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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Bases comportementales et génétiques des apprentissages aversif et appétitif chez l'abeille, Apis mellifera / Behavioral and genetic basis of appetitive and aversive learning in the honey bee, Apis mellifera

Junca, Pierre 30 September 2015 (has links)
Dans un monde dynamique la survie des animaux dépend de leur capacité à intégrer des signaux environnementaux afin d'adapter leur comportement à la survenue de conséquences positives (nourriture) ou négatives (dangers) c'est-à-dire de leurs capacités d’apprentissages associatifs appétitif et aversif. Pendant ce travail de thèse, nous nous sommes intéressés aux bases comportementales, moléculaires et génétiques de l'apprentissage aversif et aux relations existant entre apprentissages aversif et appétitif au sein d'un groupe social. L'abeille est un insecte eusocial qui constitue un modèle de choix pour cette étude grâce à l'existence des protocoles de conditionnement appétitif de la réponse d'extension du proboscis (REP) et de conditionnement aversif de la réponse d'extension du dard (RED). Jusqu'à présent, le renforcement utilisé dans le conditionnement aversif de la RED était un choc électrique. Ce stimulus traversant la majeure partie du corps de l'abeille, il est peu aisé d'étudier les structures responsables de sa détection. Dans un premier chapitre, nous avons donc testé l’effet d’une forte température (65°C) sur la RED. Nous montrons qu’une stimulation thermique au niveau des pièces buccales, des pattes ou des antennes induit une RED. De plus, les abeilles parviennent à associer une odeur à la présentation concomitante d'une forte température. Dans un deuxième chapitre, nous avons cartographié la sensibilité thermique du corps des abeilles en mesurant la RED. Ce travail a montré que la stimulation de presque toutes les parties du corps induit une RED. De plus, ces stimulations peuvent jouer le rôle de renforcement aversif lors d’un conditionnement olfactif de la RED. Nous nous sommes ensuite intéressés aux récepteurs périphériques potentiellement impliqués dans la détection des fortes températures, et en particulier à HsTRPA (Hymenoptera specific Transient Receptor Potential A). Nous montrons que l’injection d'inhibiteurs exogènes de HsTRPA réduit les RED à la température. Ces résultats suggèrent l’implication possible d’HsTRPA dans la détection de la température chez l’abeille. Dans un troisième chapitre, nous nous sommes intéressés aux relations existant entre les capacités d’apprentissages aversif et appétitif des abeilles. En nous appuyant sur le protocole aversif thermique, combiné au protocole de conditionnement de la REP existant, nous avons étudié la distribution des capacités hédoniques appétitive et aversive au sein d'une ruche. La reine étant fécondée par 15-20 mâles, la ruche est segmentée génétiquement en autant de lignées paternelles différentes. Nos données montrent que la sensibilité des individus aux renforcements aversif (chaleur) et appétitif (sucre) détermine leurs performances d'apprentissage au sein de chaque modalité hédonique. Nous montrons de plus l’existence d’un trade-off, sous déterminisme génotypique, entre les capacités cognitives appétitive et aversive au sein de la colonie. Le quatrième chapitre a étudié la plasticité comportementale induite par les deux types de conditionnement. La REP et la RED étant des réponses de type "tout ou rien", nous nous sommes demandé si les mouvements antennaires des abeilles pouvaient procurer une mesure fine et intégrer des apprentissages appétitif et aversif. Nous avons développé un système de capture vidéo enregistrant les mouvements antennaires à haute vitesse. Nous montrons que les abeilles modifient leur réponse antennaire à une odeur après un apprentissage appétitif mais pas après un apprentissage aversif. Durant ce travail de thèse, nous avons ainsi développé deux nouveaux protocoles comportementaux en contention, et avons procuré de nouvelles données sur l’apprentissage aversif chez l’abeille. Nous avons observé un trade-off au sein de la ruche entre les capacités hédoniques appétitive et aversive, sous déterminisme génétique. De telles spécialisations cognitives pourraient jouer un rôle prépondérant dans l'évolution des groupes sociaux. / In a dynamic world, animals constantly face environmental changes that may affect them (Alock, 1997). Their survival depends on their ability to integrate this information in order to adapt their behaviors to subsequent positive or negative outcomes, in other words to their appetitive and aversive learning abilities. This thesis investigates the behavioral, molecular and genetic basis of aversive learning and its putative relationship with appetitive learning in a social group. The honeybee is a social insect which constitutes a profitable model for this study thanks to appetitive conditioning of the proboscis extension response (PER) and aversive conditioning of the sting extension response (SER) protocols that have been developed. To date, aversive conditioning of the SER has involved the use of electric shocks as a negative reinforcement. However, this stimulus is ecologically irrelevant for honeybees and electric currents pass through almost every part of the bee’s body making it difficult to study the dedicated structures and sensory pathways responsible for its detection. In the first chapter, we assessed the impact of high temperatures on SER, a stimulus that is also highly aversive. We showed that a SER may be triggered by heat stimulation of mouthparts, forelegs and antennae. In addition, we demonstrated that honeybees are able to associate an odor with high temperatures, resulting in the odor alone triggering the SER after conditioning. In the second chapter, we mapped the heat sensitivity of the bee’s body recording SER subsequent to heat stimulation. This work revealed that heat stimulation of almost every body structures (beside the wings and the tip of the abdomen) induces a SER. Furthermore, these stimulations may act as aversive reinforcement during an olfactory conditioning of the SER. We then focused on putative peripheral receptors involved in high temperature detection, specifically focusing on HsTRPA (Hymenoptra specific Transient Receptor Potential). Using a neuropharmalogical approach, we showed that HsTRPA exogenous inhibitor injections decrease SER triggered by high temperatures yet have no impact on sucrose PER. These results suggest a putative involvement of HsTRPA in the detection of high temperatures in honeybees. In the third chapter, we investigated the relationship between appetitive and aversive learning. By combining thermal aversive conditioning with the PER conditioning protocol, we studied the distribution of hedonic learning abilities in the hive. Since the queen mates with 15-20 males, the hive is, thus, genetically segmented in as many different patrilines. Our data shows that individual sensitivity to aversive (heat) and appetitive reinforcement varies among workers and determines their learning success in each hedonic modality. In addition, we observed that the better an individual (and therefore a patriline) is at appetitive learning, the less successful it will be in aversive learning, and vice versa. The forth chapter focused on the behavioral plasticity induced by the two types of conditioning. PER and SER are binary responses in an “all or nothing” fashion and subtle behavioral variations are difficult to observe. We therefore investigated if honeybee antennal movements may yield a finer measurement to integrate appetitive and aversive learning. We developed a motion capture system that records antennal movements at high speed. We showed that honeybees modify their antennal response to an odor previously associated with sucrose reward however thermal aversive conditioning did not induce any antennal movement modifications. During this PhD work, we developed two new behavioral assays in harnessed individuals, furthering our understanding on aversive learning in the honeybee. Within the hive, we observed a trade-off between appetitive and aversive hedonic learning, which was genetically influenced. Such cognitive specialization could play a key role in social evolution.
32

Etudes comportementales et neurobiologiques de l'apprentissage visuel chez l'abeille (Apis mellifera) en réalité virtuelle / Behavioral and neurobiological studies of visual learning in honey bees (Apis mellifera) in virtual reality

Buatois, Alexis 17 September 2018 (has links)
Les abeilles en libre vol montrent des capacités cognitives visuelles remarquables mais les bases neurales sous-jacentes ne peuvent pas être étudiées chez des insectes en vol. À l'inverse, le cerveau des abeilles immobilisées est accessible mais ne permet pas d'explorer l'apprentissage visuel. Pour dépasser cette limite, notre objectif a été d'établir un dispositif de réalité virtuelle pour pouvoir tester l'apprentissage visuel sur des abeilles attachées. Dans un premier temps, les abeilles ont été testées sur leur capacité à discriminer des couleurs en s'appuyant sur les renforcements positifs ou négatifs qui leur étaient associés. Ces expériences ont permis de mettre en évidence le rôle de la vision active dans la réalité virtuelle et l'importance de la phototaxie dans ce type de système. Grâce à ce dispositif, un apprentissage non élémentaire en réalité virtuelle, le patterning négatif, a été mis en place. Ainsi il a été montré que les abeilles étaient capables de résoudre cette tache en réalité virtuelle malgré sa complexité. Enfin, en s'appuyant sur le protocole de discrimination de couleurs, l'activation du cerveau a été étudiée au cours d'un test de mémoire des couleurs en analysant l'expression de gènes considérés comme des marqueurs de l'activité neurale. Les résultats de cette thèse, fournissant deux protocoles de réalité virtuelle solides pour étudier les apprentissages visuels élémentaires et non élémentaires, constituent une avancée considérable vers la possibilité de comprendre les bases neurales sous-jacentes à ces apprentissages chez l'abeille qu'ils soient simples ou complexes. / Free flying bees are known for their impressive visual cognition abilities, but the neural bases underlying those are poorly studied because of the difficulty to explore the brain in a flying insect. Conversely, it is possible to have access to the brain with tethered bees but, until now, no studies explored visual learning. To bypass this limitation, our aim was to establish a virtual reality device to test visual learning in tethered bees. First, bees were tested for their abilities to learn to discriminate colors according to the reinforcement associated to each of them. These experiments allowed to highlight the role of the active vision in virtual reality and the importance of phototaxis in this kind of device. Driven by these good results, we explored the non- elementary visual learning in bees and, more specifically, the negative patterning. The results suggest that bees were able to resolve this task in virtual reality despite its complexity. Finally, using the protocol of color discrimination, the brain activation has been explored during a color memory recall thanks to a quantification of immediate early genes considered as neural markers. This thesis provides two solid virtual reality protocols to study elementary and non-elementary visual learning in honey bees. This constitutes a huge advance and will allow to go further towards the understanding of the neural bases of simple and complex visual learning.
33

The impact of the European honey bee (Apis mellifera) on Australian native bees

Paini, Dean January 2004 (has links)
The European honey bee (Apis mellifera) has been present in Australia for approximately 150 years. For the majority of that time it was assumed this species could only be of benefit to Australia‘s natural ecosystems. More recently however, researchers and conservationists have questioned this assumption. Honey bees are an introduced species and may be affecting native fauna and flora. In particular, native bees have been highlighted as an animal that may be experiencing competition from honey bees as they are of similar sizes and both species require nectar and pollen for their progeny. Most research to date has focused on indirect measures of competition between honey bees and native bees (resource overlap, visitation rates and resource harvesting). The first chapter of this thesis reviews previous research explaining that many experiments lack significant replication and indirect measures of competition cannot evaluate the impact of honey bees on native bee fecundity or survival. Chapters two and four present descriptions of nesting biology of the two native bee species studied (Hylaeus alcyoneus and an undescribed Megachile sp.). Data collected focused on native bee fecundity and included nesting season, progeny mass, number of progeny per nest, sex ratio and parasitoids. This information provided a picture of the nesting biology of these two species and assisted in determining the design of an appropriate experiment. Chapters three and five present the results of two experiments investigating the impact of honey bees on these two species of native bees in the Northern Beekeepers Nature Reserve in Western Australia. Both experiments focused on the fecundity of these native bee species in response to honey bees and also had more replication than any other previous experiment in Australia of similar design. The first experiment (Chapter three), over two seasons, investigated the impact of commercial honey bees on Hylaeus alcyoneus, a native solitary bee. The experiment was monitored every 3-4 weeks (measurement interval). However, beekeepers did not agist hives on sites simultaneously so measurement intervals were initially treated separately using ANOVA. Results showed no impact of honey bees at any measurement interval and in some cases, poor power. Data from both seasons was combined in a Wilcoxon‘s sign test and showed that honey bees had a negative impact on the number of nests completed by H. alcyoneus. The second experiment (Chapter 5) investigated the impact of feral honey bees on an undescribed Megachile species. Hive honey bees were used to simulate feral levels of honey bees in a BACI (Before/After, Control/Impact) design experiment. There was no impact detected on any fecundity variables. The sensitivity of the experiment was calculated and in three fecundity variables (male and female progeny mass and the number of progeny per nest) the experiment was sensitive enough to detect 15-30% difference between control and impact sites. The final chapter (Chapter six) makes a number of research and management recommendations in light of the research findings.
34

Genetic variation and colony development of honey bees Apis mellifera in Kenya /

Wei, Shi. January 2001 (has links) (PDF)
Diss. (sammanfattning)--Uppsala : Sveriges lantbruksUniversity, 2001. / Härtill 4 uppsatser.
35

Avaliação de formulações alimentares no desenvolvimento de colônias de abelhas africanizadas (Apis mellifera Linnaeus, 1758) na savana amazônica de Roraima

Luis Carlos Rueda Alcárcel 29 August 2011 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / As abelhas africanizadas encontram nas flores suas principais fontes de alimento, sendo possível observar que em condições ambientais desfavoráveis há uma diminuição na população e conseqüentemente uma menor produção de mel nas épocas de florada. Em Roraima a produção de mel esta concentrada após o período de chuvas, motivo pelo qual é importante o fornecimento de uma suplementação alimentar durante as chuvas. O objetivo deste trabalho foi analisar o desenvolvimento de colônias de abelhas africanizadas A. mellifera com diferentes suplementações alimentares, para manter e/ou melhorar a produção apícola. A pesquisa foi realizada de 12 de abril a 5 de agosto de 2011 no Apiário Experimental do departamento de Zootecnia da Universidade Federal de Roraima. Foram utilizadas vinte colônias em caixas modelo Langstroth, suplementadas com alimentação energética e escolhidas aleatoriamente para receberem três diferentes rações isoprotéicas com 23% de proteína bruta. Os quatro tratamentos foram: T1 = testemunha (sem suplementação alimentar protéica); T2 = farelo de milho + farelo de soja tostada + farelo de arroz (em quantidades iguais); T3 = 30% de farelo de soja tostada + 19% de leite de soja desidratado + 20% farelo de milho + 31% açúcar cristal; T4 = 45% de farelo de soja + 40% farinha de pupunha + 15% açúcar cristal. O desempenho das dietas foi determinado pelo consumo do alimento protéico e o desenvolvimento das colônias quanto ao ganho de peso, áreas de cria e áreas de alimento, sendo que foram analisadas separadamente áreas abertas e fechadas de operárias e zangões, além de áreas com alimento (cm). O consumo de alimento e o ganho de peso foram obtidos por meio de pesagens; as áreas ocupadas nos favos foram analisadas por meio de fotografias digitais e processadas com ajuda do programa computacional Adobe Photoshop CS2. Foram encontradas diferenças significativas para o consumo de ração e o ganho de peso, sendo que, o maior consumo de ração foi observado nas colônias do tratamento 4 e o maior ganho de peso nas colônias do tratamento 1, que receberam unicamente alimentação energética e apresentaram as maiores áreas de cria e alimento. Em relação às variáveis ambientais houve correlação negativa da temperatura e umidade com o ganho de peso das colônias do tratamento 2. / Africanized bees find in the flowers their main source of food; as a result, it has been shown a reduction in population under unfavourable environmental conditions and, consequently, a lower honey production during the early spring. In Roraima, the highest honey production rates occur after the rainy season, the reason for which is important the bees be given supplement during the rainy period. This research was carried out to analyze the development of Africanized honeybee A. mellifera colonies according to different kinds of food supplements offered in order to maintain and/or increase the apicultural production rates. The research was conducted from April 12th to August 5th, 2011, in the Experimental Apiary of Zootechny Department of Federal University. It has been used twenty Langstroth beehives, provided with energetic food and chosen at random to be given three different isoproteinaceous feed containing 23% of raw protein. The four treatments were: T1 = witness (without any proteinaceous supplement); T2 = corn flour + toasted soybean flour + rice flour (in equal parts); T3 = 30% of toasted soybean flour + 19% of soybean dry milk + 20% corn flour + 31% crystal sugar; T4 = 45% of soybean flour + 40% of peach palm fruit flour+ 15% of crystal sugar. The diets performances were determined by the consumption of the proteinaceous feed; the development of the colonies, in turn, as regards weight gain, brood area and food area, being analyzed separately the uncapped and capped worker and drone areas, as well as the food area (cm). The food consumption and the weight gain were obtained by weighing; the honeycomb area was analyzed by taking digital photographs of it and processing the data using the software Adobe Photoshop CS2. It has been found significant differences for feed consumption and weight gain, showing the colonies of T4 the highest feed consumption, and the colonies of T1, which were only given energetic food, the highest weight gain; it has also been observed in the latter the biggest brood and food areas. It has occurred a negative correlation of temperature and humidity with the weight gain in one of the colonies of T2.
36

Wireless Beehive Monitoring : Using edge computing and TinyML to classify sounds

Holmgren, Mattias, Holmér, Elias January 2022 (has links)
As an essential and indispensable contributor to pollinating the world's crops and plants, the honey bee is key to the sustainability of humans' and our ecosystems' continued survival. Following in the footsteps of the companies TietoEvry and Beelabs project, this report also works towards monitoring bees during their daily activities. This project aims to investigate the feasibility of using wireless, battery-driven devices inside beehives to detect the sound of bees using machine learning for edge devices. Beelab has focused on measurements in and around the beehive regarding weight, temperature, barometric pressure and humidity. Sound analysis is still in its infancy with few finished working alternatives; therefore, this project will focus on the sound attribute by implementing machine learning and classification algorithms and applying it to a prototype—the progress is thoroughly documented in this report. The device records a snippet of sound and prepares to send it over a wireless transmission medium. By streamlining the code and optimizing the hardware, the device runs continuously for a month using a small, cheap battery.
37

Elucidating the Effects of Thiamethoxam Neonicotinoid on Honey Bee Learning Using the Proboscis Extension Response

Shepherd, David J 01 May 2017 (has links)
In this study, the effects of the neonicotinoid pesticide, thiamethoxam, are examined through the Proboscis Extension Response (PER) in honey bees (Apis mellifera). PER is a form of classical conditioning applied to honey bees through scent and reward association which quantifies learning rates. Results between groups treated with thiamethoxam did not differ significantly from untreated control groups. Potential reasons for these results are discussed. The method and experimental apparatus for testing the PER assay are also discussed.
38

Reproductive biology and nectary structure of <i>Lythrum</i> in central Saskatchewan

Caswell, Wade Devin 26 August 2008
This project examined multiple aspects of the reproductive biology of the wetland invasive species, purple loosestrife (<i>Lythrum salicaria</i> L.), in central Saskatchewan. An examination of insect taxa visiting the three floral morphs of <i>Tristylous</i> L. <i>salicaria</i>, as well as a ranking of the pollination efficiency of individual insect species, an apparent first for L salicaria, was undertaken. Surface features of the floral nectary of L. <i>salicaria</i>, as well as floral nectar secretion dynamics, were also investigated. This project also re-visited some of the previous work done on this invasive species, including various floral organ morphometrics in relation to heterostyly, and aspects of the tristylous breeding system including self-fertilization, and fertilization potential of both illegitimate pollination and legitimate pollination.<p>The trimorphic nature of the sexual floral organs of L. <i>salicaria</i> were well defined in Saskatchewan. Significant differences in length (long-, intermediate- and short-style lengths) exist between all three floral morphs. Lengths of the staminal filaments (long, intermediate, and short) were also significantly different. Also the floral nectary in L. <i>salicaria</i> is located in a depression formed at the interface of the hypanthium and the gynoecium. Several stomata are located at regular intervals along the nectary surface, and may constitute the escape route for floral nectar. No morphological differences in nectary structure were apparent among the three floral morphs.<p>Nectar secretion dynamics of L. <i>salicaria</i> were examined between the three floral morphs throughout two summer days in 2006. Peak average nectar volumes and nectar sugar quantities were detected at 3:00 pm, and, interestingly, no significant differences were detected between floral morphs, in accordance with nectary morphology. The estimated secretion rates for L. <i>salicaria</i> ranged from 61 83 µg of nectar sugar per flower per hour.<p>Hand-pollination experiments carried out over the summers of 2006 and 2007 at three field sites in and around Saskatoon have verified the strong self-incompatibility in the breeding system of this tristylous species. Intramorph pollination, using illegitimate pollen, did not result in fertilisation, whereas legitimate hand-pollination experiments yielded multiple pollen tubes at the style base, without exception.<p><i>Lythrum salicaria</i> in central Saskatchewan was visited by several bee taxa including honeybees (<i>Apis mellifera</i> L.), bumblebees (Bombus spp.), leafcutter bees (Megachile spp.), and sweat bees (Lasioglossum spp.). A single visit by <i>Anthophora furcata</i> (Panzer) was also recorded in 2007. Generally, bee visits led to high levels of pollination success as determined by fluorescence microscopy of pollen tubes following single insect visits to previously-unvisited flowers. However, most visits by hoverflies (Syrphidae) were non-pollinating. Visits by Pieris rapae (L.), yellowjacket wasps (Vespidae) and some non-syrphid flies (Diptera) also yielded no pollen tubes at the style base.<p>A study of the ultrastructure and development of the floral nectary of the purple loosestrife cultivar Morden Gleam (<i>Lythrum virgatum</i> L. x L. alatum Pursh.) showed that starch build up in pre-secretory nectary tissues declined throughout secretion, and is virtually absent in post-secretory nectary tissues. The lack of a direct vascular supply to the floral nectary suggests that the starch breakdown products likely make up most of the floral nectar carbohydrates. Surface features of the floral nectary in Morden Gleam closely resembled those of L. salicaria, located in the valley formed between the hypanthium and gynoecium. Nectary stomata, occasionally in pairs, likely serve as outlets for nectar in this cultivar.
39

Reproductive biology and nectary structure of <i>Lythrum</i> in central Saskatchewan

Caswell, Wade Devin 26 August 2008 (has links)
This project examined multiple aspects of the reproductive biology of the wetland invasive species, purple loosestrife (<i>Lythrum salicaria</i> L.), in central Saskatchewan. An examination of insect taxa visiting the three floral morphs of <i>Tristylous</i> L. <i>salicaria</i>, as well as a ranking of the pollination efficiency of individual insect species, an apparent first for L salicaria, was undertaken. Surface features of the floral nectary of L. <i>salicaria</i>, as well as floral nectar secretion dynamics, were also investigated. This project also re-visited some of the previous work done on this invasive species, including various floral organ morphometrics in relation to heterostyly, and aspects of the tristylous breeding system including self-fertilization, and fertilization potential of both illegitimate pollination and legitimate pollination.<p>The trimorphic nature of the sexual floral organs of L. <i>salicaria</i> were well defined in Saskatchewan. Significant differences in length (long-, intermediate- and short-style lengths) exist between all three floral morphs. Lengths of the staminal filaments (long, intermediate, and short) were also significantly different. Also the floral nectary in L. <i>salicaria</i> is located in a depression formed at the interface of the hypanthium and the gynoecium. Several stomata are located at regular intervals along the nectary surface, and may constitute the escape route for floral nectar. No morphological differences in nectary structure were apparent among the three floral morphs.<p>Nectar secretion dynamics of L. <i>salicaria</i> were examined between the three floral morphs throughout two summer days in 2006. Peak average nectar volumes and nectar sugar quantities were detected at 3:00 pm, and, interestingly, no significant differences were detected between floral morphs, in accordance with nectary morphology. The estimated secretion rates for L. <i>salicaria</i> ranged from 61 83 µg of nectar sugar per flower per hour.<p>Hand-pollination experiments carried out over the summers of 2006 and 2007 at three field sites in and around Saskatoon have verified the strong self-incompatibility in the breeding system of this tristylous species. Intramorph pollination, using illegitimate pollen, did not result in fertilisation, whereas legitimate hand-pollination experiments yielded multiple pollen tubes at the style base, without exception.<p><i>Lythrum salicaria</i> in central Saskatchewan was visited by several bee taxa including honeybees (<i>Apis mellifera</i> L.), bumblebees (Bombus spp.), leafcutter bees (Megachile spp.), and sweat bees (Lasioglossum spp.). A single visit by <i>Anthophora furcata</i> (Panzer) was also recorded in 2007. Generally, bee visits led to high levels of pollination success as determined by fluorescence microscopy of pollen tubes following single insect visits to previously-unvisited flowers. However, most visits by hoverflies (Syrphidae) were non-pollinating. Visits by Pieris rapae (L.), yellowjacket wasps (Vespidae) and some non-syrphid flies (Diptera) also yielded no pollen tubes at the style base.<p>A study of the ultrastructure and development of the floral nectary of the purple loosestrife cultivar Morden Gleam (<i>Lythrum virgatum</i> L. x L. alatum Pursh.) showed that starch build up in pre-secretory nectary tissues declined throughout secretion, and is virtually absent in post-secretory nectary tissues. The lack of a direct vascular supply to the floral nectary suggests that the starch breakdown products likely make up most of the floral nectar carbohydrates. Surface features of the floral nectary in Morden Gleam closely resembled those of L. salicaria, located in the valley formed between the hypanthium and gynoecium. Nectary stomata, occasionally in pairs, likely serve as outlets for nectar in this cultivar.
40

Própolis na dieta de abelhas Apis mellifera L. e seu efeito no sistema imune, expressão de genes após o desafio bacteriano e detoxificação frente ao agroquímico fipronil / Propolis in Apis mellifera L. diet and its effect on immune system and expression of genes after bacterial challenge and detoxification front of agrochemical fipronil

Souza, Edison Antonio de [UNESP] 16 December 2015 (has links)
Submitted by EDISON ANTONIO DE SOUZA null (esmidia@gmail.com) on 2016-01-06T16:51:45Z No. of bitstreams: 1 TESE_DOUTORADO_Edison_Souza.pdf: 947001 bytes, checksum: a8a8d690c84bc72a0b5e27d8ebeee92f (MD5) / Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2016-01-06T19:50:21Z (GMT) No. of bitstreams: 1 souza_ea_dr_bot_par.pdf: 573913 bytes, checksum: 30e1665c27c8c583a0b5ab8dc8bd89e0 (MD5) / Made available in DSpace on 2016-01-06T19:50:21Z (GMT). No. of bitstreams: 1 souza_ea_dr_bot_par.pdf: 573913 bytes, checksum: 30e1665c27c8c583a0b5ab8dc8bd89e0 (MD5) Previous issue date: 2015-12-16 / INFLUÊNCIA DO CONSUMO DA PRÓPOLIS NA EXPRESSÃO DE GENES RELACIONADOS AO SISTEMA IMUNOLOGICO DE ABELHAS Apis mellifera L. SUMETIDAS AO DESAFIO BACTERIANO. As abelhas Apis mellifera podem estar sujeitas a uma série de ameaças como parasitas e patógenos que acometem seu sistema imunológico. Tal fato torna necessária a busca por produtos naturais que possam contribuir com a melhora do sistema imune destes insetos, como a própolis. Diante do exposto, o objetivo foi analisar a influência do fornecimento da própolis em expressões de genes relacionados à imunidade de abelhas Apis mellifera L. submetidas ao desafio bacteriano. Ao longo de 30 dias, quatro colmeias receberam semanalmente os tratamentos com diferentes porcentagens de extrato alcoólico de própolis 30% (0%, 5%, 10%, 15%). O experimento foi casualizado em esquema fatorial 4 x 2 x 2x 3 (tratamentos x com ou sem bactéria x tempos x períodos), totalizando 48 amostras. Foram observadas as expressões dos genes abaecin, hymenoptaecin, apidaecin e defensin1. Como controle interno foi utilizado o gene actina. Os resultados foram comparados por ANOVA seguidos do teste de Tukey (P<0,05). Foram observadas alterações na expressão gênica das abelhas estudadas para todos os períodos e tratamentos, antes e após desafio bacteriano, para todos os genes propostos, sendo ainda verificada induções da expressão relativa nos três períodos. Conclui-se que nas condições do presente trabalho, a própolis pode induzir a expressão relativa dos genes abaecin, hymenoptaecin, apidaecin e defensin1, quando submetidas a desafio bacteriano. Entretanto, não se pôde caracterizar um tratamento com própolis que apresente uma maior expressão relativa para todos os genes simultaneamente. EFEITO DO CONSUMO DE PRÓPOLIS NAS ALTERAÇÕES COMPORTAMENTAIS E MORTALIDADE DE ABELHAS Apis mellifera L. SUBMETIDAS AO INSETICIDA FIPRONIL. Os inseticidas representam o maior risco direto para os polinizadores, como as abelhas Apis mellifera, sendo responsável pela redução das populações de abelhas e da produção apícola, tornando necessária a busca por substâncias que possam contribuir na melhora da saúde dessas abelhas, como a própolis. Este estudo verificou o efeito do consumo do extrato alcoólico de própolis no comportamento, quando submetidas a DL50 (0,2 µg/abelha) e subletal (1/500 DL50), e mortalidade das abelhas Apis mellifera L. quando submetidas a diferentes doses do inseticida fipronil (0,05; 0,1; 0,2; 0,3 e 0,4 µg/abelha). Ao todo foram utilizadas quatro colmeias, uma para cada tratamento (0, 5, 10 e 15% de inclusão de própolis), e em três períodos (0,15 e 30 dias) para verificar o efeito dos tratamentos ao longo do experimento. Para a realização dos testes de mortalidade e de alterações comportamentais foram selecionadas as abelhas campeiras das colmeias tratadas. Para o teste de mortalidade, os dados foram analisados em modelo linear misto generalizado, adicionado do Teste de Tukey (P<0,05) e a análise da avaliação das atividades comportamentais foi feita por (ANOVA) seguida do Teste de Tukey (P<0,05). As colmeias que consumiram própolis apresentaram menor taxa de mortalidade quando comparados com a colmeia controle (0%), com exceção no dia 0 em que a colmeia controle não diferiu do tratamento 10%. Verificou-se ainda que as abelhas que receberam o tratamento 10% apresentaram as menores taxas de mortalidade nos dias 15 e 30 de coleta. Além disso, foi observada mortalidade de 23% nas abelhas quando submetidas a DL50 do fipronil. Nos testes de alterações comportamentais e locomotoras não foram observadas influências dos tratamentos com própolis. Conclui-se que, para o presente estudo, a própolis influenciou na taxa de mortalidade e pode ter promovido um efeito protetor nas abelhas Apis mellifera L. quando submetidas a diferentes concentrações do inseticida fipronil, sendo ainda verificado que o tratamento 10% foi o mais eficaz, devido a ter apresentado as menores taxas de mortalidade nos dias 15 e 30. / INFLUENCE OF PROPOLIS CONSUMPTION IN GENES EXPRESSION RELATED TO IMMUNE SYSTEM OF Apis mellifera L. BEES SUBJECTED TO CHALLENGE BACTERIA. The Apis mellifera bees may be subject to a number of threats as parasites and pathogens that affect your immune system. This fact makes it necessary to look for natural products that can contribute to improving the immune system of these insects such as propolis. Given the above, the objective was to analyze the influence of the supply of propolis in gene expressions related to immunity of Apis mellifera L. bees subjected to bacterial challenge Over 30 days, four hives receive weekly treatments with different percentages of alcoholic extract of propolis 30% (0%, 5%, 10%, 15%). The experiment was randomized in a factorial 4 x 2 x 2x 3 (treatments x with or without bacteria x times x periods), totaling 48 samples. It was observed the expressions of abaecin, hymenoptaecin, apidaecin and defensing1 genes. As internal control was used actin gene. The results were compared by ANOVA followed by Tukey test (P <0.05). Alterations were observed in gene expression of bees studied for all periods and treatments before and after bacterial challenge for all proposed genes, were yet verified inductions of relative expression in the three periods. It is concluded that under the conditions of this study, propolis can induce the relative expression of genes abaecin, hymenoptaecin, apidaecin and defensin1, when subjected to bacterial challenge. However, it is not able to characterize a treatment with propolis presenting greater relative expression for all genes simultaneously. EFFECT OF PROPOLIS CONSUMPTION IN THE BEHAVIORAL CHANGES AND MORTALITY OF Apis mellifera L. BEES SUBMITTED TO PESTICIDE FIPRONIL. Pesticides pose the greatest direct risk for pollinators such as Apis mellifera bees, responsible for reducing bee populations and beekeeping, making it necessary to search for substances that can contribute to improving the health of these bees, such as propolis. Given this, the study found the effect of propolis alcoholic extract consumption behavior when subjected to DL50(0.2 µg/bee) and sublethal (1/500 DL50), and mortality of Apis mellifera L. bees submitted to different doses of the insecticide fipronil (0,05; 0.1, 0.2, 0.3 and 0.4 µg/bee). Four colonies were used, one for each treatment (0, 5, 10 and 15% inclusion of propolis), and in three periods (0,15 and 30 days) to determine the effect of the treatments throughout the experiment. To the achievement of mortality and behavioral changes tests the foraging bees from treated hives were selected. For the mortality test, the data were analyzed in generalized linear mixed model, added the Tukey test (P <0.05) and the analysis of the assessment of behavioral activities was made by (ANOVA) followed by Tukey test (P <0.05). Beehives who consumed propolis have a lower mortality rate compared to the hive control (0%), except on day 0 that the hive control did not differ from treatment 10%. It was also found that the hive that received treatment 10% was among the lowest mortality rates in the fifteenth and thirtieth collection day. Furthermore, the observed mortality was 23% in bees when subjected to LD50. In tests of locomotor and behavioral changes were observed influences of treatments with propolis. It concludes that, for this study, propolis influenced the mortality rate and may have promoted a protective effect on bees Apis mellifera L. when subjected to different concentrations of the insecticide fipronil, and also, that the treatment 10% was effective due to having presented the lowest mortality rates in the 15 and 30. However, treatments with propolis did not influence the behavioral and motor changes.

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