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Sample records for extrafloral nectar efn

  1. Increased host investment in extrafloral nectar (EFN improves the efficiency of a mutualistic defensive service.

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    Marcia González-Teuber

    Full Text Available Extrafloral nectar (EFN plays an important role as plant indirect defence through the attraction of defending ants. Like all rewards produced in the context of a mutualism, however, EFN is in danger of being exploited by non-ant consumers that do not defend the plant against herbivores. Here we asked whether plants, by investing more in EFN, can improve their indirect defence, or rather increase the risk of losing this investment to EFN thieves. We used the obligate plant-ant Acacia-Pseudomyrmex system and examined experimentally in the field during the dry and the rainy seasons how variations in EFN secretion are related to (i ant activity, to (ii the ant-mediated defence against herbivores and (iii the exploitation of EFN by non-ant consumers. Extrafloral investment enhanced ant recruitment and was positively related to the ant mediated defence against herbivores. The ant-mediated protection from exploiters also increased in proportion to the nectar sugar concentration. Although the daily peak of EFN production coincided with the highest activity of EFN thieves, Pseudomyrmex ferrugineus ants protected this resource effectively from exploiters. Nevertheless, the defensive effects by ants differed among seasons. During the dry season, plants grew slower and secreted more EFN than in the rainy season, and thus, experienced a higher level of ant-mediated indirect defence. Our results show that an increased plant investment in an indirect defence trait can improve the resulting defensive service against both herbivores and exploiters. EFN secretion by obligate ant-plants represents a defensive trait for which the level of investment correlates positively with the beneficial effects obtained.

  2. Increased host investment in extrafloral nectar (EFN) improves the efficiency of a mutualistic defensive service.

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    González-Teuber, Marcia; Silva Bueno, Juan Carlos; Heil, Martin; Boland, Wilhelm

    2012-01-01

    Extrafloral nectar (EFN) plays an important role as plant indirect defence through the attraction of defending ants. Like all rewards produced in the context of a mutualism, however, EFN is in danger of being exploited by non-ant consumers that do not defend the plant against herbivores. Here we asked whether plants, by investing more in EFN, can improve their indirect defence, or rather increase the risk of losing this investment to EFN thieves. We used the obligate plant-ant Acacia-Pseudomyrmex system and examined experimentally in the field during the dry and the rainy seasons how variations in EFN secretion are related to (i) ant activity, to (ii) the ant-mediated defence against herbivores and (iii) the exploitation of EFN by non-ant consumers. Extrafloral investment enhanced ant recruitment and was positively related to the ant mediated defence against herbivores. The ant-mediated protection from exploiters also increased in proportion to the nectar sugar concentration. Although the daily peak of EFN production coincided with the highest activity of EFN thieves, Pseudomyrmex ferrugineus ants protected this resource effectively from exploiters. Nevertheless, the defensive effects by ants differed among seasons. During the dry season, plants grew slower and secreted more EFN than in the rainy season, and thus, experienced a higher level of ant-mediated indirect defence. Our results show that an increased plant investment in an indirect defence trait can improve the resulting defensive service against both herbivores and exploiters. EFN secretion by obligate ant-plants represents a defensive trait for which the level of investment correlates positively with the beneficial effects obtained.

  3. Increased Host Investment in Extrafloral Nectar (EFN) Improves the Efficiency of a Mutualistic Defensive Service

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    González-Teuber, Marcia; Silva Bueno, Juan Carlos; Heil, Martin; Boland, Wilhelm

    2012-01-01

    Extrafloral nectar (EFN) plays an important role as plant indirect defence through the attraction of defending ants. Like all rewards produced in the context of a mutualism, however, EFN is in danger of being exploited by non-ant consumers that do not defend the plant against herbivores. Here we asked whether plants, by investing more in EFN, can improve their indirect defence, or rather increase the risk of losing this investment to EFN thieves. We used the obligate plant-ant Acacia-Pseudomyrmex system and examined experimentally in the field during the dry and the rainy seasons how variations in EFN secretion are related to (i) ant activity, to (ii) the ant-mediated defence against herbivores and (iii) the exploitation of EFN by non-ant consumers. Extrafloral investment enhanced ant recruitment and was positively related to the ant mediated defence against herbivores. The ant-mediated protection from exploiters also increased in proportion to the nectar sugar concentration. Although the daily peak of EFN production coincided with the highest activity of EFN thieves, Pseudomyrmex ferrugineus ants protected this resource effectively from exploiters. Nevertheless, the defensive effects by ants differed among seasons. During the dry season, plants grew slower and secreted more EFN than in the rainy season, and thus, experienced a higher level of ant-mediated indirect defence. Our results show that an increased plant investment in an indirect defence trait can improve the resulting defensive service against both herbivores and exploiters. EFN secretion by obligate ant-plants represents a defensive trait for which the level of investment correlates positively with the beneficial effects obtained. PMID:23056362

  4. Extrafloral nectar fuels ant life in deserts.

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    Aranda-Rickert, Adriana; Diez, Patricia; Marazzi, Brigitte

    2014-11-07

    Interactions mediated by extrafloral nectary (EFN)-bearing plants that reward ants with a sweet liquid secretion are well documented in temperate and tropical habitats. However, their distribution and abundance in deserts are poorly known. In this study, we test the predictions that biotic interactions between EFN plants and ants are abundant and common also in arid communities and that EFNs are only functional when new vegetative and reproductive structures are developing. In a seasonal desert of northwestern Argentina, we surveyed the richness and phenology of EFN plants and their associated ants and examined the patterns in ant-plant interaction networks. We found that 25 ant species and 11 EFN-bearing plant species were linked together through 96 pairs of associations. Plants bearing EFNs were abundant, representing ca. 19 % of the species encountered in transects and 24 % of the plant cover. Most ant species sampled (ca. 77 %) fed on EF nectar. Interactions showed a marked seasonal pattern: EFN secretion was directly related to plant phenology and correlated with the time of highest ant ground activity. Our results reveal that EFN-mediated interactions are ecologically relevant components of deserts, and that EFN-bearing plants are crucial for the survival of desert ant communities. Published by Oxford University Press on behalf of the Annals of Botany Company.

  5. Pathogenesis-related proteins protect extrafloral nectar from microbial infestation.

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    González-Teuber, Marcia; Eilmus, Sascha; Muck, Alexander; Svatos, Ales; Heil, Martin

    2009-05-01

    Plants in more than 300 genera produce extrafloral nectar (EFN) to attract carnivores as a means of indirect defence against herbivores. As EFN is secreted at nectaries that are not physically protected from the environment, and contains carbohydrates and amino acids, EFN must be protected from infestation by micro-organisms. We investigated the proteins and anti-microbial activity in the EFN of two Central American Acacia myrmecophytes (A. cornigera and A. hindsii) and two related non-myrmecophytes (A. farnesiana and Prosopis juliflora). Acacia myrmecophytes secrete EFN constitutively at high rates to nourish the ants inhabiting these plants as symbiotic mutualists, while non-myrmecophytes secrete EFN only in response to herbivore damage to attract non-symbiotic ants. Thus, the quality and anti-microbial protection of the EFN secreted by these two types of plants were likely to differ. Indeed, myrmecophyte EFN contained significantly more proteins than the EFN of non-myrmecophytes, and was protected effectively from microbial infestation. We found activity for three classes of pathogenesis-related (PR) enzymes: chitinase, beta-1,3-glucanase and peroxidase. Chitinases and beta-1,3-glucanases were significantly more active in myrmecophyte EFN, and chitinase at the concentrations found in myrmecophyte EFN significantly inhibited yeast growth. Of the 52 proteins found in A. cornigera EFN, 28 were annotated using nanoLC-MS/MS data, indicating that chitinases and glucanases contribute more than 50% of the total protein content in the EFN of this myrmecophyte. Our study demonstrates that PR enzymes play an important role in protecting EFN from microbial infestation.

  6. Extrafloral nectar at the plant-insect interface: a spotlight on chemical ecology, phenotypic plasticity, and food webs.

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    Heil, Martin

    2015-01-07

    Plants secrete extrafloral nectar (EFN) as an induced defense against herbivores. EFN contains not only carbohydrates and amino acids but also pathogenesis-related proteins and other protective enzymes, making EFN an exclusive reward. EFN secretion is commonly induced after wounding, likely owing to a jasmonic acid-induced cell wall invertase, and is limited by phloem sucrose availability: Both factors control EFN secretion according to the optimal defense hypothesis. Non-ant EFN consumers include parasitoids, wasps, spiders, mites, bugs, and predatory beetles. Little is known about the relevance of EFN to the nutrition of its consumers and, hence, to the structuring of arthropod communities. The mutualism can be established quickly among noncoevolved (e.g., invasive) species, indicating its easy assembly is due to ecological fitting. Therefore, increasing efforts are directed toward using EFN in biocontrol. However, documentation of the importance of EFN for the communities of plants and arthropods in natural, invasive, and agricultural ecosystems is still limited.

  7. The role of extrafloral nectar amino acids for the preferences of facultative and obligate ant mutualists.

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    González-Teuber, Marcia; Heil, Martin

    2009-04-01

    Plants in some 300 genera produce extrafloral nectar (EFN) to attract ants as a means of indirect defence. Among Mesoamerican Acacia species, obligate myrmecophytes produce EFN constitutively to nourish symbiotic ant mutualists, while non-myrmecophytes induce EFN secretion in response to herbivore damage to attract non-symbiotic ants. Since symbiotic Acacia ants entirely depend on the host-derived food rewards while non-symbiotic ants need to be attracted to EFN, this system allows comparative analyses of the function of EFN components in ant nutrition and attraction. We investigated sugar and amino acid (AA) composition in EFN of two myrmecophytes (Acacia cornigera and Acacia hindsii) and two related non-myrmecophyte species (Acacia farnesiana and Prosopis juliflora). AA composition allowed a grouping of myrmecophytes vs. non-myrmecophytes. Behavioural assays with obligate Acacia inhabitants (Pseudomyrmex ferrugineus) and non-symbiotic ants showed that AA composition affected ant preferences at high but not at low AA/sugar ratios. Most interestingly, behavioural responses differed between the two types of ants tested: Symbiotic ants showed a clear preference for higher AA concentrations and preferred nectar mimics with those four AAs that most significantly characterised the specific nectar of their Acacia host plant. In contrast, non-symbiotic ants distinguished among nectars containing different sugars and between solutions with and without AAs but neither among nectars with different AA/sugar ratios nor among mimics containing different numbers of AAs. Our results confirm that both AAs and sugars contribute to the taste and attractiveness of nectars and demonstrate that the responses of ants to specific nectar components depend on their life style. AAs are a chemical EFN component that likely can shape the structure of ant-plant mutualisms.

  8. Extrafloral nectar content alters foraging preferences of a predatory ant.

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    Wilder, Shawn M; Eubanks, Micky D

    2010-04-23

    We tested whether the carbohydrate and amino acid content of extrafloral nectar affected prey choice by a predatory ant. Fire ants, Solenopsis invicta, were provided with artificial nectar that varied in the presence of carbohydrates and amino acids and were then provided with two prey items that differed in nutritional content, female and male crickets. Colonies of fire ants provided with carbohydrate supplements consumed less of the female crickets and frequently did not consume the high-lipid ovaries of female crickets. Colonies of fire ants provided with amino acid supplements consumed less of the male crickets. While a number of studies have shown that the presence of extrafloral nectar or honeydew can affect ant foraging activity, these results suggest that the nutritional composition of extrafloral nectar is also important and can affect subsequent prey choice by predatory ants. Our results suggest that, by altering the composition of extrafloral nectar, plants could manipulate the prey preferences of ants foraging on them.

  9. Glucanases and chitinases as causal agents in the protection of Acacia extrafloral nectar from infestation by phytopathogens.

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    González-Teuber, Marcia; Pozo, María J; Muck, Alexander; Svatos, Ales; Adame-Alvarez, Rosa M; Heil, Martin

    2010-03-01

    Nectars are rich in primary metabolites and attract mutualistic animals, which serve as pollinators or as an indirect defense against herbivores. Their chemical composition makes nectars prone to microbial infestation. As protective strategy, floral nectar of ornamental tobacco (Nicotiana langsdorffii x Nicotiana sanderae) contains "nectarins," proteins producing reactive oxygen species such as hydrogen peroxide. By contrast, pathogenesis-related (PR) proteins were detected in Acacia extrafloral nectar (EFN), which is secreted in the context of defensive ant-plant mutualisms. We investigated whether these PR proteins protect EFN from phytopathogens. Five sympatric species (Acacia cornigera, A. hindsii, A. collinsii, A. farnesiana, and Prosopis juliflora) were compared that differ in their ant-plant mutualism. EFN of myrmecophytes, which are obligate ant-plants that secrete EFN constitutively to nourish specialized ant inhabitants, significantly inhibited the growth of four out of six tested phytopathogenic microorganisms. By contrast, EFN of nonmyrmecophytes, which is secreted only transiently in response to herbivory, did not exhibit a detectable inhibitory activity. Combining two-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis with nanoflow liquid chromatography-tandem mass spectrometry analysis confirmed that PR proteins represented over 90% of all proteins in myrmecophyte EFN. The inhibition of microbial growth was exerted by the protein fraction, but not the small metabolites of this EFN, and disappeared when nectar was heated. In-gel assays demonstrated the activity of acidic and basic chitinases in all EFNs, whereas glucanases were detected only in EFN of myrmecophytes. Our results demonstrate that PR proteins causally underlie the protection of Acacia EFN from microorganisms and that acidic and basic glucanases likely represent the most important prerequisite in this defensive function.

  10. Phloem sugar flux and jasmonic acid-responsive cell wall invertase control extrafloral nectar secretion in Ricinus communis.

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    Millán-Cañongo, Cynthia; Orona-Tamayo, Domancar; Heil, Martin

    2014-07-01

    Plants secrete extrafloral nectar (EFN) that attracts predators. The efficiency of the resulting anti-herbivore defense depends on the quantity and spatial distribution of EFN. Thus, according to the optimal defense hypothesis (ODH), plants should secrete EFN on the most valuable organs and when herbivore pressure is high. Ricinus communis plants secreted most EFN on the youngest (i.e., most valuable) leaves and after the simulation of herbivory via the application of jasmonic acid (JA). Here, we investigated the physiological mechanisms that might produce these seemingly adaptive spatiotemporal patterns. Cell wall invertase (CWIN; EC 3.2.1.26) was most active in the hours before peak EFN secretion, its decrease preceded the decrease in EFN secretion, and CWIN activity was inducible by JA. Thus, CWIN appears to be a central player in EFN secretion: its activation by JA is likely to cause the induction of EFN secretion after herbivory. Shading individual leaves decreased EFN secretion locally on these leaves with no effect on CWIN activity in the nectaries, which is likely to be because it decreased the content of sucrose, the substrate of CWIN, in the phloem. Our results demonstrate how the interplay of two physiological processes can cause ecologically relevant spatiotemporal patterns in a plant defense trait.

  11. Density-mediated, context-dependent consumer-resource interactions between ants and extrafloral nectar plants.

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    Chamberlain, Scott A; Holland, J Nathaniel

    2008-05-01

    Interspecific interactions are often mediated by the interplay between resource supply and consumer density. The supply of a resource and a consumer's density response to it may in turn yield context-dependent use of other resources. Such consumer-resource interactions occur not only for predator-prey and competitive interactions, but for mutualistic ones as well. For example, consumer-resource interactions between ants and extrafloral nectar (EFN) plants are often mutualistic, as EFN resources attract and reward ants which protect plants from herbivory. Yet, ants also commonly exploit floral resources, leading to antagonistic consumer-resource interactions by disrupting pollination and plant reproduction. EFN resources associated with mutualistic ant-plant interactions may also mediate antagonistic ant-flower interactions through the aggregative density response of ants on plants, which could either exacerbate ant-flower interactions or alternatively satiate and distract ants from floral resources. In this study, we examined how EFN resources mediate the density response of ants on senita cacti in the Sonoran Desert and their context-dependent use of floral resources. Removal of EFN resources reduced the aggregative density of ants on plants, both on hourly and daily time scales. Yet, the increased aggregative ant density on plants with EFN resources decreased rather than increased ant use of floral resources, including contacts with and time spent in flowers. Behavioral assays showed no confounding effect of floral deterrents on ant-flower interactions. Thus, ant use of floral resources depends on the supply of EFN resources, which mediates the potential for both mutualistic and antagonistic interactions by increasing the aggregative density of ants protecting plants, while concurrently distracting ants from floral resources. Nevertheless, only certain years and populations of study showed an increase in plant reproduction through herbivore protection or ant

  12. Variation in Extrafloral Nectary Productivity Influences the Ant Foraging.

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    Lange, Denise; Calixto, Eduardo Soares; Del-Claro, Kleber

    2017-01-01

    Extrafloral nectar is the main food source offered by plants to predatory ants in most land environments. Although many studies have demonstrated the importance of extrafloral nectaries (EFNs) to plant defense against herbivores, the influence of EFNs secretory activity pattern on predatory ants remains yet not fully understood. Here, we verified the relation between the extrafloral nectar production of a plant community in Cerrado in different times of the day, and its attractiveness to ants. The extrafloral nectaries (EFNs) of seven plant species showed higher productivity overnight. Ant abundance was higher in times of large extrafloral nectar production, however, there was no positive relation between ant richness on plants and EFNs productivity. There was temporal resource partitioning among ant species, and it indicates strong resource competition. The nectar productivity varied among plant species and time of the day, and it influenced the visitation patterns of ants. Therefore, EFNs are a key ant-plant interaction driver in the studied system.

  13. Variation in Extrafloral Nectary Productivity Influences the Ant Foraging

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    2017-01-01

    Extrafloral nectar is the main food source offered by plants to predatory ants in most land environments. Although many studies have demonstrated the importance of extrafloral nectaries (EFNs) to plant defense against herbivores, the influence of EFNs secretory activity pattern on predatory ants remains yet not fully understood. Here, we verified the relation between the extrafloral nectar production of a plant community in Cerrado in different times of the day, and its attractiveness to ants. The extrafloral nectaries (EFNs) of seven plant species showed higher productivity overnight. Ant abundance was higher in times of large extrafloral nectar production, however, there was no positive relation between ant richness on plants and EFNs productivity. There was temporal resource partitioning among ant species, and it indicates strong resource competition. The nectar productivity varied among plant species and time of the day, and it influenced the visitation patterns of ants. Therefore, EFNs are a key ant-plant interaction driver in the studied system. PMID:28046069

  14. Ants are less attracted to the extrafloral nectar of plants with symbiotic, nitrogen-fixing rhizobia.

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    Godschalx, Adrienne L; Schädler, Martin; Trisel, Julie A; Balkan, Mehmet A; Ballhorn, Daniel J

    2015-02-01

    Plants simultaneously maintain mutualistic relationships with different partners that are connected through the same host, but do not interact directly. One or more participating mutualists may alter their host's phenotype, resulting in a shift in the host's ecological interactions with all other mutualists involved. Understanding the functional interplay of mutualists associated with the same host remains an important challenge in biology. Here, we show belowground nitrogen-fixing rhizobia on lima bean (Phaseolus lunatus) alter their host plant's defensive mutualism with aboveground ants. We induced extrafloral nectar (EFN), an indirect defense acting through ant attraction. We also measured various nutritive and defensive plant traits, biomass, and counted ants on rhizobial and rhizobia-free plants. Rhizobia increased plant protein as well as cyanogenesis, a direct chemical defense against herbivores, but decreased EFN. Ants were significantly more attracted to rhizobia-free plants, and our structural equation model shows a strong link between rhizobia and reduced EFN as well as between EFN and ants: the sole path to ant recruitment. The rhizobia-mediated effects on simultaneously expressed defensive plant traits indicate rhizobia can have significant bottom-up effects on higher trophic levels. Our results show belowground symbionts play a critical and underestimated role in determining aboveground mutualistic interactions.

  15. Comparison of Peach Cultivars for Provision of Extrafloral Nectar Resources to Harmonia axyridis (Coleoptera: Coccinellidae).

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    Mathews, Clarissa R; Brown, Mark W; Wäckers, Felix L

    2016-04-22

    Incorporating nonprey sugar resources into apple orchards is a potential means of enhancing biological control services, but little is known about the impacts of extrafloral nectars on aphidophagous coccinellids. We explored peach Prunus persica (L.) Batsch extrafloral nectar as a supplemental resource for Harmonia axyridis (Pallas), a key aphid predator in the mid-Atlantic United States. Extrafloral nectar quantity, temporal production, and carbohydrate profile were assessed for four peach cultivars in orchard and greenhouse culture. Seasonal densities of H. axyridis visiting extrafloral nectaries were estimated, and the propensity of beetles to feed upon extrafloral nectar was compared by cultivar in the laboratory. We also compared survival of newly eclosed adult pairs that were starved or fed aphids with or without extrafloral nectar. Peach extrafloral nectar contained six carbohydrates, with sucrose dominant for all cultivars, but extrafloral nectar production varied significantly by cultivar and collection date, with 'Lovell' yielding higher average seasonal volume than the other cultivars. Harmonia axyridis continuously foraged on peach trees lacking prey, and beetle abundance was positively correlated with the number of leaves actively producing extrafloral nectar. In laboratory assays, newly emerged adult beetles preferentially selected and consumed extrafloral nectar of Lovell peach shoots. Furthermore, when prey were initially unavailable to adult H. axyridis, the beetles were sustained by extrafloral nectar and experienced longer survival compared with beetles without the supplemental resource. Collectively, these results suggest that peach extrafloral nectar is a beneficial resource that could potentially sustain H. axyridis in orchards when prey are scarce. © 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.

  16. Feeding and survival of two nocturnal cursorial spiders on extrafloral nectar and honeydew sugars

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    Sugars in the form of extrafloral nectar and honeydews may be important resources for nocturnal cursorial spiders such as Cheiracanthium inclusum (Hentz) and Hibana futilis (Banks). C. inclusum spiderlings given only water survived an average of only 6.1 d. Feeding on cotton extrafloral nectar and m...

  17. Interaction Effect Between Herbivory and Plant Fertilization on Extrafloral Nectar Production and on Seed Traits: An Experimental Study With Ricinus communis (Euphorbiaceae).

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    De Sibio, P R; Rossi, M N

    2016-08-01

    It is known that the release of volatile chemicals by many plants can attract the natural enemies of herbivorous insects. Such indirect interactions are likely when plants produce nectar from their extrafloral nectaries, and particularly when the production of extrafloral nectar (EFN) is induced by herbivory. In the present study, we conducted experiments to test whether foliar herbivory inflicted by Spodoptera frugiperda Smith (Noctuidae) increases nectar production by extrafloral nectaries on one of its host plants, Ricinus communis L. (Euphorbiaceae). Due to the current economic importance of R. communis, we also investigated whether the following seed traits-water content, dry mass, and essential oil production-are negatively affected by herbivory. Finally, we tested whether or not nectar production and seed traits are influenced by plant fertilization (plant quality). We found that nectar production was increased after herbivory, but it was not affected by the type of fertilization. Seed dry mass was higher in plants that were subjected to full fertilization, without herbivory; plants maintained in low fertilization conditions, however, had higher seed mass when subjected to herbivory. The same inverted pattern was observed for oil production. Therefore, our results suggest that EFN production in R. communis may act as an indirect defense strategy against herbivores, and that there is a trade-off between reproduction and plant growth when low-fertilized plants are subjected to herbivory. © 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.

  18. Temporal Variation in the Abundance and Richness of Foliage-Dwelling Ants Mediated by Extrafloral Nectar

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    Belchior, Ceres; Sendoya, Sebastián F.

    2016-01-01

    Plants bearing extrafloral nectaries (EFNs) are common in the Brazilian cerrado savanna, where climatic conditions having marked seasonality influence arboreal ant fauna organization. These ant-plant interactions have rarely been studied at community level. Here, we tested whether: 1) EFN-bearing plants are more visited by ants than EFN-lacking plants; 2) ant visitation is higher in the rainy season than in dry season; 3) plants producing young leaves are more visited than those lacking young leaves in the rainy season; 4) during the dry season, plants with old leaves and flowers are more visited than plants with young leaves and bare of leaves or flowers; 5) the composition of visiting ant fauna differs between plants with and without EFNs. Field work was done in a cerrado reserve near Uberlândia, MG State, Brazil, along ten transects (total area 3,000 m2), in the rainy (October-January) and dry seasons (April-July) of 2010–2011. Plants (72 species; 762 individuals) were checked three times per season for ant presence. Results showed that 21 species (29%) and 266 individuals (35%) possessed EFNs. These plants attracted 38 ant species (36 in rainy, 26 in dry season). In the rainy season, plants with EFNs had higher ant abundance/richness than plants without EFNs, but in the dry season, EFN presence did not influence ant visitation. Plant phenology affected ant richness and abundance in different ways: plants with young leaves possessed higher ant richness in the rainy season, but in the dry season ant abundance was higher on plants possessing old leaves or flowers. The species composition of plant-associated ant communities, however, did not differ between plants with and without EFNs in either season. These findings suggest that the effect of EFN presence on a community of plant-visiting ants is context dependent, being conditioned to seasonal variation. PMID:27438722

  19. Temporal Variation in the Abundance and Richness of Foliage-Dwelling Ants Mediated by Extrafloral Nectar.

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    Ceres Belchior

    Full Text Available Plants bearing extrafloral nectaries (EFNs are common in the Brazilian cerrado savanna, where climatic conditions having marked seasonality influence arboreal ant fauna organization. These ant-plant interactions have rarely been studied at community level. Here, we tested whether: 1 EFN-bearing plants are more visited by ants than EFN-lacking plants; 2 ant visitation is higher in the rainy season than in dry season; 3 plants producing young leaves are more visited than those lacking young leaves in the rainy season; 4 during the dry season, plants with old leaves and flowers are more visited than plants with young leaves and bare of leaves or flowers; 5 the composition of visiting ant fauna differs between plants with and without EFNs. Field work was done in a cerrado reserve near Uberlândia, MG State, Brazil, along ten transects (total area 3,000 m2, in the rainy (October-January and dry seasons (April-July of 2010-2011. Plants (72 species; 762 individuals were checked three times per season for ant presence. Results showed that 21 species (29% and 266 individuals (35% possessed EFNs. These plants attracted 38 ant species (36 in rainy, 26 in dry season. In the rainy season, plants with EFNs had higher ant abundance/richness than plants without EFNs, but in the dry season, EFN presence did not influence ant visitation. Plant phenology affected ant richness and abundance in different ways: plants with young leaves possessed higher ant richness in the rainy season, but in the dry season ant abundance was higher on plants possessing old leaves or flowers. The species composition of plant-associated ant communities, however, did not differ between plants with and without EFNs in either season. These findings suggest that the effect of EFN presence on a community of plant-visiting ants is context dependent, being conditioned to seasonal variation.

  20. First observation of alternative food usage (extrafloral nectar by the assassin bug Atopozelus opsimus (Hemiptera, Reduviidae

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    Rhainer Guillermo-Ferreira

    2012-12-01

    Full Text Available Assassin bugs (Reduviidae are voracious insects that prey on other arthropods. Recent evidences have pointed out that these predators also feed on plant derived substances in rare opportunities. The present study describes the feeding behavior of the reduviid Atopozelus opsimus on extrafloral nectaries of Inga vera (Fabaceae in a Neotropical savanna area. It was investigated if the insects feed more frequently of extrafloral nectar or prey, and if individuals of different stages of development vary according to feeding behavior. Notably, the results suggest that the diet of all instars and adults consist mainly of extrafloral nectar (N = 1013, in detriment of captured prey ingestion (N = 18. Also, there was no variation on feeding behavior and life stage.

  1. Extrafloral nectar feeding by Strymon jacqueline Nicolay & Robbins, 2005 (Lepidoptera: Lycaenidae: Eumaeini

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    Roger Vila

    2006-10-01

    Full Text Available Adults of the dry area specialist Strymon jacqueline Nicolay & Robbins, 2005 (Lepidoptera: Lycaenidae: Eumaeini are here recorded feeding on extrafloral nectar of the large cactus Neoraimondia arequipensis var. gigantea (Werdermann & Backeberg Ritter. The significance of these observations is discussed in relation to lycaenid survival in a xeric environment, pollination and mate location.

  2. Extrafloral-nectar-based partner manipulation in plant–ant relationships

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    Grasso, D. A.; Pandolfi, C.; Bazihizina, N.; Nocentini, D.; Nepi, M.; Mancuso, S.

    2015-01-01

    Plant–ant interactions are generally considered as mutualisms, with both parties gaining benefits from the association. It has recently emerged that some of these mutualistic associations have, however, evolved towards other forms of relationships and, in particular, that plants may manipulate their partner ants to make reciprocation more beneficial, thereby stabilizing the mutualism. Focusing on plants bearing extrafloral nectaries, we review recent studies and address three key questions: (i) how can plants attract potential partners and maintain their services; (ii) are there compounds in extrafloral nectar that could mediate partner manipulation; and (iii) are ants susceptible to such compounds? After reviewing the current knowledge on plant–ant associations, we propose a possible scenario where plant-derived chemicals, such as secondary metabolites, known to have an impact on animal brain, could have evolved in plants to attract and manipulate ant behaviour. This new viewpoint would place plant–animal interaction in a different ecological context, opening new ecological and neurobiological perspectives of drug seeking and use. PMID:25589521

  3. Extrafloral-nectar-based partner manipulation in plant-ant relationships.

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    Grasso, D A; Pandolfi, C; Bazihizina, N; Nocentini, D; Nepi, M; Mancuso, S

    2015-01-14

    Plant-ant interactions are generally considered as mutualisms, with both parties gaining benefits from the association. It has recently emerged that some of these mutualistic associations have, however, evolved towards other forms of relationships and, in particular, that plants may manipulate their partner ants to make reciprocation more beneficial, thereby stabilizing the mutualism. Focusing on plants bearing extrafloral nectaries, we review recent studies and address three key questions: (i) how can plants attract potential partners and maintain their services; (ii) are there compounds in extrafloral nectar that could mediate partner manipulation; and (iii) are ants susceptible to such compounds? After reviewing the current knowledge on plant-ant associations, we propose a possible scenario where plant-derived chemicals, such as secondary metabolites, known to have an impact on animal brain, could have evolved in plants to attract and manipulate ant behaviour. This new viewpoint would place plant-animal interaction in a different ecological context, opening new ecological and neurobiological perspectives of drug seeking and use. Published by Oxford University Press on behalf of the Annals of Botany Company.

  4. Extrafloral nectaries in Combretaceae: morphology, anatomy and taxonomic significance

    Directory of Open Access Journals (Sweden)

    P. M. Tilney

    2004-12-01

    Full Text Available Extrafloral nectaries (EFNs in members of the Combretaceae are nectaries not involved with pollination and occurring on vegetative structures; they are believed to attract ants to protect plants against herbivorv by other insects. In the Combretaceae EFNs are reported in species of Terminalia L. and Pteleopsis Engl., putative EFNs in Meiostemon Exell & Stace and Quisqualis L., and an absence of EFNs in Combretum Loefl. and Lumnitzera Willd. EFNs in the family are generally spherical in shape and may be raised, level with the surface or somewhat concave. They are similar in the Terminalia and  Pteleopsis species where they display varying degrees of internal zonation and are composed of small cells; those species observed in the field were all found to have functional EFNs. In Meiostemon tetrandrum (Exell Exell & Stace, Quisqualis indica L.. Q. littorea (Engl. Exell and Q. paviflora Gerrard ex Sond.. apparent EFNs lack internal zonation and are composed of enlarged cells; confirmation is required as to whether these are functional . The formation of EFNs appears to be highly flexible. They are usually essentially associated with new growth but their occurrence is sporadic and they do not appear on every leaf or every' branch of a plant. The distribution of EFNs on leaves, when present, is of taxonomic significance to separate species of Pteleopsis and Terminalia: otherwise the presence or absence and distribution of EFNs are too variable and sporadic in occurrence to be of taxonomic significance at the species level. Indiscriminate use of the terms gland and domatium instead of EFN. and possible confusion with damage caused by other organisms, has probably con­tributed to many of these structures not previously being recorded as EFNs. Floral and extrafloral nectar samples of T. phanerophlebia Engl. & Diels differed in sugar composition.

  5. Postsecretory hydrolysis of nectar sucrose and specialization in ant/plant mutualism.

    Science.gov (United States)

    Heil, M; Rattke, J; Boland, W

    2005-04-22

    Obligate Acacia ant plants house mutualistic ants as a defense mechanism and provide them with extrafloral nectar (EFN). Ant/plant mutualisms are widespread, but little is known about the biochemical basis of their species specificity. Despite its importance in these and other plant/animal interactions, little attention has been paid to the control of the chemical composition of nectar. We found high invertase (sucrose-cleaving) activity in Acacia EFN, which thus contained no sucrose. Sucrose, a disaccharide common in other EFNs, usually attracts nonsymbiotic ants. The EFN of the ant acacias was therefore unattractive to such ants. The Pseudomyrmex ants that are specialized to live on Acacia had almost no invertase activity in their digestive tracts and preferred sucrose-free EFN. Our results demonstrate postsecretory regulation of the carbohydrate composition of nectar.

  6. Effect of post-fire resprouting on leaf fluctuating asymmetry, extrafloral nectar quality, and ant-plant-herbivore interactions

    Science.gov (United States)

    Alves-Silva, Estevão; Del-Claro, Kleber

    2013-06-01

    Fires in the Cerrado savanna are a severe form of disturbance, but some species are capable of resprouting afterwards. It is unknown, however, how and whether post-fire resprouting represents a stressful condition to plants and how their rapid re-growth influences both the production of biochemical compounds, and interactions with mutualistic ants. In this study, we examined the influence of post-fire resprouting on biotic interactions (ant-plant-herbivore relationships) and on plant stress. The study was performed on two groups of the extrafloral nectaried shrub Banisteriopsis campestris (Malpighiaceae); one group was recovering from fire while the other acted as control. With respect to biotic interactions, we examined whether resprouting influenced extrafloral nectar concentration (milligrams per microliter), the abundance of the ant Camponotus crassus and leaf herbivory rates. Plant stress was assessed via fluctuating asymmetry (FA) analysis, which refers to deviations from perfect symmetry in bilaterally symmetrical traits (e.g., leaves) and indicates whether species are under stress. Results revealed that FA, sugar concentration, and ant abundance were 51.7 %, 35.7 % and 21.7 % higher in resprouting plants. Furthermore, C. crassus was significantly associated with low herbivory rates, but only in resprouting plants. This study showed that post-fire resprouting induced high levels of plant stress and influenced extrafloral nectar quality and ant-herbivore relationships in B. campestris. Therefore, despite being a stressful condition to the plant, post-fire resprouting individuals had concentrated extrafloral nectar and sustained more ants, thus strengthening the outcomes of ant-plant mutualism.

  7. The diversity, ecology and evolution of extrafloral nectaries: current perspectives and future challenges.

    Science.gov (United States)

    Marazzi, Brigitte; Bronstein, Judith L; Koptur, Suzanne

    2013-06-01

    Plants in over one hundred families in habitats worldwide bear extrafloral nectaries (EFNs). EFNs display a remarkable diversity of evolutionary origins, as well as diverse morphology and location on the plant. They secrete extrafloral nectar, a carbohydrate-rich food that attracts ants and other arthropods, many of which protect the plant in return. By fostering ecologically important protective mutualisms, EFNs play a significant role in structuring both plant and animal communities. And yet researchers are only now beginning to appreciate their importance and the range of ecological, evolutionary and morphological diversity that EFNs exhibit. This Highlight features a series of papers that illustrate some of the newest directions in the study of EFNs. Here, we introduce this set of papers by providing an overview of current understanding and new insights on EFN diversity, ecology and evolution. We highlight major gaps in our current knowledge, and outline future research directions. Our understanding of the roles EFNs play in plant biology is being revolutionized with the use of new tools from developmental biology and genomics, new modes of analysis allowing hypothesis-testing in large-scale phylogenetic frameworks, and new levels of inquiry extending to community-scale interaction networks. But many central questions remain unanswered; indeed, many have not yet been asked. Thus, the EFN puzzle remains an intriguing challenge for the future.

  8. Large-scale patterns of diversification in the widespread legume genus Senna and the evolutionary role of extrafloral nectaries.

    Science.gov (United States)

    Marazzi, Brigitte; Sanderson, Michael J

    2010-12-01

    Unraveling the diversification history of old, species-rich and widespread clades is difficult because of extinction, undersampling, and taxonomic uncertainty. In the context of these challenges, we investigated the timing and mode of lineage diversification in Senna (Leguminosae) to gain insights into the evolutionary role of extrafloral nectaries (EFNs). EFNs secrete nectar, attracting ants and forming ecologically important ant-plant mutualisms. In Senna, EFNs characterize one large clade (EFN clade), including 80% of its 350 species. Taxonomic accounts make Senna the largest caesalpinioid genus, but quantitative comparisons to other taxa require inferences about rates. Molecular dating analyses suggest that Senna originated in the early Eocene, and its major lineages appeared during early/mid Eocene to early Oligocene. EFNs evolved in the late Eocene, after the main radiation of ants. The EFN clade diversified faster, becoming significantly more species-rich than non-EFN clades. The shift in diversification rates associated with EFN evolution supports the hypothesis that EFNs represent a (relatively old) key innovation in Senna. EFNs may have promoted the colonization of new habitats appearing with the early uplift of the Andes. This would explain the distinctive geographic concentration of the EFN clade in South America. © 2010 The Author(s). Evolution© 2010 The Society for the Study of Evolution.

  9. Review: Nectar biology: From molecules to ecosystems.

    Science.gov (United States)

    Roy, Rahul; Schmitt, Anthony J; Thomas, Jason B; Carter, Clay J

    2017-09-01

    Plants attract mutualistic animals by offering a reward of nectar. Specifically, floral nectar (FN) is produced to attract pollinators, whereas extrafloral nectar (EFN) mediates indirect defenses through the attraction of mutualist predatory insects to limit herbivory. Nearly 90% of all plant species, including 75% of domesticated crops, benefit from animal-mediated pollination, which is largely facilitated by FN. Moreover, EFN represents one of the few defense mechanisms for which stable effects on plant health and fitness have been demonstrated in multiple systems, and thus plays a crucial role in the resistance phenotype of plants producing it. In spite of its central role in plant-animal interactions, the molecular events involved in the development of both floral and extrafloral nectaries (the glands that produce nectar), as well as the synthesis and secretion of the nectar itself, have been poorly understood until recently. This review will cover major recent developments in the understanding of (1) nectar chemistry and its role in plant-mutualist interactions, (2) the structure and development of nectaries, (3) nectar production, and (4) its regulation by phytohormones. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Do extrafloral nectar resources, species abundances, and body sizes contribute to the structure of ant-plant mutualistic networks?

    Science.gov (United States)

    Chamberlain, Scott A; Kilpatrick, Jeffrey R; Holland, J Nathaniel

    2010-11-01

    Recent research has shown that many mutualistic communities display non-random structures. While our understanding of the structural properties of mutualistic communities continues to improve, we know little of the biological variables resulting in them. Mutualistic communities include those formed between ants and extrafloral (EF) nectar-bearing plants. In this study, we examined the contributions of plant and ant abundance, plant and ant size, and plant EF nectar resources to the network structures of nestedness and interaction frequency of ant-plant networks across five sites within one geographic locality in the Sonoran Desert. Interactions between ant and plant species were largely symmetric. That is, ant and plant species exerted nearly equivalent quantitative interaction effects on one another, as measured by their frequency of interaction. The mutualistic ant-plant networks also showed nested patterns of structure, in which there was a central core of generalist ant and plant species interacting with one another and few specialist-specialist interactions. Abundance and plant size and ant body size were the best predictors of symmetric interactions between plants and ants, as well as nestedness. Despite interactions in these communities being ultimately mediated by EF nectar resources, the number of EF nectaries had a relatively weak ability to explain variation in symmetric interactions and nestedness. These results suggest that different mechanisms may contribute to structure of bipartite networks. Moreover, our results for ant-plant mutualistic networks support the general importance of species abundances for the structure of species interactions within biological communities.

  11. Diversity and distribution of extra-floral nectaries in the cerrado savanna vegetation of Brazil.

    Science.gov (United States)

    Boudouris, John; Queenborough, Simon A

    2013-01-01

    Aim. Throughout evolutionary history, plants and animals have evolved alongside one another. This is especially apparent when considering mutualistic relationships such as between plants with extra-floral nectaries (EFNs, glands on leaves or stems that secrete nectar) and the ants that visit them. Ants are attracted by the nectar and then protect the plant against destructive herbivores. The distribution of these plants is of particular interest, because it can provide insights into the evolutionary history of this unique trait and the plants that possess it. In this study, we investigated factors driving the distribution of woody plants with EFNs in the cerrado vegetation of Brazil. Location. Brazil Methods. We used a database detailing the incidence of 849 plant species at 367 cerrado sites throughout Brazil. We determined which species possessed EFNs and mapped their distributions. We tested for correlations between the proportion of EFN species at each site and (i) three environmental variables (mean annual temperature, mean annual precipitation, and the precipitation in the driest quarter of the year), (ii) a broad soil classification, and (iii) the total species diversity of each site. Results. We found a wide range in the proportion of EFN species at any one site (0-57%). However, whilst low diversity sites had wide variation in the number of EFN species, high diversity sites all had few EFN species. The proportion of EFN species was positively correlated with absolute latitude and negatively correlated with longitude. When accounting for total species diversity, the proportion of EFN species per site was negatively correlated with precipitation in the driest quarter of the year and positively correlated with temperature range. Main Conclusions. These results suggest either that herbivore pressure may be lower in drier sites, or that ants are not as dominant in these locations, or that plant lineages at these sites were unable to evolve EFNs.

  12. Occurrence and structure of extrafloral nectariesin Pterodon pubescens Benth. and Pterodon polygalaeflorus Benth.

    Directory of Open Access Journals (Sweden)

    Paiva Élder Antônio Sousa e

    2001-01-01

    Full Text Available Extrafloral nectaries (EFNs are structurally variable and widely spread among the angiosperms. The occurrence of EFNs in leaves of Pterodon polygalaeflorus Benth. and Pterodon pubescens Benth. (Fabaceae: Papilionoideae were detected in adult specimens, at the time of production of new buds and flowers. The goals of the present study are to register the occurrence of the EFNs in P. pubescens and P. polygalaeflorus, and provide comparative data on the anatomical structures. The EFNs occur in the rachis and are located under the insertion of each petiolule. Each nectary consists of a small elevation whose apical portion is deeply invaginated, resulting in a depression (secretory pole, a common characteristic of both species. Unicellular, nonglandular trichomes occur along the rachis, being less numerous in P. polygalaeflorus while in P. pubescens they cover the EFNs. The secretory tissue consists of parenchyma cells with dense cytoplasm compactly arranged. The nectar reaches the surface of the EFNs by rupturing the thin cuticle which covers the secretory pole, since both species lack stomata or any other interruption at the epidermis. The basic difference between the two species, in relation to the EFNs, is the density of the pubescence, which is always greater in P. pubescens. Structural and dimensional modifications may be observed, even between basal and apical nectaries in the same rachis, so it does not constitute a taxonomical tool.

  13. Physiological benefits of nectar-feeding by a predatory beetle

    Science.gov (United States)

    Extrafloral nectar is an important food source for many animals, including predatory lady beetles (Coleoptera: Coccinellidae), although the physiological benefits of nectar consumption are poorly understood for most consumers. Under laboratory conditions, we confined new females of Coleomegilla macu...

  14. Non-additive benefit or cost? Disentangling the indirect effects that occur when plants bearing extrafloral nectaries and honeydew-producing insects share exotic ant mutualists

    Science.gov (United States)

    Savage, Amy M.; Rudgers, Jennifer A.

    2013-01-01

    Background and Aims In complex communities, organisms often form mutualisms with multiple different partners simultaneously. Non-additive effects may emerge among species linked by these positive interactions. Ants commonly participate in mutualisms with both honeydew-producing insects (HPI) and their extrafloral nectary (EFN)-bearing host plants. Consequently, HPI and EFN-bearing plants may experience non-additive benefits or costs when these groups co-occur. The outcomes of these interactions are likely to be influenced by variation in preferences among ants for honeydew vs. nectar. In this study, a test was made for non-additive effects on HPI and EFN-bearing plants resulting from sharing exotic ant guards. Preferences of the dominant exotic ant species for nectar vs. honeydew resources were also examined. Methods Ant access, HPI and nectar availability were manipulated on the EFN-bearing shrub, Morinda citrifolia, and ant and HPI abundances, herbivory and plant growth were assessed. Ant-tending behaviours toward HPI across an experimental gradient of nectar availability were also tracked in order to investigate mechanisms underlying ant responses. Key Results The dominant ant species, Anoplolepis gracilipes, differed from less invasive ants in response to multiple mutualists, with reductions in plot-wide abundances when nectar was reduced, but no response to HPI reduction. Conversely, at sites where A. gracilipes was absent or rare, abundances of less invasive ants increased when nectar was reduced, but declined when HPI were reduced. Non-additive benefits were found at sites dominated by A. gracilipes, but only for M. citrifolia plants. Responses of HPI at these sites supported predictions of the non-additive cost model. Interestingly, the opposite non-additive patterns emerged at sites dominated by other ants. Conclusions It was demonstrated that strong non-additive benefits and costs can both occur when a plant and herbivore share mutualist partners. These

  15. Interactions between extrafloral nectaries, aphids and ants: are there competition effects between plant and homopteran sugar sources?

    NARCIS (Netherlands)

    Engel, V.; Fischer, M.D.; Wäckers, F.L.; Volkl, W.

    2001-01-01

    Broad bean (Vicia faba), an annual plant bearing extrafloral nectaries (EFN) at the base of the upper leaves, is regularly infested by two aphid species, Aphis fabae and Acyrthosiphon pisum. EFN and A. fabae are commonly attended by the ant, Lasius niger, while Ac. pisum usually remains uninfested.

  16. EFNS task force

    DEFF Research Database (Denmark)

    Filippi, M; Agosta, F; Barkhof, F;

    2012-01-01

    The European Federation of the Neurological Societies (EFNS) guidelines on the use of neuroimaging in the diagnosis and management of dementia are designed to revise and expand previous EFNS recommendations for the diagnosis and management of patients with Alzheimer's disease (AD) and to provide ...... an overview of the evidence for the use of neuroimaging techniques in non-AD dementias, as well as general recommendations that apply to all types of dementia in clinical practice....

  17. The Influence of Host Plant Extrafloral Nectaries on Multitrophic Interactions: An Experimental Investigation.

    Science.gov (United States)

    Koptur, Suzanne; Jones, Ian M; Peña, Jorge E

    2015-01-01

    A field experiment was conducted with outplantings of the native perennial shrub Senna mexicana var. chapmanii in a semi-natural area adjacent to native pine rockland habitat in southern Florida. The presence of ants and the availability of extrafloral nectar were manipulated in a stratified random design. Insect communities were monitored and recorded over a period of six months with a view to addressing three main questions. Do ants provide biotic defense against key herbivores on S. chapmanii? Is the presence of ants on S. chapmanii mediated by EFN? Finally, are there ecological costs associated with the presence of ants on S. chapmanii, such as a reduction in alternative predator or parasitoid numbers? Herbivores on S. chapmanii included immature stages of three pierid butterflies, and adult weevils. Eight species of ants were associated with the plants, and other predators included spiders, ladybugs, wasps, and hemipterans. Parasitic, haemolymph-sucking midges (Ceratopogonidae) and parasitoid flies were also associated with the caterpillar herbivores, and possibly the extrafloral nectaries of the plants. The presence of ants did not appear to influence oviposition by butterflies, as numbers of lepidopterans of all developmental stages did not differ among treatments. Significantly more late instar caterpillars, however, were observed on plants with ants excluded, indicating that ants remove small caterpillars from plants. Substantially more alternative predators (spiders, ladybugs, and wasps) were observed on plants with ants excluded. Rates of parasitization did not differ among the treatments, but there were substantially fewer caterpillars succumbing to virus among those collected from control plants. We provide a rare look at facultative ant-plant mutualisms in the context of the many other interactions with which they overlap. We conclude that ants provide some biotic defense against herbivores on S. chapmanii, and plants benefit overall from the presence

  18. The Influence of Host Plant Extrafloral Nectaries on Multitrophic Interactions: An Experimental Investigation.

    Directory of Open Access Journals (Sweden)

    Suzanne Koptur

    Full Text Available A field experiment was conducted with outplantings of the native perennial shrub Senna mexicana var. chapmanii in a semi-natural area adjacent to native pine rockland habitat in southern Florida. The presence of ants and the availability of extrafloral nectar were manipulated in a stratified random design. Insect communities were monitored and recorded over a period of six months with a view to addressing three main questions. Do ants provide biotic defense against key herbivores on S. chapmanii? Is the presence of ants on S. chapmanii mediated by EFN? Finally, are there ecological costs associated with the presence of ants on S. chapmanii, such as a reduction in alternative predator or parasitoid numbers? Herbivores on S. chapmanii included immature stages of three pierid butterflies, and adult weevils. Eight species of ants were associated with the plants, and other predators included spiders, ladybugs, wasps, and hemipterans. Parasitic, haemolymph-sucking midges (Ceratopogonidae and parasitoid flies were also associated with the caterpillar herbivores, and possibly the extrafloral nectaries of the plants. The presence of ants did not appear to influence oviposition by butterflies, as numbers of lepidopterans of all developmental stages did not differ among treatments. Significantly more late instar caterpillars, however, were observed on plants with ants excluded, indicating that ants remove small caterpillars from plants. Substantially more alternative predators (spiders, ladybugs, and wasps were observed on plants with ants excluded. Rates of parasitization did not differ among the treatments, but there were substantially fewer caterpillars succumbing to virus among those collected from control plants. We provide a rare look at facultative ant-plant mutualisms in the context of the many other interactions with which they overlap. We conclude that ants provide some biotic defense against herbivores on S. chapmanii, and plants benefit overall

  19. The Influence of Host Plant Extrafloral Nectaries on Multitrophic Interactions: An Experimental Investigation

    Science.gov (United States)

    Koptur, Suzanne; Jones, Ian M.; Peña, Jorge E.

    2015-01-01

    A field experiment was conducted with outplantings of the native perennial shrub Senna mexicana var. chapmanii in a semi-natural area adjacent to native pine rockland habitat in southern Florida. The presence of ants and the availability of extrafloral nectar were manipulated in a stratified random design. Insect communities were monitored and recorded over a period of six months with a view to addressing three main questions. Do ants provide biotic defense against key herbivores on S. chapmanii? Is the presence of ants on S. chapmanii mediated by EFN? Finally, are there ecological costs associated with the presence of ants on S. chapmanii, such as a reduction in alternative predator or parasitoid numbers? Herbivores on S. chapmanii included immature stages of three pierid butterflies, and adult weevils. Eight species of ants were associated with the plants, and other predators included spiders, ladybugs, wasps, and hemipterans. Parasitic, haemolymph-sucking midges (Ceratopogonidae) and parasitoid flies were also associated with the caterpillar herbivores, and possibly the extrafloral nectaries of the plants. The presence of ants did not appear to influence oviposition by butterflies, as numbers of lepidopterans of all developmental stages did not differ among treatments. Significantly more late instar caterpillars, however, were observed on plants with ants excluded, indicating that ants remove small caterpillars from plants. Substantially more alternative predators (spiders, ladybugs, and wasps) were observed on plants with ants excluded. Rates of parasitization did not differ among the treatments, but there were substantially fewer caterpillars succumbing to virus among those collected from control plants. We provide a rare look at facultative ant-plant mutualisms in the context of the many other interactions with which they overlap. We conclude that ants provide some biotic defense against herbivores on S. chapmanii, and plants benefit overall from the presence

  20. The effect of herbivory on temporal and spatial dynamics of foliar nectar production in cotton and castor

    NARCIS (Netherlands)

    Wäckers, F.L.; Zuber, D.; Wunderlin, R.; Keller, F.

    2001-01-01

    The effects of feeding Spodoptera littoralis(Boisd.) (Lepidoptera: Noctuidae) larvae on the quantity and distribution of extrafloral nectar production by leaves of castor (Ricinus communis) and cotton (Gossypium herbaceum) were investigated. Following larval feeding, the total volume of nectar

  1. The effect of herbivory on temporal and spatial dynamics of foliar nectar production in cotton and castor

    NARCIS (Netherlands)

    Wäckers, F.L.; Zuber, D.; Wunderlin, R.; Keller, F.

    2001-01-01

    The effects of feeding Spodoptera a littoralis (Boisd.) (Lepidoptera: Noctuidae) larvae on the quantity and distribution of extrafloral nectar production by leaves of castor ((Ricinus communis) and cotton (Gossypium herbaceum) were investigated. Following larval feeding, the total volume of nectar

  2. Defensive effects of extrafloral nectaries in quaking aspen differ with scale.

    Science.gov (United States)

    Mortensen, Brent; Wagner, Diane; Doak, Patricia

    2011-04-01

    The effects of plant defenses on herbivory can differ among spatial scales. This may be particularly common with indirect defenses, such as extrafloral nectaries (EFNs), that attract predatory arthropods and are dependent on predator distribution, abundance, and behavior. We tested the defensive effects of EFNs in quaking aspen (Populus tremuloides Michx.) against damage by a specialist herbivore, the aspen leaf miner (Phyllocnistis populiella Cham.), at the scale of individual leaves and entire ramets (i.e., stems). Experiments excluding crawling arthropods revealed that the effects of aspen EFNs differed at the leaf and ramet scales. Crawling predators caused similar reductions in the percent leaf area mined on individual leaves with and without EFNs. However, the extent to which crawling predators increased leaf miner mortality and, consequently, reduced mining damage increased with EFN expression at the ramet scale. Thus, aspen EFNs provided a diffuse defense, reducing damage to leaves across a ramet regardless of leaf-scale EFN expression. We detected lower leaf miner damage and survival unassociated with crawling predators on EFN-bearing leaves, suggesting that direct defenses (e.g., chemical defenses) were stronger on leaves with than without EFNs. Greater direct defenses on EFN-bearing leaves may reduce the probability of losing these leaves and thus weakening ramet-scale EFN defense. Aspen growth was not related to EFN expression or the presence of crawling predators over the course of a single season. Different effects of aspen EFNs at the leaf and ramet scales suggest that future studies may benefit from examining indirect defenses simultaneously at multiple scales.

  3. Ant foraging on extrafloral nectaries of Qualea grandiflora (Vochysiaceae) in cerrado vegetation: ants as potential antiherbivore agents.

    Science.gov (United States)

    Oliveira, P S; da Silva, A F; Martins, A B

    1987-12-01

    Qualea grandiflora is a typical tree of Brazilian cerrados (savanna-like vegetation) that bears paired extrafloral nectaries (EFNs) along its stems. Results show that possession of EFNs increases ant density on Q. grandiflora shrubs over that of neighbouring non-nectariferous plants. Frequency of ant occupancy and mean number of ants per plant were much higher on Qualea than on plants lacking EFNs. These differences resulted in many more live termitebaits being attacked by foraging ants on Qualea than on neighbours without EFNs. Termites were attacked in equal numbers and with equal speeds on different-aged leaves of Qualea. The greatest potential for herbivore deterrence was presented by Camponotus ants (C. crassus, C. rufipes and C. aff. blandus), which together attacked significantly more termites than nine other ant species grouped. EFNs are regarded as important promoters of ant activity on cerado plants.

  4. How to be sweet? Extra floral nectar allocation by Gossypium hirsutum fits optimal defense theory predictions

    NARCIS (Netherlands)

    Wäckers, F.L.; Bonifay, C.

    2004-01-01

    Plants employ nectar for two distinct functions. Floral nectar has traditionally been viewed in the context of pollination. Extrafloral nectar on the other hand, can act as an indirect defense, allowing the plant to recruit predators and parasitoids. Whereas this makes for a clear-cut categorization

  5. Geographic Mosaic of Plant Evolution: Extrafloral Nectary Variation Mediated by Ant and Herbivore Assemblages

    Science.gov (United States)

    Nogueira, Anselmo; Rey, Pedro J.; Alcántara, Julio M.; Feitosa, Rodrigo M.; Lohmann, Lúcia G.

    2015-01-01

    Herbivory is an ecological process that is known to generate different patterns of selection on defensive plant traits across populations. Studies on this topic could greatly benefit from the general framework of the Geographic Mosaic Theory of Coevolution (GMT). Here, we hypothesize that herbivory represents a strong pressure for extrafloral nectary (EFN) bearing plants, with differences in herbivore and ant visitor assemblages leading to different evolutionary pressures among localities and ultimately to differences in EFN abundance and function. In this study, we investigate this hypothesis by analyzing 10 populations of Anemopaegma album (30 individuals per population) distributed through ca. 600 km of Neotropical savanna and covering most of the geographic range of this plant species. A common garden experiment revealed a phenotypic differentiation in EFN abundance, in which field and experimental plants showed a similar pattern of EFN variation among populations. We also did not find significant correlations between EFN traits and ant abundance, herbivory and plant performance across localities. Instead, a more complex pattern of ant–EFN variation, a geographic mosaic, emerged throughout the geographical range of A. album. We modeled the functional relationship between EFNs and ant traits across ant species and extended this phenotypic interface to characterize local situations of phenotypic matching and mismatching at the population level. Two distinct types of phenotypic matching emerged throughout populations: (1) a population with smaller ants (Crematogaster crinosa) matched with low abundance of EFNs; and (2) seven populations with bigger ants (Camponotus species) matched with higher EFN abundances. Three matched populations showed the highest plant performance and narrower variance of EFN abundance, representing potential plant evolutionary hotspots. Cases of mismatched and matched populations with the lowest performance were associated with abundant

  6. Geographic mosaic of plant evolution: extrafloral nectary variation mediated by ant and herbivore assemblages.

    Directory of Open Access Journals (Sweden)

    Anselmo Nogueira

    Full Text Available Herbivory is an ecological process that is known to generate different patterns of selection on defensive plant traits across populations. Studies on this topic could greatly benefit from the general framework of the Geographic Mosaic Theory of Coevolution (GMT. Here, we hypothesize that herbivory represents a strong pressure for extrafloral nectary (EFN bearing plants, with differences in herbivore and ant visitor assemblages leading to different evolutionary pressures among localities and ultimately to differences in EFN abundance and function. In this study, we investigate this hypothesis by analyzing 10 populations of Anemopaegma album (30 individuals per population distributed through ca. 600 km of Neotropical savanna and covering most of the geographic range of this plant species. A common garden experiment revealed a phenotypic differentiation in EFN abundance, in which field and experimental plants showed a similar pattern of EFN variation among populations. We also did not find significant correlations between EFN traits and ant abundance, herbivory and plant performance across localities. Instead, a more complex pattern of ant-EFN variation, a geographic mosaic, emerged throughout the geographical range of A. album. We modeled the functional relationship between EFNs and ant traits across ant species and extended this phenotypic interface to characterize local situations of phenotypic matching and mismatching at the population level. Two distinct types of phenotypic matching emerged throughout populations: (1 a population with smaller ants (Crematogaster crinosa matched with low abundance of EFNs; and (2 seven populations with bigger ants (Camponotus species matched with higher EFN abundances. Three matched populations showed the highest plant performance and narrower variance of EFN abundance, representing potential plant evolutionary hotspots. Cases of mismatched and matched populations with the lowest performance were associated

  7. Interactions between extrafloral nectaries, ants (Hymenoptera: Formicidae), and other natural enemies affect biological control of Grapholita molesta (Lepidoptera: Tortricidae) on peach (Rosales: Rosaceae).

    Science.gov (United States)

    Mathews, Clarissa R; Bottrell, Dale G; Brown, Mark W

    2011-02-01

    Extrafloral nectaries (EFNs) are reported to benefit some plants when ants (Hymenoptera: Formicidae) use their secretions and fend off herbivores, but in some cases resulting competitive interactions may reduce biological control of specific herbivores. This research examined the interactions between ants and other natural enemies associated with the EFNs of peach [Prunus persica (L.) Batcsh] and the implications for biological control of a key pest, the oriental fruit moth [Grapholita molesta (Busck)]. Studies using sentinel G. molesta placed on peach trees ('Lovell' cultivar) with EFNs present and absent revealed that several natural enemy groups associated with the EFNs contribute to reductions in G. molesta eggs, larvae, and pupae in peach orchards. Ants on trees with EFNs antagonized the G. molesta egg parasitoid Trichogramma minutum (Riley), but the ants were crucial in reducing G. molesta in both the larval and pupal stages. Overall, individual trees with EFNs experienced higher ant and other (nonant) natural enemy densities and subsequent pest reductions, as compared with trees without EFNs. However, the implications of EFN-natural enemy-pest interactions to orchard-level biological control will likely depend on local G. molesta population dynamics. © 2011 Entomological Society of America

  8. The role of jasmonates in floral nectar secretion.

    Directory of Open Access Journals (Sweden)

    Venkatesan Radhika

    Full Text Available Plants produce nectar in their flowers as a reward for their pollinators and most of our crops depend on insect pollination, but little is known on the physiological control of nectar secretion. Jasmonates are well-known for their effects on senescence, the development and opening of flowers and on plant defences such as extrafloral nectar. Their role in floral nectar secretion has, however, not been explored so far. We investigated whether jasmonates have an influence on floral nectar secretion in oil-seed rape, Brassica napus. The floral tissues of this plant produced jasmonic acid (JA endogenously, and JA concentrations peaked shortly before nectar secretion was highest. Exogenous application of JA to flowers induced nectar secretion, which was suppressed by treatment with phenidone, an inhibitor of JA synthesis. This effect could be reversed by additional application of JA. Jasmonoyl-isoleucine and its structural mimic coronalon also increased nectar secretion. Herbivory or addition of JA to the leaves did not have an effect on floral nectar secretion, demonstrating a functional separation of systemic defence signalling from reproductive nectar secretion. Jasmonates, which have been intensively studied in the context of herbivore defences and flower development, have a profound effect on floral nectar secretion and, thus, pollination efficiency in B. napus. Our results link floral nectar secretion to jasmonate signalling and thereby integrate the floral nectar secretion into the complex network of oxylipid-mediated developmental processes of plants.

  9. The effect of herbivory on temporal and spatial dynamics of foliar nectar production in cotton and castor

    NARCIS (Netherlands)

    Wäckers, F.L.; Zuber, D.; Wunderlin, R.; Keller, F.

    2001-01-01

    The effects of feeding Spodoptera littoralis(Boisd.) (Lepidoptera: Noctuidae) larvae on the quantity and distribution of extrafloral nectar production by leaves of castor (Ricinus communis) and cotton (Gossypium herbaceum) were investigated. Following larval feeding, the total volume of nectar secre

  10. The effect of herbivory on temporal and spatial dynamics of foliar nectar production in cotton and castor

    NARCIS (Netherlands)

    Wäckers, F.L.; Zuber, D.; Wunderlin, R.; Keller, F.

    2001-01-01

    The effects of feeding Spodoptera a littoralis (Boisd.) (Lepidoptera: Noctuidae) larvae on the quantity and distribution of extrafloral nectar production by leaves of castor ((Ricinus communis) and cotton (Gossypium herbaceum) were investigated. Following larval feeding, the total volume of nectar s

  11. Tree-Dwelling Ants: Contrasting Two Brazilian Cerrado Plant Species without Extrafloral Nectaries

    Directory of Open Access Journals (Sweden)

    Jonas Maravalhas

    2012-01-01

    Full Text Available Ants dominate vegetation stratum, exploiting resources like extrafloral nectaries (EFNs and insect honeydew. These interactions are frequent in Brazilian cerrado and are well known, but few studies compare ant fauna and explored resources between plant species. We surveyed two cerrado plants without EFNs, Roupala montana (found on preserved environments of our study area and Solanum lycocarpum (disturbed ones. Ants were collected and identified, and resources on each plant noted. Ant frequency and richness were higher on R. montana (67%; 35 spp than S. lycocarpum (52%; 26, the occurrence of the common ant species varied between them, and similarity was low. Resources were explored mainly by Camponotus crassus and consisted of scale insects, aphids, and floral nectaries on R. montana and two treehopper species on S. lycocarpum. Ants have a high diversity on cerrado plants, exploring liquid and prey-based resources that vary in time and space and affect their presence on plants.

  12. Ants have a negative rather than a positive effect on extrafloral nectaried Crotalaria pallida performance

    Science.gov (United States)

    Pereira, Marcela Fernandes; Trigo, José Roberto

    2013-08-01

    Crotalaria pallida (Fabaceae) is a pantropical plant with extrafloral nectaries (EFNs) near the reproductive structures. EFN-visiting ants attack and remove arctiid moth Utetheisa ornatrix larvae, the main pre-dispersal seed predator, but the impact of ants on C. pallida fitness is unknown. To assess this impact, we controlled ant presence on plants and evaluated the reproductive output of C. pallida with and without ants. Predatory wasps also visit EFNs, prey upon U. ornatrix larvae, and may be driven out by ants during EFN feeding. Does this agonistic interaction affect the multitrophic interaction outcome? We found it difficult to evaluate the effect of both visitors because cages excluding wasps affect plant growth and do not allow U. ornatrix oviposition. Therefore, we verified whether ant presence inhibited wasp EFN visitation and predicted that (1) if ants confer a benefit for C. pallida, any negative effect of ants on wasps would be negligible for the plant because ants would be the best guardians, and (2) if ants are poor guardians, they would negatively affect wasps and negatively impact the fitness of C. pallida. Surprisingly, we found that the number of seeds/pods significantly increased, ca. 4.7 times, after ant removal. Additionally, we unexpectedly verified that controls showed a higher percentage of herbivore bored pods than ant-excluded plants. We found that wasps spent less time visiting EFNs patrolled by ants (ca. 299 s less). These results support our second prediction and suggest that the outcome of multitrophic interactions may vary with natural enemy actors.

  13. Time-course proteome analysis of developing extrafloral nectaries of Ricinus communis.

    Science.gov (United States)

    Shah, Mohibullah; Teixeira, Fabiano M; Soares, Emanoella L; Soares, Arlete A; Carvalho, Paulo C; Domont, Gilberto B; Thornburg, Robert W; Nogueira, Fábio C S; Campos, Francisco A P

    2016-02-01

    Floral and extrafloral nectaries are unique organs that secrete energy rich chemical components, but their contribution for nectar production is largely unknown. Here, we present the first comparative proteome dataset of four developmental stages of the extrafloral nectaries from castor plant (Ricinus communis), an important biofuel crop. Respectively, from stage I-IV, we identified 626, 613, 449 and 356 proteins, respectively, summing up 882 nonredundant proteins. Surprisingly, we identified two isoforms of the potent toxin ricin, indicating that ricin expression is not limited to seeds, but it may serve a general defense purpose for the castor plant. To date, this is the most complete dataset of proteins either from floral or extrafloral nectaries, thus contributing to lay the foundations for investigations on their ecological and evolutionary importance. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. EFNS guidelines on neurostimulation therapy for neuropathic pain

    DEFF Research Database (Denmark)

    EFNS Panel on Neuropathic Pain, Vienna; Cruccu, Giorgio; Aziz, T. Z.

    2007-01-01

    and to produce relevant recommendations. We searched the literature from 1968 to 2006, looking for neurostimulation in neuropathic pain conditions, and classified the trials according to the EFNS scheme of evidence for therapeutic interventions. Spinal cord stimulation (SCS) is efficacious in failed back surgery...

  15. EFNS guidelines for the diagnosis and management of Alzheimer's disease.

    Science.gov (United States)

    Hort, J; O'Brien, J T; Gainotti, G; Pirttila, T; Popescu, B O; Rektorova, I; Sorbi, S; Scheltens, P

    2010-10-01

    In 2008 a task force was set up to develop a revision of the European Federation of the Neurological Societies (EFNS) guideline for the diagnosis and management of Alzheimer's disease (AD) and other disorders associated with dementia, published in early 2007. The aim of this revised international guideline was to present a peer-reviewed evidence-based statement for the guidance of practice for clinical neurologists, geriatricians, psychiatrists, and other specialist physicians responsible for the care of patients with AD. Mild cognitive impairment and non-Alzheimer dementias are not included in this guideline. The task force working group reviewed evidence from original research articles, meta-analysis, and systematic reviews, published before May 2009. The evidence was classified and consensus recommendations graded (A, B, or C) according to the EFNS guidance. Where there was a lack of evidence, but clear consensus, good practice points were provided. The recommendations for clinical diagnosis, blood tests, neuropsychology, neuroimaging, electroencephalography, cerebrospinal fluid (CSF) analysis, genetic testing, disclosure of diagnosis, treatment of AD, behavioural and psychological symptoms in dementia, legal issues, counselling and support for caregivers were all revised as compared with the previous EFNS guideline. A number of new recommendations and good practice points are made, namely in CSF, neuropsychology, neuroimaging and reviewing non-evidence based therapies. The assessment, interpretation, and treatment of symptoms, disability, needs, and caregiver stress during the course of AD require the contribution of many different professionals. These professionals should adhere to these guideline to improve the diagnosis and management of AD. © 2010 The Author(s). European Journal of Neurology © 2010 EFNS.

  16. EFNS/MDS-ES/ENS recommendations for the diagnosis of Parkinson's disease

    NARCIS (Netherlands)

    Berardelli, A.; Wenning, G.K.; Antonini, A.; Berg, D. van den; Bloem, B.R.; Bonifati, V.; Brooks, D.; Burn, D.J.; Colosimo, C.; Fanciulli, A.; Ferreira, J.; Gasser, T.; Grandas, F.; Kanovsky, P.; Kostic, V.; Kulisevsky, J.; Oertel, W.; Poewe, W.; Reese, J.P.; Relja, M.; Ruzicka, E.; Schrag, A.; Seppi, K.; Taba, P.; Vidailhet, M.

    2013-01-01

    BACKGROUND: A Task Force was convened by the EFNS/MDS-ES Scientist Panel on Parkinson's disease (PD) and other movement disorders to systemically review relevant publications on the diagnosis of PD. METHODS: Following the EFNS instruction for the preparation of neurological diagnostic guidelines, re

  17. Common-garden experiments reveal geographical variation in the interaction among Crotalaria pallida (Leguminosae: Papilionideae), Utetheisa ornatrix L. (Lepidoptera: Arctiidae), and extrafloral nectary visiting ants.

    Science.gov (United States)

    Franco, M S; Cogni, R

    2013-06-01

    The study of geographical variation is a key approach to understand evolution of ecological interactions. We investigated geographical variation in the interaction among Crotalaria pallida (Leguminosae: Papilionideae), its specialized herbivore, Utetheisa ornatrix L. (Lepidoptera: Arctiidae), and ants attracted to extrafloral nectaries (EFNs). First, we used common-garden experiments with plants collected in different sites at different geographical scales to test for differences among populations in C. pallida attractiveness to ants. When we compared three populations from Southeast Brazil (150 km apart), the number of visiting ants per plant, and the percent of termite baits attacked by ants, were significantly different among plant populations. In a comparison of populations from SE Brazil and Florida (USA), there was no significant difference between the populations in the number of ants per plant or the frequency of baits attacked. Second, we tested in a common garden if U. ornatrix larvae present any behavior to avoid ant predation, and if there were genetic differences among populations. We observed that most larvae moved away from the vicinity of the EFNs (flowers and fruits) to the plant leaves. Of the larvae that moved to leaves, only 10% were attacked by ants while 89% of larvae that stayed near the fruit/flower were attacked. There was a significant difference among populations in the frequency of larvae that moved to the leaves and the frequency of larvae attacked by ants. We discuss the possible causes of the geographical differences observed and propose future research directions in this system.

  18. Floral nectar guide patterns discourage nectar robbing by bumble bees.

    Directory of Open Access Journals (Sweden)

    Anne S Leonard

    Full Text Available Floral displays are under selection to both attract pollinators and deter antagonists. Here we show that a common floral trait, a nectar guide pattern, alters the behavior of bees that can act opportunistically as both pollinators and as antagonists. Generally, bees access nectar via the floral limb, transporting pollen through contact with the plant's reproductive structures; however bees sometimes extract nectar from a hole in the side of the flower that they or other floral visitors create. This behavior is called "nectar robbing" because bees may acquire the nectar without transporting pollen. We asked whether the presence of a symmetric floral nectar guide pattern on artificial flowers affected bumble bees' (Bombus impatiens propensity to rob or access nectar "legitimately." We discovered that nectar guides made legitimate visits more efficient for bees than robbing, and increased the relative frequency of legitimate visits, compared to flowers lacking nectar guides. This study is the first to show that beyond speeding nectar discovery, a nectar guide pattern can influence bees' flower handling in a way that could benefit the plant.

  19. EFNS guidelines on pharmacological treatment of neuropathic pain

    DEFF Research Database (Denmark)

    Attal, Nadine; Cruccu, G; Haanpää, M

    2006-01-01

    Neuropathic pain treatment remains unsatisfactory despite a substantial increase in the number of trials. This EFNS Task Force aimed at evaluating the existing evidence about the pharmacological treatment of neuropathic pain. Studies were identified using first the Cochrane Database then Medline...... neuralgia, other peripheral neuropathic pain states and multiple-aetiology neuropathic pains. The main peripheral pain conditions respond similarly well to tricyclic antidepressants, gabapentin, and pregabalin, but some conditions, such as HIV-associated polyneuropathy, are more refractory. There are too...... evaluated. Effects on pain symptoms/signs, quality of life and comorbidities were particularly searched for. Most of the randomized controlled trials included patients with postherpetic neuralgia (PHN) and painful polyneuropathies (PPN) mainly caused by diabetes. These trials provide level A evidence...

  20. Ontogenia dos nectários extraflorais de Triumfetta semitriloba (tiliaceae Extrafloral nectary ontogeny of Triumfetta semitriloba (Tiliaceae

    Directory of Open Access Journals (Sweden)

    C.A.E. Leitão

    2002-12-01

    Full Text Available Triumfetta semitriloba é uma planta daninha que apresenta nectários florais e extraflorais, sendo os últimos visitados por formigas que protegem a planta do ataque de insetos. O presente trabalho teve como objetivo descrever a ontogenia dos nectários extraflorais de T. semitriloba. Para isso, amostras de nectários em quatro estádios de desenvolvimento foram obtidas de plantas adultas, sendo o material submetido às técnicas usuais de obtenção de lâminas permanentes. Os nectários iniciam o seu desenvolvimento precocemente, com o surgimento de uma concavidade voltada para a face adaxial. Posteriormente, células protodérmicas dão origem a tricomas nectaríferos clavados, e subjacente se desenvolve um parênquima nectarífero vascularizado por floema e xilema, características comuns em nectários encontrados entre as Malvales. As células da cabeça dos tricomas nectaríferos apresentam vacúolos com compostos fenólicos, que possivelmente desempenham papel ecológico. Plastídios não ocorrem nos tricomas e são inconspícuos no parênquima nectarífero, o que possivelmente indica a sua importância secundária na secreção do néctar. O nectário senescente apresenta relativamente menos tricomas nectaríferos, que são penetrados por hifas de fungos que recobrem a concavidade nesse estádio. Para entendimento dos processos de secreção e eliminação do néctar, são necessários estudos ao microscópio eletrônico de transmissão.Triumfetta semitriloba is a weed displaying floral and extrafloral nectaries, the latter being visited by ants that protect the plants. The objective of this work was to describe the ontogeny of the extrafloral nectaries of T. semitriloba, using nectary samples obtained from adult plants, in four developmental stages. The material was submitted to the usual techniques to obtain permanent slides. The nectaries initiate their development precociously, with the appearance of one concavity turned to the

  1. Pseudomyrmex ants and Acacia host plants join efforts to protect their mutualism from microbial threats

    OpenAIRE

    González-Teuber, Marcia; Heil, Martin

    2010-01-01

    Plants express numerous ‘pathogenesis-related’ (PR) proteins to defend themselves against pathogen infection. We recently discovered that PR-proteins such as chitinases, glucanases, peroxidases and thaumatin-like proteins are also functioning in the protection of extra-floral nectar (EFN) of Mexican Acacia myrmecophytes. These plants produce EFN, cellular food bodies and nesting space to house defending ant species of the genus Pseudomyrmex. More than 50 PR-proteins were discovered in this EF...

  2. Exploring whether and how ants affect reproductive fitness in Senna mexicana var. chapmanii

    Science.gov (United States)

    Extrafloral nectar (EFN) mediates food-for-protection mutualisms between plants and ants. Ant-plant mutualisms are keystone associations, occurring within a complex web of biotic interactions. As such, these interactions may affect plant fitness in a number of ways, both positive and negative. In S...

  3. No time for candy: passionfruit (Passiflora edulis) plants down-regulate damage-induced extra floral nectar production in response to light signals of competition.

    Science.gov (United States)

    Izaguirre, Miriam M; Mazza, Carlos A; Astigueta, María S; Ciarla, Ana M; Ballaré, Carlos L

    2013-09-01

    Plant fitness is often defined by the combined effects of herbivory and competition, and plants must strike a delicate balance between their ability to capture limiting resources and defend against herbivore attack. Many plants use indirect defenses, such as volatile compounds and extra floral nectaries (EFN), to attract canopy arthropods that are natural enemies of herbivorous organisms. While recent evidence suggests that upon perception of low red to far-red (R:FR) ratios, which signal the proximity of competitors, plants down-regulate resource allocation to direct chemical defenses, it is unknown if a similar phytochrome-mediated response occurs for indirect defenses. We evaluated the interactive effects of R:FR ratio and simulated herbivory on nectar production by EFNs of passion fruit (Passiflora edulis f. flavicarpa). The activity of petiolar EFNs dramatically increased in response to simulated herbivory and hormonal treatment with methyl jasmonate (MeJA). Low R:FR ratios, which induced a classic "shade-avoidance" repertoire of increased stem elongation in P. edulis, strongly suppressed the EFN response triggered by simulated herbivory or MeJA application. Strikingly, the EFN response to wounding and light quality was localized to the branches that received the treatments. In vines like P. edulis, a local response would allow the plants to precisely adjust their light harvesting and defense phenotypes to the local conditions encountered by individual branches when foraging for resources in patchy canopies. Consistent with the emerging paradigm that phytochrome regulation of jasmonate signaling is a central modulator of adaptive phenotypic plasticity, our results demonstrate that light quality is a strong regulator of indirect defenses.

  4. Structure of the extrafloral nectaries of Vicia (L. Fabaceae

    Directory of Open Access Journals (Sweden)

    Małgorzata Stpiczyńska

    2013-12-01

    Full Text Available Extrafloral nectaries on the abaxial surface of stipules were investigated in the Vicia angustifolia, Vicia sativa, Vicia sepium and Vicia grandiflora. In V. angustifolia nectaries were also located on the calyx surface. Nectaries were consisted of secretory hairs and 2-31ayers of subepidermal cells. Secretory hair was built of four cells of head, one stalk cell and basal cell. Head cells showed character of transfer cells because of walls ingrowths and dense cytoplasm with numerous mitochondria.

  5. Protection of Vochysia elliptica (Vochysiaceae) by a nectar-thieving ant.

    Science.gov (United States)

    Romero, G Q

    2002-05-01

    Vochysia elliptica (Vochysiaceae) is a shrubby plant, which does not have EFNs. Camponotus ants thieve nectar, and can decrease plant fitness by making flowers less attractive to pollinators. However, ants remove herbivores, wHich can be beneficial. Results show that plants from which ants were excluded had lower rates of termite (simulated herbivore) removal than did plants visited by ants. Plants accessible to ants showed higher rates of termite removal in the base of leaves and in the inflorescence, than in the tip of leaves. This occurs because ants must pass through the principal axis to reach the inflorescence. Conclusive results of this cost/benefit analysis of the Camponotus sp. presence for V. elliptica can be obtained, with experimental manipulations.

  6. Protection of Vochysia elliptica (Vochysiaceae by a nectar-thieving ant

    Directory of Open Access Journals (Sweden)

    G. Q. ROMERO

    Full Text Available Vochysia elliptica (Vochysiaceae is a shrubby plant, which does not have EFNs. Camponotus ants thieve nectar, and can decrease plant fitness by making flowers less attractive to pollinators. However, ants remove herbivores, wich can be beneficial. Results show that plants from which ants were excluded had lower rates of termite (simulated herbivore removal than did plants visited by ants. Plants accessible to ants showed higher rates of termite removal in the base of leaves and in the inflorescence, than in the tip of leaves. This occurs because ants must pass through the principal axis to reach the inflorescence. Conclusive results of this cost/benefit analysis of the Camponotus sp. presence for V. elliptica can be obtained, with experimental manipulations.

  7. EFNS guidelines for the molecular diagnosis of neurogenetic disorders: motoneuron, peripheral nerve and muscle disorders.

    LENUS (Irish Health Repository)

    Burgunder, J-M

    2011-02-01

    These EFNS guidelines on the molecular diagnosis of motoneuron disorders, neuropathies and myopathies are designed to summarize the possibilities and limitations of molecular genetic techniques and to provide diagnostic criteria for deciding when a molecular diagnostic work-up is indicated.

  8. EFN-4 functions in LAD-2-mediated axon guidance in Caenorhabditis elegans.

    Science.gov (United States)

    Dong, Bingyun; Moseley-Alldredge, Melinda; Schwieterman, Alicia A; Donelson, Cory J; McMurry, Jonathan L; Hudson, Martin L; Chen, Lihsia

    2016-04-01

    During development of the nervous system, growing axons rely on guidance molecules to direct axon pathfinding. A well-characterized family of guidance molecules are the membrane-associated ephrins, which together with their cognate Eph receptors, direct axon navigation in a contact-mediated fashion. InC. elegans, the ephrin-Eph signaling system is conserved and is best characterized for their roles in neuroblast migration during early embryogenesis. This study demonstrates a role for the C. elegans ephrin EFN-4 in axon guidance. We provide both genetic and biochemical evidence that is consistent with the C. elegans divergent L1 cell adhesion molecule LAD-2 acting as a non-canonical ephrin receptor to EFN-4 to promote axon guidance. We also show that EFN-4 probably functions as a diffusible factor because EFN-4 engineered to be soluble can promote LAD-2-mediated axon guidance. This study thus reveals a potential additional mechanism for ephrins in regulating axon guidance and expands the repertoire of receptors by which ephrins can signal.

  9. Domacios y nectarios extraflorales en Bignoniáceas: componentes vegetales de una interacción mutualística Domatia and extrafloral nectaries in Bignoniaceae: two components of a mutualistic interaction

    Directory of Open Access Journals (Sweden)

    Ana M Gonzalez

    2011-12-01

    Full Text Available Las plantas presentan relaciones mutualísticas con insectos a cambio del control de sus herbívoros u hongos patógenos; por medio de los domacios les ofrecen albergue y mediante la secreción de néctar de nectarios extraflorales les brindan alimento. Se examinó la anatomía foliar en 52 especies de Bignoniaceae con microscopía óptica y electrónica de barrido, con el objetivo de describir los domacios y los nectarios extraflorales. Los domacios presentes son de dos tipos: mechones de pelos y bolsillos, siendo un carácter taxonómico útil en varias especies. Los nectarios extraflorales se encuentran en todas las especies, ubicándose en diversas posiciones: a lo largo de la vena media, asociados a los domacios o agrupados en campos glandulares, que pueden ser foliares o interpeciolares. Las Bignoniaceae presentan simultáneamente domacios y nectarios extraflorales en sus hojas, los cuales se describen como componentes vegetales de un probable mecanismo de defensa indirecta.Plants have mutualistic relationships with insects in two ways: through domatia provide housing of predators, and extrafloral nectaries secreting nectar and provide food in exchange for control of herbivores or fungal pathogens. The foliar anatomy of 52 species of Bignoniaceae was examined by light and scanning electron microscopy, in order to describe the different types of domatia and extrafloral nectaries. Two types of domatia were observed: small hair-tufts and pockets; the presence and type of domatia represents important taxonomic characters in Bignoniaceae. Extrafloral nectaries are found in all studied species. They are located in different positions: along the midvein, associated with domatia, or grouped in glandular fields, either in leaf or interpetiolar. The Bignoniaceae have simultaneously domatia and extrafloral nectaries on their leaves, these features are described as plant components in a probable mechanism of indirect defense.

  10. New record of predatory ladybird beetle (Coleoptera, Coccinellidae feeding on extrafloral nectaries

    Directory of Open Access Journals (Sweden)

    Lúcia M. Almeida

    2011-09-01

    Full Text Available New record of predatory ladybird beetle (Coleoptera, Coccinellidae feeding on extrafloral nectaries. Feeding by Exoplectra miniata (Germar on extrafloral nectaries of Inga edulis Mart. was observed in Nova Friburgo, Rio de Janeiro, Brazil. This is the first record of this behavior for Exoplectrini.

  11. EFNS-ENS Guidelines on the diagnosis and management of disorders associated with dementia.

    Science.gov (United States)

    Sorbi, S; Hort, J; Erkinjuntti, T; Fladby, T; Gainotti, G; Gurvit, H; Nacmias, B; Pasquier, F; Popescu, B O; Rektorova, I; Religa, D; Rusina, R; Rossor, M; Schmidt, R; Stefanova, E; Warren, J D; Scheltens, P

    2012-09-01

    The last version of the EFNS dementia guidelines is from 2007. In 2010, the revised guidelines for Alzheimer's disease (AD) were published. The current guidelines involve the revision of the dementia syndromes outside of AD, notably vascular cognitive impairment, frontotemporal lobar degeneration, dementia with Lewy bodies, corticobasal syndrome, progressive supranuclear palsy, Parkinson's disease dementia, Huntington's disease, prion diseases, normal-pressure hydrocephalus, limbic encephalitis and other toxic and metabolic disorders. The aim is to present a peer-reviewed evidence-based statement for the guidance of practice for clinical neurologists, geriatricians, psychiatrists and other specialist physicians responsible for the care of patients with dementing disorders. It represents a statement of minimum desirable standards for practice guidance. The task force working group reviewed evidence from original research articles, meta-analyses and systematic reviews, published by June 2011. The evidence was classified (I, II, III, IV) and consensus recommendations graded (A, B, or C) according to the EFNS guidance. Where there was a lack of evidence, but clear consensus, good practice points were provided. New recommendations and good practice points are made for clinical diagnosis, blood tests, neuropsychology, neuroimaging, electroencephalography, cerebrospinal fluid (CSF) analysis, genetic testing, disclosure of diagnosis, treatment of behavioural and psychological symptoms in dementia, legal issues, counselling and support for caregivers. All recommendations were revised as compared with the previous EFNS guidelines. The specialist neurologist together with primary care physicians play an important role in the assessment, interpretation and treatment of symptoms, disability and needs of dementia patients. © 2012 The Author(s) European Journal of Neurology © 2012 EFNS.

  12. Ontogênese, anatomia e ultra-estrutura dos nectários extraflorais de Hymenaea stigonocarpa Mart. ex Hayne (Fabaceae - Caesalpinioideae Ontogenesis, anatomy, and ultrastructure of Hymenaea stigonocarpa Mart. ex Hayne (Fabaceae - Caesalpinioideae extrafloral nectaries

    Directory of Open Access Journals (Sweden)

    Élder Antônio Sousa Paiva

    2006-06-01

    Full Text Available O jatobá-do-cerrado (Hymenaea stigonocarpa Mart. ex Hayne apresenta nectários extraflorais (NEFs, os quais são descritos pela primeira vez no gênero. Neste trabalho foram estudadas a distribuição, ontogênese, estrutura e ultra-estrutura dos nectários extraflorais (NEFs. Amostras de folhas em várias fases de desenvolvimento foram coletadas, fixadas e processadas para estudos em microscopia de luz e eletrônica de transmissão e varredura, segundo técnicas convencionais. Testes histoquímicos foram empregados para determinar a natureza química da secreção. Os NEFs estão distribuídos por todo o limbo, sendo mais concentrados nos terços basal e médio de cada folíolo. Estes nectários são embutidos no mesofilo, apresentam tecido secretor envolvido por uma endoderme e são vascularizados por xilema e floema. A atividade secretora dos NEFs é limitada à fase juvenil da folha. Nas folhas mais velhas, os NEFs tornam-se não funcionais. O tecido secretor dos NEFs é formado a partir da protoderme, enquanto a endoderme tem origem no meristema fundamental. No tecido secretor de nectários funcionais as células apresentam citoplasma denso, núcleo volumoso, mitocôndrias, plastídios com sistema de membranas pouco desenvolvido, gotas de óleo dispersas no citosol, dictiossomos e segmentos de retículo endoplasmático liso. A secreção é liberada por meio de rupturas cuticulares e apresenta polissacarídeos e lipídios.Hymenaea stigonocarpa Mart. ex Hayne, known as "jatobá-do-cerrado" has extrafloral nectaries (EFNs, which are reported for the first time in Hymenaea genus. In this research the origin, distribution, structure, and ultrastructure of the EFNs were studied. Samples of leaflets at different developmental stages were collected, fixed and processed by standard methods for analyses at light and electronic microscopes; histochemical tests were employed to determine the nature of secretion products. EFNs are distributed all over

  13. Carbon isotope analysis in apple nectar beverages

    Directory of Open Access Journals (Sweden)

    Ricardo Figueira

    2013-03-01

    Full Text Available The aims of this study were to use the isotope analysis method to quantify the carbon of C3 photosynthetic cycle in commercial apple nectars and to determine the legal limit to identify the beverages that do not conform to the safety standards established by the Brazilian Ministry of Agriculture, Livestock and Food Supply. These beverages (apple nectars were produced in the laboratory according to the Brazilian legislation. Adulterated nectars were also produced with an amount of pulp juice below the permitted threshold limit value. The δ13C values of the apple nectars and their fractions (pulp and purified sugar were measured to quantify the C3 source percentage. In order to demonstrate the existence of adulteration, the values found were compared to the limit values established by the Brazilian Law. All commercial apple nectars analyzed were within the legal limits, which enabled to identify the nectars that were in conformity with the Brazilian Law. The isotopic methodology developed proved efficient to quantify the carbon of C3 origin in commercial apple nectars.

  14. Diverse nectar robbers on Alpinia roxburghii Sweet (Zingiberaceae

    Directory of Open Access Journals (Sweden)

    Xiaobao Deng

    2015-09-01

    Full Text Available This study records for the first time three mammal species as nectar robbers on the ginger Alpinia roxburghii Sweet. We examined the behavior of nectar robbers and compared with earlier studies on a single plant species. We recorded seven species of nectar robbers: three squirrels, one bird, and three bees. Timing of robbing nectars were similar; however, robbing behavior differed among robbers. In particular, squirrels damaged the flower parts while robbing the nectar.

  15. EFNS Task Force on Teaching of Neuroimaging in Neurology Curricula in Europe : present status and recommendations for the future

    NARCIS (Netherlands)

    Pantano, P; Chollet, F; Paulson, O; von Kummer, R; Laihinen, A; Leenders, K; Yancheva, S

    2001-01-01

    A Task Force on 'Teaching of Neuroimaging in Neurology Curricula in Europe' was appointed in September 1998 by the education committee of the European Federation of Neurological Societies (EFNS) in order to: (1) examine the present status of teaching of neuroimaging in the training of neurology in E

  16. Partner manipulation stabilises a horizontally transmitted mutualism.

    Science.gov (United States)

    Heil, Martin; Barajas-Barron, Alejandro; Orona-Tamayo, Domancar; Wielsch, Natalie; Svatos, Ales

    2014-02-01

    Mutualisms require protection from non-reciprocating exploiters. Pseudomyrmex workers that engage in an obligate defensive mutualism with Acacia hosts feed exclusively on the sucrose-free extrafloral nectar (EFN) that is secreted by their hosts, a behaviour linking ant energy supply directly to host performance and thus favouring reciprocating behaviour. We tested the hypothesis that Acacia hosts manipulate this digestive specialisation of their ant mutualists. Invertase (sucrose hydrolytic) activity in the ant midguts was inhibited by chitinase, a dominant EFN protein. The inhibition occurred quickly in cell-free gut liquids and in native gels and thus likely results from an enzyme-enzyme interaction. Once a freshly eclosed worker ingests EFN as the first diet available, her invertase becomes inhibited and she, thus, continues feeding on host-derived EFN. Partner manipulation acts at the phenotypic level and means that one partner actively controls the phenotype of the other partner to enhance its dependency on host-derived rewards.

  17. New functions for secondary compounds in floral nectar

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ Floral nectar, which is mainly composed of sugar, plays a major role in attracting pollinators. However, many studies show that most of the nectar also contains antiherbivore secondary compounds, such as phenolics, which could keep away some flower visitors.

  18. Sodium and potassium concentrations in floral nectars in relation to ...

    African Journals Online (AJOL)

    1989-08-03

    Aug 3, 1989 ... nectar ion concentrations in carpenter bee and hummingbird flowers. ..... bee foragers gather nectar for the colony as a whole. ... solutions to honey bees foraging at a feeder. Artificial food sources have been used extensively ...

  19. EFNS guidelines on the use of skin biopsy in the diagnosis of peripheral neuropathy.

    Science.gov (United States)

    Lauria, G; Cornblath, D R; Johansson, O; McArthur, J C; Mellgren, S I; Nolano, M; Rosenberg, N; Sommer, C

    2005-10-01

    Skin biopsy has become a widely used tool to investigate small calibre sensory nerves including somatic unmyelinated intraepidermal nerve fibres (IENF), dermal myelinated nerve fibres, and autonomic nerve fibres in peripheral neuropathies and other conditions. Different techniques for tissue processing and nerve fibre evaluation have been used. In March 2004, a Task Force was set up under the auspices of the European Federation of Neurological Societies (EFNS) with the aim of developing guidelines on the use of skin biopsy in the diagnosis of peripheral neuropathies. We searched the Medline database from 1989, the year of the first publication describing the innervation of human skin using immunostaining with anti-protein-gene-product 9.5 (PGP 9.5) antibodies, to 31 March 2005. All pertinent papers were rated according to the EFNS guidance. The final version of the guidelines was elaborated after consensus amongst members of the Task Force was reached. For diagnostic purposes in peripheral neuropathies, we recommend performing a 3-mm punch skin biopsy at the distal leg and quantifying the linear density of IENF in at least three 50-mum thick sections per biopsy, fixed in 2% PLP or Zamboni's solution, by bright-field immunohistochemistry or immunofluorescence with anti-PGP 9.5 antibodies (level A recommendation). Quantification of IENF density closely correlated with warm and heat-pain threshold, and appeared more sensitive than sensory nerve conduction study and sural nerve biopsy in diagnosing small-fibre sensory neuropathy. Diagnostic efficiency and predictive values of this technique were very high (level A recommendation). Confocal microscopy may be particularly useful to investigate myelinated nerve fibres, dermal receptors and dermal annex innervation. In future, the diagnostic yield of dermal myelinated nerve fibre quantification and of sweat gland innervation should be addressed. Longitudinal studies of IENF density and regeneration rate are warranted to

  20. Honeybees prefer warmer nectar and less viscous nectar, regardless of sugar concentration.

    Science.gov (United States)

    Nicolson, Susan W; de Veer, Leo; Köhler, Angela; Pirk, Christian W W

    2013-09-22

    The internal temperature of flowers may be higher than air temperature, and warmer nectar could offer energetic advantages for honeybee thermoregulation, as well as being easier to drink owing to its lower viscosity. We investigated the responses of Apis mellifera scutellata (10 colonies) to warmed 10% w/w sucrose solutions, maintained at 20-35°C, independent of low air temperatures, and to 20% w/w sucrose solutions with the viscosity increased by the addition of the inert polysaccharide Tylose (up to the equivalent of 34.5% sucrose). Honeybee crop loads increased with nectar temperature, as did the total consumption of sucrose solutions over 2 h by all bees visiting the feeders. In addition, the preference of marked honeybees shifted towards higher nectar temperatures with successive feeder visits. Crop loads were inversely proportional to the viscosity of the artificial nectar, as was the total consumption of sucrose solutions over 2 h. Marked honeybees avoided higher nectar viscosities with successive feeder visits. Bees thus showed strong preferences for both warmer and less viscous nectar, independent of changes in its sugar concentration. Bees may benefit from foraging on nectars that are warmer than air temperature for two reasons that are not mutually exclusive: reduced thermoregulatory costs and faster ingestion times due to the lower viscosity.

  1. EphA4 and EfnB2a maintain rhombomere coherence by independently regulating intercalation of progenitor cells in the zebrafish neural keel.

    Science.gov (United States)

    Kemp, Hilary A; Cooke, Julie E; Moens, Cecilia B

    2009-03-15

    During vertebrate development, the hindbrain is transiently segmented into 7 distinct rhombomeres (r). Hindbrain segmentation takes place within the context of the complex morphogenesis required for neurulation, which in zebrafish involves a characteristic cross-midline division that distributes progenitor cells bilaterally in the forming neural tube. The Eph receptor tyrosine kinase EphA4 and the membrane-bound Ephrin (Efn) ligand EfnB2a, which are expressed in complementary segments in the early hindbrain, are required for rhombomere boundary formation. We showed previously that EphA4 promotes cell-cell affinity within r3 and r5, and proposed that preferential adhesion within rhombomeres contributes to boundary formation. Here we show that EfnB2a is similarly required in r4 for normal cell affinity and that EphA4 and EfnB2a regulate cell affinity independently within their respective rhombomeres. Live imaging of cell sorting in mosaic embryos shows that both proteins function during cross-midline cell divisions in the hindbrain neural keel. Consistent with this, mosaic EfnB2a over-expression causes widespread cell sorting and disrupts hindbrain organization, but only if induced at or before neural keel stage. We propose a model in which Eph and Efn-dependent cell affinity within rhombomeres serve to maintain rhombomere organization during the potentially disruptive process of teleost neurulation.

  2. Determinants of nectar production in oilseed rape

    DEFF Research Database (Denmark)

    Enkegaard, Annie; Kryger, Per; Boelt, Birte

    2016-01-01

    With the aim of contributing to the development of models forecasting the melliferous characteristics and the potential honey yield of oilseed rape, we analyzed data on the temporal pattern of number of oilseed rape flowers, nectar secretion, sugar concentration, and weight of bee hives in relati...... by the amount of secreted sugar, as well as by the temperature conditions and the strength of the colony during flowering. Our results will assist beekeepers in predicting nectar production and sugar yield in oilseed rape and the ability of bees to exploit the sugar....

  3. Do honeybees shape the bacterial community composition in floral nectar?

    Directory of Open Access Journals (Sweden)

    Yana Aizenberg-Gershtein

    Full Text Available 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.

  4. Nectar amino acids enhance reproduction in male butterflies.

    Science.gov (United States)

    Cahenzli, Fabian; Erhardt, Andreas

    2013-01-01

    After over 30 years of research, it was recently shown that nectar amino acids increase female butterfly fecundity. However, little attention has been paid to the effect of nectar amino acids on male butterfly reproduction. Here, we show that larval food conditions (nitrogen-rich vs. nitrogen-poor host plants) and adult diet quality (nectar with or without amino acids) affected the amount of consumed nectar in Coenonympha pamphilus males. Furthermore, amino acids in the nectar diet of males increased progeny's larval hatching mass, irrespective of paternal larval reserves. Our study takes the whole reproductive cycle of male butterflies into account, and also considers the role of females in passing male nutrients to offspring, as males' realized reproduction was examined indirectly via nuptial gifts, by female performance. With this comprehensive approach, we demonstrate for the first time that nectar amino acids can improve male butterfly reproduction, supporting the old postulate that nectar amino acids generally enhance butterfly fitness.

  5. Studies on cloud stability of apricot nectar

    NARCIS (Netherlands)

    Siliha, H.A.I.

    1985-01-01

    Cloud loss behaviour in pasteurized apricot nectar was found to be different from that of other fruit juices. The cloud particles settled slowly on standing and a gel formed. On standing for a longer period the gel contracts and a clear supernatant layer which can be considered partly as syneresis w

  6. Nectar robbery by a hermit hummingbird

    DEFF Research Database (Denmark)

    Maruyama, Pietro Kiyoshi; Vizentin-Bugoni, Jeferson; Dalsgaard, Bo

    2015-01-01

    Interactions between flowers and their visitors span the spectrum from mutualism to antagonism. The literature is rich in studies focusing on mutualism, but nectar robbery has mostly been investigated using phytocentric approaches focused on only a few plant species. To fill this gap, we studied ...

  7. Studies on cloud stability of apricot nectar

    NARCIS (Netherlands)

    Siliha, H.A.I.

    1985-01-01

    Cloud loss behaviour in pasteurized apricot nectar was found to be different from that of other fruit juices. The cloud particles settled slowly on standing and a gel formed. On standing for a longer period the gel contracts and a clear supernatant layer which can be considered partly as

  8. 欧洲神经病学联盟关于视神经脊髓炎诊治的指南%EFNS guidelines on diagnosis and management of neuromyelitis optica

    Institute of Scientific and Technical Information of China (English)

    Sellner J; Boggild M; Clanet M; 李海峰; 徐雁

    2010-01-01

    @@ 2010年6月的Eur J Neurol杂志发表了由欧洲神经病学联盟(EFNS)多发性硬化(MS)/脱髓鞘疾病专家组(EFNS Scientific Panel on Multiple Sclerosis/Demyelinating Disorders)起草并由EFNS的科学委员会(Scientific Com-mittee of the EFNS)通过的视神经脊髓炎(NMO)诊治指南.

  9. Wideband pulse amplifiers for the NECTAr chip

    Science.gov (United States)

    Sanuy, A.; Delagnes, E.; Gascon, D.; Sieiro, X.; Bolmont, J.; Corona, P.; Feinstein, F.; Glicenstein, J.-F.; Naumann, C. L.; Nayman, P.; Ribó, M.; Tavernet, J.-P.; Toussenel, F.; Vincent, P.; Vorobiov, S.

    2012-12-01

    The NECTAr collaboration's FE option for the camera of the CTA is a 16 bits and 1-3 GS/s sampling chip based on analog memories including most of the readout functions. This works describes the input amplifiers of the NECTAr ASIC. A fully differential wideband amplifier, with voltage gain up to 20 V/V and a BW of 400 MHz. As it is impossible to design a fully differential OpAmp with an 8 GHz GBW product in a 0.35 CMOS technology, an alternative implementation based on HF linearized transconductors is explored. The output buffer is a class AB miller operational amplifier, with special non-linear current boost.

  10. Wideband pulse amplifiers for the NECTAr chip

    Energy Technology Data Exchange (ETDEWEB)

    Sanuy, A., E-mail: asanuy@ecm.ub.es [Dept. AM i Dept. ECM, Institut de Ciencies del Cosmos (ICC), Universitat de Barcelona. Marti i Franques 1, E08028, Barcelona (Spain); Delagnes, E. [IRFU/DSM/CEA, CE-Saclay, Bat. 141 SEN Saclay, F-91191, Gif-sur-Yvette (France); Gascon, D. [Dept. AM i Dept. ECM, Institut de Ciencies del Cosmos (ICC), Universitat de Barcelona. Marti i Franques 1, E08028, Barcelona (Spain); Sieiro, X. [Departament d' Electronica, Universitat de Barcelona. Marti i Franques 1, E08028, Barcelona (Spain); Bolmont, J.; Corona, P. [LPNHE, Universite Paris VI and Universite Paris VII and IN2P3/CNRS, Barre 12-22, 1er etage, 4 place Jussieu, 75252 Paris (France); Feinstein, F. [LUPM, Universite Montpellier II and IN2P3/CNRS, CC072, bat. 13, place Eugene Bataillon, 34095 Montpellier (France); Glicenstein, J-F. [IRFU/DSM/CEA, CE-Saclay, Bat. 141 SEN Saclay, F-91191, Gif-sur-Yvette (France); Naumann, C.L.; Nayman, P. [LPNHE, Universite Paris VI and Universite Paris VII and IN2P3/CNRS, Barre 12-22, 1er etage, 4 place Jussieu, 75252 Paris (France); Ribo, M. [Dept. AM i Dept. ECM, Institut de Ciencies del Cosmos (ICC), Universitat de Barcelona. Marti i Franques 1, E08028, Barcelona (Spain); and others

    2012-12-11

    The NECTAr collaboration's FE option for the camera of the CTA is a 16 bits and 1-3 GS/s sampling chip based on analog memories including most of the readout functions. This works describes the input amplifiers of the NECTAr ASIC. A fully differential wideband amplifier, with voltage gain up to 20 V/V and a BW of 400 MHz. As it is impossible to design a fully differential OpAmp with an 8 GHz GBW product in a 0.35 CMOS technology, an alternative implementation based on HF linearized transconductors is explored. The output buffer is a class AB miller operational amplifier, with special non-linear current boost.

  11. The NectarCAM camera project

    CERN Document Server

    Glicenstein, J-F; Barrio, J-A; Blanch, O; Boix, J; Bolmont, J; Boutonnet, C; Cazaux, S; Chabanne, E; Champion, C; Chateau, F; Colonges, S; Corona, P; Couturier, S; Courty, B; Delagnes, E; Delgado, C; Ernenwein, J-P; Fegan, S; Ferreira, O; Fesquet, M; Fontaine, G; Fouque, N; Henault, F; Gascón, D; Herranz, D; Hermel, R; Hoffmann, D; Houles, J; Karkar, S; Khelifi, B; Knödlseder, J; Martinez, G; Lacombe, K; Lamanna, G; LeFlour, T; Lopez-Coto, R; Louis, F; Mathieu, A; Moulin, E; Nayman, P; Nunio, F; Olive, J-F; Panazol, J-L; Petrucci, P-O; Punch, M; Prast, J; Ramon, P; Riallot, M; Ribó, M; Rosier-Lees, S; Sanuy, A; Siero, J; Tavernet, J-P; Tejedor, L A; Toussenel, F; Vasileiadis, G; Voisin, V; Waegebert, V; Zurbach, C

    2013-01-01

    In the framework of the next generation of Cherenkov telescopes, the Cherenkov Telescope Array (CTA), NectarCAM is a camera designed for the medium size telescopes covering the central energy range of 100 GeV to 30 TeV. NectarCAM will be finely pixelated (~ 1800 pixels for a 8 degree field of view, FoV) in order to image atmospheric Cherenkov showers by measuring the charge deposited within a few nanoseconds time-window. It will have additional features like the capacity to record the full waveform with GHz sampling for every pixel and to measure event times with nanosecond accuracy. An array of a few tens of medium size telescopes, equipped with NectarCAMs, will achieve up to a factor of ten improvement in sensitivity over existing instruments in the energy range of 100 GeV to 10 TeV. The camera is made of roughly 250 independent read-out modules, each composed of seven photo-multipliers, with their associated high voltage base and control, a read-out board and a multi-service backplane board. The read-out b...

  12. Sugar Metabolism in Hummingbirds and Nectar Bats

    Directory of Open Access Journals (Sweden)

    Raul K. Suarez

    2017-07-01

    Full Text Available Hummingbirds and nectar bats coevolved with the plants they visit to feed on floral nectars rich in sugars. The extremely high metabolic costs imposed by small size and hovering flight in combination with reliance upon sugars as their main source of dietary calories resulted in convergent evolution of a suite of structural and functional traits. These allow high rates of aerobic energy metabolism in the flight muscles, fueled almost entirely by the oxidation of dietary sugars, during flight. High intestinal sucrase activities enable high rates of sucrose hydrolysis. Intestinal absorption of glucose and fructose occurs mainly through a paracellular pathway. In the fasted state, energy metabolism during flight relies on the oxidation of fat synthesized from previously-ingested sugar. During repeated bouts of hover-feeding, the enhanced digestive capacities, in combination with high capacities for sugar transport and oxidation in the flight muscles, allow the operation of the “sugar oxidation cascade”, the pathway by which dietary sugars are directly oxidized by flight muscles during exercise. It is suggested that the potentially harmful effects of nectar diets are prevented by locomotory exercise, just as in human hunter-gatherers who consume large quantities of honey.

  13. Estudios morfo-anatómicos en nectarios florales y extraflorales de Triumfetta rhomboidea (Malvaceae, Grewioideae Morpho-anatomical studies of the floral and extrafloral nectaries of Triumfetta rhomboidea (Malvaceae, Grewioideae

    Directory of Open Access Journals (Sweden)

    Elsa Lattar

    2009-07-01

    Full Text Available La morfo-anatomía de los nectarios florales y extraflorales tricomáticos de Triumfetta rhomboidea Jacq. se estudió con microscopio óptico y microscopio electrónico de barrido. Las cinco glándulas nectaríferas florales, están localizadas en el androginóforo, mientras que los nectarios extraflorales se hallan en los márgenes de la base de la lámina en la hoja y en los márgenes de la bráctea. Las diferencias observadas entre ellos están dadas por el tamaño y la forma de las células epidérmicas basales, el número de las células del pie y de la cabezuela de los tricomas glandulares, los idioblastos del parénquima secretor y el tejido vascular que inerva los nectarios. El análisis de la varianza mostró diferencias significativas entre los nectarios florales y extraflorales en las siguientes variables: longitud y diámetro de la cabezuela, longitud y ancho del pie, pared periclinal de la célula epidérmica basal. Estos resultados fueron congruentes con el análisis de componentes principales (ACP. La longitud de cabezuela y la pared periclinal de la célula basal permitieron reconocer los tres tipos de nectarios, mientras el diámetro de cabezuela y la longitud y ancho de pie sólo diferenciaron los nectarios florales de los extraflorales. Los resultados de este trabajo se discuten en relación a información previa sobre el género.The morpho-anatomy of the floral and extrafloral trichomatic nectaries of Triumfetta rhomboidea Jacq. was studied by light and scanning electron microscope. Five nectariferous glands are located on the androgynophore, whereas extrafloral nectaries are on the margins at the base of the leaf and on the margins of the bract. The differences observed between them are the size and shape of the epidermal basal cells, the number of the foot and the head cells of the glandular trichomes, the idioblasts of the secretor parenchyma and the vascular tissue which innervates the nectaries. The analysis of variance

  14. Nectar defense and hydrogen peroxide in floral nectar of Cucurbita pepo

    Directory of Open Access Journals (Sweden)

    Daniele Nocentini

    2015-03-01

    Full Text Available This study was carried out to investigate some similarities between the nectaries of Nicotiana sp. and Cucurbita pepo, such as starch accumulation in the nectary parenchyma, changes in nectary color during maturation, and the production of a large quantity of sucrose-dominant nectar. The concentration of hydrogen peroxide in C. pepo floral nectar was determined in order to verify the presence of a defense mechanism similar to that found in Nicotiana sp. which protects nectar from yeast and bacteria proliferation. We also tested the eventual accumulation of antioxidants in the nectary of C. pepo as a protection against oxidative stress caused by hydrogen peroxide. The level of hydrogen peroxide found in the floral nectar of C. pepo was much lower than that found in Nicotiana sp. and the male flowers of Cucurbita had a higher concentration than the female flowers. The low oxidative stress induced by this level of hydrogen peroxide caused the accumulation of a low amount of lutein inside the plastoglobules which were contained in amyloplasts. Plastids of the C. pepo nectary are specialized in the accumulation of starch rather than antioxidants.

  15. Nectar-living yeasts of a tropical host plant community: diversity and effects on community-wide floral nectar traits

    Directory of Open Access Journals (Sweden)

    Azucena Canto

    2017-07-01

    Full Text Available We characterize the diversity of nectar-living yeasts of a tropical host plant community at different hierarchical sampling levels, measure the associations between yeasts and nectariferous plants, and measure the effect of yeasts on nectar traits. Using a series of hierarchically nested sampling units, we extracted nectar from an assemblage of host plants that were representative of the diversity of life forms, flower shapes, and pollinator types in the tropical area of Yucatan, Mexico. Yeasts were isolated from single nectar samples; their DNA was identified, the yeast cell density was estimated, and the sugar composition and concentration of nectar were quantified using HPLC. In contrast to previous studies from temperate regions, the diversity of nectar-living yeasts in the plant community was characterized by a relatively high number of equally common species with low dominance. Analyses predict highly diverse nectar yeast communities in a relatively narrow range of tropical vegetation, suggesting that the diversity of yeasts will increase as the number of sampling units increases at the level of the species, genera, and botanical families of the hosts. Significant associations between specific yeast species and host plants were also detected; the interaction between yeasts and host plants impacted the effect of yeast cell density on nectar sugars. This study provides an overall picture of the diversity of nectar-living yeasts in tropical host plants and suggests that the key factor that affects the community-wide patterns of nectar traits is not nectar chemistry, but rather the type of yeasts interacting with host plants.

  16. Effects of nectar-robbing on plant reproduction and evolution

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yanwen; WANG Yong; GUO Youbao

    2007-01-01

    The relationship between plant and pollinator is considered as the mutualism because plant benefits from the pollinator's transport of male gametes and pollinator benefits from plant's reward.Nectar robbers are frequently described as cheaters in the plant-pollinator mutualism,because it is assumed that they obtain a reward (nectar) without providing a service (pollination).Nectar robbers are birds,insects,or other flower visitors that remove nectar from flowers through a hole pierced or bitten in the corolla.Nectar robbing represents a complex relationship between animals and plants.Whether plants benefit from the relationship is always a controversial issue in earlier studies.This paper is a review of the recent literatures on nectar robbing and attempts to acquire an expanded understanding of the ecological and evolutionary roles that robbers play.Understanding the effects of nectar robbers on the plants that they visited and other flower visitors is especially important when one considers the high rates of robbing that a plant population may experience and the high percentage of all flower visitors that nectar robbers make to some species.There are two standpoints in explaining why animals forage on flowers and steal nectar in an illegitimate behavior.One is that animals can only get food in illegitimate way because of the mismatch of the morphologies of animals'mouthparts and floral structure.The other point of view argues that nectar robbing is a relatively more efficient,thus more energy-saving way for animals to get nectar from flowers.This is probably associated with the difficulty of changing attitudes that have been held for a long time.In the case of positive effect,the bodies of nectar robbers frequently touch the sex organs of plants during their visiting to the flowers and causing pollination.The neutral effect,nectar robbers' behavior may destruct the corollas of flowers,but they neither touch the sex organs nor destroy the ovules.Their behavior

  17. Nectar feeding by the early-spring mosquito Aedes provocans.

    Science.gov (United States)

    Smith, S M; Gadawski, R M

    1994-07-01

    Nectar feeding by males and females of the mosquito Aedes provocans was studied at a site near Belleville, Ontario, Canada. Canada plum, Prunus nigra, and especially pin cherry, P. pensylvanica, bloomed contemporaneously with the emergence of Ae. provocans and were important nectar sources for adult mosquitoes during their first week of life. Blossoms of P. pensylvanica shielded for 24 h from foragers produced an average of 0.14 mg of sugar (approximately 2.3J). This nectar was avidly sought by both sexes of Ae. provocans; > 97% of the blossoms were visited by mosquitoes in the first few days of blooming. Young adult mosquitoes were found on blossoms at all hours of the day and night; feeding on P. nigra was strongly eocrepuscular, whereas on P. pensylvanica feeding was much less strongly periodic. Adults foraged for nectar in an energy-conserving, pedestrian strategy, devoting 56% (females) and 68% (males) of their time on blossoms to nectar feeding during foraging bouts that lasted a median of 5.3 min. Both sexes sought nectar soon after emergence--males before they had completed hypopygial rotation or swarmed, and females before mating or host seeking. Female Ae. provocans sought nectar in all stages of oogenesis, but primarily at the initiation of a gonotrophic cycle. Energy stores in the crop averaged 18J per female, with a distribution that depended on gonotrophic age and parity.

  18. Yeast identification in floral nectar of Mimulus aurantiacus (Invited)

    Science.gov (United States)

    Kyauk, C.; Belisle, M.; Fukami, T.

    2009-12-01

    Nectar is such a sugar-rich resource that serves as a natural habitat in which microbes thrive. As a result, yeasts arrive to nectar on the bodies of pollinators such as hummingbirds and bees. Yeasts use the sugar in nectar for their own needs when introduced. This research focuses on the identification of different types of yeast that are found in the nectar of Mimulus aurantiacus (commonly known as sticky monkey-flower). Unopened Mimulus aurantiacus flower buds were tagged at Jasper Ridge and bagged three days later. Floral nectar was then extracted and plated on potato dextrose agar. Colonies on the plates were isolated and DNA was extracted from each sample using QIAGEN DNeasy Plant Mini Kit. The DNA was amplified through PCR and ran through gel electrophoresis. The PCR product was used to clone the nectar samples into an E.coli vector. Finally, a phylogenetic tree was created by BLAST searching sequences in GenBank using the Internal Transcribed Space (ITS) locus. It was found that 18 of the 50 identified species were Candida magnifica, 14 was Candida rancensis, 6 were Crytococcus albidus and there were 3 or less of the following: Starmella bombicola, Candida floricola, Aureobasidium pullulans, Pichia kluyvera, Metschnikowa cibodaserisis, Rhodotorua colostri, and Malassezia globosa. The low diversity of the yeast could have been due to several factors: time of collection, demographics of Jasper Ridge, low variety of pollinators, and sugar concentration of the nectar. The results of this study serve as a necessary first step for a recently started research project on ecological interactions between plants, pollinators, and nectar-living yeast. More generally, this research studies the use of the nectar-living yeast community as a natural microcosm for addressing basic questions about the role of dispersal and competitive and facilitative interactions in ecological succession.

  19. 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.

  20. 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.

  1. Milieufactoren en beschikbaarheid nectar en stuifmeel in graslanden

    NARCIS (Netherlands)

    Ozinga, W.A.; Geerts, R.H.E.M.; Hennekens, S.M.; Schaminee, J.H.J.

    2016-01-01

    Plantengemeenschappen spelen bij veel ecosysteemfuncties en -diensten een cruciale rol. De bijdrage van plantensoorten hangt af van functionele eigenschappen als het aanbod van nectar en stuifmeel in bloemen. Lokale plantengemeenschappen verschillen sterk in het spectrum aan eigenschappen van de soo

  2. Climate change reduces nectar secretion in two common Mediterranean plants

    OpenAIRE

    Takkis, Krista; Tscheulin, Thomas; Tsalkatis, Panagiotis; Petanidou, Theodora

    2015-01-01

    Global warming can lead to considerable impacts on natural plant communities, potentially inducing changes in plant physiology and the quantity and quality of floral rewards, especially nectar. Changes in nectar production can in turn strongly affect plant–pollinator interaction networks—pollinators may potentially benefit under moderate warming conditions, but suffer as resources reduce in availability as elevated temperatures become more extreme. Here, we studied the effect of elevated temp...

  3. 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.

  4. The co-optimization of floral display and nectar reward

    Indian Academy of Sciences (India)

    Prajakta V Belsare; Balasubramanian Sriram; Milind G Watve

    2009-12-01

    In most insect-pollinated flowers, pollinators cannot detect the presence of nectar without entering the flower. Therefore, flowers may cheat by not producing nectar and may still get pollinated. Earlier studies supported this ‘cheater flower’ hypothesis and suggested that the cost saving by cheater flowers could be the most predominant selective force in the evolution of nectarless flowers. Previous models as well as empirical studies have addressed the problem of optimizing the proportion of nectarless and nectarful flowers. However, there has been no attempt to optimize the investment in nectar production along with that in floral display. One of the key questions that arises is whether the floral display will evolve to be an honest indicator of nectar reward. We use a mathematical model to cooptimize the investments in nectar and floral display in order to achieve maximum reproductive success. The model assumes that pollinators rely on a relative rather than an absolute judgement of reward. A conspicuous floral display attracts naïve pollinators on the one hand and enhances pollinator learning on the other. We show that under these assumptions, plant–pollinator co-evolution leads to honest signalling, i.e. a positive correlation between display and reward.

  5. Repellence and attraction of Apis mellifera foragers by nectar alkaloids

    Directory of Open Access Journals (Sweden)

    Hroncová Z.

    2016-03-01

    Full Text Available Plant secondary metabolites present naturally in nectar, such as alkaloids, may change the behavioural responses of floral visitors and affect pollination. Some studies have shown that nectar containing low concentrations of these secondary metabolites is preferred by honey bee foragers over pure nectar. However, it remains unclear whether this is caused by dependence or addictive behaviour, a simple taste preference, or by other conditions such as self-medication. In our choice experiment, free-flying bees were presented with artificial flowers holding 20% sucrose containing 0.5−50 μg ml−1 of one of the naturally occurring nectar alkaloids - caffeine, nicotine, senecionine, and gelsemine. Nectar uptake was determined by weighing each flower and comparing the weight to that of the control flower. Our experimental design minimized memorizing and marking; despite this, caffeine was significantly preferred at concentrations 0.5−2 μg ml−1 over control nectar; this preference was not observed for other alkaloids. All of the compounds tested were repellent at concentrations above 5 μg ml−1. We confirmed previous reports that bees exhibit a preference for caffeine, and hypothesize that this is not due only to addictive behaviour but is at least partially mediated by taste preference. We observed no significant preference for nicotine or any other alkaloid.

  6. Honeybees prefer warmer nectar and less viscous nectar, regardless of sugar concentration

    OpenAIRE

    Nicolson, Susan W.; de Veer, Leo; Köhler, Angela; Pirk, Christian W.W.

    2013-01-01

    The internal temperature of flowers may be higher than air temperature, and warmer nectar could offer energetic advantages for honeybee thermoregulation, as well as being easier to drink owing to its lower viscosity. We investigated the responses of Apis mellifera scutellata (10 colonies) to warmed 10% w/w sucrose solutions, maintained at 20–35°C, independent of low air temperatures, and to 20% w/w sucrose solutions with the viscosity increased by the addition of the inert polysaccharide Tylo...

  7. Climate change reduces nectar secretion in two common Mediterranean plants.

    Science.gov (United States)

    Takkis, Krista; Tscheulin, Thomas; Tsalkatis, Panagiotis; Petanidou, Theodora

    2015-09-15

    Global warming can lead to considerable impacts on natural plant communities, potentially inducing changes in plant physiology and the quantity and quality of floral rewards, especially nectar. Changes in nectar production can in turn strongly affect plant-pollinator interaction networks-pollinators may potentially benefit under moderate warming conditions, but suffer as resources reduce in availability as elevated temperatures become more extreme. Here, we studied the effect of elevated temperatures on nectar secretion of two Mediterranean Lamiaceae species-Ballota acetabulosa and Teucrium divaricatum. We measured nectar production (viz. volume per flower, sugar concentration per flower and sugar content per flower and per plant), number of open and empty flowers per plant, as well as biomass per flower under a range of temperatures selected ad hoc in a fully controlled climate chamber and under natural conditions outdoors. The average temperature in the climate chamber was increased every 3 days in 3 °C increments from 17.5 to 38.5 °C. Both study species showed a unimodal response of nectar production (volume per flower, sugar content per flower and per plant) to temperature. Optimal temperature for sugar content per flower was 25-26 °C for B. acetabulosa and 29-33 °C for T. divaricatum. According to our results, moderate climate warming predicted for the next few decades could benefit nectar secretion in T. divaricatum as long as the plants are not water stressed, but have a moderate negative effect on B. acetabulosa. Nevertheless, strong warming as predicted by climate change models for the end of the 21st century is expected to reduce nectar secretion in both species and can thus significantly reduce available resources for both wild bees and honeybees in Mediterranean systems. Published by Oxford University Press on behalf of the Annals of Botany Company.

  8. Sugar gustatory thresholds and sugar selection in two species of Neotropical nectar-eating bats.

    Science.gov (United States)

    Ayala-Berdon, Jorge; Rodríguez-Peña, Nelly; García Leal, Cristian; Stoner, Kathryn E; Schondube, Jorge E

    2013-02-01

    Nectar-feeding bats play an important role in natural communities acting as pollinators; however, the characteristics that affect their food selection are unclear. Here we explore the role that sugar gustatory thresholds and sugar concentration play on sugar selection of Glossophaga soricina and Leptonycteris yerbabuenae. We offered bats paired feeders containing sugar solutions of sucrose (S), glucose (G) or fructose (F) vs. pure water, and sucrose vs. 1:1 equicaloric solutions of glucose-fructose at 5, 15 and 35% (wt./vol.). To see the effect of sweetness on sugar selection, we habituated the bats with a diet containing either sucrose or hexoses and subsequently evaluated sugar preferences. Sugar thresholds were Ssugar preferences when the bats fed on dilute nectars. L. yerbabuenae changed its sugar preferences with concentration while G. soricina did not. Finally, the bats consistently preferred the sugar they were habituated to. Our results suggest that bats become accustomed to the sugar found in the most abundant plants they use, and thus prefer the most common sugars included in their diet. This could confer an advantage by allowing them shifting sugar preferences on the most common food present in their environment.

  9. Seasonal amounts of nutrients in Western cherry fruit fly (Diptera: Tephritidae) and their relation to nutrient availability on cherry plant surfaces.

    Science.gov (United States)

    Yee, Wee L; Chapman, Peter S

    2008-10-01

    Relatively little is known about the nutritional ecology of fruit flies in the genus Rhagoletis. In this study, nutrient amounts in male and female western cherry fruit fly, Rhagoletis indifferens Curran, and availability of nitrogen and sugar on surfaces of leaves, fruit, and extrafloral nectaries (EFNs) of sweet cherry trees, were determined from late May to late June 2005 and of sugar from EFNs from mid-May to late June 2007 in Washington state. Protein amounts in male and female flies did not differ over the season. Nitrogen was present on leaves, fruit, and EFNs during the sampling period, but amounts on leaves and fruit were lower in late May than the rest of the season. Sugar amounts in flies did not differ over the season. Sugar was present on leaf, fruit, and EFN surfaces all season, but amounts on all three were lower in late May than later in the season. Fructose and glucose were the predominant sugars on all plant surfaces, but sucrose was also present in nectar from EFNs. In outdoor and field cage experiments in 2004 and 2006, more flies survived when cherry branches with leaves and fruit were present than absent. Results suggest that R. indifferens maintains stable protein and sugar levels throughout the season because sufficient amounts of nutrients are found in cherry trees during this time and that increases in nutrient availability caused by ripening and damaged cherries later in the season do not result in increased amounts of nutrients in flies.

  10. Specialist nectar-yeasts decline with urbanization in Berlin

    Science.gov (United States)

    Wehner, Jeannine; Mittelbach, Moritz; Rillig, Matthias C.; Verbruggen, Erik

    2017-01-01

    Nectar yeasts are common inhabitants of insect-pollinated flowers but factors determining their distribution are not well understood. We studied the influence of host identity, environmental factors related to pollution/urbanization, and the distance to a target beehive on local distribution of nectar yeasts within Robinia pseudoacacia L. and Tilia tomentosa Moench in Berlin, Germany. Nectar samples of six individuals per species were collected at seven sites in a 2 km radius from each target beehive and plated on YM-Agar to visualise the different morphotypes, which were then identified by sequencing a section of the 26S rDNA gene. Multivariate linear models were used to analyze the effects of all investigated factors on yeast occurrence per tree. Yeast distribution was mainly driven by host identity. The influence of the environmental factors (NO2, height of construction, soil sealing) strongly depended on the radius around the tree, similar to the distance of the sampled beehive. Incidence of specialist nectar-borne yeast species decreased with increasing pollution/urbanization index. Given that specialist yeast species gave way to generalist yeasts that have a reduced dependency on pollinators for between-flower dispersal, our results indicate that increased urbanization may restrict the movement of nectar-specialized yeasts, via limitations of pollinator foraging behavior. PMID:28358006

  11. Nectar production in species of the Genus galanthus L. (Amaryllidaceae from Serbia

    Directory of Open Access Journals (Sweden)

    Jovanović Filip

    2014-01-01

    Full Text Available As a contribution to the study of the melliferous flora of Serbia, nectar production in two species of the genus Galanthus L. (G. nivalis L., and G. elwesii Hook. was investigated. The intensity of nectar secretion was determined directly, using the microcapillary method. The study included determination of the total daily nectar amount per flower, and an analysis of nectar secretion dynamics during the day and during the flower ontogeny. The results show that the total daily amount of nectar per flower is low, and flowers of both species exude nectar only once during the day and during the flower ontogeny. However, despite the low nectar production, Galanthus species represent a first valuable source of nectar and pollen to pollinators in the early spring period, when only a small number of species are in the flowering phenophase.

  12. 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...

  13. An ants-eye view of an ant-plant protection mutualism

    Science.gov (United States)

    Lanan, M. C.; Bronstein, J. L.

    2013-01-01

    Ant protection of extrafloral nectar-secreting plants (EFN plants) is a common form of mutualism found in most habitats around the world. However, very few studies have considered these mutualisms from the ant, rather than the plant, perspective. In particular, a whole-colony perspective that takes into account the spatial structure and nest arrangement of the ant colonies that visit these plants has been lacking, obscuring when and how colony-level foraging decisions might affect tending rates on individual plants. Here, we experimentally demonstrate that recruitment of Crematogaster opuntiae (Buren) ant workers to the extrafloral nectar-secreting cactus Ferocactus wislizeni (Englem) is not independent between plants up to 5m apart. Colony territories of C. opuntiae are large, covering areas of up to 5000m2, and workers visit between five and thirty-four extrafloral nectar-secreting barrel cacti within the territories. These ants are highly polydomous, with up to twenty nest entrances dispersed throughout the territory and interconnected by trail networks. Our study demonstrates that worker recruitment is not independent within large polydomous ant colonies, highlighting the importance of considering colonies rather than individual workers as the relevant study unit within ant/plant protection mutualisms PMID:23515612

  14. NEC1, a regulator of nectary development and nectar production in Petunia hybrida

    NARCIS (Netherlands)

    Ge, Ya-Xin

    2001-01-01

    This thesis describes an efficient cloning, characterization and functional analysis of a nectary-specific gene in Petunia hybrida. NEC1, a novel gene, is highly expressed in nectaries. NEC1 is involved in nectar production and nectar secretion. Nectar secreted from floral nectaries is the main flor

  15. Air pollution impedes plant-to-plant communication by volatiles.

    Science.gov (United States)

    Blande, James D; Holopainen, Jarmo K; Li, Tao

    2010-09-01

    Volatile organic compounds (VOCs) emitted by damaged plants convey information to undamaged neighbouring plants, and previous research has shown that these signals are effective over short distances in nature. Many herbivore-induced VOCs react with ozone, which is the most important tropospheric air pollutant in rural areas. We used extrafloral nectar (EFN) secretion as a phenotypic indicator of between-plant communication in Phaseolus lunatus L. (Lima bean) and show that an ozone-rich (80 ppb) atmosphere reduces the distance over which signalling occurs. We found that ozone degrades several herbivore-induced VOCs, a likely mechanism reducing communication distances. Direct exposure to 80-ppb ozone did not affect the VOC emissions from P. lunatus. In addition, we demonstrated that high ozone concentrations, 120 and 160 ppb, induced EFN secretion in exposed plants, whereas more moderate concentrations, 80 and 100 ppb, did not. This suggests that ozone can play a complex role in the indirect defence of P. lunatus.

  16. EFNS偏头痛药物治疗指南EFNS特别工作组的报告%EFNS Guideline on the Drug Treatment of Migraine Report of an EFNS Task Force

    Institute of Scientific and Technical Information of China (English)

    S.Evers; 吴宣富; J.(A)fra; A.Frese; P.J.Goadsby; M.Linde; A.May; P.S.Sándor; 张现伟; 张敏

    2007-01-01

    偏头痛是最常见的功能障碍性神经疾病之一,会对患者的生活质量造成严重影响.为了在文献检索和专家组共识基础上对不同类型偏头痛综合征的各种药物治疗方案提供循证或专家推荐,我们从现有的所有医学参考文献系统中筛选出关于有先兆型或无先兆型偏头痛以及偏头痛样综合征等各种类型临床资料进行分析.根据欧洲神经病学学会联盟(European Federation of Neurological Societies,EFNS)制定的推荐意见分级方案对这些研究结果进行评价从而确定A级、B级或C级推荐和良好的临床实践要点.对于偏头痛急性发作期的治疗,推荐口服非甾体消炎药(NSAID)和曲坦类药物.用药方案应遵循分层治疗的观念.在服用NSAID和曲坦类药物之前,推荐口服甲氧氯普胺或多潘立酮.极重度发作的首选药物为静脉注射乙酰水杨酸或皮下注射舒马曲坦.偏头痛持续状态或许可用类固醇治疗.对于偏头痛的预防性治疗,β-受体阻断药(普萘洛尔和美托洛尔)、氟桂利嗪、丙戊酸和托吡酯可作为首选用药,其次可选择阿米替林、萘普生、蜂斗菜烯碱和比索洛尔.

  17. EFNS guideline on the drug treatment of migraine-revised report of an EFNS taskforce%EFNS偏头痛药物治疗指南EFNS特别工作组修订报告

    Institute of Scientific and Technical Information of China (English)

    S.Evers; 侯书伟; J.(A)fra; A Frese; P.J.Goadsby; M.Linde; A.May; P.S.sándor; 吴宏赟; 胡志强

    2010-01-01

    背景 偏头痛是最常见的失能性神经疾病之一,会严重损害患者的生活质量.目的 在文献检索和专家共识的基础上,对特殊类型偏头痛综合征的各种药物治疗方案提供循证或专家推荐.方法 从现有的所有医学参考文献系统中筛选出关于有先兆型或无先兆型偏头痛以及偏头痛样综合征的各种类型临床资料进行分析.根据欧洲神经病学学会联盟(European Federation of Neurological Societies,EFNS)制定的推荐意见分级方案对这些研究结果进行评价,从而确定A级、B级或C级推荐和良好的临床实践要点.推荐意见 推荐口服非甾体消炎药(non-steroidal anti-inflammatory drug,NSAID)和曲坦类药物用于偏头痛发作的急性期治疗.用药方案应遵循分层治疗观念.在口服NSAID和曲坦类药物之前,推荐口服甲氧氯普胺或多潘立酮.在极重度偏头痛发作时,首选静脉注射乙酸水杨酸或皮下注射舒马曲坦.偏头痛持续状态可用类固醇治疗,虽然并非总是有效;也可用二氢麦角胺治疗.β-受体阻滞药(普萘洛尔和美托洛尔)、氟桂利嗪、丙戊酸和托吡酯可作为偏头痛预防性治疗的首选用药,其次可选用阿米替林、萘普生、蜂斗菜烯碱和比索洛尔.

  18. Stimulation of flower nectar replenishment by removal: A survey of eleven animal-pollinated plant species

    Directory of Open Access Journals (Sweden)

    Elaine Y Luo

    2014-02-01

    Full Text Available Understanding the interaction between reward-seeking flower feeding animals and plants requires consideration of the dynamic nature of nectar secretion. Studies on several plants suggest that nectar secretion may increase in response to its removal, but it is not clear whether the phenomenon is widespread. We determined whether 11 species of Colorado mountain wildflowers showed removal-enhanced nectar replenishment (RENR. We measured floral phenology, nectar volumes, rate of replenishment, and compared the cumulative nectar produced following five hourly removals with that accumulated after five hours. Nectar replenishment occurred rapidly, within minutes; statistically significant RENR was observed in 9 of our 11 study species, with the strongest effects in bee-pollinated species. We discuss the implications of RENR in plant species on the measurement of nectar, the adaptive advantage of RENR, and the energetic costs of RENR.

  19. Nectar Theft and Floral Ant-Repellence: A Link between Nectar Volume and Ant-Repellent Traits?

    Science.gov (United States)

    Ballantyne, Gavin; Willmer, Pat

    2012-01-01

    As flower visitors, ants rarely benefit a plant. They are poor pollinators, and can also disrupt pollination by deterring other flower visitors, or by stealing nectar. Some plant species therefore possess floral ant-repelling traits. But why do particular species have such traits when others do not? In a dry forest in Costa Rica, of 49 plant species around a third were ant-repellent at very close proximity to a common generalist ant species, usually via repellent pollen. Repellence was positively correlated with the presence of large nectar volumes. Repellent traits affected ant species differently, some influencing the behaviour of just a few species and others producing more generalised ant-repellence. Our results suggest that ant-repellent floral traits may often not be pleiotropic, but instead could have been selected for as a defence against ant thieves in plant species that invest in large volumes of nectar. This conclusion highlights to the importance of research into the cost of nectar production in future studies into ant-flower interactions. PMID:22952793

  20. Hummingbird responses to gender-biased nectar production: are nectar biases maintained by natural or sexual selection?

    Science.gov (United States)

    Carlson, Jane E

    2008-01-01

    Pollinators mediate the evolution of secondary floral traits through both natural and sexual selection. Gender-biased nectar, for example, could be maintained by one or both, depending on the interactions between plants and pollinators. Here, I investigate pollinator responses to gender-biased nectar using the dichogamous herb Chrysothemis friedrichsthaliana (Gesneriaceae) which produces more nectar during the male floral phase. Previous research showed that the hummingbird pollinator Phaethornis striigularis visited male-phase flowers more often than female-phase flowers, and multiple visits benefited male more than female fecundity. If sexual selection maintains male-biased rewards, hummingbirds should prefer more-rewarding flowers independent of floral gender. If, however, differential rewards are partially maintained through natural selection, hummingbirds should respond to asymmetry with visits that reduce geitonogamy, i.e. selfing and pollen discounting. In plants with male biases, these visit types include single-flower visits and movements from low to high rewards. To test these predictions, I manipulated nectar asymmetry between pairs of real or artificial flowers on plants and recorded foraging behaviour. I also assessed maternal costs of selfing using hand pollinations. For plants with real flowers, hummingbirds preferred more-rewarding flowers and male-phase morphology, the latter possibly owing to previous experience. At artificial arrays, hummingbirds responded to extreme reward asymmetry with increased single-flower visits; however, they moved from high to low rewards more often than low to high. Finally, selfed flowers did not produce inferior seeds. In summary, sexual selection, more so than geitonogamy avoidance, maintains nectar biases in C. friedrichsthaliana, in one of the clearest examples of sexual selection in plants, to date. PMID:18460431

  1. Intraspecific variability of floral nectar volume and composition in rapeseed (Brassica napus L. var. oleifera

    Directory of Open Access Journals (Sweden)

    Michele eBertazzini

    2016-03-01

    Full Text Available Numerous angiosperms rely on pollinators to ensure efficient flower fertilization, offering a reward consisting of nourishing nectars produced by specialized floral cells, known as nectaries. Nectar components are believed to derive from phloem sap that is enzymatically processed and transformed within nectaries. An increasing body of evidence suggests that nectar composition, mainly amino acids, may influence pollinator attraction and fidelity. This notwithstanding, little is known about the range of natural variability in nectar content for crop species. Sugar and amino acid composition of nectar harvested from field-grown plants at the 63 to 65 phenological stage was determined for a set of 44 winter genotypes of rapeseed, a bee-pollinated crop. Significant differences were found for solute concentrations, and an even higher variability was evident for nectar volumes, resulting in striking differences when results were expressed on a single flower basis. The comparison of nectar and phloem sap from a subset of 8 varieties pointed out qualitative and quantitative diversities with respect to both sugars and amino acids. Notably, amino acid concentration in phloem sap was up to one hundred times higher than in nectar. Phloem sap showed a much more uniform composition, suggesting that nectar variability depends mainly on nectary metabolism. A better understanding of the basis of nectar production would allow an improvement of seed set efficiency, as well as hive management and honey production.

  2. Nectar sugars and bird visitation define a floral niche for basidiomycetous yeast on the Canary Islands.

    Science.gov (United States)

    Mittelbach, Moritz; Yurkov, Andrey M; Nocentini, Daniele; Nepi, Massimo; Weigend, Maximilian; Begerow, Dominik

    2015-02-01

    Studies on the diversity of yeasts in floral nectar were first carried out in the late 19th century. A narrow group of fermenting, osmophilous ascomycetes were regarded as exclusive specialists able to populate this unique and species poor environment. More recently, it became apparent that microorganisms might play an important role in the process of plant pollination. Despite the importance of these nectar dwelling yeasts, knowledge of the factors that drive their diversity and species composition is scarce. In this study, we linked the frequencies of yeast species in floral nectars from various host plants on the Canary Islands to nectar traits and flower visitors. We estimated the structuring impact of pollination syndromes (nectar volume, sugar concentration and sugar composition) on yeast diversity.The observed total yeast diversity was consistent with former studies, however, the present survey yielded additional basidiomycetous yeasts in unexpectedly high numbers. Our results show these basidiomycetes are significantly associated with ornithophilous flowers. Specialized ascomycetes inhabit sucrose-dominant nectars, but are surprisingly rare in nectar dominated by monosaccharides. There are two conclusions from this study: (i) a shift of floral visitors towards ornithophily alters the likelihood of yeast inoculation in flowers, and (ii) low concentrated hexose-dominant nectar promotes colonization of flowers by basidiomycetes. In the studied floral system, basidiomycete yeasts are acknowledged as regular members of nectar. This challenges the current understanding that nectar is an ecological niche solely occupied by ascomycetous yeasts.

  3. Invisible floral larcenies: microbial communities degrade floral nectar of bumble bee-pollinated plants.

    Science.gov (United States)

    Herrera, Carlos M; García, Isabel M; Pérez, Ricardo

    2008-09-01

    The ecology of nectarivorous microbial communities remains virtually unknown, which precludes elucidating whether these organisms play some role in plant-pollinator mutualisms beyond minor commensalism. We simultaneously assessed microbial abundance and nectar composition at the individual nectary level in flowers of three southern Spanish bumble bee-pollinated plants (Helleborus foetidus, Aquilegia vulgaris, and Aquilegia pyrenaica cazorlensis). Yeasts were frequent and abundant in nectar of all species, and variation in yeast density was correlated with drastic changes in nectar sugar concentration and composition. Yeast communities built up in nectar from early to late floral stages, at which time all nectaries contained yeasts, often at densities between 10(4) and 10(5) cells/mm3. Total sugar concentration and percentage sucrose declined, and percentage fructose increased, with increasing density of yeast cells in nectar. Among-nectary variation in microbial density accounted for 65% (H. foetidus and A. vulgaris) and 35% (A. p. cazorlensis) of intraspecific variance in nectar sugar composition, and 60% (H. foetidus) and 38% (A. vulgaris) of variance in nectar concentration. Our results provide compelling evidence that nectar microbial communities can have detrimental effects on plants and/or pollinators via extensive nectar degradation and also call for a more careful interpretation of nectar traits in the future, if uncontrolled for yeasts.

  4. Microorganisms transported by ants induce changes in floral nectar composition of an ant-pollinated plant.

    Science.gov (United States)

    de Vega, Clara; Herrera, Carlos M

    2013-04-01

    Interactions between plants and ants abound in nature and have significant consequences for ecosystem functioning. Recently, it has been suggested that nectar-foraging ants transport microorganisms to flowers; more specifically, they transport yeasts, which can potentially consume sugars and alter nectar composition. Therefore, ants could indirectly change nectar sugar profile, an important floral feature involved in the plant-pollinator mutualism. But this novel role for ants has never been tested. We here investigate the effects of nectarivorous ants and their associated yeasts on the floral nectar sugar composition of an ant-pollinated plant. Differences in the nectar sugar composition of ant-excluded and ant-visited flowers were examined in 278 samples by using high-performance liquid-chromatography. The importance of the genetic identity and density of ant-transported basidiomycetous and ascomycetous yeasts on the variation of nectar traits was also evaluated. Ant visitation had significant effects on nectar sugar composition. The nectar of ant-visited flowers contained significantly more fructose, more glucose, and less sucrose than the nectar of ant-excluded flowers, but these effects were context dependent. Nectar changes were correlated with the density of yeast cells in nectar. The magnitude of the effects of ant-transported ascomycetes was much higher than that of basiodiomycetes. Ants and their associated yeasts induce changes in nectar sugar traits, reducing the chemical control of the plant over this important floral trait. The potential relevance of this new role for ants as indirect nectar modifiers is a rich topic for future research into the ecology of ant-flower interactions.

  5. Why be a honeyless honey mesquite? Reproduction and mating system of nectarful and nectarless individuals.

    Science.gov (United States)

    Golubov, J; Eguiarte, L E; Mandujano, M C; López-Portillo, J; Montaña, C

    1999-07-01

    Populations of Prosopis glandulosa var. torreyana in the Chihuahuan desert have a fixed dimorphic system of nectar production in which half the individuals produce nectar (are nectarful) and the other half are nectarless. We analyzed the impact of nectar production on different estimates of fitness, comparing nectarful against nectarless individuals in size, mating system, seed traits, and fruit set in a 1-ha scrubland. Of the reproductive individuals (358), 46% were nectarful and 54% were nectarless. Neither tree size nor flowering phenology differed between nectar morphs. Fixation indices (F) for both progeny (F = -0.2) and adults (F = -0.45) were negative, and high heterozygosities were found in adults and progeny (H = 0.45). No differences were found between nectar morphs for F, H, and single (t(s) = 1.1) and multilocus (t(m) = 1.03) outcrossing rates. Controlled pollinations showed differences between selfing and control treatments with no differences between nectar morphs. Nectarless individuals produced significantly more pollen grains than did nectar producers, but all other measured floral traits showed no differences. Nectarful trees were visited by pollinators 21 times more often and had a significantly higher overall fruit set than did nectarless trees. No differences between nectar morphs in seed mass or in percentage seed germination were found, but heavier seeds tended to have higher heterozygosities. Both morphs had similar success as females, but nectarless trees had ∼7% higher male function. We discuss three possible scenarios for the evolution of the fixed dimorphism in nectar production, two involving unstable phases (substitution of one morph by the other, and evolution towards dioecy) and one stable scenario (maintenance of the dimorphic system).

  6. Real-time radiography at the NECTAR facility

    Energy Technology Data Exchange (ETDEWEB)

    Buecherl, T., E-mail: thomas.buecherl@radiochemie.de [Lehrstuhl fuer Radiochemie (RCM), Technische Universitaet Muenchen (TUM), Walther-Meissner-Str. 3, 85748 Garching (Germany); Lierse von Gostomski, Ch. [Lehrstuhl fuer Radiochemie (RCM), Technische Universitaet Muenchen (TUM), Walther-Meissner-Str. 3, 85748 Garching (Germany)

    2011-09-21

    A feasibility study has shown that real-time radiography using fission neutrons is possible at the NECTAR facility, when using an improved detection system for fast variations (Buecherl et al., 2009 ). Continuing this study, real-time measurements of slowly varying processes like the water uptake in medium sized trunks (diameter about 12 cm) and of slow periodic processes (e.g. a slowly rotating iron disk) are investigated successfully using the existing detection system.

  7. Chronic intake of fermented floral nectar by wild treeshrews

    OpenAIRE

    Wiens, Frank; Zitzmann, Annette; Lachance, Marc-André; Yegles, Michel; Pragst, Fritz; Wurst, Friedrich M.; von Holst, Dietrich; Guan, Saw Leng; Spanagel, Rainer

    2008-01-01

    For humans alcohol consumption often has devastating consequences. Wild mammals may also be behaviorally and physiologically challenged by alcohol in their food. Here, we provide a detailed account of chronic alcohol intake by mammals as part of a coevolved relationship with a plant. We discovered that seven mammalian species in a West Malaysian rainforest consume alcoholic nectar daily from flower buds of the bertam palm (Eugeissona tristis), which they pollinate. The 3.8% maximum alcohol co...

  8. Pseudomyrmex ants and Acacia host plants join efforts to protect their mutualism from microbial threats.

    Science.gov (United States)

    González-Teuber, Marcia; Heil, Martin

    2010-07-01

    Plants express numerous 'pathogenesis-related' (PR) proteins to defend themselves against pathogen infection. We recently discovered that PR-proteins such as chitinases, glucanases, peroxidases and thaumatin-like proteins are also functioning in the protection of extrafloral nectar (EFN) of Mexican Acacia myrmecophytes. These plants produce EFN, cellular food bodies and nesting space to house defending ant species of the genus Pseudomyrmex. More than 50 PR-proteins were discovered in this EFN and bioassays demonstrated that they actively can inhibit the growth of fungi and other phytopathogens. Although the plants can, thus, express PR-proteins and secrete them into the nectar, the leaves of these plants exhibit reduced activities of chitinases as compared to non-myrmecophytic plants and their antimicrobial protection depends on the mutualistic ants. When we deprived plants of their resident ants we observed higher microbial loads in the leaves and even in the tissue of the nectaries, as compared to plants that were inhabited by ants. The indirect defence that is achieved through an ant-plant mutualism can protect plants also from infections. Future studies will have to investigate the chemical nature of this mechanism in order to understand why plants depend on ants for their antimicrobial defence.

  9. Nectar Attracts Foraging Honey Bees with Components of Their Queen Pheromones.

    Science.gov (United States)

    Liu, Fanglin; Gao, Jie; Di, Nayan; Adler, Lynn S

    2015-11-01

    Floral nectar often contains chemicals that are deterrent to pollinators, presenting potential challenges to outcrossing plant species. Plants may be able to co-opt pollinator chemical signals to mitigate the negative effects of nectar deterrent compounds on pollination services. We found that buckwheat (Fagopyrum esculentum) and Mexican sunflower (Tithonia diversifolia) produce nectar with abundant phenolics, including three components of the Apis honeybee queen mandibular pheromone (QMP). In addition, these nectars contain a non-pheromonal phenolic, chlorogenic acid (CA), which was toxic to honeybees, and T. diversifolia nectar also contained isochlorogenic acid (IA). Fresh nectar or solutions containing nectar phenolics reduced Apis individual feeding compared to sucrose solutions. However, freely foraging bees preferred solutions with QMP components to control solutions, and QMP components over-rode or reversed avoidance of CA and IA. Furthermore, prior exposure to the presence or just the odor of QMP components removed the deterrent effects of CA and IA. By mimicking the honey bee pheromone blend, nectar may maintain pollinator attraction in spite of deterrent nectar compounds.

  10. Investigating the pollination syndrome of the Hawaiian lobeliad genus Clermontia (Campanulaceae) using floral nectar traits.

    Science.gov (United States)

    Pender, Richard J; Morden, Clifford W; Paull, Robert E

    2014-01-01

    Floral nectar sugar compositions have, for several decades, been used to predict a plant species' pollinator guild. Plants possessing a generalist ornithophilous pollination syndrome produce nectar that is dilute (8-12% w/v sugars) with a low sucrose to hexose (glucose and fructose) ratio. The Hawaiian lobeliad genus Clermontia contains 22 endemic species of shrubs and small trees that are believed to have evolved flowers adapted for pollination by now mostly extinct or endangered endemic passerines in the Drepanidinae and Mohoidae. We analyzed the nectar sugar compositions, concentration, and nectar standing crop of 23 taxa to test the assumption that Clermontia taxa have evolved floral traits in response to selection pressures from these avian pollinators. All Clermontia taxa produced nectar with sugar concentrations (mean: 9.2% w/v ± 1.8 SD) comparable to the nectar of other plant species with a generalized bird pollination system. Nectar sugars were overwhelmingly composed of hexoses in all taxa (mean sucrose/hexose ratio: 0.02 ± 0.02). Nectar standing crop volumes varied widely among taxa, ranging from 9.7 µL ± 7.1 to 430.5 µL ± 401.8 (mean volume: 177.8 ± 112.0). Collectively, the nectar traits indicate that Clermontia species possess a generalist passerine pollination syndrome.

  11. Nectar sugar composition of European Caryophylloideae (Caryophyllaceae) in relation to flower length, pollination biology and phylogeny.

    Science.gov (United States)

    Witt, T; Jürgens, A; Gottsberger, G

    2013-10-01

    Floral nectar composition has been explained as an adaptation to factors that are either directly or indirectly related to pollinator attraction. However, it is often unclear whether the sugar composition is a direct adaptation to pollinator preferences. Firstly, the lower osmolality of sucrose solutions means that they evaporate more rapidly than hexose solutions, which might be one reason why sucrose-rich nectar is typically found in flowers with long tubes (adapted to long-tongued pollinators), where it is better protected from evaporation than in open or short-tubed flowers. Secondly, it can be assumed that temperature-dependent evaporation is generally lower during the night than during the day so that selection pressure to secrete nectar with high osmolality (i.e. hexose-rich solutions) is relaxed for night-active flowers pollinated at night. Thirdly, the breeding system may affect selection pressure on nectar traits; that is, for pollinator-independent, self-pollinated plants, a lower selective pressure on nectar traits can be assumed, leading to a higher variability of nectar sugar composition independent of pollinator preferences, nectar accessibility and nectar protection. To analyse the relations between flower tube length, day vs. night pollination and self-pollination, the nectar sugar composition was investigated in 78 European Caryophylloideae (Caryophyllaceae) with different pollination modes (diurnal, nocturnal, self-pollination) using high-performance liquid chromatography (HPLC). All Caryophylleae species (Dianthus and relatives) were found to have nectar with more than 50% sucrose, whereas the sugar composition of Sileneae species (Silene and relatives) ranged from 0% to 98.2%. In the genus Silene, a clear dichotomous distribution of sucrose- and hexose-dominant nectars is evident. We found a positive correlation between the flower tube length and sucrose content in Caryophylloideae, particularly in day-flowering species, using both conventional

  12. Tongue Pressure Modulation during Swallowing: Water versus Nectar-Thick Liquids

    Science.gov (United States)

    Steele, Catriona M.; Bailey, Gemma L.; Molfenter, Sonja M.

    2010-01-01

    Purpose: Evidence of tongue-palate pressure modulation during swallowing between thin and nectar-thick liquids stimuli has been equivocal. This mirrors a lack of clear evidence in the literature of tongue and hyoid movement modulation between nectar-thick and thin liquid swallows. In the current investigation, the authors sought to confirm whether…

  13. Protein and alkaloid patterns of the floral nectar in some solanaceous species.

    Science.gov (United States)

    Kerchner, András; Darók, Judit; Bacskay, Ivett; Felinger, Attila; Jakab, Gábor; Farkas, Ágnes

    2015-09-01

    The family Solanaceae includes several melliferous plants, which tend to produce copious amounts of nectar. Floral nectar is a chemically complex aqueous solution, dominated by sugars, but minor components such as amino acids, proteins, flavonoids and alkaloids are present as well. This study aimed at analysing the protein and alkaloid profile of the nectar in seven solanaceous species. Proteins were examined with SDS-PAGE and alkaloids were analyzed with HPLC. The investigation of protein profile revealed significant differences in nectar-protein patterns not only between different plant genera, but also between the three Nicotiana species investigated. SDS-PAGE suggested the presence of several Nectarin proteins with antimicrobial activity in Nicotiana species. The nectar of all tobacco species contained the alkaloid nicotine, N. tabacum having the highest nicotine content. The nectar of Brugmansia suaveolens, Datura stramonium, Hyoscyamus niger and Lycium barbarum contained scopolamine, the highest content of which was measured in B. suaveolens. The alkaloid concentrations in the nectars of most solanaceous species investigated can cause deterrence in honeybees, and the nectar of N. rustica and N. tabacum can be considered toxic for honeybees.

  14. Pollinator foraging modifies nectar sugar composition in Helleborus foetidus (Ranunculaceae):An experimental test.

    Science.gov (United States)

    Canto, Azucena; Herrera, Carlos M; Medrano, Mónica; Pérez, Ricardo; García, Isabel M

    2008-03-01

    We experimentally tested the hypothesis that the extensive within-plant variation of nectar sugar composition in Helleborus foetidus (Ranunculaceae) and other species results from differences between flowers and nectaries in pollinator visitation history. Experiments were conducted to mimic single-nectary visits by wild-caught individuals of the main bee pollinators of H. foetidus, which were assayed for their capacity to modify the sugar composition of natural and artificial nectar. Experimental nectar probing with bee mouthparts induced extensive changes in proportional sugar composition 48 h after treatment, and bee taxa differed widely in their effects. Nectar probing by Andrena, medium-sized Anthophoridae, Apis mellifera, and Lasioglossum had no subsequent effects on nectar sugar composition, while probing by Bombus terrestris and B. pratorum induced an extensive reduction in percentage sucrose, a marked increase in percentage fructose, and a slight increase in percentage glucose. Results support the hypothesis that stochastic variations among flowers or nectaries in the taxonomic identity of recent visitors and their relative visitation frequencies may eventually generate very small-scale mosaics in nectar sugar composition. Changes in nectar sugar composition following bumblebee probing may be the consequence of nectar contamination with pollinator-borne nectarivorous yeasts.

  15. Bumblebees are not deterred by ecologically relevant concentrations of nectar toxins

    Science.gov (United States)

    Tiedeken, Erin Jo; Stout, Jane C.; Stevenson, Philip C.; Wright, Geraldine A.

    2014-01-01

    Bees visit flowers to collect nectar and pollen that contain nutrients and simultaneously facilitate plant sexual reproduction. Paradoxically, nectar produced to attract pollinators often contains deterrent or toxic plant compounds associated with herbivore defence. The functional significance of these nectar toxins is not fully understood, but they may have a negative impact on pollinator behaviour and health, and, ultimately, plant pollination. This study investigates whether a generalist bumblebee, Bombus terrestris, can detect naturally occurring concentrations of nectar toxins. Using paired-choice experiments, we identified deterrence thresholds for five compounds found in the nectar of bee-pollinated plants: quinine, caffeine, nicotine, amygdalin and grayanotoxin. The deterrence threshold was determined when bumblebees significantly preferred a sucrose solution over a sucrose solution containing the compound. Bumblebees had the lowest deterrence threshold for the alkaloid quinine (0.01 mmol l−1); all other compounds had higher deterrence thresholds, above the natural concentration range in floral nectar. Our data, combined with previous work using honeybees, suggest that generalist bee species have poor acuity for the detection of nectar toxins. The fact that bees do not avoid nectar-relevant concentrations of these compounds likely indicates that it is difficult for them to learn to associate floral traits with the presence of toxins, thus maintaining this trait in plant populations. PMID:24526720

  16. New electronics for the Cherenkov Telescope Array (NECTAr)

    Energy Technology Data Exchange (ETDEWEB)

    Naumann, C.L., E-mail: christopher.naumann@lpnhe.in2p3.fr [LPNHE, IN2P3/CNRS Universite Paris VI and Universite Paris VII and IN2P3/CNRS, Paris (France); Delagnes, E. [IRFU, CEA/DSM, Saclay, Gif-sur-Yvette (France); Bolmont, J.; Corona, P. [LPNHE, IN2P3/CNRS Universite Paris VI and Universite Paris VII and IN2P3/CNRS, Paris (France); Dzahini, D. [LPSC, Universite Joseph Fourier, INPG and IN2P3/CNRS, Grenoble (France); Feinstein, F. [LUPM, Universite Montpellier II and IN2P3/CNRS, Montpellier (France); Gascon, D. [ICC-UB, Universitat Barcelona (Spain); Glicenstein, J.-F.; Guilloux, F. [IRFU, CEA/DSM, Saclay, Gif-sur-Yvette (France); Nayman, P. [LPNHE, IN2P3/CNRS Universite Paris VI and Universite Paris VII and IN2P3/CNRS, Paris (France); Rarbi, F. [LPSC, Universite Joseph Fourier, INPG and IN2P3/CNRS, Grenoble (France); Sanuy, A. [ICC-UB, Universitat Barcelona (Spain); Tavernet, J.-P.; Toussenel, F.; Vincent, P. [LPNHE, IN2P3/CNRS Universite Paris VI and Universite Paris VII and IN2P3/CNRS, Paris (France); Vorobiov, S. [LUPM, Universite Montpellier II and IN2P3/CNRS, Montpellier (France); DESY Zeuthen, Platanenallee 6, 15738 Zeuthen (Germany)

    2012-12-11

    The international CTA consortium has recently entered into its preparatory phase towards the construction of the next-generation Cherenkov Telescope Array CTA. This experiment will be a successor, and based on the return of experience from the three major current-generation arrays H.E.S.S., MAGIC and VERITAS, and aims to significantly improve upon the sensitivity as well as the energy range of its highly successful predecessors. Construction is planned to begin by 2013, and when finished, CTA will be able to explore the highest-energy gamma ray sky in unprecedented detail. To achieve this increase in sensitivity and energy range, CTA will employ the order of 100 telescopes of three different sizes on two sites, with around 1000-4000 channels per camera, depending on the telescope size. To equip and reliably operate the order of 100000 channels of photodetectors (compared to 6000 of the H.E.S.S. array), a new kind of flexible and powerful yet inexpensive front-end hardware will be required. One possible solution is pursued by the NECTAr (New Electronics for the Cherenkov Telescope Array) project. Its main feature is the integration of as much as possible of the front-end electronics (amplifiers, fast analogue samplers, memory and ADCs) into a single ASIC, which will allow very fast readout performances while significantly reducing the cost and the power consumption per channel. Also included is a low-cost FPGA for digital treatment and online data processing, as well as an Ethernet connection. Other priorities of NECTAr are the modularity of the system, a high degree of flexibility in the trigger system as well as the possibility of flexible readout modes to optimise the signal-to-noise ratio while at the same time allowing a significant reduction of data rates, both of which could improve the sensitivity of CTA compared to current detection systems. This paper gives an overview over the development work for the Nectar system, with particular focus on its main

  17. Chronic intake of fermented floral nectar by wild treeshrews.

    Science.gov (United States)

    Wiens, Frank; Zitzmann, Annette; Lachance, Marc-André; Yegles, Michel; Pragst, Fritz; Wurst, Friedrich M; von Holst, Dietrich; Guan, Saw Leng; Spanagel, Rainer

    2008-07-29

    For humans alcohol consumption often has devastating consequences. Wild mammals may also be behaviorally and physiologically challenged by alcohol in their food. Here, we provide a detailed account of chronic alcohol intake by mammals as part of a coevolved relationship with a plant. We discovered that seven mammalian species in a West Malaysian rainforest consume alcoholic nectar daily from flower buds of the bertam palm (Eugeissona tristis), which they pollinate. The 3.8% maximum alcohol concentration (mean: 0.6%; median: 0.5%) that we recorded is among the highest ever reported in a natural food. Nectar high in alcohol is facilitated by specialized flower buds that harbor a fermenting yeast community, including several species new to science. Pentailed treeshrews (Ptilocercus lowii) frequently consume alcohol doses from the inflorescences that would intoxicate humans. Yet, the flower-visiting mammals showed no signs of intoxication. Analysis of an alcohol metabolite (ethyl glucuronide) in their hair yielded concentrations higher than those in humans with similarly high alcohol intake. The pentailed treeshrew is considered a living model for extinct mammals representing the stock from which all extinct and living treeshrews and primates radiated. Therefore, we hypothesize that moderate to high alcohol intake was present early on in the evolution of these closely related lineages. It is yet unclear to what extent treeshrews benefit from ingested alcohol per se and how they mitigate the risk of continuous high blood alcohol concentrations.

  18. Multilocus sequence analysis of nectar pseudomonads reveals high genetic diversity and contrasting recombination patterns.

    Directory of Open Access Journals (Sweden)

    Sergio Alvarez-Pérez

    Full Text Available The genetic and evolutionary relationships among floral nectar-dwelling Pseudomonas 'sensu stricto' isolates associated to South African and Mediterranean plants were investigated by multilocus sequence analysis (MLSA of four core housekeeping genes (rrs, gyrB, rpoB and rpoD. A total of 35 different sequence types were found for the 38 nectar bacterial isolates characterised. Phylogenetic analyses resulted in the identification of three main clades [nectar groups (NGs 1, 2 and 3] of nectar pseudomonads, which were closely related to five intrageneric groups: Pseudomonas oryzihabitans (NG 1; P. fluorescens, P. lutea and P. syringae (NG 2; and P. rhizosphaerae (NG 3. Linkage disequilibrium analysis pointed to a mostly clonal population structure, even when the analysis was restricted to isolates from the same floristic region or belonging to the same NG. Nevertheless, signatures of recombination were observed for NG 3, which exclusively included isolates retrieved from the floral nectar of insect-pollinated Mediterranean plants. In contrast, the other two NGs comprised both South African and Mediterranean isolates. Analyses relating diversification to floristic region and pollinator type revealed that there has been more unique evolution of the nectar pseudomonads within the Mediterranean region than would be expected by chance. This is the first work analysing the sequence of multiple loci to reveal geno- and ecotypes of nectar bacteria.

  19. Effects of elevated CO 2 on flowering phenology and nectar production

    Science.gov (United States)

    Erhardt, Andreas; Rusterholz, Hans-Peter

    Effects of elevated CO 2 on flowering phenology and nectar production were studied in five important nectar plants of calcareous grasslands, i.e. Lotus corniculatus, Trifolium pratense, Betonica officinalis, Scabiosa columbaria and Centaurea jacea. Glasshouse experiments showed that flowering probability was significantly enhanced in C. jacea. B. officinalis flowered carlier and L. corniculatus produced more flowers under elevated CO 2. In contrast, the number of flowers decreased in T. pratense. The amount of nectar produced per flower was not affected in the investigated legumes ( T. pratense, L. corniculatus), but was significantly reduced in the other forbs. Elevated CO 2 did not significantly affect nectar sugar concentration and sugar composition. However, S. columbaria and C. jacea produced significantly less total sugar per flower under elevated CO 2. The nectar amino acid concentration remained unaffected in all investigated plant species whereas the total of amino acids produced per flower was significantly reduced in all non-legumes. In addition, the amino acid composition changed significantly in all investigated species except for C. jacea. The observed effects are unexpected and are a potential threat to flower visitors such as most butterflies which have no alternative food resources except nectar. Changes in nectar production due to elevated CO 2 could also generally have detrimental effects on the interactions of flowers and their pollinators.

  20. Pyrrolizidine Alkaloids from Echium vulgare in Honey Originate Primarily from Floral Nectar.

    Science.gov (United States)

    Lucchetti, Matteo A; Glauser, Gaetan; Kilchenmann, Verena; Dübecke, Arne; Beckh, Gudrun; Praz, Christophe; Kast, Christina

    2016-06-29

    Pyrrolizidine alkaloids (PAs) in honey can be a potential human health risk. So far, it has remained unclear whether PAs in honey originate from pollen or floral nectar. We obtained honey, nectar, and plant pollen from two observation sites where Echium vulgare L. was naturally abundant. The PA concentration of honey was determined by targeted analysis using a high pressure liquid chromatography-mass spectrometry system (HPLC-MS/MS), allowing the quantification of six different PAs and PA-N-oxides present in E. vulgare. Echium-type PAs were detected up to 0.153 μg/g in honey. Nectar and plant pollen were analyzed by nontargeted analysis using ultrahigh pressure liquid chromatography-high resolution-mass spectrometry (UHPLC-HR-MS), allowing the detection of 10 alkaloids in small size samples. Echium-type PAs were detected between 0.3-95.1 μg/g in nectar and 500-35000 μg/g in plant pollen. The PA composition in nectar and plant pollen was compared to the composition in honey. Echimidine (+N-oxide) was the main alkaloid detected in honey and nectar samples, while echivulgarine (+N-oxide) was the main PA found in plant pollen. These results suggest that nectar contributes more significantly to PA contamination in honey than plant pollen.

  1. The role of abiotic environmental conditions and herbivory in shaping bacterial community composition in floral nectar.

    Science.gov (United States)

    Samuni-Blank, Michal; Izhaki, Ido; Laviad, Sivan; Bar-Massada, Avi; Gerchman, Yoram; Halpern, Malka

    2014-01-01

    Identifying the processes that drive community assembly has long been a central theme in ecology. For microorganisms, a traditional prevailing hypothesis states that "everything is everywhere, but the environment selects". Although the bacterial community in floral nectar may be affected by both atmosphere (air-borne bacteria) and animals as dispersal vectors, the environmental and geographic factors that shape microbial communities in floral nectar are unknown. We studied culturable bacterial communities in Asphodelus aestivus floral nectar and in its typical herbivorous bug Capsodes infuscatus, along an aridity gradient. Bacteria were sampled from floral nectar and bugs at four sites, spanning a geographical range of 200 km from Mediterranean to semi-arid conditions, under open and bagged flower treatments. In agreement with the niche assembly hypothesis, the differences in bacterial community compositions were explained by differences in abiotic environmental conditions. These results suggest that microbial model systems are useful for addressing macro-ecological questions. In addition, similar bacterial communities were found in the nectar and on the surface of the bugs that were documented visiting the flowers. These similarities imply that floral nectar bacteria dispersal is shaped not only by air borne bacteria and nectar consumers as previously reported, but also by visiting vectors like the mirid bugs.

  2. The role of abiotic environmental conditions and herbivory in shaping bacterial community composition in floral nectar.

    Directory of Open Access Journals (Sweden)

    Michal Samuni-Blank

    Full Text Available Identifying the processes that drive community assembly has long been a central theme in ecology. For microorganisms, a traditional prevailing hypothesis states that "everything is everywhere, but the environment selects". Although the bacterial community in floral nectar may be affected by both atmosphere (air-borne bacteria and animals as dispersal vectors, the environmental and geographic factors that shape microbial communities in floral nectar are unknown. We studied culturable bacterial communities in Asphodelus aestivus floral nectar and in its typical herbivorous bug Capsodes infuscatus, along an aridity gradient. Bacteria were sampled from floral nectar and bugs at four sites, spanning a geographical range of 200 km from Mediterranean to semi-arid conditions, under open and bagged flower treatments. In agreement with the niche assembly hypothesis, the differences in bacterial community compositions were explained by differences in abiotic environmental conditions. These results suggest that microbial model systems are useful for addressing macro-ecological questions. In addition, similar bacterial communities were found in the nectar and on the surface of the bugs that were documented visiting the flowers. These similarities imply that floral nectar bacteria dispersal is shaped not only by air borne bacteria and nectar consumers as previously reported, but also by visiting vectors like the mirid bugs.

  3. Variation in Nectar Volume and Sugar Concentration of Allium ursinum L. ssp. ucrainicum in Three Habitats

    Directory of Open Access Journals (Sweden)

    Ágnes Farkas

    2012-01-01

    Full Text Available Floral nectar volume and concentration of ramson (Allium ursinum L. ssp. ucrainicum were investigated in three different habitats, including two types of sessile oak-hornbeam association on brown forest soil with clay illuviation and a silver lime-flowering ash rock forest association on rendzina. Daily nectar production ranged from 0.1 to 3.8 μL per flower with sugar concentrations of 25 to 50%. Mean nectar volumes and concentrations showed significant differences between freely exposed flowers and covered flowers, which had been isolated from flower visitors 24 h prior to nectar studies. Both the amount and quality of nectar were affected by microclimatic conditions and soil properties and varied between populations at different habitats. In the silver lime-flowering ash rock-forest association mean nectar volumes and concentrations were lower than in a typical sessile oak-hornbeam association on three occasions, the difference being significant in two cases. During full bloom, the date of sampling did not have a profound effect on either nectar volume or concentration.

  4. Divergent rules for pollen and nectar foraging bumblebees--a laboratory study with artificial flowers offering diluted nectar substitute and pollen surrogate.

    Directory of Open Access Journals (Sweden)

    Sabine Konzmann

    Full Text Available Almost all bees collect nectar and pollen from flowers. Female bees collect pollen to provision their nest cells, whereas they use nectar for individual energy supply and nest cell provisioning. Bees fine-tune nectar foraging to the amount and to the concentration of nectar, but the individual bees' response to variability of amount and concentration of pollen reward has not yet been studied thoroughly in laboratory settings. We developed an experimental set-up in which bumblebees simultaneously collected sugar solution and pollen from artificial flowers; natural pollen was mixed with cellulose powder or glass powder as a pollen surrogate. Here we show that bumblebee (Bombus terrestris workers do not specialise in nectar or pollen collection, but regularly collect both rewards on the same day. When offered a fixed pollen reward and varied amounts and concentrations of sugar solution, the bumblebees fine-tuned sugar solution foraging dependent on both the volume and concentration, with strong preferences for the highest concentration and the greatest volume. In the reciprocal tests, when offered a fixed sugar reward and varied amounts and concentrations of pollen mixed with a nutrient-free pollen surrogate, the bumblebees follow more an all-or-none rule for pollen, accepting all amounts and concentrations except pure surrogate. It is discussed how the bumblebees' ability to sense sugar, and their apparent inability to sense the pollen protein content, shaped their foraging behaviour. It is argued that the rarity of nectar mimicry and the frequency of pollen mimicry in natural flowers might be interpreted in the context of divergent abilities of nectar and pollen recognition in bees.

  5. A native plant competitor mediates the impact of above- and belowground damage on an invasive tree.

    Science.gov (United States)

    Carrillo, Juli; Siemann, Evan

    2016-10-01

    Plant competition may mediate the impacts of herbivory on invasive plant species through effects on plant growth and defense. This may predictably depend on whether herbivory occurs above or below ground and on relative plant competitive ability. We simulated the potential impact of above- or belowground damage by biocontrol agents on the growth of a woody invader (Chinese tallow tree, Triadica sebifera) through artificial herbivory, with or without competition with a native grass, little bluestem (Schizachyrium scoparium). We measured two defense responses of Triadica through quantifying constitutive and induced extrafloral nectar production and tolerance of above- and belowground damage (root and shoot biomass regrowth). We examined genetic variation in plant growth and defense across native (China) and invasive (United States) Triadica populations. Without competition, aboveground damage had a greater impact than belowground damage on Triadica performance, whereas with competition and above- and belowground damage impacted Triadica similarly. Whole plant tolerance to damage below ground was negatively associated with tolerance to grass competitors indicating tradeoffs in the ability to tolerate herbivory vs. compete. Competition reduced investment in defensive extrafloral nectar (EFN) production. Aboveground damage inhibited rather than induced EFN production while belowground plant damage did not impact aboveground nectar production. We found some support for the evolution of increased competitive ability hypothesis for invasive plants as United States plants were larger than native China plants and were more plastic in their response to biotic stressors than China plants (they altered their root to shoot ratios dependent on herbivory and competition treatments). Our results indicate that habitat type and the presence of competitors may be a larger determinant of herbivory impact than feeding mode and suggest that integrated pest management strategies including

  6. Historical nectar assessment reveals the fall and rise of floral resources in Britain

    Science.gov (United States)

    Baude, Mathilde; Kunin, William E.; Boatman, Nigel D.; Conyers, Simon; Davies, Nancy; Gillespie, Mark A. K.; Morton, R. Daniel; Smart, Simon M.; Memmott, Jane

    2016-02-01

    There is considerable concern over declines in insect pollinator communities and potential impacts on the pollination of crops and wildflowers. Among the multiple pressures facing pollinators, decreasing floral resources due to habitat loss and degradation has been suggested as a key contributing factor. However, a lack of quantitative data has hampered testing for historical changes in floral resources. Here we show that overall floral rewards can be estimated at a national scale by combining vegetation surveys and direct nectar measurements. We find evidence for substantial losses in nectar resources in England and Wales between the 1930s and 1970s; however, total nectar provision in Great Britain as a whole had stabilized by 1978, and increased from 1998 to 2007. These findings concur with trends in pollinator diversity, which declined in the mid-twentieth century but stabilized more recently. The diversity of nectar sources declined from 1978 to 1990 and thereafter in some habitats, with four plant species accounting for over 50% of national nectar provision in 2007. Calcareous grassland, broadleaved woodland and neutral grassland are the habitats that produce the greatest amount of nectar per unit area from the most diverse sources, whereas arable land is the poorest with respect to amount of nectar per unit area and diversity of nectar sources. Although agri-environment schemes add resources to arable landscapes, their national contribution is low. Owing to their large area, improved grasslands could add substantially to national nectar provision if they were managed to increase floral resource provision. This national-scale assessment of floral resource provision affords new insights into the links between plant and pollinator declines, and offers considerable opportunities for conservation.

  7. Study on beam geometry and image reconstruction algorithm in fast neutron computerized tomography at NECTAR facility

    Energy Technology Data Exchange (ETDEWEB)

    Guo, J. [State Key Laboratory of Nuclear Physics and Technology and School of Physics, Peking University, 5 Yiheyuan Lu, Beijing 100871 (China); Lehrstuhl fuer Radiochemie, Technische Universitaet Muenchen, Garching 80748 (Germany); Buecherl, T. [Lehrstuhl fuer Radiochemie, Technische Universitaet Muenchen, Garching 80748 (Germany); Zou, Y., E-mail: zouyubin@pku.edu.cn [State Key Laboratory of Nuclear Physics and Technology and School of Physics, Peking University, 5 Yiheyuan Lu, Beijing 100871 (China); Guo, Z. [State Key Laboratory of Nuclear Physics and Technology and School of Physics, Peking University, 5 Yiheyuan Lu, Beijing 100871 (China)

    2011-09-21

    Investigations on the fast neutron beam geometry for the NECTAR facility are presented. The results of MCNP simulations and experimental measurements of the beam distributions at NECTAR are compared. Boltzmann functions are used to describe the beam profile in the detection plane assuming the area source to be set up of large number of single neutron point sources. An iterative algebraic reconstruction algorithm is developed, realized and verified by both simulated and measured projection data. The feasibility for improved reconstruction in fast neutron computerized tomography at the NECTAR facility is demonstrated.

  8. NECTAR-A fission neutron radiography and tomography facility

    Energy Technology Data Exchange (ETDEWEB)

    Buecherl, T., E-mail: thomas.buecherl@radiochemie.de [Technische Universitaet Muenchen, Lehrstuhl fuer Radiochemie (RCM), Walther-Meissner-Str. 3, 85748 Garching (Germany); Lierse von Gostomski, Ch. [Technische Universitaet Muenchen, Lehrstuhl fuer Radiochemie (RCM), Walther-Meissner-Str. 3, 85748 Garching (Germany); Breitkreutz, H.; Jungwirth, M.; Wagner, F.M. [Technische Universitaet Muenchen, Forschungs-Neutronenquelle Heinz Maier-Leibnitz (FRM II) (Germany)

    2011-09-21

    NECTAR (Neutron Computerized Tomography and Radiography) is a versatile facility for radiographic and tomographic investigations as well as for neutron activation experiments using fission neutrons. The radiation sources for this facility are two plates of highly enriched uranium situated in the moderator vessel in FRM II. Thermal neutrons originating from the main fuel element of the reactor generate in these plates fast neutrons. These can escape through a horizontal beam tube without moderation. The beam can be filtered and manipulated in order to reduce the accompanying gamma radiation and to match the specific experimental tasks. A summary of the main parameters required for experimental set-up and (quantitative) data evaluation is presented. The (measured) spectra of the neutron and gamma radiations are shown along with the effect of different filters on their behavior. The neutron and gamma fluxes, dose rates, L/D-ratios, etc. and the main parameters of the actually used detection systems for neutron imaging are given, too.

  9. Main sugar composition of floral nectar in three species groups of Scrophularia (Scrophulariaceae) with different principal pollinators.

    Science.gov (United States)

    Rodríguez-Riaño, T; Ortega-Olivencia, A; López, J; Pérez-Bote, J L; Navarro-Pérez, M L

    2014-11-01

    In some angiosperm groups, a parallelism between nectar traits and pollination syndromes has been demonstrated, whereas in others there is not such relationship and it has been explained as due to phylogenetic constraints. However, nectar trait information remains scarce for many plant groups. This paper focuses on three groups of Scrophularia species, with different flower sizes and principal pollinators, to find out whether nectar sugar composition is determined by pollinator type or reflects taxonomic affinities. Since the species we examined have protogynous flowers, and gender bias in nectar sugar composition has been noted in few plant groups, we also investigated whether sexual phase influenced Scrophularia nectar composition. The sugar composition was found to be similar in all species, having high-sucrose nectar, except for the Macaronesian Scrophularia calliantha, which was the only species with balanced nectar; this last kind of nectar could be associated with the high interaction rates observed between S. calliantha and passerine birds. The nectar sugar composition (high in sucrose) was unrelated to the principal pollinator group, and could instead be considered a conservative taxonomic trait. No gender bias was observed between functionally female and male flowers for nectar volume or concentration. However, sexual phase significantly affected sucrose percentage in the largest-flowered species, where the female phase flowers had higher sucrose percentages than the male phase flowers. © 2014 German Botanical Society and The Royal Botanical Society of the Netherlands.

  10. Floral nectary, nectar production dynamics and chemical composition in five nocturnal Oenothera species (Onagraceae) in relation to floral visitors.

    Science.gov (United States)

    Antoń, Sebastian; Komoń-Janczara, Elwira; Denisow, Bożena

    2017-08-04

    Main conclusion The floral nectars were sucrose-dominant; however, nectar protein and amino acid contents differed, indicating that composition of nitrogenous compounds may vary considerably even between closely related plant species, irrespectively of nectary structure. Numerous zoophilous plants attract their pollinators by offering floral nectar; an aqueous solution produced by specialized secretory tissues, known as floral nectaries. Although many papers on nectaries and nectar already exist, there has been a little research into the structure of nectaries and/or nectar production and composition in species belonging to the same genus. To redress this imbalance, we sought, in the present paper, to describe the floral nectary, nectar production, and nectar composition in five nocturnal Oenothera species with respect to their floral visitors. The structure of nectaries was similar for all the species investigated, and comprised the epidermis (with nectarostomata), numerous layers of nectary parenchyma, and subsecretory parenchyma. Anthesis for a single flower was short (ca. 10-12 h), and flowers lasted only one night. The release of floral nectar commenced at the bud stage (approx. 4 h before anthesis) and nectar was available to pollinators until petal closure. Nectar concentration was relatively low (ca. 27%) and the nectar was sucrose-dominant, and composed mainly of sucrose, glucose and fructose. The protein content of the nectar was also relatively low (on average, 0.31 µg ml(-1)). Nevertheless, a great variety of amino acids, including both protein and non-protein types, was detected in the nectar profile of the investigated taxa. We noted both diurnal and nocturnal generalist, opportunistic floral insect visitors.

  11. Assessing the suitability of flowering herbs as parasitoid food sources: flower attractiveness and nectar accessibility

    NARCIS (Netherlands)

    Wäckers, F.L.

    2004-01-01

    Eleven insect-pollinated plant species were investigated with respect to their olfactory attractiveness and nectar accessibility for the parasitoid species Cotesia glomerata (Hymenoptera: Braconidae), Heterospilus prosopidis (Hymenoptera: Braconidae), and Pimpla turionellae (Hymenoptera: Ichneumonid

  12. Nectar secretion dynamics and honey production potentials of some major honey plants in Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Nuru Adgaba

    2017-01-01

    Full Text Available The contribution of a bee plant species to honey production depends on the plant’s nectar secretion quality and quantity, which is mainly governed by biotic and abiotic factors. The aim of the current study, was to investigate the nectar secretion dynamics and honey production potential of 14 major bee plant species of the target area. We examined the quantity and dynamics of nectar sugar per flower five times a day using a nectar sugar washing technique and direct measuring of nectar with calibrated capillary tubes. The average nectar sugar amount of the species varied from 0.41 mg/flower to 7.7 mg/flower (P < 0.0001. The honey sugar per flower was used to extrapolate the honey production potential per plant and per hectare of land. Accordingly the honey production potential of the species observed to vary from 14 kg/hectare in Otostegia fruticosa to 829 kg/hectare in Ziziphus spina-christi. The nectar secretion dynamics of the species generally showed an increasing trend early in the morning, peaking toward midday, followed by a decline but different species observed to have different peak nectar secretion times. Generally, the tree species secreted more nectar sugar/flower than the herbs. The nectar secretion amount of the species was positively correlated with the ambient temperature, indicating the adaptation of the species to hot climatic conditions. However, different species were observed to have a different optimum temperature for peak nectar secretion. Despite the limited rainfall and high temperature of the area, many plants were found to have good potential for honey production. The monetary value of honey per hectare of the studied honeybee plant species can be of equal or greater than the per-hectare monetary value of some cultivated crops that require numerous inputs. In addition, the information generated is believed to be useful in apiary site selection and to estimate the honey bee colony carrying capacity of an area.

  13. The role of ant-tended extrafloral nectaries in the protection and benefit of a Neotropical rainforest tree.

    Science.gov (United States)

    de la Fuente, Marie Ann S; Marquis, Robert J

    1999-02-01

    One possible function of extrafloral nectaries is to attract insects, particularly ants, which defend plants from herbivores. We determined whether ants visiting saplings of the tree Stryphnodendronmicrostachyum (Leguminosae) provide protection (decreased plant damage due to ant molestation or killing of herbivores) and benefit (increased plant growth and reproduction associated with ant presence) to the plant. We compared ant and herbivore abundance, herbivore damage and growth of ant-visited plants and ant-excluded plants grown in sun and shade microhabitats of a 6-ha plantation in Costa Rica over a 7-month period. Results show that ants provided protection to plants not by reducing herbivore numbers but by molesting herbivores. Ants also reduced the incidence of pathogen attack on leaves. Protection was greater in the shade than in the sun, probably due to lower herbivore attack in the sun. Protection was also variable within sun and shade habitats, and this variability appeared to be related to variable ant visitation. Results also indicate that ant presence benefits the plant: ant-visited plants grew significantly more in height than ant-excluded plants. The cultivation of ants may serve as an important natural biological control in tropical forestry and agroforestry systems, where increased plant density can otherwise lead to increased herbivore attack.

  14. The Role of Abiotic Environmental Conditions and Herbivory in Shaping Bacterial Community Composition in Floral Nectar

    OpenAIRE

    Michal Samuni-Blank; Ido Izhaki; Sivan Laviad; Avi Bar-Massada; Yoram Gerchman; Malka Halpern

    2014-01-01

    Identifying the processes that drive community assembly has long been a central theme in ecology. For microorganisms, a traditional prevailing hypothesis states that "everything is everywhere, but the environment selects". Although the bacterial community in floral nectar may be affected by both atmosphere (air-borne bacteria) and animals as dispersal vectors, the environmental and geographic factors that shape microbial communities in floral nectar are unknown. We studied culturable bacteria...

  15. Factors affecting the thermal activation of Neosartorya fischeri in pineapple and papaya nectars

    OpenAIRE

    Slongo, Adriana Paula; Aragão,Gláucia Maria Falcão de

    2006-01-01

    In this research factors that influence the activation of Neosartorya fischeri ascospores (heating medium, temperature of production and age of the ascospores) were studied. The heating medium used was pineapple and papaya nectars at different ratios (ºBrix/acidity). Lower activation times were observed for the N. fischeri ascospores in pineapple and papaya nectars under the conditions of temperature and production age of 25ºC for 1 month and using ratios of the heating medium of 10 for pinea...

  16. Dilute bird nectars: viscosity constrains food intake by licking in a sunbird.

    Science.gov (United States)

    Köhler, Angela; Leseigneur, Carolina D C; Verburgt, Luke; Nicolson, Susan W

    2010-10-01

    Floral nectars of bird-pollinated plants are relatively dilute. One hypothesis proposed to explain this concerns the difficulty for birds of drinking nectar of high viscosity. We examined the effects of viscosity, separately from those of sugar concentration, on feeding by captive whitebellied sunbirds (Cinnyris talatala). Viscosities of artificial nectar (sucrose solutions ranging in concentration from 0.25 to 1.5 mol/l) were altered with Tylose, an inert polysaccharide. Food consumption was measured over 3 h, and lick frequency and duration were recorded using photodetection devices on feeding apertures too small for the bill but large enough for the extended tongue. Volumetric intake rates (ml/s) were inversely proportional to nectar viscosity, and were similar over the range of sucrose concentrations when viscosity was held constant. Sucrose intake rates (mg/s) remained the same on pure sucrose solutions, but they decreased with increasing viscosity at a constant sucrose concentration. Lick frequencies and tongue loads were reduced at high viscosities, and lick duration increased, which confirms that sunbirds take longer to ingest viscous solutions. Licking behavior was remarkably similar in birds feeding on different sucrose concentrations if viscosity was held constant. Nectar ingestion rate is determined by viscosity; however, total food intake is mainly modulated by sugar concentration. Similar effects of food viscosity have been observed in insects that suck nectar.

  17. Nectar robbing positively influences the reproductive success of Tecomella undulata (Bignoniaceae.

    Directory of Open Access Journals (Sweden)

    Vineet Kumar Singh

    Full Text Available The net consequence of nectar robbing on reproductive success of plants is usually negative and the positive effect is rarely produced. We evaluated the influence of nectar robbing on the behaviour of pollinators and the reproductive success of Tecomella undulata (Bignoniaceae in a natural population. Experimental pollinations showed that the trees were strictly self-incompatible. The three types of floral colour morphs of the tree viz. red, orange and yellow, lacked compatibility barriers. The pollinators (Pycnonotus cafer and Pycnonotus leucotis and the robber (Nectarinia asiatica showed equal preference for all the morphs, as they visited each morph with nearly equal frequency and flower-handling time. The sunbirds caused up to 60% nectar robbing, mostly (99% by piercing through the corolla tube. Although nectar is replenished at regular intervals, insufficient amount of nectar compelled the pollinators to visit additional trees in bloom. Data of manual nectar robbing from the entire tree showed that the pollinators covered lower number of flowers per tree (5 flowers/tree and more trees per bout (7 trees/bout than the unrobbed ones (19 flowers/tree and 2 trees bout. The robbed trees set a significantly greater amount of fruits than the unrobbed trees. However, the number of seeds in a fruit did not differ significantly. The study shows that plant-pollinator-robber interaction may benefit the self-incompatible plant species under conditions that increases the visits of pollinators among the compatible conspecifics in a population.

  18. Nectar robbing positively influences the reproductive success of Tecomella undulata (Bignoniaceae).

    Science.gov (United States)

    Singh, Vineet Kumar; Barman, Chandan; Tandon, Rajesh

    2014-01-01

    The net consequence of nectar robbing on reproductive success of plants is usually negative and the positive effect is rarely produced. We evaluated the influence of nectar robbing on the behaviour of pollinators and the reproductive success of Tecomella undulata (Bignoniaceae) in a natural population. Experimental pollinations showed that the trees were strictly self-incompatible. The three types of floral colour morphs of the tree viz. red, orange and yellow, lacked compatibility barriers. The pollinators (Pycnonotus cafer and Pycnonotus leucotis) and the robber (Nectarinia asiatica) showed equal preference for all the morphs, as they visited each morph with nearly equal frequency and flower-handling time. The sunbirds caused up to 60% nectar robbing, mostly (99%) by piercing through the corolla tube. Although nectar is replenished at regular intervals, insufficient amount of nectar compelled the pollinators to visit additional trees in bloom. Data of manual nectar robbing from the entire tree showed that the pollinators covered lower number of flowers per tree (5 flowers/tree) and more trees per bout (7 trees/bout) than the unrobbed ones (19 flowers/tree and 2 trees bout). The robbed trees set a significantly greater amount of fruits than the unrobbed trees. However, the number of seeds in a fruit did not differ significantly. The study shows that plant-pollinator-robber interaction may benefit the self-incompatible plant species under conditions that increases the visits of pollinators among the compatible conspecifics in a population.

  19. Sex differential nectar secretion in protandrous Alstroemeria aurea (Alstroemeriaceae): is production altered by pollen removal and receipt?

    Science.gov (United States)

    Aizen, M; Basilio, A

    1998-02-01

    We examined diurnal and nocturnal nectar secretion across sexual stages in protandrous Alstroemeria aurea, a bumble bee-pollinated herb with long-lived flowers native to the southern Andes. We found the following patterns: (1) most nectar was produced diurnally and (2) three times more sugar was secreted during the male than female phase, not only because the male phase lasted longer but also because the rate of nectar production was higher. This 3:1 ratio in nectar production matched the ratio of the minimum number of bumble bee visits required on average to saturate male (pollen removal) vs. female (seed set) functions. Standing crop of nectar, on the other hand, did not differ greatly between male- and female- stage flowers left open to visitors, because the high-production male-phase flowers were visited more frequently than female- phase flowers. In an experiment concurrent with the repeated nectar sampling of individual flowers over their life-span, we removed pollen from anthers or deposited pollen on stigmas by hand. Neither treatment, designed to mimic effects of visits by Alstroemeria's native bumble bee pollinator, affected nectar production. The absence of plasticity in nectar secretion in relation to pollination events may reflect a low cost of nectar production, or may result from developmental constraints related to the evolution of the synchronous protandry that characterizes A. aurea.

  20. Yeasts in nectar of an early-blooming herb: sought by bumble bees, detrimental to plant fecundity.

    Science.gov (United States)

    Herrera, Carlos M; Pozo, María I; Medrano, Mónica

    2013-02-01

    Through their effects on physicochemical features of floral nectar, nectar-dwelling yeasts can alter pollinator behavior, but the effect of such changes on pollination success and plant reproduction is unknown. We present results of experiments testing the effects of nectar yeasts on foraging patterns of captive and free-ranging bumble bees, and also on pollination success and fecundity of the early-blooming, bumble bee-pollinated Helleborus foetidus (Ranunculaceae). Under controlled experimental conditions, inexperienced Bombus terrestris workers responded positively to the presence of yeasts in artificial sugar solutions mimicking floral nectar by visiting proportionally more yeast-containing artificial flowers. Free-ranging bumble bees also preferred yeast-containing nectar in the field. Experiments conducted in two different years consistently showed that natural and artificial nectars containing yeasts were more thoroughly removed than nectars without yeasts. Experimental yeast inoculation of the nectar of H. foetidus flowers was significantly associated with reductions in number of pollen tubes in the style, fruit set, seed set, and mass of individual seeds produced. These results provide the first direct evidence to date that nectar yeasts can modify pollinator foraging patterns, pollination success, and the quantity and quality of seeds produced by insect-pollinated plants.

  1. Divergent investment strategies of Acacia myrmecophytes and the coexistence of mutualists and exploiters.

    Science.gov (United States)

    Heil, Martin; González-Teuber, Marcia; Clement, Lars W; Kautz, Stefanie; Verhaagh, Manfred; Bueno, Juan Carlos Silva

    2009-10-27

    Ant-plant interactions represent a diversity of strategies, from exploitative to mutualistic, and how these strategies evolve is poorly understood. Here, we link physiological, ecological, and phylogenetic approaches to study the evolution and coexistence of strategies in the Acacia-Pseudomyrmex system. Host plant species represented 2 different strategies. High-reward hosts produced significantly more extrafloral nectar (EFN), food bodies, and nesting space than low-reward hosts, even when being inhabited by the same species of ant mutualist. High-reward hosts were more effectively defended against herbivores and exploited to a lower extent by nondefending ants than low-reward hosts. At the phenotypic level, secretion of EFN and ant activity were positively correlated and a mutualistic ant species induced nectar secretion, whereas a nondefending exploiter did not. All of these mechanisms contribute to the stable association of high-reward hosts with defending ant species. However, exploiter ants are less dependent on the host-derived rewards and can colonize considerable proportions of the low-reward hosts. Mapping these strategies onto phylogenetic trees demonstrated that the low-reward hosts represent the derived clade within a monophyletic group of obligate ant plants and that the observed exploiter ant species evolved their strategy without having a mutualistic ancestor. We conclude that both types of host strategies coexist because of variable net outcomes of different investment-payoff regimes and that the effects of exploiters on the outcome of mutualisms can, thus, increase the diversity within the taxa involved.

  2. Inhospitable sweetness: nectar filtering of pollinator-borne inocula leads to impoverished, phylogenetically clustered yeast communities

    Science.gov (United States)

    Herrera, Carlos M.; Canto, Azucena; Pozo, María I.; Bazaga, Pilar

    2010-01-01

    Identifying the rules and mechanisms that determine the composition and diversity of naturally co-occurring species assemblages is a central topic in community ecology. Although micro-organisms represent the ‘unseen majority’ of species, individuals and biomass in many ecosystems and play pivotal roles in community development and function, the study of the factors influencing the assembly of microbial communities has lagged behind that of plant and animal communities. In this paper, we investigate experimentally the mechanisms accounting for the low species richness of yeast communities inhabiting the nectar of the bumble-bee-pollinated Helleborus foetidus (Ranunculaceae), and explore the relationships between community assembly rules and phylogenetic relatedness. By comparing yeast communities on the glossae of foraging bumble-bees (the potential species pool) with those eventually establishing in virgin nectar probed with bee glossae (the realized community), we address the questions: (i) does nectar filter yeast inocula, so that the communities eventually established there are not random subsamples of species on bumble-bee glossae? and (ii) do yeast communities establishing in H. foetidus nectar exhibit some phylogenetic bias relative to the species pool on bumble-bee glossae? Results show that nectar filtering leads to species-poor, phylogenetically clustered yeast communities that are a predictable subset of pollinator-borne inocula. Such strong habitat filtering is probably due to H. foetidus nectar representing a harsh environment for most yeasts, where only a few phylogenetically related nectar specialists physiologically endowed to tolerate a combination of high osmotic pressure and fungicidal compounds are able to develop. PMID:19889702

  3. Communication of the Association of Environmentalists for Nuclear Energy (EFN) at the Johannesburg world summit in august 2002; Communication de l'Association des Ecologistes pour le Nucleaire (AEPN) au sommet mondial de Johannesbourg aout 2002

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-07-01

    Very little is completely proven about how the increased greenhouse effect will change the world climate. Meanwhile the high probability that dramatic event will occurs, leads us to apply the precautionary principle. Facing this giant problem, EFN believes that mankind, and especially countries members of OECD, must undertake several kinds of actions, explained in this paper: reducing energy waste, develop the renewable energies, take into account the potentialities of the nuclear energy and accept the market in CO{sub 2} emission credits. (A.L.B.)

  4. Nectar Meals of a Mosquito-Specialist Spider

    Directory of Open Access Journals (Sweden)

    Josiah O. Kuja

    2012-01-01

    Full Text Available Evarcha culicivora, an East African jumping spider, is known for feeding indirectly on vertebrate blood by actively choosing blood-carrying mosquitoes as prey. Using cold-anthrone tests to detect fructose, we demonstrate that E. culicivora also feeds on nectar. Field-collected individuals, found on the plant Lantana camara, tested positive for plant sugar (fructose. In the laboratory, E. culicivora tested positive for fructose after being kept with L. camara or one of another ten plant species (Aloe vera, Clerodendron magnifica, Hamelia patens, Lantana montevideo, Leonotis nepetaefolia, Parthenium hysterophorus, Ricinus communis, Senna didymobotrya, Striga asiatica, and Verbena trivernia. Our findings demonstrate that E. culicivora acquires fructose from its natural diet and can ingest fructose directly from plant nectaries. However, experiments in the laboratory also show that E. culicivora can obtain fructose indirectly by feeding on prey that have fed on fructose, implying a need to consider this possibility when field-collected spiders test positive for fructose. In laboratory tests, 53.5% of 1,215 small juveniles, but only 3.4% of 622 adult E. culicivora, left with plants for 24 hours, were positive for fructose. These findings, along with the field data, suggest that fructose is especially important for early-instar juveniles of E. culicivora.

  5. NECTAr: New electronics for the Cherenkov Telescope Array

    Energy Technology Data Exchange (ETDEWEB)

    Vorobiov, S., E-mail: vorobiov@lpta.in2p3.f [LPTA, Universite Montpellier II and IN2P3/CNRS, Montpellier (France); Bolmont, J.; Corona, P. [LPNHE, Universite Paris VI and IN2P3/CNRS, Paris (France); Delagnes, E. [IRFU/DSM/CEA, Saclay, Gif-sur-Yvette (France); Feinstein, F. [LPTA, Universite Montpellier II and IN2P3/CNRS, Montpellier (France); Gascon, D. [ICC-UB, Universitat Barcelona, Barcelona (Spain); Glicenstein, J.-F. [IRFU/DSM/CEA, Saclay, Gif-sur-Yvette (France); Naumann, C.L.; Nayman, P. [LPNHE, Universite Paris VI and IN2P3/CNRS, Paris (France); Sanuy, A. [ICC-UB, Universitat Barcelona, Barcelona (Spain); Toussenel, F.; Vincent, P. [LPNHE, Universite Paris VI and IN2P3/CNRS, Paris (France)

    2011-05-21

    The European astroparticle physics community aims to design and build the next generation array of Imaging Atmospheric Cherenkov Telescopes (IACTs), that will benefit from the experience of the existing H.E.S.S. and MAGIC detectors, and further expand the very-high energy astronomy domain. In order to gain an order of magnitude in sensitivity in the 10 GeV to >100TeV range, the Cherenkov Telescope Array (CTA) will employ 50-100 mirrors of various sizes equipped with 1000-4000 channels per camera, to be compared with the 6000 channels of the final H.E.S.S. array. A 3-year program, started in 2009, aims to build and test a demonstrator module of a generic CTA camera. We present here the NECTAr design of front-end electronics for the CTA, adapted to the trigger and data acquisition of a large IACTs array, with simple production and maintenance. Cost and camera performances are optimized by maximizing integration of the front-end electronics (amplifiers, fast analog samplers, ADCs) in an ASIC, achieving several GS/s and a few {mu}s readout dead-time. We present preliminary results and extrapolated performances from Monte Carlo simulations.

  6. Comparison of sugars, iridoid glycosides and amino acids in nectar and phloem sap of Maurandya barclayana, Lophospermum erubescens, and Brassica napus.

    Science.gov (United States)

    Lohaus, Gertrud; Schwerdtfeger, Michael

    2014-01-01

    Floral nectar contains sugars and amino acids to attract pollinators. In addition, nectar also contains different secondary compounds, but little is understood about their origin or function. Does nectar composition reflect phloem composition, or is nectar synthesized and/or modified in nectaries? Studies where both, the nectar as well as the phloem sap taken from the same plant species were analyzed in parallel are rare. Therefore, phloem sap and nectar from different plant species (Maurandya barclayana, Lophospermum erubescens, and Brassica napus) were compared. Nectar was collected with microcapillary tubes and phloem sap with the laser-aphid-stylet technique. The nectar of all three plant species contained high amounts of sugars with different percentages of glucose, fructose, and sucrose, whereas phloem sap sugars consisted almost exclusively of sucrose. One possible reason for this could be the activity of invertases in the nectaries. The total concentration of amino acids was much lower in nectars than in phloem sap, indicating selective retention of nitrogenous solutes during nectar formation. Nectar amino acid concentrations were negatively correlated with the nectar volumes per flower of the different plant species. Both members of the tribe Antirrhineae (Plantaginaceae) M. barclayana and L. erubescens synthesized the iridoid glycoside antirrhinoside. High amounts of antirrhinoside were found in the phloem sap and lower amounts in the nectar of both plant species. The parallel analyses of nectar and phloem sap have shown that all metabolites which were found in nectar were also detectable in phloem sap with the exception of hexoses. Otherwise, the composition of both aqueous solutions was not the same. The concentration of several metabolites was lower in nectar than in phloem sap indicating selective retention of some metabolites. Furthermore, the existence of antirrhinoside in nectar could be based on passive secretion from the phloem.

  7. Analyses of avocado (Persea americana) nectar properties and their perception by honey bees (Apis mellifera).

    Science.gov (United States)

    Afik, O; Dag, A; Kerem, Z; Shafir, S

    2006-09-01

    Honey bees are important avocado pollinators. However, due to the low attractiveness of flowers, pollination is often inadequate. Previous work has revealed that avocado honey is relatively unattractive to honey bees when compared with honey from competing flowers. We characterized avocado honey and nectar with respect to their odor, color, and composition of sugars, phenolic compounds, and minerals. Furthermore, we tested how honey bees perceive these parameters, using the proboscis extension response bioassay and preference experiments with free-flying bees. Naïve bees were indifferent to odors of avocado and citrus flowers and honey. Experienced bees, which were collected in the field during the blooming season, responded preferentially to odor of citrus flowers. The unique sugar composition of avocado nectar, which contains almost exclusively sucrose and a low concentration of the rare carbohydrate perseitol, and the dark brown color of avocado honey, had no negative effects on its attractiveness to the bees. Phenolic compounds extracted from avocado honey were attractive to bees and adding them to a solution of sucrose increased its attractiveness. Compared with citrus nectar and nonavocado honey, avocado nectar and honey were rich in a wide range of minerals, including potassium, phosphorus, magnesium, sulfur, iron, and copper. Potassium and phosphorus, the two major minerals, both had a repellent effect on the bees. Possible explanations for the presence of repellent components in avocado nectar are discussed.

  8. Nectar secretion requires sucrose phosphate synthases and the sugar transporter SWEET9.

    Science.gov (United States)

    Lin, I Winnie; Sosso, Davide; Chen, Li-Qing; Gase, Klaus; Kim, Sang-Gyu; Kessler, Danny; Klinkenberg, Peter M; Gorder, Molly K; Hou, Bi-Huei; Qu, Xiao-Qing; Carter, Clay J; Baldwin, Ian T; Frommer, Wolf B

    2014-04-24

    Angiosperms developed floral nectaries that reward pollinating insects. Although nectar function and composition have been characterized, the mechanism of nectar secretion has remained unclear. Here we identify SWEET9 as a nectary-specific sugar transporter in three eudicot species: Arabidopsis thaliana, Brassica rapa (extrastaminal nectaries) and Nicotiana attenuata (gynoecial nectaries). We show that SWEET9 is essential for nectar production and can function as an efflux transporter. We also show that sucrose phosphate synthase genes, encoding key enzymes for sucrose biosynthesis, are highly expressed in nectaries and that their expression is also essential for nectar secretion. Together these data are consistent with a model in which sucrose is synthesized in the nectary parenchyma and subsequently secreted into the extracellular space via SWEET9, where sucrose is hydrolysed by an apoplasmic invertase to produce a mixture of sucrose, glucose and fructose. The recruitment of SWEET9 for sucrose export may have been a key innovation, and could have coincided with the evolution of core eudicots and contributed to the evolution of nectar secretion to reward pollinators.

  9. Movement of soil-applied imidacloprid and thiamethoxam into nectar and pollen of squash (Cucurbita pepo).

    Science.gov (United States)

    Stoner, Kimberly A; Eitzer, Brian D

    2012-01-01

    There has been recent interest in the threat to bees posed by the use of systemic insecticides. One concern is that systemic insecticides may translocate from the soil into pollen and nectar of plants, where they would be ingested by pollinators. This paper reports on the movement of two such systemic neonicotinoid insecticides, imidacloprid and thiamethoxam, into the pollen and nectar of flowers of squash (Cucurbita pepo cultivars "Multipik," "Sunray" and "Bush Delicata") when applied to soil by two methods: (1) sprayed into soil before seeding, or (2) applied through drip irrigation in a single treatment after transplant. All insecticide treatments were within labeled rates for these compounds. Pollen and nectar samples were analyzed using a standard extraction method widely used for pesticides (QuEChERS) and liquid chromatography mass spectrometric analysis. The concentrations found in nectar, 10 ± 3 ppb (mean ± s.d) for imidacloprid and 11 ± 6 ppb for thiamethoxam, are higher than concentrations of neonicotinoid insecticides in nectar of canola and sunflower grown from treated seed, and similar to those found in a recent study of neonicotinoids applied to pumpkins at transplant and through drip irrigation. The concentrations in pollen, 14 ± 8 ppb for imidacloprid and 12 ± 9 ppb for thiamethoxam, are higher than those found for seed treatments in most studies, but at the low end of the range found in the pumpkin study. Our concentrations fall into the range being investigated for sublethal effects on honey bees and bumble bees.

  10. Changes in nectar supply: A possible cause of widespread butterfly decline

    Institute of Scientific and Technical Information of China (English)

    Michiel F.WALLISDEVRIES; Chris A.M.Van SWAAY; Calijn L.PLATE

    2012-01-01

    Recent studies have documented declining trends of various groups of flower-visiting insects,even common butterfly species.Causes of these declines are still unclear but the loss of habitat quality across the wider countryside is thought to be a major factor.Nectar supply constitutes one of the main resources determining habitat quality.Yet,data on changes in nectar abundance are lacking.In this study,we provide the first analysis of changes in floral nectar abundance on a national scale and link these data to trends in butterfly species richness and abundance.We used transect data from the Dutch Butterfly Monitoring Scheme to compare two time periods:1994-1995 and 2007-2008.The results show that butterfly decline can indeed be linked to a substantial decline in overall flower abundance and specific nectar plants,such as thistles.The decline is as severe in reported flower generalists as in flower specialists.We suggest that eutrophication is a main cause of the decline of nectar sources.

  11. Nectar resource limitation affects butterfly flight performance and metabolism differently in intensive and extensive agricultural landscapes.

    Science.gov (United States)

    Lebeau, Julie; Wesselingh, Renate A; Van Dyck, Hans

    2016-05-11

    Flight is an essential biological ability of many insects, but is energetically costly. Environments under rapid human-induced change are characterized by habitat fragmentation and may impose constraints on the energy income budget of organisms. This may, in turn, affect locomotor performance and willingness to fly. We tested flight performance and metabolic rates in meadow brown butterflies (Maniola jurtina) of two contrasted agricultural landscapes: intensively managed, nectar-poor (IL) versus extensively managed, nectar-rich landscapes (EL). Young female adults were submitted to four nectar treatments (i.e. nectar quality and quantity) in outdoor flight cages. IL individuals had better flight capacities in a flight mill and had lower resting metabolic rates (RMR) than EL individuals, except under the severest treatment. Under this treatment, RMR increased in IL individuals, but decreased in EL individuals; flight performance was maintained by IL individuals, but dropped by a factor 2.5 in EL individuals. IL individuals had more canalized (i.e. less plastic) responses relative to the nectar treatments than EL individuals. Our results show significant intraspecific variation in the locomotor and metabolic response of a butterfly to different energy income regimes relative to the landscape of origin. Ecophysiological studies help to improve our mechanistic understanding of the eco-evolutionary impact of anthropogenic environments on rare and widespread species. © 2016 The Author(s).

  12. Non-target effects of fungicides on nectar-inhabiting fungi of almond flowers.

    Science.gov (United States)

    Schaeffer, Robert N; Vannette, Rachel L; Brittain, Claire; Williams, Neal M; Fukami, Tadashi

    2017-04-01

    Nectar mediates interactions between plants and pollinators in natural and agricultural systems. Specialized microorganisms are common nectar inhabitants, and potentially important mediators of plant-pollinator interactions. However, their diversity and role in mediating pollination services in agricultural systems are poorly characterized. Moreover, agrochemicals are commonly applied to minimize crop damage, but may present ecological consequences for non-target organisms. Assessment of ecological risk has tended to focus on beneficial macroorganisms such as pollinators, with less attention paid to microorganisms. Here, using culture-independent methods, we assess the impact of two widely-used fungicides on nectar microbial community structure in the mass-flowering crop almond (Prunus dulcis). We predicted that fungicide application would reduce fungal richness and diversity, whereas competing bacterial richness would increase, benefitting from negative effects on fungi. We found that fungicides reduced fungal richness and diversity in exposed flowers, but did not significantly affect bacterial richness, diversity, or community composition. The relative abundance of Metschnikowia OTUs, nectar specialists that can impact pollination, was reduced by both fungicides. Given growing recognition of the importance of nectar microorganisms as mediators of plant-pollinator mutualisms, future research should consider the impact of management practices on plant-associated microorganisms and consequences for pollination services in agricultural landscapes. © 2016 Society for Applied Microbiology and John Wiley & Sons Ltd.

  13. Movement of soil-applied imidacloprid and thiamethoxam into nectar and pollen of squash (Cucurbita pepo.

    Directory of Open Access Journals (Sweden)

    Kimberly A Stoner

    Full Text Available There has been recent interest in the threat to bees posed by the use of systemic insecticides. One concern is that systemic insecticides may translocate from the soil into pollen and nectar of plants, where they would be ingested by pollinators. This paper reports on the movement of two such systemic neonicotinoid insecticides, imidacloprid and thiamethoxam, into the pollen and nectar of flowers of squash (Cucurbita pepo cultivars "Multipik," "Sunray" and "Bush Delicata" when applied to soil by two methods: (1 sprayed into soil before seeding, or (2 applied through drip irrigation in a single treatment after transplant. All insecticide treatments were within labeled rates for these compounds. Pollen and nectar samples were analyzed using a standard extraction method widely used for pesticides (QuEChERS and liquid chromatography mass spectrometric analysis. The concentrations found in nectar, 10 ± 3 ppb (mean ± s.d for imidacloprid and 11 ± 6 ppb for thiamethoxam, are higher than concentrations of neonicotinoid insecticides in nectar of canola and sunflower grown from treated seed, and similar to those found in a recent study of neonicotinoids applied to pumpkins at transplant and through drip irrigation. The concentrations in pollen, 14 ± 8 ppb for imidacloprid and 12 ± 9 ppb for thiamethoxam, are higher than those found for seed treatments in most studies, but at the low end of the range found in the pumpkin study. Our concentrations fall into the range being investigated for sublethal effects on honey bees and bumble bees.

  14. The influence of flower morphology and nectar quality on the longevity of a parasitoid biological control agent

    NARCIS (Netherlands)

    Vattala, H.D.; Wratten, S.D.; Phillips, C.B.; Wäckers, F.L.

    2006-01-01

    Conservation biological control aims to enhance the efficacy of arthropod biological control agents, such as parasitoids, partly by providing them with access to floral nectar. However, the suitability of a flower species for providing nectar to a parasitoid is dependent on the morphologies of the p

  15. Chromolaena odorata (L. King & H.E. Robins (Asteraceae, an important nectar source for adult butterflies

    Directory of Open Access Journals (Sweden)

    P.V. Lakshmi

    2011-02-01

    Full Text Available Chromolaena odorata is a seasonal weed and grows like a cultivated crop. It flowers during October-December. The floral characteristics such as white to purple colour of florets, short-tubed narrow corolla with deep seated nectar, the morning anthesis and the flat-topped head inflorescence providing a standing platform are important attractants for visitation by butterflies. The florets attract butterflies of five families and sphingid hawk moths. Among the butterflies, nymphalids are diverse and visit the florets consistently; their visits effect pollination. The diurnal hawk moths, Macroglossum gyrans and Cephonodes hylas also visit the florets during dawn and dusk hours for nectar, and effect pollination. Therefore, C. odorata, being an exotic is an important nectar source for adult butterflies.

  16. Cooling Tests of the NectarCAM camera for the Cherenkov Telescope Array

    CERN Document Server

    Moulin, E; Durand, D; Feirreira, O; Fesquet, M; Giebels, B; Glicenstein, J -F; Loiseau, D; Louis, F; Nunio, F; Rateau, S; consortia, CTA

    2015-01-01

    The NectarCAM is a camera proposed for the medium-sized telescopes in the framework of the Cherenkov Telescope Array (CTA), the next-generation observatory for very-high-energy gamma-ray astronomy. The cameras are designed to operate in an open environment and their mechanics must provide protection for all their components under the conditions defined for the CTA observatory. In order to operate in a stable environment and ensure the best physics performance, each NectarCAM will be enclosed in a slightly overpressurized, nearly air-tight, camera body, to prevent dust and water from entering. The total power dissipation will be ~7.7 kW for a 1855-pixel camera. The largest fraction is dissipated by the readout electronics in the modules. We present the design and implementation of the cooling system together with the test bench results obtained on the NectarCAM thermal demonstrator.

  17. Differential volatile organic compounds in royal jelly associated with different nectar plants

    Institute of Scientific and Technical Information of China (English)

    ZHAO Ya-zhou; LI Zhi-guo; TIAN Wen-li; FANG Xiao-ming; SU Song-kun; PENG Wen-jun

    2016-01-01

    The aim of this work was to distinguish volatile organic compound (VOC) proifles of royal jely (RJ) from different nectar plants. Headspace solid-phase microextraction (HS-SPME) was used to extract VOCs from raw RJ harvested from 10 nectar plants in lfowering seasons. Qualitative and semi-quantitative analysis of VOCs extracts were performed by gas chromatography-mass spectrometry (GC-MS). Results showed that VOC proifles of RJ from the samples were rich in acid, ester and aldehyde compound classes, however, contents of them were differential, exempliifed by the data from acetic acid, benzoic acid methyl ester, hexanoic acid and octanoic acid. As a conclusion, these four VOCs can be used for distinguishing RJ harvested in the seasons of different nectar plants.

  18. Flowering biology, nectar production and insect visits in Cucurbita pepo L. flowers

    Directory of Open Access Journals (Sweden)

    Marta Dmitruk

    2012-12-01

    Full Text Available In 1998-2000 studies on length and abundance of flowering and on nectar productivity of zucchini and marrow (Cucurbita pepo L. were carried out in Lublin area. Flowers visitors were also monitored. Flowering of plants lasted from the end of June till the end of September. The mean number of flowers per plant of zucchini reached: 31 (male flowers and 26 (female flowers, and for marrow 226 and 22, respectively. Flowers lived, on average, for 5 hours. Female flowers of marrow secreted the highest amount of nectar - 1.354 g per 10 flowers, on average. Sugar content in nectar was 21.84%-27.31%. The mean total amount of sugars secreted by 10 flowers of Cucurbita pepo L. was 21.5-304.3 mg. Pollinators were mainly bumblebees and honey bees.

  19. NectarCAM, a camera for the medium sized telescopes of the Cherenkov Telescope Array

    CERN Document Server

    Glicenstein, J-F

    2016-01-01

    NectarCAM is a camera proposed for the medium-sized telescopes of the Cherenkov Telescope Array (CTA) which covers the core energy range of ~100 GeV to ~30 TeV. It has a modular design and is based on the NECTAr chip, at the heart of which is a GHz sampling Switched Capacitor Array and 12-bit Analog to Digital converter. The camera will be equipped with 265 7-photomultiplier modules, covering a field of view of 8 degrees. Each module includes photomultiplier bases, high voltage supply, pre-amplifier, trigger, readout and Ethernet transceiver. The recorded events last between a few nanoseconds and tens of nanoseconds. The expected performance of the camera are discussed. Prototypes of NectarCAM components have been built to validate the design. Preliminary results of a 19-module mini-camera are presented, as well as future plans for building and testing a full size camera.

  20. Speciose opportunistic nectar-feeding avifauna in Cuba and its association to hummingbird island biogeography

    DEFF Research Database (Denmark)

    Dalsgaard, Bo; Baquero, Andrea C.; Rahbek, Carsten

    2016-01-01

    Island organisms often have wider feeding niches than mainland organisms, and migratory birds breeding on continents often widen their niches when overwintering on islands. Cuba's low hummingbird richness has puzzled ornithologists for decades. Here, we show that the Cuban hummingbird fauna is less...... rich than expected based on Cuba's elevation, when compared to the rest of the West Indian islands. Thereafter, we report nectar-feeding behaviour by 26 non-Trochilidae bird species in Cuba, encompassing pigeons/doves, woodpeckers and passerines, and endemic, resident and migratory species. We discuss...... if Cuba's speciose non-Trochilidae nectar-feeding avifauna may be associated with its depauperate hummingbird fauna....

  1. First steps towards real-time radiography at the NECTAR facility

    Energy Technology Data Exchange (ETDEWEB)

    Buecherl, T. [Lehrstuhl fuer Radiochemie (RCM), Technische Universitaet Muenchen (TUM) (Germany)], E-mail: thomas.buecherl@radiochemie.de; Wagner, F.M. [Forschungsneutronenquelle Heinz Maier-Leibnitz (FRM II), Technische Universitaet Muenchen (Germany); Lierse von Gostomski, Ch. [Lehrstuhl fuer Radiochemie (RCM), Technische Universitaet Muenchen (TUM) (Germany)

    2009-06-21

    The beam tube SR10 at Forschungsneutronenquelle Heinz Maier-Leibnitz (FRM II) provides an intense beam of fission neutrons for medical application (MEDAPP) and for radiography and tomography of technical and other objects (NECTAR). The high neutron flux of up to 9.8E+07 cm{sup -2} s{sup -1} (depending on filters and collimation) with a mean energy of about 1.9 MeV at the sample position at the NECTAR facility prompted an experimental feasibility study to investigate the potential for real-time (RT) radiography.

  2. Holocrine secretion and cytoplasmic content of Helleborus foetidus L. (Ranunculaceae) nectar.

    Science.gov (United States)

    Vesprini, J L; Nepi, M; Ciampolini, F; Pacini, E

    2008-03-01

    We used electron microscopy to investigate the fine structure of nectary secretions of Helleborus foetidus. During the secretion period, epidermal cells of nectaries discharge the whole contents of the cytoplasm into the nectary cavity. The external wall of the cell breaks, releasing the cytoplasm as a dense aggregate that later disperses in the nectary cavity. Cell components, such as chromatin, plastids, mitochondria, lipid droplets and membranes, were found in the nectar of H. foetidus, evincing the complex nature of the secreted material. These results confirm that nectar secretion in H. foetidus is of the holocrine type.

  3. Changes in phenolics and antioxidant activity at each step of processing from pomegranate into nectar.

    Science.gov (United States)

    Surek, Ece; Nilufer-Erdil, Dilara

    2014-03-01

    Effect of all processing steps on polyphenols and antioxidant activity was investigated during an industrial scale pasteurized pomegranate nectar production, from which sampling was done at 12 steps of the process. Total phenolic (TPC), flavonoid (TFC), anthocyanin (TAC), tannin contents (TTC), antioxidant activity (TAA) (2,2'-azinobis-3-ethylbenzo-thiazoline-6-sulphonic acid diammonium salt (ABTS), cupric reducing antioxidant capacity (CUPRAC), ferric reducing ability of plasma (FRAP) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) assays), phenolic and anthocyanin profiles were analyzed in those samples. TPC, TFC, TTC and TAA were highest in whole pomegranate. For all analyses, peeling and processing into nectar resulted in significant losses, except for TAC data obtained for peeling. Losses at mashing (for TFC 24%), pressing (for TAC 13%, TTC 48%, TAA 21-63%), pasteurization (for TFC 76%, TAA 42-77%) and ultrafiltration (for TPC 18%, TFC 28%, AA 17-19%) were also significant. Pomegranate nectar, when compared with fresh edible fruit, retained 19% of TPC and 14% of TAC at the end of processing, however, as initial values were very high for pomegranate, pasteurized nectar is still a promising source of polyphenols.

  4. Presence of two types of flowers with respect to nectar sugar in two gregariously flowering species

    Indian Academy of Sciences (India)

    Chaitali Anand; Chaitrali Umranikar; Pooja Shintre; Anuja Damle; Janhavi Kale; Jahnavi Joshi; Milind Watve

    2007-06-01

    Many species of animal-pollinated flowers are known to vary widely in the nectar content of flowers. Some proportion of flowers in many species is apparently nectarless, and such flowers are believed to be ‘cheaters’. Cheating may explain a part of the variability in nectar content. If cheating exists as a qualitatively different strategy then we expect bimodality in the distribution of nectar content of flowers. It has been shown in a multispecies study that gregarious species have a higher proportion of cheater flowers. We studied the frequency distribution of total nectar sugar in two gregariously flowering species Lantana camara and Utricularia purpurascens, which differed in other floral and ecological characters. At the population level, both the species showed significant bimodality in the total sugar content of flowers. The obvious sources of heterogeneity in the data did not explain bimodality. In Lantana camara, bimodality was observed within flowers of some of the individual plants sampled. In Utricularia purpurascens the proportion of nectarless flowers was more in high-density patches, suggesting that the gregariousness hypothesis may work within a species as well. The results support the hypothesis of cheating as a distinct strategy since two distinct types of flowers were observed in both the species. The effect of density in Utricularia purpurascens also supports the gregariousness hypothesis.

  5. What shapes amino acid and sugar composition in Mediterranean floral nectars?

    NARCIS (Netherlands)

    Petanidou, T.; Van Laere, A.; Ellis, W.; Smets, E.

    2006-01-01

    We studied the amino acid (AA) composition of the floral nectars of 73 plant species occurring in a phryganic (East Mediterranean garrigue) community and investigated whether AA and sugar composition is shaped by evolutionary (plant phylogeny), ecological (flowering time as a direct effect of summer

  6. Biology of flowering and nectar production in the flowers of the beauty bush (Kolkwitzia amabilis Graebn.

    Directory of Open Access Journals (Sweden)

    Marta Dmitruk

    2012-12-01

    Full Text Available Nectar production and the morphology of the nectary and pollen grains of Kolwitzia amabilis Graebn. were studied during the period 2008–2009 and in 2011. The blooming of beauty bush flowers started in the third decade of May and ended in the middle of June; flowering lasted 22–23 days. The flower life span was 4–5 days. Nectar production began at the bud break stage. The tube of the corolla in beauty bush flowers forms a spur inside which the nectary is located. The secretory surface of the nectary consists of two layers of glandular epidermal outgrowths: unicellular trichomes, with their length ranging 54.6 μm – 70.2 μm, and papillae with a length of 13.0 μm – 20.6 μm. The mean weight of nectar per 10 flowers, determined for the three years of the study, was 8.6 mg, with a sugar concentration of 50.8%. The weight of nectar sugar was on average 4.4 mg. In terms of the size, beauty bush pollen grains are classified as medium-sized. These are tricolporate grains.

  7. Nectar accessibility determines fitness, flower choice and abundance of hoverflies that provide natural pest control

    NARCIS (Netherlands)

    van Rijn, Paul C. J.; Wäckers, Felix L.

    2016-01-01

    In modern agricultural landscapes, many organisms providing ecosystem services such as pollination and natural pest control are likely constrained by shortage of nectar and/or pollen required for adult nutrition. More and more flower-rich field margin strips and other habitats are created to elimina

  8. Nectar accessibility determines fitness, flower choice and abundance of hoverflies that provide natural pest control

    NARCIS (Netherlands)

    van Rijn, P.C.J.; Wäckers, F.L.

    2016-01-01

    1. In modern agricultural landscapes, many organisms providing ecosystem services such as pollination and natural pest control are likely constrained by shortage of nectar and/or pollen required for adult nutrition. More and more flower-rich field margin strips and other habitats are created to elim

  9. NectarCAM : a camera for the medium size telescopes of the Cherenkov Telescope Array

    CERN Document Server

    Glicenstein, J-F; Barrio, J-A; Blanch~Bigas, O; Bolmont, J; Bouyjou, F; Brun, P; Chabanne, E; Champion, C; Colonges, S; Corona, P; Delagnes, E; Delgado, C; Ginzov, C Diaz; Durand, D; Ernenwein, J-P; Fegan, S; Ferreira, O; Fesquet, M; Fiasson, A; Fontaine, G; Fouque, N; Gascon, D; Giebels, B; Henault, F; Hermel, R; Hoffmann, D; Horan, D; Houles, J; Jean, P; Jocou, L; Karkar, S; Knoedlseder, J; Kossakowski, R; Lamanna, G; LeFlour, T; Lenain, J-P; Leveque, A; Louis, F; Martinez, G; Moudden, Y; Moulin, E; Nayman, P; Nunio, F; Olive, J-F; Panazol, J-L; Pavy, S; Petrucci, P-O; Pierre, E; Prast, J; Punch, M; Ramon, P; Rateau, S; Ravel, T; Rosier-Lees, S; Sanuy, A; Shayduk, M; Sizun, P-Y; Sulanke, K-H; Tavernet, J-P; Tejedor~Alvarez, L-A; Toussenel, F; Vasileiadis, G; Voisin, V; Waegebert, V; Wischnewski, R

    2015-01-01

    NectarCAM is a camera proposed for the medium-sized telescopes of the Cherenkov Telescope Array (CTA) covering the central energy range of ~100 GeV to ~30 TeV. It has a modular design and is based on the NECTAr chip, at the heart of which is a GHz sampling Switched Capacitor Array and a 12-bit Analog to Digital converter. The camera will be equipped with 265 7-photomultiplier modules, covering a field of view of 8 degrees. Each module includes the photomultiplier bases, high voltage supply, pre-amplifier, trigger, readout and Ethernet transceiver. The recorded events last between a few nanoseconds and tens of nanoseconds. The camera trigger will be flexible so as to minimize the read-out dead-time of the NECTAr chips. NectarCAM is designed to sustain a data rate of more than 4 kHz with less than 5\\% dead time. The camera concept, the design and tests of the various subcomponents and results of thermal and electrical prototypes are presented. The design includes the mechanical structure, cooling of the electro...

  10. Consequences of toxic secondary compounds in nectar for mutualist bees and antagonist butterflies.

    Science.gov (United States)

    Jones, Patricia L; Agrawal, Anurag A

    2016-10-01

    Attraction of mutualists and defense against antagonists are critical challenges for most organisms and can be especially acute for plants with pollinating and non-pollinating flower visitors. Secondary compounds in flowers have been hypothesized to adaptively mediate attraction of mutualists and defense against antagonists, but this hypothesis has rarely been tested. The tissues of milkweeds (Asclepias spp.) contain toxic cardenolides that have long been studied as chemical defenses against herbivores. Milkweed nectar also contains cardenolides, and we have examined the impact of manipulating cardenolides in nectar on the foraging choices of two flower visitors: generalist bumble bees, Bombus impatiens, which are mutualistic pollinators, and specialist monarch butterflies, Danaus plexippus, which are herbivores as larvae and ineffective pollinators as adults. Although individual bumble bees in single foraging bouts showed no avoidance of cardenolides at the highest natural concentrations reported for milkweeds, a pattern of deterrence did arise when entire colonies were allowed to forage for several days. Monarch butterflies were not deterred by the presence of cardenolides in nectar when foraging from flowers, but laid fewer eggs on plants paired with cardenolide-laced flowers compared to controls. Thus, although deterrence of bumble bees by cardenolides may only occur after extensive foraging, a primary effect of nectar cardenolides appears to be reduction of monarch butterfly oviposition.

  11. Changes in nectar supply: A possible cause of widespread butterfly decline

    NARCIS (Netherlands)

    Wallis de Vries, M.F.; Swaay, van C.A.M.; Plate, C.L.

    2012-01-01

    Recent studies have documented declining trends of various groups of flower-visiting insects, even common butterfly species. Causes of these declines are still unclear but the loss of habitat quality across the wider countryside is thought to be a major factor. Nectar supply constitutes one of the m

  12. Nectar exploitation by herbivores and their parasitoids is a function of flower species and relative humidity

    NARCIS (Netherlands)

    Winkler, K.; Wäckers, F.L.; Kaufman, L.V.; Larraz, V.; Lenteren, van J.C.

    2009-01-01

    In conservation biological control, diversification of the agro ecosystem with flowering vegetation is seen as an important tool to support the broad range of predators and parasitoids that require nectar and pollen sources to survive and reproduce. In order to identify flowering plants that provide

  13. Drinking problems on a 'simple' diet: physiological convergence in nectar-feeding birds.

    Science.gov (United States)

    Nicolson, Susan W; Fleming, Patricia A

    2014-04-01

    Regulation of energy and water are by necessity closely linked in avian nectarivores, because the easily available sugars in nectar are accompanied by an excess of water but few electrolytes. In general, there is convergence in morphology and physiology between three main lineages of avian nectarivores that have evolved on different continents - the hummingbirds, sunbirds and honeyeaters. These birds show similar dependence of sugar preferences on nectar concentration, high intestinal sucrase activity and rapid absorption of hexoses via mediated and paracellular routes. There are differences, however, in how these lineages deal with energy challenges, as well as processing the large volumes of preformed water ingested in nectar. While hummingbirds rely on varying renal water reabsorption, the passerine nectarivores modulate intestinal water absorption during water loading, thus reducing the impact on the kidneys. Hummingbirds do not generally cope with salt loading, and have renal morphology consistent with their ability to produce copious dilute urine; by contrast, as well as being able to deal with dilute diets, honeyeaters and sunbirds are more than capable of dealing with moderately high levels of added electrolytes. And finally, in response to energy challenge, hummingbirds readily resort to torpor, while the passerines show renal and digestive responses that allow them to deal with short-term fasts and rapidly restore energy balance without using torpor. In conclusion, sunbirds and honeyeaters demonstrate a degree of physiological plasticity in dealing with digestive and renal challenges of their nectar diet, while hummingbirds appear to be more constrained by this diet.

  14. Performance of two honey bee subspecies during harsh weather and Acacia gerrardii nectar-rich flow

    Directory of Open Access Journals (Sweden)

    Awad Mohamed Awad

    Full Text Available ABSTRACT Both climatic factors and bee forage characteristics affect the population size and productivity of honey bee colonies. To our knowledge, no scientific investigation has as yet considered the potential effect of nectar-rich bee forage exposed to drastic subtropical weather conditions on the performance of honey bee colonies. This study investigated the performance of the honey bee subspecies Apis mellifera jemenitica Ruttner (Yemeni and Apis mellifera carnica Pollmann (Carniolan in weather that was hot and dry and in an environment of nectar-rich flora. The brood production, food storage, bee population and honey yield of Yemeni (native and Carniolan (imported colonies on Talh trees (Acacia gerrardii Benth., a nectar-rich, subtropical, and summer bee forage source in Central Arabia were evaluated. Owing to their structural and behavioral adaptations, the Yemeni bees constructed stronger (high population size colonies than the Carniolan bees. Although both groups yielded similar amounts of Talh honey, the Yemeni bees consumed their stored honey rapidly if not timely harvested. A. m. jemenitica has a higher performance than A. m. carnica during extremely hot-dry conditions and A. gerrardii nectar-rich flow.

  15. Alcohol discrimination and preferences in two species of nectar-feeding primate

    Science.gov (United States)

    Brown, Michael B.; Dominy, Nathaniel J.

    2016-01-01

    Recent reports suggest that dietary ethanol, or alcohol, is a supplemental source of calories for some primates. For example, slow lorises (Nycticebus coucang) consume fermented nectars with a mean alcohol concentration of 0.6% (range: 0.0–3.8%). A similar behaviour is hypothesized for aye-ayes (Daubentonia madagascariensis) based on a single point mutation (A294V) in the gene that encodes alcohol dehydrogenase class IV (ADH4), the first enzyme to catabolize alcohol during digestion. The mutation increases catalytic efficiency 40-fold and may confer a selective advantage to aye-ayes that consume the nectar of Ravenala madagascariensis. It is uncertain, however, whether alcohol exists in this nectar or whether alcohol is preferred or merely tolerated by nectarivorous primates. Here, we report the results of a multiple-choice food preference experiment with two aye-ayes and a slow loris. We conducted observer-blind trials with randomized, serial dilutions of ethanol (0–5%) in a standard array of nectar-simulating sucrose solutions. We found that both species can discriminate varying concentrations of alcohol; and further, that both species prefer the highest available concentrations. These results bolster the hypothesized adaptive function of the A294V mutation in ADH4, and a connection with fermented foods, both in aye-ayes and the last common ancestor of African apes and humans. PMID:27493777

  16. Observations on flowering plants in north central Florida that might serve as nectar sites.

    Science.gov (United States)

    Observations were made on the seasonal phenology of flowering plants along SR24 between Gainesville and Cedar Key, FL, for a period of 1 yr. The objective was to document the seasonality, species composition and relative abundance of flowering plants that might be available as nectar sites for mosq...

  17. Nectar yeasts warm the flowers of a winter-blooming plant.

    Science.gov (United States)

    Herrera, Carlos M; Pozo, María I

    2010-06-22

    Yeasts are ubiquitous in terrestrial and aquatic microbiota, yet their ecological functionality remains relatively unexplored in comparison with other micro-organisms. This paper formulates and tests the novel hypothesis that heat produced by the sugar catabolism of yeast populations inhabiting floral nectar can increase the temperature of floral nectar and, more generally, modify the within-flower thermal microenvironment. Two field experiments were designed to test this hypothesis for the winter-blooming herb Helleborus foetidus (Ranunculaceae). In experiment 1, the effect of yeasts on the within-flower thermal environment was tested by excluding them from flowers, while in experiment 2 the test involved artificial inoculation of virgin flowers with yeasts. Nectary temperature (T(nect)), within-flower air temperature (T(flow)) and external air temperature (T(air)) were measured on experimental and control flowers in both experiments. Experimental exclusion of yeasts from the nectaries significantly reduced, and experimental addition of yeasts significantly increased, the temperature excess of nectaries (DeltaT(nect) = T(nect) - T(air)) and the air space inside flowers in relation to the air just outside the flowers. In non-experimental flowers exposed to natural pollinator visitation, DeltaT(nect) was linearly related to log yeast cell density in nectar, and reached +6 degrees C in nectaries with the densest yeast populations. The warming effect of nectar-dwelling yeasts documented in this study suggests novel ecological mechanisms potentially linking nectarivorous microbes with winter-blooming plants and their insect pollinators.

  18. Nectar robbing, forager efficiency and seed set: Bumblebees foraging on the self incompatible plant Linaria vulgaris (Scrophulariaceae)

    Science.gov (United States)

    Stout, Jane C.; Allen, John A.; Goulson, Dave

    2000-07-01

    In southern England, Linaria vulgaris (common yellow toadflax) suffers from high rates of nectar robbery by bumblebees. In a wild population of L. vulgaris we found that 96 % of open flowers were robbed. Five species of bumblebee were observed foraging on these flowers, although short-tongued species ( Bombus lapidarius, B. lucorum and B. terrestris) robbed nectar whilst longer-tongued ones behaved as legitimate pollinators ( B. hortorum and B. pascuorum). Nectar rewards were highly variable; on average there was less nectar in robbed than in unrobbed flowers, but this difference was not statistically significant. The proportion of flowers containing no nectar was significantly higher for robbed flowers compared with unrobbed flowers. Secondary robbers and legitimate pollinators had similar handling times on flowers and, assuming they select flowers at random to forage on, received approximately the same nectar profit per minute, largely because most flowers had been robbed. There was no significant difference in the number of seeds in pods of robbed flowers and in pods of flowers that were artificially protected against robbing. However, more of the robbed flowers set at least some seed than the unrobbed flowers, possibly as a consequence of the experimental manipulation. We suggest that nectar robbing has little effect on plant fecundity because legitimate foragers are present in the population, and that seed predation and seed abortion after fertilization may be more important factors in limiting seed production in this species.

  19. Composition, richness and nonrandom assembly of culturable bacterial-microfungal communities in floral nectar of Mediterranean plants.

    Science.gov (United States)

    Alvarez-Pérez, Sergio; Herrera, Carlos M

    2013-03-01

    The recent upsurge of interest in the role of floral nectar as a habitat for microorganisms has led to some detailed analyses of nectarivorous yeasts. In contrast, very little is known on the occurrence and diversity of nectar-dwelling bacteria, and bacterial-fungal interactions within nectar remain unexplored. In this work, we studied both the culturable bacteria and microfungi found in the floral nectar of wild Mediterranean plants. In general, bacteria and yeasts were found coexisting in nectar more often than would be expected by chance, and such positive association persisted after accounting for phylogenetic nonindependence of the plant species surveyed. Metschnikowia species were confirmed as the main fungal components of nectar communities, and Acinetobacter was identified as the main bacterial taxa. Finally, individual Operational Taxonomic Units (OTUs) were found to co-occur less frequently than predicted by random expectations. There existed, however, some pairwise associations between OTUs that seemed to account for the general pattern of positive bacteria-yeasts coexistence. We conclude that the culturable communities of nectar microorganisms associated with wild Mediterranean plants are nonrandom assemblages of bacterial and yeast species. © 2012 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

  20. Nectar secretion dynamic links pollinator behavior to consequences for plant reproductive success in the ornithophilous mistletoe Psittacanthus robustus.

    Science.gov (United States)

    Guerra, T J; Galetto, L; Silva, W R

    2014-09-01

    The mistletoe Psittacanthus robustus was studied as a model to link flower phenology and nectar secretion strategy to pollinator behaviour and the reproductive consequences for the plant. The bright-coloured flowers presented diurnal anthesis, opened asynchronously throughout the rainy season and produced copious dilute nectar as the main reward for pollinators. Most nectar was secreted just after flower opening, with little sugar replenishment after experimental removals. During the second day of anthesis in bagged flowers, the flowers quickly reabsorbed the offered nectar. Low values of nectar standing crop recorded in open flowers can be linked with high visitation rates by bird pollinators. Eight hummingbirds and two passerines were observed as potential pollinators. The most frequent flower visitors were the hummingbirds Eupetomena macroura and Colibri serrirostris, which actively defended flowering mistletoes. The spatial separation between anthers, stigma and nectar chamber promotes pollen deposition on flapping wings of hovering hummingbirds that usually probe many flowers per visit. Seed set did not differ between hand-, self- and cross-pollinated flowers, but these treatments set significantly more seeds than flowers naturally exposed to flower visitors. We suggest that the limitation observed in the reproductive success of this plant is not related to pollinator scarcity, but probably to the extreme frequency of visitation by territorial hummingbirds. We conclude that the costs and benefits of plant reproduction depend on the interaction strength between flowers and pollinators, and the assessment of nectar secretion dynamics, pollinator behaviour and plant breeding system allows clarification of the complexity of such associations.

  1. Sensory acceptance of mixed nectar of papaya, passion fruit and acerola

    Directory of Open Access Journals (Sweden)

    Matsuura Fernando César Akira Urbano

    2004-01-01

    Full Text Available Nectars are beverages formulated with the juice or pulp of one or more fruits, plus water and sugar in concentrations resulting in a "ready-to-drink" product. Recently, the market for such products has greatly expanded. Fruit mixtures present a series of advantages, such as the combination of different aromas and flavors and the sum of their nutritional components. The objective of this work was to develop a nectar based on papaya pulp and passion fruit juice, enriched with the vitamin C present in acerola pulp, optimizing the formulation using sensory consumer tests and a response surface statistical methodology. Eleven formulations were prepared using different concentrations of papaya pulp and passion fruit juice and sucrose, and maintaining the concentration of acerola pulp constant. The sensory tests were carried out with 22 non-trained panelists using a structured 9-point hedonic scale to evaluate overall acceptance. The acceptance means were submitted to regression analysis, by first calculating a polynomial quadratic equation. A predictive model was adjusted considering only those parameters where P < 0.05, and a response surface was generated. The overall acceptance of nectars of different formulations varied from 5 ("neither liked nor disliked" to more than 7 ("liked moderately", showing that some products can be considered adequate to consumers, like the nectar produced with 37.5% papaya pulp, 7.5% passion fruit juice, and 5.0% acerola pulp, added of 15% sucrose. A quadratic predictive overall acceptance model, with a regression coefficient of 0.97 was obtained. The sensory acceptance of nectars was positively affected by increases in the concentrations of papaya pulp and of sucrose. Thus, some products presented good sensory acceptance suggesting commercial potential.

  2. Variation in the outcomes of an ant-plant system: fire and leaf fungus infection reduce benefits to plants with extrafloral nectaries.

    Science.gov (United States)

    Pires, L P; Del-Claro, K

    2014-01-01

    Interactions between species are evolutionary malleable and may suffer changes in small timescales. Environmental disturbances, such as fire, can deeply affect species interactions, but how they influence the outcome of a mutualistic interaction has yet to be studied. In order to test the hypothesis that an environmental disturbance, in this case fire, may produce differences in the outcome of the association of ants with the extrafloral-nectaries-bearing plant Qualea multiflora Mart. (Myrtales: Vochysiaceae), a previous study was replicated, but this time after fire incidence, at the same study site and with the same plant species. Eight ant species visited Q. multiflora, and the most abundant genera were Crematogaster, Cephalotes, and Camponotus. Herbivores were found in branches with and without ants with no statistical difference, but foliar herbivory was always higher in branchs where ants were absent. Leaves were infested by fungi, and fungi spots were higher in branches where ants were present. Compared to the previous study, it was clearly observed that ant benefits to Q. multiflora varied over time. The most common ant species still protected leaves against chewing herbivores, but a new kind of leaf damage appeared, namely fungi spots. Data also support that ants may be acting as vectors of fungi spores on plants, as ant visited branches had higher fungus incidence than non-visited branches. Fire is a major source of disturbance in tropical savannas, and we suggest that it can cause strong variation in the outcomes of interactions between ants and plants with extrafloral nectaries in the Brazilian tropical savanna. This is an open access paper. We use the Creative Commons Attribution 3.0 license that permits unrestricted use, provided that the paper is properly attributed.

  3. Food for Pollinators: Quantifying the Nectar and Pollen Resources of Urban Flower Meadows.

    Science.gov (United States)

    Hicks, Damien M; Ouvrard, Pierre; Baldock, Katherine C R; Baude, Mathilde; Goddard, Mark A; Kunin, William E; Mitschunas, Nadine; Memmott, Jane; Morse, Helen; Nikolitsi, Maria; Osgathorpe, Lynne M; Potts, Simon G; Robertson, Kirsty M; Scott, Anna V; Sinclair, Frazer; Westbury, Duncan B; Stone, Graham N

    2016-01-01

    Planted meadows are increasingly used to improve the biodiversity and aesthetic amenity value of urban areas. Although many 'pollinator-friendly' seed mixes are available, the floral resources these provide to flower-visiting insects, and how these change through time, are largely unknown. Such data are necessary to compare the resources provided by alternative meadow seed mixes to each other and to other flowering habitats. We used quantitative surveys of over 2 million flowers to estimate the nectar and pollen resources offered by two exemplar commercial seed mixes (one annual, one perennial) and associated weeds grown as 300m2 meadows across four UK cities, sampled at six time points between May and September 2013. Nectar sugar and pollen rewards per flower varied widely across 65 species surveyed, with native British weed species (including dandelion, Taraxacum agg.) contributing the top five nectar producers and two of the top ten pollen producers. Seed mix species yielding the highest rewards per flower included Leontodon hispidus, Centaurea cyanus and C. nigra for nectar, and Papaver rhoeas, Eschscholzia californica and Malva moschata for pollen. Perennial meadows produced up to 20x more nectar and up to 6x more pollen than annual meadows, which in turn produced far more than amenity grassland controls. Perennial meadows produced resources earlier in the year than annual meadows, but both seed mixes delivered very low resource levels early in the year and these were provided almost entirely by native weeds. Pollen volume per flower is well predicted statistically by floral morphology, and nectar sugar mass and pollen volume per unit area are correlated with flower counts, raising the possibility that resource levels can be estimated for species or habitats where they cannot be measured directly. Our approach does not incorporate resource quality information (for example, pollen protein or essential amino acid content), but can easily do so when suitable data

  4. Food for Pollinators: Quantifying the Nectar and Pollen Resources of Urban Flower Meadows.

    Directory of Open Access Journals (Sweden)

    Damien M Hicks

    Full Text Available Planted meadows are increasingly used to improve the biodiversity and aesthetic amenity value of urban areas. Although many 'pollinator-friendly' seed mixes are available, the floral resources these provide to flower-visiting insects, and how these change through time, are largely unknown. Such data are necessary to compare the resources provided by alternative meadow seed mixes to each other and to other flowering habitats. We used quantitative surveys of over 2 million flowers to estimate the nectar and pollen resources offered by two exemplar commercial seed mixes (one annual, one perennial and associated weeds grown as 300m2 meadows across four UK cities, sampled at six time points between May and September 2013. Nectar sugar and pollen rewards per flower varied widely across 65 species surveyed, with native British weed species (including dandelion, Taraxacum agg. contributing the top five nectar producers and two of the top ten pollen producers. Seed mix species yielding the highest rewards per flower included Leontodon hispidus, Centaurea cyanus and C. nigra for nectar, and Papaver rhoeas, Eschscholzia californica and Malva moschata for pollen. Perennial meadows produced up to 20x more nectar and up to 6x more pollen than annual meadows, which in turn produced far more than amenity grassland controls. Perennial meadows produced resources earlier in the year than annual meadows, but both seed mixes delivered very low resource levels early in the year and these were provided almost entirely by native weeds. Pollen volume per flower is well predicted statistically by floral morphology, and nectar sugar mass and pollen volume per unit area are correlated with flower counts, raising the possibility that resource levels can be estimated for species or habitats where they cannot be measured directly. Our approach does not incorporate resource quality information (for example, pollen protein or essential amino acid content, but can easily do so

  5. Honey bees avoid nectar colonized by three bacterial species, but not by a yeast species, isolated from the bee gut.

    Directory of Open Access Journals (Sweden)

    Ashley P Good

    Full Text Available The gut microflora of the honey bee, Apis mellifera, is receiving increasing attention as a potential determinant of the bees' health and their efficacy as pollinators. Studies have focused primarily on the microbial taxa that appear numerically dominant in the bee gut, with the assumption that the dominant status suggests their potential importance to the bees' health. However, numerically minor taxa might also influence the bees' efficacy as pollinators, particularly if they are not only present in the gut, but also capable of growing in floral nectar and altering its chemical properties. Nonetheless, it is not well understood whether honey bees have any feeding preference for or against nectar colonized by specific microbial species. To test whether bees exhibit a preference, we conducted a series of field experiments at an apiary using synthetic nectar inoculated with specific species of bacteria or yeast that had been isolated from the bee gut, but are considered minor components of the gut microflora. These species had also been found in floral nectar. Our results indicated that honey bees avoided nectar colonized by the bacteria Asaia astilbes, Erwinia tasmaniensis, and Lactobacillus kunkeei, whereas the yeast Metschnikowia reukaufii did not affect the feeding preference of the insects. Our results also indicated that avoidance of bacteria-colonized nectar was caused not by the presence of the bacteria per se, but by the chemical changes to nectar made by the bacteria. These findings suggest that gut microbes may not only affect the bees' health as symbionts, but that some of the microbes may possibly affect the efficacy of A. mellifera as pollinators by altering nectar chemistry and influencing their foraging behavior.

  6. Comparative effects of two species of floricolous Metschnikowia yeasts on nectar

    Directory of Open Access Journals (Sweden)

    Canto, Azucena

    2015-06-01

    Full Text Available Nectar yeast communities in southern Spain are dominated by two closely-related species, Metschnikowia reukaufii Pitt & M.W. Mill. and M. gruessii Gim.-Jurado (Ascomycota, Saccharomycetales, although they tend to be distributed differentially across different host plants. We explore here the possibility that the two yeasts play different functional roles in floral nectar by differing in their impact on sugar concentration and composition of nectar. Experiments were undertaken under controlled conditions using bumblebees caught foraging on the flowers of two different host plants each of which is known to harbor predominantly one of the two yeasts. Bumblebees were used as sources of inocula to obtain two groups of samples from the nectar of Helleborus foetidus L. (Ranunculaceae: nectar samples inoculated with M. gruessii and samples inoculated with M. reukaufii. Metschnikowia gruessii was poorly represented in nectar samples, while M. reukaufii was by far the most common and had the highest cell density. Although the two yeasts caused relatively similar changes in nectar sugar composition, which involved increasing fructose and decreasing sucrose proportions, they marginally differed in their quantitative impact on total nectar sugar concentration. Results suggest that differential yeast occurrence across host plants may lead to yeast specialization and modify the outcomes of the plant-pollinator interface.Las comunidades de levaduras asociadas al néctar en el sur de España son dominadas por dos especies, Metschnikowia reukaufii Pitt & M.W. Mill. y M. gruessii Gim.-Jurado (Ascomycota, Saccharomycetales. Ambas levaduras son especies muy cercanas entre sí, pero se distribuyen diferencialmente entre las especies de plantas cuyo néctar las hospeda. En este trabajo se explora la posibilidad de que las levaduras tengan funciones distintas impactando diferencialmente la concentración y composición del néctar. Para esto se realizaron experimentos

  7. Relationship between spatial working memory performance and diet specialization in two sympatric nectar bats.

    Directory of Open Access Journals (Sweden)

    Mickaël Henry

    Full Text Available Behavioural ecologists increasingly recognise spatial memory as one the most influential cognitive traits involved in evolutionary processes. In particular, spatial working memory (SWM, i.e. the ability of animals to store temporarily useful information for current foraging tasks, determines the foraging efficiency of individuals. As a consequence, SWM also has the potential to influence competitive abilities and to affect patterns of sympatric occurrence among closely related species. The present study aims at comparing the efficiency of SWM between generalist (Glossophaga soricina and specialist (Leptonycteris yerbabuenae nectarivorous bats at flowering patches. The two species differ in diet--the generalist diet including seasonally fruits and insects with nectar and pollen while the specialist diet is dominated by nectar and pollen yearlong--and in some morphological traits--the specialist being heavier and with proportionally longer rostrum than the generalist. These bats are found sympatrically within part of their range in the Neotropics. We habituated captive individuals to feed on artificial flower patches and we used infrared video recordings to monitor their ability to remember and avoid the spatial location of flowers they emptied in previous visits in the course of 15-min foraging sequences. Experiments revealed that both species rely on SWM as their foraging success attained significantly greater values than random expectations. However, the nectar specialist L. yerbabuenae was significantly more efficient at extracting nectar (+28% in foraging success, and sustained longer foraging bouts (+27% in length of efficient foraging sequences than the generalist G. soricina. These contrasting SWM performances are discussed in relation to diet specialization and other life history traits.

  8. Relationship between Spatial Working Memory Performance and Diet Specialization in Two Sympatric Nectar Bats

    Science.gov (United States)

    Henry, Mickaël; Stoner, Kathryn E.

    2011-01-01

    Behavioural ecologists increasingly recognise spatial memory as one the most influential cognitive traits involved in evolutionary processes. In particular, spatial working memory (SWM), i.e. the ability of animals to store temporarily useful information for current foraging tasks, determines the foraging efficiency of individuals. As a consequence, SWM also has the potential to influence competitive abilities and to affect patterns of sympatric occurrence among closely related species. The present study aims at comparing the efficiency of SWM between generalist (Glossophaga soricina) and specialist (Leptonycteris yerbabuenae) nectarivorous bats at flowering patches. The two species differ in diet – the generalist diet including seasonally fruits and insects with nectar and pollen while the specialist diet is dominated by nectar and pollen yearlong – and in some morphological traits – the specialist being heavier and with proportionally longer rostrum than the generalist. These bats are found sympatrically within part of their range in the Neotropics. We habituated captive individuals to feed on artificial flower patches and we used infrared video recordings to monitor their ability to remember and avoid the spatial location of flowers they emptied in previous visits in the course of 15-min foraging sequences. Experiments revealed that both species rely on SWM as their foraging success attained significantly greater values than random expectations. However, the nectar specialist L. yerbabuenae was significantly more efficient at extracting nectar (+28% in foraging success), and sustained longer foraging bouts (+27% in length of efficient foraging sequences) than the generalist G. soricina. These contrasting SWM performances are discussed in relation to diet specialization and other life history traits. PMID:21931612

  9. [Microbiological and physicochemical evaluation of pasteurized nectar elaborated with tree tomato (Cyphomandra betaceae Sendth)pulp].

    Science.gov (United States)

    Moreno Alvarez, Mario José; Girán, Nathaly; Serrano, Karla; García, David; Belén Camacho, Douglas R

    2003-09-01

    Tree tomato (Cyphomandra betaceae Sendth) is a species from high tropical regions. In Venezuela, it is cultivate at the Andean and Aragua state but its consumption is restricted as fruit-fresh, though it a nutritious and industrial potential due its provitamin A content. In this research four nectars were elaborated in proportion I L pulp/4 L of water (1:4) and addition of ascorbic acid (I: 0%; II: 0.5%; III: 1.0 y IV: 1.5%). The nectars were pasteurized (60 degrees C for 30 min), tuned into amber bottle, and stored under refrigeration conditions (7.0 +/- 1.0 degrees C). Weekly during 21 days the mesophilic bacteria, molds, yeasts, total coliforms (MPN/mL), pH, degree Brix, acidity, total carotenoids, vitamin C and total sugars were evaluated. The mesophilic bacteria content was 0.05) were founded on: pH. degree Brix and total sugars. Significant differences (P < 0.05) were founded in vitamin C and total carotenoids content. Sensorial analysis did not show significant differences between formulations for the smell and flavor attributes, when the color was discriminate during the evaluations. The formulation I (without acid ascorbic) had more preference due its color. In conclusion, the nectars showed useful life of 14-21 days under refrigeration condition storage due to the adequate physicochemical and microbiological quality of the product.

  10. Butterfly diversity in relation to nectar food plants from Bhor Tahsil, Pune District, Maharashtra, India

    Directory of Open Access Journals (Sweden)

    R.K. Nimbalkar

    2011-03-01

    Full Text Available Floral attributes are well known to influence nectar feeding butterflies. However, there is paucity of information on food resources of adult butterflies as compared to that of larvae. The present study was carried out from Bhor Tahsil of Pune District, Maharashtra, India, during August 2007 to August 2009. A total of 64 butterfly species were recorded. Family Nymphalidae dominates in the study area, followed by Lycaenidae, Pieridae, Hesperiidae and Papilionidae. Nineteen nectar food plants were identified belonging to 10 plant families. Plants of the Asteraceae family are more used by butterflies as nectar food plants. Visits of butterflies were more frequent to flowers with tubular corollas than to non-tubular ones, to flowers coloured red, yellow, blue and purple than those coloured white and pink and to flower sources available for longer periods in the year. Species abundance reached the peak in the months during August to November. A decline in species abundance was observed from the months December to January and continued up to the end of May. Our findings are important with respect to monitoring butterfly and plant diversity and defining conservation strategies in the Bhor Tahsil.

  11. Sugar concentration in nectar: a quantitative metric of crop attractiveness for refined pollinator risk assessments.

    Science.gov (United States)

    Knopper, Loren D; Dan, Tereza; Reisig, Dominic D; Johnson, Josephine D; Bowers, Lisa M

    2016-10-01

    Those involved with pollinator risk assessment know that agricultural crops vary in attractiveness to bees. Intuitively, this means that exposure to agricultural pesticides is likely greatest for attractive plants and lowest for unattractive plants. While crop attractiveness in the risk assessment process has been qualitatively remarked on by some authorities, absent is direction on how to refine the process with quantitative metrics of attractiveness. At a high level, attractiveness of crops to bees appears to depend on several key variables, including but not limited to: floral, olfactory, visual and tactile cues; seasonal availability; physical and behavioral characteristics of the bee; plant and nectar rewards. Notwithstanding the complexities and interactions among these variables, sugar content in nectar stands out as a suitable quantitative metric by which to refine pollinator risk assessments for attractiveness. Provided herein is a proposed way to use sugar nectar concentration to adjust the exposure parameter (with what is called a crop attractiveness factor) in the calculation of risk quotients in order to derive crop-specific tier I assessments. This Perspective is meant to invite discussion on incorporating such changes in the risk assessment process. © 2016 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. © 2016 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

  12. Knockdown of MYB305 disrupts nectary starch metabolism and floral nectar production.

    Science.gov (United States)

    Liu, Guangyu; Thornburg, Robert W

    2012-05-01

    MYB transcription factors have important roles during floral organ development. In this study, we generated myb305 RNAi knockdown tobacco plants and studied the role of MYB305 in the growth of the floral nectary. We have previously shown the MYB305 regulates the expression of flavonoid metabolic genes as well as of nectar proteins (nectarins); however, the myb305 plants showed other floral phenotypes that we investigate in these studies. The nectaries of myb305 plants show juvenile character at late stages of development and secrete reduced levels of nectar. Because starch metabolism is intimately involved in nectar secretion and is strongly regulated during normal nectary development, we examined the accumulation of starch in the nectaries of the myb305 plants. The myb305 plants accumulated lower levels of starch in their nectaries than did wild-type plants. The reduced starch correlated with the reduced expression of the ATP-glucose pyrophosphorylase (small subunit) gene in nectaries of the myb305 plants during the starch biosynthetic phase. Expression of genes encoding several starch-degrading enzymes including β-amylase, isoamylase 3, and α-amylase was also reduced in the myb305 plants. In addition to regulating nectarin and flavonoid metabolic gene expression, these results suggest that MYB305 may also function in the tobacco nectary maturation program by controlling the expression of starch metabolic genes.

  13. Nectar profitability, not empty honey stores, stimulate recruitment and foraging in Melipona scutellaris (Apidae, Meliponini).

    Science.gov (United States)

    Schorkopf, Dirk Louis P; de Sá Filho, Geovan Figueirêdo; Maia-Silva, Camila; Schorkopf, Martina; Hrncir, Michael; Barth, Friedrich G

    2016-10-01

    In stingless bees (Meliponini) like in many other eusocial insect colonies food hoarding plays an important role in colony survival. However, very little is known on how Meliponini, a taxon restricted to tropical and subtropical regions, respond to different store conditions. We studied the impact of honey removal on nectar foraging activity and recruitment behaviour in Melipona scutellaris and compared our results with studies of the honey bee Apis mellifera. As expected, foraging activity increased significantly during abundance of artificial nectar and when increasing its profitability. Foraging activity on colony level could thereby frequently increase by an order of magnitude. Intriguingly, however, poor honey store conditions did not induce increased nectar foraging or recruitment activity. We discuss possible reasons explaining why increasing recruitment and foraging activity are not used by meliponines to compensate for poor food conditions in the nest. Among these are meliponine specific adaptations to climatic and environmental conditions, as well as physiology and brood rearing, such as mass provisioning of the brood.

  14. Sensory profile and drivers of liking for grape nectar among smoker and nonsmoker consumers

    Directory of Open Access Journals (Sweden)

    Cristiane Ramos Voorpostel

    2014-03-01

    Full Text Available Decreased gustatory and olfactory capacity is one of the problems caused by tobacco use. The objectives of this study were to determine the sensory profile of six grape nectar samples sweetened with different sweeteners and to verify the drivers of liking in two distinct consumer groups: smokers and nonsmokers. The sensory profile was constructed by twelve trained panelists using quantitative descriptive analysis (QDA. Consumer tests were performed with 112 smokers and 112 nonsmokers. Partial least squares regression analyses was used to identify the drivers of acceptance and rejection of the grape nectars among the two consumer groups. According to the QDA, the samples differed regarding six of the nineteen attributes generated. The absolute averages of the affective test were lower in the group of smokers; possibly because smoking influences acceptance and eating preferences, especially with regard to sweet foods. The results showed that the grape flavor was the major driver of preference for acceptance of the nectar, while astringency, wine aroma, bitterness and sweetness, and bitter aftertaste were drivers of rejection in the two groups of consumers, with some differences between the groups.

  15. Characteristics of blooming, floral nectaries and nectar of Malus sargentii Rehd.

    Directory of Open Access Journals (Sweden)

    Elżbieta Weryszko-Chmielewska

    2012-12-01

    Full Text Available In the years 2007-2008, the flowering biology of Malus sargentii, an ornamental apple tree native to Japan, was studied in the conditions of Lublin (Poland. The daily rate of flower opening, flowering duration and flower visitation by insects were determined. The amount of nectar produced per flower and sugar content in the nectar were investigated. The size of nectaries and the micromorphology of their surface were examined using light and scanning electron microscopy. It was found that the greatest amount of flowers opened between 11.00 and 13.00. During this time, the largest number of insects was observed in the flowers. Bees (90% were predominant among the insects, with a much smaller number of bumblebees (6% and butterflies (4%. The flower life span was 5 days. Over this period, the flower produced, on the average, 0.71 mg of nectar with an average sugar content of 32%. The nectaries of Malus sargentii are orange-yellow coloured and they represent the hypanthial type. Due to the protrusion of the nectariferous tissue, they are classified as automorphic nectaries. The surface of the epidermal cells of the nectary was distinguished by distinct cuticle folds. A small number of stomata were located only in the basal part of the nectary. At the beginning of flowering, all stomata were closed, but secretion traces were observed near well-developed outer cuticular ledges.

  16. Ecosystem-Based Incorporation of Nectar-Producing Plants for Stink Bug Parasitoids

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    Glynn Tillman

    2017-06-01

    Full Text Available Adult parasitoids of pest insects rely on floral resources for survival and reproduction, but can be food-deprived in intensively managed agricultural systems lacking these resources. Stink bugs are serious pests for crops in southwest Georgia. Provisioning nectar-producing plants for parasitoids of stink bugs potentially can enhance biocontrol of these pests. Knowledge of spatial and temporal availability and distribution of stink bugs in host plants is necessary for appropriate timing and placement of flowering plants in agroecosystems. Stink bugs move between closely associated host plants throughout the growing season in response to deteriorating suitability of their host plants. In peanut-cotton farmscapes, stink bugs develop in peanut, and subsequently the adults disperse into adjacent cotton. Parasitism of Nezara viridula (L. adults by Trichopoda pennipes (F. at the peanut-cotton interface was significantly higher in cotton with a strip of milkweed or buckwheat between the two crops than in cotton alone. Milkweed and buckwheat also provided nectar to a wide range of insect pollinators. Monarch butterflies fed on milkweed. When placed between peanut and cotton, a strip of soybean was an effective trap crop for cotton, reducing economic damage. Incorporation of buckwheat near soybean enhanced parasitism of Euschistus servus (Say eggs by Telenomus podisi Ashmead in cotton. In conclusion, nectar provision enhances biocontrol of stink bugs, acts together with other management tactics for stink bug control, and aids in conservation of natural enemies, insect pollinators, and the monarch butterfly.

  17. Ecosystem-Based Incorporation of Nectar-Producing Plants for Stink Bug Parasitoids.

    Science.gov (United States)

    Tillman, Glynn

    2017-06-24

    Adult parasitoids of pest insects rely on floral resources for survival and reproduction, but can be food-deprived in intensively managed agricultural systems lacking these resources. Stink bugs are serious pests for crops in southwest Georgia. Provisioning nectar-producing plants for parasitoids of stink bugs potentially can enhance biocontrol of these pests. Knowledge of spatial and temporal availability and distribution of stink bugs in host plants is necessary for appropriate timing and placement of flowering plants in agroecosystems. Stink bugs move between closely associated host plants throughout the growing season in response to deteriorating suitability of their host plants. In peanut-cotton farmscapes, stink bugs develop in peanut, and subsequently the adults disperse into adjacent cotton. Parasitism of Nezara viridula (L.) adults by Trichopoda pennipes (F.) at the peanut-cotton interface was significantly higher in cotton with a strip of milkweed or buckwheat between the two crops than in cotton alone. Milkweed and buckwheat also provided nectar to a wide range of insect pollinators. Monarch butterflies fed on milkweed. When placed between peanut and cotton, a strip of soybean was an effective trap crop for cotton, reducing economic damage. Incorporation of buckwheat near soybean enhanced parasitism of Euschistus servus (Say) eggs by Telenomus podisi Ashmead in cotton. In conclusion, nectar provision enhances biocontrol of stink bugs, acts together with other management tactics for stink bug control, and aids in conservation of natural enemies, insect pollinators, and the monarch butterfly.

  18. Risk assessment of additives through soft drinks and nectars consumption on Portuguese population: a 2010 survey.

    Science.gov (United States)

    Diogo, Janina S G; Silva, Liliana S O; Pena, Angelina; Lino, Celeste M

    2013-12-01

    This study investigated whether the Portuguese population is at risk of exceeding ADI levels for acesulfame-K, saccharin, aspartame, caffeine, benzoic and sorbic acid through an assessment of dietary intake of additives and specific consumption of four types of beverages, traditional soft drinks and soft drinks based on mineral waters, energetic drinks, and nectars. The highest mean levels of additives were found for caffeine in energetic drinks, 293.5mg/L, for saccharin in traditional soft drinks, 18.4 mg/L, for acesulfame-K and aspartame in nectars, with 88.2 and 97.8 mg/L, respectively, for benzoic acid in traditional soft drinks, 125.7 mg/L, and for sorbic acid in soft drinks based on mineral water, 166.5 mg/L. Traditional soft drinks presented the highest acceptable daily intake percentages (ADIs%) for acesulfame-K, aspartame, benzoic and sorbic acid and similar value for saccharin (0.5%) when compared with soft drinks based on mineral water, 0.7%, 0.08%, 7.3%, and 1.92% versus 0.2%, 0.053%, 0.6%, and 0.28%, respectively. However for saccharin the highest percentage of ADI was obtained for nectars, 0.9%, in comparison with both types of soft drinks, 0.5%. Therefore, it is concluded that the Portuguese population is not at risk of exceeding the established ADIs for the studied additives.

  19. The location of nectaries and nectar secretion in the flowers of Allium giganteum Regel

    Directory of Open Access Journals (Sweden)

    Beata Żuraw

    2012-12-01

    Full Text Available In the flowers of Allium there are found septal nectaries; in particular species, their outlet can be located in different parts of the ovary. The inflorescences of these plants are a rich source of nectar for insects. The location and structure of septal nectaries in the flowers of Allium giganteum Regel were investigated. Light and scanning electron microscopy was used. The septal nectaries were found to be located in the lower part of the ovary and in the gynophore on which the ovary is borne. Nectar is secreted into the nectary slits from which it flows through the ducts to three openings located in the upper part of the gynophore, from whence it gets outside in the vicinity of the expanded parts of the filaments. Sugar concentration in the nectar of A. giganteum averaged 54.5%, while sugar weight per flower was determined to be 0.36 mg. When converted into sugar weight per inflorescence, numbering more than 2,000 flowers, it was 771.7 mg.

  20. Influence of Continuous Drought on Nectar Secreting of Nectar Plant and Optimization of Bee Breeding Technology%持续干旱对蜜源植物泌蜜的影响及养蜂技术优化研究

    Institute of Scientific and Technical Information of China (English)

    余玉生; 张学文; 卢焕仙; 张祖芸; 赵洪木; 夏培康

    2013-01-01

    In order to understand the influence of three years continuous drought on flowering and nectar secreting of nectar plant, corresponding bee breeding technologies were adopted to improve economic benefits of beekeeping.From July 2009 to June 2012, a tracking survey was conducted to six kinds of nectar plant (common vetch, pomegranates, lobular eucalyptus, wild ageratum, loquat and Elsholtzia rugulosa Hemsl), and then the situations of flowering and nectar secreting of each nectar plant during three years were compared.According to the comparison results, corresponding breeding technologies for bee were chosen.The results showed that flowering and nectar secreting of major nectar plants were influenced greatly by continuous drought, but complementary nectar plants secreted nectar relatively good for suitable temperature and no heavy rain and wind.Therefore, if adopting corresponding breeding technologies in continuous drought years, it also can obtain a good economic benefit.%为了了解云南省持续3年干旱对蜜源植物开花流蜜的影响,采取相应的蜜蜂饲养技术提高养蜂经济效益.2009年7月~2012年6月对苕子、石榴、小叶桉树、野藿香、枇杷、野坝子6种蜜源植物进行跟踪调查,对比每一种蜜源植物3年开花流蜜情况,并对蜜蜂采取相应的饲养管理技术.结果表明:主要蜜源植物开花泌蜜受到很大的影响,辅助蜜源植物反而因温度适合,没有大雨或大风的影响而流蜜相对较好.这说明在持续干旱年份只要采取相应的饲养技术,即可获得很好的经济效益.

  1. Nectar sugars and amino acids in day- and night-flowering Nicotiana species are more strongly shaped by pollinators’ preferences than organic acids and inorganic ions

    Science.gov (United States)

    Tiedge, Kira; Lohaus, Gertrud

    2017-01-01

    Floral nectar contains mainly sugars but also amino acids, organic acids, inorganic ions and secondary compounds to attract pollinators. The genus Nicotiana exhibits great diversity among species in floral morphology, flowering time, nectar compositions, and predominant pollinators. We studied nectar samples of 20 Nicotiana species, composed equally of day- and night-flowering plants and attracting different groups of pollinators (e.g. hummingbirds, moths or bats) to investigate whether sugars, amino acids, organic acids and inorganic ions are influenced by pollinator preferences. Glucose, fructose and sucrose were the only sugars found in the nectar of all examined species. Sugar concentration of the nectar of day-flowering species was 20% higher and amino acid concentration was 2-3-fold higher compared to the nectar of night-flowering species. The sucrose-to-hexose ratio was significantly higher in night-flowering species and the relative share of sucrose based on the total sugar correlated with the flower tube length in the nocturnal species. Flowers of different tobacco species contained varying volumes of nectar which led to about 150-fold higher amounts of total sugar per flower in bat- or sunbird-pollinated species than in bee-pollinated or autogamous species. This difference was even higher for total amino acids per flower (up to 1000-fold). As a consequence, some Nicotiana species invest large amounts of organic nitrogen for certain pollinators. Higher concentrations of inorganic ions, predominantly anions, were found in nectar of night-flowering species. Therefore, higher anion concentrations were also associated with pollinator types active at night. Malate, the main organic acid, was present in all nectar samples but the concentration was not correlated with pollinator type. In conclusion, statistical analyses revealed that pollinator types have a stronger effect on nectar composition than phylogenetic relations. In this context, nectar sugars and amino

  2. Nectar sugars and amino acids in day- and night-flowering Nicotiana species are more strongly shaped by pollinators' preferences than organic acids and inorganic ions.

    Science.gov (United States)

    Tiedge, Kira; Lohaus, Gertrud

    2017-01-01

    Floral nectar contains mainly sugars but also amino acids, organic acids, inorganic ions and secondary compounds to attract pollinators. The genus Nicotiana exhibits great diversity among species in floral morphology, flowering time, nectar compositions, and predominant pollinators. We studied nectar samples of 20 Nicotiana species, composed equally of day- and night-flowering plants and attracting different groups of pollinators (e.g. hummingbirds, moths or bats) to investigate whether sugars, amino acids, organic acids and inorganic ions are influenced by pollinator preferences. Glucose, fructose and sucrose were the only sugars found in the nectar of all examined species. Sugar concentration of the nectar of day-flowering species was 20% higher and amino acid concentration was 2-3-fold higher compared to the nectar of night-flowering species. The sucrose-to-hexose ratio was significantly higher in night-flowering species and the relative share of sucrose based on the total sugar correlated with the flower tube length in the nocturnal species. Flowers of different tobacco species contained varying volumes of nectar which led to about 150-fold higher amounts of total sugar per flower in bat- or sunbird-pollinated species than in bee-pollinated or autogamous species. This difference was even higher for total amino acids per flower (up to 1000-fold). As a consequence, some Nicotiana species invest large amounts of organic nitrogen for certain pollinators. Higher concentrations of inorganic ions, predominantly anions, were found in nectar of night-flowering species. Therefore, higher anion concentrations were also associated with pollinator types active at night. Malate, the main organic acid, was present in all nectar samples but the concentration was not correlated with pollinator type. In conclusion, statistical analyses revealed that pollinator types have a stronger effect on nectar composition than phylogenetic relations. In this context, nectar sugars and amino

  3. Raising the Sugar Content – Orchid Bees Overcome the Constraints of Suction Feeding through Manipulation of Nectar and Pollen Provisions

    Science.gov (United States)

    Pokorny, Tamara; Lunau, Klaus; Eltz, Thomas

    2014-01-01

    Unlike most other bees, the long-tongued orchid bees ingest nectar using suction feeding. Although long tongues allow exploitation of flowers with deep spurs, the energy intake rate is optimal at 10–20% lower nectar sugar concentrations compared to that of lapping bees. This constraint might be compensated by a higher digestive throughput. Additionally, orchid bees might evaporate water from regurgitated droplets of crop contents. We found male Euglossa championi (n = 10) and Euglossa dodsoni (n = 12) to regularly regurgitate droplets of crop content to the base of their proboscis, generating a fluid film between the proximal parts of the galeae, glossa and labial palps. Rhythmic movements of the proboscis may help to increase convection. There was a significant change in sugar concentration between the initially imbibed solution and the resulting crop content (Psugar concentration. Female Euglossa townsendi and Euglossa viridissima showed the same behavior. Additionally, they manipulated their nectar-enriched pollen provisions for extensive periods of time before deposition in brood cells. The deposited pollen loads (n = 14) showed a significantly higher sugar concentration than the sugar-water available to the bees (P<0.001). Thus, both male and female euglossines show behaviors that promote evaporative water loss from nectar. We suggest that the behaviors have evolved in concert with suction feeding on dilute nectar from deep floral tubes. PMID:25422945

  4. Foraging energetics of a nectar-feeding ant: metabolic expenditure as a function of food-source profitability.

    Science.gov (United States)

    Schilman, Pablo E; Roces, Flavio

    2006-10-01

    We examined the quantitative relationship between the energetic costs and benefits of nectar collection by nectar-feeding ants, Camponotus rufipes. In the laboratory, individual workers were trained to visit an artificial feeder that provided a sucrose solution of 1%, 5%, 10%, 30% or 50% at controlled flows, in a similar span range to those observed in natural nectar sources. We measured foraging times, nectar loads collected, and CO(2) production during actual feeding, as an indication of the energy expenditure for a single forager. Results show an increase in individual metabolic rates with increasing flow rate of sugar solution, but no dependence on sucrose concentration. This increase in metabolic expenditure does not depend on the crop load attained while feeding, as intuitively expected, and is therefore a result of an increased activity brought about by the food-source profitability experienced by the forager. The energy gained during collection of sugar solution is always higher than the energy spent by the ant. Even with a food source of lower quality than a natural source, the ants gain ca. tenfold of what they spend. Based on a simplified model, we calculated that foragers of C. rufipes could travel from 0.5 to 9 km with the energy gained in a single foraging trip only. These results suggest that decreasing foraging time is more important than increasing individual energetic efficiency when workers of the nectar-feeding ant C. rufipes decide to stop drinking and return to the nest with partial crop loads.

  5. High activity enables life on a high-sugar diet: blood glucose regulation in nectar-feeding bats.

    Science.gov (United States)

    Kelm, Detlev H; Simon, Ralph; Kuhlow, Doreen; Voigt, Christian C; Ristow, Michael

    2011-12-01

    High blood glucose levels caused by excessive sugar consumption are detrimental to mammalian health and life expectancy. Despite consuming vast quantities of sugar-rich floral nectar, nectar-feeding bats are long-lived, provoking the question of how they regulate blood glucose. We investigated blood glucose levels in nectar-feeding bats (Glossophaga soricina) in experiments in which we varied the amount of dietary sugar or flight time. Blood glucose levels increased with the quantity of glucose ingested and exceeded 25 mmol l(-1) blood in resting bats, which is among the highest values ever recorded in mammals fed sugar quantities similar to their natural diet. During normal feeding, blood glucose values decreased with increasing flight time, but only fell to expected values when bats spent 75 per cent of their time airborne. Either nectar-feeding bats have evolved mechanisms to avoid negative health effects of hyperglycaemia, or high activity is key to balancing blood glucose levels during foraging. We suggest that the coevolutionary specialization of bats towards a nectar diet was supported by the high activity and elevated metabolic rates of these bats. High activity may have conferred benefits to the bats in terms of behavioural interactions and foraging success, and is simultaneously likely to have increased their efficiency as plant pollinators.

  6. Simple column-switching ion chromatography method for determining eight monosaccharides and oligosaccharides in honeydew and nectar.

    Science.gov (United States)

    Ni, Chengzhu; Zhu, Binhe; Wang, Nani; Wang, Muhua; Chen, Suqing; Zhang, Jiajie; Zhu, Yan

    2016-03-01

    Honeydew is excreted by aphids as a sweet waste and nectar is floral honey. Honeydew and nectar are complicated samples which consist of various sugars and amino acids. In this work, a simple ion chromatography with column-switching method was developed for the simultaneous analysis of 8 monosaccharides and oligosaccharides in honeydew and nectar. A reversed-phase column was used as a pretreatment column to eliminate organics on-line and sugars were eluted from a collection loop to analytical column by using column-switching technique. This method showed good linearity (r⩾0.9994) and afforded low limits of detection ranging from 1.55 to 10.17μgL(-1) for all the analytes. Recoveries ranged from 95% to 105% and repeatability results were acceptable with relative standard deviation of less than 3.21% (n=6). This method was successfully applied to quantification of these sugars in honeydew and nectar. These results showed honeydew had much more oligosaccharides than nectar.

  7. Physicochemical composition, color and sensory acceptance of low-fat cupuaçu and açaí nectar: characterization and changes during storage

    Directory of Open Access Journals (Sweden)

    Eneide Taumaturgo Macambira Braga FERNANDES

    2016-01-01

    Full Text Available Abstract This study aimed to evaluate the physicochemical composition, color and sensory acceptance of low-fat açaí and cupuaçu nectar, as well as changes in these parameters during storage. Nectars were prepared with açaí pulp previously defatted by centrifugation on a pilot scale. The study consisted of two steps. In the first step, the physicochemical characteristics, instrumental color, and sensory acceptance of the nectar prepared with low-fat açaí pulp were evaluated and compared with those of nectar prepared with full-fat açaí pulp. In the second step, titratable acidity, pH, soluble solids, anthocyanin content, instrumental color, and sensory acceptance of the low-fat açaí and cupuaçu nectar were evaluated for 6 months of storage at 25°C in the absence of light. The use of low-fat açaí pulp resulted in nectars with good overall acceptance, but with lower scores for color acceptance than those of the full-fat nectar. The low-fat nectar remained stable with respect to acidity, pH, and soluble solid content during storage for up to 180 days. However, there was degradation of anthocyanins, which had a negative impact on the product color and sensory acceptance over time. Under the conditions evaluated, the estimated product shelf life is up to 120 days.

  8. Early Spring Nectar and Pollen and Insect Visitor Behavior in Two Corydalis Species (Papaveraceae

    Directory of Open Access Journals (Sweden)

    Denisow Bożena

    2014-06-01

    Full Text Available This study, conducted in 2008 and 2012 - 2013, evaluated the flowering pattern (seasonal and diurnal, the abundance of flowering, nectar, and pollen yield, and insect visitor activity for Corydalis solida (L. Clairv. and C. cava Schweig. et Koerte. The populations occur in the ground layer of a deciduous forest (Fagetalia ordo, Querco-Fagetea class in a natural gorge within the current area of the UMCS Botanical Garden in Lublin, Poland (51° 16’ N, 22° 30’ E. The phenology of Corydalis species showed distinct year-to-year plasticity (e.g., blooming period in March - April or in April - May; duration 18 - 42 days. The most intensive flower opening was noted in the early morning hours (85 - 90% of daily openings occurred between 6.00 and 10.00 h, GMT +2 h. The average sugar yield was similar at 4.6 kg/ha (C. cava and 5.2 kg/ha (C. solida, but the average pollen production differed and reached 2.1 kg/ha (C. cava and 4.1 kg/ha (C. solida. The flower-visitor interaction in Corydalis species involved both biological (early pattern of diurnal flowering, protandry, pollen presentation at the moment of anthesis and morphological (nectar hidden in deep spur features. Apis mellifera foragers predominated on both Corydalis species (mean of total visitors, 68.0% to C. solida; 62.5% to C. cava and foraged mainly for pollen (82% of foragers, while bumblebee queens (mean of total visitors, 32.0% to C. solida; 37.5% to C. cava collected mainly nectar (68.0% of foragers.

  9. The Complexity of Background Clutter Affects Nectar Bat Use of Flower Odor and Shape Cues.

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    Nathan Muchhala

    Full Text Available Given their small size and high metabolism, nectar bats need to be able to quickly locate flowers during foraging bouts. Chiropterophilous plants depend on these bats for their reproduction, thus they also benefit if their flowers can be easily located, and we would expect that floral traits such as odor and shape have evolved to maximize detection by bats. However, relatively little is known about the importance of different floral cues during foraging bouts. In the present study, we undertook a set of flight cage experiments with two species of nectar bats (Anoura caudifer and A. geoffroyi and artificial flowers to compare the importance of shape and scent cues in locating flowers. In a training phase, a bat was presented an artificial flower with a given shape and scent, whose position was constantly shifted to prevent reliance on spatial memory. In the experimental phase, two flowers were presented, one with the training-flower scent and one with the training-flower shape. For each experimental repetition, we recorded which flower was located first, and then shifted flower positions. Additionally, experiments were repeated in a simple environment, without background clutter, or a complex environment, with a background of leaves and branches. Results demonstrate that bats visit either flower indiscriminately with simple backgrounds, with no significant difference in terms of whether they visit the training-flower odor or training-flower shape first. However, in a complex background olfaction was the most important cue; scented flowers were consistently located first. This suggests that for well-exposed flowers, without obstruction from clutter, vision and/or echolocation are sufficient in locating them. In more complex backgrounds, nectar bats depend more heavily on olfaction during foraging bouts.

  10. Optimizing read-out of the NECTAr front-end electronics

    Energy Technology Data Exchange (ETDEWEB)

    Vorobiov, S., E-mail: vorobiov@lpta.in2p3.fr [LUPM, Universite Montpellier II and IN2P3/CNRS, Montpellier (France); DESY-Zeuthen, Platanenallee 6, 15738 Zeuthen (Germany); Feinstein, F. [LUPM, Universite Montpellier II and IN2P3/CNRS, Montpellier (France); Bolmont, J.; Corona, P. [LPNHE, Universite Paris VI and Universite Paris VII and IN2P3/CNRS, Paris (France); Delagnes, E. [IRFU/DSM/CEA, Saclay, Gif-sur-Yvette (France); Falvard, A. [LUPM, Universite Montpellier II and IN2P3/CNRS, Montpellier (France); Gascon, D. [ICC-UB, Universitat Barcelona, Barcelona (Spain); Glicenstein, J.-F. [IRFU/DSM/CEA, Saclay, Gif-sur-Yvette (France); Naumann, C.L.; Nayman, P. [LPNHE, Universite Paris VI and Universite Paris VII and IN2P3/CNRS, Paris (France); Ribo, M.; Sanuy, A. [ICC-UB, Universitat Barcelona, Barcelona (Spain); Tavernet, J.-P.; Toussenel, F.; Vincent, P. [LPNHE, Universite Paris VI and Universite Paris VII and IN2P3/CNRS, Paris (France)

    2012-12-11

    We describe the optimization of the read-out specifications of the NECTAr front-end electronics for the Cherenkov Telescope Array (CTA). The NECTAr project aims at building and testing a demonstrator module of a new front-end electronics design, which takes an advantage of the know-how acquired while building the cameras of the CAT, H.E.S.S.-I and H.E.S.S.-II experiments. The goal of the optimization work is to define the specifications of the digitizing electronics of a CTA camera, in particular integration time window, sampling rate, analog bandwidth using physics simulations. We employed for this work real photomultiplier pulses, sampled at 100 ps with a 600 MHz bandwidth oscilloscope. The individual pulses are drawn randomly at the times at which the photo-electrons, originating from atmospheric showers, arrive at the focal planes of imaging atmospheric Cherenkov telescopes. The timing information is extracted from the existing CTA simulations on the GRID and organized in a local database, together with all the relevant physical parameters (energy, primary particle type, zenith angle, distance from the shower axis, pixel offset from the optical axis, night-sky background level, etc.), and detector configurations (telescope types, camera/mirror configurations, etc.). While investigating the parameter space, an optimal pixel charge integration time window, which minimizes relative error in the measured charge, has been determined. This will allow to gain in sensitivity and to lower the energy threshold of CTA telescopes. We present results of our optimizations and first measurements obtained using the NECTAr demonstrator module.

  11. Weber's law, the magnitude effect and discrimination of sugar concentrations in nectar-feeding animals.

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    Vladislav Nachev

    Full Text Available Weber's law quantifies the perception of difference between stimuli. For instance, it can explain why we are less likely to detect the removal of three nuts from a bowl if the bowl is full than if it is nearly empty. This is an example of the magnitude effect - the phenomenon that the subjective perception of a linear difference between a pair of stimuli progressively diminishes when the average magnitude of the stimuli increases. Although discrimination performances of both human and animal subjects in various sensory modalities exhibit the magnitude effect, results sometimes systematically deviate from the quantitative predictions based on Weber's law. An attempt to reformulate the law to better fit data from acoustic discrimination tasks has been dubbed the "near-miss to Weber's law". Here, we tested the gustatory discrimination performance of nectar-feeding bats (Glossophaga soricina, in order to investigate whether the original version of Weber's law accurately predicts choice behavior in a two-alternative forced choice task. As expected, bats either preferred the sweeter of the two options or showed no preference. In 4 out of 6 bats the near-miss to Weber's law provided a better fit and Weber's law underestimated the magnitude effect. In order to test the generality of this observation in nectar-feeders, we reviewed previously published data on bats, hummingbirds, honeybees, and bumblebees. In all groups of animals the near-miss to Weber's law provided better fits than Weber's law. Furthermore, whereas the magnitude effect was stronger than predicted by Weber's law in vertebrates, it was weaker than predicted in insects. Thus nectar-feeding vertebrates and insects seem to differ in how their choice behavior changes as sugar concentration is increased. We discuss the ecological and evolutionary implications of the observed patterns of sugar concentration discrimination.

  12. Specialization on pollen or nectar in bumblebee foragers is not associated with ovary size, lipid reserves or sensory tuning

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    Adam R. Smith

    2016-10-01

    Full Text Available Foraging specialization allows social insects to more efficiently exploit resources in their environment. Recent research on honeybees suggests that specialization on pollen or nectar among foragers is linked to reproductive physiology and sensory tuning (the Reproductive Ground-Plan Hypothesis; RGPH. However, our understanding of the underlying physiological relationships in non-Apis bees is still limited. Here we show that the bumblebee Bombus terrestris has specialist pollen and nectar foragers, and test whether foraging specialization in B. terrestris is linked to reproductive physiology, measured as ovarian activation. We show that neither ovary size, sensory sensitivity, measured through proboscis extension response (PER, or whole-body lipid stores differed between pollen foragers, nectar foragers, or generalist foragers. Body size also did not differ between any of these three forager groups. Non-foragers had significantly larger ovaries than foragers. This suggests that potentially reproductive individuals avoid foraging.

  13. The nectary structure and nectar production in flowers of Daphne mezereum L.

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    Mirosława Chwil

    2014-04-01

    Full Text Available The genus Daphne L. comprises 100 plant species. This name is derived from the name of a nymph, one of the daughters of the rivergod Pineios, who was transformed into a laurel tree to escape the amorous Apollo. Two species, D. mezereum L. and D. cneorum L., grow in the wild in Poland. D. mezereum is more common, but it is rarely found in the whole country. D. cneorum grows in the Małopolska Upland and in the Lublin region. These taxa are fully protected in Poland. Various plant species of the genus Daphne are considered to be ornamental, medicinal, poisonous and bee plants. In the bark of D. mezereum and in leaf buds of D. odora Thunb., there is a high content of daphnin and more than 20% of coumarins. Plants of the genus Daphne are poisonous and contain harmful substances, among others a glycoside daphnin and a resinous substance mezerein. The nectaries in flowers of the family Thymelaeaceae are classified as annular or intrastaminal. The aim of this study was to analyse the location and structure of the floral nectaries as well as nectar production in flowers of D. mezereum. D. mezereum belongs to the earliest flowering (I-V melliferous plants. Densely packed flowers are borne in clusters of 2-3 in the axils of already fallen leaves. A pink corolla with fused petals has a diameter of 1-1.5 cm. Eight stamens are attached to the corolla tube. In Daphne flowers, the nectary surrounds a superior ovary borne on a gynophore. In D. merezeum, this gland forms a ring around the base of the ovary. In Daphne flowers, the stomata secrete nectar onto the nectary surface. The parenchyma cells of the nectary (longitudinal section consist of 4-7 layers. The vascular tissue supplying the nectary reaches the subnectariferous parenchyma, while the branches of phloem elements reach the base of the nectariferous parenchyma. Flowers of D. mezereum produce nectar in abundance. The colourful corolla filled with nectar attracts bees and butterflies.

  14. Time management and nectar flow: flower handling and suction feeding in long-proboscid flies (Nemestrinidae: Prosoeca)

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    Karolyi, Florian; Morawetz, Linde; Colville, Jonathan F.; Handschuh, Stephan; Metscher, Brian D.; Krenn, Harald W.

    2013-11-01

    A well-developed suction pump in the head represents an important adaptation for nectar-feeding insects, such as Hymenoptera, Lepidoptera and Diptera. This pumping organ creates a pressure gradient along the proboscis, which is responsible for nectar uptake. The extremely elongated proboscis of the genus Prosoeca (Nemestrinidae) evolved as an adaptation to feeding from long, tubular flowers. According to the functional constraint hypothesis, nectar uptake through a disproportionately elongated, straw-like proboscis increases flower handling time and consequently lowers the energy intake rate. Due to the conspicuous length variation of the proboscis of Prosoeca, individuals with longer proboscides are hypothesised to have longer handling times. To test this hypothesis, we used field video analyses of flower-visiting behaviour, detailed examinations of the suction pump morphology and correlations of proboscis length with body length and suction pump dimensions. Using a biomechanical framework described for nectar-feeding Lepidoptera in relation to proboscis length and suction pump musculature, we describe and contrast the system in long-proboscid flies. Flies with longer proboscides spent significantly more time drinking from flowers. In addition, proboscis length and body length showed a positive allometric relationship. Furthermore, adaptations of the suction pump included an allometric relationship between proboscis length and suction pump muscle volume and a combination of two pumping organs. Overall, the study gives detailed insight into the adaptations required for long-proboscid nectar feeding, and comparisons with other nectar-sucking insects allow further considerations of the evolution of the suction pump in insects with sucking mouthparts.

  15. Effects of agave nectar versus sucrose on weight gain, adiposity, blood glucose, insulin, and lipid responses in mice.

    Science.gov (United States)

    Hooshmand, Shirin; Holloway, Brittany; Nemoseck, Tricia; Cole, Sarah; Petrisko, Yumi; Hong, Mee Young; Kern, Mark

    2014-09-01

    Agave nectar is a fructose-rich liquid sweetener derived from a plant, and is often promoted as a low glycemic alternative to refined sugar. However, little scientific research has been conducted in animals or humans to determine its metabolic and/or health effects. The aim of this study was to explore the influence of agave nectar versus sucrose on weight gain, adiposity, fasting plasma blood glucose, insulin, and lipid levels. Eighteen (n=18) male ICR mice (33.8±1.6 g) were divided into two groups (n=6 for agave nectar and n=12 for sucrose) and provided free access to one of two diets of equal energy densities differing only in a portion of the carbohydrate provided. Diets contained 20% carbohydrate (by weight of total diet) from either raw agave nectar or sucrose. Epididymal fat pads were excised, and blood was collected after 34 days. Weight gain (4.3±2.2 vs. 8.4±3.4 g), fat pad weights (0.95±0.54 vs. 1.75±0.66 g), plasma glucose (77.8±12.2 vs. 111.0±27.9 mg/dL), and insulin (0.61±0.29 vs. 1.46±0.81 ng/mL) were significantly lower (P≤.05) for agave nectar-fed mice compared to sucrose-fed mice respectively. No statistically significant differences in total cholesterol or triglycerides were detected. These results suggest that in comparison to sucrose, agave nectar may have a positive influence on weight gain and glucose control. However, more research with a larger sample of animals and/or with human subjects is warranted.

  16. Amino acid and carbohydrate tradeoffs by honey bee nectar foragers and their implications for plant-pollinator interactions.

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    Hendriksma, Harmen P; Oxman, Karmi L; Shafir, Sharoni

    2014-10-01

    Honey bees are important pollinators, requiring floral pollen and nectar for nutrition. Nectar is rich in sugars, but contains additional nutrients, including amino acids (AAs). We tested the preferences of free-flying foragers between 20 AAs at 0.1% w/w in sucrose solutions in an artificial meadow. We found consistent preferences amongst AAs, with essential AAs preferred over nonessential AAs. The preference of foragers correlated negatively with AA induced deviations in pH values, as compared to the control. Next, we quantified tradeoffs between attractive and deterrent AAs at the expense of carbohydrates in nectar. Bees were attracted by phenylalanine, willing to give up 84units sucrose for 1unit AA. They were deterred by glycine, and adding 100 or more units of sucrose could resolve to offset 1unit AA. In addition, we tested physiological effects of AA nutrition on forager homing performance. In a no-choice context, caged bees showed indifference to 0.1% proline, leucine, glycine or phenylalanine in sucrose solutions. Furthermore, flight tests gave no indication that AA nutrition affected flight capacity directly. In contrast, low carbohydrate nutrition reduced the performance of bees, with important methodological implications for homing studies that evaluate the effect of substances that may affect imbibition of sugar solution. In conclusion, low AA concentrations in nectar relative to pollen suggest a limited role in bee nutrition. Most of the 20 AAs evoked a neutral to a mild deterrent response in bees, thus it seems unlikely that bees respond to AAs in nectar as a cue to assess nutritional quality. Nonetheless, free choice behavior of foraging bees is influenced, for instance by phenylalanine and glycine. Thus, AAs in nectar may affect plant-pollinator interactions and thereby exhibit a selective pressure on the flora in the honey bee habitat.

  17. Damaged-self recognition in common bean (Phaseolus vulgaris shows taxonomic specificity and triggers signalling via reactive oxygen species (ROS

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    Dalia eDuran

    2014-10-01

    Full Text Available Plants require reliable mechanisms to detect injury. Danger signals or 'damage-associated molecular patterns' (DAMPs are released from stressed host cells and allow injury detection independently of enemy-derived molecules. We studied the response of common bean (Phaseolus vulgaris to the application of leaf homogenate as a source of DAMPs and measured the production of reactive oxygen species (ROS as an early response and the secretion of extrafloral nectar (EFN as a jasmonic acid (JA–dependent late response. We observed a strong taxonomic signal in the response to different leaf homogenates. ROS formation and EFN secretion were highly correlated and responded most strongly to leaf homogenates produced using the same cultivar or closely related accessions, less to a distantly related cultivar of common bean or each of the two congeneric species, P. lunatus and P. coccineus, and not at all to homogenates prepared from species in different genera, not even when using other Fabaceae. Interestingly, leaf homogenates also reduced the infection by the bacterial pathogen, Pseudomonas syringae, when they were applied directly before challenging, although the same homogenates exhibited no direct in vitro inhibitory effect in the bacterium. We conclude that ROS signaling is associated to the induction of EFN secretion and that the specific blend of DAMPs that are released from damaged cells allows the plant to distinguish the 'damaged self' from the damaged 'non-self'. The very early responses of plants to DAMPs can trigger resistance to both, herbivores and pathogens, which should be adaptive because injury facilitates infection, independently of its causal reason.

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

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    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.

  19. Phenotypic and genotypic variability of disc flower corolla length and nectar content in sunflower

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    Joksimović Jovan

    2003-01-01

    Full Text Available The nectar content and disc flower corolla length are the two most important parameters of attractiveness to pollinators in sunflower. The phenotypic and genotypic variability of these two traits was studied in four commercially important hybrids and their parental components in a trial with three fertilizer doses over two years. The results showed that, looking at individual genotypes, the variability of disc flower corolla length was affected the most by year (85.38-97.46%. As the study years were extremely different, the phenotypic variance of the hybrids and parental components was calculated for each year separately. In such conditions, looking at all of the crossing combinations, the largest contribution to phenotypic variance of the corolla length was that of genotype: 57.27-61.11% (NS-H-45 64.51-84.84% (Velja; 96.74-97.20% (NS-H-702 and 13.92-73.17% (NS-H-111. A similar situation was observed for the phenotypic variability of nectar content, where genotype also had the largest influence, namely 39.77-48.25% in NS-H-45; 39.06-42.51% in Velja; 31.97-72.36% in NS-H-702; and 62.13-94.96% in NS-H-111.

  20. Sensory and physicochemical evaluation of acerola nectar sweetened with sucrose and different sweeteners

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    Mariana Borges de Lima Dutra

    2013-12-01

    Full Text Available This paper aims to evaluate the physicochemical characteristics, sensory acceptance, and purchase intent of acerola nectar sweetened with sucrose and other sweeteners (neotame, sucralose and stevia extracts with 40%, 60%, 80%, and 95% rebaudioside A. The analyses were carried out for pH, soluble solids, total titratable acidity, ascorbic acid, and colorimetry (L*a*b. The acceptance test was performed by 120 consumers who evaluated the appearance, aroma, flavor, texture, and overall impression of the samples using a 9-cm unstructured hedonic scale. Furthermore, the consumers were asked to rate overall purchase intent along the scale anchored with (1 "would definitely not purchase" to (5 "would definitely purchase." The results were evaluated using analysis of variance/Tukey test and the internal preference mapping technique. The acerola nectar samples did not differ significantly (p>0.05 between themselves in terms of vitamin C content and total titratable acidity. As for appearance and aroma, there was no significant difference (p>0.05 between the samples, and as for flavor and overall impression, the most accepted samples were those with sucrose and sucralose. The internal preference mapping indicated that the most accepted samples were those with sucrose, sucralose, and neotame were. The highest frequency of positive purchase intent scores was observed for sucrose and sucralose.

  1. Electrical signals during nectar sucking in the carpenter ant Camponotus mus.

    Science.gov (United States)

    Josens, Roxana; Falibene, Agustina; Gontijo, Alberto de Figueiredo

    2006-01-01

    Ants of the same size can vary their intake rate of a given sucrose solution depending on the colony's needs for carbohydrates. As this capacity has not yet been described for another insect, the question of how they can do that was the focus of our work. When viscosity and ant-morphometry remain constant, changes in intake rate can only be attributed to the sucking forces. The aim of this study was to analyze the nectar sucking activity in the ant Camponotus mus. Feeding behavior seems to be under motivational control; therefore, we developed a non-invasive experimental device. We recorded the electrical signal generated during nectar feeding by offering ants sucrose solutions of different concentrations (from 10%w/w to 70%w/w). The signal frequency was between 2 and 12 peaks/s. We could distinguish two different patterns of electrical signal during feeding depending on the solution concentration. Only the more concentrated solutions reached frequencies higher than 7 peaks/s and the signal performance was quite irregular. For the other concentrations (10%, 30% and 50%), signal frequencies were lower than 6 peaks/s and the signal pattern was sinusoidal, regular and decreased with intake in all cases. We discuss the possible implications of these two signal patterns.

  2. Nectar foraging behaviour is affected by ant body size in Camponotus mus.

    Science.gov (United States)

    Medan, Violeta; Josens, Roxana B

    2005-08-01

    The nectivorous ant Camponotus mus shows a broad size variation within the worker caste. Large ants can ingest faster and larger loads than small ones. Differences in physiological abilities in fluid ingestion due to the insect size could be related to differences in decision-making according to ant size during nectar foraging. Sucrose solutions of different levels of sugar concentration (30% or 60%w/w), viscosity (high or low) or flow rate (ad libitum or 1microl/min) were offered in combination to analyse the behavioural responses to each of these properties separately. Differences were found depending on ant body size and the property compared. A regulated flow produced smaller crop loads for medium and large ants compared to the same solution given ad libitum. All foragers remained longer times feeding at the regulated flow source but larger ants often made longer interruptions. When sugar concentration was constant but viscosity was high, only large ants increased feeding time. Constant viscosity with different sugar concentration determined longer feeding time and bigger loads for the most concentrated solution for small but not for large ants. Small ants reached similar crop loads in a variety of conditions while large ants did not. These differences could be evidence of a possible specialization for nectar foraging based on ant body size.

  3. Nectar Sources for the Honey Bee (Apis mellifera adansonii Revealed by Pollen Content

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    Olusola ADEKANMBI

    2009-11-01

    Full Text Available Nectar sources for the African honeybee Apis mellifera adansonii were investigated. The work involved analysis of three honey samples bought from open markets in Lagos, Nigeria. The pollen sediment of the honeys was acetolysed, mounted on slides and pollen types were identified and counted to determine the relative frequency of the different pollen types in the honey samples. The proportion of pollen from each of the honey samples varied from 196 in sample A, 280 in sample B to 238 in sample C. The most abundant taxa identified from the honey samples were Tridax procumbens and Elaeis guineensis belonging to the families Asteraceae and Palmae. The highest proportion of Palm pollen grain was recorded in sample B with one hundred and ten (110 pollen grains per slide. The pollen grains in the families Palmae and Asteraceae are of great importance to the bees for honey production, this can be seen in the abundance displayed in sample B and C. Other pollen taxa recovered belong to the families Mimosaceae, Euphorbiaceae, Sapotaceae and Anacardiaceae providing a clue on the ecological origin of the pollen grains in the honey sample. Pollen analysis of honey proved to be useful in deciphering nectar sources of Apis mellifera adansonii.

  4. Fluoride content of soft drinks, nectars, juices, juice drinks, concentrates, teas and infusions marketed in Portugal.

    Science.gov (United States)

    Fojo, C; Figueira, M E; Almeida, C M M

    2013-01-01

    A potentiometric method using a fluoride combination ion-selective electrode was validated and used to analyse 183 samples, including soft drinks, juices, nectars, juice drinks, concentrates, teas and infusions marketed in Portugal. The fluoride levels were higher in extract-based soft drinks, juice drinks and juice, with fluoride values of 0.86 ± 0.35, 0.40 ± 0.24 and 0.37 ± 0.11 mg l⁻¹, respectively. The lowest fluoride concentration was found in infusion samples (0.12 ± 0.01 mg l⁻¹), followed by teas and carbonated soft drinks with fluoride concentrations of 0.16 ± 0.12 and 0.18 ± 0.07 mg l⁻¹, respectively. Nectars, concentrates and juice-based drinks had similar fluoride concentrations of 0.33 ± 0.16, 0.29 ± 0.12 and 0.25 ± 0.14 mg l⁻¹, respectively. The fluoride concentrations in all these samples would only contribute intakes below the acceptable daily intake (ADI = 0.05 mg kg⁻¹ body weight day⁻¹), indicating that, individually, these beverages cannot induce fluoride toxicity in the population group of children.

  5. Ant-related oviposition is not associated to low parasitism of the myrmecophilous butterfly Allosmaitia strophius in an extrafloral nectaried shrub

    Science.gov (United States)

    Bächtold, Alexandra; Alves-Silva, Estevão; Del-Claro, Kleber

    2017-08-01

    In Lycaenidae-ant mutualisms, ovipositing females select plants based on the presence and/or species of ants in order to maximize survival rates of immatures. The ants are supposed to protect the immatures from parasitoids, but there is large variation in the protection provided. Here, we experimentally investigated whether the occurrence of the facultative myrmecophilous Allosmaitia strophius (the dominant species in our study system) was ant-related. The parasitism rates of immatures collected in the field and reared in the laboratory were also investigated. Stems of the extrafloral nectaried shrub Peixotoa tomentosa were designated as either ant-present (control) or absent (treated). The occurrence of A. strophius on ant-present stems was five times greater than on treated stems. Most eggs and larvae were associated with Camponotus blandus and Ectatomma tuberculatum, two aggressive ant species in the Brazilian savanna. Egg parasitism rate was 9%, and all the parasitized eggs were on ant-present stems. Pupal parasitism on ant-present and ant-absent stems was 25.6% and 7%, respectively. The higher parasitism rate in the presence of ants might also have been density-dependent, because caterpillars were more abundant in ant-present stems. Tropical lycaenids are frequently found in association with patrolling ants. Nevertheless, there is growing evidence that parasitism is higher in the presence of ants, owing to caterpillar's density-dependent effects in plants with ants, and/or to the weak lycaenid-ant associations. This indicates that the offspring of myrmecophilous lycaenids may not benefit, at least in terms of lower parasitism, by living with ants.

  6. Geographic variation in a facultative mutualism: consequences for local arthropod composition and diversity.

    Science.gov (United States)

    Rudgers, Jennifer A; Savage, Amy M; Rúa, Megan A

    2010-08-01

    Geographic variation in the outcome of interspecific interactions may influence not only the evolutionary trajectories of species but also the structure of local communities. We investigated this community consequence of geographic variation for a facultative mutualism between ants and wild cotton (Gossypium thurberi). Ants consume wild cotton extrafloral nectar and can protect plants from herbivores. We chose three sites that differed in interaction outcome, including a mutualism (ants provided the greatest benefits to plant fitness and responded to manipulations of extrafloral nectar), a potential commensalism (ants increased plant fitness but were unresponsive to extrafloral nectar), and a neutral interaction (ants neither affected plant fitness nor responded to extrafloral nectar). At all sites, we manipulated ants and extrafloral nectar in a factorial design and monitored the abundance, diversity, and composition of other arthropods occurring on wild cotton plants. We predicted that the effects of ants and extrafloral nectar on arthropods would be largest in the location with the mutualism and weakest where the interaction was neutral. A non-metric multidimensional scaling analysis revealed that the presence of ants altered arthropod composition, but only at the two sites in which ants increased plant fitness. At the site with the mutualism, ants also suppressed detritivore/scavenger abundance and increased aphids. The presence of extrafloral nectar increased arthropod abundance where mutual benefits were the strongest, whereas both arthropod abundance and morphospecies richness declined with extrafloral nectar availability at the site with the weakest ant-plant interaction. Some responses were geographically invariable: total arthropod richness and evenness declined by approximately 20% on plants with ants, and extrafloral nectar reduced carnivore abundance when ants were excluded from plants. These results demonstrate that a facultative ant-plant mutualism

  7. Asymmetrical disassortative pollination in a distylous primrose: the complementary roles of bumblebee nectar robbers and syrphid flies.

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    Zhu, Xing-Fu; Jiang, Xian-Feng; Li, Li; Zhang, Zhi-Qiang; Li, Qing-Jun

    2015-01-12

    Heterostyly is a floral polymorphism characterized by reciprocal herkogamy maintained through high levels of mating between morphs, serviced by appropriate pollinators. We studied how differential efficiency and abundance of distinct pollinators affect plant female reproduction in self- and intra-morph incompatible distylous Primula secundiflora. Bumblebees and syrphid flies were found to be the most abundant floral visitors. Bumblebees frequently exhibited nectar-robbing behavior. Because the robbing holes were always situated between the high- and low-level organs on both morphs, nectar-robbing bumblebees only pollinated S-styled flowers. L-styled flowers set four times as many seeds as did S-styled flowers after being visited by pollen-collecting syrphid flies. The natural female fecundity and the magnitude of pollen limitation varied between the morphs within populations because of the mosaic distribution of nectar-robbing bumblebees and syrphid flies. L-styled flowers and S-styled flowers set the same number of seeds after supplemental hand pollination, indicating equivalent female reproductive potential. We suggest that bumblebee nectar robbers and syrphid flies play an important role in sustaining the floral dimorphism of heterostyly in P. secundiflora because of their complementary roles in the pollination system.

  8. Nectar-providing plants enhance the energetic state of herbivores as well as their parasitoids under field conditions

    NARCIS (Netherlands)

    Winkler, K.; Wackers, F.; Pinto, D.M.

    2009-01-01

    1. The use of flowering vegetation has been widely advocated as a strategy for providing parasitoids and predators with nectar and pollen. However, their herbivorous hosts and prey may exploit floral food sources as well. 2. Previous laboratory studies have shown that not all flower species are equa

  9. Unique proline-benzoquinone pigment from the colored nectar of "bird's Coca cola tree" functions in bird attractions.

    Science.gov (United States)

    Luo, Shi-Hong; Liu, Yan; Hua, Juan; Niu, Xue-Mei; Jing, Shu-Xi; Zhao, Xu; Schneider, Bernd; Gershenzon, Jonathan; Li, Sheng-Hong

    2012-08-17

    The major pigment responsible for the dark brown nectar of the "bird's Coca cola tree", Leucosceptrum canum (Labiatae), was isolated and identified as a unique symmetric proline-quinone conjugate, 2,5-di-(N-(-)-prolyl)-para-benzoquinone (DPBQ). Behavioral experiments with both isolated and synthetic authentic samples indicated that DPBQ functions mainly as a color attractant to bird pollinators.

  10. Comparative pollination biology of Venezuelan columnar cacti and the role of nectar-feeding bats in their sexual reproduction.

    Science.gov (United States)

    Nassar, J; Ramirez, N; Linares, O

    1997-07-01

    The floral biology, reproductive system, and visitation behavior of pollinators of four species of columnar cacti, Stenocereus griseus, Pilosocereus moritzianus, Subpilocereus repandus, and Subpilocereus horrispinus, were studied in two arid zones in the north of Venezuela. Our results support the hypothesis that Venezuelan species of columnar cacti have evolved toward specialization on bat pollination. Additional information on the floral biology of a fifth species, Pilosocereus lanuginosus, was also included. All species showed the typical traits that characterize the pollination syndrome of chiropterophily. All species but Pilosocereus moritzianus were obligate outcrossers. Nectar and pollen were restricted to nocturnal floral visitors. Two species of nectar-feeding bats, Leptonycteris curasoae Miller and Glossophaga longirostris Miller, were responsible for practically all the fruit set in these cacti. Frequency of bat visitation per flower per night was highly variable within and between species of cactus, with average frequencies varying between 27 and 78 visits/flower/night. In general terms, the pattern of floral visitation through the night was significantly correlated with the pattern of nectar production and nectar sugar concentration for all species of cactus. Under natural pollination, fruit:flower ratios varied from 0.46 in Subpilocereus repandus to 0.76 in Stenocereus griseus. The efficiency of bat pollination in terms of seed:ovule ratio was high in all species, varying between 0.70 and 0.94.

  11. The effects of plant density and nectar reward on bee visitation to the endangered orchid Spiranthes romanzoffiana

    Science.gov (United States)

    Duffy, Karl J.; Stout, Jane C.

    2008-09-01

    Density can affect attraction of pollinators, with rare plants receiving fewer pollinating visits compared with more common co-flowering species. However, if a locally rare species is very attractive in terms of the rewards it offers pollinators, it may be preferentially visited. Spiranthes romanzoffiana is a nectar rewarding, geographically rare, endangered orchid species which forms small populations in Ireland, co-flowering with more common, florally rewarding species. We examined visitation rates to S. romanzoffiana and two nectar rewarding co-flowering species ( Mentha aquatica and Prunella vulgaris) in the west of Ireland. These three plant species were visited by three bee species ( Bombus pascuorum, B. hortorum and Apis mellifera). B. pascuorum was the most common visitor, while A. mellifera was least common. Our results suggest that individual S. romanzoffiana inflorescences compete intraspecifically for visitation from pollinators at high densities. The relationship between visitation to S. romanzoffiana and total floral density appeared to be positive, suggesting interspecific facilitation of pollinator visitation at high densities. Nectar standing crop varied through the season, among species and between open and bagged flowers. Nectar standing crop was not correlated with visitation in S. romanzoffiana. Despite relatively high visitation, S. romanzoffiana produced no mature fruit during this flowering season. The lack of fruit maturation in this species may be a major factor causing its rarity in Europe.

  12. Presence of yeasts in floral nectar is consistent with the hypothesis of microbial-mediated signaling in plant-pollinator interactions.

    Science.gov (United States)

    Pozo, María I; de Vega, Clara; Canto, Azucena; Herrera, Carlos M

    2009-11-01

    Olfactory floral signals are significant factors in plant-pollinator mutualisms. Recently, unusual fermentation odors have been described in the nectar and flowers of some species. Since yeasts are common inhabitants of many angiosperms nectars, this raises the possibility that nectar yeasts may act as causal agents of fermentation odors in flowers and, therefore, as possible intermediate agents in plant signaling to pollinators. A recent field study has reported that nectar yeasts were quite frequent in floral nectar across three different regions in Europe and America, where they reached high densities (up to 10(5) cells/mm(3)). Yeast incidence in floral nectar differed widely across plant host species in all sampling sites. A detailed study currently in progress on one of the species surveyed in that study (Helleborus foetidus, Ranunculaceae) has detected that, in addition to interespecific differences in yeast incidence, there is also a strong component of variance in yeast abundance that takes place at the subindividual level (among flowers of the same plant, among nectaries of the same flower). If yeast metabolism is eventually proved to contribute significantly to floral scent, then multilevel patchiness in the distribution of nectar yeasts (among species, among individuals within species, and among flowers and nectaries of the same individual) might contribute to concomitant multilevel variation in plant signaling and, eventually, also in pollination success, pollen flow and plant fitness.

  13. 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.

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

    Directory of Open Access Journals (Sweden)

    Caitlin J Oliver

    Full Text Available 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.

  15. Preferential nectar robbing of flowers with long corollas: experimental studies of two hummingbird species visiting three plant species.

    Science.gov (United States)

    Lara, Carlos; Ornelas, Juan

    2001-07-01

    Long flower tubes have been traditionally viewed as the result of coevolution between plants and specialized, legitimate, long billed-pollinators. However, nectar robbers may have played a role in selection acting on corolla length. This study evaluated whether hummingbirds are more likely to rob flowers with longer corollas from which they cannot efficiently extract nectar with legitimate visits. We compared two hummingbird species with similar bill lengths (Lampornis amethystinus and Colibri thalassinus) visiting floral arrays of artificial flowers with exaggerated corolla lengths, and also evaluated how the birds extract nectar rewards from medium to long corollas of three hummingbird-pollinated plants (Salvia mexicana, S. iodantha and Ipomoea hederifolia). The consequences of foraging for plant fitness were evaluated in terms of seed production per flower. Variation in seed production after legitimate visits of hummingbird-pollinated plants was mostly explained by differences in pollinator effectiveness. Seed production did not increase with the number of legitimate visits to a flower, except in I. hederifolia. We found that birds were more likely to rob both artificial and natural flowers with long corolla tubes. Nectar robbing was not observed on short-corolla flowers of Salvia spp., but robbing negatively affected seed production of long-tubed flowers of I. hederifolia. Significant differences between hummingbird species in the use of this behavior were observed, but males and females behaved alike. We suggest that short-billed hummingbirds with enlarged bill serrations (the edge of both tomia finely toothed) may have an advantage in illegitimately feeding at long-corolla flowers. This raises the possibility of counter-selection on increasing corolla length by nectar robbers.

  16. Competitive impacts of an invasive nectar thief on plant-pollinator mutualisms

    Science.gov (United States)

    Hanna, Cause; Foote, David; Kremen, Claire

    2014-01-01

    Plant–pollinator mutualisms are disrupted by a variety of competitive interactions between introduced and native floral visitors. The invasive western yellowjacket wasp, Vespula pensylvanica, is an aggressive nectar thief of the dominant endemic Hawaiian tree species, Metrosideros polymorpha. We conducted a large-scale, multiyear manipulative experiment to investigate the impacts of V. pensylvanica on the structure and behavior of the M. polymorpha pollinator community, including competitive mechanisms related to resource availability. Our results demonstrate that V. pensylvanica, through both superior exploitative and interference competition, influences resource partitioning and displaces native and nonnative M. polymorpha pollinators. Furthermore, the restructuring of the pollinator community due to V. pensylvanica competition and predation results in a significant decrease in the overall pollinator effectiveness and fruit set of M. polymorpha. This research highlights both the competitive mechanisms and contrasting effects of social insect invaders on plant–pollinator mutualisms and the role of competition in pollinator community structure.

  17. Macroecologia das interações entre plantas e aves nectarívoras

    OpenAIRE

    Zanata,Thais Bastos

    2014-01-01

    Resumo: As principais famílias de aves nectarívoras são Trochilidae (beija-flores, nas Américas), Nectariniidae (sunbirds, na África e Ásia) e Meliphagidae (honeyeaters, na Oceania). Comparações entre essas famílias e as plantas que visitam apontam uma maior especialização nas comunidades da família Trochilidae, seguida por Nectariniidae e Meliphagidae. O objetivo do primeiro capítulo é descrever estas comunidades de aves e plantas em relação ao número de famílias, gêneros e espécies, assim c...

  18. Determination of changes induced by gamma radiation in nectar of kiwi fruit (Actinidia deliciosa)

    Energy Technology Data Exchange (ETDEWEB)

    Harder, M.N.C.; De Toledo, T.C.F.; Ferreira, A.C.P. [Centro de Energia Nuclear na Agricultura (CENA/USP), Laboratorio de Irradiacao de Alimentos e Radioentomologia, Av. Centenario, 303, Piracicaba CEP 13400-970 Sao Paulo (Brazil); Arthur, V. [Centro de Energia Nuclear na Agricultura (CENA/USP), Laboratorio de Irradiacao de Alimentos e Radioentomologia, Av. Centenario, 303, Piracicaba CEP 13400-970 Sao Paulo (Brazil)], E-mail: arthur@cena.usp.br

    2009-07-15

    The kiwi (Actinidia deliciosa; Actinidaceae) is an exotic fruit to Brazil, introduced from southeastern China. The kiwi fruit presents a high nutritional value, rich mainly in vitamin C and fibers, calcium, iron and phosphorus, which give it an excellent nutritional value. Its quality attributes and flavor has lead to acceptance in consuming markets, mainly among children. The objective of this work was to formulate a non-alcoholic sweetened drink based on kiwi fruits, to submit the drink to gamma radiation using increasing doses: 0 (control), 0.5, 1.0 and 2.0 kGy, and to evaluate changes in physical and chemical quality attributes. We found that no significant difference was observed between treatments relative to the control. So we could conclude that for the doses tested significant alterations in the physiochemical characteristics of the kiwi nectar were introduced.

  19. Determination of changes induced by gamma radiation in nectar of kiwi fruit ( Actinidia deliciosa)

    Science.gov (United States)

    Harder, M. N. C.; De Toledo, T. C. F.; Ferreira, A. C. P.; Arthur, V.

    2009-07-01

    The kiwi ( Actinidia deliciosa; Actinidaceae) is an exotic fruit to Brazil, introduced from southeastern China. The kiwi fruit presents a high nutritional value, rich mainly in vitamin C and fibers, calcium, iron and phosphorus, which give it an excellent nutritional value. Its quality attributes and flavor has lead to acceptance in consuming markets, mainly among children. The objective of this work was to formulate a non-alcoholic sweetened drink based on kiwi fruits, to submit the drink to gamma radiation using increasing doses: 0 (control), 0.5, 1.0 and 2.0 kGy, and to evaluate changes in physical and chemical quality attributes. We found that no significant difference was observed between treatments relative to the control. So we could conclude that for the doses tested significant alterations in the physiochemical characteristics of the kiwi nectar were introduced.

  20. Foraging reactivation in the honeybee Apis mellifera L.: factors affecting the return to known nectar sources

    Science.gov (United States)

    Gil, Mariana; Farina, Walter Marcelo

    2002-05-01

    This paper addresses, what determines that experienced forager honeybees return to places where they have previously exploited nectar. Although there was already some evidence that dance and trophallaxis can cause bees to return to feed, the fraction of unemployed foragers that follow dance or receive food from employed foragers before revisiting the feeder was unknown. We found that 27% of the experienced foragers had no contact with the returning foragers inside the hive. The most common interactions were dance following (64%) and trophallaxis (21%). The great variability found in the amount of interactions suggests that individual bees require different stimulation before changing to the foraging mode. This broad disparity negatively correlated with the number of days after marking at the feeder, a variable that is closely related to the foraging experience, suggesting that a temporal variable might affect the decision-making in reactivated foragers.

  1. Wendlandia tinctoria (Roxb. DC. (Rubiaceae, a key nectar source for butterflies during the summer season in the southern Eastern Ghats, Andhra Pradesh, India

    Directory of Open Access Journals (Sweden)

    A.J.S. Raju

    2011-03-01

    Full Text Available Wendlandia tinctoria is a semi-evergreen tree species. It shows massive flowering for about a month during March-April. The floral characteristics such as the white colour of the flower, lack of odour, short-tubed corolla with deep seated nectar having 15-18% sugar concentration are well tailored for visitation by butterflies. The nectar is hexose-rich and contains the essential amino acids such as arginine and histidine and the non-essential amino acids such as alanine, aspartic acid, cysteine, glysine, hydroxyproline, tyrosine, glutamic acid and serine. The inflorescences with clusters of flowers provide an excellent platform for foraging by butterflies. The flowers are long-lived and attractive to butterflies. A variety of butterflies visit the flowers for nectar and in doing so, they pollinate them. Nymphalids are very diverse and utilize the flowers until exhausted. The flowers being small in size with a small amount of nectar compel the butterflies to do a more laborious search for nectar from a greater number of flowers. But, the clustered state of the flowers is energetically profitable for butterflies to reduce search time and also flight time to collect a good amount of nectar; such a probing behaviour is advantageous for the plant to achieve self- and cross-pollination. Therefore, the study shows that the association between W. tinctoria and butterflies is mutual and such an association is referred to as psychophilous. This plant serves as a key nectar source for butterflies at the study site where floral nectar sources are scarce during the summer season.

  2. Floral Phenology, Nectar Secretion Dynamics, and Honey Production Potential, of Two Lavender Species (Lavandula Dentata, and L. Pubescens in Southwestern Saudi Arabia

    Directory of Open Access Journals (Sweden)

    Nuru Adgaba

    2015-12-01

    Full Text Available The aim of the current study was to determine the floral phenology, nectar secretion dynamics, and honey production potentials of two naturally growing lavender species (L. dentata and L. pubescens, in southwestern Saudi Arabia. In both species, flowering is continuous. This means that, when open flowers on a spike are shaded, new flowers emerge. Such a flowering pattern might be advantageous to the plant to minimise competition for pollinators and promote efficient resource allocation. The flowering periods of the two species overlap. Both species secreted increasing amounts of nectar from early morning to late afternoon. The mean maximum volumes of accumulated nectar from bagged flowers occurred at 15:00 for L. pubescens (0.50 ± 0.24 μL/flower and at 18:00 for L. dentata (0.68 ± 0.19 μL/flower. The volume of the nectar that became available between two successive measurements (three-h intervals varied from 0.04 μL/flower to 0.28 μL/flower for L. pubescens and from 0.04 μL/flower to 0.35 μL/ flower for L. dentata, This variation reflects the differences in the dynamics of nectar secretion by these species, and indicates the size of the nectar that may be available for flower visitors at given time intervals. The distribution of nectar secretions appears to be an adaptation of the species to reward pollinators for longer duration. Based on the mean amount of nectar sugar secreted by the plants, the honey production potentials of the species are estimated to be 4973.34 mg and 3463.41 mg honey/plant for L. dentata and L. pubescens, respectively.

  3. Beyond the pollination syndrome: nectar ecology and the role of diurnal and nocturnal pollinators in the reproductive success of Inga sessilis (Fabaceae).

    Science.gov (United States)

    Amorim, F W; Galetto, L; Sazima, M

    2013-03-01

    Inga species present brush-type flower morphology allowing them to be visited by distinct groups of pollinators. Nectar features in relation to the main pollinators have seldom been studied in this genus. To test the hypothesis of floral adaptation to both diurnal and nocturnal pollinators, we studied the pollination ecology of Inga sessilis, with emphasis on the nectar secretion patterns, effects of sequential removals on nectar production, sugar composition and the role of diurnal and nocturnal pollinators in its reproductive success. Inga sessilis is self-incompatible and pollinated by hummingbirds, hawkmoths and bats. Fruit set under natural conditions is very low despite the fact that most stigmas receive polyads with sufficient pollen to fertilise all ovules in a flower. Nectar secretion starts in the bud stage and flowers continually secreting nectar for a period of 8 h. Flowers actively reabsorbed the nectar a few hours before senescence. Sugar production increased after nectar removal, especially when flowers were drained during the night. Nectar sugar composition changed over flower life span, from sucrose-dominant (just after flower opening, when hummingbirds were the main visitors) to hexose-rich (throughout the night, when bats and hawkmoths were the main visitors). Diurnal pollinators contributed less than nocturnal ones to fruit production, but the former were more constant and reliable visitors through time. Our results indicate I. sessilis has floral adaptations, beyond the morphology, that encompass both diurnal and nocturnal pollinator requirements, suggesting a complementary and mixed pollination system. © 2012 German Botanical Society and The Royal Botanical Society of the Netherlands.

  4. A comparison of antioxidative capacities of fruit juices, drinks and nectars, as determined by EPR and UV-vis spectroscopies.

    Science.gov (United States)

    Bartoszek, Mariola; Polak, Justyna

    2016-01-15

    The differences in the Trolox Equivalent Antioxidant Capacity (TEAC) values at the same incubation time obtained by two different techniques: electron paramagnetic resonance (EPR) spectroscopy and ultraviolet visible (UV-vis) spectroscopy, which use the same antioxidant-free radical reaction mechanism, were determined for fruit juices, nectars and drinks. For this study, the stable free radical 1,1-Diphenyl-2-picryl-hydrazyl (DPPH(•)) was used. The antioxidant capacity was presented in Trolox Equivalents, e.g., μM trolox per 100 ml of sample. All of the studied fruit juices, drinks and nectars showed antioxidative properties. Dependencies between TEAC values and the percent fruit content and sample color were observed for the studied beverages. It was found that EPR spectroscopy is the more adequate method for determining TEAC values for these kinds of samples.

  5. Chromolaena odorata (L.) King & H.E. Robins (Asteraceae), an important nectar source for adult butterflies

    OpenAIRE

    P.V. Lakshmi; A.J.S. Raju

    2011-01-01

    Chromolaena odorata is a seasonal weed and grows like a cultivated crop. It flowers during October-December. The floral characteristics such as white to purple colour of florets, short-tubed narrow corolla with deep seated nectar, the morning anthesis and the flat-topped head inflorescence providing a standing platform are important attractants for visitation by butterflies. The florets attract butterflies of five families and sphingid hawk moths. Among the butterflies, nymphalids are diverse...

  6. Development of pitanga nectar with different sweeteners by sensory analysis: ideal pulp dilution, ideal sweetness, and sweetness equivalence

    Directory of Open Access Journals (Sweden)

    Mírian Luisa Faria Freitas

    2014-03-01

    Full Text Available The objective of this study was to develop pitanga nectar formulations in which sucrose was replaced with different sweeteners. Consumer tests were conducted with 50 fruit juice consumers, and a just-about-right scale was used to determine the ideal pulp dilution and ideal sweetness with sucrose. Furthermore, the adequate concentrations of six sweeteners were determined to obtain the equivalent sweetness of sucrose using relative to these concentrations the magnitude estimation model with 19 selected assessors. The ideal dilution test resulted in 25% pulp, and the ideal sweetness test, 10% sucrose. Sweetener concentrations to replace sucrose were 0.0160%, 0.0541%, 0.1000%, 0.0999%, 0.0017%, and 0.0360%, respectively, for sucralose, aspartame, stevia 40% rebaudioside A, stevia 95% rebaudioside A, neotame, and a 2:1 cyclamate/saccharin blend. These results can be used to prepare pitanga nectar with different sweeteners and obtain the same sweetness intensity in less caloric products than that of nectar prepared with sucrose.

  7. Changes in guava (Psidium guajava L. var. Paluma nectar volatile compounds concentration due to thermal processing and storage

    Directory of Open Access Journals (Sweden)

    Maria Ivaneide Coutinho Correa

    2010-12-01

    Full Text Available Guava nectars were formulated for approximately 10, 12, or 14 ºBrix, with 40% guava pulp. Sodium benzoate, 500 mg.kg-1 was used as preservative. The Brix value was adjusted with saturated sucrose syrup. The guava nectar was pasteurized (85 ºC/42 seconds in tubular heat exchanger and then hot filled in 500 mL white glass bottles. The products were stored either at room temperature (25 ± 5 ºC or refrigerated (5 ± 2 ºC under fluorescent light exposure and analyzed on the day after processing (time zero and also 40, 80, and 120 days of storage. Eight compounds were identified and quantified by Gas Chromatography (GC -Mass Spectrometry (MS: hexanal, (E-hex-2-enal, 1-hexenol, (Z-hex-3-enol, (Z-hex-3-enyl acetate, phenyl-3-propyl acetate, cinnamyl acetate, and acetic acid. There was no significant effect of thermal treatment on the volatile compound concentrations, except for a significant decrease (p = 0.0001 in hexanal and (Z-hex-3-enyl acetate (p = 0.0029. As for the storage time, there was a much greater decrease in the esters contents, such as (Z-hex-3-enyl and phenyl-3-propyl acetates. Cinnamyl acetate had the greatest decrease over storage time. Refrigeration was better than room temperature for guava nectar volatile compounds stability over storage time, mainly for esters compounds, which are important for the product aroma and flavor

  8. Nectar and Pollen Sources for Honeybee (Apis cerana cerana Fabr.) in Qinglan Mangrove Area, Hainan Island, China

    Institute of Scientific and Technical Information of China (English)

    Yi-Feng Yao; Subir Bera; Yu-Fei Wang; Cheng-Sen Li

    2006-01-01

    In the present study, nectar and pollen sources for honeybee (Apis cerana cerana Fabr.) were studied in Qinglan mangrove area, Hainan Island, China, based on microscopic analysis of honey and pollen load (corbicular and gut contents) from honeybees collected in October and November 2004. Qualitative and quantitative melittopalynological analysis of the natural honey sample showed that the honey is of unifloral type with Mimosa pudica L. (Mimosaceae) as the predominant (89.14%) source of nectar and pollen for A.cerana cerana in October. Members of Araceae are an important minor (3%-15%) pollen type, whereas those of Arecaceae are a minor (<3%) pollen type. Pollen grains of Nypa fruticans Wurmb., Rhizophora spp.,Excoecaria agallocha L., Lumnitzera spp., Bruguiera spp., Kandelia candel Druce, and Ceriops tagal (Perr.)C. B. Rob. are among the notable mangrove taxa growing in Qinglan mangrove area recorded as minor taxa in the honey, The absolute pollen count (i.e. the number of pollen grains/10 g honey sample) suggests that the honey belongs to Group Ⅴ (>1 000 000). Pollen analysis from the corbicular and gut contents of A. cerana cerana revealed the highest representation (95.60%) of members of Sonneratia spp. (Sonneratiaceae),followed by Bruguiera spp. (Rhizophoraceae), Euphorbiaceae, Poaceae, Fabaceae, Arecaceae, Araceae,Anacardiaceae, and Rubiaceae. Of these plants, those belonging to Sonneratia plants are the most important nectar and pollen sources for A. cerana cerana and are frequently foraged and pollinated by these bees in November.

  9. Survey about Nectar Plant Resources in Maolan Nature Reserve%茂兰自然保护区野生蜜源植物资源调查

    Institute of Scientific and Technical Information of China (English)

    覃龙江; 冉景丞; 姚正明; 刘绍飞; 莫家伟; 唐安学; 蒙会理

    2012-01-01

    After four years of research on wild nectar plants in Maolan Nature Reserve, the distribution, habitats and biological traits of those nectar plants were introduced in details, and some suggestions were given on their utilization status and development prospect. The results showed that there are up to 148 kinds of wild nectar plant resources, including 46 kinds of main wild nectar plants, belonging to 19 families 34 genera;90 kinds of auxiliary nectar plants, belonging to 33 families, 64 genera; 12 kinds of toxic nectar plants, attached to the 9 families, 10 genera.This study is to describe in details the flowering and habitat of wild nectar plants,and put forward some suggestions on its development, utilization and prospects.%通过对茂兰自然保护区野生蜜源植物资源进行了4年的调查研究,对野生蜜源植物的分布情况、生境特点和生物学性状做详细介绍,并对其开发利用现状及前景分析提出建议.结果表明,茂兰自然保护区内有野生蜜源植物资源多达148种,其中主要野生蜜源植物46种,隶属19科、34属;辅助蜜源植物90种,隶属33科、64属;有毒蜜源植物12种,隶属9科、10属.从种类构成上看,该区野生蜜源植物的优势科为豆科和蔷薇科,其次是山茶科、唇形科、菊科.

  10. Patterns of pollen and nectar foraging specialization by bumblebees over multiple timescales using RFID

    Science.gov (United States)

    Russell, Avery L.; Morrison, Sarah J.; Moschonas, Eleni H.; Papaj, Daniel R.

    2017-01-01

    The ecological success of social insects is frequently ascribed to improvements in task performance due to division of labour amongst workers. While much research has focused on improvements associated with lifetime task specialization, members of colonies can specialize on a given task over shorter time periods. Eusocial bees in particular must collect pollen and nectar rewards to survive, but most workers appear to mix collection of both rewards over their lifetimes. We asked whether bumblebees specialize over timescales shorter than their lifetime. We also explored factors that govern such patterns, and asked whether reward specialists made more foraging bouts than generalists. In particular, we described antennal morphology and size of all foragers in a single colony and related these factors to each forager’s complete foraging history, obtained using radio frequency identification (RFID). Only a small proportion of foragers were lifetime specialists; nevertheless, >50% of foragers specialized daily on a given reward. Contrary to expectations, daily and lifetime reward specialists were not better foragers (being neither larger nor making more bouts); larger bees with more antennal olfactory sensilla made more bouts, but were not more specialized. We discuss causes and functions of short and long-term patterns of specialization for bumblebee colonies. PMID:28181584

  11. Evaluation of nectar of kiwi (Actinidia deliciosa) submitted to gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Harder, Marcia N C.; Toledo, Tais C.F. de; Ferreira, Andrea C.P.; Arthur, Valter [Centro de Energia Nuclear na Agricultura (CENA), Piracicaba, SP (Brazil). Lab. de Irradiacao de Alimentos e Radioentomologia]. E-mails: mnharder@cena.usp.br; tcftoled@cena.usp.br; andrea@dtr.com.br; arthur@cena.usp.br; Spoto, Marta H.F. [Escola Superior de Agricultura Luiz de Queiroz(ESALQ/USP), Piracicaba, SP (Brazil)]. E-mail: mhfspoto@esalq.usp.br

    2007-07-01

    The kiwi is an exotic fruit, it is pertaining the Actinidaceae family, possesses high nutritional value, being rich mainly in vitamin C and fibers, calcium, iron and phosphorus, what turns it a good nutritious option, presenting an important associated attribute the quality of the fruits and the flavor, what be comes it a fruit with great acceptance in the consuming markets, mainly children. The irradiation is an excellent method of conservation, as well as an accomplice to reinforce the action of other applied processes with the same purpose. The objective of this work was to formulate a sweetened drink, no alcoholic, starting from the kiwi (Actinidia deliciosa), to submit its at the gamma radiation for source of Co{sup 60} with doses of: 0 (control); 0.5; 1.0 and 2.0 kGy in a tax of dose of 0.712 kGy/hour, and subsequent physiochemical and sensorial analyses for detection of possible alterations provoked by the radiation. It is possible to conclude that the radiation in the doses used did not promote significant alterations in the physiochemical and sensorial characteristics of the kiwi nectar. (author)

  12. Evaluation of antioxidant and mutagenic activities of honey-sweetened cashew apple nectar.

    Science.gov (United States)

    da Silva, Robson Alves; Dihl, Rafael Rodrigues; Nascimento e Santos, Débora; de Abreu, Bianca Regina Ribas; de Lima, Alessandro; de Andrade, Heloisa Helena Rodrigues; Lehmann, Mauricio

    2013-12-01

    In vitro chemical properties and antioxidant potential and in vivo mutagenic activity of honey-sweetened cashew apple nectar (HSCAN), a beverage produced from the cashew pseudo-fruit (Anacardium occidentale L.) and of its constituents were assessed. Analytical procedures were carried out to investigate the honey used in the HSCAN preparation, and the results observed are in accordance with Brazilian legal regulations, except for diastase number. HSCAN and pulp were investigated for ascorbic acid, carotenoid, anthocyanin and total phenolic contents, and both showed high acid ascorbic concentrations. Antioxidant capacity using 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) and/or β-carotene/linoleic acid systems were applied and demonstrated a weak antioxidant capacity of honey and HSCAN, but cashew apple pulp demonstrated high antioxidant capacity. A weakly positive mutagenic effect of cashew pulp 20% was observed using the somatic mutation and recombination test (SMART) in Drosophila melanogaster only in the high-bioactivation (HB) cross. On the contrary, HSCAN was not mutagenic in both standard and high bioactivation crosses. HSCAN exhibited slight antioxidant activity, which could be associated with the high amount of ascorbic acid found in the samples evaluated. The beverage prepared did not induce DNA damage in somatic cells of D. melanogaster, which means that it is neither mutagenic nor recombinagenic in this test system.

  13. Metabolomic Profiling of the Nectars of Aquilegia pubescens and A. Canadensis.

    Directory of Open Access Journals (Sweden)

    Christos Noutsos

    Full Text Available To date, variation in nectar chemistry of flowering plants has not been studied in detail. Such variation exerts considerable influence on pollinator-plant interactions, as well as on flower traits that play important roles in the selection of a plant for visitation by specific pollinators. Over the past 60 years the Aquilegia genus has been used as a key model for speciation studies. In this study, we defined the metabolomic profiles of flower samples of two Aquilegia species, A. Canadensis and A. pubescens. We identified a total of 75 metabolites that were classified into six main categories: organic acids, fatty acids, amino acids, esters, sugars, and unknowns. The mean abundances of 25 of these metabolites were significantly different between the two species, providing insights into interspecies variation in floral chemistry. Using the PlantSEED biochemistry database, we found that the majority of these metabolites are involved in biosynthetic pathways. Finally, we explored the annotated genome of A. coerulea, using the PlantSEED pipeline and reconstructed the metabolic network of Aquilegia. This network, which contains the metabolic pathways involved in generating the observed chemical variation, is now publicly available from the DOE Systems Biology Knowledge Base (KBase; http://kbase.us.

  14. Defining the suitability for nectar production, bee bread and honeydew in managed forests (Trentino, Italy

    Directory of Open Access Journals (Sweden)

    Miori M

    2007-01-01

    Full Text Available The project’s aim was to locate the wooden areas suitable for beekeeping activities. This has been possible thanks to the use of a multi-parametric model. This permits to define, for each of 85 forestal types of Trentino, the suitability for the production of nectar, bee bread and honeydew. According to the results, forestal types have been divided into 4 productivity classes. Datas have been reprocessed with GIS methodology so that high and medium productivity areas have been mapped. Following, new parameters have been introduced (distance from roads, slope, exposure in order to highlight in the map the economically most important areas for beekeeping activities. In the next stage the apiaries’ position in the examined areas have been registered with the GPS. These registrations have been used in order to compare the theoretical results with the actual beekeeping activities’ distribution. The experimental stage showed that this methodology represents an useful tool to support beekeeping and, more in general, forest planning.

  15. Aumento da Sobrevivência de Aedes (Stegomyia aegypti (Linnaeus, em Condições de Laboratório, pela Ingestão de Néctar Extrafloral de Euphorbia milii Des Moul. (Euphorbiaceae

    Directory of Open Access Journals (Sweden)

    Nathalia Oliveira

    2014-04-01

    Abstract. The objective this study was to determine if in laboratory, Aedes (Stegomyia aegypti (L., an important vector of dengue and yellow fever, feeds on the nectar of Euphorbia milii Des Moul (Euphorbiaceae , plant commonly used in homes as a hedge, and evaluate the effect of feeding on survival. The lifetime of both sexes was checked daily and a test for fructose was used for verification of sugar intake by mosquitoes. The daily access to the nectar gave a significant increase in the lifetime of males and females (12.8 and 18.4 days, respectively in relation to mosquitoes maintained only with water (6.4 and 7.4 days, respectively. Plants in domestic environments, producing nectar and suitable for feeding by mosquitoes of the same, as well as E. milii, have the potential to play a significant role in the energy budget of mosquitoes. An increase in the survival of females can mean an increased likelihood of infection and disease transmission in males and an increased likelihood of insemination of females. Although often overlooked in research and control tactics, the propensity of the mosquito Ae. aegypti ingesting sugars can be a variable that confers advantages to this vector.

  16. Evolutionary change from induced to constitutive expression of an indirect plant resistance.

    Science.gov (United States)

    Heil, Martin; Greiner, Sabine; Meimberg, Harald; Krüger, Ralf; Noyer, Jean-Louis; Heubl, Günther; Linsenmair, K Eduard; Boland, Wilhelm

    2004-07-08

    Induced plant resistance traits are expressed in response to attack and occur throughout the plant kingdom. Despite their general occurrence, the evolution of such resistances has rarely been investigated. Here we report that extrafloral nectar, a usually inducible trait, is constitutively secreted by Central American Acacia species that are obligately inhabited by ants. Extrafloral nectar is secreted as an indirect resistance, attracting ants that defend plants against herbivores. Leaf damage induces extrafloral nectar secretion in several plant species; among these are various Acacia species and other Fabaceae investigated here. In contrast, Acacia species obligately inhabited by symbiotic ants nourish these ants by secreting extrafloral nectar constitutively at high rates that are not affected by leaf damage. The phylogeny of the genus Acacia and closely related genera indicate that the inducibility of extrafloral nectar is the plesiomorphic or 'original' state, whereas the constitutive extrafloral nectar flow is derived within Acacia. A constitutive resistance trait has evolved from an inducible one, obviously in response to particular functional demands.

  17. Selection and breeding of honey bees for higher or lower collection of avocado nectar.

    Science.gov (United States)

    Afik, Ohad; Dag, Arnon; Yeselson, Yelena; Schaffer, Arthur; Shafir, Sharoni

    2010-04-01

    Intensive activity of honey bees, Apis mellifera L., is essential for high fruit set in avocado, Persea americana Mill., orchards, but even when hives are located inside the orchard, many bees still search for alternative blooms. We tested for a possible genetic component for a preference of avocado bloom relative to competing bloom. The honey from each hive was extracted at the end of the avocado bloom and the concentration of perseitol, a carbohydrate that is unique to avocado, was analyzed as a measure for avocado foraging. During the first year, five bee strains were compared in three different sites in Israel. Significant differences were found between strains in honey perseitol concentrations, suggesting differences in their efficiency as avocado pollinators, although these differences were site dependent. At two sites, colonies with the highest and lowest perseitol concentrations were selected as parental "high" and "low" lines. Queens were raised from the selected colonies and were instrumentally inseminated by drones from other colonies of this line. During the second and third years, colonies with inseminated queens were introduced to the avocado orchards, together with the selected colonies still surviving from the previous year. Colonies of the high line had greater perseitol concentrations than those of the low line. Selected colonies that survived from the previous year performed consistently vis-à-vis perseitol concentration, in the second year of testing. Heritability value of 0.22 was estimated based on regression of offspring on midparent. The results reveal a heritable component for willingness of honey bees to collect avocado nectar.

  18. The thermal niche of Neotropical nectar-feeding bats: Its evolution and application to predict responses to global warming.

    Science.gov (United States)

    Ortega-García, Stephanie; Guevara, Lázaro; Arroyo-Cabrales, Joaquín; Lindig-Cisneros, Roberto; Martínez-Meyer, Enrique; Vega, Ernesto; Schondube, Jorge E

    2017-09-01

    The thermal niche of a species is one of the main determinants of its ecology and biogeography. In this study, we determined the thermal niche of 23 species of Neotropical nectar-feeding bats of the subfamily Glossophaginae (Chiroptera, Phyllostomidae). We calculated their thermal niches using temperature data obtained from collection records, by generating a distribution curve of the maximum and minimum temperatures per locality, and using the inflection points of the temperature distributions to estimate the species optimal (STZ) and suboptimal (SRZ) zones of the thermal niche. Additionally, by mapping the values of the STZ and SRZ on a phylogeny of the group, we generated a hypothesis of the evolution of the thermal niches of this clade of nectar-feeding bats. Finally, we used the characteristics of their thermal niches to predict the responses of these organisms to climate change. We found a large variation in the width and limits of the thermal niches of nectar-feeding bats. Additionally, while the upper limits of the thermal niches varied little among species, their lower limits differ wildly. The ancestral reconstruction of the thermal niche indicated that this group of Neotropical bats evolved under cooler temperatures. The two clades inside the Glossophaginae differ in the evolution of their thermal niches, with most members of the clade Choeronycterines evolving "colder" thermal niches, while the majority of the species in the clade Glossophagines evolving "warmer" thermal niches. By comparing thermal niches with climate change models, we found that all species could be affected by an increase of 1°C in temperature at the end of this century. This suggests that even nocturnal species could suffer important physiological costs from global warming. Our study highlights the value of scientific collections to obtain ecologically significant physiological data for a large number of species.

  19. Does exogenous carbon extend the realized niche of canopy lichens? Evidence from sub-boreal forests in British Columbia.

    Science.gov (United States)

    Campbell, Jocelyn; Bengtson, Per; Fredeen, Arthur L; Coxson, Darwyn S; Prescott, Cindy E

    2013-05-01

    Foliose lichens with cyanobacterial bionts (bipartite and tripartite) form a distinct assemblage of epiphytes strongly associated with humid microclimatic conditions in inland British Columbia. Previous research showed that these cyano- and cephalolichen communities are disproportionately abundant and species-rich on conifer saplings beneath Populus compared to beneath other tree species. More revealing, lichens with cyanobacterial bionts were observed beneath Populus even in stands that did not otherwise support them. We experimentally test the hypothesis that this association is due to the interception of glucose-rich nectar that is exuded from Populus extra-floral nectaries (EFN). Using CO2 flux measurements and phospholipid fatty acid (PLFA) analysis with experimental applications of 13C6-labeled glucose, we demonstrate that cyano- and cephalolichens have a strong respiratory response to glucose. Lichens treated with glucose had lower net photosynthesis and higher establishment rates than control thalli. Furthermore, lichens with cyanobacterial bionts rapidly incorporate exogenous 13C into lichen fatty acid tissues. A large proportion of the 13C taken up by the lichens was incorporated into fungal biomarkers, suggesting that the mycobiont absorbed and assimilated the majority of applied 13C6 glucose. Our observations suggest that both cyanolichens and cephalolichens may utilize an exogenous source of glucose, made available by poplar EFNs. The exogenous C may enable these lichens to become established by providing a source of C for fungal respiration despite drought-induced inactivity of the cyanobacterial partner. As such, the mycobiont may adopt an alternative nutritional strategy, using available exogenous carbon to extend its realized niche.

  20. From foraging to operant conditioning: a new computer-controlled Skinner box to study free-flying nectar gathering behavior in bees.

    Science.gov (United States)

    Sokolowski, Michel B C; Abramson, Charles I

    2010-05-15

    The experimental study of nectar foraging behavior in free-flying bees requires the use of automated devices to control solution delivery and measure dependent variables associated with nectar gathering. We describe a new computer-controlled artificial flower and provide calibration data to measure the precision of the apparatus. Our device is similar to a "Skinner box" and we present data of an experiment where various amounts of a 50% sugar solution are presented randomly to individual bees. These data show large individual variations among subjects across several dependent variables. Finally, we discuss possible applications of our device to problems in behavioral sciences.

  1. Arboreal ants use the "Velcro(R principle" to capture very large prey.

    Directory of Open Access Journals (Sweden)

    Alain Dejean

    Full Text Available Plant-ants live in a mutualistic association with host plants known as "myrmecophytes" that provide them with a nesting place and sometimes with extra-floral nectar (EFN and/or food bodies (FBs; the ants can also attend sap-sucking Hemiptera for their honeydew. In return, plant-ants, like most other arboreal ants, protect their host plants from defoliators. To satisfy their nitrogen requirements, however, some have optimized their ability to capture prey in the restricted environment represented by the crowns of trees by using elaborate hunting techniques. In this study, we investigated the predatory behavior of the ant Azteca andreae which is associated with the myrmecophyte Cecropia obtusa. We noted that up to 8350 ant workers per tree hide side-by-side beneath the leaf margins of their host plant with their mandibles open, waiting for insects to alight. The latter are immediately seized by their extremities, and then spread-eagled; nestmates are recruited to help stretch, carve up and transport prey. This group ambush hunting technique is particularly effective when the underside of the leaves is downy, as is the case for C. obtusa. In this case, the hook-shaped claws of the A. andreae workers and the velvet-like structure of the underside of the leaves combine to act like natural Velcro that is reinforced by the group ambush strategy of the workers, allowing them to capture prey of up to 13,350 times the mean weight of a single worker.

  2. Arboreal ants use the "Velcro(R) principle" to capture very large prey.

    Science.gov (United States)

    Dejean, Alain; Leroy, Céline; Corbara, Bruno; Roux, Olivier; Céréghino, Régis; Orivel, Jérôme; Boulay, Raphaël

    2010-06-25

    Plant-ants live in a mutualistic association with host plants known as "myrmecophytes" that provide them with a nesting place and sometimes with extra-floral nectar (EFN) and/or food bodies (FBs); the ants can also attend sap-sucking Hemiptera for their honeydew. In return, plant-ants, like most other arboreal ants, protect their host plants from defoliators. To satisfy their nitrogen requirements, however, some have optimized their ability to capture prey in the restricted environment represented by the crowns of trees by using elaborate hunting techniques. In this study, we investigated the predatory behavior of the ant Azteca andreae which is associated with the myrmecophyte Cecropia obtusa. We noted that up to 8350 ant workers per tree hide side-by-side beneath the leaf margins of their host plant with their mandibles open, waiting for insects to alight. The latter are immediately seized by their extremities, and then spread-eagled; nestmates are recruited to help stretch, carve up and transport prey. This group ambush hunting technique is particularly effective when the underside of the leaves is downy, as is the case for C. obtusa. In this case, the hook-shaped claws of the A. andreae workers and the velvet-like structure of the underside of the leaves combine to act like natural Velcro that is reinforced by the group ambush strategy of the workers, allowing them to capture prey of up to 13,350 times the mean weight of a single worker.

  3. Cyanogenesis of Wild Lima Bean (Phaseolus lunatus L.) Is an Efficient Direct Defence in Nature

    Science.gov (United States)

    Ballhorn, Daniel J.; Kautz, Stefanie; Heil, Martin; Hegeman, Adrian D.

    2009-01-01

    In natural systems plants face a plethora of antagonists and thus have evolved multiple defence strategies. Lima bean (Phaseolus lunatus L.) is a model plant for studies of inducible indirect anti-herbivore defences including the production of volatile organic compounds (VOCs) and extrafloral nectar (EFN). In contrast, studies on direct chemical defence mechanisms as crucial components of lima beans' defence syndrome under natural conditions are nonexistent. In this study, we focus on the cyanogenic potential (HCNp; concentration of cyanogenic glycosides) as a crucial parameter determining lima beans' cyanogenesis, i.e. the release of toxic hydrogen cyanide from preformed precursors. Quantitative variability of cyanogenesis in a natural population of wild lima bean in Mexico was significantly correlated with missing leaf area. Since existing correlations do not by necessity mean causal associations, the function of cyanogenesis as efficient plant defence was subsequently analysed in feeding trials. We used natural chrysomelid herbivores and clonal lima beans with known cyanogenic features produced from field-grown mother plants. We show that in addition to extensively investigated indirect defences, cyanogenesis has to be considered as an important direct defensive trait affecting lima beans' overall defence in nature. Our results indicate the general importance of analysing ‘multiple defence syndromes’ rather than single defence mechanisms in future functional analyses of plant defences. PMID:19424497

  4. 常春油麻藤有气味花蜜及其生态功能%Scented nectar of Mucuna sempervirens and its ecological function

    Institute of Scientific and Technical Information of China (English)

    陈高; 张蕊蕊; 董坤; 公维昌; 马永鹏

    2012-01-01

    Scented nectar secreted by flowers is an interesting natural phenomenon in angiosperms that is often overlooked by most researchers. Scented nectar is an evolutionary feature coupling the behavior between flower-visitors and their rewards. The effect of scented nectar on pollinator or nectar-thief is a scientific problem which deserves further exploration. We evaluated Mucuna sempervirens flowering dynamics, floral nectar volatiles, behaviors of Dremomys pernyi and Callosciurus erythraeus to inflorescence opening, nectar's attraction effect to Apis cerana cerana, and the toxic effect of M sempervirens nectar to Tapinoma sp. Aliphatic compounds (87.2%) were the main volatiles in nectar of M. sempervirens, whereas ketones accounted for 56.1% of the total volatiles. Lastly, volatile components with sulfur elements were absent from nectar samples. Previous studies of bat pollinated plant species have found that plants in the genus Mucuna always release sulfur compounds. Additionally, we found that the nectar of M. sempervirens was poisonous to Tapinoma sp. ant species, whereas it attracted A. cerana cerana using the Y olfactory bioassay. Squirrel species (D. pernyi and C. erythraeus) were effective pollinators of M sempervirens, so we suspected that M. sempervirens might not be pollinated by bats only. This study provides data of pollination mechanisms in Mucuna and provides a new perspective of composition and function study of nectar in other plant groups in future.%一些被子植物能够分泌有气味的花蜜,但这一自然现象很少被关注.作为嗅觉信号线索,有气味的花蜜可能是将访花者和气味信号结合在一起的特征,它与传粉者及盗蜜者的关系值得探索.本研究以常春油麻藤(Mucuna sempervirens)为对象,研究了其开花动态及泊氏长吻松鼠(Dremomys pernyi)和赤腹松鼠(Callosciurus erythraeus)的访花行为,采用顶空固相微萃取和气相色谱-质谱法收集并分析了花蜜的挥发物成

  5. EFNS guideline on the treatment of tension-type headache - report of an EFNS task force

    DEFF Research Database (Denmark)

    Bendtsen, L; Kalsmose-Hjelmborg, Simon Evers; Linde, M.

    2010-01-01

    and relaxation training most likely are effective. Physical therapy and acupuncture may be valuable options for patients with frequent TTH, but there is no robust scientific evidence for efficacy. Simple analgesics and non-steroidal anti-inflammatory drugs are recommended for the treatment of episodic TTH...... points. Recommendations: Non-drug management should always be considered although the scientific basis is limited. Information, reassurance and identification of trigger factors may be rewarding. Electromyography (EMG) biofeedback has a documented effect in TTH, whilst cognitive-behavioural therapy...... of first choice for the prophylactic treatment of chronic TTH. Mirtazapine and venlafaxine are drugs of second choice. The efficacy of the prophylactic drugs is often limited, and treatment may be hampered by side effects...

  6. EFNS guideline on the treatment of tension-type headache - report of an EFNS task force

    DEFF Research Database (Denmark)

    Bendtsen, L; Evers, S; Linde, Marianne

    2010-01-01

    and relaxation training most likely are effective. Physical therapy and acupuncture may be valuable options for patients with frequent TTH, but there is no robust scientific evidence for efficacy. Simple analgesics and non-steroidal anti-inflammatory drugs are recommended for the treatment of episodic TTH...

  7. EFNS guidelines on cognitive rehabilitation: report of an EFNS task force.

    Science.gov (United States)

    Cappa, S F; Benke, T; Clarke, S; Rossi, B; Stemmer, B; van Heugten, C M

    2005-09-01

    Disorders of language, spatial perception, attention, memory, calculation and praxis are a frequent consequence of acquired brain damage [in particular, stroke and traumatic brain injury (TBI)] and a major determinant of disability. The rehabilitation of aphasia and, more recently, of other cognitive disorders is an important area of neurological rehabilitation. We report here a review of the available evidence about effectiveness of cognitive rehabilitation. Given the limited number and generally low quality of randomized clinical trials (RCTs) in this area of therapeutic intervention, the Task Force considered, besides the available Cochrane reviews, evidence of lower classes which was critically analysed until a consensus was reached. In particular, we considered evidence from small group or single cases studies including an appropriate statistical evaluation of effect sizes. The general conclusion is that there is evidence to award a grade A, B or C recommendation to some forms of cognitive rehabilitation in patients with neuropsychological deficits in the post-acute stage after a focal brain lesion (stroke, TBI). These include aphasia therapy, rehabilitation of unilateral spatial neglect (ULN), attentional training in the post-acute stage after TBI, the use of electronic memory aids in memory disorders, and the treatment of apraxia with compensatory strategies. There is clearly a need for adequately designed studies in this area, which should take into account specific problems such as patient heterogeneity and treatment standardization.

  8. EFNS guidelines on cognitive rehabilitation: report of an EFNS task force.

    NARCIS (Netherlands)

    Cappa, S.F.; Benke, T.; Clarke, S.; Rossi, B.; Stemmer, B.; Heugten, C.M. van

    2005-01-01

    Disorders of language, spatial perception, attention, memory, calculation and praxis are a frequent consequence of acquired brain damage [in particular, stroke and traumatic brain injury (TBI)] and a major determinant of disability. The rehabilitation of aphasia and, more recently, of other cognitiv

  9. Reproductive biology and nectar production of the Mexican endemic Psittacanthus auriculatus (Loranthaceae), a hummingbird-pollinated mistletoe.

    Science.gov (United States)

    Pérez-Crespo, M J; Ornelas, J F; Martén-Rodríguez, S; González-Rodríguez, A; Lara, C

    2016-01-01

    Many mistletoe species produce 'bird'-pollinated flowers; however, the reproductive biology of the majority of these species has not been studied. Psittacanthus auriculatus is a Mexican endemic mistletoe, most common in open, dry mesquite grassland. Knowledge of the reproductive biology of P. auriculatus is essential for understanding species formation and diversification of Psittacanthus mistletoes, but it is currently poorly understood. Thus, we studied floral biology and phenology, nectar production and breeding system and pollination of this species. The hermaphroditic red-pink flowers open from the middle to the tip and petals are curly, but remain partially fused forming a floral tube of ca. 20-mm long. Flowers are partially protandrous, produce large amounts of nectar, last 2 days, and stigma receptivity is highest during the second day. We recorded hummingbirds (Cynanthus latirostris, Hylocharis leucotis, Amazilia beryllina, A. violiceps, Calothorax lucifer, Archilochus colubris) and less commonly butterflies (Agraulis vanillae, Anteos clorinde, Papilio multicaudatus, Phocides urania, Phoebis sennae) as floral visitors. P. auriculatus flowers are self-compatible. However, this mistletoe is an obligate animal-pollinated species, as the sensitive stigma avoids self-pollination. Under natural conditions, reproductive success was higher than in manually selfed or cross-pollinated flowers, likely due to the traplining foraging behaviour of hummingbirds. We suggest that the apparent efficient foraging behaviour of hummingbirds maintains gene flow among P. auriculatus, promoting outcrossing.

  10. Amyloplast to chromoplast conversion in developing ornamental tobacco floral nectaries provides sugar for nectar and antioxidants for protection.

    Science.gov (United States)

    Horner, H T; Healy, R A; Ren, G; Fritz, D; Klyne, A; Seames, C; Thornburg, R W

    2007-01-01

    Tobacco floral nectaries undergo changes in form and function. As nectaries change from green to orange, a new pigment is expressed. Analysis demonstrated that it is β-carotene. Plastids undergo dramatic changes. Early in nectary development, they divide and by stage 9 (S9) they are engorged with starch. About S9, nectaries shift from quiescent anabolism to active catabolism resulting in starch breakdown and production of nectar sugars. Starch is replaced by osmiophilic bodies, which contain needle-like carotenoid crystals. Between S9 and S12, amyloplasts are converted to chromoplasts. Changes in carotenoids and ascorbate were assayed and are expressed at low levels early in development; however, following S9 metabolic shift, syntheses of β-carotene and ascorbate greatly increase in advance of expression of nectar redox cycle. Transcript analysis for carotenoid and ascorbate biosynthetic pathways showed that these genes are significantly expressed at S6, prior to the S9 metabolic shift. Thus, formation of antioxidants β-carotene and ascorbate after the metabolic shift is independent of transcriptional regulation. We propose that biosynthesis of these antioxidants is governed by availability of substrate molecules that arise from starch breakdown. These processes and events may be amenable to molecular manipulation to provide a better system for insect attraction, cross pollination, and hybridization.

  11. Dieta de murciélagos nectarívoros del Parque Nacional Cerros de Amotape, Tumbes

    Directory of Open Access Journals (Sweden)

    Edith Arias

    2011-07-01

    Full Text Available En el Perú se reporta la presencia de 18 especies de murciélagos nectarívoros, sin embargo se cuenta con poca información sobre la dieta de estas especies. En este estudio se reporta por primera vez la dieta de los nectarívoros Glossophaga soricina, Lonchophylla hesperia y Anoura geoffroyi en el bosque seco ecuatorial y del bosque tropical del Pacífico del Parque Nacional Cerros de Amotape, Tumbes. Analizamos 21 contenidos gastrointestinales e identificamos ocho morfotipos de polen pertenecientes a las familias Bombacaceae, Cactaceae, Fabaceae, Solanaceae, Rubiaceae, Myrtaceae, Malvaceae y Rosaceae. Encontramos evidencia del síndrome de quiropterofilia en Bombacaceae, Cactaceae, Fabaceae, Solanaceae y Rubiaceae. Observamos que A. geoffroyi consume polen de Ceiba trichistandra, Solanaceae y Rubiacea; G. soricina consume de Abutilon reflexum, Armathocereus cartwrightianus, C. trichistandra y Rubiaceae; y L. hesperia de A. cartwrightianus, Eriobotrya japonica, Fabaceae y Psidium sp.; sugiriendo una dieta generalista en estas especies. Los murciélagos G. soricina y A. geoffroyi comparten el consumo del ceibo C. trichistandra y de la Rubiaceae, mientras que G. soricina comparte con L. hesperia el consumo del cactus A. cartwrightianus. Los otros morfotipos de polen no fueron compartidos entre murciélagos. Se encuentra además que el ceibo C. trichistandra fue la especie más consumida, especialmente por G. soricina.

  12. Production Optimization of Low-Calorie Orange Nectar Using Stevioside Sweetener and Evaluation of Its Physicochemical Properties during Storage

    Directory of Open Access Journals (Sweden)

    S. Hosseini

    2015-09-01

    Full Text Available Nowadays low-calorie products are increasingly becoming popular. One of the methods to produce low-calorie food is replacement of sugar (sucrose with low-calorie sweeteners such as stevioside. This compound is isolated from the leaves of the Paraguayan plant, Stevia rebaudiana Bertoni. Since orange juice is a popular beverage with an important role in human nutrition, production of low-calorie orange nectar (containing 60% natural juice and optimization of formulation parameters using response surface methodology (RSM was the purpose of this study. Three levels of independent variables, sugar, stevioside and pectin were used to optimize formulation and two responses of brix and viscosity were evaluated. After the determination of the best formula, they were produced and stored at refrigerator (4°C and ambient (25°C temperatures for 60 days and their physicochemical properties were measured in 20 days intervals. The results showed that after 60 days of storage, stevioside content was reduced (5%. Sucrose, turbidity and viscosity were reduced during storage but brix did not indicate a notable change over the course of the study. These changes were greater at the higher storage temperature (except brix. At the end of the storage, optimal treatment had higher turbidity and total phenolic contents than the blank sample. Results showed that it is possible to produce orange nectar with 70% decrease in its sugar content by using 0.06% of stevioside and 0.03% of pectin, without any significant effects on physicochemical and sensory properties.

  13. Stabilization of a functional refreshment from mango nectar and yacon (Smallanthus sonchifolius through spray drying encapsulation

    Directory of Open Access Journals (Sweden)

    Torres-Valenzuela Laura Sofía

    2014-02-01

    Full Text Available Background: Yacon syrup (YS may be implemented as a functional sweetener because of its concentration of fructooligosaccharides (FOS, which are sugars that are resistant to enzymatic hydrolysis in the human digestive tract. Additionally, health benefits related to the consumption of FOS have been reported, such as preventing constipation and reducing blood sugar and lipid levels in diabetic patients. Yacon is a tuber from the South American Andes region, and its nutraceutical effects have been researched. Objective: The effect of YS as sweetener in a Mango Nectar (MN stabilized through SD (which is? and encapsulated with maltodextrin and Arabic gum (AG was evaluated as a natural and alternative beverage for diabetic patients. Methods: A sequential experimental design was used. First, mangoes were characterized into three ripening stages, evaluating pH, TSS, WC, WA, and TTA of each stage. Then, four formulations of MN with YS with concentrations of 33.3, 66.6, and 99.9% yacon-to-juice ratio were evaluated according to the quantity of TSS, which were analyzed over the acceptance of untrained judges. Later on, the formulation with the best acceptance was chosen and evaluated based on the performance of the encapsulation of components through SD using maltodextrin and AG with a 30% concentration and tricalcium phosphate (TP with a 0.15% concentration. Lastly, the encapsulation process with maltodextrin with a 30% concentration was analyzed at temperatures of 100, 105, 110, and 130°C over the rehydration, evaluating WA, TSS, and Vitamin C. Results: The mango with 12°Brix was selected for the formulation. The YS addition to MN generated significant differences (p<0.001 in the flavor because of the concentration with the addition of a 33.3% enhancing the flavor. As a result, the 33.3% concentration was selected for further testing. The final stage showed significant differences in the performance of the processFunctional Foods in Health and Disease

  14. Flower morphology, nectar features, and hummingbird visitation to Palicourea crocea (Rubiaceae in the Upper Paraná River floodplain, Brazil

    Directory of Open Access Journals (Sweden)

    Luciana B. Mendonça

    2006-03-01

    Full Text Available We investigated flower morphology, nectar features, and hummingbird visitation to Palicourea crocea (Rubiaceae, a common ornithophilous shrub found in the riparian forest understory in the Upper Paraná River floodplain, Brazil. Flowers are distylous and the style-stamen dimorphism is accompanied by other intermorph dimorphisms in corolla length, anther length, and stigma lobe length and form. We did not observe strict reciprocity in the positioning of stigma and anthers between floral morphs. Flowering occurred during the rainy season, October to December. Nectar standing crop per flowerwas relatively constant throughout the day, which apparently resulted in hummingbirds visiting the plant throughout the day. Energetic content of the nectar in each flower (66.5J and that required daily by hummingbird visitors (up to 30kJ would oblige visits to hundreds of flowers each day, and thus movements between plants that should result in pollen flow. Three hummingbird species visited the flowers: the Gilded Sapphire (Hylocharis chrysura, the Black-throated Mango (Anthracothorax nigricollis, and the Glittering-bellied Emerald (Chlorostilbon aureoventris. The frequency of hummingbird visitation, nectar features, and the scarcity of other hummingbird-visited flowers in the study area, indicate that P. crocea is an important nectar resource for short-billed hummingbirds in the study site.Investigamos a morfologia floral, as características do néctar e a visita de beija-flores a Palicourea crocea (Rubiaceae, uma espécie ornitófila arbustiva comumente encontrada no sub-bosque da vegetação ripária na planície de inundação do Alto Rio Paraná, Brasil. As flores são distílicas, sendo o dimorfismo estilete-estames acompanhado por outras variações morfológicas no comprimento da corola, altura das anteras, comprimento das anteras e comprimento e forma das papilas estigmáticas. Não foi observada reciprocidade estrita na posição dos estigmas e

  15. 黏虫蜜源植物花蜜比较特征时空稳定性的初步研究%Preliminary Study on Stability of Time and Space of Comparative Characteristics of Nectar from Oriental Armyworm Moth Nectar Plants

    Institute of Scientific and Technical Information of China (English)

    余洋; 范新涛; 王高平

    2013-01-01

    紫云英和油菜是黏虫春季迁飞路径上的常见蜜源植物,已发现河南省罗山县中午和下午紫云英花蜜糖含量和单花泌蜜量均低于油菜,确定2种蜜源植物花蜜这些比较特征的稳定性是揭示紫云英更适合黏虫的基础.为此,采集并测定了江西婺源紫云英和油菜花蜜糖含量、单花泌蜜量.结果表明:在江西婺源,盛花期油菜中午及下午的花蜜糖含量(分别为53.77%、40.93%)显著高于同时间的紫云英(分别为35.17%、31.50%)(P<0.05),而在早上两者的花蜜糖含量相近;盛花期油菜单花泌蜜量在早上、中午及下午均为同时间紫云英单花泌蜜量的10倍以上.这些结果与河南省罗山县的花蜜特征具有部分相似性,即盛花期紫云英中午及下午的花蜜糖含量、单花泌蜜量均显著低于同时间油菜的花蜜糖含量、单花泌蜜量(P<0.05),初步说明紫云英和油菜花蜜单花泌蜜量和糖含量的比较特征具有一定的时空稳定性.%Milk vetch(Astragalus sinicus) and rape (Brassica napus) are common nectar plants for oriental armyworm moth (Mythmina separata) migration in the spring.It is reported that the nectar sugar content and single flower nectar volume of rape are higher than those of milk vetch at moon and afternoon in Luoshan county,Henan.Determination of comparative characteristics of the two kinds of nectar is the basic work to reveal the fit mechanism of milk vetch for armyworm moth.The two kinds of nectar were collected in Wuyuan county,Jiangxi,and the sugar content and single flower nectar volume of the two nectar plants were determined.The results showed that the nectar sugar content of rape and milk vetch in the full-bloom stage was not significantly different in the morning,but the rape's nectar sugar content at noon and afternoon (53.77%,40.93%) was significantly higher than that of milk vetch (35.17%,31.50%)(P<0.05).At the same time,the rape's single flower

  16. Accumulation of human EGF in nectar of transformed plants of Nicotiana langsdorffii x N. sanderae and transfer to honey by bees.

    Science.gov (United States)

    Helsper, J P F G; Ruyter-Spira, C P; Kwakman, P H S; Bleeker, W K; Keizer, L C P; Bade, J B; Te Velde, A A; Zaat, S A J; Verbeek, M; Creemers-Molenaar, J

    2011-09-01

    Honey has been used successfully in wound healing for thousands of years. The peptide hormone human epidermal growth factor (hEGF) is also known to have a beneficial effect in various wound healing processes via mechanisms that differ from those for honey. In this study, we show that hEGF can be incorporated into honey via nectar. Plants of Nicotiana langsdorffii x N. sanderae were transformed with the gene for hEGF, equipped with a nectary-targeted promoter and a signal sequence for secretion to nectar. These plants accumulated hEGF in the nectar. The maximum hEGF concentration recorded with ELISA in these plants is 2.5 ng·ml⁻¹. There is a significant linear relationship (Pplants did not allow production of honey from their nectar, we used feeding solutions, spiked with synthetic hEGF, to study transfer of this peptide into honey through bee activity. Transfer of hEGF from a feeding solution to honey by bees occurred with retention of the hEGF concentration and the capacity to induce hEGF-receptor phosphorylation. These observations indicate that plants can function as a production platform for honey containing biologically active peptides, which may enhance wound healing and other biological processes.

  17. Synergistic potential of papaya and strawberry nectar blends focused on specific nutrients and antioxidants using alternative thermal and non-thermal processing techniques.

    Science.gov (United States)

    Swada, Jeffrey G; Keeley, Christopher J; Ghane, Mohammad A; Engeseth, Nicki J

    2016-05-15

    Traditional processing has detrimental effects on nutrient value of fruit nectars; however, combining fruit nectars prior to processing can result in synergistic outcomes, e.g., a combination of nutrients providing a greater effect than they would individually, thus offsetting these losses. To examine this food synergism, papaya and strawberry nectars and their respective blends (25P:75S, 50P:50S, 75P:25S) were processed using ultra high temperature (UHT) and irradiation and examined for ascorbic acid concentration, carotenoid concentration, and antioxidant capacity. Ascorbic acid concentration was best retained after UHT processing, with synergistic relationships in all blends. Synergistic relationships were observed for β-cryptoxanthin concentration after irradiation. β-Carotene experienced both antagonistic and additive relationships whereas lycopene concentration encountered synergistic relationships in the 25P:75S blend for both techniques. All blends exhibited synergistic relationships for antioxidant capacity after UHT processing. These findings demonstrate the benefits of blending fruit nectars; producing a superior product than either fruit processed individually.

  18. The occurrence and evolution of nectar extraction apparatus among Hymenoptera ‘Symphyta'. Jervis, M. & Vilhelmsen, L

    DEFF Research Database (Denmark)

    Vilhelmsen, Lars

    2000-01-01

    , plant (angiosperm) sap, the juice of ripe fruit, the spermatial fluid of rust fungi, sternorrhynchan bug honeydew, and insect tissues. Adults show feeding-related mouthpart specialization either for consuming pollen (the Xyelidae only) or for consuming ‘concealed' floral nectar (several families). Seven...

  19. Thermal Processing Alters the Chemical Quality and Sensory Characteristics of Sweetsop (Annona squamosa L.) and Soursop (Annona muricata L.) Pulp and Nectar.

    Science.gov (United States)

    Baskaran, Revathy; Ravi, Ramasamy; Rajarathnam, Somasundaram

    2016-01-01

    The objective of this study was to investigate the effect of thermal processing on the chemical quality and sensory characteristics of Annona squamosa L. and Annona muricata L. fruit pulps and nectar. The fruit pulps were pasteurized at 85 °C for 20 min and nectar prepared as per Food Safety and Standards Authority of India (FSSAI) specifications. The chemical composition of fresh and heated pulps of A. squamosa and A. muricata showed that compared to fresh, the chemical profile and sensory profile changed in heated samples and nectar. The free and bound phenolics of A. squamosa increased in heated pulp (127.61 to 217.22 mg/100 g and 150.34 to 239.74 mg/100 g, respectively), while in A. muricata, free phenolics increased very marginally from 31.73 to 33.74 mg/100 g and bound phenolics decreased from 111.11 to 86.91 mg/100 g. This increase in phenolic content may be attributed to the perception of bitterness and astringency in A. squamosa pulp on heating. In electronic tongue studies, principal component analysis (PCA) confirmed that the fresh and heated pulps had different scores, as indicated by sensory analysis using qualitative descriptive analysis (QDA). E-tongue analysis of samples discriminated the volatile compounds released from the heated A. squamosa and A. muricata fruit pulps and nectar in their respective PCA plots by forming different clusters.

  20. Long-term temporal variation in the organization of an ant–plant network

    Science.gov (United States)

    Díaz-Castelazo, Cecilia; Sánchez-Galván, Ingrid R.; Guimarães, Paulo R.; Raimundo, Rafael L. Galdini; Rico-Gray, Víctor

    2013-01-01

    Background and Aims Functional groups of species interact and coevolve in space and time, forming complex networks of interacting species. A long-term study of temporal variation of an ant–plant network is presented with the aims of: (1) depicting its structural changes over a 20-year period; (2) detailing temporal variation in network topology, as revealed by nestedness and modularity analysis and other parameters (i.e. connectance, niche overlap); and (3) identifying long-term turnover in taxonomic structure (i.e. switches in ant resource use or plant visitor assemblages according to taxa). Methods Fieldwork was carried out at La Mancha, Mexico, and ant–plant interactions were observed between 1989 and 1991, between 1998 and 2000, and between May 2010 and 2011. Occurrences of ants on extrafloral nectaries (EFNs) were recorded. The resulting ant–plant networks were constructed from qualitative presence–absence data determined by a species–species matrix defined by the frequency of occurrence of each pairwise ant–plant interaction. Key Results Network variation across time was stable and a persistent nested structure may have contributed to the maintenance of resilient and species-rich communities. Modularity was lower than expected, especially in the most recent networks, indicating that the community exhibited high overlap among interacting species (e.g. few species were hubs in the more recent network, being partly responsible for the nested pattern). Structurally, the connections created among modules by super-generalists gave cohesion to subsets of species that otherwise would remain unconnected. This may have allowed an increasing cascade-effect of evolutionary events among modules. Mutualistic ant–plant interactions were structured 20 years ago mainly by the subdominant nectarivorous ant species Camponotus planatus and Crematogaster brevispinosa, which monopolized the best extrafloral nectar resources and out-competed other species with broader

  1. Long-term temporal variation in the organization of an ant-plant network.

    Science.gov (United States)

    Díaz-Castelazo, Cecilia; Sánchez-Galván, Ingrid R; Guimarães, Paulo R; Raimundo, Rafael L Galdini; Rico-Gray, Víctor

    2013-06-01

    Functional groups of species interact and coevolve in space and time, forming complex networks of interacting species. A long-term study of temporal variation of an ant-plant network is presented with the aims of: (1) depicting its structural changes over a 20-year period; (2) detailing temporal variation in network topology, as revealed by nestedness and modularity analysis and other parameters (i.e. connectance, niche overlap); and (3) identifying long-term turnover in taxonomic structure (i.e. switches in ant resource use or plant visitor assemblages according to taxa). Fieldwork was carried out at La Mancha, Mexico, and ant-plant interactions were observed between 1989 and 1991, between 1998 and 2000, and between May 2010 and 2011. Occurrences of ants on extrafloral nectaries (EFNs) were recorded. The resulting ant-plant networks were constructed from qualitative presence-absence data determined by a species-species matrix defined by the frequency of occurrence of each pairwise ant-plant interaction. Network variation across time was stable and a persistent nested structure may have contributed to the maintenance of resilient and species-rich communities. Modularity was lower than expected, especially in the most recent networks, indicating that the community exhibited high overlap among interacting species (e.g. few species were hubs in the more recent network, being partly responsible for the nested pattern). Structurally, the connections created among modules by super-generalists gave cohesion to subsets of species that otherwise would remain unconnected. This may have allowed an increasing cascade-effect of evolutionary events among modules. Mutualistic ant-plant interactions were structured 20 years ago mainly by the subdominant nectarivorous ant species Camponotus planatus and Crematogaster brevispinosa, which monopolized the best extrafloral nectar resources and out-competed other species with broader feeding habits. Through time, these ants, which are

  2. Carbon isotope analysis in apple nectar beverages Análise isotópica do carbono em néctar de maçã

    Directory of Open Access Journals (Sweden)

    Ricardo Figueira

    2013-03-01

    Full Text Available The aims of this study were to use the isotope analysis method to quantify the carbon of C3 photosynthetic cycle in commercial apple nectars and to determine the legal limit to identify the beverages that do not conform to the safety standards established by the Brazilian Ministry of Agriculture, Livestock and Food Supply. These beverages (apple nectars were produced in the laboratory according to the Brazilian legislation. Adulterated nectars were also produced with an amount of pulp juice below the permitted threshold limit value. The δ13C values of the apple nectars and their fractions (pulp and purified sugar were measured to quantify the C3 source percentage. In order to demonstrate the existence of adulteration, the values found were compared to the limit values established by the Brazilian Law. All commercial apple nectars analyzed were within the legal limits, which enabled to identify the nectars that were in conformity with the Brazilian Law. The isotopic methodology developed proved efficient to quantify the carbon of C3 origin in commercial apple nectars.Os objetivos deste trabalho foram utilizar o método de análise isotópica para quantificar o carbono do ciclo fotossintético C3 em néctares de maçã comerciais e mensurar o limite de legalidade para identificar as bebidas em inconformidade com o Ministério da Agricultura, Pecuária e Abastecimento. Essa bebida foi produzida em laboratório, conforme a legislação brasileira. Também foram produzidos néctares adulterados com quantidade de suco polposo abaixo do permitido. Os δ13C dos néctares de maçã e de suas frações (polpa e açúcar purificado foram mensurados para quantificar a porcentagem de fonte C3. Para determinar a existência de adulteração, foi calculado o limite de legalidade de acordo com a legislação brasileira. Todos os néctares comerciais de maçã analisados foram classificados como legais. O limite de legalidade possibilitou identificar as bebidas

  3. 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

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

    Science.gov (United States)

    Salas-Arcos, Lucía; Ornelas, Juan Francisco

    2017-01-01

    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 hours

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

    Science.gov (United States)

    Salas-Arcos, Lucía; Lara, Carlos; Ornelas, Juan Francisco

    2017-01-01

    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. We investigated the floral biology, pollinator assemblages, breeding system and nectar production patterns of P. gentianoides inhabiting a temperate montane forest in central Mexico. Pollination experiments were also conducted to assess the pollinator effectiveness of bumblebees and hummingbirds. 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 hours. Hummingbirds made more foraging

  6. 蝴蝶蜜源与非蜜源植物挥发物成分的差异%Difference between nectar plants and non-nectar plants of butterfly in volatile components

    Institute of Scientific and Technical Information of China (English)

    张雯雯; 郑华; 张弘

    2011-01-01

    采用全自动热脱附-气相色谱/质谱(ATD-GC/MS)联用技术,对动态顶空密闭循环吸附捕集的蝴蝶蜜源植物马缨丹、马利筋及非蜜源植物缅栀子花的挥发物进行分析检测.结果表明,同为蝴蝶的蜜源植物,马利筋和马缨丹的挥发物成分的种类和含量都有差异.马缨丹的香气成分主要为萜烯类化合物(60%),而马利筋中醛类(33.72%)含量相对高些,烯烃含量约占11%,二者都含有少量的醇.作为蝴蝶的非蜜源植物,缅栀子花的挥发物中有一定量的肟类(24.99%)和腈类(5.34%),在马利筋和马缨丹中均未检测出这2种组分.%Fragrances from the nectar and non-nectar plants of butterfly were closely and circularly head-space sampled within adsorptive tubes, and analyzed by auto thermal-desorption gas chromatography and mass spectrometry (ATD-GC/MS). Results showed that the volatile components of Asclepias curassavica Linn. and Lantana camara were different in variety and coment. Terpenes (60%) were high contained in Lantana camara, and aldehydes (33.72%) were high contained in A. curassavica (24.99%), nitrile (5.34%) were detected in Plumeria rubra Linn. cv. acutifolia, but were not detected in A. curassavica and L. camara.

  7. The cost of hovering and forward flight in a nectar-feeding bat, Glossophaga soricina, estimated from aerodynamic theory

    DEFF Research Database (Denmark)

    Norberg, U M; Kunz, T H; Steffensen, J F;

    1993-01-01

    (Phyllostomidae), namely the use of kinematic and morphological data and aerodynamic theory to estimate the mechanical power requirements (power output) for hovering and horizontal forward flight. A hot-wire anemometer was used to measure induced velocity (the velocity of air accelerated by the wings) during...... power for hovering is 0.34 W or 32.4 W kg-1. The mechanical power required for horizontal forward flight, near the minimum power flight speed (4.2 ms-1) for a 0.0117 kg bat is 0.14 W (12.3 W kg-1), of which 0.10 W is aerodynamic power and 0.042 W is inertial power. Comparison with our results...... on metabolic power requirements estimated from nectar intake gives a mechanical efficiency of 0.15 for hovering flight and 0.11 for forward flight near the minimum power speed....

  8. A new species of nectar-feeding bat, genus Lonchophylla, from western Colombia and western Ecuador (Mammalia: Chiroptera: Phyllostomidae)

    Science.gov (United States)

    Woodman, N.

    2007-01-01

    The twelve recognized species of nectar-feeding bats of the genus Lonchophylla occur in low- and middle-elevation, humid, Neotropical forests. Morphological and morphometrical analyses of specimens formerly lumped with Lonchophylla mordax O. Thomas (1903) support recognition of Lonchophylla concava Goldman (1914) as a separate species and reveal a third species from the western Pacific lowlands of Colombia and Ecuador that I describe herein as Lonchophylla jornicata. This new species is morphologically similar to Lonchophylla concava but is distinctively larger than that species. Tests for sexual dimorphism within these and other species of Lonchophyllini suggest a tendency for females to have slightly longer, narrower skulls, higher coronoid processes of the mandible, and longer forearms than males.

  9. Optimal pollinator attraction strategies in Trollius ranunculoides Hemsl. (Ranunculaceae) at different altitudes: increased floral display or promotion of nectar output?

    Science.gov (United States)

    Ye, X-Q; Meng, J-L; Zhao, Z-G; Fan, B-L; Du, G-Z

    2011-05-01

    For alpine plant species, patterns of resource allocation to functional floral traits for pollinator attraction can be highly significant in adaptation to low pollinator abundance and consequent pollen limitation. Increased pollination can be achieved either through a larger floral display or production of more pollen rewards. In this study, variation in resource allocation to different components for pollinator attraction was studied along an altitudinal gradient in Trollius ranunculoides, an obligate self-incompatible out-crosser of the Qinghai-Tibet Plateau. We compared resource allocation to conspicuous yellow sepals (which mainly provide visual attraction) and degenerate petals (which provide the major nectar reward) between populations at four altitudes. Furthermore, we investigated the contribution of sepals and petals to pollinator attraction and female reproductive success in an experiment with sepal or petal removal at sites at different altitudes. At the level of single flowers, resource allocation increased to sepals but decreased to petals with increasing altitude. Consistent with these results, sepals contributed much more to visitation rate and seed set than petals, as confirmed in the sepal or petal removal experiment. Sepals and petals contributed to female reproductive success by ensuring visitation rate rather than visitation duration. To alleviate increasing pollen limitation with increasing altitude, resource allocation patterns of T. ranunculoides altered to favour development of sepals rather than petals. This strategy may improve pollination and reproductive success through visual attraction (sepal) rather than nectar reward (petal) over a gradient of decreasing pollinator abundance. © 2010 German Botanical Society and The Royal Botanical Society of the Netherlands.

  10. Chronic exposure of imidacloprid and clothianidin reduce queen survival, foraging, and nectar storing in colonies of Bombus impatiens.

    Science.gov (United States)

    Scholer, Jamison; Krischik, Vera

    2014-01-01

    In an 11-week greenhouse study, caged queenright colonies of Bombus impatiens Cresson, were fed treatments of 0 (0 ppb actual residue I, imidacloprid; C, clothianidin), 10 (14 I, 9 C), 20 (16 I, 17C), 50 (71 I, 39 C) and 100 (127 I, 76 C) ppb imidacloprid or clothianidin in sugar syrup (50%). These treatments overlapped the residue levels found in pollen and nectar of many crops and landscape plants, which have higher residue levels than seed-treated crops (less than 10 ppb, corn, canola and sunflower). At 6 weeks, queen mortality was significantly higher in 50 ppb and 100 ppb and by 11 weeks in 20 ppb-100 ppb neonicotinyl-treated colonies. The largest impact for both neonicotinyls starting at 20 (16 I, 17 C) ppb was the statistically significant reduction in queen survival (37% I, 56% C) ppb, worker movement, colony consumption, and colony weight compared to 0 ppb treatments. Bees at feeders flew back to the nest box so it appears that only a few workers were collecting syrup in the flight box and returning the syrup to the nest. The majority of the workers sat immobilized for weeks on the floor of the flight box without moving to fed at sugar syrup feeders. Neonicotinyl residues were lower in wax pots in the nest than in the sugar syrup that was provided. At 10 (14) ppb I and 50 (39) ppb C, fewer males were produced by the workers, but queens continued to invest in queen production which was similar among treatments. Feeding on imidacloprid and clothianidin can cause changes in behavior (reduced worker movement, consumption, wax pot production, and nectar storage) that result in detrimental effects on colonies (queen survival and colony weight). Wild bumblebees depending on foraging workers can be negatively impacted by chronic neonicotinyl exposure at 20 ppb.

  11. Chronic exposure of imidacloprid and clothianidin reduce queen survival, foraging, and nectar storing in colonies of Bombus impatiens.

    Directory of Open Access Journals (Sweden)

    Jamison Scholer

    Full Text Available In an 11-week greenhouse study, caged queenright colonies of Bombus impatiens Cresson, were fed treatments of 0 (0 ppb actual residue I, imidacloprid; C, clothianidin, 10 (14 I, 9 C, 20 (16 I, 17C, 50 (71 I, 39 C and 100 (127 I, 76 C ppb imidacloprid or clothianidin in sugar syrup (50%. These treatments overlapped the residue levels found in pollen and nectar of many crops and landscape plants, which have higher residue levels than seed-treated crops (less than 10 ppb, corn, canola and sunflower. At 6 weeks, queen mortality was significantly higher in 50 ppb and 100 ppb and by 11 weeks in 20 ppb-100 ppb neonicotinyl-treated colonies. The largest impact for both neonicotinyls starting at 20 (16 I, 17 C ppb was the statistically significant reduction in queen survival (37% I, 56% C ppb, worker movement, colony consumption, and colony weight compared to 0 ppb treatments. Bees at feeders flew back to the nest box so it appears that only a few workers were collecting syrup in the flight box and returning the syrup to the nest. The majority of the workers sat immobilized for weeks on the floor of the flight box without moving to fed at sugar syrup feeders. Neonicotinyl residues were lower in wax pots in the nest than in the sugar syrup that was provided. At 10 (14 ppb I and 50 (39 ppb C, fewer males were produced by the workers, but queens continued to invest in queen production which was similar among treatments. Feeding on imidacloprid and clothianidin can cause changes in behavior (reduced worker movement, consumption, wax pot production, and nectar storage that result in detrimental effects on colonies (queen survival and colony weight. Wild bumblebees depending on foraging workers can be negatively impacted by chronic neonicotinyl exposure at 20 ppb.

  12. Determination and Analysis of Free Amino Acids in Nectar Source of Armyworm Moth%黏虫蜜源植物花蜜中游离氨基酸的测定与分析

    Institute of Scientific and Technical Information of China (English)

    刘保玲; 王高平; 胡京枝

    2012-01-01

    为探讨黏虫成虫与迁飞中转地蜜源植物的营养关系,利用氨基酸分析仪测定了其蜜源植物油菜和紫云英花蜜中游离氨基酸的种类和含量.结果显示,油菜和紫云英花蜜中都含17种氨基酸,油菜花蜜中游离氨基酸的总含量是紫云英花蜜的2.47倍.紫云英花蜜与油菜花蜜中各游离氨基酸的含量不同.油菜花蜜中除胱氨酸、蛋氨酸、苯丙氨酸、赖氨酸、精氨酸外,其他游离氨基酸的含量均比紫云英花蜜中相应的氨基酸高,其中丙氨酸、酪氨酸、丝氨酸、甘氨酸、天冬氨酸的含量分别是紫云英花蜜的14.36倍、11.35倍、5.70倍、4.69倍、4.11倍.研究还发现,紫云英蜂蜜中氨基酸总量是紫云英花蜜中氨基酸总量的4.29倍,油菜花蜜比油菜蜂蜜多含了胱氨酸和亮氨酸.因此,不能用油菜蜂蜜、紫云英蜂蜜代替油菜花蜜、紫云英花蜜来研究紫云英和油菜花蜜对黏虫的营养效应.%Milk vetch(Astragalus sinicus)and rape(Brassica napus) arc primary nectar plants for oriental armyworm (Mythimna separata ). Milk vetch was reported as a key factor resulting in severe outbreaks of oriental armyworm in China. This study collected nectar of milk vetch and rape by the capillary method,and then determined the type and content of free amino acids by the ami-no acid analyzer. Results showed that there were 17 amino acids in both rape nectar and milk vetch nectar. The total free amino acid content in rape nectar was 2. 47 times as much as the content in milk vetch nectar. The content of each free amino acid was different between milk vetch nectar and rape nectar: The content in rape nectar was higher than that of the corresponding ami-no acid in milk vetch nectar except Cys,Met,Phe,Lys, Arg;The contents of Ala,Tys,Ser,Gly, and Asp in rape nectar were 14. 36,11. 35,5. 70,4, 69,and 4. 11 times as much as those in milk vetch nectar. The total free amino acid content in milk vetch honey was 4. 29

  13. Attributes of packing and intention for purchase towards orange juice and nectar /
    Atributos da embalagem e intenção de compra de suco e néctar de laranja

    OpenAIRE

    Sandra Helena Prudêncio; Valéria de Paula Rodrigues; Marta de Toledo Benassi; Marcela Tostes Frata

    2009-01-01

    The attributes of five packages of orange juice and orange nectar were evaluated by focus group and conjoint analysis techniques. The attributes and levels were identified such as brand name (well known and less known), price (high and low), information (“natural, “no food preservative”, “vitamin C-rich” and without information) and type of juice (juice and nectar), as being relevant to consumers purchase attitude. Eight packages images containing different combinations of the chosen attribut...

  14. Estudios morfo-anatómicos en nectarios florales y extraflorales de Triumfetta rhomboidea (Malvaceae, Grewioideae) Morpho-anatomical studies of the floral and extrafloral nectaries of Triumfetta rhomboidea (Malvaceae, Grewioideae)

    OpenAIRE

    Elsa Lattar; Stella Maris Solís; María M. Avanza; María Silvia Ferrucci

    2009-01-01

    La morfo-anatomía de los nectarios florales y extraflorales tricomáticos de Triumfetta rhomboidea Jacq. se estudió con microscopio óptico y microscopio electrónico de barrido. Las cinco glándulas nectaríferas florales, están localizadas en el androginóforo, mientras que los nectarios extraflorales se hallan en los márgenes de la base de la lámina en la hoja y en los márgenes de la bráctea. Las diferencias observadas entre ellos están dadas por el tamaño y la forma de las células epidérmicas b...

  15. Milkweed (Gentianales: Apocynaceae): a farmscape resource for increasing parasitism of stink bugs (Hemiptera: Pentatomidae) and providing nectar to insect pollinators and monarch butterflies.

    Science.gov (United States)

    Tillman, P G; Carpenter, J E

    2014-04-01

    In peanut-cotton farmscapes in Georgia, the stink bugs Nezara viridula (L.) and Chinavia hilaris (Say) (Hemiptera: Pentatomidae) and the leaffooted bug, Leptoglossus phyllopus (L.) (Hemiptera: Coreidae), disperse at crop-to-crop interfaces to feed on bolls in cotton. The main objective of this study was to determine whether insecticide-free tropical milkweed (Asclepias curassavica L.), a nectar-producing plant, can increase parasitism of these bugs by Trichopoda pennipes (F.) (Diptera: Tachinidae) and provide nectar to monarch butterflies and insect pollinators in these farmscapes. Peanut-cotton plots with and without flowering milkweed plants were established in 2009 and 2010. Adult T. pennipes, monarch butterflies, honey bees, and native insect pollinators readily fed on floral nectar of milkweed. Monarch larvae feeding on milkweed vegetation successfully developed into pupae. In 2009, N. viridula was the primary host of T. pennipes in cotton, and parasitism of this pest by the parasitoid was significantly higher in milkweed cotton (61.6%) than in control cotton (13.3%). In 2010, parasitism of N. viridula, C. hilaris, and L. phyllopus by T. pennipes was significantly higher in milkweed cotton (24.0%) than in control cotton (1.1%). For both years of the study, these treatment differences were not owing to a response by the parasitoid to differences in host density, because density of hosts was not significantly different between treatments. In conclusion, incorporation of milkweed in peanut-cotton plots increased stink bug parasitism in cotton and provided nectar to insect pollinators and monarch butterflies.

  16. Flight muscle enzymes and metabolic flux rates during hovering flight of the nectar bat, Glossophaga soricina: further evidence of convergence with hummingbirds.

    Science.gov (United States)

    Suarez, R K; Welch, K C; Hanna, S K; Herrera M, L G

    2009-06-01

    Given their high metabolic rates, nectarivorous diet, and ability to directly fuel their energetically-expensive flight using recently-ingested sugar, we tested the hypothesis that Pallas long tongued nectar bats (Glossophaga soricina) possess flight muscles similar to those of hummingbirds with respect to enzymatic flux capacities in bioenergetic pathways. In addition, we compared these biochemical capacities with flux rates achieved in vivo during hovering flight. Rates of oxygen consumption (V(O(2))) were measured during hover-feeding and used to estimate rates of ATP turnover, glucose and long-chain fatty acid oxidation per unit mass of flight muscle. Enzyme V(max) values at key steps in glucose and fatty acid oxidation obtained in vitro from pectoralis muscle samples exceed those found in the locomotory muscles of other species of small mammals and resemble data obtained from hummingbird flight muscles. The ability of nectar bats and hummingbirds to hover in fed and fasted states, fueled almost exclusively by carbohydrate or fat, respectively, allowed the estimation of fractional velocities (v/V(max)) at both the hexokinase and carnitine palmitoyltransferase-2 steps in glucose and fatty acid oxidation, respectively. The results further support the hypothesis of convergent evolution in biochemical and physiological traits in nectar bats and hummingbirds.

  17. Study on the Blueberry Hawthorn Nectar Process and Optimization for the Recipe%蓝莓山楂果茶的研制及配方的优化

    Institute of Scientific and Technical Information of China (English)

    汪慧华; 刘小飞; 汪长钢; 柳青; 徐雅君

    2014-01-01

    采用正交试验对蓝莓山楂果茶配方进行优化,确定稳定剂的配比及果茶的最佳配方,并通过不同杀菌条件比较其杀菌效果,优化果茶的杀菌参数。结果表明,果茶最佳的原料配方为:蓝莓与山楂混浆添加量为40%、白砂糖10%、柠檬酸0.08%、黄原胶0.03%和CMC0.03%。最佳杀菌时间和温度是85℃/20 min。%The paper reports the studies on the recipe optimization of blueberry hawthorn nectar, and ratios of stabilizers, the best ratios to the nectar components with an orthogonal statistical test method. By comparison with sterilization effects of various sterilization conditions, the optimization parameters are found. The results of the studies point out that the optimized ratios to nectar raw recipe are composed of a dosage of 40%blueberry and hawthorn mixing solutions, 10%sugar, 0.08%citric acid, 0.03%xanthan gum and 0.03%CMC. The best sterilization time and temperature is 85℃and 20 min.

  18. Comparisons of Nectar Quantity and Sugar Concentration of Pomegranate Blossom in a Day%石榴花全天泌蜜量和糖浓度研究

    Institute of Scientific and Technical Information of China (English)

    余玉生; 卢焕仙; 宋文菲; 张祖芸; 张学文

    2013-01-01

    [Objective] The airn was to research the rules of nectar quantity and sugar concentration of perfect and staminate flowers in a day.[Method] Based on nine Tianguang Yan pomegranate trees,nectar quantity and sugar concentration of perfect and staminate flowers were measured and analyzed in morning and afternoon.[Result] Average nectar quantity and sugar concentration differed insignificantly in morning and aftemoon of perfect flowers,which could also be applied to staminate flowers.However,average nectar quantity of perfect flower was 64.09 μl and of staminate flower was 44.07 μl.It is obvious that the two were of extremely significant differences (t=4.642,P<0.01),and the former was significantly higher by 45.43%.On the other hand,average sugar concentration of perfect flower was 48.44% and of staminate flower was 37.16%.The two were of extremely significant differences and the former is higher by 30.36%,compared with the latter.These suggested that nectar quantity and sugar concentration would maintain unchanged in different periods for a day,if nectars are not consumed by pollinators,such as bees and butterflies.In the same period,nectar quantity and sugar concentration of perfect flowers were higher than those of staminate flowers.[Conclusion] The research provides references for benefits increase of bee farmers and fruit farmers,as well as exploration of bee pollination.%[目的]研究石榴完全花和雄花全天的泌蜜量和糖浓度的规律.[方法]以9棵甜光颜石榴为试验材料,分别对其完全花和雄花的上午和下午两个时段的泌蜜量和糖浓度进行测定,并比较两种花的泌蜜量和糖浓度.[结果]完全花上午时段和下午时段的平均泌蜜量及花蜜平均糖浓度差异均不显著;雄花不同时段的平均泌蜜量及糖浓度差异亦不显著.完全花平均泌蜜量为64.09 μl,雄花为44.07μl,二者间差异极显著(t=4.642,P<0.01),完全花平均泌蜜量显

  19. Black Currant Nectar Reduces Muscle Damage and Inflammation Following a Bout of High-Intensity Eccentric Contractions.

    Science.gov (United States)

    Hutchison, Alexander T; Flieller, Emily B; Dillon, Kimber J; Leverett, Betsy D

    2016-01-01

    This investigation determined the efficacy of black currant nectar (BCN) in reducing symptoms of exercise-induced muscle damage (EIMD). Sixteen college students were randomly assigned to drink either 16 oz of BCN or a placebo (PLA) twice a day for eight consecutive days. A bout of eccentric knee extensions (3 × 10 sets @ 115% of 1RM) was performed on the fourth day. Outcome measures included muscle soreness (subjective scale from 0 to 10) and blood markers of muscle damage (creatine kinase, CK), inflammation (interleukin-6, IL-6), and oxygen radical absorbance capacity (ORAC). Although there were no differences in reported soreness between groups, consumption of BCN reduced CK levels at both 48 (PLA = 82.13% vs. BCN = -6.71%, p = .042) and 96 h post exercise (PLA = 74.96% vs. BCN = -12.11%, p = .030). The change in IL-6 was higher in the PLA group (PLA = 8.84% vs. BCN = -6.54%, p = .023) at 24 h post exercise. The change in ORAC levels was higher in the treatment group (BCN = 2.68% vs. PLA = -6.02%, p = .039) at 48 h post exercise. Our results demonstrate that consumption of BCN prior to and after a bout of eccentric exercise attenuates muscle damage and inflammation.

  20. Determination of plasticisers and BPA in Sicilian and Calabrian nectar honeys by selected ion monitoring GC/MS.

    Science.gov (United States)

    Lo Turco, Vincenzo; Di Bella, Giuseppa; Potortì, Angela Giorgia; Tropea, Alessia; Casale, Ermina Katia; Fede, Maria Rita; Dugo, Giacomo

    2016-11-01

    Twenty-six plasticisers and bisphenol A (BPA) in 39 Sicilian and Calabrian nectar honeys of different botanical south Italian origin were determined by GC-MS. Di-(2-ethylhexyl)phthalate was the most abundant plasticiser in all samples, reaching up 202.7 ± 153.1 µg kg(-1), followed by di-butylphthalate with a concentration of 40.3 ± 9.3 µg kg(-1), whereas the concentration of the other phthalates varied from not detectable to 68.2 µg kg(-1). Trace levels of adipate, sebacate and BPA were not detected in any samples. Among the different floral origin honeys, di-ethylphthalate levels were above the limit of quantification (LOQ) in orange blossom, wildflower and chestnut honey samples. Among the honeys of different geographical origin, di-methylphthalate, di-butylphthalate and di-(2-ethylhexyl)phthalate concentrations were similar. Calabrian honeys showed levels of di-ethylphthalate always lower than the LOQ, moreover di-(2-methylpropyl)phthalate levels were lower than the Sicilian ones. On the contrary, in Sicilian honeys di-(2-methylpropyl)phthalate levels were higher and di-ethylphthalate was present in 37% of samples.

  1. Nectar intake rate is modulated by changes in sucking pump activity according to colony starvation in carpenter ants.

    Science.gov (United States)

    Falibene, Agustina; Josens, Roxana

    2008-05-01

    Dynamics of fluid feeding has been deeply studied in insects. However, the ability to vary the nectar-intake rate depending only on the carbohydrate deprivation has been clearly demonstrated only in Camponotus mus ants. When insect morphometry and fluid properties remain constant, changes in intake rate could only be attributed to variations in sucking pump activity. Previous records of the electrical activity generated during feeding in C. mus have revealed two different signal patterns: the regular (RP, frequencies: 2-5 Hz) and the irregular (IP, frequencies: 7-12 Hz). This work studies the mechanism underlying food intake-rate modulation in ants by analysing whether these patterns are involved. Behaviour and electrical activity generated by ants at different starvation levels were analysed during feeding on sucrose solutions. Ants were able to modulate the intake rate for a variety of sucrose concentrations (10, 40 and 60%w/w). The IP only occurred for 60% of solutions and its presence did not affect the intake rate. However, during the RP generated under the starved state, we found frequencies up to 7.5 Hz. RP frequencies positively correlated with the intake-rate for all sucrose concentrations. Hence, intake-rate modulation according to sugar deprivation is mainly achieved by the ant's ability to vary the pumping frequency.

  2. Flowering time of butterfly nectar food plants is more sensitive to temperature than the timing of butterfly adult flight.

    Science.gov (United States)

    Kharouba, Heather M; Vellend, Mark

    2015-09-01

    1. Variation among species in their phenological responses to temperature change suggests that shifts in the relative timing of key life cycle events between interacting species are likely to occur under climate warming. However, it remains difficult to predict the prevalence and magnitude of these shifts given that there have been few comparisons of phenological sensitivities to temperature across interacting species. 2. Here, we used a broad-scale approach utilizing collection records to compare the temperature sensitivity of the timing of adult flight in butterflies vs. flowering of their potential nectar food plants (days per °C) across space and time in British Columbia, Canada. 3. On average, the phenology of both butterflies and plants advanced in response to warmer temperatures. However, the two taxa were differentially sensitive to temperature across space vs. across time, indicating the additional importance of nontemperature cues and/or local adaptation for many species. 4. Across butterfly-plant associations, flowering time was significantly more sensitive to temperature than the timing of butterfly flight and these sensitivities were not correlated. 5. Our results indicate that warming-driven shifts in the relative timing of life cycle events between butterflies and plants are likely to be prevalent, but that predicting the magnitude and direction of such changes in particular cases is going to require detailed, fine-scale data.

  3. The integration of diet, physiology, and ecology of nectar-feeding birds La integración de la dieta, fisiología, y ecología en aves nectarívoras

    Directory of Open Access Journals (Sweden)

    TODD J. McWHORTER

    2000-09-01

    Full Text Available Balance between energy acquisition and expense is critical for the survival and reproductive success of organisms. Energy budgets may be limited by environmental factors as well as by animal design. These restrictions may be especially important for small endotherms such as hummingbirds, which have exceedingly high energy demands. Many nectar-feeding bird species decrease food intake when sugar concentration in food is increased. This feeding response can be explained by two alternative hypotheses: compensatory feeding and physiological constraint. The compensatory feeding hypothesis predicts that if birds vary intake to maintain a constant energy intake to match energy expenditures, then they should increase intake when expenditures are increased. Broad-tailed hummingbirds (Selasphorus platycercus and Green-backed fire crown hummingbirds (Sephanoides sephaniodes were presented with diets varying in energy density and exposed to various environmental temperatures. Birds decreased volumetric food intake in response to sugar concentration. However, when they were exposed to lower environmental temperatures, and hence increased thermoregulatory demands, they did not increase their rate of energy consumption and lost mass. These results support the existence of a physiological constraint to the energy budgets of hummingbirds. Digestive and peripheral organ function limitations may impose severe challenges to the energy budgets of these small endotherms, and therefore play a significant role in determining their distribution, ecology, and natural history.El balance entre la adquisición y el uso de energía es crítico para la reproducción y sobrevivencia. Los presupuestos energéticos de los organismos pueden estar limitados tanto por factores ambientales como por su fisiología. Estas restricciones pueden ser especialmente importantes para pequeños endotérmos como los colibríes (picaflores que tienen costos energéticos altos por unidad de masa

  4. Morfologia de nectários em Leguminosae senso lato em áreas de caatinga no Brasil Nectary morphology of Leguminosae senso lato in areas of dry seasonal forest in Brazil

    Directory of Open Access Journals (Sweden)

    Yanna Melo

    2010-12-01

    Full Text Available Nectários extraflorais (Nefs são glândulas secretoras de néctar encontradas em diversas espécies de Angiospermas, inclusive Leguminosae. Essas estruturas podem se apresentar sob diferentes formas (elevados, embebidos; com ou sem estipe; cores distintas e posições nas plantas (na raque, no pecíolo, sendo essas características relevantes aos estudos de taxonomia e sistemática. Este trabalho analisou a diversidade morfológica dos Nefs em Leguminosae de uma área prioritária para a conservação da caatinga no Estado de Pernambuco. As 35 espécies de Legumionsae estudadas foram coletadas no Município de Mirandiba, no semi-árido Pernambucano, e submetidas às técnicas usuais para análise e descrição morfológica. Entre essas espécies, foram caracterizados Nefs com origem primária (não substitutivos e secundária (substitutivos. Dois diferentes tipos com onze formatos distintos foram encontrados entre elas. Uma grande variedade de localização, coloração, projeção, e dimensão foram registradas aqui. Uma chave de identificação e ilustrações foram elaboradas também. Os dados apresentados aqui ampliam o número de espécies estudadas com Nefs para a família, e também confirmam a importância taxonômica e ecológica dessas estruturas para os legumes da região do semi-árido do Brasil.Extrafloral nectaries (Efns are nectar secreting glands found in many species of Angiosperms, including Leguminosae. These structures have various forms (elevated, embedded; stalk present or not; different colors and positions on the plants (on the rachis, on the petiole, and these characteristics are relevant to taxonomy and morphology studies. This work analyses the morphological diversity of Efns in Leguminosae from a priority conservation area of caatinga in Pernambuco state. The 35 Leguminosae species studied were collected in Mirandiba municipality, a semi-arid region of Pernambuco and submitted to the usual techniques of anatomy and

  5. An energetics-based honeybee nectar-foraging model used to assess the potential for landscape-level pesticide exposure dilution

    Directory of Open Access Journals (Sweden)

    Johannes M. Baveco

    2016-08-01

    Full Text Available Estimating the exposure of honeybees to pesticides on a landscape scale requires models of their spatial foraging behaviour. For this purpose, we developed a mechanistic, energetics-based model for a single day of nectar foraging in complex landscape mosaics. Net energetic efficiency determined resource patch choice. In one version of the model a single optimal patch was selected each hour. In another version, recruitment of foragers was simulated and several patches could be exploited simultaneously. Resource availability changed during the day due to depletion and/or intrinsic properties of the resource (anthesis. The model accounted for the impact of patch distance and size, resource depletion and replenishment, competition with other nectar foragers, and seasonal and diurnal patterns in availability of nectar-providing crops and wild flowers. From the model we derived simple rules for resource patch selection, e.g., for landscapes with mass-flowering crops only, net energetic efficiency would be proportional to the ratio of the energetic content of the nectar divided by distance to the hive. We also determined maximum distances at which resources like oilseed rape and clover were still energetically attractive. We used the model to assess the potential for pesticide exposure dilution in landscapes of different composition and complexity. Dilution means a lower concentration in nectar arriving at the hive compared to the concentration in nectar at a treated field and can result from foraging effort being diverted away from treated fields. Applying the model for all possible hive locations over a large area, distributions of dilution factors were obtained that were characterised by their 90-percentile value. For an area for which detailed spatial data on crops and off-field semi-natural habitats were available, we tested three landscape management scenarios that were expected to lead to exposure dilution: providing alternative resources than

  6. Characters and phylogenetic relationships of nectar-feeding bats, with descriptions of new Lonchophylla from western South America (Mammalia: Chiroptera: Phyllostomidae: Lonchophyllini)

    Science.gov (United States)

    Woodman, N.; Timm, R.M.

    2006-01-01

    The Neotropical Lonchophyllini (Chiropter: Phyllostomidae) currently comprise four genera and thirteen species of nectar-feeding bats. These species often are separated into larger-bodied (eight species) and smaller-bodied (five species) forms to aid in identification. Our morphological and morphometrical analyses of the smaller Lonchophyllini revealed the existence of two distinctive, previously undescribed species of bats of the genus Lonchophylla from western South America. We describe a new form from Amazonian Peru as Lonchophylla pattoni and one from western Colombia as Lonchophylla cadenai. Phyllogenetic analysis of the Lonchophyllini based primarily on morphological characters indicates that these two new species are closely related to Lonchophylla thomasi.

  7. Estimated intake of the sweeteners, acesulfame-K and aspartame, from soft drinks, soft drinks based on mineral waters and nectars for a group of Portuguese teenage students.

    Science.gov (United States)

    Lino, C M; Costa, I M; Pena, A; Ferreira, R; Cardoso, S M

    2008-11-01

    In a survey of levels of acesulfame-K and aspartame in soft drinks and in light nectars, the intake of these intense sweeteners was estimated for a group of teenage students. Acesulfame-K was detected in 72% of the soft drinks, with a mean concentration of 72 mg l(-1) and aspartame was found in 92% of the samples with a mean concentration of 89 mg l(-1). When data on the content of these sweeteners in soft drinks were analysed according to flavour, cola drinks had the highest mean levels for both sweeteners with 98 and 103 mg l(-1) for acesulfame-K and aspartame, respectively. For soft drinks based on mineral water, aspartame was found in 62% of the samples, with a mean concentration of 82 mg l(-1) and acesulfame-K was found in 77%, with a mean level of 48 mg l(-1). All samples of nectars contained acesulfame-K, with a mean concentration of 128 mg l(-1) and aspartame was detected in 80% of the samples with a mean concentration of 73 mg l(-1). A frequency questionnaire, designed to identify adolescents having high consumption of these drinks, was completed by a randomly selected sample of teenagers (n = 65) living in the city of Coimbra, in 2007. The estimated daily intakes (EDI) of acesulfame-K and aspartame for the average consumer were below the acceptable daily intakes (ADIs). For acesulfame-K, the EDI was 0.7 mg kg(-1) bw day(-1) for soft drinks, 0.2 mg kg(-1) bw day(-1) for soft drinks based on mineral waters, and 0.5 mg kg(-1) bw day(-1) for nectars, representing 8.0%, 2.2%, and 5.8% of the ADI, respectively. A similar situation was observed for aspartame. In this way, the EDI for soft drinks was 1.1 mg kg(-1) day(-1), representing only 2.9% of the ADI. In respect of nectars, the EDI was 0.2 mg kg(-1) bw day(-1), representing 0.5% of the ADI. Soft drinks based on mineral waters showed the lowest EDI values of 0.3 mg kg(-1) bw day(-1), accounting for 0.7% of the ADI.

  8. Nectar feeding by the hovering hawk moth Macroglossum stellatarum: intake rate as a function of viscosity and concentration of sucrose solutions.

    Science.gov (United States)

    Josens, R B; Farina, W M

    2001-10-01

    Although nectar feeding in insects has long been studied, the knowledge of the effect of nectar energy content on the ingestion dynamics separately from the viscosity of the fluid is very limited. To determine the effects of both factors on the feeding behavior of the hovering hawk moth Macroglossum stellatarum, we developed a method to independently manipulate sucrose concentrations and viscosity. The intake rate was analyzed as a function of sucrose concentration, the concentration at constant viscosity (kept constant by adding tylose, an inert polysaccharide), and of the different viscosities of a 30% weight/weight (w/w) sucrose solution (by adding different amounts of tylose). By increasing the concentration, and thus its viscosity, the solution intake rate (in microl s (-1)) decreased beyond a 20% w/w sucrose solution. For a 30% sucrose solution, the intake rate decreased with increasing viscosity. At constant viscosity, the solution intake rate decreased beyond a 30% w/w sucrose solution. However, if we considered the quantity of sucrose ingested per unit time (sucrose intake rate), the same fitted maximum was attained for both series in which the sucrose concentration changed (33.6% w/w). Results suggest that the gustatory input affects the dynamics of fluid ingestion separately from the viscosity.

  9. 蜀葵花蜜成分与虫媒传粉模式的研究%Nectar Compositions and Insect Pollination of Althaea rosea

    Institute of Scientific and Technical Information of China (English)

    李群; 包琎龙; 王学英; 陈旭辉; 阮成江

    2011-01-01

    蜀葵(A lthaea rosea)是我国一种重要的传统花卉,其花具有雌雄异熟和雌雄异位两种特征,柱头能发生弯曲与自身花粉接触,存在潜在的延迟自交.为了检测蜀葵花蜜成分和观察访花昆虫的访花行为,在自然居群内观察蜀葵花期物候、访花昆虫种类及主要访花昆虫的访花行为,采用高效液相色谱法分析其花蜜的主要成分和含量.结果表明,蜀葵每株每天开放0~40朵花,平均具有23朵处于不同发育时期的花.蜀葵的花朵在开花前分泌花蜜,单花花期内花蜜分泌呈单峰曲线.花蜜含糖量为8.41%,共检测出14种氨基酸.访花昆虫13种,主要为意大利蜂(Apis mellifera),其访花频率与花开放时间和花蜜分泌的高峰时间一致.意大利蜂在同一植株上访花数超过1朵的访问比例约占66.04%.蜀葵内同株异花传粉导致的双亲近交不可避免,两性花中的雌雄异熟和雌雄异位的适应意义可能主要是避免雌雄干扰.%Hollyhock (Althaea rosea) is an important traditional flower of china. A combination of dichogamy and herkogamy in the flower, meanwhile, the stigmas can curve and contact its own pollen, indicating the potential of delayed selfing. In order to detect the composition of nectar and observe the behavior of visiting, the flowering phenology, the species and visiting behavior of flower-visiting insects on Althaea rosea were investigated in naturalized population. The nectar content was determined by high performance liquid chromatography and analyse the compositions. Each individual plant has an average of 23 flowers in different developmental stages ranging from 0 to 40. The nectar is secreted before flower opening and has a single-peak curve in anthesis. The content of sugar is 8.41% in nectars, and 14 amino acids are detected in them. There are 13 flowering-visiting species and Apis mellifera is the main pollinator, the visiting frequency of Apis mellifera is correlated with the

  10. EFNS guidelines on diagnosis and management of neuromyelitis optica

    DEFF Research Database (Denmark)

    Sellner, J; Boggild, M; Clanet, M;

    2010-01-01

    Neuromyelitis optica (NMO) or Devic's disease is a rare inflammatory and demyelinating autoimmune disorder of the central nervous system (CNS) characterized by recurrent attacks of optic neuritis (ON) and longitudinally extensive transverse myelitis (LETM), which is distinct from multiple sclerosis...

  11. EFNS guidelines on diagnosis and management of neuromyelitis optica

    DEFF Research Database (Denmark)

    Sellner, J; Boggild, M; Clanet, M

    2010-01-01

    Neuromyelitis optica (NMO) or Devic's disease is a rare inflammatory and demyelinating autoimmune disorder of the central nervous system (CNS) characterized by recurrent attacks of optic neuritis (ON) and longitudinally extensive transverse myelitis (LETM), which is distinct from multiple sclerosis...

  12. Chronic vagal stimulation for the treatment of low ejection fraction heart failure : results of the NEural Cardiac TherApy foR Heart Failure (NECTAR-HF) randomized controlled trial

    NARCIS (Netherlands)

    Zannad, Faiez; De Ferrari, Gaetano M; Tuinenburg, Anton E; Wright, David; Brugada, Josep; Butter, Christian; Klein, Helmut; Stolen, Craig; Meyer, Scott; Stein, Kenneth M; Ramuzat, Agnes; Schubert, Bernd; Daum, Doug; Neuzil, Petr; Botman, Cornelis; Castel, Maria Angeles; D'Onofrio, Antonio; Solomon, Scott D; Wold, Nicholas; Ruble, Stephen B

    2015-01-01

    AIM: The neural cardiac therapy for heart failure (NECTAR-HF) was a randomized sham-controlled trial designed to evaluate whether a single dose of vagal nerve stimulation (VNS) would attenuate cardiac remodelling, improve cardiac function and increase exercise capacity in symptomatic heart failure

  13. EFNS guidelines on the Clinical Management of Amyotrophic Lateral Sclerosis (MALS) - revised report of an EFNS task force.

    LENUS (Irish Health Repository)

    2012-02-01

    Background: The evidence base for the diagnosis and management of amyotrophic lateral sclerosis (ALS) is weak. Objectives: To provide evidence-based or expert recommendations for the diagnosis and management of ALS based on a literature search and the consensus of an expert panel. Methods: All available medical reference systems were searched, and original papers, meta-analyses, review papers, book chapters and guidelines recommendations were reviewed. The final literature search was performed in February 2011. Recommendations were reached by consensus. Recommendations: Patients with symptoms suggestive of ALS should be assessed as soon as possible by an experienced neurologist. Early diagnosis should be pursued, and investigations, including neurophysiology, performed with a high priority. The patient should be informed of the diagnosis by a consultant with a good knowledge of the patient and the disease. Following diagnosis, the patient and relatives\\/carers should receive regular support from a multidisciplinary care team. Medication with riluzole should be initiated as early as possible. Control of symptoms such as sialorrhoea, thick mucus, emotional lability, cramps, spasticity and pain should be attempted. Percutaneous endoscopic gastrostomy feeding improves nutrition and quality of life, and gastrostomy tubes should be placed before respiratory insufficiency develops. Non-invasive positive-pressure ventilation also improves survival and quality of life. Maintaining the patient\\'s ability to communicate is essential. During the entire course of the disease, every effort should be made to maintain patient autonomy. Advance directives for palliative end-of-life care should be discussed early with the patient and carers, respecting the patient\\'s social and cultural background.

  14. Pollination of Specklinia by nectar-feeding Drosophila: the first reported case of a deceptive syndrome employing aggregation pheromones in Orchidaceae.

    Science.gov (United States)

    Karremans, Adam P; Pupulin, Franco; Grimaldi, David; Beentjes, Kevin K; Butôt, Roland; Fazzi, Gregorio E; Kaspers, Karsten; Kruizinga, Jaco; Roessingh, Peter; Smets, Erik F; Gravendeel, Barbara

    2015-09-01

    The first documented observation of pollination in Pleurothallidinae was that of Endrés, who noticed that the 'viscid sepals' of Specklinia endotrachys were visited by a 'small fly'. Chase would later identify the visiting flies as being members of the genus Drosophila. This study documents and describes how species of the S. endotrachys complex are pollinated by different Drosophila species. Specimens of Specklinia and Drosophila were collected in the field in Costa Rica and preserved in the JBL and L herbaria. Flies were photographed, filmed and observed for several days during a 2-year period and were identified by a combination of non-invasive DNA barcoding and anatomical surveys. Tissue samples of the sepals, petals and labellum of Specklinia species were observed and documented by SEM, LM and TEM. Electroantennogram experiments were carried out on Drosophila hydei using the known aggregation pheromones ethyl tiglate, methyl tiglate and isopropyl tiglate. Floral compounds were analysed by gas chromatography-mass spectometry using those same pheromones as standards. Flowers of S. endotrachys, S. pfavii, S. remotiflora and S. spectabilis are visited and pollinated by several different but closely related Drosophila species. The flies are arrested by aggregation pheromones, including ethyl tiglate, methyl tiglate and isopropyl tiglate, released by the flowers, and to which at least D. hydei is very sensitive. Visible nectar drops on the adaxial surface of sepals are secreted by nectar-secreting stomata, encouraging male and female Drosophila to linger on the flowers for several hours at a time. The flies frequently show courtship behaviour, occasionally copulating. Several different Drosophila species can be found on a single Specklinia species. Species of the S. endotrachys group share a similar pollination syndrome. There seem to be no species-specific relationships between the orchids and the flies. It is not expected that Specklinia species will hybridize

  15. Defense mutualisms enhance plant diversification.

    Science.gov (United States)

    Weber, Marjorie G; Agrawal, Anurag A

    2014-11-18

    The ability of plants to form mutualistic relationships with animal defenders has long been suspected to influence their evolutionary success, both by decreasing extinction risk and by increasing opportunity for speciation through an expanded realized niche. Nonetheless, the hypothesis that defense mutualisms consistently enhance plant diversification across lineages has not been well tested due to a lack of phenotypic and phylogenetic information. Using a global analysis, we show that the >100 vascular plant families in which species have evolved extrafloral nectaries (EFNs), sugar-secreting organs that recruit arthropod mutualists, have twofold higher diversification rates than families that lack species with EFNs. Zooming in on six distantly related plant clades, trait-dependent diversification models confirmed the tendency for lineages with EFNs to display increased rates of diversification. These results were consistent across methodological approaches. Inference using reversible-jump Markov chain Monte Carlo (MCMC) to model the placement and number of rate shifts revealed that high net diversification rates in EFN clades were driven by an increased number of positive rate shifts following EFN evolution compared with sister clades, suggesting that EFNs may be indirect facilitators of diversification. Our replicated analysis indicates that defense mutualisms put lineages on a path toward increased diversification rates within and between clades, and is concordant with the hypothesis that mutualistic interactions with animals can have an impact on deep macroevolutionary patterns and enhance plant diversity.

  16. Plantas consideradas daninhas para culturas como fontes de néctar e pólen Plant species considered weeds as source of nectar and pollen

    Directory of Open Access Journals (Sweden)

    Mitzi Brandão

    1984-01-01

    Full Text Available São relacionadas 164 espécies de plantas consideradas danin has às culturas, no Estado de Minas Gerais, e que são produtoras de néctar e pólen. Essas plantas poderiam ser exploradas economicamente, visando o fornecimento de matéria prima a apicultura, e como fonte de alimento para os insetos polinizadores.There are related 164 species of weed plants of cultures in the state of Minas Gerais as source of nec tar and nectar and pollen. These plants could be used economically for the purpose of supply of raw material to the apiculture and as source of food for the pollination insects.

  17. Microbial Ecology of the Hive and Pollination Landscape: Bacterial Associates from Floral Nectar, the Alimentary Tract and Stored Food of Honey Bees (Apis mellifera)

    Science.gov (United States)

    Mott, Brendon M.; Maes, Patrick; Snyder, Lucy; Schwan, Melissa R.; Walton, Alexander; Jones, Beryl M.; Corby-Harris, Vanessa

    2013-01-01

    Nearly all eukaryotes are host to beneficial or benign bacteria in their gut lumen, either vertically inherited, or acquired from the environment. While bacteria core to the honey bee gut are becoming evident, the influence of the hive and pollination environment on honey bee microbial health is largely unexplored. Here we compare bacteria from floral nectar in the immediate pollination environment, different segments of the honey bee (Apis mellifera) alimentary tract, and food stored in the hive (honey and packed pollen or “beebread”). We used cultivation and sequencing to explore bacterial communities in all sample types, coupled with culture-independent analysis of beebread. We compare our results from the alimentary tract with both culture-dependent and culture-independent analyses from previous studies. Culturing the foregut (crop), midgut and hindgut with standard media produced many identical or highly similar 16S rDNA sequences found with 16S rDNA clone libraries and next generation sequencing of 16S rDNA amplicons. Despite extensive culturing with identical media, our results do not support the core crop bacterial community hypothesized by recent studies. We cultured a wide variety of bacterial strains from 6 of 7 phylogenetic groups considered core to the honey bee hindgut. Our results reveal that many bacteria prevalent in beebread and the crop are also found in floral nectar, suggesting frequent horizontal transmission. From beebread we uncovered a variety of bacterial phylotypes, including many possible pathogens and food spoilage organisms, and potentially beneficial bacteria including Lactobacillus kunkeei, Acetobacteraceae and many different groups of Actinobacteria. Contributions of these bacteria to colony health may include general hygiene, fungal and pathogen inhibition and beebread preservation. Our results are important for understanding the contribution to pollinator health of both environmentally vectored and core microbiota, and the

  18. 简述藏医药文化中的“甘露加持法”%Brief research on Nectar Offering in Tibetan medicine

    Institute of Scientific and Technical Information of China (English)

    达娃

    2011-01-01

    甘露加持法①是藏医药学文化的组成部分之一,有着千年的悠久历史,其仪式内容包含了西藏藏传佛教密宗的诸多内容.这一文化在不同历史发展过程中的不断完善,使之成了一门独特的理论体系.在查阅文献资料与咨询现有的几位年长的传承人的基础上,简要介绍甘露加持法的各项仪式内容,如所需的主要仪具、施法成员、施法过程等,以及其特征和意义.如今这一文化内容逐渐淡化,该文化面临着失传的危险.%As a part of the culture of Tibetan medicine,the Nectar Offering has a long history of a thousand year.There are some contents of Esoteric Sect in its ritual procedure.It was improved and established a special theory in the development.On the basic of literature research and investigating the senior inheritors,the contents of ritual procedure,including instrument,participants and procedure,its characteristics and significance were introduced.Nowadays,the culture of Nectar Offering is diluted gradually,and facing the danger of disappearing.

  19. Microbial ecology of the hive and pollination landscape: bacterial associates from floral nectar, the alimentary tract and stored food of honey bees (Apis mellifera.

    Directory of Open Access Journals (Sweden)

    Kirk E Anderson

    Full Text Available Nearly all eukaryotes are host to beneficial or benign bacteria in their gut lumen, either vertically inherited, or acquired from the environment. While bacteria core to the honey bee gut are becoming evident, the influence of the hive and pollination environment on honey bee microbial health is largely unexplored. Here we compare bacteria from floral nectar in the immediate pollination environment, different segments of the honey bee (Apis mellifera alimentary tract, and food stored in the hive (honey and packed pollen or "beebread". We used cultivation and sequencing to explore bacterial communities in all sample types, coupled with culture-independent analysis of beebread. We compare our results from the alimentary tract with both culture-dependent and culture-independent analyses from previous studies. Culturing the foregut (crop, midgut and hindgut with standard media produced many identical or highly similar 16S rDNA sequences found with 16S rDNA clone libraries and next generation sequencing of 16S rDNA amplicons. Despite extensive culturing with identical media, our results do not support the core crop bacterial community hypothesized by recent studies. We cultured a wide variety of bacterial strains from 6 of 7 phylogenetic groups considered core to the honey bee hindgut. Our results reveal that many bacteria prevalent in beebread and the crop are also found in floral nectar, suggesting frequent horizontal transmission. From beebread we uncovered a variety of bacterial phylotypes, including many possible pathogens and food spoilage organisms, and potentially beneficial bacteria including Lactobacillus kunkeei, Acetobacteraceae and many different groups of Actinobacteria. Contributions of these bacteria to colony health may include general hygiene, fungal and pathogen inhibition and beebread preservation. Our results are important for understanding the contribution to pollinator health of both environmentally vectored and core microbiota

  20. Studies on Optimization for the Compound Stabilizer Formulation of Hawthorn Blueberry Nectar%山楂蓝莓果茶复合稳定剂配方的优化

    Institute of Scientific and Technical Information of China (English)

    汪慧华; 罗红霞; 汪长钢; 刘小飞; 柳青

    2014-01-01

    In the studies, compound formulation stabilizers were tested to improve stabilization of hawthorn blueberry nectar in optimal conditions. An orthogonal statistical test method was used to compare its stability for experiments. As a result for the hawthorn blueberry nectar, the optimized stabilizer formulation was the ratios of sodium carboxymethyl cellulose(CMC) 0.02%, xanthan gum 0.03%, gelatin 0.03%in the component of stabilizers.%采用正交试验对山楂蓝莓果茶复合稳定剂配方进行优化,并进行稳定性比较实验,结果表明:最佳稳定剂配方为:羧甲基纤维素钠(CMC)0.02%、黄原胶0.03%、明胶0.03%。

  1. Benefits of blackberry nectar (Rubus spp.) relative to hypercholesterolemia and lipid peroxidation Beneficios del néctar de mora (Rubus spp.) en relación con la hipercolesterolemia y la peroxidación lipídica

    OpenAIRE

    P. R. Ferreira de Araujo; V. da Silva Santos; A. Rodrigues Machado; C. Gevehr Fernandes; J.A. Silva; R. da Silva Rodrigues

    2011-01-01

    Introduction: In humans, the normal metabolic activity produces free radicals that constantly, along with other risk factors, including hypercholesterolemia may be responsible for the onset of degenerative diseases. Some bioactive compounds present in blackberry (Rubus spp.) have the ability to act as natural antioxidants can make the food to minimize effects on the body caused by reactive oxygen species. Objective: This study verified the benefits of blackberry nectar through the quantificat...

  2. Multi-locus phylogenies of the genus Barteria (Passifloraceae) protray complex patterns in the evolution of myrmecophytism.

    NARCIS (Netherlands)

    Peccoud, J.; Piatscheck, F.; Yockteng, R.; Garcia, M.; Sauve, M.; Djieto-Lordon, C.; Harris, D.J.; Wieringa, J.J.; Breteler, F.J.; Born, C.; McKey, D.; Blatrix, R.

    2013-01-01

    The four species of the central African genus Barteria show variation in habitat and in degree of association with ants. Whereas B. solida, restricted to submontane forests, attracts opportunistic ants to extrafloral nectar, the three other species, found in lowland rainforests (B. fistulosa, B.

  3. Diel and Seasonal Activities of Culicoides spp. near Yankeetown, Florida.

    Science.gov (United States)

    1985-01-01

    or cotton soaked with a sucrose solution are used to feed individuals in the laboratory (Jones, 1966). Nectar of flowers, honey dew, extrafloral...R.V., A.E. Colwell, and D.K. McClusky. 1980. Studies of Culicoides occidentalis at Borax Lake, California. Proc. Papers Calif. Mosq. Vector Control

  4. 超高压对草莓果肉饮料的杀菌效果与品质影响%Effects of High Hydrostatic Pressure(HHP) Processing on Microbial Inactivation and Quality of Strawberry Nectar

    Institute of Scientific and Technical Information of China (English)

    许文文; 曹霞敏; 胡小松; 廖小军

    2011-01-01

    研究不同超高压条件(压力600MPa,保压时间分别为0、2、4、6、8、10min)对草莓果肉饮料的杀菌效果及600MPa、4min超高压处理前后草莓果肉饮料理化品质的变化。结果表明:在600MPa、4min的超高压条件下,草莓果肉饮料中的细菌、霉菌和酵母可全部被杀死,并且该处理前后草莓果肉饮料中的可溶性固形物、pH值、可滴定酸、颜色、总酚含量及抗氧化性均无显著性差异(P〉0.05),但VC含量损失9.2%、花青素含量损失20.6%;超高压处理后草莓果肉饮料中部分酯类成分损失,醇类物质种类及数量增加(P〈0.05),但仍保持草莓原有的特征风味。%The effects of high hydrostatic pressure(HHP)(600 MPa,0-10 min) on microorganism inactivation and quality of strawberry nectar were investigated.HHP treatment for 4 min was sufficient to inactivate total aerobic bacteria,molds and yeasts in strawberry nectar without significantly influencing the total soluble solid,pH,titratable acidity,color,total phenols and antioxidant activity of strawberry nectar(P〉0.05).However,the contents of vitamin C and anthocyanins in HHP-treated strawberry nectar were significantly decreased by 9.2% and 20.6% respectively.Moreover,the esters in strawberry nectar were significantly decreased and the alcohols increased(P〈0.05) after HHP treatment,but the aroma quality of strawberry nectar was better retained.

  5. Adição de extratos de Ginkgo biloba e Panax ginseng em néctares mistos de frutas tropicais Addition of Ginkgo biloba and Panax ginseng extracts to mixed tropical fruit nectars

    Directory of Open Access Journals (Sweden)

    Paulo Henrique Machado de Sousa

    2010-06-01

    Full Text Available O estudo objetivou desenvolver formulações de néctares mistos de frutas tropicais, acrescidos de diferentes concentrações de extratos de Ginkgo biloba, Panax ginseng e misturas de Ginkgo biloba e Panax ginseng, avaliar características sensoriais, físico-químicas e químicas dos néctares selecionados. As formulações dos néctares tiveram a seguinte composição de polpa: caju (Anacardium occidentale, 12,25%; manga (Mangifera indica L, 21%; e acerola (Malpighia emarginata D.C., 1,75%. Foram desenvolvidas diferentes formulações, com a adição dos extratos nas concentrações variando de 15 a 30 mg.100 mL-1 de néctar. A avaliação sensorial da impressão global, sabor e aroma foi feita por meio de teste de aceitação. Para as bebidas formuladas com Panax ginseng, somente o atributo sabor apresentou variação com o aumento da concentração do extrato. Para as bebidas acrescidas de Ginkgo biloba, observou-se um decréscimo linear para todos os atributos avaliados com o aumento da concentração do extrato. Para a mistura de extratos, não se observou variação das médias com o aumento da concentração dos extratos. Conclui-se que a adição de extrato de Panax ginseng até a concentração de 20 mg.100 mL-1 de néctar e a mistura dos extratos, em concentrações de 7,5 mg.100 mL-1 de néctar de cada extrato, apresentam boa aceitação sensorial. A adição dos extratos não afetou a composição química dos néctares que apresentaram quantidades elevadas de vitamina C, carotenoides, fenólicos totais e antocianinas.The objectives of this study were to develop formulations of mixed nectars of tropical fruits adding different concentrations of Ginkgo biloba, Panax ginseng, and a mixture of Ginkgo biloba and Panax ginseng extracts and to assess sensory, physicochemical, and chemical characteristics of selected nectars. The nectar formulations had the following pulp composition: cashew apple (Anacardium occidentale, 12.25%, mango

  6. Preparation of a Blended Fruit Nectar of Orange and Carrot%柑橘-胡萝卜复合果肉饮料的研制

    Institute of Scientific and Technical Information of China (English)

    郭明月; 张臻

    2014-01-01

    以柑橘、胡萝卜为主要原料,研制一种新型的复合果肉饮料,重点解决产品配方和悬浮稳定性问题。采用单因素实验和正交试验,产品最佳配方为柑橘浆12.5%、胡萝卜浆12.5%、蔗糖11%、柠檬酸0.15%;稳定剂的最佳组合为羧甲基纤维素(Carboxymethyl Cellulose,CMC)0.25%、黄原胶0.15%。在此配方下,产品口感好,稳定效果佳。%A new blended fruit nectar was made from orange and carrot as the main materials. The formula and suspension stability of the product were focused on, and single-factor and orthogonal experiments were carried out to determine the optimal formula as follows: orange pulp 12.5%, carrot pulp 12.5%, sugar 11% and citric acid 0.15%. The optimum stabilizer formula included CMC 0.25%and xanthan gum 0.15%. The product thus obtained was featured by a nice taste and good stability.

  7. Studies on the Stability of Apricot Nectar Beverage%新疆小白杏果汁饮料的稳定性研究

    Institute of Scientific and Technical Information of China (English)

    孟岳成; 鲍若晗; 陈杰; 叶安丹

    2012-01-01

    The stability of apricot nectar beverage made from concentrated apricot pulp produced in Sinkiang was studied. Single factor test and rotation-regression-orthogonal experiments were carried out to investigated the effect of different stabilizer on the stability of apricot beverage. The mathematical evaluation model was set up based on 3 main component indexes selectcd by principal component analysis with sedimentation, absorbance of supernatant, sensory assessment and viscosity as evaluating index, the compound stabilizer was optimized as pectin 0.35%o, gellan 0.18%o, xan-than 0.10%o.%以新疆浓缩小白杏浆还原加工成50%果肉型杏汁饮料,采用单因素和三元二次回归正交旋转组合实验.以离心沉淀率、上清液吸光度、感官稳定性和黏度为指标,评价不同稳定剂对杏汁的稳定效果.通过因子分析提取3个主成分指标,构建综合评价模型,筛选出最佳复配稳定剂组合为:果胶0.35%、结冷胶0.18%、黄原胶0.10‰.

  8. Ants at Plant Wounds: A Little-Known Trophic Interaction with Evolutionary Implications for Ant-Plant Interactions.

    Science.gov (United States)

    Staab, Michael; Fornoff, Felix; Klein, Alexandra-Maria; Blüthgen, Nico

    2017-09-01

    Extrafloral nectaries (EFNs) allow plants to engage in mutualisms with ants, preventing herbivory in exchange for food. EFNs occur scattered throughout the plant phylogeny and likely evolved independent from herbivore-created wounds subsequently visited by ants collecting leaked sap. Records of wound-feeding ants are, however, anecdotal. By surveying 38,000 trees from 40 species, we conducted the first quantitative ecological study of this overlooked behavior. Ant-wound interactions were widespread (0.5% of tree individuals) and occurred on 23 tree species. Interaction networks were opportunistic, closely resembling ant-EFN networks. Fagaceae, a family lacking EFNs, was strongly overrepresented. For Fagaceae, ant occurrence at wounds correlated with species-level leaf damage, potentially indicating that wounds may attract mutualistic ants, which supports the hypothesis of ant-tended wounds as precursors of ant-EFN mutualisms. Given that herbivore wounds are common, wound sap as a steadily available food source might further help to explain the overwhelming abundance of ants in (sub)tropical forest canopies.

  9. Estabilidade do néctar misto de cajá e umbu Stability of mixed cajá and umbu nectar

    Directory of Open Access Journals (Sweden)

    Rafaella de Andrade Mattietto

    2007-09-01

    Full Text Available As tendências do setor alimentício são ditadas pelo mercado consumidor e seu comportamento social. Atualmente, a busca por produtos saudáveis tem crescido e frutos exóticos estão sendo cada vez mais utilizados visando o fator inovação. O cajá e umbu são frutos bastante comercializados no Norte e Nordeste do Brasil e o desenvolvimento de produtos à base destes frutos mostra ser uma opção interessante, pelo sabor e pelas características de funcionalidade. Elaborou-se um néctar misto que foi submetido à pasteurização térmica (90 °C/60 s. O produto foi caracterizado físico-quimicamente e ao longo de três meses avaliou-se a estabilidade segundo análises microbiológicas, sensoriais e de pH, acidez total titulável, açúcares totais e redutores, taninos, carotenóides totais e cor. Os resultados indicaram uma boa aceitação em relação à impressão global (84,76% e intenção de compra (90,62%. O produto apresentou um valor energético de 68,16 kcal.100 g-1, sendo rico em taninos e boa fonte de vitamina C. O tratamento térmico empregado se mostrou eficiente até 60 dias de estocagem, após esse período, o néctar apresentou modificações nos açúcares, escurecimento e crescimento de fungos. Sensorialmente, isso refletiu na queda da aceitação e intenção de compra, com valores de 65,66 e 68,4%, respectivamente.The trends of the food industry are dictated by the consumer market and by its social behavior. Today, there is a growing demand for healthful food products, and exotic fruits are being used increasingly, aiming at the innovation. Cajá and umbu are tropical fruits widely commercialized in Brazil’s northern and northeastern regions and the development of products based on these fruits has proved an interesting option thanks to their flavor and functional characteristics. A mixed nectar of cajú and umbu was prepared and pasteurised at 90 °C/60 sec. The product was characterized physicochemically and its

  10. 大气CO2浓度升高对花蜜及传粉昆虫的影响%Effects of elevated carbon dioxide on nectar and pollinating insects

    Institute of Scientific and Technical Information of China (English)

    吴华; 嵇保中; 刘曙雯; 高江勇; 王国兴; 王彦

    2011-01-01

    植物依赖昆虫传授花粉,昆虫从植物获得花粉和花蜜作为食物,两者在漫长的进化过程中形成了密切的互惠共生关系.大量研究表明,CO2浓度升高对植物花蜜的产量和组成有显著的影响.CO2浓度增加后,有花植物花蜜的产量和组分在不同物种之间的变化差异很大,即使是种内不同基因型植株的花蜜对CO2浓度增加的反应也有所不同.大部分种类花蜜的产量会增加,也有些种类会减少.花蜜中糖类、氨基酸、次生代谢物质等的含量会有不同的改变,但花蜜的主要组分基本不发生变化.CO2浓度升高对访花昆虫的影响主要通过植物间接作用于昆虫.CO2浓度增加引起物候的改变以及花蜜总量、质量、次生代谢物的改变对传粉昆虫的能量分配、繁殖、寿命和访花行为产生了重要的影响.本文综述了国内外相关研究进展,并分析了未来研究趋势及其存在的问题.%Entomophilous flowers depend on the pollination of insects, and at the same time, plants provide pollen and honey as rewards. As a result, a co -evolution has been formed during their long evolutionary history. It has been well demonstrated that elevated CO2 in environment significantly affects concentration and composition of nectar. Once the CO2 concentration increases, production and components of nectar of different species could change differently even within different genotypes of the same species.At elevated CO2 level, nectar production increased, but composition of nectar did not affect significantly,meanwhile, total sugar, amino acids and secondary metabolites per flower changed on some degrees in some species of plants. Elevated CO2 affected pollinating insects indirectly. Changes of flowering phenology, and concentration and composition of secondary metabolites in nectar resulting from elevated CO2, affect energy distribution, reproduction, life longevity and collecting behavior of pollinators. In this

  11. 巴马神酒对小鼠补肾壮阳作用实验研究%Experimental Study on Kidney-yang Reinforcing Effect of Bama Nectar

    Institute of Scientific and Technical Information of China (English)

    林劲; 刘碧好; 欧阳辉; 周园; 梁春玲; 钟燕春; 周玖瑶

    2016-01-01

    Objective:To observe the effects of bama nectar in kidney-yang deficienct mice and on the mating ability and sperm counts of normal mice. Methods:The weight, body temperature, locomotor activity, cold-resistant,genital organ coefficient and lipid peroxidation of the hydrocortisone-induced kidney-yang deficient mice were detected. The genital organ ccoefficient, immune organ co-efficient and erectile function of the ovariectomized mice were detected. The mating ability and the sperm counts of normal mice were measured. Results:Compared with the model group, bama nectar obviously increased the weight, body temperature and locomotor ac-tivity of the hydrocortisone-induced kidney-yang deficient mice, and improved the locomotor activity, the organ coefficient of seminal vesicle, prostate gland, preputial gland and epididymis. Furthermore, bama nectar significantly increased the SOD activity in serum and reduced the level of MDA in serum when compared with the model group (P<0.05 or P<0.01). Compared with the model group, bama nectar could increase the organ coefficient of foreskin and thymus gland in the ovariectomized mice, and shorten the erec-tile latency (P<0. 05). Compared with the normal group, bama nectar improved the mating ability and the sperm counts of the male mice (P<0. 05 or P<0. 01). Conclusion:Bama nectar has beneficial effects on invigorating kidney and strengthening yang.%目的::观察巴马神酒对肾阳虚小鼠的影响,以及对正常小鼠交配能力及精子数量的影响。方法:观察巴马神酒对氢化可的松诱导的肾阳虚模型小鼠体重、体温、自主活动次数、耐寒能力、生殖器官脏器系数及抗脂质过氧化的影响,对去势性肾阳虚模型小鼠生殖器官脏器系数、免疫器官脏器系数及勃起功能的影响,以及对正常小鼠交配能力及附睾精子数量的影响。结果:巴马神酒能增加氢化可的松诱导的肾阳虚小鼠的体重、体温和自主活动次数,提

  12. Método de análise isotópica (δ13C e limite de legalidade em néctar de laranja Isotopic analysis (δ13C method and legal limit in orange nectar

    Directory of Open Access Journals (Sweden)

    Ricardo Figueira

    2011-09-01

    Full Text Available Os objetivos deste trabalho foram desenvolver o método de análise isotópica para quantificar o carbono do ciclo fotossintético C3 em néctares de laranja comerciais e mensurar o limite de legalidade, baseado na legislação brasileira, para identificar as bebidas que não estão em conformidade com o Ministério da Agricultura, Pecuária e Abastecimento (MAPA. As bebidas foram produzidas em laboratório, conforme a legislação brasileira. Também foram produzidos néctares adulterados com quantidade de suco de laranja abaixo do limite mínimo permitido pelo MAPA. Na análise isotópica, foi mensurado o enriquecimento isotópico relativo dos néctares de laranja e também de suas frações, sólidos insolúveis (polpa e açúcar purificado. Com esses resultados, foi estimada a quantidade de fonte C3 por meio da equação da diluição isotópica. Para determinar a existência de adulteração, foi necessária a criação do limite de legalidade de acordo com a legislação brasileira. Oito marcas comerciais de néctar de laranja foram analisadas. Todas foram classificadas como legais. O limite de legalidade foi uma importante inovação metodológica, que possibilitou identificar as bebidas que estavam em conformidade com a legislação brasileira. A metodologia desenvolvida provou ser eficiente para quantificar o carbono de origem C3 em néctares de laranja comerciais.This work aimed to develop the isotope analysis method to quantify the carbon of the C3 photosynthetic cycle in commercial orange nectars, and to measure the legal limit based on Brazilian legislation in order to identify beverages not conforming to the Ministry of Agriculture, Livestock and Food Supply (MAPA. The beverages were produced in a laboratory according to Brazilian law. Adulterated nectars were also produced with a pulpy juice quantity below the level permitted by MAPA. Isotope analyses measured the relative isotope enrichment of the orange nectars and also of their

  13. 韩国朝鲜时代“甘露帧”内容和风格之考察%On the Content and Style of Buddhist Paintings of Nectar Ritual in Korea

    Institute of Scientific and Technical Information of China (English)

    尹惠俊

    2012-01-01

    “甘露帧”即汉语中的“水陆画”,在韩国历史上曾经盛板一时,“甘露帧”分为上、中、下三坛结构。综合考察韩国现存“甘露帧”之图像内容,并分期对其风格论断,画面运用具有典型化特征。受画师的风格,地方风格因素的影响,多样的图像发展。其画面又不断形成新的画风。%"Buddhist paintings of Nectar Ritual" refers to "landscape painting" in Chinese and was once very popular in Korean history. Its frame is divided into three structures: upper, middle and bottom. Combining the Buddhist texts and theories, this paper studies the image content and styles of the existing Buddhist paintings of Nectar Ritual, aiming to explore the typification of screen using. The appearance of new images and disappearance of old images are influenced by many factors, such as the times, painter' s style and regional style. This diversification of image development formed a new painting style in the screen using.

  14. 蜜腺发达Ogura晚抽薹不结球白菜雄性不育系的鉴定%Evaluation of Late - bolting Ogura Chinese Cabbage Male Sterile Lines with Developed Nectar Gland

    Institute of Scientific and Technical Information of China (English)

    孙艳; 刘维信

    2011-01-01

    By comparing of bumble bee visiting and staying time on flowers of Ogura non - heading Chinese cabbage male sterile lines, two plants were identified and selected as they attracted more bumble bee visiting. Nectar gland size, flowering, and pod set of these two plants were further determined. The results showed that the two selected plants all had developed nectar glands, flowered and set pod normally. This finding set a well foundation for breeding out elite late -bolting Ogura male sterile lines in non -heading Chinese cabbage.%本试验以Ogura晚抽薹不结球白菜薹ms等为材料,通过观察和比较熊蜂对不同白菜品种访花次数和访花滞留时间的差异,选择出能吸引熊蜂访花且访花滞留时间长的Ogura薹ms植株.对选择出植株的蜜腺大小和开花结实特性进行了进一步鉴定,结果表明选出的薹ms株蜜腺发达,开花结实正常,为选育优良晚抽薹胞质不结球白菜雄性不育系奠定了基础.

  15. Correlation between the Change in the Number of Apis mellifera Worker Bees and Nectar Secretion of Nectariferous Plants%西方蜜蜂群势变化与蜜源植物泌蜜的关系研究

    Institute of Scientific and Technical Information of China (English)

    余玉生; 张祖芸; 宋文菲; 卢焕仙; 王艳辉

    2014-01-01

    [Objective] This study aimed to clarify the correlation between changes of Apis mel ifera and the nectar secretion characteristics of nectariferous plants. [Method] Considering the nectar secretion characteristics of major and auxiliary nec-tariferous plants, six Apis mel ifera colonies were selected for measure the number of eggs, larvae, pupae and adult bees from Jan. to Dec. in 2012; based on that, their annual change curves were also plotted. [Result] The results showed that there were three peaks of the total number of A. mel ifera workers throughout the year:the first occurred on May 15th, with bees developed into an ideal population for col-lecting pomegranate nectar, and the second and third peaks occurred on July 15th and Oct. 15th, respectively, with bees developed into an ideal population for col ect-ing E. ciliate (Thuab) Hyland. [Conclusion] Prevention of Varroa jacobsoni should be carried out with two or more types of acaricides at the late nectar flow stages of the two nectariferous plants(pomegranate and E. ciliate (Thuab) Hyland) when there was a nectar deficiency. Prevention of Tropilaelaps clareae should be timely per-formed with sublimed sulfur in conjunction with acaricides. This study provides a theoretical basis for the high-quality and high-yielding production of honey, as wel as for the product safety.%[目的]研究西方蜜蜂群势变化与蜜源植物泌蜜的关系。[方法]结合当地每年主要蜜源植物和辅助蜜源植物的泌蜜特点从2012年1月~12月选出6群西方蜜蜂进行周年卵虫量、封盖子量、成蜂量和总的群势量的测定,并据此分别绘出不同的周年变化曲线图和总的蜂群群势变化曲线图。[结果]全年蜂群繁殖达3个高峰。5月15日蜂群群势达到全年第1个高峰,正是采集石榴蜜源的理想蜂群。7月15日达全年第2个高峰,10月15日达全年第3个高峰,正是为采集野藿香蜜源发展的强群。[结论]防治大蜂螨应在两个主

  16. Benefits of blackberry nectar (Rubus spp. relative to hypercholesterolemia and lipid peroxidation Beneficios del néctar de mora (Rubus spp. en relación con la hipercolesterolemia y la peroxidación lipídica

    Directory of Open Access Journals (Sweden)

    P. R. Ferreira de Araujo

    2011-10-01

    Full Text Available Introduction: In humans, the normal metabolic activity produces free radicals that constantly, along with other risk factors, including hypercholesterolemia may be responsible for the onset of degenerative diseases. Some bioactive compounds present in blackberry (Rubus spp. have the ability to act as natural antioxidants can make the food to minimize effects on the body caused by reactive oxygen species. Objective: This study verified the benefits of blackberry nectar through the quantification of triglycerides, total and fraction cholesterol HDL (high density lipoprotein and LDL-cholesterol (low density lipoprotein, blood glucose and lipid peroxidation in hypercholesterolemic hamsters. Methods: Two groups were treated with hypercholesterolemic diets (0.1% cholesterol, one of them receiving an additional 5 mL of nectar daily, and a third (control group treated only with a standard diet. In the blood the quantification of lipids, blood glucose and lipid peroxidation was performed. In the brain, liver and small intestine the lipid peroxidation was determined and in other organs, histopathological evaluations were carried out. Results: The blackberry nectar reduced the triglycerides serum levels, total cholesterol and LDL-cholesterol in hypercholesterolemic hamsters, without influencing the HDL and blood glucose concentrations. A decrease in the initiation of lipid peroxidation reactions in the blood, brain and small intestine was also observed. Only the liver showed histopathological changes (steatosis, due to excess cholesterol, with no positive influence from the nectar.Introducción: En los seres humanos, la actividad metabólica normal produce radicales libres que constantemente, junto con otros factores de riesgo, incluyendo la hipercolesterolemia puede ser responsable de la aparición de enfermedades degenerativas. Algunos de los compuestos bioactivos presentes en mora (Rubus spp. tienen la capacidad de actuar como antioxidantes naturales

  17. 开花时间对巫山淫羊藿花蜜分泌和结实的影响%Effects of Flowering Period on Nectar Secretion and Fruit Set of Epimedium wushanense (Berberidaceae)

    Institute of Scientific and Technical Information of China (English)

    王怡; 权秋梅; 黎云祥

    2012-01-01

    The effect of flowering time on nectar secretion, effective pollinators activities and fruit set in Epimedium wushanense were revealed by One-way ANOVA. Among the three stage of flowering, the differences in nectar standing crop and sugar content of E. Wushanense were very remarkable. In this three populations, the nectar standing crop in the initial stage was higher than that in other stages, but the sugar content of nectar was higher in the last stage. The results indicated that the activities of effective pollinators were influenced by the flowering time significantly. During a day, the activities of effective pollinators were mainly concentrated in the noon. At the same time the visiting frequency of effective pollinators in last stage was higher than that in the initial and middle stage. It was also indicated that the fruit set, the seed number and percentage of seed abortion per fruit of E. Wushanense were influenced by the flowering time significantly. During the initial and the middle stage of flowering, the fruit set and the seed number per fruit were bigger than that in the last stage of flowering. But the percentage of seed abortion per fruit was higher in the last stage. So, in order to make work more effective, we should choose the fruits of E. Wushanense in the initial of flowering stage for experiments and breeding, and pay attention to the flowering regulation in artificial cultivation.%运用单因素方差分析研究了巫山淫羊藿(Epimedium wushanense)开花时间对花蜜分泌、有效传粉者活动及结实性的影响.结果表明:(1)开花时间对巫山淫羊藿花蜜常备量和含糖量的影响极其显著.3个种群早期花蜜常备量较高,而花蜜含糖量在晚期较高.(2)开花时间对有效传粉者行为也具显著影响.一天中,有效传粉者的访花活动主要集中在中午;在整个花期进程中,晚期有效访花频率明显大于早期.(3)开花时间对巫山淫羊藿结实率、果实种子数及果实

  18. Quality Changes of Strawberry Nectar Processed by Ultra High Pressure during Storage%超高压处理的草莓果肉饮料在贮藏过程中的品质变化

    Institute of Scientific and Technical Information of China (English)

    许文文; 曹霞敏; 刘凤霞; 廖小军

    2013-01-01

    The bacterial phase and qualities of strawberry nectar treated by ultra high pressure (600 MPa,4 min) at storage of 4 ℃ for seven months are studied. The experimental results show that there are no aerobic bacteria, yeasts or molds detected in the strawberry nectar during storage, from the microbial safety point of view, which indicates that ultra high pressure processing at 600 MPa for 4 min can be used as an alternative preservation method for extending its shelf life. No significant changes are observed for the total soluble solid content,pH value and titratable acidity during storage. However,the color gradually darkens,the contents of total phenols,vitamin C and anthocyanins significantly decrease (P<0. 05), and the DPPH (1 ,1-diphenyl-2-picrylhydrazyl) radical scavenging capacity and ferric reducing ability of plasma decrease (P<0. 05) with the prolongation of the storage period. In addition,the esters in the strawberry nectar significantly reduce,and the relative contents of the representative aromatic compounds including linalool and nerol in the strawberry nectar increase dramatically during the storage process (P<0. 05).%采用超高压处理(压力600 MPa、保压时间4 min)方法,实验研究了在4℃下储藏7个月时草莓果肉饮料的微生物及主要品质的变化.结果表明:草莓果肉饮料在7个月贮藏期内没有细菌、霉菌或酵母检出,仅从微生物角度看,超高压处理有效地延长了货架期;贮藏过程中草莓果肉饮料中的颜色逐渐变暗,可溶性固形物、pH值、可滴定酸有波动,但变化不显著(P>0.05),总酚、维生素C及花青素含量均逐渐减少,·DPPH(1,1-二苯基-2-三硝基苯肼)自由基清除能力及铁离子还原能力逐渐减弱;贮藏过程中草莓果肉饮料挥发性香气成分的种类和含量均发生明显变化,其中酯类成分显著降低,芳樟醇和反式-橙花叔醇随储藏时间的延长而显著增加.

  19. Effects of position on nectar secretion and fruit set of Epimedium wushanense%位置效应对巫山淫羊藿花蜜分泌和结实的影响

    Institute of Scientific and Technical Information of China (English)

    王怡; 黎云祥; 高辉; 权秋梅

    2013-01-01

    位置效应在开花植物中广泛存在。以野生巫山淫羊藿种群为研究对象,运用单因素方差分析法,研究位置效应对结实性和花蜜分泌的影响。结果表明:三个巫山淫羊藿种群不同位置的结实率显著差异,其中基部的结实率明显大于中部和顶部;位置效应对果实重量及果实长、宽的影响均显著,表现出基部>中部>顶部的趋势;总状花序上不同开花位置对单个果实种子数的影响显著,且基部大于顶部。但位置效应对单个果实种子败育率的影响不显著,均值呈现顶部>中部>基部变化规律;巫山淫羊藿不同开花位置的花蜜常备量和含糖量的差异显著。三个种群基部的花蜜常备量较高,而花蜜含糖量在顶部较高。因此,对巫山淫羊藿野生种群进行研究与保护时应注意位置效应对生殖成功的影响,选择基部果实进行试验或育种,应维持种群多样性及稳定性。%Position effect is a common phenomenon in flowering plant.In this experiment,we studied the position effect within inflorescence in Epimedium wushanense and researched the effects of different positions on reproductive success as well as nectar secretion using One-way ANOVA .The results indicated that the fruit set of E.wushanense was influenced by the different positions significantly.Among the three different positions,the fruit set of base fruit was significantly higher than that of top and middle fruit.Among these three positions of inflorescence,differences in fruit weight,fruit length and breadth were all significant,and for all base>middle>top.The seed number per fruit was influenced significantly by different positions of raceme,and base fruit have more seeds than top fruit.While the differences of the rate of seed abortion per fruit in different positions were not significant,though mean value showed top>middle>base.Nectar standing crop and sugar content were influenced by

  20. EFNS guidelines for the use of intravenous immunoglobulin in treatment of neurological diseases: EFNS task force on the use of intravenous immunoglobulin in treatment of neurological diseases

    DEFF Research Database (Denmark)

    Elovaara, I.; Apostolski, S.; Doorn, P. van

    2008-01-01

    ) and short-term treatment of severe MG (level A recommendation), and some paraneoplastic neuropathies (level B). IVIG is recommended as a second-line treatment in combination with prednisone in dermatomyositis (level B) and treatment option in polymyositis (level C). IVIG should be considered as a second...

  1. Ants visit nectaries of Epidendrum denticulatum (Orchidaceae in a Brazilian rainforest: effects on herbivory and pollination

    Directory of Open Access Journals (Sweden)

    A. M. Almeida

    Full Text Available Epidendrum denticulatum (Orchidaceae produces nectar on the petioles of buds, flowers, and fruits (extrafloral nectaries but no nectar is found on its flowers, and it is probably a deceptive species. In the Brazilian Atlantic rainforest, some aspects of both the ecology and behavior of Camponotus sericeiventris (Formicinae and Ectatomma tuberculatum (Ponerinae, two ant species foraging on E. denticulatum extrafloral nectaries, were investigated. Both experiments, using termites as baits and field observations, suggest that these ant species are able to prevent reproductive organ herbivory, without affecting pollinator behaviour. Since a low fruit set is often cited as a characteristic of the family, especially for deceptive species, ants attracted to orchid inflorescences protect reproductive structures and increase the probability of pollination success. Epidendrum denticulatum flowers were visited and probably pollinated by Heliconius erato (Nymphalidae and Euphyes leptosema (Hesperiidae.

  2. Ants visit nectaries of Epidendrum denticulatum (Orchidaceae in a Brazilian rainforest: effects on herbivory and pollination

    Directory of Open Access Journals (Sweden)

    Almeida A. M.

    2003-01-01

    Full Text Available Epidendrum denticulatum (Orchidaceae produces nectar on the petioles of buds, flowers, and fruits (extrafloral nectaries but no nectar is found on its flowers, and it is probably a deceptive species. In the Brazilian Atlantic rainforest, some aspects of both the ecology and behavior of Camponotus sericeiventris (Formicinae and Ectatomma tuberculatum (Ponerinae, two ant species foraging on E. denticulatum extrafloral nectaries, were investigated. Both experiments, using termites as baits and field observations, suggest that these ant species are able to prevent reproductive organ herbivory, without affecting pollinator behaviour. Since a low fruit set is often cited as a characteristic of the family, especially for deceptive species, ants attracted to orchid inflorescences protect reproductive structures and increase the probability of pollination success. Epidendrum denticulatum flowers were visited and probably pollinated by Heliconius erato (Nymphalidae and Euphyes leptosema (Hesperiidae.

  3. Methyl jasmonate induction of cotton: a field test of the 'attract and reward' strategy of conservation biological control.

    Science.gov (United States)

    Williams, Livy; Rodriguez-Saona, Cesar; Castle Del Conte, Sandra C

    2017-09-01

    Natural or synthetic elicitors can affect plant physiology by stimulating direct and indirect defence responses to herbivores. For example, increased production of plant secondary metabolites, a direct response, can negatively affect herbivore survival, development and fecundity. Indirect responses include increased emission of plant volatiles that influence herbivore and natural enemy behaviour, and production of extrafloral nectar that serves as a food source for natural enemies after their arrival on induced plants. Therefore, the use of elicitors has potential for the study of basic aspects of tritrophic interactions, as well as application in biorational pest control, i.e. an 'attract and reward' strategy. We conducted a field study to investigate the effects of methyl jasmonate, an elicitor of plant defence responses, on three trophic levels: the plant, herbivores and natural enemies. We made exogenous applications of methyl jasmonate to transgenic cotton and measured volatile emission, extrafloral nectar production and plant performance (yield). We also assessed insect abundance, insect performance, and parasitism and predation of brown stink bug, Euschistus servus, eggs in methyl jasmonate-treated and untreated control plots. Application of methyl jasmonate increased emission of volatiles, in particular, (+)-limonene and (3E)-4,8-dimethyl-1,3,7-nonatriene, and production of extrafloral nectar, but not yield, compared with the control treatment. Despite increased volatile and extrafloral nectar production, methyl jasmonate application did not affect plant bug performance, or mortality of E. servus egg masses, and only marginally influenced insect abundance. Mortality of E. servus eggs varied over the course of the study. Overall, methyl jasmonate treatment affected cotton plant-induced responses, but not the insects that inhabit the plants. Our results were probably influenced by reduced natural enemy colonization of cotton from adjacent non-crop habitats

  4. Proteção de Vochysia elliptica (Vochysiaceae) por uma formiga que rouba néctar

    OpenAIRE

    G. Q. ROMERO

    2002-01-01

    Vochysia elliptica (Vochysiaceae) is a shrubby plant, which does not have EFNs. Camponotus ants thieve nectar, and can decrease plant fitness by making flowers less attractive to pollinators. However, ants remove herbivores, wich can be beneficial. Results show that plants from which ants were excluded had lower rates of termite (simulated herbivore) removal than did plants visited by ants. Plants accessible to ants showed higher rates of termite removal in the base of leaves and in the inflo...

  5. Attributes of packing and intention for purchase towards orange juice and nectar / Atributos da embalagem e intenção de compra de suco e néctar de laranja

    Directory of Open Access Journals (Sweden)

    Sandra Helena Prudêncio

    2009-12-01

    Full Text Available The attributes of five packages of orange juice and orange nectar were evaluated by focus group and conjoint analysis techniques. The attributes and levels were identified such as brand name (well known and less known, price (high and low, information (“natural, “no food preservative”, “vitamin C-rich” and without information and type of juice (juice and nectar, as being relevant to consumers purchase attitude. Eight packages images containing different combinations of the chosen attributes were elaborated, according to a fractional factorial design (24-1. The images were evaluated, in terms of purchase intention, by 101 consumers. There was a segmentation of the consumers in three groups according to the similarity in the purchase behavior. The previous knowledge of the brand name, low price and the declarations of “natural”, “no food preservatives” and “vitamin C-rich” in the frontal part of the packing reveal to be important to improve the commercialization of the product.Atributos de cinco embalagens comerciais de suco e néctar de laranja foram avaliados por meio das técnicas grupos de foco e análise conjunta. Foram levantados os atributos e níveis, marca (muito conhecida e menos conhecida, preço (alto e baixo, declarações (“natural, sem conservantes, rico em vitamina C” e sem informação e tipo de bebida (suco e néctar, como relevantes na atitude de compra de consumidores. Elaboraram-se oito imagens de embalagens contendo diferentes combinações dos atributos levantados, obedecendo ao delineamento fatorial fracionado (24-1. As imagens foram avaliadas, quanto à intenção de compra, por 101 consumidores. Houve a segmentação dos consumidores em três grupos de acordo com a similaridade no comportamento de compra. O conhecimento prévio da marca, preço baixo e as declarações “natural”, “sem conservantes” e “rico em vitamina C” na face frontal da embalagem mostram-se importantes para a maior

  6. Trypanosoma evansi kDNA minicircle found in the Venezuelan nectar-feeding bat Leptonycteris curasoae (Glossophaginae), supports the hypothesis of multiple origins of that parasite in South America.

    Science.gov (United States)

    Silva-Iturriza, Adriana; Nassar, Jafet M; García-Rawlins, Ariany M; Rosales, Romel; Mijares, Alfredo

    2013-04-01

    Trypanosoma evansi is a mammal generalist protozoon which causes negative effects on health and productivity in bovine and equine herds in South America, Europe, Asia and Africa. By molecular methods, we screened the presence of that parasite together with other trypanosome species in 105 bats of 10 species collected in arid zones of northern Venezuela. The first molecular approach was fluorescent fragment length barcoding (FFLB), which relies on amplification of relative small regions of rRNA genes (four loci) and fluorescence detection. By FFLB, 17 samples showed patterns of possible trypanosomatid infections. These samples were used to test presence of trypanosomes by PCR using the following DNA markers: V7-V8 SSU rRNA, gGAPDH and kDNA minicircle regions. Only in one individual of the nectar-feeding bat, Leptonycteris curasoae, we were able to amplify 1000bp of the trypanosome kDNA minicircle. That PCR product was sequenced and the parasite species was determined by NCBI-BLAST and phylogenetic analysis. Both analyses showed that the minicircle sequence corresponds to Trypanosoma evansi. The phylogenetic analysis of the sequence obtained in this study clustered with a T. evansi sequence obtained in a Venezuelan capybara, Hydrochoerus hydrochaeris, and distant of others two T. evansi sequences obtained in a Colombian capybara and horse. This result supports the hypothesis of multiple origins of T. evansi in South America.

  7. EFNS review on the role of muscle biopsy in the investigation of myalgia

    DEFF Research Database (Denmark)

    Kyriakides, T; Angelini, Cinzia; Schaefer, J

    2013-01-01

    Myalgia, defined as any pain perceived in muscle, is very common in the general population and a frequent cause for referral to neurologists, rheumatologists and internists in general. It is however only rarely due to primary muscle disease and often referred from ligaments, joints, bones...

  8. Guidelines on routine cerebrospinal fluid analysis. Report from an EFNS task force

    DEFF Research Database (Denmark)

    Deisenhammer, F; Bartos, A; Egg, R

    2006-01-01

    A great variety of neurological diseases require investigation of cerebrospinal fluid (CSF) to prove the diagnosis or to rule out relevant differential diagnoses. The objectives were to evaluate the theoretical background and provide guidelines for clinical use in routine CSF analysis including...... be evaluated whenever pleocytosis is found or leptomeningeal metastases or pathological bleeding is suspected. Computed tomography-negative intrathecal bleeding should be investigated by bilirubin detection....

  9. EFNS/ENS Consensus on the diagnosis and management of chronic ataxias in adulthood

    NARCIS (Netherlands)

    Warrenburg, B.P.C. van de; Gaalen, J. van; Boesch, S.; Burgunder, J.M.; Durr, A.; Giunti, P.; Klockgether, T.; Mariotti, C.; Pandolfo, M.; Riess, O.

    2014-01-01

    BACKGROUND AND OBJECTIVES: The ataxias are a challenging group of neurological diseases due the aetiological heterogeneity and the complexity of the genetic subtypes. This guideline focuses on the heredodegenerative ataxias. The aim is to provide a peer-reviewed evidence-based guideline for clinical

  10. Analytical characteristics and discrimination of Brazilian commercial grape juice, nectar, and beverage Características analíticas e discriminação de suco, néctar e bebida de uva comerciais brasileiros

    Directory of Open Access Journals (Sweden)

    Luiz Antenor Rizzon

    2012-03-01

    Full Text Available The production and commercialization of Brazilian grape juice is increasing annually, mainly due to its typicality, quality, and nutritional value. The present research was carried out in view of the great significance of Brazilian grape juice for the grape and wine industry. The purpose of this study, therefore, was to assess its composition as well as the discrimination between grape juice and other beverages. Twenty four samples of whole, sweetened, and reprocessed grape juices, grape nectar, and grape beverage were evaluated. Classical variables were analyzed by means of physicochemical methods; tartaric and malic acids, by HPLC; methanol, by gas chromatography; minerals, by atomic absorption spectrophotometry. These products were discriminated by the Principal Component Analysis (PCA. Results show that whole and sweetened grape juices were discriminated from other grape products because they featured higher values of total soluble solids, tartaric and malic acids, most minerals, phenolic compounds, and K/Na ratio, whereas grape nectar and grape beverage presented higher values of ºBrix/titratable acidity ratio. Reprocessed juice was discriminated due to its higher concentrations of Li and Na and lower hue.A produção e a comercialização de suco de uva brasileiro estão aumentando anualmente devido a sua tipicidade, qualidade e valor nutritivo. Por isso, realizou-se este trabalho em face de sua importância para a agroindústria de vinho e de suco. O objetivo deste trabalho foi determinar a composição e discriminação do suco de uva em relação a outras bebidas dele derivadas. Avaliaram-se 24 amostras de sucos de uva −integral, adoçado e reprocessado −, néctar de uva e bebida de uva. As variáveis clássicas foram determinadas por meio de métodos físico-químicos; os ácidos tartárico e málico, por HPLC; o metanol, por cromatografia gasosa; e os minerais, por espectrofotometria de absorção atômica. Esses produtos foram

  11. Shifting butterfly habitats and biotope affiliations accompany use of alien nectar sources after deforestation%蝴蝶在生境和生物小区之间的移位伴随着对外来蜜源的利用

    Institute of Scientific and Technical Information of China (English)

    Peter B. HARDY; Roger L. H. DENNIS

    2008-01-01

    In the developed temperate world phytophagous insect communities are rapidly adjusting to introduced plants as larval food and nectar. In this study we investigate the readiness of butterfly species in a tropical context, experiencing relatively recent clear felling of forest, to use introduced flowering plants as nectar sources and the extent to which new butterfly-flowering plant assemblages are emerging in new biotopes. We find that introduced flowering plants are used by more species and more frequently by butterflies than native plants and that this relates to their ubiquity across sites and in biotopes and floral abundance. Moreover, distinctive assemblages of nectar-feeding butterfly species and flowering plants are associated with the emerging biotopes such as roadsides, subsistence cropland, intensive farmland, and gardens. In these new biotopes introduced plants are important in supplementing nectar resources for butterflies. We urge more intensive and detailed studies of wider resource use by native butterflies in tropical countries undergoing rapid change with deforestation to determine how butterflies are responding to emerging distinctive biotopes and the distinctive habitats, including consumer resources and utilities, these biotopes provide.%在发育成熟的温带环境中,植食性昆虫群落能迅速适应引入植物并将其作为幼虫的食物和花蜜.我们研究了经过森林砍伐的热带环境中蝴蝶对利用引入植物作为蜜源植物的适应快慢程度,并研究了蝴蝶-显花植物在新的生物小区中出现的范围,发现蝴蝶对引入显花植物的利用和探访多于本地植物,这与引入植物在调查地点、生物小区和植物丰度中的普遍性有关.此外,取食花蜜的蝴蝶和显花植物与正在形成的的生物小区有关,例如路边、农田、集约耕地以及花园.在这些新生物小区中,引入植物很重要,因为它们为蝴蝶提供了蜜源.

  12. Variação da concentração de vitamina C, ºBrix e acidez em néctar de laranja em embalagens cartonadas = Modification of vitamin C concentration, Brix and acidity in orange nectar in aseptic packaging

    Directory of Open Access Journals (Sweden)

    Telma Lucia de Oliveira

    2007-07-01

    Full Text Available Amostras de néctar de laranja, acondicionadas em embalagens cartonadas, foram armazenadas em local climatizado (25°C e em refrigerador (4°C. Durante oito semanas, análises de vitamina C, Brix e acidez foram realizadas no momento da abertura daembalagem, e seu produto residual foi ainda analisado durante quatro dias de estocagem em refrigerador. Analisando-se os resultados das variáveis por métodos estatísticos, observou-se que a temperatura de armazenagem influencia a quantidade de vitamina C do néctar delaranja. Ocorre decréscimo significativo na concentração de vitamina C, mas não há influência da temperatura de armazenagem no Brix e acidez do produto. O tempo de armazenamento influencia vitamina C, Brix e acidez. Constata-se, ainda, que após oito semanas de estocagem e quatro dias de abertura da embalagem a quantidade de vitamina C,em um copo de 200 mL do néctar de laranja estudado, supre a necessidade média diária de um adulto (60 mg.Samples of orange nectar in aseptic packaging were stored incontrolled room temperature (25°C and in a refrigerator (4°C. For eight weeks, analyses of vitamin C, Brix and acidity were conducted as the packages were opened, and their residual products were further analyzed during a period of four days stored in a refrigerator.By using statistical models from the results found, it was concluded that storage temperature influences the quantity of vitamin C in orange nectar. There was a significant decrease in vitamin C concentration in nectar, but storage temperature does not influenceacidity or Brix. Storage time does influence vitamin C, Brix and acidity. It was concluded that after eight weeks of storage and four days of opening the package, the amount of vitamin C in a 200 mL glass of orange nectar is enough to supply the average needed dailyintake (60 mg of vitamin C for an adult.

  13. Evidences that human disturbance simplify the ant fauna associated a Stachytarpheta glabra Cham. (Verbenaceae compromising the benefits of ant-plant mutualism

    Directory of Open Access Journals (Sweden)

    BC. Barbosa

    Full Text Available Interaction among species, like ants and plants through extrafloral nectaries (EFNs, are important components of ecological communities’ evolution. However, the effect of human disturbance on such specific interactions and its ecological consequences is poorly understood. This study evaluated the outcomes of mutualism between ants and the EFN-bearing plant Stachytarpheta glabra under anthropogenic disturbance. We compared the arthropod fauna composition between two groups of twenty plant individuals, one in an area disturbed by human activities and one in a preserved area. We also check the plant investment in herbivory defense and the consequential leaf damage by herbivore. Our results indicate that such disturbances cause simplification of the associated fauna and lack of proper ant mutualist. This led to four times more herbivory on plants of disturbed areas, despite the equal amount of EFN and ant visitors and low abundance of herbivores. The high pressure of herbivory may difficult the re-establishment of S. glabra, an important pioneer species in ferruginous fields, therefore it may affect resilience of this fragile ecological community.

  14. Evidences that human disturbance simplify the ant fauna associated a Stachytarpheta glabra Cham. (Verbenaceae) compromising the benefits of ant-plant mutualism.

    Science.gov (United States)

    Barbosa, B C; Fagundes, R; Silva, L F; Tofoli, J F V; Santos, A M; Imai, B Y P; Gomes, G G; Hermidorff, M M; Ribeiro, S P

    2015-01-01

    Interaction among species, like ants and plants through extrafloral nectaries (EFNs), are important components of ecological communities' evolution. However, the effect of human disturbance on such specific interactions and its ecological consequences is poorly understood. This study evaluated the outcomes of mutualism between ants and the EFN-bearing plant Stachytarpheta glabra under anthropogenic disturbance. We compared the arthropod fauna composition between two groups of twenty plant individuals, one in an area disturbed by human activities and one in a preserved area. We also check the plant investment in herbivory defense and the consequential leaf damage by herbivore. Our results indicate that such disturbances cause simplification of the associated fauna and lack of proper ant mutualist. This led to four times more herbivory on plants of disturbed areas, despite the equal amount of EFN and ant visitors and low abundance of herbivores. The high pressure of herbivory may difficult the re-establishment of S. glabra, an important pioneer species in ferruginous fields, therefore it may affect resilience of this fragile ecological community.

  15. Optimizing Crops for Biocontrol of Pests and Disease.

    Science.gov (United States)

    Stenberg, Johan A; Heil, Martin; Åhman, Inger; Björkman, Christer

    2015-11-01

    Volatile compounds and extrafloral nectar are common defenses of wild plants; however, in crops they bear an as-yet underused potential for biological control of pests and diseases. Odor emission and nectar secretion are multigene traits in wild plants, and thus form difficult targets for breeding. Furthermore, domestication has changed the capacity of crops to express these traits. We propose that breeding crops for an enhanced capacity for tritrophic interactions and volatile-mediated direct resistance to herbivores and pathogens can contribute to environmentally-friendly and sustainable agriculture. Natural plant volatiles with antifungal or repellent properties can serve as direct resistance agents. In addition, volatiles mediating tritrophic interactions can be combined with nectar-based food rewards for carnivores to boost indirect plant defense. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  16. Fitness Effects of Food Resources on the Polyphagous Aphid Parasitoid, Aphidius colemani Viereck (Hymenoptera: Braconidae: Aphidiinae).

    Science.gov (United States)

    Charles, Jennifer J; Paine, Timothy D

    2016-01-01

    Conservation biological control involving the polyphagous aphid parasitoid, Aphidius colemani Viereck, may include provisioning resources from a variety of plant sources. The fitness of adult A. colemani was enhanced with the provision of food resources such as floral nectar from a range of both native and introduced plant species and aphid honeydew under laboratory conditions. However, enhanced fitness appeared to be species specific rather than associated with the whether the plant was a native or an introduced species. Parasitoid survival and fecundity were enhanced significantly in response to the availability of floral nectar and honeydew compared to the response to available extrafloral nectar. These positive effects on the parasitoid's reproductive activity can improve the effectiveness of conservation biological control in nursery production systems because of the abundance and diversity of floral resources within typical production areas. Additionally, surrounding areas of invasive weeds and native vegetation could serve as both floral resources and honeydew food resources for A. colemani.

  17. Floração, produção de néctar e abelhas visitantes de Eriope blanchetii (Lamiaceae em dunas costeiras, Nordeste do Brasil Flowering, nectar production and visiting bees of Eriope blanchetii (Lamiaceae, in sand dunes, northeastern Brazil

    Directory of Open Access Journals (Sweden)

    Fabiana Oliveira da Silva

    2007-03-01

    Full Text Available As observações sobre a floração, produção de néctar e abelhas visitantes foram realizadas entre outubro de 1999 e outubro de 2000, em uma população natural de Eriope blanchetii (Benth Harley (Lamiaceae distribuída em dunas litorâneas, Salvador (12º56'S, 38º21'W, Bahia. Entre as 15 espécies de abelhas registradas, predominaram aquelas de porte corporal médio e grande. Os polinizadores efetivos são Xylocopa cearensis Ducke, 1910 e Colletes petropolitanus Dalla Torre, 1896, considerando seu tamanho, comportamento e freqüência nas flores. A floração contínua da população de E. blanchetii e o grau de sincronia, duração e intensidade da floração entre os indivíduos estimula o movimento interplanta e o transporte de pólen pelos polinizadores com diferentes demandas energéticas e comportamento generalista. A deposição de pólen ocorre na região ventral do corpo do polinizador na região que contata as anteras e o estigma durante o forrageio, mas apenas C. petropolitanus transportou exclusivamente pólen de E. blanchetii. O pólen, removido principalmente durante a fase masculina é, posteriormente, depositado em flores com estigmas receptivos durante a fase feminina. Entre maio e outubro de 2000, o volume de néctar variou de 0,01 a 0,98 ml sendo maior na fase masculina (U=2972,5; P0.05 e entre aquelas ensacadas e não ensacadas (U=3632; P>0.05 não foi significativa. O padrão de floração, a produção e acessibilidade do néctar tornam as flores de E. blanchetii atrativas aos seus polinizadores potenciais.Observations on nectar production, flowering and visiting bees were conducted from October 1999 to October 2000 in a wild population of Eriope blanchetii (Benth Harley (Lamiaceae located at Abaeté sand dunes (12º56'S, 38º21'W, in Salvador, Bahia. Fifteen bee species were collected with those varying from medium to large-sized being predominant. The effective pollinators were Xylocopa cearensis Ducke, 1910 and

  18. Five new records of ants (Hymenoptera: Formicidae) for Nebraska

    Science.gov (United States)

    Nemec, Kristine T.; Trager, James C.; Manley, Elizabeth; Allen, Craig R.

    2012-01-01

    Ants are ubiquitous and influential organisms in terrestrial ecosystems. About 1,000 ant species occur in North America, where they are found in nearly every habitat (Fisher and Cover 2007). Ants are critical to ecological processes and structure. Ants affect soils via tunneling activity (Baxter and Hole 1967), disperse plant seeds (Lengyel et al. 2009), prey upon a variety of insects and other invertebrates (Way and Khoo 1992, Folgarait 1998), are often effective primary consumers through their prodigious consumption of floral and especially extrafloral nectar, and honeydew (Tobin 1994), and serve as prey for invertebrates (Gotelli 1996, Gastreich 1999) and vertebrates (Reiss 2001).

  19. Methyl jasmonate induction of cotton: a field test of the ‘attract and reward’ strategy of conservation biological control

    Science.gov (United States)

    Rodriguez-Saona, Cesar; Castle del Conte, Sandra C

    2017-01-01

    Abstract Natural or synthetic elicitors can affect plant physiology by stimulating direct and indirect defence responses to herbivores. For example, increased production of plant secondary metabolites, a direct response, can negatively affect herbivore survival, development and fecundity. Indirect responses include increased emission of plant volatiles that influence herbivore and natural enemy behaviour, and production of extrafloral nectar that serves as a food source for natural enemies after their arrival on induced plants. Therefore, the use of elicitors has potential for the study of basic aspects of tritrophic interactions, as well as application in biorational pest control, i.e. an ‘attract and reward’ strategy. We conducted a field study to investigate the effects of methyl jasmonate, an elicitor of plant defence responses, on three trophic levels: the plant, herbivores and natural enemies. We made exogenous applications of methyl jasmonate to transgenic cotton and measured volatile emission, extrafloral nectar production and plant performance (yield). We also assessed insect abundance, insect performance, and parasitism and predation of brown stink bug, Euschistus servus, eggs in methyl jasmonate-treated and untreated control plots. Application of methyl jasmonate increased emission of volatiles, in particular, (+)-limonene and (3E)-4,8-dimethyl-1,3,7-nonatriene, and production of extrafloral nectar, but not yield, compared with the control treatment. Despite increased volatile and extrafloral nectar production, methyl jasmonate application did not affect plant bug performance, or mortality of E. servus egg masses, and only marginally influenced insect abundance. Mortality of E. servus eggs varied over the course of the study. Overall, methyl jasmonate treatment affected cotton plant-induced responses, but not the insects that inhabit the plants. Our results were probably influenced by reduced natural enemy colonization of cotton from adjacent non

  20. 蜜源植物常用农药对蜜蜂急性毒性及风险评价%The acute toxicity and risk assessment of 25 pesticides used in nectar plant to Apis mellifera L.

    Institute of Scientific and Technical Information of China (English)

    苍涛; 王彦华; 俞瑞鲜; 吴长兴; 陈丽萍; 吴声敢; 赵学平

    2012-01-01

    Twenty-five pesticides, which were commonly used in the period of flowering of 4 main nectar plants in Zhejiang province, were chosen to determine the acute toxicity to bees (Apis mellifera L. ) combining with the field maximum dose. The results showed that; the 48 h LC50 values of 1. 8% EC abamectin to Apis mellifera L. was 0. 0528 (0. 0462 -0. 0603) mg·L-1 , belongs to very high toxic grade; the 48 h LC50 values range of 1% EC em-amectin benzoate, 40% EC methidathion, 10% AS nitenpyram, 40% EC phoxim, 2.5% EC lambda-cyhalothrin, 4. 5% EC beta-cypermethrin, 480 g·L-1 EC chlorpyrifos, 45% EC malathion, 10% WP imidacloprid and 90% TC trichlorfon to Apis mellifera L. were 1. 02 (0. 869 - 1. 14) mg·L-1 to 13. 9 (12. 4 - 15. 5) mg·L-1, belongs to high toxic grade; the 48 h LC50 values range of 15% EC pyridaben, 20% SP acetamiprid and 15% WP ethylicin to Apis mellifera L. were 43. 3(37. 5 -50. 0) mg·L-1 to 163( 127 -210) mg-L ' , belongs to moderate toxic grade; the LC50 values of 5% SC fenpyroximate, 250 g·L-1 EC prochloraz, 25% WP diflubenzuron, 40% EC propargite, 50% WP cyromazine, 50% WG dimethomorph, 75% WG carbendazim, 25% WP buprofezin, 35% SC procymidone, 50% WP iprodione and 75% WP chlorothalonil to Apis mellifera L. were higher than 200 mg·L-1 , belongs to low toxic grade. The results showed that 1.8% EC abamectin, 1% EC emamectin benzoate, 40% EC methidathion, 10% AS nitenpyram, 40% EC phoxim, 2. 5% EC lambda-cyhalothrin, 4. 5% EC beta-cypermethrin, 480 g-L"1 EC chlorpyrifos, 45% EC malathion and 90% TC trichlorfon had very high risk to Apis mellifera L. 10% WP imidaclo-prid, 15% EC pyridaben and 5% SC fenpyroximate had high risk to Apis mellifera L. 20% SP acetamiprid, 15% WP ethylicin, 250 g·L-1 EC prochloraz, 40% EC propargite, 50% WP cyromazine and 50% WG dimethomorph were moderately risk to Apis mellifera L. , while other pesticides were low-risk to Apis mellifera L.%选择浙江省种植面积较大的4种蜜源植

  1. Caracterização física e química dos frutos da umbu-cajazeira (Spondias spp em cinco estádios de maturação, da polpa congelada e néctar Physical and chemical characterization on the fruits of umbu-cajazeira (Spondias spp in five ripening stages, frozen pulp and nectar

    Directory of Open Access Journals (Sweden)

    ELIZA DOROTEA POZZOBON DE ALBUQUERQUE LIMA

    2002-08-01

    Full Text Available A umbu-cajazeira, no Brasil, apresenta boas potencialidades de cultivo e perspectivas de comercialização, o que objetivou este trabalho de avaliação da qualidade física e química dos frutos em cinco estádios de maturação classificados de acordo com o grau de cor da casca descritos como: fruto totalmente verde (1FTV, frutos com início de pigmentação (2FIP, frutos parcialmente amarelos (3FPA, frutos totalmente amarelos (4FTA, frutos totalmente amarelo-alaranjados (5FTAA, da polpa congelada e do néctar. As variáveis estudadas foram os atributos físicos: peso, diâmetro longitudinal, diâmetro transversal e rendimento em polpa, e químicos: vitamina C, acidez total titulável sólidos solúveis totais, pH e a relação sólidos solúveis totais/acidez total titulável. Os frutos, no estádio de maturação comercial (4FTA, apresentaram os seguintes valores mé ;dio: rendimento de polpa de 55,75%; pH de 2,08; SST de 11,25 °Brix; ATT de 1,77 g de ácido citrico/100g de polpa; SST/ATT de 6,39 e teor de vitamina C total de 17,75 mg/100g. A polpa congelada e o néctar mantiveram-se em condições estáveis em relaç ;ão ao pH, SST, ATT e SST/ATT, durante 60 dias de armazenamento. Quanto ao teor de vitamina C total, a polpa congelada apresentou um decréscimo signi ficativo, o que não ocorreu com o néctar.In Brazil some tropical fruits present great potential for cultivation and perspective of commercialization, one of them is the "umbu-cajazeira". A research has been developed aiming to measure the physical and chemical quality of the frozen pulp and the nectar obtained from "umbu-cajazeira" fruits, which were classified in distinct maturation stages. The fruits were divided according to shell colour in five groups: fruit completely green (1FCG, fruit starting to change shell's colour (2FSCC, fruit partially yellow (3FPY, fruit totally yellow (4FTY, fruit totaly orange-like yellow. The variables analysed comprised the physical

  2. Determinação da formulação e caracterização do néctar de camu-camu (Myrciaria dubia McVaugh Formulation determination and characterisation of the camu-camu (Myrciaria dubia McVaugh nectar

    Directory of Open Access Journals (Sweden)

    Roberto N. Maeda

    2006-03-01

    Full Text Available O camu-camu é um fruto silvestre, encontrado nas margens de rios e lagos da Amazônia, com grande potencial econômico pelas suas características agronômicas, tecnológicas e nutricionais. Entretanto, seu consumo ainda é restrito, devido à alta acidez, amargor e adstringência da casca, necessitando, dessa forma, de tecnologias adequadas para o seu uso. O presente estudo teve por objetivo determinar a formulação ideal do néctar de camu-camu e avaliar as suas caraterísticas físicas e físico-químicas. Para a obtenção do néctar, foram elaboradas nove formulações com diferentes concentrações de polpa e açúcar, as quais foram submetidas ao teste de preferência de 30 provadores não treinados. Dentre as formulações testadas, a de maior preferência foi a preparada com 17,5% de açúcar e 17% de polpa, a qual apresentou valor de L Hunter de 32,00, aHunter de 3,22 e bHunter de -0,38, ácido ascórbico de 382,07 mg/100 mL, antocianinas de 2,51 mg/100 g e aceitabilidade global de 89,1%. Os resultados demonstram a viabilidade tecnológica e nutricional do néctar de camu-camu por ser um produto atraente de cor, sabor, aroma, aceitabilidade e como fonte de Vitamina C.Camu-camu is a wild fruit distributed throughout the banks of lakes and rivers in Amazonia, which presents a great economical potential on account of its agronomic, technological and nutritional features. Nevertheless, its consumption is still restricted due to its high acidity, bitterness, and skin astringency, thus needing the use of proper technologies for its use. The objective of the present study was to determine the ideal camu-camu nectar formulation and to assess its physical and physical-chemical characteristics. Nine formulations with different pulp and sugar concentrations, which were submitted to a preference test by a board of 30 untrained tasters, were prepared in order to obtain the nectar. Among the tested formulations, the one presenting the highest

  3. Sugar content in nectar flowers of siratro (Macroptilium atropurpureum Urb. - DOI: 10.4025/actascianimsci.v27i1.1248 Concentração de açúcares no néctar e visitantes florais do siratro (Macroptilium atropurpureum Urb. - DOI: 10.4025/actascianimsci.v27i1.1248

    Directory of Open Access Journals (Sweden)

    Renata Eunice Vieira

    2005-03-01

    Full Text Available Siratro (Macroptilium atropurpureum Urb. is a forager with high nutritional values and excellent palatability, and its phenology is almost unknown. Aiming at improving the knowledge and understanding siratro pollinators and floral biology, the total sugar contents on its flowers nectar and the identification of these sugars were determined by, respectively, spectrophotometry and chromatography. The total sugar concentration varied from a maximum of 1.36 and 3.23 mg/flower and a minimum of 0.19 and 0.42 mg/flower. Results showed that the total sugar concentration is high at 8:30 a.m., when the flowers open, and varies slightly during the time the flowers keep open. The variations can be related to the number of insects that visit the flowers, especially bees that may collect pollen and nectar during the open period (8:30 a.m. to 4:30 p.m.. Through enzymatic analysis, data showed that siratro has only glucose in its compositionSiratro (Macroptilium atropurpureum Urb. é uma planta forrageira com alto valor nutricional e excelente palatabilidade, sua fenologia é pouco conhecida. Objetivando melhorar o conhecimento e compreensão dos polinizadores do siratro e sua biologia floral, o conteúdo de açúcares totais no néctar de suas flores e a identificação desses açúcares foram determinados por espectrofotometria e cromatografia, respectivamente. A concentração de açúcares totais variou de 1,36 a 3,23 mg/flor para o valor máximo e de 0,19 a 0,42 mg/flor para o valor mínimo. Os resultados mostraram que a concentração de açúcares totais é alta às 8h30min, quando as flores estão abertas e varia um pouco durante o tempo que as flores permanecem abertas. A variação pode estar relacionada ao número de insetos que visitam as flores, especialmente as abelhas que podem coletar pólen e néctar durante o período de antese (8h30min às 16h30min. Por meio de análise enzimática, foi verificado que o siratro possui somente a glicose na sua

  4. SLAH3-type anion channel expressed in poplar secretory epithelia operates in calcium kinase CPK-autonomous manner.

    Science.gov (United States)

    Jaborsky, Mario; Maierhofer, Tobias; Olbrich, Andrea; Escalante-Pérez, María; Müller, Heike M; Simon, Judy; Krol, Elzbieta; Cuin, Tracey Ann; Fromm, Jörg; Ache, Peter; Geiger, Dietmar; Hedrich, Rainer

    2016-05-01

    Extrafloral nectaries secrete a sweet sugar cocktail that lures predator insects for protection from foraging herbivores. Apart from sugars and amino acids, the nectar contains the anions chloride and nitrate. Recent studies with Populus have identified a type of nectary covered by apical bipolar epidermal cells, reminiscent of the secretory brush border epithelium in animals. Border epithelia operate transepithelial anion transport, which is required for membrane potential and/or osmotic adjustment of the secretory cells. In search of anion transporters expressed in extrafloral nectaries, we identified PttSLAH3 (Populus tremula × Populus tremuloides SLAC1 Homologue3), an anion channel of the SLAC/SLAH family. When expressed in Xenopus oocytes, PttSLAH3 displayed the features of a voltage-dependent anion channel, permeable to both nitrate and chloride. In contrast to the Arabidopsis SLAC/SLAH family members, the poplar isoform PttSLAH3 is independent of phosphorylation activation by protein kinases. To understand the basis for the autonomous activity of the poplar SLAH3, we generated and expressed chimera between kinase-independent PttSLAH3 and kinase-dependent Arabidopsis AtSLAH3. We identified the N-terminal tail and, to a lesser extent, the C-terminal tail as responsible for PttSLAH3 kinase-(in)dependent action. This feature of PttSLAH3 may provide the secretory cell with a channel probably controlling long-term nectar secretion.

  5. How to prevent cheating: a digestive specialization ties mutualistic plant-ants to their ant-plant partners.

    Science.gov (United States)

    Kautz, Stefanie; Lumbsch, H Thorsten; Ward, Philip S; Heil, Martin

    2009-04-01

    Mutualisms often involve reciprocal adaptations of both partners. Acacia ant-plants defended by symbiotic Pseudomyrmex ant mutualists secrete sucrose-free extrafloral nectar, which is unattractive to generalists. We aimed to investigate whether this extrafloral nectar can also exclude exploiters, that is nondefending ant species. Mutualist workers discriminated against sucrose whereas exploiters and generalists with no affinity toward Acacia myrmecophytes preferred sucrose, because mutualist workers lacked the sucrose-cleaving enzyme invertase, which is present in workers of the other two groups. Sucrose uptake induced invertase activity in workers of parasites and generalists, but not mutualists, and in larvae of all species: the mutualists loose invertase during their ontogeny. This reduced metabolic capacity ties the mutualists to their plant hosts, but it does not completely prevent the mutualism from exploitation. We therefore investigated whether the exploiters studied here are cheaters (i.e., have evolved from former mutualists) or parasites (exploiters with no mutualistic ancestor). A molecular phylogeny demonstrates that the exploiter species did not evolve from former mutualists, and no evidence for cheaters was found. We conclude that being specialized to their partner can prevent mutualists from becoming cheaters, whereas other mechanisms are required to stabilize a mutualism against the exploitation by parasites.

  6. Amino Acids in Nectar Enhance Longevity of Female Culex quinquefasciatus

    Science.gov (United States)

    2010-01-01

    Culicidae) fed aqueous extracts of pollen. Annals of the Entomological Society of America 76, 661–663. Foster,W.A., 1995.Mosquito feeding and reproductive...different diets. Annals of the Entomological Society of America 53, 277–280. Martin, O.Y., Hosken, D.A., 2004. Copulation reduces male but not female...Verbenaceae]), Notorious weed and popular garden flower; some cases of poisoning in Florida. Economic Botany 48, 259–270. Nasci, R.S., 1991. Influence of

  7. 枣花蜜赋%Nectar of Chinese Date

    Institute of Scientific and Technical Information of China (English)

    徐鹏绪

    2010-01-01

    @@ 芒种前后,鲁西平原进入麦收季节.麦田一望无际,遍地金黄.村里村外的枣花也陆续开放.在阳光下闪亮的翠绿枣林,与金黄麦田交互辉映成一幅幅色彩明丽的图画;空气中飘散着悠悠的麦香和蜜香.催促播种的布谷鸟从空中掠过,留下一串串"布谷、布谷"的叫声,清脆、嘹亮而又悠长.

  8. Banana nectar as a medium for testing pollen viability and ...

    African Journals Online (AJOL)

    Administrator

    2007-05-16

    May 16, 2007 ... poor depend on bananas for food and cash income, a decline in banana .... The objectives of this study were (i) to compare the rate of banana pollen .... acuminata and M. balbisiana in Australia was given as. 71% and 98% ...

  9. 基于独立成分分析结合遗传算法的电子鼻蜜源检测特征信号挖掘%Analysis of feature signals of electronic nose in honey nectar detection based on independent components analysis combined with genetic algorithm

    Institute of Scientific and Technical Information of China (English)

    刘宁晶; 史波林; 赵镭; 庆兆珅; 籍保平; 周峰

    2015-01-01

    -nose in the honey nectar detection (rape honey, linden honey and acacia honey). However, in order to match the principle of ICA (each vector standing for one observing signal) and overcome the shortage of ICA (the randomness of independent components), some transforms of ICA are needed to be carried out. Referring to the methods applied in brain image analysis, the research extends the signals of different samples in time direction. In this case, the order of independent components was assured. After the comparison of different number of ICA, which is evaluated by the accuracy of pattern recognition with the support vector machine model, the optimum number is confirmed as 8. Although the quantity data has been narrowed down dramatically, still 960 points are included, 120 points for each components. To the further simplification, Genetic Algorithm (GA) is used to select the characteristic points to remove the redundant information. 20 points, many of which are located in the absorption phase are selected. The results of GA selection show that although most of special points are located in the absorption part, there are still a part of points which are emerged in desorption part. In this case, only selecting the values in the peak is defective, which may lead to the ignorance of some special information which is included in other parts, like the desorption part. To testify the effective of the method, it is compared with other common processing methods, including raw data without being processed, maximum conductance of the original signals, the Principle Components Analysis (PCA), and data only processed by ICA without GA. The data are processed by these five different processing methods. After that, the Support Vector Machine (SVM) is employed as the pattern recognition method. Compared with other models, SVM model is built based on the principle of structural risk minimization inductive principle, which takes the empirical risk and practical risk into account at the same

  10. Plant defense against insect herbivores

    DEFF Research Database (Denmark)

    Fürstenberg-Hägg, Joel; Zagrobelny, Mika; Bak, Søren

    2013-01-01

    defense responses. Plants also apply morphological features like waxes, trichomes and latices to make the feeding more difficult for the insects. Extrafloral nectar, food bodies and nesting or refuge sites are produced to accommodate and feed the predators of the herbivores. Meanwhile, herbivorous insects......Plants have been interacting with insects for several hundred million years, leading to complex defense approaches against various insect feeding strategies. Some defenses are constitutive while others are induced, although the insecticidal defense compound or protein classes are often similar....... Insect herbivory induce several internal signals from the wounded tissues, including calcium ion fluxes, phosphorylation cascades and systemic- and jasmonate signaling. These are perceived in undamaged tissues, which thereafter reinforce their defense by producing different, mostly low molecular weight...

  11. Ant plant herbivore interactions in the neotropical cerrado savanna

    Science.gov (United States)

    Oliveira, Paulo S.; Freitas, André V. L.

    2004-12-01

    The Brazilian cerrado savanna covers nearly 2 million km2 and has a high incidence on foliage of various liquid food sources such as extrafloral nectar and insect exudates. These liquid rewards generate intense ant activity on cerrado foliage, making ant plant herbivore interactions especially prevalent in this biome. We present data on the distribution and abundance of extrafloral nectaries in the woody flora of cerrado communities and in the flora of other habitats worldwide, and stress the relevance of liquid food sources (including hemipteran honeydew) for the ant fauna. Consumption by ants of plant and insect exudates significantly affects the activity of the associated herbivores of cerrado plant species, with varying impacts on the reproductive output of the plants. Experiments with an ant plant butterfly system unequivocally demonstrate that the behavior of both immature and adult lepidopterans is closely related to the use of a risky host plant, where intensive visitation by ants can have a severe impact on caterpillar survival. We discuss recent evidence suggesting that the occurrence of liquid rewards on leaves plays a key role in mediating the foraging ecology of foliage-dwelling ants, and that facultative ant plant mutualisms are important in structuring the community of canopy arthropods. Ant-mediated effects on cerrado herbivore communities can be revealed by experiments performed on wide spatial scales, including many environmental factors such as soil fertility and vegetation structure. We also present some research questions that could be rewarding to investigate in this major neotropical savanna.

  12. Mutualism exploitation: predatory drosophilid larvae sugar-trap ants and jeopardize facultative ant-plant mutualism.

    Science.gov (United States)

    Vidal, Mayra C; Sendoya, Sebastian F; Oliveira, Paulo S

    2016-07-01

    An open question in the evolutionary ecology of ant-plant facultative mutualism is how other members of the associated community can affect the interaction to a point where reciprocal benefits are disrupted. While visiting Qualea grandiflora shrubs to collect sugary rewards at extrafloral nectaries, tropical savanna ants deter herbivores and reduce leaf damage. Here we show that larvae of the fly Rhinoleucophenga myrmecophaga, which develop on extrafloral nectaries, lure potentially mutualistic, nectar-feeding ants and prey on them. Foraging ants spend less time on fly-infested foliage. Field experiments showed that predation (or the threat of predation) on ants by fly larvae produces cascading effects through three trophic levels, resulting in fewer protective ants on leaves, increased numbers of chewing herbivores, and greater leaf damage. These results reveal an undocumented mode of mutualism exploitation by an opportunistic predator at a plant-provided food source, jeopardizing ant-derived protection services to the plant. Our study documents a rather unusual case of predation of adult ants by a dipteran species and demonstrates a top-down trophic cascade within a generalized ant-plant mutualism. © 2016 by the Ecological Society of America.

  13. Sublethal effects of insecticide seed treatments on two nearctic lady beetles (Coleoptera: Coccinellidae).

    Science.gov (United States)

    Moscardini, Valéria Fonseca; Gontijo, Pablo Costa; Michaud, J P; Carvalho, Geraldo Andrade

    2015-07-01

    Predatory insects often feed on plants or use plant products to supplement their diet, creating a potential route of exposure to systemic insecticides used as seed treatments. This study examined whether chlorantraniliprole or thiamethoxam might negatively impact Coleomegilla maculata and Hippodamia convergens when the beetles consumed the extrafloral nectar of sunflowers grown from treated seed. We reared both species on eggs of Ephestia kuehniella and then switched adult H. convergens to a diet of greenbugs, Schizaphis graminum, in order to induce oviposition in this species. Excised sunflower stems, either treated or control and refreshed every 48 h, were provided throughout larval development, or for the first week of adult life. Exposure of C. maculata larvae to chlorantraniliprole and thiamethoxam applied as seed treatments delayed adult emergence by prolonging the pupal period. When adults were exposed, thiamethoxam reduced the preoviposition period compared to chlorantraniliprole, whereas the latter treatment cause females to produce fewer clutches during the observation period. Larvae of C. maculata did not appear to obtain sufficient hydration from the sunflower stems and their subsequent fecundity and fertility were compromised in comparison to the adult exposure experiment where larvae received supplemental water during development. Exposure of H. convergens larvae to thiamethoxam skewed the sex ratio in favor of females; both materials reduced the egg viability of resulting adults and increased the period required for eclosion. Exposure of H. convergens adults to chlorantraniliprole reduced egg eclosion times compared to thiamethoxam and exposure to both insecticides reduced pupation times in progeny. The results indicate that both insecticides have negative, sublethal impacts on the biology of these predators when they feed on extrafloral nectar of sunflower plants grown from treated seed.

  14. How plants sense wounds: damaged-self recognition is based on plant-derived elicitors and induces octadecanoid signaling.

    Directory of Open Access Journals (Sweden)

    Martin Heil

    Full Text Available BACKGROUND: Animal-derived elicitors can be used by plants to detect herbivory but they function only in specific insect-plant interactions. How can plants generally perceive damage caused by herbivores? Damaged-self recognition occurs when plants perceive molecular signals of damage: degraded plant molecules or molecules localized outside their original compartment. METHODOLOGY/PRINCIPAL FINDINGS: Flame wounding or applying leaf extract or solutions of sucrose or ATP to slightly wounded lima bean (Phaseolus lunatus leaves induced the secretion of extrafloral nectar, an indirect defense mechanism. Chemically related molecules that would not be released in high concentrations from damaged plant cells (glucose, fructose, salt, and sorbitol did not elicit a detectable response, excluding osmotic shock as an alternative explanation. Treatments inducing extrafloral nectar secretion also enhanced endogenous concentrations of the defense hormone jasmonic acid (JA. Endogenous JA was also induced by mechanically damaging leaves of lima bean, Arabidopsis, maize, strawberry, sesame and tomato. In lima bean, tomato and sesame, the application of leaf extract further increased endogenous JA content, indicating that damaged-self recognition is taxonomically widely distributed. Transcriptomic patterns obtained with untargeted 454 pyrosequencing of lima bean in response to flame wounding or the application of leaf extract or JA were highly similar to each other, but differed from the response to mere mechanical damage. We conclude that the amount or concentration of damaged-self signals can quantitatively determine the intensity of the wound response and that the full damaged-self response requires the disruption of many cells. CONCLUSIONS/SIGNIFICANCE: Numerous compounds function as JA-inducing elicitors in different plant species. Most of them are, contain, or release, plant-derived molecular motifs. Damaged-self recognition represents a taxonomically

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

    Directory of Open Access Journals (Sweden)

    P.S. Raju

    2014-09-01

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

  16. Integrating quality and quantity of mutualistic service to contrast ant species protecting Ferocactus wislizeni.

    Science.gov (United States)

    Ness, J H; Morris, W F; Bronstein, J L

    2006-04-01

    Generalized, facultative mutualisms are often characterized by great variation in the benefits provided by different partner species. This variation may be due to differences among species in the quality and quantity of their interactions, as well as their phenology. Many plant species produce extrafloral nectar, a carbohydrate-rich resource, to attract ant species that can act as "bodyguards" against a plant's natural enemies. Here, we explore differences in the quality and quantity of protective service that ants can provide a plant by contrasting the four most common ant visitors to Ferocactus wislizeni, an extrafloral nectary-bearing cactus in southern Arizona. The four species differ in abundance when tending plants, and in the frequency at which they visit plants. By adding surrogate herbivores (Manduca sexta caterpillars) to plants, we demonstrate that all four species recruit to and attack potential herbivores. However, their per capita effectiveness in deterring herbivores (measured as the inverse of the number of workers needed to remove half of the experimentally added caterpillars) differs. Using these among-species differences in quality (per capita effectiveness) and quantity (number of workers that visit a plant and frequency of visitation), we accurately predicted the variation in fruit production among plants with different histories of ant tending. We found that plant benefits (herbivore removal and maturation of buds and fruits) typically saturated at high levels of ant protection, although plants could be "well defended" via different combinations of interaction frequency, numbers of ant workers per interaction, and per capita effects. Our study documents variation among prospective mutualists, distinguishes the components of this variation, and integrates these components into a predictive measure of protection benefit to the plant. The method we used to average saturating benefits over time could prove useful for quantifying overall service in

  17. Food for Pollinators: Quantifying the Nectar and Pollen Resources of Urban Flower Meadows

    OpenAIRE

    Hicks, D.M.; Ouvrard, P.; Baldock, K.C.R.; Baude, M.; Goddard, M. A.; Kunin, W.E.; Mitschunas, N.; Memmott, J; Morse, H; Nikolitsi, M; Osgathorpe, L.M.; Potts, S. G.; Robertson, K. M.; Scott, A.V.; Sinclair, F.

    2016-01-01

    Planted meadows are increasingly used to improve the biodiversity and aesthetic amenity value of urban areas. Although many ‘pollinator-friendly’ seed mixes are available, the floral resources these provide to flower-visiting insects, and how these change through time, are largely unknown. Such data are necessary to compare the resources provided by alternative meadow seed mixes to each other and to other flowering habitats. We used quantitative surveys of over 2 million flowers to estimate t...

  18. Plasmodium falciparum infection increases Anopheles gambiae attraction to nectar sources and sugar uptake

    Science.gov (United States)

    Plasmodium parasites are known to manipulate the behaviour of their vectors so as to enhance their transmission. However, it is unknown if this vector manipulation also affects mosquito-plant interaction and sugar uptake. Dual-choice olfactometer and probing assays were used to study plant seeking b...

  19. Nectar and pollen feeding by insect herbivores and implications for multitrophic interactions

    NARCIS (Netherlands)

    Wäckers, F.L.; Romeis, J.; Van Rijn, P.C.J.

    2007-01-01

    Among herbivorous insects with a complete metamorphosis the larval and adult stages usually differ considerably in their nutritional requirements and food ecology. Often, feeding on plant structural tissue is restricted to the larval stage, whereas the adult stage feeds primarily or exclusively on p

  20. Do volatiles produced by nectar-dwelling microbes affect honey bee preferences?

    Science.gov (United States)

    The microbiome of plants mediates many interactions in natural and managed systems. Among these, plant-pollinator interactions are important for ensuring high crop yields, pollinator health and successful plant reproduction. Despite initial work demonstrating effects of floral microbes on pollinatio...

  1. Nectar and pollen feeding by insect herbivores and implications for multitrophic interactions

    NARCIS (Netherlands)

    Wäckers, F.L.; Romeis, J.; Van Rijn, P.C.J.

    2007-01-01

    Among herbivorous insects with a complete metamorphosis the larval and adult stages usually differ considerably in their nutritional requirements and food ecology. Often, feeding on plant structural tissue is restricted to the larval stage, whereas the adult stage feeds primarily or exclusively on p

  2. Why eat extra floral nectar? Understanding food selection by Coleomegilla maculata (Coleoptera: Coccinellidae)

    Science.gov (United States)

    The potential of omnivorous arthropods to stabilize ecosystems makes them an invaluable resource in biological control efforts. Methods of increasing predator abundance throughout agroecoystems include the incorporation of non-prey food items, yet the influence of this on predation rates remains un...

  3. 陕西猕猴桃蜜源%Nectar Plant Kiwifruit in SHAANXI Province

    Institute of Scientific and Technical Information of China (English)

    黎九洲; 张维力

    2011-01-01

    @@ 陕西省是猕猴桃的主产地,陕西省果业局2010年11月20日统计,全省猕猴桃面积已发展到4.254万hm2,总产量51.08万t,分别较上年增加1.065万hm2和近17万t,表明陕西猕猴桃面积和产量都已居全球第一.

  4. Nectar and Bee Stings%英译《花蜜与蜂刺》

    Institute of Scientific and Technical Information of China (English)

    朱凯丽

    2014-01-01

    蜂刺是蜜蜂最主要的武器。英译《花蜜与蜂刺》写了蜜蜂不仅仅因它辛勤酿蜜而获得赞美,而且因它蜂刺的巨大威力而获得赞美,更说明了蜜蜂英勇搏斗、视死如归的精神。

  5. Changes in sour cherry (Prunus cerasus L.) antioxidants during nectar processing and in vitro gastrointestinal digestion.

    NARCIS (Netherlands)

    Toydemir, G.; Capanoglu, E.; Kamiloglu, S.; Boyacioglu, D.; Vos, de C.H.; Hall, R.D.; Beekwilder, M.J.

    2013-01-01

    Sour cherry (Prunus cerasus L.) is rich in polyphenols, and like its processed products, is especially rich in anthocyanins. We have applied HPLC, spectrophotometric and on-line antioxidant detection methods to follow the fate of cherry antioxidants during an entire multi-step industrial-scale proce

  6. Juice and nectar consumer behaviour. Marketing research in cooperation with Pfanner, spol. s r. o.

    OpenAIRE

    Caisová, Alena

    2008-01-01

    In the theoretical part the thesis focus on consumer behavior and marketing research. Describes three models of buyer behaviour, main factors influencing the behaviour and the purchase decision-making proces. The second part of the thesis presents results of the primary marketing research.

  7. Comportamento de forrageio de Camponotus sericeiventris Guérin, 1838 (Hymenoptera, Formicidae em ambiente urbano

    Directory of Open Access Journals (Sweden)

    Thiago Elisei

    2012-07-01

    Abstract. Camponotus sericeiventris Guérin are described as omnivorous, their diet including floral and extrafloral nectar, exudates of hemipteran and lepidopteran, prey, seed and fruit foraged in the environment. The aim of this study was to examine the foraging behavior of C. sericeiventris, correlating the foraging activity and climatic factors as well as quantify and identify the resources exploited by the species and time of the foraging and action range. The specie studied was influenced positively by variations in the temperature. In most of the returns (94.81%, n = 7,072 the ants did not carry a load visible. Only 5.19% (n = 387 of the returns were identified and distributed as feces (35.40%, n = 137, animal protein (27.65%, n = 107 and vegetable fiber (36, 95%, n = 143. Two foraging trails, from colony to trees where ants were seeking resources, were measured (73 and 86 m representing an average of the distance of 79.5 ± 9.19 m, resulting in 19,596 m² of colony action. The duration of foraging of the C. sericeiventris had an average of 67 ± 16’97’’ (37’03’’- 101’ minutes. The results of this study provide important insights into understanding the dynamics of foraging activity of the C. sericeiventris in the human environment. Moreover, it shows the interaction of this specie with the environmental.

  8. Plant Defense against Insect Herbivores

    Science.gov (United States)

    Fürstenberg-Hägg, Joel; Zagrobelny, Mika; Bak, Søren

    2013-01-01

    Plants have been interacting with insects for several hundred million years, leading to complex defense approaches against various insect feeding strategies. Some defenses are constitutive while others are induced, although the insecticidal defense compound or protein classes are often similar. Insect herbivory induce several internal signals from the wounded tissues, including calcium ion fluxes, phosphorylation cascades and systemic- and jasmonate signaling. These are perceived in undamaged tissues, which thereafter reinforce their defense by producing different, mostly low molecular weight, defense compounds. These bioactive specialized plant defense compounds may repel or intoxicate insects, while defense proteins often interfere with their digestion. Volatiles are released upon herbivory to repel herbivores, attract predators or for communication between leaves or plants, and to induce defense responses. Plants also apply morphological features like waxes, trichomes and latices to make the feeding more difficult for the insects. Extrafloral nectar, food bodies and nesting or refuge sites are produced to accommodate and feed the predators of the herbivores. Meanwhile, herbivorous insects have adapted to resist plant defenses, and in some cases even sequester the compounds and reuse them in their own defense. Both plant defense and insect adaptation involve metabolic costs, so most plant-insect interactions reach a stand-off, where both host and herbivore survive although their development is suboptimal. PMID:23681010

  9. Predation success by a plant-ant indirectly favours the growth and fitness of its host myrmecophyte.

    Directory of Open Access Journals (Sweden)

    Alain Dejean

    Full Text Available Mutualisms, or interactions between species that lead to net fitness benefits for each species involved, are stable and ubiquitous in nature mostly due to "byproduct benefits" stemming from the intrinsic traits of one partner that generate an indirect and positive outcome for the other. Here we verify if myrmecotrophy (where plants obtain nutrients from the refuse of their associated ants can explain the stability of the tripartite association between the myrmecophyte Hirtella physophora, the ant Allomerus decemarticulatus and an Ascomycota fungus. The plant shelters and provides the ants with extrafloral nectar. The ants protect the plant from herbivores and integrate the fungus into the construction of a trap that they use to capture prey; they also provide the fungus and their host plant with nutrients. During a 9-month field study, we over-provisioned experimental ant colonies with insects, enhancing colony fitness (i.e., more winged females were produced. The rate of partial castration of the host plant, previously demonstrated, was not influenced by the experiment. Experimental plants showed higher δ(15N values (confirming myrmecotrophy, plus enhanced vegetative growth (e.g., more leaves produced increased the possibility of lodging ants in leaf pouches and fitness (i.e., more fruits produced and more flowers that matured into fruit. This study highlights the importance of myrmecotrophy on host plant fitness and the stability of ant-myrmecophyte mutualisms.

  10. Extensive variation in cadmium tolerance and accumulation among populations of Chamaecrista fasciculata.

    Directory of Open Access Journals (Sweden)

    Tessa M Henson

    Full Text Available Plant populations may vary substantially in their tolerance for and accumulation of heavy metals, and assessment of this variability is important when selecting species to use in restoration or phytoremediation projects. We examined the population variation in cadmium tolerance and accumulation in a leguminous pioneer species native to the eastern United States, the partridge pea (Chamaecrista fasciculata. We assayed growth, reproduction and patterns of cadmium accumulation in six populations of C. fasciculata grown on a range of cadmium-contaminated soils. In general, C. fasciculata exhibited tolerance in low to moderate soil cadmium concentrations. Both tolerance and accumulation patterns varied across populations. C. fasciculata exhibited many characteristics of a hyperaccumulator species, with high cadmium uptake in shoots and roots. However, cadmium was excluded from extrafloral nectar. As a legume with tolerance for moderate cadmium contamination, C. fasciculata has potential for phytoremediation. However, our findings also indicate the importance of considering the effects of genetic variation on plant performance when screening plant populations for utilization in remediation and restoration activities. Also, there is potential for cadmium contamination to affect other species through contamination of leaves, fruits, flowers, pollen and root nodules.

  11. Nectar intake of white-bellied sunbirds (Cinnyris talatala): can meal size be inferred from feeding duration?

    Science.gov (United States)

    Köhler, Angela; Verburgt, Luke; Nicolson, Sue W

    2008-01-01

    A positive relationship between feeding duration and meal size of avian nectarivores has often been assumed in earlier studies. We investigated whether feeding duration can be used as a surrogate for the amount of sugar solution ingested by white-bellied sunbirds, Cinnyris (Nectarinia) talatala. Feeding durations of sunbirds consuming three sucrose concentrations (10%, 20%, and 40% w/w) were measured using an infrared photodetection system, and the amounts consumed were recorded simultaneously by weighing the feeder throughout the experiment. For all three diet concentrations, a positive relationship was found between the time spent feeding per 30 min and the mass consumed. Therefore, feeding duration is demonstrated to be an index of the amount ingested on a particular sugar concentration. The rate of ingestion, however, depended on the sugar concentration, with the highest rate at the lowest concentration of 10% and the lowest rate at the 40% concentration. Less total time was spent feeding on the 20% solution than on the 10% solution, but time increased on the 40% diet because of viscosity effects. There appeared to be a weak relationship between feeding patterns and sex, but this was not significant, probably because of interindividual variation.

  12. A comparison of nectar- and honeydew sugars with respect to their utilization by the hymenopteran parasitoid Cotesia glomerata

    NARCIS (Netherlands)

    Wäckers, F.L.

    2001-01-01

    Fourteen naturally occurring sugars were individually tested with respect to their effect on Cotesia glomerata longevity. Parasitoids kept with solutions of either sucrose, glucose and fructose lived for >30 days. This constitutes a factor 15 increase in life span in comparison to control

  13. Introduction of coconut palm nectar with value added in the tourism región of Quintana Roo

    Directory of Open Access Journals (Sweden)

    Félix Rogelio Flores

    2008-03-01

    Full Text Available The coconut palm as consumption product has in other regions of the world an impact that could generate opportunities of economic growth in our country. To generate strategies of production, consumption and permanence of the coconut palm in the market, is a proposal that arises within the framework that INIFAP and Universidad de Colima and the School of Marketing beginning in 2006 up to this days. Through this document, is developing the main characteristics of the coconut palm, a proposal of standardization in the process of elaboration and pop marketing from the experiences obtained in Quintana Roo INIFAP research center and the marketing’s knowledge. Also are explained the processes which must be carried out for a similar process in any coconut region of Mexican country. This report is concluded with a model of competitiveness for the commercialization of the coconut palm.

  14. Assessing the risks and benefits of flowering field edges. Strategic use of nectar sources to boost biological control

    NARCIS (Netherlands)

    Winkler, K.

    2005-01-01

    The intensification of agricultural production systems during the last decades hadaenormous impact on the landscape structure in agro-ecosystems. Landscape elements like hedges andvegetationalrichfieldmargins

  15. Research on Rheological Property of Fragaria Nectar%草莓浆流变性的研究

    Institute of Scientific and Technical Information of China (English)

    陈钢; 王纪宁; 苏伟

    2006-01-01

    本文通过对不同温度、浓度和颗粒粒度下的草莓浆进行研究,发现草莓浆的表观粘度随浓度的增大而增大;随温度的升高而减小;而随着颗粒粒度的减小则出现先增大后减小的规律.

  16. 西蕃莲果浆的保鲜抗沉研究%Prevention of preciptation in passion fruit nectar

    Institute of Scientific and Technical Information of China (English)

    莫培芝

    2002-01-01

    西蕃莲果浆使用胶体磨研磨均质,添加果胶、阿拉伯胶等作为增稠稳定剂,添加异抗坏血酸钠或亚硫酸钠抗氧化变味,加糖冰结保存的工艺条件下,能够制成优秀的质地均一、无沉淀、无老化味、口感丰富鲜美的果浆.在冰结贮藏两年以上其风味、颜色没有改变.加入3%~8%果浆即可冲兑成西蕃莲果汁饮料.

  17. A new species of nectar-feeding bat, genus Lonchophylla, from the Caatinga of Brazil (Chiroptera, Phyllostomidae)

    OpenAIRE

    Ricardo Moratelli; Daniela Dias

    2015-01-01

    Abstract We describe Lonchophylla inexpectata sp. n. from the Caatinga of Brazil. This new species can be distinguished from all known species of Lonchophylla that occur in Brazil by dental traits, cranial size, and fur colour. Specimens of Lonchophylla inexpectata have been misidentified as Lonchophylla mordax ; but Lonchophylla inexpectata is a pale-venter species, similar in external appearance to Lonchophylla dekeyseri . We have found Lonchophylla inexpectata in the Caatinga of North-east...

  18. A new species of nectar-feeding bat, genus Lonchophylla, from the Caatinga of Brazil (Chiroptera, Phyllostomidae).

    Science.gov (United States)

    Moratelli, Ricardo; Dias, Daniela

    2015-01-01

    We describe Lonchophyllainexpectata sp. n. from the Caatinga of Brazil. This new species can be distinguished from all known species of Lonchophylla that occur in Brazil by dental traits, cranial size, and fur colour. Specimens of Lonchophyllainexpectata have been misidentified as Lonchophyllamordax; but Lonchophyllainexpectata is a pale-venter species, similar in external appearance to Lonchophylladekeyseri. We have found Lonchophyllainexpectata in the Caatinga of North-eastern Brazil; Lonchophyllamordax along the eastern border of the Caatinga and in the Atlantic Forest-Caatinga ecotone in North-eastern Brazil; and Lonchophylladekeyseri in the Cerrado of Mid-western Brazil, in the Brazilian Cerrado-Caatinga ecotone, and as far west as the Cerrado of Bolivia.

  19. Colony management in the nectar flow of eruca sativa%芸芥花期的蜂群管理

    Institute of Scientific and Technical Information of China (English)

    于先觉

    2010-01-01

    @@ 芸芥属于十字科,又叫芝麻菜,是一种旱生油料作物,高20~90厘米,花黄色后变白色,6~7月开花,花期一个多月.花的雄蕊基部有4个蜜腺,气温在28℃左右时流蜜最盛.蜜黄色,有充足的花粉,利于蜂群繁殖.

  20. A Novel EphA4-Based Small Molecule-Based Therapeutic Strategy for Prevention and Treatment of Post-Traumatic Osteoarthritis

    Science.gov (United States)

    2015-09-01

    direct injection of a soluble EphA4-acting EfnA-fc protein into the injured synovium. We will first confirm that EfnA-fc- mediated activation of the...strategy can prevent PTOA- mediated degradation of articular cartilage in early PTOA, and also can promote regeneration of articular cartilage in...promote regeneration of the damaged articular cartilage. In this project, we will first confirm that EfnA-fc- mediated activation of the forward

  1. Domacios y nectarios extraflorales en Bignoniáceas: componentes vegetales de una interacción mutualística Domatia and extrafloral nectaries in Bignoniaceae: two components of a mutualistic interaction

    OpenAIRE

    Gonzalez, Ana M.

    2011-01-01

    Las plantas presentan relaciones mutualísticas con insectos a cambio del control de sus herbívoros u hongos patógenos; por medio de los domacios les ofrecen albergue y mediante la secreción de néctar de nectarios extraflorales les brindan alimento. Se examinó la anatomía foliar en 52 especies de Bignoniaceae con microscopía óptica y electrónica de barrido, con el objetivo de describir los domacios y los nectarios extraflorales. Los domacios presentes son de dos tipos: mechones de pelos y bols...

  2. Few Ant Species Play a Central Role Linking Different Plant Resources in a Network in Rupestrian Grasslands.

    Science.gov (United States)

    Costa, Fernanda V; Mello, Marco A R; Bronstein, Judith L; Guerra, Tadeu J; Muylaert, Renata L; Leite, Alice C; Neves, Frederico S

    2016-01-01

    Ant-plant associations are an outstanding model to study the entangled ecological interactions that structure communities. However, most studies of plant-animal networks focus on only one type of resource that mediates these interactions (e.g, nectar or fruits), leading to a biased understanding of community structure. New approaches, however, have made possible to study several interaction types simultaneously through multilayer networks models. Here, we use this approach to ask whether the structural patterns described to date for ant-plant networks hold when multiple interactions with plant-derived food rewards are considered. We tested whether networks characterized by different resource types differ in specialization and resource partitioning among ants, and whether the identity of the core ant species is similar among resource types. We monitored ant interactions with extrafloral nectaries, flowers, and fruits, as well as trophobiont hemipterans feeding on plants, for one year, in seven rupestrian grassland (campo rupestre) sites in southeastern Brazil. We found a highly tangled ant-plant network in which plants offering different resource types are connected by a few central ant species. The multilayer network had low modularity and specialization, but ant specialization and niche overlap differed according to the type of resource used. Beyond detecting structural differences across networks, our study demonstrates empirically that the core of most central ant species is similar across them. We suggest that foraging strategies of ant species, such as massive recruitment, may determine specialization and resource partitioning in ant-plant interactions. As this core of ant species is involved in multiple ecosystem functions, it may drive the diversity and evolution of the entire campo rupestre community.

  3. Thermal tolerance affects mutualist attendance in an ant-plant protection mutualism.

    Science.gov (United States)

    Fitzpatrick, Ginny; Lanan, Michele C; Bronstein, Judith L

    2014-09-01

    Mutualism is an often complex interaction among multiple species, each of which may respond differently to abiotic conditions. The effects of temperature on the formation, dissolution, and success of these and other species interactions remain poorly understood. We studied the thermal ecology of the mutualism between the cactus Ferocactus wislizeni and its ant defenders (Forelius pruinosus, Crematogaster opuntiae, Solenopsis aurea, and Solenopsis xyloni) in the Sonoran Desert, USA. The ants are attracted to extrafloral nectar produced by the plants and, in exchange, protect the plants from herbivores; there is a hierarchy of mutualist effectiveness based on aggression toward herbivores. We determined the relationship between temperature and ant activity on plants, the thermal tolerance of each ant species, and ant activity in relation to the thermal environment of plants. Temperature played a role in determining which species interact as mutualists. Three of the four ant species abandoned the plants during the hottest part of the day (up to 40 °C), returning when surface temperature began to decrease in the afternoon. The least effective ant mutualist, F. pruinosus, had a significantly higher critical thermal maximum than the other three species, was active across the entire range of plant surface temperatures observed (13.8-57.0 °C), and visited plants that reached the highest temperatures. F. pruinosus occupied some plants full-time and invaded plants occupied by more dominant species when those species were thermally excluded. Combining data on thermal tolerance and mutualist effectiveness provides a potentially powerful tool for predicting the effects of temperature on mutualisms and mutualistic species.

  4. Few Ant Species Play a Central Role Linking Different Plant Resources in a Network in Rupestrian Grasslands

    Science.gov (United States)

    Mello, Marco A. R.; Bronstein, Judith L.; Guerra, Tadeu J.; Muylaert, Renata L.; Leite, Alice C.; Neves, Frederico S.

    2016-01-01

    Ant-plant associations are an outstanding model to study the entangled ecological interactions that structure communities. However, most studies of plant-animal networks focus on only one type of resource that mediates these interactions (e.g, nectar or fruits), leading to a biased understanding of community structure. New approaches, however, have made possible to study several interaction types simultaneously through multilayer networks models. Here, we use this approach to ask whether the structural patterns described to date for ant-plant networks hold when multiple interactions with plant-derived food rewards are considered. We tested whether networks characterized by different resource types differ in specialization and resource partitioning among ants, and whether the identity of the core ant species is similar among resource types. We monitored ant interactions with extrafloral nectaries, flowers, and fruits, as well as trophobiont hemipterans feeding on plants, for one year, in seven rupestrian grassland (campo rupestre) sites in southeastern Brazil. We found a highly tangled ant-plant network in which plants offering different resource types are connected by a few central ant species. The multilayer network had low modularity and specialization, but ant specialization and niche overlap differed according to the type of resource used. Beyond detecting structural differences across networks, our study demonstrates empirically that the core of most central ant species is similar across them. We suggest that foraging strategies of ant species, such as massive recruitment, may determine specialization and resource partitioning in ant-plant interactions. As this core of ant species is involved in multiple ecosystem functions, it may drive the diversity and evolution of the entire campo rupestre community. PMID:27911919

  5. Nutrition modifies critical thermal maximum of a dominant canopy ant.

    Science.gov (United States)

    Bujan, Jelena; Kaspari, Michael

    2017-10-01

    While adaptive responses to climate gradients are increasingly documented, little is known about how individuals alter their upper thermal tolerances. Long-term increases in dietary carbohydrates can elevate upper thermal tolerances in insects. We explored how the nutritional state of a Neotropical canopy ant governs its CTmax - the temperature at which individuals lose muscle control. We predicted that Azteca chartifex workers recently fed a carbohydrate-rich diet, such as honeydew and extrafloral nectar, would use that energy to increase their CTmax. Moreover, if a carbohydrate-rich diet increases CTmax, then we predicted that ants from colonies with high CTmaxs feed at a lower trophic level, and thus have a higher carbon:nitrogen ratio. We used A. chartifex colonies from a long-term fertilization experiment where phosphorus addition increased A. chartifex foraging activity with respect to controls. As foraging activity can be governed by resource availability, we first measured CTmax of field collected colonies. In freshly collected field colonies, CTmax was 2°C higher in control plots. This difference disappeared when ants were provided with only water for 10h. Ants were then provided with a 10% sucrose solution ad lib which increased CTmax by 5°C. We thus support the hypothesis that enhanced carbohydrate nutrition enables higher thermal tolerance, but this does not appear to be linked to colony trophic status, higher carbon:nitrogen ratios, or higher total body phosphorus. This short-term thermal plasticity linked to carbohydrate nutrition demonstrates the importance of ant diet in shaping their physiological traits. It is especially relevant to ant species that maintain high abundance by feeding on plant exudates. In a rapidly warming world, carbohydrate availability and use may represent a new element for predicting population and community responses of herbivorous insects. Copyright © 2017. Published by Elsevier Ltd.

  6. Plant defence as a complex and changing phenotype throughout ontogeny

    Science.gov (United States)

    Ochoa-López, Sofía; Villamil, Nora; Zedillo-Avelleyra, Paulina; Boege, Karina

    2015-01-01

    Background and Aims Ontogenetic changes in anti-herbivore defences are common and result from variation in resource availability and herbivore damage throughout plant development. However, little is known about the simultaneous changes of multiple defences across the entire development of plants, and how such changes affect plant damage in the field. The aim of this study was to assess if changes in the major types of plant resistance and tolerance can explain natural herbivore damage throughout plant ontogeny. Methods An assessment was made of how six defensive traits, including physical, chemical and biotic resistance, simultaneously change across the major transitions of plant development, from seedlings to reproductive stages of Turnera velutina growing in the greenhouse. In addition, an experiment was performed to assess how plant tolerance to artificial damage to leaves changed throughout ontogeny. Finally, leaf damage by herbivores was evaluated in a natural population. Key Results The observed ontogenetic trajectories of all defences were significantly different, sometimes showing opposite directions of change. Whereas trichome density, leaf toughness, extrafloral nectary abundance and nectar production increased, hydrogen cyanide and compensatory responses decreased throughout plant development, from seedlings to reproductive plants. Only water content was higher at the intermediate juvenile ontogenetic stages. Surveys in a natural population over 3 years showed that herbivores consumed more tissue from juvenile plants than from younger seedlings or older reproductive plants. This is consistent with the fact that juvenile plants were the least defended stage. Conclusions The results suggest that defensive trajectories are a mixed result of predictions by the Optimal Defence Theory and the Growth–Differentiation Balance Hypothesis. The study emphasizes the importance of incorporating multiple defences and plant ontogeny into further studies for a more

  7. Floral visitation by the Argentine ant reduces pollinator visitation and seed set in the coast barrel cactus, Ferocactus viridescens.

    Science.gov (United States)

    LeVan, Katherine E; Hung, Keng-Lou James; McCann, Kyle R; Ludka, John T; Holway, David A

    2014-01-01

    Mounting evidence indicates that trade-offs between plant defense and reproduction arise not only from resource allocation but also from interactions among mutualists. Indirect costs of plant defense by ants, for example, can outweigh benefits if ants deter pollinators. Plants can dissuade ants from occupying flowers, but such arrangements may break down when novel ant partners infiltrate mutualisms. Here, we examine how floral visitation by ants affects pollination services when the invasive Argentine ant (Linepithema humile) replaces a native ant species in a food-for-protection mutualism with the coast barrel cactus (Ferocactus viridescens), which, like certain other barrel cacti, produces extrafloral nectar. We compared the effects of floral visitation by the Argentine ant with those of the most prevalent native ant species (Crematogaster californica). Compared to C. californica, the Argentine ant was present in higher numbers in flowers. Cactus bees (Diadasia spp.), the key pollinators in this system, spent less time in flowers when cacti were occupied by the Argentine ant compared to when cacti were occupied by C. californica. Presumably as a consequence of decreased duration of floral visits by Diadasia, cacti occupied by L. humile set fewer seeds per fruit and produced fewer seeds overall compared to cacti occupied by C. californica. These data illustrate the importance of mutualist identity in cases where plants balance multiple mutualisms. Moreover, as habitats become increasingly infiltrated by introduced species, the loss of native mutualists and their replacement by non-native species may alter the shape of trade-offs between plant defense and reproduction.

  8. Current knowledge and future research perspectives on cassava (Manihot esculenta Crantz) chemical defenses: An agroecological view.

    Science.gov (United States)

    Pinto-Zevallos, Delia M; Pareja, Martín; Ambrogi, Bianca G

    2016-10-01

    Cassava (Manihot esculenta Crantz) is one of the most important staple crops worldwide. It constitutes the major source of carbohydrates for millions of low-income people living in rural areas, as well as a cash crop for smallholders in tropical and sub-tropical regions. The Food and Agriculture Organization of the United Nations predicts that cassava plantations will increase and production systems will intensify in the future, highlighting the need for developing strategies that improve the sustainability of production. Plant chemical defenses hold the potential for developing pest management strategies, as these plant traits can influence the behavior and performance of both pests and beneficial arthropods. Cassava plants are well-defended and produce a number of compounds involved in direct defense, such as cyanogenic glycosides, flavonoid glycosides, and hydroxycoumarins. In addition, volatile organic compounds induced upon herbivory and the secretion of extrafloral nectar act as indirect defense against herbivores by recruiting natural enemies. Here, cassava chemical defenses against pest arthropods are reviewed, with the aim of identifying gaps in our knowledge and areas of research that deserve further investigation for developing sound pest control strategies to improve sustainable production of this crop, and how these defenses can be used to benefit other crops. Cyanogenic content in cassava is also highly toxic to humans, and can cause irreversible health problems even at sub-lethal doses when consumed over prolonged periods. Therefore, the promotion of chemical defense in this crop should not aggravate these problems, and must be accompanied with the education on processing methods that reduce human exposure to cyanide.

  9. Eco-Friendly Nets and Floating Row Covers Reduce Pest Infestation and Improve Tomato (Solanum lycopersicum L. Yields for Smallholder Farmers in Kenya

    Directory of Open Access Journals (Sweden)

    Elisha O. Gogo

    2014-01-01

    Full Text Available Tomato (Solanum lycopersicum L. is an important vegetable for supplying vitamins, minerals and fiber in human diets worldwide. Successful open field production of tomato in the tropics is limited by insect pests among other constraints. Two trials were conducted at the Horticulture Research and Teaching Field, Egerton University, Kenya with the objective of evaluating the effects of agricultural nets (agronets herein called eco-friendly nets (EFNs and floating row covers (FRCs on pest population and yield of tomatoes. A randomized complete block design with five replications was used. Tomato plants were protected with either fine mesh EFN (0.4-mm pore diameter, large mesh EFN (0.9-mm pore diameter or FRC. The EFN and FRC were maintained permanently closed or opened thrice a week from 9 am to 3 pm. Two control treatments were used: open unsprayed (untreated control or open and sprayed with alpha-cypermethrin based insecticide (treated control. The use of EFN and FRC helped to manage pests with the lowest pest population obtained under FRC maintained permanently covered and the highest population recorded in the untreated control. Covering tomato plants with EFN or FRC also resulted in more marketable fruit and lower yield losses compared with the unprotected systems. The EFN and FRC offer great potential as part of integrated systems for pest management and yield improvement in tomato production in regions with a tropical climate.

  10. PA01.62. Mukta-sukti bhasma; nectar for acid peptic disorders, w.s.r to its anti-ulcer activity - an experimental study

    OpenAIRE

    Sreejith, R; ,

    2012-01-01

    Purpose: Mukta Shukti (Pearl oyster shell); a sudha varga dravya, attains better therapeutic properties with proper sodhana and marana processes. It is indicated in Amlapitta, Parinamashoola and Annadravashoola. Acharya Susruta mentioned; Amla is the property of Vidagdha Pitta. The term Amlapitta may be correlated with Acid reflux syndrome which comprises of various types of Gastro esophageal reflux diseases like Gastritis, Peptic ulcer etc. A peptic ulcer is a sore on the lining of the stoma...

  11. Espécies nectaríferas e poliníferas utilizadas pela abelha Melipona compressipes fasciculata (MELIPONINAE, APIDAE), no Maranhão

    OpenAIRE

    Kerr, Warwick Estevam; Absy, Maria Lúcia; Souza,Antônio Carlos Marques

    1986-01-01

    Este trabalho apresenta 79 espécies de plantas que fornecem néctar e/ou pólen para operárias de Melipona compressipes fasciculata, que é a abelha mais comum do Maranhão. A maioria dessas plantas são também visitadas por Apis mellifera. Sugere-se, com isso, o plantio de algumas espécies em estradas, cercas, ruas, avenidas e praças, a fim de melhorar a pasto apícola.

  12. Milkweed (Gentianales: Apocynaceae): A farmscape resource for increasing parasitism of stink bugs (Hemiptera: Pentatomidae) and providing nectar to insect pollinators and monarch butterflies

    Science.gov (United States)

    In peanut-cotton farmscapes in Georgia, stink bugs, i.e., Nezara viridula (L.), Euschistus servus (Say), and Chinavia hilaris (Say), develop in peanut and then disperse at the crop-to-crop interface to feed on fruit in cotton. The main objective of this study was to examine the influence of a habit...

  13. Selection of nectar plants for use in ecological engineering to promote biological control of rice pests by the predatory bug, Cyrtorhinus lividipennis, (Heteroptera: Miridae).

    Science.gov (United States)

    Zhu, Pingyang; Lu, Zhongxian; Heong, Kongluen; Chen, Guihua; Zheng, Xusong; Xu, Hongxing; Yang, Yajun; Nicol, Helen I; Gurr, Geoff M

    2014-01-01

    Ecological engineering for pest management involves the identification of optimal forms of botanical diversity to incorporate into a farming system to suppress pests, by promoting their natural enemies. Whilst this approach has been extensively researched in many temperate crop systems, much less has been done for rice. This paper reports the influence of various plant species on the performance of a key natural enemy of rice planthopper pests, the predatory mirid bug, Cyrtorhinus lividipennis. Survival of adult males and females was increased by the presence of flowering Tagetes erecta, Trida procumbens, Emilia sonchifolia (Compositae), and Sesamum indicum (Pedaliaceae) compared with water or nil controls. All flower treatments resulted in increased consumption of brown plant hopper, Nilaparvata lugens, and for female C. lividipennis, S. indicum was the most favorable. A separate study with a wider range of plant species and varying densities of prey eggs showed that S. indicum most strongly promoted predation by C. lividipennis. Reflecting this, S. indicum gave a relatively high rate of prey search and low prey handling time. On this basis, S. indicum was selected for more detailed studies to check if its potential incorporation into the farming system would not inadvertently benefit Cnaphalocrocis medinalis and Marasmia patnalis, serious Lepidoptera pests of rice. Adult longevity and fecundity of both pests was comparable for S. indicum and water treatments and significantly lower than the honey solution treatment. Findings indicate that S. indicumis well suited for use as an ecological engineering plant in the margins of rice crops. Sesame indicum can be a valuable crop as well as providing benefits to C. lividipennis whilst denying benefit to key pests.

  14. New approach for determination of an optimum honeybee colony's carrying capacity based on productivity and nectar secretion potential of bee forage species.

    Science.gov (United States)

    Al-Ghamdi, Ahmed; Adgaba, Nuru; Getachew, Awraris; Tadesse, Yilma

    2016-01-01

    The present study was carried out to determine an optimum honeybee colony's carrying capacity of selected valleys dominated by Ziziphus spina-christi and Acacia tortilis in the Al-Baha region, Kingdom of Saudi Arabia. The study was conducted based on the assessment of the number of colonies kept, their productivities and the existing productive bee forage resources in the target valleys with its economic implication. In the existing beekeeping practice, the average number of managed honeybee colonies introduced per square kilometer was 530 and 317 during the flowering period of Z. spina-christi and A. tortilis, respectively. Furthermore, the overall ratios of productive bee forage plants to the number of honeybee colonies introduced were 0.55 and 11.12 to Ziziphus trees and A. tortilis shrubs respectively. In the existing situation the average honey production potential of 5.21 and 0.34 kg was recorded per Ziziphus and A. tortilis plants per flowering season, respectively. The present study, revealed that the number of honeybee colonies introduced in relation to the existing bee forage potential was extremely overcrowding which is beyond the carrying capacity of bee forage resources in selected valleys and it has been observed to affect the productivities and subsequent profitability of beekeeping. The study infers that, by keeping the optimum honeybee colony's carrying capacity of valleys (88 traditional hives/km(2) or 54 Langstroth hives/km(2) in Ziziphus field and 72 traditional hives/km(2) or 44 Langstroth hives/km(2) in A. tortilis field), profitability of beekeeping can be boosted up to 130.39% and 207.98% during Z. spina-christi and A. tortilis, flowering seasons, respectively.

  15. The Factor of Influenc Brassica napa L. Secreting Nectar%影响甘蓝型油菜泌蜜的因素

    Institute of Scientific and Technical Information of China (English)

    王承赋

    2007-01-01

    分析了影响甘蓝型油菜泌蜜的因素为以下几个方面:栽培管理措施、土壤条件、病虫危害、气温、天气状况等,并介绍了油菜泌蜜涌应具备的长势长相,旨在对养蜂者确定放蜂目的地进行田间考察时提供参考.

  16. 东北林区夏季辅助蜜源植物猕猴桃%The summer assistance nectar plant kiwi fruit in the northeast of China

    Institute of Scientific and Technical Information of China (English)

    姜德成

    2010-01-01

    @@ 猕猴桃在东北林区分布较广,海拔200~1500m的林区均有生长,是夏季蜂群繁殖的好蜜源.如果流蜜期天气情况良好,强群可取到少量商品蜜,是椴树流蜜期前的最后一个辅助蜜源.

  17. 合江县的荔枝蜜源及其泌蜜规律%The nectar resource of litchi and its law of secreted honey

    Institute of Scientific and Technical Information of China (English)

    刘启霖; 温健

    2003-01-01

    四川省合江县独特的地理环境和气候,适宜荔枝生长,是我国荔枝栽培区的北沿产区,栽培荔枝历史悠久,品种繁多,病虫害少,开花泌蜜期受恶劣气候影响的年份少,是理想的放蜂采蜜场地.

  18. Discusses on the utilization of Wild Nectar Source Plant Resources with the Law%依法利用蜜源植物资源的探讨

    Institute of Scientific and Technical Information of China (English)

    张石胜; 张少斌

    2010-01-01

    蜜蜂与蜜源植物体现了共生关系.应组织各蜂场合理利用蜜粉源,以利于蜜源植物授粉.经营、种植蜜粉源植物的蜜粉资源所有权归属国家,养蜂利用蜜粉资源受保护,人人保护蜜蜂和蜜粉源植物,就是保护生态环境及人类自身.

  19. Introduction of the Homogenization Methods and the Relative Equipments of Milk and Fruit Nectars%牛奶及果汁的均质及相关设备

    Institute of Scientific and Technical Information of China (English)

    唐静静; 刘乘; 董海祥

    2003-01-01

    用于新鲜牛奶以及果实饮料的均质处理技术可归纳为高剪切均质、高压均质及超声波均质,本文分别介绍了这三种均质技术的原理及其相关的设备,并对这三种均质技术的均质效果及设备进行比较.

  20. Pollination of Specklinia by nectar-feeding Drosophila: the first reported case of a deceptive syndrome employing aggregation pheromones in Orchidaceae

    NARCIS (Netherlands)

    Karremans, A.P.; Pupulin, F.; Grimaldi, D.; Beentjes, K.K.; Butot, R.; Fazzi, G.E.; Kaspers, K.; Kruizinga, J.; Roessingh, P.; Smets, E.F.; Gravendeel, B.

    2015-01-01

    Background and Aims: The first documented observation of pollination in Pleurothallidinae was that of Endrés, who noticed that the ‘viscid sepals’ of Specklinia endotrachys were visited by a ‘small fly’. Chase would later identify the visiting flies as being members of the genus Drosophila. This

  1. Ant-plant interaction in a tropical savanna: may the network structure vary over time and influence on the outcomes of associations?

    National Research Council Canada - National Science Library

    Lange, Denise; Del-Claro, Kleber

    2014-01-01

    .... We evaluate the dynamic of an interaction network between ants and plants with extrafloral nectaries, by verifying the temporal variation in structure and outcomes of mutualism for the plant community (leaf herbivory...

  2. Ant-Plant Interaction in a Tropical Savanna: May the Network Structure Vary over Time and Influence on the Outcomes of Associations?: e105574

    National Research Council Canada - National Science Library

    Lange, Denise; Del-Claro, Kleber

    2014-01-01

    .... We evaluate the dynamic of an interaction network between ants and plants with extrafloral nectaries, by verifying the temporal variation in structure and outcomes of mutualism for the plant community (leaf herbivory...

  3. Longevity of multiple species of tephritid (Diptera) fruit fly parasitoids (Hymenoptera: Braconidae: Opiinae) provided exotic and sympatric-fruit based diets.

    Science.gov (United States)

    Stuhl, Charles; Cicero, Lizette; Sivinski, John; Teal, Peter; Lapointe, Stephen; Paranhos, Beatriz Jordão; Aluja, Martín

    2011-11-01

    While adult parasitic Hymenoptera in general feed on floral and extrafloral nectars, hemipteran-honeydews and fluids from punctured hosts, Diachasmimorpha longicaudata (Ashmead), an Old World opiine braconid introduced to tropical/subtropical America for the biological control of Anastrepha spp. (Tephritidae), can survive on fruit juices as they seep from injured fruit. An ability to exploit fruit juice would allow such a parasitoid to efficiently forage for hosts and food sources simultaneously. Two New World opiines, Doryctobracon areolatus (Szepligeti) and Utetes anastrephae (Viereck), are also prominent Anastrepha parasitoids and are roughly sympatric. All three species were provided with: (1) pulp and juice diets derived from a highly domesticated Old World fruit (orange, Citrus sinensis L.) that is only recently sympatric with the Mexican flies and parasitoids and so offered little opportunity for the evolution of feeding-adaptations and (2) a less-domesticated New World fruit (guava, Psidium guajava L.), sympatric over evolutionary time with D. areolatus and U. anastrephae. Both sexes of D. longicaudata died when provided guava pulp or juice at a rate similar to a water-only control. D. areolatus and U. anastrephae, presumably adapted to the nutrient/chemical constituents of guava, also died at a similar rate. Survival of all three species on orange pulp and juice was greater than on water, and often equaled that obtained on a honey and water solution. In confirmatory experiments in Mexico, D. areolatus and U. anastrephae, as well as other tephritid parasitoids Doryctobracon crawfordi (Viereck) and Opius hirtus (Fisher), all died at a significantly higher rates when provided guava in comparison to a honey and water diet. Such a result is likely due to guavas being repellent, innutritious or toxic. D. longicaudata clearly consumed guava juice tagged with a colored dye. Dilutions of orange and guava juice resulted in shorter lifespans than dilutions of orange

  4. Education for a New Era: Stakeholders’ Perception of Qatari Education Reform

    Directory of Open Access Journals (Sweden)

    Maha Ellili-Cherif

    2013-11-01

    Full Text Available The paper reports the results of a qualitative research study that explores principal, teacher, and parent perceptions with regard to Qatar’s education reform, Education for a New Era (EFNE launched in 2004. The study focuses on the effects of the reform on each group, their perceived advantages and disadvantages of the reform, and the challenges they face in the implementation of EFNE. Data for this study was collected through an open-ended questionnaire. The results point to the positive effects of EFNE on improving instruction, principals' leadership style, and learner attitude to education. These stakeholders believe that the reform is too ambitious and sometimes unrealistic. The three groups also report challenges that revolve around the amount of extra effort and work it requires from them, the continuous reform changes, and the threats to the local culture and language. Discussion and conclusions are provided regarding EFNE.

  5. Tunable diameter electrostatically formed nanowire for high sensitivity gas sensing

    Institute of Scientific and Technical Information of China (English)

    Alex Henning; Nandhini Swaminathan; Andrey Godkin; Gil Shalev; Iddo Amit; Yossi Rosenwaks

    2015-01-01

    We report on an electrostatically formed nanowire (EFN)-based sensor with tunable diameters in the range of 16 nm to 46 nm and demonstrate an EFN- based field-effect transistor as a highly sensitive and robust room temperature gas sensor. The device was carefully designed and fabricated using standard integrated processing to achieve the 16 nm EFN that can be used for sensing without any need for surface modification. The effective diameter for the EFN was determined using Kelvin probe force microscopy accompanied by three- dimensional electrostatic simulations. We show that the EFN transistor is capable of detecting 100 parts per million of ethanol gas with bare SiO2.

  6. Ultrasonographic findings of epipericardial fat necrosis: A case report

    Energy Technology Data Exchange (ETDEWEB)

    Park, Chan Yeong; Hwang, Hye Jeon; Lee, Kwan Seop; Lee, In Jae; Park, Kyoung Ha [Dept. of Internal Medicine, Hallym University College of Medicine, Hallym University Sacred Heart Hospital, Anyang (Korea, Republic of)

    2016-04-15

    Epipericardial fat necrosis (EFN) is an infrequent cause of acute chest pain. In rare cases like these, conservative treatment is necessary. Clinically, EFN may mimic emergent cardiopulmonary conditions, such as acute myocardial infarction. Computed tomography (CT) and magnetic resonance imaging characteristics of EFN is well described as encapsulated fatty lesion with perilesional soft tissue strands and thickening of adjacent pericardium in the epipericardial area. For confirmation of the diagnosis, involution of this lesion on follow-up is important. We present a case of EFN observed with ultrasonography (USG). This lesion was shown as a well-defined ovoid shaped mass with heterogeneous echogenicity in the left side of cardiophrenic space on USG. There was no color flow on Doppler USG. Follow-up USG and CT revealed decrease in the size of the lesion.

  7. ClEST cluster :Cl_singleton1497 [ClEST

    Lifescience Database Archive (English)

    Full Text Available AGCTTATGCACCACCAAATTTTACAAGTTAAAAAAAAATTATTATAG fw13053 1 CKLF-like MARVEL transmembrane domain-containing protein 4 [Camponotus floridanus] EFN61419 1.7402E-34 GO:0016021 GO:0016020 ...

  8. Ephrin-B-dependent thymic epithelial cell-thymocyte interactions are necessary for correct T cell differentiation and thymus histology organization: relevance for thymic cortex development.

    Science.gov (United States)

    Cejalvo, Teresa; Munoz, Juan J; Tobajas, Esther; Fanlo, Lucía; Alfaro, David; García-Ceca, Javier; Zapata, Agustín

    2013-03-15

    Previous analysis on the thymus of erythropoietin-producing hepatocyte kinases (Eph) B knockout mice and chimeras revealed that Eph-Eph receptor-interacting proteins (ephrins) are expressed both on T cells and thymic epithelial cells (TECs) and play a role in defining the thymus microenvironments. In the current study, we have used the Cre-LoxP system to selectively delete ephrin-B1 and/or ephrin-B2 in either thymocytes (EfnB1(thy/thy), EfnB2(thy/thy), and EfnB1(thy/thy)EfnB2(thy/thy) mice) or TECs (EfnB1(tec/tec), EfnB2(tec/tec), and EfnB1(tec/tec)EfnB2(tec/tec) mice) and determine the relevance of these Eph ligands in T cell differentiation and thymus histology. Our results indicate that ephrin-B1 and ephrin-B2 expressed on thymocytes play an autonomous role in T cell development and, expressed on TECs, their nonautonomous roles are partially overlapping. The effects of the lack of ephrin-B1 and/or ephrin-B2 on either thymocytes or TECs are more severe and specific on thymic epithelium, contribute to the cell intermingling necessary for thymus organization, and affect cortical TEC subpopulation phenotype and location. Moreover, ephrin-B1 and ephrin-B2 seem to be involved in the temporal appearance of distinct cortical TECs subsets defined by different Ly51 levels of expression on the ontogeny.

  9. Effect of nectar pillaging by native stingless bees (Hymenoptera: Apidae in the abscission of flowers of Bougainvillea spectabilis Willd. (Nyctaginaceae - doi: 10.4025/actascibiolsci.v33i4.8191 Effect of nectar pillaging by native stingless bees (Hymenoptera: Apidae in the abscission of flowers of Bougainvillea spectabilis Willd. (Nyctaginaceae - doi: 10.4025/actascibiolsci.v33i4.8191

    Directory of Open Access Journals (Sweden)

    Igor Inforzato

    2011-09-01

    Full Text Available This study had as objective to evaluate whether the pillaging activity by native bees influences floral abscission. Samples were collected in ten individuals of Bougainvillea spectabilis. In the period between May 4 and June 1st, 2009, 2,874 flowers were collected on the ground and 2,895 from the plants, with three-day intervals between each collection and a total of 10 repetitions in each plant. We measured the total of closed flowers, open flowers, robbed flowers, normal flowers, open robbed flowers and non-robber open flowers, in both soil and plant. For the statistical analysis, the T-test was used to see whether there was a difference between the averages obtained from the evaluated characteristics between the soil flowers and plant flowers. Simple linear regression was used to see whether there was a relationship between the closed flowers and robbed closed flowers found on the ground and open flowers and non-robbed open flowers in the plant. There were significant differences regarding all variables measured between soil and plant. A correlation was found at both closed flowers and robbed closed flowers found on the ground and open flowers and non-robbed open flowers in the plant.This study had as objective to evaluate whether the pillaging activity by native bees influences floral abscission. Samples were collected in ten individuals of Bougainvillea spectabilis. In the period between May 4 and June 1st, 2009, 2,874 flowers were collected on the ground and 2,895 from the plants, with three-day intervals between each collection and a total of 10 repetitions in each plant. We measured the total of closed flowers, open flowers, robbed flowers, normal flowers, open robbed flowers and non-robber open flowers, in both soil and plant. For the statistical analysis, the T-test was used to see whether there was a difference between the averages obtained from the evaluated characteristics between the soil flowers and plant flowers. Simple linear regression was used to see whether there was a relationship between the closed flowers and robbed closed flowers found on the ground and open flowers and non-robbed open flowers in the plant. There were significant differences regarding all variables measured between soil and plant. A correlation was found at both closed flowers and robbed closed flowers found on the ground and open flowers and non-robbed open flowers in the plant.

  10. Control of vegetable pests in Benin - Farmers' preferences for eco-friendly nets as an alternative to insecticides.

    Science.gov (United States)

    Vidogbéna, Faustin; Adégbidi, Anselme; Tossou, Rigobert; Assogba-Komlan, Françoise; Ngouajio, Mathieu; Martin, Thibaut; Simon, Serge; Parrot, Laurent; Zander, Kerstin K

    2015-01-01

    We investigated if eco-friendly nets (EFNs) are a viable and acceptable alternative to extremely high levels of insecticide use in vegetable production. Using a choice experiment, we found that vegetable producing farmers in Benin preferred all of the characteristics of EFNs except the higher labor requirements. The nets had been distributed in a trial phase for free but in the long run farmers would need to purchase the EFNs. The break-even point for investing in nets was found to vary with the lifespan of EFNs, their purchase price and potential health benefits from avoiding large quantities of insecticides. To break even the nets need to be used for at least two production cycles. To overcome risk-averse farmer's reluctance to adopt EFNs we propose a credit and warranty scheme along with the purchase of the nets. The study's findings can guide the implementation of EFNs in other African countries as part of integrated pest management with global benefits for the environment and human health.

  11. Eating Well with Scleroderma

    Science.gov (United States)

    ... rated cane juice, fructose, brown rice syrup, honey, agave nectar, molasses, corn syrup and maple syrup. • Consider ... corn syrup • Corn syrup solids (check ingredients) • Honey • Agave nectar • Fruit juices containing apple or pear • Berries ...

  12. The effect of conditional EFNB1 deletion in the T cell compartment on T cell development and function

    Directory of Open Access Journals (Sweden)

    Jin Wei

    2011-12-01

    Full Text Available Abstract Background Eph kinases are the largest family of cell surface receptor tyrosine kinases. The ligands of Ephs, ephrins (EFNs, are also cell surface molecules. Ephs interact with EFNs transmitting signals in both directions, i.e., from Ephs to EFNs and from EFNs to Ephs. EFNB1 is known to be able to co-stimulate T cells in vitro and to modulate thymocyte development in a model of foetal thymus organ culture. To further understand the role of EFNB1 in T cell immunity, we generated T-cell-specific EFNB1 gene knockout mice to assess T cell development and function in these mice. Results The mice were of normal size and cellularity in the thymus and spleen and had normal T cell subpopulations in these organs. The bone marrow progenitors from KO mice and WT control mice repopulated host spleen T cell pool to similar extents. The activation and proliferation of KO T cells was comparable to that of control mice. Naïve KO CD4 cells showed an ability to differentiate into Th1, Th2, Th17 and Treg cells similar to control CD4 cells. Conclusions Our results suggest that the function of EFNB1 in the T cell compartment could be compensated by other members of the EFN family, and that such redundancy safeguards the pivotal roles of EFNB1 in T cell development and function.

  13. 长白山野生蜜源植物种质资源调查报告%Investigation and Exploitation of the Wild Nectar Source Plant Resources in Changbai Mountains

    Institute of Scientific and Technical Information of China (English)

    周繇

    2002-01-01

    重点介绍了长白山蜜源植物的种类、特点、开发利用的现状、存在的问题、开发前景、应采取的措施等方面内容,为开发利用这一地区的宝贵资源提供一些原始资料。

  14. 论"五味甘露方"与藏药浴%The priscription of "Five-tasts nectar" (bdud-rtsi lnga-lums)and Tibetan herbal bath

    Institute of Scientific and Technical Information of China (English)

    吉太加

    2007-01-01

    藏药浴是藏医独特的外治方法之一,它是在温泉浴疗法的基础上,依据传统藏医药的基础理论而创造出来的."五味甘露方"是藏药浴的基本配方,现已发展成为经典组方.本文就此作一全面的介绍和分析.

  15. 蒙医伊希巴拉珠尔及《甘露四部》%Yeshes Palbyor and Gan lu si bu(The Four Tantras of Nectar)

    Institute of Scientific and Technical Information of China (English)

    苏日雅

    2004-01-01

    伊希巴拉珠尔1704年诞生于青海省海晏县,青少年时代在塔尔寺学习医药学、佛学与语言学,28岁返回故乡贡龙寺,并在此终生.一生从事临床治疗及蒙医学研究,代表著作为.在此著作中,提出"六基症"学说与寒热理论.

  16. 山楂复合果茶稳定性及生产工艺的研究%Study on the stable technology and production process of hawthorn compound nectar

    Institute of Scientific and Technical Information of China (English)

    李建昌; 田呈瑞

    2005-01-01

    研究山楂复合果茶的生产工艺及其稳定技术,试验结果表明:最佳原料配比为山楂果浆55%、胡萝卜浆5%、红枣浆15%、枸杞浆2%;最佳稳定剂为复合稳定剂CMC 005%和黄原胶001%;最佳均质条件为压力20~25MPa,均质2次.

  17. Presenilin mediates neuroprotective functions of ephrinB and brain-derived neurotrophic factor and regulates ligand-induced internalization and metabolism of EphB2 and TrkB receptors.

    Science.gov (United States)

    Barthet, Gael; Dunys, Julie; Shao, Zhiping; Xuan, Zhao; Ren, Yimin; Xu, Jindong; Arbez, Nicolas; Mauger, Gweltas; Bruban, Julien; Georgakopoulos, Anastasios; Shioi, Junichi; Robakis, Nikolaos K

    2013-02-01

    Activation of EphB receptors by ephrinB (efnB) ligands on neuronal cell surface regulates important functions, including neurite outgrowth, axonal guidance, and synaptic plasticity. Here, we show that efnB rescues primary cortical neuronal cultures from necrotic cell death induced by glutamate excitotoxicity and that this function depends on EphB receptors. Importantly, the neuroprotective function of the efnB/EphB system depends on presenilin 1 (PS1), a protein that plays crucial roles in Alzheimer's disease (AD) neurodegeneration. Furthermore, absence of one PS1 allele results in significantly decreased neuroprotection, indicating that both PS1 alleles are necessary for full expression of the neuroprotective activity of the efnB/EphB system. We also show that the ability of brain-derived neurotrophic factor (BDNF) to protect neuronal cultures from glutamate-induced cell death depends on PS1. Neuroprotective functions of both efnB and BDNF, however, were independent of γ-secretase activity. Absence of PS1 decreases cell surface expression of neuronal TrkB and EphB2 without affecting total cellular levels of the receptors. Furthermore, PS1-knockout neurons show defective ligand-dependent internalization and decreased ligand-induced degradation of TrkB and Eph receptors. Our data show that PS1 mediates the neuroprotective activities of efnB and BDNF against excitotoxicity and regulates surface expression and ligand-induced metabolism of their cognate receptors. Together, our observations indicate that PS1 promotes neuronal survival by regulating neuroprotective functions of ligand-receptor systems.

  18. The Endogenous Feedback Network

    DEFF Research Database (Denmark)

    Augustenborg, Claudia Carrara

    2010-01-01

    proposals, it will first be considered the extents of their reciprocal compatibility, tentatively shaping an integrated, theoretical profile of consciousness. A new theory, the Endogenous Feedback Network (EFN) will consequently be introduced which, beside being able to accommodate the main tenets...... of the reviewed theories, appears able to compensate for the explanatory gaps they leave behind. The EFN proposes consciousness as the phenomenon emerging from a distinct network of neural paths broadcasting the neural changes associated to any mental process. It additionally argues for the need to include a 5th...

  19. European guidelines on management of restless legs syndrome

    DEFF Research Database (Denmark)

    Garcia-Borreguero, Diego; Ferini-Strambi, Luigi; Kohnen, Ralf

    2012-01-01

    Since the publication of the first European Federation of Neurological Societies (EFNS) guidelines in 2005 on the management of restless legs syndrome (RLS; also known as Willis-Ekbom disease), there have been major therapeutic advances in the field. Furthermore, the management of RLS is now a part...... of routine neurological practice in Europe. New drugs have also become available, and further randomized controlled trials have been undertaken. These guidelines were undertaken by the EFNS in collaboration with the European Neurological Society and the European Sleep Research Society....

  20. 绿叶挥发物及其生态功能研究进展%Advances in Green Leaf Volatiles and Its Ecological Functions

    Institute of Scientific and Technical Information of China (English)

    高宇; 孙晓玲; 金珊; 张正群; 边磊; 罗宗秀; 陈宗懋

    2012-01-01

    Green leaf volatiles (GLV) play an important role in the chemical information network among plants, pest insects and natural enemies. That the release disciplines, metabolic pathways and the ecological functions on different biological communities of GLV was systematacially introduced in the paper. Defense-related genes and secondary metabolites can be induced and generated by GLV in plants defense response. GLV itself and HIPVs and extrafloral nectar induced by GLV can both be spreaded as the warning signals between plants, to attract and repel herbivorous insects, to play the role of synergistic and inhibitive effects with insect pheromones, to attract parasitic wasps and also to affect the growth of pathogenic micro-organisms. Although many natural enemies can be apparently allured by GLV in the laboratory conditions, their parasitic and predatory behaviors are easily influenced by background odors, meteorological conditions, population distribution and quantity of insect pests, and many other factors in the field conditions. It is too complicated and difficult to achieve the ideal biological control efficiency. Before indirect defensive functions of herbivore-induced plant volatiles are used as the regulatory measures with the chemical ecology for phytophagous insect populations in fields, many unknown aspects such as chemical genetics and ecology of insect pests, the interaction mechanism among plants, pest insects and natural enemies, the interactions between the control efficiency and different population densities of herbivorous insects in fields, are still needed to do in-depth research in order to determine multiple ecological functions of the key substances of HIPVs and develop application technology in fields.%系统总结了绿叶挥发物的释放规律、代谢途径和对不同生物群落的生态调控功能,包括能诱导植物生成相关防御基因和防御化合物,自身及其诱导生成的虫害诱导植物挥

  1. Node-Centric Detection of Overlapping Communities in Social Networks

    CERN Document Server

    Cohen, Yehonatan; Rubin, Amir

    2016-01-01

    We present NECTAR, a community detection algorithm that generalizes Louvain method's local search heuristic for overlapping community structures. NECTAR chooses dynamically which objective function to optimize based on the network on which it is invoked. Our experimental evaluation on both synthetic benchmark graphs and real-world networks, based on ground-truth communities, shows that NECTAR provides excellent results as compared with state of the art community detection algorithms.

  2. Canopy light environment influences apple leaf physiology and fruit quality

    OpenAIRE

    Campbell, Richard J.

    1991-01-01

    Several experiments were conducted to determine: the influence of canopy position, girdling, and defoliation on nectar production; whether instantaneous light measurements yield reliable estimates of cumulative seasonal light levels within the canopy; and the effect of the canopy light environment on spur leaf physiology and fruit quality. Defoliation of nongirdled flowering spurs had no effect on nectar production or composition, while defoliation of girdled spurs n~duced nectar sugar concen...

  3. The morphological range in Mallotus (Euphorbiaceae) and a taxonomic revision of its section Rottleropsis (including Axenfeldia) in Malesia, Thailand and Africa .

    NARCIS (Netherlands)

    Sierra, S.E.C.; Aparicio, M.; Gebraad, M.J.H.; Kulju, K.K.M.; Welzen, van P.C.

    2007-01-01

    The range of diagnostic morphological features in the whole genus Mallotus is reviewed as background to the taxonomic treatment of section Rottleropsis s.l. Special emphasis is given to the indumentum, habit, stipules, leaves, extrafloral nectaries, domatia, inflorescences, flowers, pollen and fruit

  4. Sooty Mould Disease Caused by Leptoxyphium kurandae on Kenaf.

    Science.gov (United States)

    Choi, In-Young; Kang, Chan-Ho; Lee, Geon-Hwi; Park, Ji-Hyun; Shin, Hyeon-Dong

    2015-09-01

    In September 2013, we discovered sooty mould growing on kenaf with the extrafloral nectaries in Iksan, Korea and identified the causative fungus as Leptoxyphium kurandae based on morphological characteristics and phylogenetic analyses. This is the first report of sooty mould caused by L. kurandae on kenaf in Korea and globally.

  5. Optimisation of a honeybee-colony's energetics via social learning based on queuing delays

    Science.gov (United States)

    Thenius, Ronald; Schmickl, Thomas; Crailsheim, Karl

    2008-06-01

    Natural selection shaped the foraging-related processes of honeybees in such a way that a colony can react to changing environmental conditions optimally. To investigate this complex dynamic social system, we developed a multi-agent model of the nectar flow inside and outside of a honeybee colony. In a honeybee colony, a temporal caste collects nectar in the environment. These foragers bring their harvest into the colony, where they unload their nectar loads to one or more storer bees. Our model predicts that a cohort of foragers, collecting nectar from a single nectar source, is able to detect changes in quality in other food sources they have never visited, via the nectar processing system of the colony. We identified two novel pathways of forager-to-forager communication. Foragers can gain information about changes in the nectar flow in the environment via changes in their mean waiting time for unloadings and the number of experienced multiple unloadings. This way two distinct groups of foragers that forage on different nectar sources and that never communicate directly can share information via a third cohort of worker bees. We show that this noisy and loosely knotted social network allows a colony to perform collective information processing, so that a single forager has all necessary information available to be able to 'tune' its social behaviour, like dancing or dance-following. This way the net nectar gain of the colony is increased.

  6. Coupling mechanism of interface-induced generation-recombination current with the floating source in nMOSFET

    Science.gov (United States)

    Chen, Haifeng; Xie, Duan; Guo, Lixin

    2016-11-01

    This paper presents a detailed investigation of the interface trap-induced generation-recombination current IGR in an n-type MOSFET. Under the positive drain bias VD-step-mode measurement, IGR demonstrates some abnormal changes and even transforms from the generation current to the recombination current. These phenomena ascribe to the coupling mechanism of IGR with the floating source. The core of this mechanism is that the floating source leads to the variable ΔEFN, which is the difference of the electron's quasi-Fermi levels between the source and the drain. The plus-minus sign of ΔEFN determines the function of the interface trap serving as the generation or recombination center, and the magnitude of ΔEFN determines the shape of IGR curve. Additionally, the area Ω of IGR curve is introduced to verify and quantitatively describe this coupling mechanism. It is found that Ω has the linear relationship with ΔEFN and the slope is 19 p/eV. This coupling mechanism provides a potential way to control the pA current based on the interface trap.

  7. The Electrostatically Formed Nanowire: A Novel Platform for Gas-Sensing Applications

    Directory of Open Access Journals (Sweden)

    Gil Shalev

    2017-02-01

    Full Text Available The electrostatically formed nanowire (EFN gas sensor is based on a multiple-gate field-effect transistor with a conducting nanowire, which is not defined physically; rather, the nanowire is defined electrostatically post-fabrication, by using appropriate biasing of the different surrounding gates. The EFN is fabricated by using standard silicon processing technologies with relaxed design rules and, thereby, supports the realization of a low-cost and robust gas sensor, suitable for mass production. Although the smallest lithographic definition is higher than half a micrometer, appropriate tuning of the biasing of the gates concludes a conducting channel with a tunable diameter, which can transform the conducting channel into a nanowire with a diameter smaller than 20 nm. The tunable size and shape of the nanowire elicits tunable sensing parameters, such as sensitivity, limit of detection, and dynamic range, such that a single EFN gas sensor can perform with high sensitivity and a broad dynamic range by merely changing the biasing configuration. The current work reviews the design of the EFN gas sensor, its fabrication considerations and process flow, means of electrical characterization, and preliminary sensing performance at room temperature, underlying the unique and advantageous tunable capability of the device.

  8. High EPHB2 mutation rate in gastric but not endometrial tumors with microsatellite instability

    NARCIS (Netherlands)

    Davalos, V.; Dopeso, H.; Velho, S.; Ferreira, A. M.; Cirnes, L.; Diaz-Chico, N.; Bilbao, C.; Ramirez, R.; Rodriguez, G.; Falcon, O.; Leon, L.; Niessen, R. C.; Keller, G.; Dallenbach-Hellweg, G.; Espin, E.; Armengol, M.; Plaja, A.; Perucho, M.; Imai, K.; Yamamoto, H.; Gebert, J. F.; Diaz-Chico, J. C.; Hofstra, R. M.; Woerner, S. M.; Seruca, R.; Schwartz, S.; Arango, D.

    2007-01-01

    The EPH/EFN family of receptor tyrosine kinases regulates cell adhesion and migration and has an important role in controlling cell positioning in the normal intestinal epithelium. Inactivation of EPHB2 has recently been shown to accelerate tumorigenesis in the colon and rectum, and we have previous

  9. Floral resource limitation severely reduces butterfly survival, condition and flight activity in simplified agricultural landscapes.

    Science.gov (United States)

    Lebeau, Julie; Wesselingh, Renate A; Van Dyck, Hans

    2016-02-01

    Agricultural intensification has a strong negative impact on farmland biodiversity (including flower-visiting insects), but understanding the mechanisms involved in this requires experimental work. We document the impact of nectar limitation on the performance of a flower-visiting insect, the meadow brown butterfly Maniola jurtina. We conducted two types of experiments: a field experiment in agricultural landscapes with grasslands of different management intensity and an experiment in outdoor flight cages in which the nectar supply was simulated. For the field experiment, we introduced an array of nectar resources in intensively managed, nectar-poor meadows and in extensively managed, flower-rich grasslands and counted flower visitors. Despite higher butterfly abundance in the extensive meadows, our introduced nectar sources were more frequently visited in intensive meadows, indicating the lack of floral resources. The 48-h confinement under nectar-poor conditions in the flight cages had a strong negative effect on body condition, flight activity and lifetime survival compared to butterflies under nectar-rich conditions. Female lifespan was reduced by 22% and male lifespan even by 43%. Agricultural landscapes that provide limited amounts of floral nectar, and no high-quality, preferred nectar sources relative to the needs of the flower-visiting species, may create ecological sinks. Regards an insect's performance, the simple presence of nectar is not necessarily functionally adequate. The effectiveness of agri-environmental schemes for flower-visiting insects (e.g. flower strips) could be improved based on ecological and evolutionary insights on the effects of specific nectar quantities and qualities.

  10. Pollen recovered from the exoskeleton of stable flies, Stomoxys calcitrans (L.) in Gainesville, Florida

    Science.gov (United States)

    Stable flies are pestiferous blood feeding flies that attack animals and humans. Besides consuming blood, these flies will also visit flowers to take nectar meals. When feeding on nectar, flies become coated with pollen which can be used to identify flowers used by the flies. Recently, flies cove...

  11. Industrial processing effects on phenolic compounds in sour cherry (Prunus cerasus L.) fruit

    NARCIS (Netherlands)

    Toydemir, G.; Capanoglu, E.; Gomez-Roldan, M.V.; Vos, de R.C.H.; Boyacioglu, D.; Hall, R.D.; Beekwilder, M.J.

    2013-01-01

    The processed juice (or nectar) of the sour cherry, Prunus cerasus L., is widely consumed in the Balkan region and Turkey. Sour cherry is known to be rich in polyphenolic compounds, such as anthocyanins and procyanidins. In this work, the effects of processing of sour cherry fruit to nectar on polyp

  12. EFECTO DE LAS GUÍAS DE NÉCTAR SOBRE LA EFICIENCIA DE POLINIZACIÓN EN ALSTROEMERIA AUREA (ALSTROEMERIACEAE

    Directory of Open Access Journals (Sweden)

    Carlos Varela

    2009-01-01

    Full Text Available We evaluated the effect that nectar guides have on the efficiency in pollination of flowers in Alstroemeria aurea (Alstroemeriaceae, a herbaceous, xenogamous plant, which blooms in temperate forests of southern South America. The flowers were manipulated in situ and subjected to three treatments: flowers with nectar guides (FCG, not manipulated, control; flowers without nectar guides (FSG, flowers with nectar guides that were obscured and control-control (CC, flowers in which the nectariferous tepals were covered by other nectariferous tepals to test the possible effect of double petals. The efficiency of pollination was evaluated as a function of visitation frequency, quantity of pollen deposited on the stigmas of visited flowers and quantity of accumulated nectar. Our results show that the absence of nectar guides significantly affected the efficiency of visits by pollinators (¿2 = 18.97, df: 2, p <<0.004 the quantity of pollen grains deposited on stigmas (F = 19.39 ; Gl: 2, p <<0.0001 and the accumulated volume of nectar (F = 12.87, df: 2, p <<0.005. The FSG were less visited, received fewer pollen grains per stigma and had a higher volume of accumulated nectar, unlike the FCG and CC. About 90% of all floral visits were accomplished by Bombus ruderathus (84.11% and B. dahlbomii (8.41 %, that possess well developed sensory perception (responding to nectar guide patterns in the flowers. We propose that the absence of nectar guides from the flowers of A. aurea, eliminated orientation patterns assisting visitors, indicating access to rewards, and consequently affected their pollination.

  13. Convergence of Wigner integrals to the tetilla law

    CERN Document Server

    Deya, Aurélien

    2011-01-01

    If x and y are two free semicircular random variables in a non-commutative probability space (A,E) and have variance one, we call the law of 2^{-1/2}(xy+yx) the tetilla law (and we denote it by T), because of the similarity between the form of its density and the shape of the tetilla cheese from Galicia. In this paper, we prove that a unit-variance sequence {F_n} of multiple Wigner integrals converges in distribution to T if and only if E[F_n^4]--> E[T^4] and E[F_n^6]--> E[T^6]. This result should be compared with limit theorems of the same flavor, recently obtained by Kemp, Nourdin, Peccati & Speicher and Nourdin & Peccati.

  14. Overlapping Leaves Covering Flowers in the Alpine Species Eriophyton wallichii (Lamiaceae): Key Driving Factors and Their Potential Impact on Pollination.

    Science.gov (United States)

    Peng, De-Li; Song, Bo; Yang, Yang; Niu, Yang; Sun, Hang

    2016-01-01

    Extrafloral structures are supposed to have evolved to protect flowers from harsh physical environments but might have effects on pollination. Overlapping leaves cover flowers in Eriophyton wallichii, an alpine perennial endemic to the Himalaya-Hengduan Mountains. In previous study, it has showed that these extrafloral leaves can protect interior flowers from temperature fluctuations caused by drastic solar radiation fluctuations, but these leaves may also protect interior flowers from rain wash and UVB damage, and we do not know which one is the main function. In this study, we investigated whether rain and UVB protection are the main functions of overlapping leaves covering flowers and their potential impact on pollination. We first measured the intensities of UVB radiation in open air, beneath leaves and corollas, and then examined pollen susceptibility to different intensities of UVB and rain in the laboratory to estimate whether corollas per se protect interior pollen from UVB and rain damage. We also carried out pollination treatments and observed pollinator visitation of flowers with and without leaves in the field to assess whether the overlapping leaves covering flowers impair pollinator attraction. Our results showed that (1) water and strong UVB significantly decreased pollen germinability, but corollas per se could protect pollen from UVB and rain damage; (2) no autonomous self-pollination and apomixis occurred, and pollinators were essential for the reproduction of E. wallichii; however, flower coverage by overlapping leaves did not limit pollination. We suggested that rain and UVB protection was not the main function of overlapping leaves covered flowers, given that this protection can be provided by corollas per se. Alternatively, this extrafloral structure in E. wallichii may have evolved in response to extreme high temperatures associated with the strong solar radiation fluctuations. This indicates that, even in alpine plants, extreme high

  15. Hummingbirds at artificial flowers made to resemble ornithophiles versus melittophiles

    Directory of Open Access Journals (Sweden)

    Wyndee A. Guzman

    2012-06-01

    Full Text Available Certain floral characteristics are associated with specific pollinators. Hummingbird-pollinated flowers are usually red, lack a landing platform, lack nectar guides, and contain a high amount of dilute sucrose-rich nectar. Here we test hypotheses concerning the reasons for these characters to the extent that they involve hummingbird responses. An array was set up of 16 artificial plants, each with five artificial flowers. (1 Flowers made to differ only in colour elicited a slight preference for red. (2 When colour was associated with nectar offerings, and birds generally learned to visit flowers that provided much more nectar but did not associatively learn differences as little as 2 µL. (3 Birds were offered 8 µL of 12% sucrose versus 2 µL of 48% hexose, and they did not prefer the dilute nectar; they showed no evidence of discerning sucrose from hexose; however, they preferred 48% over 12% sucrose when both were offered in the same quantity. (4 Birds preferred flowers that lacked landing platforms over those with landing platforms. (5 Birds were offered flowers with nectar guides, associated with differing nectar volumes, and they did not associate the higher nectar reward with either flower type. In summary, the feedback from hummingbirds reflects some of the differences between bird- and bee-adapted flowers, but nectar seemed less predictive than expected. Factors other than the behavioural proclivities of hummingbirds, such as adaptation to discourage bees, are discussed as additional causes for the differences between the syndromes. We also discuss significance testing for field experiments involving one unreplicated array.

  16. A Note on the Buchsbaum-Rim multiplicity of a parameter module

    CERN Document Server

    Hayasaka, Futoshi

    2009-01-01

    In this article we prove that the Buchsbaum-Rim multiplicity $e(F/N)$ of a parameter module $N$ in a free module $F=A^r$ is bounded above by the colength $\\ell_A(F/N)$. Moreover, we prove that once the equality $\\ell_A(F/N)=e(F/N)$ holds true for some parameter module $N$ in $F$, then the base ring $A$ is Cohen-Macaulay.

  17. EnergyFit Nevada (formerly known as the Nevada Retrofit Initiative) final report and technical evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Carvill, Anna; Bushman, Kate; Ellsworth, Amy

    2014-06-17

    The EnergyFit Nevada (EFN) Better Buildings Neighborhood Program (BBNP, and referred to in this document as the EFN program) currently encourages Nevada residents to make whole-house energy-efficient improvements by providing rebates, financing, and access to a network of qualified home improvement contractors. The BBNP funding, consisting of 34 Energy Efficiency Conservation Block Grants (EECBG) and seven State Energy Program (SEP) grants, was awarded for a three-year period to the State of Nevada in 2010 and used for initial program design and implementation. By the end of first quarter in 2014, the program had achieved upgrades in 553 homes, with an average energy reduction of 32% per home. Other achievements included: Completed 893 residential energy audits and installed upgrades in 0.05% of all Nevada single-family homes1 Achieved an overall conversation rate of 38.1%2 7,089,089 kWh of modeled energy savings3 Total annual homeowner energy savings of approximately $525,7523 Efficiency upgrades completed on 1,100,484 square feet of homes3 $139,992 granted in loans to homeowners for energy-efficiency upgrades 29,285 hours of labor and $3,864,272 worth of work conducted by Nevada auditors and contractors4 40 contractors trained in Nevada 37 contractors with Building Performance Institute (BPI) certification in Nevada 19 contractors actively participating in the EFN program in Nevada 1 Calculated using 2012 U.S. Census data reporting 1,182,870 homes in Nevada. 2 Conversion rate through March 31, 2014, for all Nevada Retrofit Initiative (NRI)-funded projects, calculated using the EFN tracking database. 3 OptiMiser energy modeling, based on current utility rates. 4 This is the sum of $3,596,561 in retrofit invoice value and $247,711 in audit invoice value.

  18. Epidemiologic variability of chronic inflammatory demyelinating polyneuropathy with different diagnostic criteria: study of a UK population.

    Science.gov (United States)

    Rajabally, Yusuf A; Simpson, Benjamin S; Beri, Sushil; Bankart, John; Gosalakkal, Jayaprakash A

    2009-04-01

    Epidemiologic data on chronic inflammatory demyelinating polyneuropathy (CIDP) is limited, and previous studies have shown variable results. The frequencies of CIDP subtypes remain unknown. Variations due to use of different diagnostic criteria have not been studied. We examined the prevalence and incidence of CIDP in Leicestershire and Rutland, UK (population 963,600). Prevalence day was 1 May 2008. The prevalence of CIDP fulfilling the 2006 clinical and electrophysiologic European Federation of Neurological Societies/Peripheral Nerve Society (EFNS/PNS) criteria was 4.77 per 100,000 (95% confidence interval [CI] 3.49-6.37). Using the 1991 American Academy of Neurology (AAN) criteria, the prevalence was 1.97 per 100,000 in this population (95% CI 1.19-3.08). Lewis-Sumner syndrome was diagnosed in 15.2% of patients, and 23.9% had pure sensory onset. Over 40% required no immunotherapy, and 84.6% of those treated responded. More than 80% of the AAN criteria-negative but EFNS/PNS criteria-positive patients were responsive to treatment. Both sets of criteria were equally likely to identify patients who required therapy. The mean annual incidence rate over the 3 years preceding the prevalence day was 0.70 per 100,000/year using EFNS/PNS criteria (95% CI 0.43-1.08), and 0.35 per 100,000/year using AAN criteria (95% CI 0.17-0.64). We conclude that the AAN criteria may underestimate prevalence and incidence of the disease. The EFNS/PNS criteria provide higher diagnostic sensitivity and are of greater clinical relevance, and they also offer a useful breakdown of the epidemiologic data for CIDP subtypes.

  19. Pharmacological treatment of neuropathic pain in older persons

    OpenAIRE

    2008-01-01

    Clair Haslam1, Turo Nurmikko21The Walton Centre for Neurology and Neurosurgery, Liverpool, England, UK; 2The Pain Research Institute, Division of Neurological Science, University of Liverpool, Liverpool, England, UKAbstract: Interest and research into the mechanisms and treatment of neuropathic pain have increased during recent years, but current treatment is still far from satisfactory (Dworkin et al 2003; Attal et al 2006). The European Federation of Neurological Societies (EFNS) Task Force...

  20. Changing the face of learning: ebrain and UCL distance learning diploma in clinical neurology.

    Science.gov (United States)

    Dassan, Pooja

    2012-12-11

    ebrain is a groundbreaking e-learning program.(1) It is an exciting and novel interactive online program in clinical neuroscience aimed at hospital trainees, consultants in neurology, and other neuroscience specialties. ebrain was developed in partnership with the Joint Neuroscience Council (JNC), University College London (UCL), the European Federation of Neurological Societies (EFNS), and the European Neurological Society (ENS). At its core is a program of 550 lectures covering the breadth of clinical neurosciences.

  1. Effect of nectar pillaging by native stingless bees (Hymenoptera: Apidae in the abscission of flowers of Bougainvillea spectabilis Willd. (Nyctaginaceae =Efeito da pilhagem de néctar por abelhas nativas sem ferrão (Hymenoptera: Apidae na abscisão floral de Bougainvillea spectabilis Willd. (Nyctaginaceae

    Directory of Open Access Journals (Sweden)

    Rodrigo Arand

    2011-09-01

    Full Text Available This study had as objective to evaluate whether the pillaging activity by native bees influences floral abscission. Samples were collected in ten individuals of Bougainvillea spectabilis. In the period between May 4 and June 1st, 2009, 2,874 flowers were collected on the ground and 2,895 from the plants, with three-day intervals between each collection and a total of 10 repetitions in each plant. We measured the total of closed flowers, open flowers, robbed flowers, normal flowers, open robbed flowers and nonrobber open flowers, in both soil and plant. For the statistical analysis, the T-test was used to see whether there was a difference between the averages obtained from the evaluated characteristics between the soil flowers and plant flowers. Simple linear regression was used to see whether there was a relationship between the closed flowers and robbed closed flowers found on the ground and open flowers and non-robbed open flowers in the plant. There were significant differences regarding all variables measured between soil and plant.A correlation was found at both closed flowers and robbed closed flowers found on the ground and open flowers and non-robbed open flowers in the plant.O presente trabalho teve como objetivo avaliar a atividade de pilhagemde abelhas nativas influenciando a abscisão floral de Bougainvillea spectabilis. As coletas foram realizadas em dez indivíduos de B. spectabilis. Foram coletadas 2.874 flores no solo e 2.895 na planta no período de 4/5/2009 a 1/6/2009 com intervalo de três dias entre cada coleta, totalizando 10 repetições em cada indivíduo. Foram mensuradas as flores fechadas, flores abertas, flores fechadas pilhadas, flores fechadas não pilhadas, flores abertas pilhadas e flores abertas não pilhadas tanto no solo como na planta. Para as análises estatísticas foi utilizado o Teste-T para verificar se houve diferença entre as médias obtidas das características avaliadas entre as flores do solo e as flores da planta, além de regressão linear simples para verificar se houve relação entre as flores fechadas e flores fechadas pilhadas; flores abertas e flores abertas pilhadas, encontradas no solo e flores fechadas e flores fechadas pilhadas; flores abertas e flores abertas pilhadas na planta. Houve diferença significativa em relação a todas as variáveis entre o solo e a planta. Foi verificada correlação tanto nas flores fechadas e florespilhadas fechadas encontradas no solo quanto nas flores abertas e flores abertas não pilhadas na planta.

  2. INFLUÊNCIA DE DIFERENTES pH DO MEIO DE AQUECIMENTO NA RESISTÊNCIA TÉRMICA DE Neosartorya fischeri ISOLADO DO PROCESSO PRODUTIVO DE NÉCTAR DE MAÇÃ INFLUENCE OF DISTINCT PH VALUES IN THE THERMAL RESISTANCE OF NEOSARTORYA FISCHERI ISOLATED FROM APPLE NECTAR PROCESSING

    Directory of Open Access Journals (Sweden)

    B. C. M. SALOMÃ?O

    2008-08-01

    Full Text Available

    A resistência térmica de ascósporos de N. fischeri, isolados do concentrado de maçã, foi verificada utilizando-se tubos TDT (Thermal Death Time selados, e suco de maçã, a diferentes pHs, como meio de aquecimento. As curvas obtidas a 80, 85 e 90°C mostraram um “ombro” inicial evidenciando comportamento de morte não logarítmica. Assim, o cálculo dos parâmetros cinéticos foi realizado através da linearização das mesmas. Os valores de “1/k” obtidos em pH 2,5 foram 81,3; 16,0 e 0,9 minutos para 80, 85 e 90°C, respectivamente; em pH 3,5 foram de 153,8; 22,0 e 1,0 minutos e em pH 4,5 foram de 312,5; 38,6 e 2,2 minutos, para as mesmas respectivas temperaturas. O valor de Z* (equivalente a Z foi 5,0°C a pH 2,5 e o mesmo valor (4,6°C foi encontrado em pH 3,5 e 4,5. Os valores de esterilização F(95°C nos pHs 2,5; 3,5 e 4,5 foram respectivamente 44,6; 36,8, e 77,0 segundos, considerando-se a redução da população inicial em 6 ciclos logarítmicos. Como o tratamento térmico comercial normalmente aplicado ao suco de maçã é de 95°C/30s, pode-se concluir que este não será suficientemente seguro para atingir a probabilidade de sobrevivência de 1 ascósporo a cada 105 embalagens, o que seria esperado.

    The heat resistance of N. fischeri ascospores isolated from apple concentrate was verified using closed TDT (Thermal Death Time tubes, and apple juice as heating medium (at different pHs. The curves at 80, 85 and 90°C showed an initial “shoulder” due to non logarithmic death behavior. Then, the kinetic parameters calculation was performed by linearization .The 1/k values obtained at pH 2.5 were 81.3, 16 and 0.9 minutes at 80, 85 and 90°C, respectively; at pH 3.5 were 153.8, 22.0 and 1.0 minutes and at pH 4.5 were 312.5, 38.6 and 2.2 minutes, for the same respective temperatures described above. The Z* value (Z equivalent was 5.0°C at pH 2.5 and the same value (4.6°C was find at pH 3.5 and 4.5. The sterilization values F(95°C at pHs 2.5, 3.5 and 4.5 were 44.6; 36.8 and 77.0 seconds, respectively. Considering that the commercial thermal treatment applied to apple concentrate is 95°C/30s, the conclusion is that such treatment will not guarantee the probability of survival of 1 ascospore in each set of 105 packs.

  3. 雌雄木蜂对活血丹盗蜜的行为差异及原因%Preliminary Study of the Causes and Pattern of Behavioural Differences Between Male and Female Carpenter Bees (Xylocopa sinensis) during Nectar Robbing in Glechoma longituba (Lamiaceae)

    Institute of Scientific and Technical Information of China (English)

    张彦文; 郭友好

    2006-01-01

    通过近三年的野外观察和实验揭示了活血丹的盗蜜者为中华木蜂.但其雌雄个体具有不同的访花特性和影响.雄蜂的体形稍小,访花频率是雌蜂的4倍,单花访问时间较雌蜂短(2.18 s/7.48 s),但在一个居群的单次访花数却是雌蜂的5倍(42.48/8.81),对被盗蜜花的损伤也较雌蜂低;在开放条件下,被雌雄木蜂访问过的花的座果率有明显差异(34.72%/73.59%).结果表明,体形大小的差异可能是活血丹的花冠管长度、硬度及单花产蜜量仅能适应雄蜂的盗蜜,不适应雌蜂盗蜜的主要原因,对食物资源的合理利用可能导致了中华木蜂雌雄个体在对活血丹的取食行为上发生了分化,并对其花部进化施加了不同的选择压力.

  4. Avaliação sensorial e caracterização físico-química de néctar de acerola adicionado de extrato comercial de própolis
    Evaluation sensory and characterization physical chemistry of nectar acerola added of extract commercial propolis

    Directory of Open Access Journals (Sweden)

    M. V. M. NEVES

    2011-01-01

    Full Text Available

    Este trabalho teve como objetivo avaliar os atributos sensoriais assim como determinar as características físico-químicas e cromáticas de néctares de acerola adicionados de diferentes concentrações de extrato comercial de própolis, os quais foram elaborados na proporção de 1:4 (polpa: água potável contendo 12,5% de sacarose. Os néctares foram avaliados quanto aos atributos sabor, cor, aroma e aspecto global por um painel de quarenta julgadores não treinados utilizando uma escala hedônica com questionamentos quanto à intenção de compra; foram também avaliados quanto ao teor de ácido ascórbico, sólidos solúveis totais, pH e às características cromáticas (sistema CIELAB. Com relação ao atributo “sabor”, os julgadores “gostaram” do néctar contendo 0,5% de própolis e “nem gostaram ou desgostaram” do néctar com 0,75 e 1,0%. Com relação à intenção de compra, os julgadores “comprariam” o néctar nas concentrações de 0,5%; 0,75% e 1,0%. Os resultados das características físico-químicas dos néctares nas concentrações de 0,5%; 0,75% e 1,0% revelaram que o teor de ácido ascórbico variou de 207,4 a 230,8 mg/100mL, sólidos solúveis totais de 12,4 a 12,8 ºBrix, o pH de 3,4 a 3,6 e os parâmetros de cor, no sistema CIELAB, foram (L de 50,11 a 45,00, (a de 3,64 a 3,35 e (b de 21,14 a 18,20, respectivamente. A partir dos resultados obtidos pode-se concluir que a adição de diferentes concentrações de própolis interferiu nos atributos sensoriais e nos parâmetros cromáticos do néctar de acerola, mas, no entanto, não alterou suas características físico-químicas. O néctar contendo 0,5% de própolis foi o único aceito em relação ao sabor, aroma, cor, aspecto global e intenção de compra.

  5. Nutritional significance of a winter-flowering succulent for opportunistic avian nectarivores

    CSIR Research Space (South Africa)

    Symes, CT

    2010-01-01

    Full Text Available Pycnonotus nigricans and Cape White-eyes Zosterops capensis. In both these species, the d13C of breath samples was significantly enriched compared with blood and feathers, and closely resembled that of the nectar, revealing combustion of ingested nectar... CO2 (Carleton et al. 2004, 2006, Voigt et al. 2008a, 2008b). Because of the potential for such isotopic routing in birds feeding on A. marlothii nectar, we investigated tissues with differing turnover rates, namely feathers, blood and breath...

  6. On-Orbit Engineering and Vehicle Integration Poster Presentation

    Science.gov (United States)

    Heimerdinger, Madison

    2014-01-01

    One of the duties of the MER Managers is getting the consoles to review and sign Electronic Flight Notes (EFN) and Mission Action Requests (Chit) before they are due. Chits and EFNs and are accessible through the Mission Control Center - Houston (MCC-H) Gateway. Chits are the official means of documenting questions and answers, technical direction, real-time changes to Flight Rules (FR) and procedures, request for analysis, etc. between various consoles concerning on-orbit operations. EFNs are documents used by the Flight Control Team (FCT) to communicate precise details between console positions and manage real time changes to FR and Systems Operation Data File (SODF) procedures. On GMT 2013/345 the External Active Thermal Control System (EATCS) on the Columbus (COL) Moderate Temperature Loop (MTL) Interface Heat Exchanger (IFHX) shut down due to low temperatures. Over the next couple of days, the core temperature of COL MT IFHX dropped due to the failure of the Flow Control Valve (FCV). After th