of bees that evolved in allopatry in ecologically distinctive habitats of the Old World. We report here the results of an 11-year mitochondrial DNA survey of a feral honeybee population from southern United States (Texas). The mitochondrial haplotype (mitotype) frequencies changed radically during the 11-year study peri...

  12. Drag reduction effects facilitated by microridges inside the mouthparts of honeybee workers and drones.

    Science.gov (United States)

    Li, Chu-Chu; Wu, Jia-Ning; Yang, Yun-Qiang; Zhu, Ren-Gao; Yan, Shao-Ze

    2016-01-21

    The mouthpart of a honeybee is a natural well-designed micropump that uses a reciprocating glossa through a temporary tube comprising a pair of galeae and labial palpi for loading nectar. The shapes and sizes of mouthparts differ among castes of honeybees, but the diversities of the functional microstructures inside the mouthparts of honeybee workers and drones remain poorly understood. Through scanning electron microscopy, we found the dimensional difference of uniformly distributed microridges on the inner galeae walls of Apis mellifera ligustica workers and drones. Subsequently, we recorded the feeding process of live honeybees by using a specially designed high-speed camera system. Considering the microridges and kinematics of the glossa, we constructed a hydrodynamic model to calculate the friction coefficient of the mouthpart. In addition, we test the drag reduction through the dimensional variations of the microridges on the inner walls of mouthparts. Theoretical estimations of the friction coefficient with respect to dipping frequency show that inner microridges can reduce friction during the feeding process of honeybees. The effects of drag reduction regulated by specific microridges were then compared. The friction coefficients of the workers and drones were found to be 0.011±0.007 (mean±s.d.) and 0.045±0.010, respectively. These results indicate that the mouthparts of workers are more capable of drag reduction compared with those of drones. The difference was analyzed by comparing the foraging behavior of the workers and drones. Workers are equipped with well-developed hypopharyngeal, and their dipping frequency is higher than that of drones. Our research establishes a critical link between microridge dimensions and drag reduction capability during the nectar feeding of honeybees. Our results reveal that microridges inside the mouthparts of honeybee workers and drones reflect the caste-related life cycles of honeybees. Copyright © 2015 Elsevier Ltd

  13. Mouthpart grooming behavior in honeybees: Kinematics and sectionalized friction between foreleg tarsi and proboscises.

    Science.gov (United States)

    Linghu, Zelin; Wu, Jianing; Wang, Changlong; Yan, Shaoze

    2015-11-01

    The mouthpart of a honeybee is prone to contamination by granular particles such as pollen or dirt from the field. To clean the contaminated mouthparts, a honeybee swings its foreleg tarsi forward and backward to brush the proboscis continuously, sweeping the contaminant from the surfaces of the labial palpi, galeae, and bushy haired tongue (glossa). This grooming behavior has been documented but the dynamic characteristics therein have not been investigated yet. We quantified the grooming behavior of a honeybee from the perspective of kinematic and tribological properties. We captured high-speed videos that recorded the mouthpart grooming patterns of honeybees from the front and side views and measured the friction on the grooming surfaces using a precision dynamometer. During grooming, a honeybee first positions the mouthpart and then places a pair of foreleg tarsi to the tubular-folded galea. The tarsi press the galea and labial palpi and slide downward while keeping close contact with the galea. Then, the hairy glossa stretches out of the temporary tube with the glossa setae erected. The tarsi slowly slide down when grooming the glossa. In the return stroke of grooming, the foreleg tarsi detach from the mouthpart and retreat swiftly. Friction analysis shows that the honeybees can coordinate the velocity of the foreleg tarsi to the sectionalized tribological property of the tarsus-mouthpart interface. The specific grooming pattern enables honeybees to save energy and resist wear, resulting in a possible highly evolved grooming strategy. These findings lead to further understanding of the honeybee's grooming behavior facilitated by the special motion kinematics and friction characteristics. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Antennal proteome comparison of sexually mature drone and forager honeybees.

    Science.gov (United States)

    Feng, Mao; Song, Feifei; Aleku, Dereje Woltedji; Han, Bin; Fang, Yu; Li, Jianke

    2011-07-01

    Honeybees have evolved an intricate system of chemical communication to regulate their complex social interactions. Specific proteins involved in odorant detection most likely supported this chemical communication. Odorant reception takes place mainly in the antennae within hairlike structures called olfactory sensilla. Antennal proteomes of sexually mature drone and forager worker bees (an age group of bees assigned to perform field tasks) were compared using two-dimensional electrophoresis, mass spectrometry, quantitative real-time polymerase chain reaction, and bioinformatics. Sixty-one differentially expressed proteins were identified in which 67% were highly upregulated in the drones' antennae whereas only 33% upregulated in the worker bees' antennae. The antennae of the worker bees strongly expressed carbohydrate and energy metabolism and molecular transporters signifying a strong demand for metabolic energy and odorant binding proteins for their foraging activities and other olfactory responses, while proteins related to fatty acid metabolism, antioxidation, and protein folding were strongly upregulated in the drones' antennae as an indication of the importance for the detection and degradation of sex pheromones during queen identification for mating. On the basis of both groups of altered antenna proteins, carbohydrate metabolism and energy production and molecular transporters comprised more than 80% of the functional enrichment analysis and 45% of the constructed biological interaction networks (BIN), respectively. This suggests these two protein families play crucial roles in the antennal olfactory function of sexually mature drone and forager worker bees. Several key node proteins in the BIN were validated at the transcript level. This first global proteomic comparative analysis of antennae reveals sex-biased protein expression in both bees, indicating that odorant response mechanisms are sex-specific because of natural selection for different olfactory

  15. Africanization in the United States: Replacement of Feral European Honeybees (Apis mellifera L.) by an African Hybrid Swarm

    OpenAIRE

    Pinto, M. Alice; Rubink, William L.; Patton, John C.; Coulson, Robert N.; Johnston, J. Spencer

    2005-01-01

    The expansion of Africanized honeybees from South America to the southwestern United States in 50 years is considered one of the most spectacular biological invasions yet documented. In the American tropics, it has been shown that during their expansion Africanized honeybees have low levels of introgressed alleles from resident European populations. In the United States, it has been speculated, but not shown, that Africanized honeybees would hybridize extensively with European ho...

  16. Kin discrimination allows plants to modify investment towards pollinator attraction.

    Science.gov (United States)

    Torices, Rubén; Gómez, José M; Pannell, John R

    2018-05-22

    Pollinators tend to be preferentially attracted to large floral displays that may comprise more than one plant in a patch. Attracting pollinators thus not only benefits individuals investing in advertising, but also other plants in a patch through a 'magnet' effect. Accordingly, there could be an indirect fitness advantage to greater investment in costly floral displays by plants in kin-structured groups than when in groups of unrelated individuals. Here, we seek evidence for this strategy by manipulating relatedness in groups of the plant Moricandia moricandioides, an insect-pollinated herb that typically grows in patches. As predicted, individuals growing with kin, particularly at high density, produced larger floral displays than those growing with non-kin. Investment in attracting pollinators was thus moulded by the presence and relatedness of neighbours, exemplifying the importance of kin recognition in the evolution of plant reproductive strategies.

  17. Enhanced biodiversity and pollination in UK agroforestry systems.

    Science.gov (United States)

    Varah, Alexa; Jones, Hannah; Smith, Jo; Potts, Simon G

    2013-07-01

    Monoculture farming systems have had serious environmental impacts such as loss of biodiversity and pollinator decline. The authors explain how temperate agroforestry systems show potential in being able to deliver multiple environmental benefits. © 2013 Society of Chemical Industry.

  18. 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.

  19. 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

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

    African Journals Online (AJOL)

    STORAGESEVER

    2009-05-04

    May 4, 2009 ... Key words: Apis mellifera adansonii, Vigna unguiculata, bee plant, foraging, pollination, increased yield. INTRODUCTION. There are ... several techniques such as fire-prone, crop rotations, ..... Inventory of melliferous plants.

  1. 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.

  2. Metabolic control of tobacco pollination by sugars and invertases

    DEFF Research Database (Denmark)

    Goetz, Marc; Guivarc'h, Anne; Hirsche, Jörg

    2017-01-01

    that the functional coupling of sucrose cleavage by invertases and uptake of the released hexoses by monosaccharide transporters are critical for pollination in tobacco. Transcript profiling, in situ hybridization and immunolocalization of extracellular invertases and two monosaccharide transporters in vitro...

  3. 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...

  4. 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...... of several species attributes related to pollination syndromes, species phenology, abundance and connectivity in structuring compartmentalization. BM could not identify compartments in our network. By contrast, UM revealed four modules composed of plants and pollinators, and GM four groups of plants and five...... of pollinators. Phenology had a major influence on compartmentalization, and compartments (both UM and GM) had distinct phenophases. Compartments were also strongly characterized by species degree (number of connections) and betweenness centrality. These two attributes were highly related to each other...

  5. 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...

  6. Breeding system and pollination biology of the semi- domesticated ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-11-19

    Nov 19, 2008 ... about the reproductive ecology and population genetics of tamarind. ..... were no significant interaction effects between mode of pollination and .... Evolution of sexual systems in flowering plants. Ann. Missouri Bot. Garden 68: ...

  7. Pollination in the oil palms Elaeis guineensis, E. oleifera and their hybrids (OxG, in tropical America

    Directory of Open Access Journals (Sweden)

    María Raquel Meléndez

    2016-03-01

    Full Text Available Oil palm (Elaeis guineensis is very important in the Central and South American economies. Plants suffer from a devastating fungal disease known as "lethal decay" or "pudrición del cogollo", in Spanish. Producer countries in Africa, Asia and tropical America have developed breeding programs that seek the tolerance of this disease by plants. The hybrids Elaeis guineensis x Elaeis oleifera (OxG are resistant, but show physiological problems that affect commercial productivity. Natural pollination in these hybrids is low and manual pollination has high labor costs. The Coleoptera order is the most numerous and diverse natural pollinator, and the Elaeidobius genus has high efficiency and specificity to oil palm species. Elaeidobius kameronicus, Elaeidobius subvittatus and Mystrops costaricensis are the insects most commonly associated with oil palm inflorescences. Dynamics in insect populations change according to palm species and weather conditions. It is necessary to understand the insect behavior and population dynamics in OxG hybrids. Thus, recent studies on oil palm pollination, insect diversity and distribution in Latin America are discussed in this study.

  8. 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

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

    Science.gov (United States)

    Silva-Neto, C M; Bergamini, L L; Elias, M A S; Moreira, G L; Morais, J M; Bergamini, B A R; Franceschinelli, E V

    2017-01-01

    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 study agroecosystem.

  10. Benefit and cost curves for typical pollination mutualisms.

    Science.gov (United States)

    Morris, William F; Vázquez, Diego P; Chacoff, Natacha P

    2010-05-01

    Mutualisms provide benefits to interacting species, but they also involve costs. If costs come to exceed benefits as population density or the frequency of encounters between species increases, the interaction will no longer be mutualistic. Thus curves that represent benefits and costs as functions of interaction frequency are important tools for predicting when a mutualism will tip over into antagonism. Currently, most of what we know about benefit and cost curves in pollination mutualisms comes from highly specialized pollinating seed-consumer mutualisms, such as the yucca moth-yucca interaction. There, benefits to female reproduction saturate as the number of visits to a flower increases (because the amount of pollen needed to fertilize all the flower's ovules is finite), but costs continue to increase (because pollinator offspring consume developing seeds), leading to a peak in seed production at an intermediate number of visits. But for most plant-pollinator mutualisms, costs to the plant are more subtle than consumption of seeds, and how such costs scale with interaction frequency remains largely unknown. Here, we present reasonable benefit and cost curves that are appropriate for typical pollinator-plant interactions, and we show how they can result in a wide diversity of relationships between net benefit (benefit minus cost) and interaction frequency. We then use maximum-likelihood methods to fit net-benefit curves to measures of female reproductive success for three typical pollination mutualisms from two continents, and for each system we chose the most parsimonious model using information-criterion statistics. We discuss the implications of the shape of the net-benefit curve for the ecology and evolution of plant-pollinator mutualisms, as well as the challenges that lie ahead for disentangling the underlying benefit and cost curves for typical pollination mutualisms.

  11. Memory formation in reversal learning of the honeybee

    Directory of Open Access Journals (Sweden)

    Ravit Hadar

    2010-12-01

    Full Text Available In reversal learning animals are first trained with a differential learning protocol, where they learn to respond to a reinforced odor (CS+ and not to respond to a nonreinforced odor (CS-. Once they respond correctly to this rule, the contingencies of the conditioned stimuli are reversed, and animals learn to adjust their response to the new rule. This study investigated the effect of a protein synthesis inhibitor (emetine on the memory formed after reversal learning in the honeybee Apis mellifera. Two groups of bees were studied: summer bees and winter bees, each yielded different results. Blocking protein synthesis in summer bees inhibits consolidation of the excitatory learning following reversal learning whereas it blocked the consolidation of the inhibitory learning in winter bees. These findings suggest that excitatory and inhibitory learning may involve different molecular processes in bees, which are seasonally dependent.

  12. Conditioning procedure and color discrimination in the honeybee Apis mellifera

    Science.gov (United States)

    Giurfa, Martin

    We studied the influence of the conditioning procedure on color discrimination by free-flying honeybees. We asked whether absolute and differential conditioning result in different discrimination capabilities for the same pairs of colored targets. In absolute conditioning, bees were rewarded on a single color; in differential conditioning, bees were rewarded on the same color but an alternative, non-rewarding, similar color was also visible. In both conditioning procedures, bees learned their respective task and could also discriminate the training stimulus from a novel stimulus that was perceptually different from the trained one. Discrimination between perceptually closer stimuli was possible after differential conditioning but not after absolute conditioning. Differences in attention inculcated by these training procedures may underlie the different discrimination performances of the bees.

  13. 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.

  14. 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.

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

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    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.

  16. Pollination induces autophagy in petunia petals via ethylene.

    Science.gov (United States)

    Shibuya, Kenichi; Niki, Tomoko; Ichimura, Kazuo

    2013-02-01

    Autophagy is one of the main mechanisms of degradation and remobilization of macromolecules, and it appears to play an important role in petal senescence. However, little is known about the regulatory mechanisms of autophagy in petal senescence. Autophagic processes were observed by electron microscopy and monodansylcadaverine staining of senescing petals of petunia (Petunia hybrida); autophagy-related gene 8 (ATG8) homologues were isolated from petunia and the regulation of expression was analysed. Nutrient remobilization was also examined during pollination-induced petal senescence. Active autophagic processes were observed in the mesophyll cells of senescing petunia petals. Pollination induced the expression of PhATG8 homologues and was accompanied by an increase in ethylene production. Ethylene inhibitor treatment in pollinated flowers delayed the induction of PhATG8 homologues, and ethylene treatment rapidly upregulated PhATG8 homologues in petunia petals. Dry weight and nitrogen content were decreased in the petals and increased in the ovaries after pollination in detached flowers. These results indicated that pollination induces autophagy and that ethylene is a key regulator of autophagy in petal senescence of petunia. The data also demonstrated the translocation of nutrients from the petals to the ovaries during pollination-induced petal senescence.

  17. PROTEINS OF THE INTEGUMENTARY SYSTEM OF THE HONEYBEE, Apis mellifera.

    Science.gov (United States)

    Micas, André Fernando Ditondo; Ferreira, Germano Aguiar; Laure, Helen Julie; Rosa, José Cesar; Bitondi, Márcia Maria Gentile

    2016-09-01

    The integument of insects and other arthropods is composed of an inner basal lamina coated by the epidermis, which secretes the bulk of the outer integument layer, the cuticle. The genome sequencing of several insect species has allowed predicting classes of proteins integrating the cuticle. However, only a small proportion of them, as well as other proteins in the integumentary system, have been validated. Using two-dimensional gel electrophoresis coupled with mass spectrometry, we identified 45 different proteins in a total of 112 selected gel spots derived from thoracic integument samples of developing honeybee workers, including 14 cuticular proteins (AmelCPR 3, AmelCPR 12, AmelCPR 16, AmelCPR 27, apidermin 2, apidermin 3, endocuticle structural glycoprotein SgAbd-8-like, LOC100577363, LOC408365, LOC413679, LOC725454, LOC100576916, LOC725838, and peritrophin 3-C analogous). Gene ontology functional analysis revealed that the higher proportions of the identified proteins have molecular functions related to catalytic and structural molecule activities, are involved in metabolic biological processes, and pertain to the protein class of structural or cytoskeletal proteins and hydrolases. It is noteworthy that 26.7% of the identified proteins, including five cuticular proteins, were revealed as protein species resulting from allelic isoforms or derived from posttranslational modifications. Also, 66.7% of the identified cuticular proteins were expressed in more than one developmental phase, thus indicating that they are part of the larval, pupal, and adult cuticle. Our data provide experimental support for predicted honeybee gene products and new information on proteins expressed in the developing integument. © 2016 Wiley Periodicals, Inc.

  18. Widespread exploitation of the honeybee by early Neolithic farmers.

    Science.gov (United States)

    Roffet-Salque, Mélanie; Regert, Martine; Evershed, Richard P; Outram, Alan K; Cramp, Lucy J E; Decavallas, Orestes; Dunne, Julie; Gerbault, Pascale; Mileto, Simona; Mirabaud, Sigrid; Pääkkönen, Mirva; Smyth, Jessica; Šoberl, Lucija; Whelton, Helen L; Alday-Ruiz, Alfonso; Asplund, Henrik; Bartkowiak, Marta; Bayer-Niemeier, Eva; Belhouchet, Lotfi; Bernardini, Federico; Budja, Mihael; Cooney, Gabriel; Cubas, Miriam; Danaher, Ed M; Diniz, Mariana; Domboróczki, László; Fabbri, Cristina; González-Urquijo, Jesus E; Guilaine, Jean; Hachi, Slimane; Hartwell, Barrie N; Hofmann, Daniela; Hohle, Isabel; Ibáñez, Juan J; Karul, Necmi; Kherbouche, Farid; Kiely, Jacinta; Kotsakis, Kostas; Lueth, Friedrich; Mallory, James P; Manen, Claire; Marciniak, Arkadiusz; Maurice-Chabard, Brigitte; Mc Gonigle, Martin A; Mulazzani, Simone; Özdoğan, Mehmet; Perić, Olga S; Perić, Slaviša R; Petrasch, Jörg; Pétrequin, Anne-Marie; Pétrequin, Pierre; Poensgen, Ulrike; Pollard, C Joshua; Poplin, François; Radi, Giovanna; Stadler, Peter; Stäuble, Harald; Tasić, Nenad; Urem-Kotsou, Dushka; Vuković, Jasna B; Walsh, Fintan; Whittle, Alasdair; Wolfram, Sabine; Zapata-Peña, Lydia; Zoughlami, Jamel

    2015-11-12

    The pressures on honeybee (Apis mellifera) populations, resulting from threats by modern pesticides, parasites, predators and diseases, have raised awareness of the economic importance and critical role this insect plays in agricultural societies across the globe. However, the association of humans with A. mellifera predates post-industrial-revolution agriculture, as evidenced by the widespread presence of ancient Egyptian bee iconography dating to the Old Kingdom (approximately 2400 BC). There are also indications of Stone Age people harvesting bee products; for example, honey hunting is interpreted from rock art in a prehistoric Holocene context and a beeswax find in a pre-agriculturalist site. However, when and where the regular association of A. mellifera with agriculturalists emerged is unknown. One of the major products of A. mellifera is beeswax, which is composed of a complex suite of lipids including n-alkanes, n-alkanoic acids and fatty acyl wax esters. The composition is highly constant as it is determined genetically through the insect's biochemistry. Thus, the chemical 'fingerprint' of beeswax provides a reliable basis for detecting this commodity in organic residues preserved at archaeological sites, which we now use to trace the exploitation by humans of A. mellifera temporally and spatially. Here we present secure identifications of beeswax in lipid residues preserved in pottery vessels of Neolithic Old World farmers. The geographical range of bee product exploitation is traced in Neolithic Europe, the Near East and North Africa, providing the palaeoecological range of honeybees during prehistory. Temporally, we demonstrate that bee products were exploited continuously, and probably extensively in some regions, at least from the seventh millennium cal BC, likely fulfilling a variety of technological and cultural functions. The close association of A. mellifera with Neolithic farming communities dates to the early onset of agriculture and may provide

  19. Vibration-processing interneurons in the honeybee brain

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    Hiroyuki Ai

    2010-01-01

    Full Text Available The afferents of the Johnston’s organ (JO in the honeybee brain send their axons to three distinct areas, the dorsal lobe, the dorsal subesophageal ganglion (DL-dSEG, and the posterior protocerebral lobe (PPL, suggesting that vibratory signals detected by the JO are processed differentially in these primary sensory centers. The morphological and physiological characteristics of interneurons arborizing in these areas were studied by intracellular recording and staining. DL-Int-1 and DL-Int-2 have dense arborizations in the DL-dSEG and respond to vibratory stimulation applied to the JO in either tonic excitatory, on-off-phasic excitatory, or tonic inhibitory patterns. PPL-D-1 has dense arborizations in the PPL, sends axons into the ventral nerve cord (VNC, and responds to vibratory stimulation and olfactory stimulation simultaneously applied to the antennae in long-lasting excitatory pattern. These results show that there are at least two parallel pathways for vibration processing through the DL-dSEG and the PPL. In this study, Honeybee Standard Brain was used as the common reference, and the morphology of two types of interneurons (DL-Int-1 and DL-Int-2 and JO afferents was merged into the standard brain based on the boundary of several neuropiles, greatly supporting the understanding of the spatial relationship between these identified neurons and JO afferents. The visualization of the region where the JO afferents are closely appositioned to these DL interneurons demonstrated the difference in putative synaptic regions between the JO afferents and these DL interneurons (DL-Int-1 and DL-Int-2 in the DL. The neural circuits related to the vibration-processing interneurons are discussed.

  20. Social waves in giant honeybees (Apis dorsata) elicit nest vibrations.

    Science.gov (United States)

    Kastberger, Gerald; Weihmann, Frank; Hoetzl, Thomas

    2013-07-01

    Giant honeybees (Apis dorsata) nest in the open and have developed a wide array of strategies for colony defence, including the Mexican wave-like shimmering behaviour. In this collective response, the colony members perform upward flipping of their abdomens in coordinated cascades across the nest surface. The time-space properties of these emergent waves are response patterns which have become of adaptive significance for repelling enemies in the visual domain. We report for the first time that the mechanical impulse patterns provoked by these social waves and measured by laser Doppler vibrometry generate vibrations at the central comb of the nest at the basic (='natural') frequency of 2.156 ± 0.042 Hz which is more than double the average repetition rate of the driving shimmering waves. Analysis of the Fourier spectra of the comb vibrations under quiescence and arousal conditions provoked by mass flight activity and shimmering waves gives rise to the proposal of two possible models for the compound physical system of the bee nest: According to the elastic oscillatory plate model, the comb vibrations deliver supra-threshold cues preferentially to those colony members positioned close to the comb. The mechanical pendulum model predicts that the comb vibrations are sensed by the members of the bee curtain in general, enabling mechanoreceptive signalling across the nest, also through the comb itself. The findings show that weak and stochastic forces, such as general quiescence or diffuse mass flight activity, cause a harmonic frequency spectrum of the comb, driving the comb as an elastic plate. However, shimmering waves provide sufficiently strong forces to move the nest as a mechanical pendulum. This vibratory behaviour may support the colony-intrinsic information hypothesis herein that the mechanical vibrations of the comb provoked by shimmering do have the potential to facilitate immediate communication of the momentary defensive state of the honeybee nest to

  1. Social waves in giant honeybees ( Apis dorsata) elicit nest vibrations

    Science.gov (United States)

    Kastberger, Gerald; Weihmann, Frank; Hoetzl, Thomas

    2013-07-01

    Giant honeybees ( Apis dorsata) nest in the open and have developed a wide array of strategies for colony defence, including the Mexican wave-like shimmering behaviour. In this collective response, the colony members perform upward flipping of their abdomens in coordinated cascades across the nest surface. The time-space properties of these emergent waves are response patterns which have become of adaptive significance for repelling enemies in the visual domain. We report for the first time that the mechanical impulse patterns provoked by these social waves and measured by laser Doppler vibrometry generate vibrations at the central comb of the nest at the basic (=`natural') frequency of 2.156 ± 0.042 Hz which is more than double the average repetition rate of the driving shimmering waves. Analysis of the Fourier spectra of the comb vibrations under quiescence and arousal conditions provoked by mass flight activity and shimmering waves gives rise to the proposal of two possible models for the compound physical system of the bee nest: According to the elastic oscillatory plate model, the comb vibrations deliver supra-threshold cues preferentially to those colony members positioned close to the comb. The mechanical pendulum model predicts that the comb vibrations are sensed by the members of the bee curtain in general, enabling mechanoreceptive signalling across the nest, also through the comb itself. The findings show that weak and stochastic forces, such as general quiescence or diffuse mass flight activity, cause a harmonic frequency spectrum of the comb, driving the comb as an elastic plate. However, shimmering waves provide sufficiently strong forces to move the nest as a mechanical pendulum. This vibratory behaviour may support the colony-intrinsic information hypothesis herein that the mechanical vibrations of the comb provoked by shimmering do have the potential to facilitate immediate communication of the momentary defensive state of the honeybee nest to the

  2. A Mathematical Model of Intra-Colony Spread of American Foulbrood in European Honeybees (Apis mellifera L..

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    Eduardo O Jatulan

    Full Text Available American foulbrood (AFB is one of the severe infectious diseases of European honeybees (Apis mellifera L. and other Apis species. This disease is caused by a gram-positive, spore-forming bacterium Paenibacillus larvae. In this paper, a compartmental (SI framework model is constructed to represent the spread of AFB within a colony. The model is analyzed to determine the long-term fate of the colony once exposed to AFB spores. It was found out that without effective and efficient treatment, AFB infection eventually leads to colony collapse. Furthermore, infection thresholds were predicted based on the stability of the equilibrium states. The number of infected cell combs is one of the factors that drive disease spread. Our results can be used to forecast the transmission timeline of AFB infection and to evaluate the control strategies for minimizing a possible epidemic.

  3. Sit-and-wait pollination in the spring flowering woodland plant, Trillium grandiflorum

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    Barrett, Spencer C.H.

    2011-07-01

    Full Text Available In animal-pollinated plants, reproductive success is commonly limited by pollen availability, which can occur in environments where pollinator activity is scarce or variable. Extended floral longevity to maximize a plant’s access to pollinators may be an adaptation to such uncertain pollination environments. Here, we investigated the effects of flower exposure time to pollinators on female fertility (fruit and seed set in the bee-pollinated woodland herb Trillium grandiflorum, a species with long-lived flowers (~17-21 d that blooms in early spring when pollinator activity is often variable. We experimentally exposed flowers to pollinators for different amounts of time to determine the extent to which floral longevity influenced reproductive success. The amount of time that flowers were exposed to pollinators significantly increased fruit set and seed set per flower, but not seed set per fruit. Our results provide experimental evidence that long floral life spans may function as a ‘sit-and-wait’ pollination strategy to increase the amount of exposure time to pollinators and promote seed set in the unpredictable pollination environments often experienced by early spring ephemerals. In large populations with infrequent pollinator visitation, as commonly occurs in T. grandiflorum, pollination may be a largely stochastic process.

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

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    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.

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

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    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.

  6. It Takes Two – Coincidence coding within the dual olfactory pathway of the honeybee

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    Martin F. Brill

    2015-07-01

    Full Text Available To rapidly process biologically relevant stimuli, sensory systems have developed a broad variety of coding mechanisms like parallel processing and coincidence detection. Parallel processing (e.g. in the visual system, increases both computational capacity and processing speed by simultaneously coding different aspects of the same stimulus. Coincidence detection is an efficient way to integrateinformation from different sources. Coincidence has been shown to promote associative learning and memory or stimulus feature detection (e.g. in auditory delay lines. Within the dual olfactory pathway of the honeybee both of these mechanisms might be implemented by uniglomerular projection neurons (PNs that transfer information from the primary olfactory centers, the antennal lobe (AL, to a multimodal integration center, the mushroom body (MB. PNs from anatomically distinct tracts respond to the same stimulus space, but have different physiological properties, characteristics that are prerequisites for parallel processing of different stimulus aspects. However, the PN pathways also display mirror-imaged like anatomical trajectories that resemble neuronal coincidence detectors as known from auditory delay lines. To investigate temporal processing of olfactory information, we recorded PN odor responses simultaneously from both tracts and measured coincident activity of PNs within and between tracts. Our results show that coincidence levels are different within each of the two tracts. Coincidence also occurs between tracts, but to a minor extent compared to coincidence within tracts. Taken together our findings support the relevance of spike timing in coding of olfactory information (temporal code.

  7. It takes two-coincidence coding within the dual olfactory pathway of the honeybee.

    Science.gov (United States)

    Brill, Martin F; Meyer, Anneke; Rössler, Wolfgang

    2015-01-01

    To rapidly process biologically relevant stimuli, sensory systems have developed a broad variety of coding mechanisms like parallel processing and coincidence detection. Parallel processing (e.g., in the visual system), increases both computational capacity and processing speed by simultaneously coding different aspects of the same stimulus. Coincidence detection is an efficient way to integrate information from different sources. Coincidence has been shown to promote associative learning and memory or stimulus feature detection (e.g., in auditory delay lines). Within the dual olfactory pathway of the honeybee both of these mechanisms might be implemented by uniglomerular projection neurons (PNs) that transfer information from the primary olfactory centers, the antennal lobe (AL), to a multimodal integration center, the mushroom body (MB). PNs from anatomically distinct tracts respond to the same stimulus space, but have different physiological properties, characteristics that are prerequisites for parallel processing of different stimulus aspects. However, the PN pathways also display mirror-imaged like anatomical trajectories that resemble neuronal coincidence detectors as known from auditory delay lines. To investigate temporal processing of olfactory information, we recorded PN odor responses simultaneously from both tracts and measured coincident activity of PNs within and between tracts. Our results show that coincidence levels are different within each of the two tracts. Coincidence also occurs between tracts, but to a minor extent compared to coincidence within tracts. Taken together our findings support the relevance of spike timing in coding of olfactory information (temporal code).

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

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    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.

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

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    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

  10. 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

  11. 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.

  12. 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.

  13. Population Genetic Aspects of Pollinator Decline

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    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.

  14. 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.

  15. 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

  16. Climate-associated phenological advances in bee pollinators and bee-pollinated plants

    Science.gov (United States)

    Bartomeus, Ignasi; Ascher, John S.; Wagner, David; Danforth, Bryan N.; Colla, Sheila; Kornbluth, Sarah; Winfree, Rachael

    2011-01-01

    The phenology of many ecological processes is modulated by temperature, making them potentially sensitive to climate change. Mutualistic interactions may be especially vulnerable because of the potential for phenological mismatching if the species involved do not respond similarly to changes in temperature. Here we present an analysis of climate-associated shifts in the phenology of wild bees, the most important pollinators worldwide, and compare these shifts to published studies of bee-pollinated plants over the same time period. We report that over the past 130 y, the phenology of 10 bee species from northeastern North America has advanced by a mean of 10.4 ± 1.3 d. Most of this advance has taken place since 1970, paralleling global temperature increases. When the best available data are used to estimate analogous rates of advance for plants, these rates are not distinguishable from those of bees, suggesting that bee emergence is keeping pace with shifts in host-plant flowering, at least among the generalist species that we investigated. PMID:22143794

  17. Potential pollinators of Comolia ovalifolia DC Triana (Melastomataceae) and Chamaecrista ramosa (Vog.) H.S. Irwin and Barneby var. ramosa (Leguminosae-Caesalpinioideae), in restinga, Bahia, Brazil.

    Science.gov (United States)

    Oliveira-Rebouças, P; Gimenes, M

    2011-05-01

    Comolia ovalifolia DC Triana (Melastomataceae) and Chamaecrista ramosa (Vog.) H.S. Irwin and Barneby var. ramosa (Leguminosae-Caesalpinioideae) are tropical plant species found in restinga (herbaceous-shrubby, sandy costal ecosystems). They have flowers with poricidal anthers and are pollinated by bees. The study sought to analyse potential pollinators of both plants during visits to their flowers in a restinga area in Bahia. The flowering displayed by both species was considered continuous and long duration, constantly providing pollen to floral visitors. C. ovalifolia was visited by 17 species of bees and C. ramosa by 16 species, predominantly from the Apidae family (with a similarity index of 74%). The behavior displayed by these visiting bees was of vibrating anthers. The small-sized Euglossa sp. Latreille, 1802 and Florilegus similis Urban, 1970 bees played less of a role as pollinators, since they rarely touched the flower stigma during harvests and were thus considered opportunist visitors or casual pollinators. Centris decolorata Lepetier, 1841 (= C. leprieuri) and Xylocopa subcyanea Perez, 1901 are large bees and were considered efficient pollinators of C. ovalifolia and C. ramosa because of the higher frequency and constancy of their visits, and their favourable behaviour and size for pollen transfer between flowers, which guarantees the survival of these native restinga plant species.

  18. 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

  19. Relative stability of core groups in pollination networks in a biodiversity hotspot over four years.

    Science.gov (United States)

    Fang, Qiang; Huang, Shuang-Quan

    2012-01-01

    Plants and their pollinators form pollination networks integral to the evolution and persistence of species in communities. Previous studies suggest that pollination network structure remains nested while network composition is highly dynamic. However, little is known about temporal variation in the structure and function of plant-pollinator networks, especially in species-rich communities where the strength of pollinator competition is predicted to be high. Here we quantify temporal variation of pollination networks over four consecutive years in an alpine meadow in the Hengduan Mountains biodiversity hotspot in China. We found that ranked positions and idiosyncratic temperatures of both plants and pollinators were more conservative between consecutive years than in non-consecutive years. Although network compositions exhibited high turnover, generalized core groups--decomposed by a k-core algorithm--were much more stable than peripheral groups. Given the high rate of turnover observed, we suggest that identical plants and pollinators that persist for at least two successive years sustain pollination services at the community level. Our data do not support theoretical predictions of a high proportion of specialized links within species-rich communities. Plants were relatively specialized, exhibiting less variability in pollinator composition at pollinator functional group level than at the species level. Both specialized and generalized plants experienced narrow variation in functional pollinator groups. The dynamic nature of pollination networks in the alpine meadow demonstrates the potential for networks to mitigate the effects of fluctuations in species composition in a high biodiversity area.

  20. Competition for pollinators and intra-communal spectral dissimilarity of flowers.

    Science.gov (United States)

    van der Kooi, C J; Pen, I; Staal, M; Stavenga, D G; Elzenga, J T M

    2016-01-01

    Competition for pollinators occurs when, in a community of flowering plants, several simultaneously flowering plant species depend on the same pollinator. Competition for pollinators increases interspecific pollen transfer rates, thereby reducing the number of viable offspring. In order to decrease interspecific pollen transfer, plant species can distinguish themselves from competitors by having a divergent phenotype. Floral colour is an important signalling cue to attract potential pollinators and thus a major aspect of the flower phenotype. In this study, we analysed the amount of spectral dissimilarity of flowers among pollinator-competing plants in a Dutch nature reserve. We expected pollinator-competing plants to exhibit more spectral dissimilarity than non-competing plants. Using flower visitation data of 2 years, we determined the amount of competition for pollinators by different plant species. Plant species that were visited by the same pollinator were considered specialist and competing for that pollinator, whereas plant species visited by a broad array of pollinators were considered non-competing generalists. We used principal components analysis to quantify floral reflectance, and found evidence for enhanced spectral dissimilarity among plant species within specialist pollinator guilds (i.e. groups of plant species competing for the same pollinator). This is the first study that examined intra-communal dissimilarity in floral reflectance with a focus on the pollination system. © 2015 German Botanical Society and The Royal Botanical Society of the Netherlands.

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

    Directory of Open Access Journals (Sweden)

    Ana Maria Franco

    2011-09-01

    Full Text Available Pollinator guild organization and its consequences for reproduction in three synchronopatric species of Tibouchina (Melastomataceae. In co-flowering plant species, pollinator sharing can result in interspecific pollen transfer and fecundity reduction. Competition will be relaxed whenever there is a large amount of initial pollen supply or if each plant species occupies different habitat patches. Reproduction in Tibouchina cerastifolia (Naudin Cogn., T. clinopodifolia (DC. Cogn. and T. gracilis (Bonpl. Cogn. was studied in an area of Atlantic rainforest to examine whether synchronopatry induces time partitioning among pollinator species. Eleven bee species comprised the pollinator guild. Among pollinators, there were overlaps in bee species composition and in flower visitation time. Direct competition for pollen in Tibouchina Aubl. at the study site seems to lead to different activity periods among the bee species, in which Bombus pauloensis Friese,1913 was most active earlier, while the other species were active later in the day. Bombus pauloensis, the largest bee species recorded on Tibouchina flowers, was the most important and efficient pollinator. This species harvested pollen before the other species and had the shortest handling time. The plants reproduced sexually by selfing or outcrossing, and hybridization was not avoided by incompatibility reactions at the style. The avoidance of direct competition for pollen and no pollinator partitioning among the synchronopatric species of Tibouchina may reflect a facilitative interaction among these pioneer plants.Organização da guilda de polinizadores e sua consequência para reprodução em três espécies sincropátricas de Tibouchina (Melastomataceae. Em espécies de plantas que co-florescem, a partilha de polinizadores pode resultar em transferência interespecífica de pólen e redução da fecundidade. A competição pode ser relaxada quando existe uma grande quantidade de suprimento de p

  2. Beehold : the colony of the honeybee (Apis mellifera L) as a bio-sampler for pollutants and plant pathogens

    NARCIS (Netherlands)

    Steen, van der J.J.M.

    2016-01-01

    Bio-sampling is a function of bio-indication. Bio-indication with honeybee colonies (Apis mellifera L) is where the research fields of environmental technology and apiculture overlap. The honeybees are samplers of the environment by collecting unintentionally and simultaneously, along

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

    Directory of Open Access Journals (Sweden)

    Maria Cristina Gaglianone

    2013-10-01

    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.

  4. 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.

  5. Comparative psychophysics of bumblebee and honeybee colour discrimination and object detection.

    Science.gov (United States)

    Dyer, Adrian G; Spaethe, Johannes; Prack, Sabina

    2008-07-01

    Bumblebee (Bombus terrestris) discrimination of targets with broadband reflectance spectra was tested using simultaneous viewing conditions, enabling an accurate determination of the perceptual limit of colour discrimination excluding confounds from memory coding (experiment 1). The level of colour discrimination in bumblebees, and honeybees (Apis mellifera) (based upon previous observations), exceeds predictions of models considering receptor noise in the honeybee. Bumblebee and honeybee photoreceptors are similar in spectral shape and spacing, but bumblebees exhibit significantly poorer colour discrimination in behavioural tests, suggesting possible differences in spatial or temporal signal processing. Detection of stimuli in a Y-maze was evaluated for bumblebees (experiment 2) and honeybees (experiment 3). Honeybees detected stimuli containing both green-receptor-contrast and colour contrast at a visual angle of approximately 5 degrees , whilst stimuli that contained only colour contrast were only detected at a visual angle of 15 degrees . Bumblebees were able to detect these stimuli at a visual angle of 2.3 degrees and 2.7 degrees , respectively. A comparison of the experiments suggests a tradeoff between colour discrimination and colour detection in these two species, limited by the need to pool colour signals to overcome receptor noise. We discuss the colour processing differences and possible adaptations to specific ecological habitats.

  6. 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.

  7. 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.

  8. western honey bee management for crop pollination abstract résumé

    African Journals Online (AJOL)

    ACSS

    2018-02-09

    Feb 9, 2018 ... of Western honey bee for pollination services is reported mainly in developed countries. Because ... plants, or accumulating in nectar and pollen that affect ..... Ecology and Evolution .... Pollinator interactions in the Neotropics.

  9. 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...

  10. Radiation of pollination systems in the Iridaceae of sub-Saharan Africa.

    Science.gov (United States)

    Goldblatt, Peter; Manning, John C

    2006-03-01

    Seventeen distinct pollination systems are known for genera of sub-Saharan African Iridaceae and recurrent shifts in pollination system have evolved in those with ten or more species. Pollination by long-tongued anthophorine bees foraging for nectar and coincidentally acquiring pollen on some part of their bodies is the inferred ancestral pollination strategy for most genera of the large subfamilies Iridoideae and Crocoideae and may be ancestral for the latter. Derived strategies include pollination by long-proboscid flies, large butterflies, night-flying hovering and settling moths, hopliine beetles and sunbirds. Bee pollination is diverse, with active pollen collection by female bees occurring in several genera, vibratile systems in a few and non-volatile oil as a reward in one species. Long-proboscid fly pollination, which is apparently restricted to southern Africa, includes four separate syndromes using different sets of flies and plant species in different parts of the subcontinent. Small numbers of species use bibionid flies, short-proboscid flies or wasps for their pollination; only about 2 % of species use multiple pollinators and can be described as generalists. Using pollination observations for 375 species and based on repeated patterns of floral attractants and rewards, we infer pollination mechanisms for an additional 610 species. Matching pollination system to phylogeny or what is known about species relationships based on shared derived features, we infer repeated shifts in pollination system in some genera, as frequently as one shift for every five or six species of southern African Babiana or Gladiolus. Specialized systems using pollinators of one pollination group, or even a single pollinator species are the rule in the family. Shifts in pollination system are more frequent in genera of Crocoideae that have bilaterally symmetric flowers and a perianth tube, features that promote adaptive radiation by facilitating precise shifts in pollen

  11. Exposure to Sublethal Doses of Fipronil and Thiacloprid Highly Increases Mortality of Honeybees Previously Infected by Nosema ceranae

    Science.gov (United States)

    Vidau, Cyril; Diogon, Marie; Aufauvre, Julie; Fontbonne, Régis; Viguès, Bernard; Brunet, Jean-Luc; Texier, Catherine; Biron, David G.; Blot, Nicolas; El Alaoui, Hicham; Belzunces, Luc P.; Delbac, Frédéric

    2011-01-01

    Background The honeybee, Apis mellifera, is undergoing a worldwide decline whose origin is still in debate. Studies performed for twenty years suggest that this decline may involve both infectious diseases and exposure to pesticides. Joint action of pathogens and chemicals are known to threaten several organisms but the combined effects of these stressors were poorly investigated in honeybees. Our study was designed to explore the effect of Nosema ceranae infection on honeybee sensitivity to sublethal doses of the insecticides fipronil and thiacloprid. Methodology/Finding Five days after their emergence, honeybees were divided in 6 experimental groups: (i) uninfected controls, (ii) infected with N. ceranae, (iii) uninfected and exposed to fipronil, (iv) uninfected and exposed to thiacloprid, (v) infected with N. ceranae and exposed 10 days post-infection (p.i.) to fipronil, and (vi) infected with N. ceranae and exposed 10 days p.i. to thiacloprid. Honeybee mortality and insecticide consumption were analyzed daily and the intestinal spore content was evaluated 20 days after infection. A significant increase in honeybee mortality was observed when N. ceranae-infected honeybees were exposed to sublethal doses of insecticides. Surprisingly, exposures to fipronil and thiacloprid had opposite effects on microsporidian spore production. Analysis of the honeybee detoxification system 10 days p.i. showed that N. ceranae infection induced an increase in glutathione-S-transferase activity in midgut and fat body but not in 7-ethoxycoumarin-O-deethylase activity. Conclusions/Significance After exposure to sublethal doses of fipronil or thiacloprid a higher mortality was observed in N. ceranae-infected honeybees than in uninfected ones. The synergistic effect of N. ceranae and insecticide on honeybee mortality, however, did not appear strongly linked to a decrease of the insect detoxification system. These data support the hypothesis that the combination of the increasing

  12. Landscape alteration and habitat modification: impacts on plant-pollinator systems

    OpenAIRE

    Vanbergen, Adam J.

    2014-01-01

    Insect pollinators provide an important ecosystem service to many crop species and underpin the reproductive assurance of many wild plant species. Multiple, anthropogenic pressures threaten insect pollinators. Land-use change and intensification alters the habitats and landscapes that provide food and nesting resources for pollinators. These impacts vary according to species traits, producing winners and losers, while the intrinsic robustness of plant-pollinator networks may provide stability...

  13. 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.

  14. Pollination biology in a tropical high-altitude grassland in Brazil: Interactions at the community level

    OpenAIRE

    Freitas, L; Sazima, M

    2006-01-01

    Surveys of local assemblages of plants and their pollinators are among the most useful ways to evaluate specialization in pollination and to discuss the patterns of plant-pollinator interactions among ecosystems. The high-altitude grasslands from southeastern Brazil constitute diminutive island-like formations surrounded by montane rainforests. We registered the floral traits of 124 species from the Serra da Bricaina grasslands (about 60% of the animal-pollinated species of this flora), and d...

  15. Diurnal and Nocturnal Pollination of Marginatocereus marginatus (Pachycereeae: Cactaceae) in Central Mexico

    Science.gov (United States)

    DAR, SALEEM; ARIZMENDI, Ma. del CORO; VALIENTE-BANUET, ALFONSO

    2006-01-01

    • Background and Aims Chiropterophillous and ornithophillous characteristics can form part of a single reproductive strategy in plants that have flowers with diurnal and nocturnal anthesis. This broader pollination strategy can ensure seed set when pollinators are scarce or unpredictable. This appears to be true of hummingbirds, which presumably pollinate Marginatocereus marginatus, a columnar cactus with red nocturnal and diurnal flowers growing as part of dense bat-pollinated columnar cacti forests in arid regions of central Mexico. The aim of this study was to study the floral biology of M. marginatus, and evaluate the effectiveness of nocturnal vs. diurnal pollinators and the contribution of each pollinator group to overall plant fitness. • Methods Individual flower buds were marked and followed to evaluate flower phenology and anthesis time. Flowers and nectar production were measured. An exclusion experiment was conducted to measure the relative contribution of nocturnal and diurnal pollinators to seed set. • Key Results Marginatocereus marginatus has red hermaphroditic flowers with nocturnal and diurnal anthesis. The plant cannot produce seeds by selfing and was pollinated during the day by hummingbirds and during the night by bats, demonstrating that both pollinator groups were important for plant reproduction. Strong pollen limitation was found in the absence of one of the pollinator guilds. • Conclusions Marginatocereus marginatus has an open pollination system in which both diurnal and nocturnal pollinators are needed to set seeds. This represents a fail-safe pollination system that can ensure both pollination, in a situation of low abundance of one of the pollinator groups (hummingbirds), and high competition for nocturnal pollinators with other columnar cacti that bloom synchronously with M. marginatus in the Tehuacan Valley, Mexico. PMID:16394025

  16. 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...

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

    OpenAIRE

    Devaux, Christian; Lepers, C.; Porcher, E.

    2014-01-01

    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 specie...

  18. Plant diversity increases spatio?temporal niche complementarity in plant?pollinator interactions

    OpenAIRE

    Venjakob, Christine; Klein, Alexandra?Maria; Ebeling, Anne; Tscharntke, Teja; Scherber, Christoph

    2016-01-01

    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...

  19. From honeybees to Internet servers: biomimicry for distributed management of Internet hosting centers.

    Science.gov (United States)

    Nakrani, Sunil; Tovey, Craig

    2007-12-01

    An Internet hosting center hosts services on its server ensemble. The center must allocate servers dynamically amongst services to maximize revenue earned from hosting fees. The finite server ensemble, unpredictable request arrival behavior and server reallocation cost make server allocation optimization difficult. Server allocation closely resembles honeybee forager allocation amongst flower patches to optimize nectar influx. The resemblance inspires a honeybee biomimetic algorithm. This paper describes details of the honeybee self-organizing model in terms of information flow and feedback, analyzes the homology between the two problems and derives the resulting biomimetic algorithm for hosting centers. The algorithm is assessed for effectiveness and adaptiveness by comparative testing against benchmark and conventional algorithms. Computational results indicate that the new algorithm is highly adaptive to widely varying external environments and quite competitive against benchmark assessment algorithms. Other swarm intelligence applications are briefly surveyed, and some general speculations are offered regarding their various degrees of success.

  20. Short-sighted evolution of virulence in parasitic honeybee workers ( Apis mellifera capensis Esch.)

    Science.gov (United States)

    Moritz, Robin F. A.; Pirk, Christian W. W.; Hepburn, H. Randall; Neumann, Peter

    2008-06-01

    The short-sighted selection hypothesis for parasite virulence predicts that winners of within-host competition are poorer at transmission to new hosts. Social parasitism by self-replicating, female-producing workers occurs in the Cape honeybee Apis mellifera capensis, and colonies of other honeybee subspecies are susceptible hosts. We found high within-host virulence but low transmission rates in a clone of social parasitic A. m. capensis workers invading the neighbouring subspecies A. m. scutellata. In contrast, parasitic workers from the endemic range of A. m. capensis showed low within-host virulence but high transmission rates. This suggests a short-sighted selection scenario for the host-parasite co-evolution in the invasive range of the Cape honeybee, probably facilitated by beekeeping-assisted parasite transmission in apiaries.

  1. Chemical Composition of Different Botanical Origin Honeys Produced by Sicilian Black Honeybees (Apis mellifera ssp. sicula).

    Science.gov (United States)

    Mannina, Luisa; Sobolev, Anatoly P; Di Lorenzo, Arianna; Vista, Silvia; Tenore, Gian Carlo; Daglia, Maria

    2015-07-01

    In 2008 a Slow Food Presidium was launched in Sicily (Italy) for an early warning of the risk of extinction of the Sicilian native breed of black honeybee (Apis mellifera L. ssp sicula). Today, the honey produced by these honeybees is the only Sicilian honey produced entirely by the black honeybees. In view of few available data regarding the chemical composition of A. mellifera ssp. sicula honeys, in the present investigation the chemical compositions of sulla honey (Hedysarum coronarium L.) and dill honey (Anethum graveolens L.) were studied with a multimethodological approach, which consists of HPLC-PDA-ESI-MSn and NMR spectroscopy. Moreover, three unifloral honeys (lemon honey (obtained from Citrus limon (L.) Osbeck), orange honey (Citrus arantium L.), and medlar honey (Eriobotrya japonica (Thunb.) Lindl)), with known phenol and polyphenol compositions, were studied with NMR spectroscopy to deepen the knowledge about sugar and amino acid compositions.

  2. Rain forest provides pollinating beetles for atemoya crops.

    Science.gov (United States)

    Blanche, Rosalind; Cunningham, Saul A

    2005-08-01

    Small beetles, usually species of Nitidulidae, are the natural pollinators of atemoya (Annona squamosa L. x A. cherimola Mill. hybrids; custard apple) flowers but commercial atemoya growers often need to carry out labor-intensive hand pollination to produce enough high-quality fruit. Because Australian rain forest has plant species in the same family as atemoya (Annonaceae) and because many rain forest plants are beetle pollinated, we set out to discover whether tropical rain forest in far north Queensland harbors beetles that could provide this ecosystem service for atemoya crops. Orchards were chosen along a gradient of increasing distance from tropical rain forest (0.1-24 km). We sampled 100 flowers from each of nine atemoya orchards and determined the identity and abundance of insects within each flower. To assess the amount of pollination due to insects, we bagged six flowers per tree and left another six flowers per tree accessible to insects on 10 trees at an orchard near rain forest. Results indicated that atemoya orchards pollinators that are likely to originate in tropical rain forest. These native beetles occurred reliably enough in crops near rain forest to have a positive effect on the quantity of fruit produced but their contribution was not great enough to satisfy commercial production needs. Management changes, aimed at increasing native beetle abundance in crops, are required before these beetles could eliminate the need for growers to hand pollinate atemoya flowers. Appreciation of the value of this resource is necessary if we are to develop landscapes that both conserve native biodiversity and support agricultural production.

  3. Drought, pollen and nectar availability, and pollination success.

    Science.gov (United States)

    Waser, Nickolas M; Price, Mary V

    2016-06-01

    Pollination success of animal-pollinated flowers depends on rate of pollinator visits and on pollen deposition per visit, both of which should vary with the pollen and nectar "neighborhoods" of a plant, i.e., with pollen and nectar availability in nearby plants. One determinant of these neighborhoods is per-flower production of pollen and nectar, which is likely to respond to environmental influences. In this study, we explored environmental effects on pollen and nectar production and on pollination success in order to follow up a surprising result from a previous study: flowers of Ipomopsis aggregata received less pollen in years of high visitation by their hummingbird pollinators. A new analysis of the earlier data indicated that high bird visitation corresponded to drought years. We hypothesized that drought might contribute to the enigmatic prior result if it decreases both nectar and pollen production: in dry years, low nectar availability could cause hummingbirds to visit flowers at a higher rate, and low pollen availability could cause them to deposit less pollen per visit. A greenhouse experiment demonstrated that drought does reduce both pollen and nectar production by I. aggregata flowers. This result was corroborated across 6 yr of variable precipitation and soil moisture in four unmanipulated field populations. In addition, experimental removal of pollen from flowers reduced the pollen received by nearby flowers. We conclude that there is much to learn about how abiotic and biotic environmental drivers jointly affect pollen and nectar production and availability, and how this contributes to pollen and nectar neighborhoods and thus influences pollination success.

  4. Novel design of honeybee-inspired needles for percutaneous procedure.

    Science.gov (United States)

    Sahlabadi, Mohammad; Hutapea, Parsaoran

    2018-04-18

    The focus of this paper is to present new designs of innovative bioinspired needles to be used during percutaneous procedures. Insect stingers have been known to easily penetrate soft tissues. Bioinspired needles mimicking the barbs in a honeybee stinger were developed for a smaller insertion force, which can provide a less invasive procedure. Decreasing the insertion force will decrease the tissue deformation, which is essential for more accurate targeting. In this study, some design parameters, in particular, barb shape and geometry (i.e. front angle, back angle, and height) were defined, and their effects on the insertion force were investigated. Three-dimensional printing technology was used to manufacture bioinspired needles. A specially-designed insertion test setup using tissue mimicking polyvinyl chloride (PVC) gels was developed to measure the insertion and extraction forces. The barb design parameters were then experimentally modified through detailed experimental procedures to further reduce the insertion force. Different scales of the barbed needles were designed and used to explore the size-scale effect on the insertion force. To further investigate the efficacy of the proposed needle design in real surgeries, preliminary ex vivo insertion tests into bovine liver tissue were performed. Our results show that the insertion force of the needles in different scales decreased by 21-35% in PVC gel insertion tests, and by 46% in bovine liver tissue insertion tests.

  5. Radioprotection: mechanism and radioprotective agents including honeybee venom

    Energy Technology Data Exchange (ETDEWEB)

    Varanda, E.A.; Tavares, D.C. [UNESP, Araraquara, SP (Brazil). Escola de Ciencias Farmaceuticas. Dept. de Ciencias Biologicas

    1998-07-01

    Since 1949, a great deal of research has been carried on the radioprotective action of chemical substances. These substances have shown to reduce mortality when administered to animals prior to exposure to a lethal dose of radiation. This fact is of considerable importance since it permits reduction of radiation-induced damage and provides prophylactic treatment for the damaging effects produced by radiotherapy. The following radioprotection mechanisms were proposed: free radical scavenger, repair by hydrogen donation to target molecules formation of mixed disulfides, delay of cellular division and induction of hypoxia in the tissues. Radioprotective agents have been divided into four major groups: the thiol compounds, other sulfur compounds, pharmacological agents (anesthetic drugs, analgesics, tranquilizers, etc.) and other radioprotective agents (WR-1065, WR-2721, vitamins C and E, glutathione, etc.). Several studies revealed the radioprotective action of Apis mellifera honeybee venom as well as that of its components mellitin and histamine. Radioprotective activity of bee venom involves mainly the stimulation of the hematopoietic system. In addition, release of histamine and reduction in oxygen tension also contribute to the radioprotective action of bee venom. (author)

  6. The connection between landscapes and the solar ephemeris in honeybees.

    Science.gov (United States)

    Towne, William F; Moscrip, Heather

    2008-12-01

    Honeybees connect the sun's daily pattern of azimuthal movement to some aspect of the landscape around their nests. In the present study, we ask what aspect of the landscape is used in this context--the entire landscape panorama or only sectors seen along familiar flight routes. Previous studies of the solar ephemeris memory in bees have generally used bees that had experience flying a specific route, usually along a treeline, to a feeder. When such bees were moved to a differently oriented treeline on overcast days, the bees oriented their communicative dances as if they were still at the first treeline, based on a memory of the sun's course in relation to some aspect of the site, possibly the familiar route along the treeline or possibly the entire landscape or skyline panorama. Our results show that bees lacking specific flight-route training can nonetheless recall the sun's compass bearing relative to novel flight routes in their natal landscape. Specifically, we moved a hive from one landscape to a differently oriented twin landscape, and only after transplantation under overcast skies did we move a feeder away from the hive. These bees nonetheless danced accurately by memory of the sun's course in relation to their natal landscape. The bees' knowledge of the relationship between the sun and landscape, therefore, is not limited to familiar flight routes and so may encompass, at least functionally, the entire panorama. Further evidence suggests that the skyline in particular may be the bees' preferred reference in this context.