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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.
11

Interactions plante - pollinisateur : caractérisation de la qualité du pollen de deux cucurbitacées durant son ontogenèse, sa présentation et son transport sur le corps de l'abeille domestique / Plant – pollinator interactions : characterisation of pollen quality during its ontogenesis, its presentation and its transport on honey bee body in two cucurbitaceae

Dibos, Chloé 14 December 2010 (has links)
Chez de nombreuses Angiospermes, la pollinisation croisée est nécessaire pour le succès de la reproduction. La plupart de ces plantes ont évolué afin de favoriser la pollinisation entomophile, principalement assurée par les abeilles. C’est le cas des Cucurbitacées, dont le melon (Cucumis melo L.), importante culture du sud de la France et le concombre d’âne (Ecballium elaterium (L.) A. Rich.) plante spontanée endémique du bassin méditerranéen, les deux modèles de cette étude. Afin de mieux comprendre les relations plante-pollinisateur,nous avons choisi de caractériser le couple pollen de Cucurbitacées/abeille domestique (Apis mellifera L.) à travers la production de pollen, sa présentation sur la fleur et son transport sur l’abeille. Nous avons montré que, chez ces plantes, l’ontogenèse du pollen s’accompagne d’erreurs développementales conduisant à la formation de près de 3% de grains de pollen vides. De plus, nous avons mis en évidence que chez E. elaterium, des erreurs méiotiques entraînaient la formation de grains de pollen génétiquement anormaux qui pourraient être source d’autopolyploïdie. Chez C. melo, nos résultats ont révélé que la mise en contact du pollen avec le milieu environnant entraîne une baisse de 30% de sa viabilité, mais que celle-ci reste stable jusqu’à la fin de l’anthèse. L’aptitude à germer, quant à elle, finit d’être acquise juste avant anthèse et décroît de 12% en fin de période d’anthèse. Nous avons montré que le pollen de C. melo transporté sur le corps de l’abeille pouvait soit avoir une viabilité et une aptitude à germer préservée, probablement par protection contre la déshydratation, soit perdre quasi-totalement sa viabilité et son aptitude à germer. Enfin, nous avons détecté des composés biochimiques spécifiques des abeilles protégeant ou diminuant la qualité reproductrice du pollen / For many flowering plant species cross pollination is necessary to ensure reproductive success. Most of these plants have evolved to encourage insect pollination which is mainly carried out by bees. Such is the case of plants in the Cucurbitaceae family, including the cantaloupe (Cucumis melo L.), an important crop of the South of France, and squirting cucumber (Ecballium elaterium (L.) A. Rich.), a wild plant restricted to the Mediterranean Basin, the two vegetal models used in this study. To better understand plant-pollinator relations, we proposed to characterise the interaction between Cucurbitaceae pollen and the honey bee (Apis mellifera L.) through pollen production, its presentation and its transport on the honey bee body. Our results showed that developmental anomalies took place during pollen ontogenesis in these species leading to 3% of the pollen grains produced to be empty. Moreover, we demonstrated that meiotic abnormalities in E. elaterium leading to the production of genetically abnormal pollen grains could be a source of autopolyploidy. At anthesis in C. melo, our results showed that pollen viability decreased to 30% when pollen was exposed to environmental conditions, then remained stable during the period of anthesis.The ability for pollen to germinate was completed just before anthesis then decreased to 12% at the end of anthesis. We determined that viability and germinability of cantaloupe pollen carried on the honey bee body can be enhanced or decreased according to which specific honey bee biochemical compounds were detected
12

Características físico-químicas de méis de abelha (Apis mellifera L.) em diferentes condições de armazenamento. / Physicochemical characteristics of bee honeys (Apis mellifera L.) under different storage conditions.

MELO, Zilmar Fernandes Nóbrega. 06 June 2018 (has links)
Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-06-06T18:24:16Z No. of bitstreams: 1 ZILMAR FERNANDES NÓBREGA MELO - DISSERTAÇÃO PPGEA 2002..pdf: 14604622 bytes, checksum: 92a403c722a2a592fbb333f263c9b64f (MD5) / Made available in DSpace on 2018-06-06T18:24:16Z (GMT). No. of bitstreams: 1 ZILMAR FERNANDES NÓBREGA MELO - DISSERTAÇÃO PPGEA 2002..pdf: 14604622 bytes, checksum: 92a403c722a2a592fbb333f263c9b64f (MD5) Previous issue date: 2002-08 / Estudou-se o armazenamento de méis de abelhas africanizadas (Apis mellifera L.) coletados no brejo e cariri do estado da Paraíba. Utilizou-se, quanto à florada, dois tipos de mel de abelha (mel de florada silvestre e mel de florada de baraúna), armazenados sob 3 diferentes condições de embalagens (El - recipiente de polietileno opaco e exposto à luz e temperatura ambiente; E2 - recipiente de polietileno exposto à temperatura ambiente e ao abrigo da luz; E3 - recipiente em vidro translúcido exposto à temperatura e luz ambiente), ao longo de 180 dias, tendo sido estes submetidos a análises físico-químicas mensalmente, com a finalidade de observar as possíveis alterações nas características físico-químicas (°Brix, Umidade, Cinzas, Hidroximetilfurfural-HMF, Açúcares redutores, Sacarose aparente, Atividade diastásica e pH), objetivando verificar a eficiência destas embalagens no índice de qualidade dos méis. As análises físico-químicas dos méis foram feitas seguindo o recomendado pela Instrução Normativa do Ministério da Agricultura e do Abastecimento (Brasil, 2000). Os valores médios encontrados, ao longo do Armazenamento, para o °Brix do mel silvestre ficaram no intervalo de variação de 78,03 a 78,42 °Brix e o da florada de baraúna de 81,31 a 81,63 °Brix e não houve diferença significativa entre as embalagens ao longo do armazenamento. Os níveis de Umidade (%) para os méis silvestres e de baraúna foram 19,48 a 20,48 % e 16,25 a 16,70 %, respectivamente. Os valores Cinzas e de Sólidos Insolúveis não apresentara diferenças significativas no tempo e/ou nas embalagens. Os níveis no índice de HMF ficaram no intervalo de variação de 4,57 a 10,17 mg/kg de mel e 1,08 a 7,12 mg/kg, no mel Silvestre e no mel de baraúna, respectivamente. Pelas análises estatísticas, verificou-se, para os dois méis, diferença significativa a 1% de probabilidade e que as médias diferem entre si. Houve para o HMF, diferença significativa entre as embalagens e a E2 foi a mais eficiente no controle do aumento deste índice nos dois méis estudados. Os valores médios de Açúcares Redutores ficaram entre 74,09 e 76,41 % no mel Sivestre e entre 62,51 e 64,80 % para o mel de baraúna. Os valores de Sacarose Aparente ficaram entre 2,18 a 3,01 % para o mel silvestre e entre 2,40 e 2,89 % no mel de baraúna. Os méis sofreram pequena variação no tempo e as embalagens não influenciaram sobre a sacarose, nos dois méis. A Atividade Diastásica (DN) no mel Sivestre ficou no intervalo de variação de 13,37 a 18,71 DN e 9,14 a 13,25 DN no mel de baraúna. As análises estatísticas para os dois méis foram significativas ao nível de 1% de probabilidade e no teste de Tukey, as médias diferiram entre si, e a embalagem E2, nos dois méis analisados, mostrou-se mais eficiente na desaceleração do índice de Diástase em relação a El e E3. Quanto ao pH, o mel Sivestre foi mais ácido (3,42 a 3,55) do que o mel de baraúna (3,85 a 4,15). Todas as amostras encontram-se dentro dos padrões exigidos pelo Ministério da Agricultura e do Abastecimento. Do resultado final, concluiu-se que houve maior eficiência na embalagem E2, que contribuiu para a desaceleração do ritmo no índice de diástase. Observou-se que o índice de acidez livre aumentou ao longo do armazenamento. / The storage of african bees honeys (Aipis mellifera L.) which were collected from slough and cariri in Paraíba state was studied. Considering the bloomed, two kinds of bee honey (wild bloomed honey and baraúna bloomed honey) were used and storaged under three different conditions of packages ( Ei - opaque polyethylene container, that was under environment light and temperature; E2 - polyethylene container that was under environment temperature but it wasn't under light environment; E3 - translucent glass container which was exposed to environment temperature and light). These honeys stayed 180 days in packages and their physiochemical characteristics were analysed monthly to observe the possible alterations of them ( 0 Brix, Humidity, Ashes, Hydroximethylfurfurol - HMF, Reducers Sugar, Apparent Saccharose, Diastasic Activity and pH) to verify the efficiency of these packages in the honeys qualities index. The physiochemical analyses of the honeys were done according to the Normative Instruction of the Agriculture and Provisioning Ministry (Brazil, 2000). During the storage time, the médium found values to the 0 Brix of the wild bloomed honey were between 78.03 and 78.42 0 Brix and the ones of the baraúna bloomed honey were between 81.31 and 81.63 0 Brix and there wasn't significant difference among the packages during the storage period. The Humidity rates (%) were between 19.48 and 20.48% to the wild honey and between 16.25 and 16.70 to the baraúna honey. There were no significant differences of the Ashes and Insoluble Solids values on their time and packages. The rates in the HMF index varied from 4.57 to 10.17 mg/Kg of honey and from 1.08 to 7.12 mg/Kg, to the wild and baraúna honeys, respectively. According to the statistics analyses, a significant difference of 1% of probability for both honeys was verified, besides the averages are different among them. To the HMF, there was a significant difference among the packages and the E2 was the most efficient to the control of the increase of this index in both studied honeys. The médium values of the Reducers Sugar were between 74.09 and 76.41% to the wild honey and they were between 62.51 and 64.80% to the baraúna honey. The Apparent Saccharose values were between 2.18 and 3.01% to the wild honey and they were between 2.40 and 2.89 to de baraúna honey. The honeys had a little time variation and the packages had no influence on the saccharose, in both honeys. The Diastasic Activity (DN) on the Wild honey varied from 13.37 to 18.71 DN and the variation of the baraúna honey was from 9.14 to 13.25 DN. The statistics analyses were significative at 1% of probability and at the Tukey test for both honeys, the averages were diferent among them and the E2 package was more efficient than the Ei and E3 to the unacceleration of the diástase index for both honeys. Analysing the pH, the wild honey was more acid (3.42 to 3.55) than the baraúna honey (3.85 to 4.15). Ali the samples are according to the Agriculture and Provision Ministry patterns. According to the final result, it's conclued that there was a bigger efficiency of the E2 package and it contributed to the rhythm unaceleration in the distasic index. It was observed that the free acidity index increased during the storage period.
13

Avaliação das características genéticas de abelhas africanizadas (Apis mellifera L.) importantes na seleção de rainhas matrizes para a produção de mel / Evaluation of genetic characteristics of africanized bees (Apis mellifera L.), important in selecting matrix queens for honey production

Gomes, Renata Valéria Regis de Sousa 02 May 2016 (has links)
Submitted by Socorro Pontes (socorrop@ufersa.edu.br) on 2017-04-11T16:57:51Z No. of bitstreams: 1 RenataVRSG_TESE.pdf: 4187159 bytes, checksum: 1407c0df06b55e7b10b6605b6b21cbe7 (MD5) / Approved for entry into archive by Vanessa Christiane (referencia@ufersa.edu.br) on 2017-04-13T15:06:15Z (GMT) No. of bitstreams: 1 RenataVRSG_TESE.pdf: 4187159 bytes, checksum: 1407c0df06b55e7b10b6605b6b21cbe7 (MD5) / Approved for entry into archive by Vanessa Christiane (referencia@ufersa.edu.br) on 2017-04-13T15:06:23Z (GMT) No. of bitstreams: 1 RenataVRSG_TESE.pdf: 4187159 bytes, checksum: 1407c0df06b55e7b10b6605b6b21cbe7 (MD5) / Made available in DSpace on 2017-04-13T15:06:34Z (GMT). No. of bitstreams: 1 RenataVRSG_TESE.pdf: 4187159 bytes, checksum: 1407c0df06b55e7b10b6605b6b21cbe7 (MD5) Previous issue date: 2016-05-02 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This work aimed to evaluate africanized bee (Apis mellifera L.) phenotypic characteristics, important in selecting matrix queens for honey production. Thirty africanized bee (Apis mellifera L.) colonies were transferred from partner beekeeping apiaries in coastal zone and South Zona da Mata of Pernambuco to experimental apiary of Animal Science Department (AEDZ/UFRPE). Colonies were fortnightly evaluated in the period from January 2014 to February 2016 and data of 89 queens of colonies or families were recorded. Energy and protein food was provided in off-season period. Infestation rate in colonies with Varroa destructor and infection degree with Nosema were verified, as well as hygienic behavior, queen egg laying, defensiveness and honey production tests were carried out in the first experimental phase and selection index (IS) was obtained of analyzed colonies. For the 2nd experimental phase, 1st, 2nd and 3rd generation queens were produced; daughters of matrixes with IS ≥ 8.0 and honey production was evaluated. Sixty-two out of 89 queens observed died naturally, presenting average longevity of 6.4 ± 2.9 months. Natural reproduction peak period is between September and December. The queen perform egg laying all months of the year, and as temperature increases and humidity and rainfall decrease, queen oviposition intensity is higher; thus brood comb increases. The diet used showed economic viability, avoided swarm loss and stimulated queen egg laying. Low level of Varroatose (2.92% ± 2.02%) and low intensity of Nosema infection were found. Success in queen cell production was 98% in acceptance of transferred larvae. Genetic gain was observed of 0.7 Kg in honey production at colonies with 3rd generation queens; which represents increasing of 5.4% of honey production, related to matrix colonies and 49.2% compared to production in partner beekeeping apiaries. These results are very encouraging, leading us to believe in breeding program success, using the variables and calculation format for selection index used in this work and give us subsides for possible adjustments in management of production apiaries, in accordance with environmental conditions of this region, aiming at professional beekeeping growth and increased honey production / Este trabalho teve como objetivo avaliar as características fenotípicas de abelhas africanizadas (Apis mellifera L.) importantes na seleção de rainhas matrizes para a produção de mel. Foram transferidas 30 colônias de abelhas africanizadas (Apis mellifera L.) dos apiários de apicultores colaboradores da região do litoral e zona da mata sul de Pernambuco para o apiário experimental do Departamento de Zootecnia (AEDZ/UFRPE). As colônias foram avaliadas quinzenalmente no período de janeiro de 2014 a fevereiro de 2016 e foram registrados dados de 89 rainhas de colônias ou famílias. Foi administrado alimentação energética e proteica no período de entressafra. Foi verificado o nível de infestação das colônias com Varroa destructor e Nosema e realizado os testes de comportamento higiênico, postura da rainha, defensividade e produção de mel na 1ª fase experimental e obteve-se o índice de seleção (IS) das colônias analisadas. Para 2ª fase experimental foram produzidas rainhas de 1ª, 2ª e 3ª geração filhas das matrizes com IS ≥ 8,0 e avaliou-se a produção de mel. Das 89 rainhas observadas, 62 morreram naturalmente apresentando longevidade média de 6,4 ± 2,9 meses. A época de pico da reprodução natural é entre os meses de setembro a dezembro. A rainha realiza postura todos os meses do ano, sendo que à medida que a temperatura aumenta e a umidade e o índice pluviométrico diminuem, maior é a intensidade de ovoposição da rainha, consequentemente aumenta o número de quadros com crias. A dieta utilizada apresentou viabilidade econômica, evitou a perda dos enxames e estimulou a postura da rainha. Foram encontrados um nível baixo de varroatose (2,92% ± 2,02%) e baixa intensidade de infecção por Nosema. O sucesso na produção de realeiras foi de 98% na aceitação das larvas transferidas. Observou-se um ganho genético de 0,7 Kg na produção de mel nas colônias com rainhas de 3ª geração, o que representa aumento de 5,4% na produção de mel em relação as colônias matrizes e 49,2% comparada a produção nos apiários dos apicultores parceiros. Esses resultados são muito estimulantes levando-se a acreditar no sucesso do programa de melhoramento aplicado, utilizando-se as variáveis e a forma de cálculo para o índice de seleção utilizados no presente trabalho e nos dá subsídios para possíveis adequações no manejo dos apiários de produção, em conformidade com as condições ambientais dessa região, visando o crescimento profissional da atividade apícola e o aumento da produção de mel / 2017-04-11
14

Características físico-químicas, microbiológicas e polínicas de amostras de méis de Apis mellifera L., 1758 (Hymenoptera: Apidae) dos estados do Ceará e Piauí / Physicochemical, microbiological and pollinic characteristics of Apis mellifera L., 1758 (Hymenoptera: Apidae) honey samples from the states of Ceara and Piaui

Sodré, Geni da Silva 29 April 2005 (has links)
Com o objetivo de determinar as características físico-químicas, microbiológicas e a origem floral de méis produzidos por Apis mellifera L., 1758, foram determinados no Laboratório de Insetos Úteis do Departamento de Entomologia, Fitopatologia e Zoologia Agrícola da Escola Superior de Agricultura "Luiz de Queiroz" e no Laboratório de Instrumentação Nuclear do Centro de Energia Nuclear na Agricultura, USP: açúcares totais, açúcares redutores, sacarose aparente, umidade, atividade diastásica, hidroximetilfurfural, proteína, cinzas, pH, acidez, índice de formol, condutividade elétrica, viscosidade, cor, elementos químicos (K, Ca Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, Se, Br Rb, Sr, Ba, Hg e Pb), microorganismos e realizadas análises polínicas de 58 amostras de méis colhidas no Estados do Ceará (20 amostras) e Piauí (38 amostras). Os resultados demonstraram que a maioria dos valores médios para cada parâmetro físico-químico das amostras analisadas encontram-se dentro dos limites estabelecidos pela legislação vigente entretanto verifica-se, para amostras do Estado do Piauí, valor médio para a atividade diastásica abaixo do estabelecido. Para os elementos químicos foram verificados valores acima dos estabelecidos para os elementos Cr, Ni, Zn e Pb. As amostras estudadas foram negativas para coliformes totais, entretanto, foram constatados fungos e leveduras. Pelas análises polínicas dos méis foram considerados como espécies vegetais dominantes para o Estado do Ceará a Mimosa caesalpiniaefolia, M. verrucosa, Borreria sp. I, Serjania sp. e tipo Fabaceae. No Estado do Piauí a Piptadenia sp., M. caesalpiniaefolia, M. verrucosa, Croton urucurana e Tibouchina sp.. / This research deals with the physicochemical, microbiological and pollinic characteristics of 58 samples of Apis mellifera L., 1758 (Hymenoptera: Apidae) honey from the Brazilian states of Ceara (20 samples) and Piaui (38 samples). The following parameters were determined: total sugars, reducing sugars, apparent sucrose, humidity, diastase activity, hydroxymethylfurfural, protein, ashes, ph, acidity, formol index, electrical conductivity, viscosity, color, chemical elements (K, Ca, Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, Se, Br, Rb, Sr, Ba, Hg, Pb) and microrganisms. The experiments were set in the "Laboratorio de Insetos Úteis", Department of Entomology, Phytopathology and Agricultural Zoology and in the "Laboratorio de Instrumentação Nuclear, Centro de Energia Nuclear na Agricultura" University of São Paulo, in Piracicaba, State of São Paulo. The results have indicated that most of the mean values for each physicochemical parameter are In accordance with the limits established by the Brazilian the diastase activity is below those limits. Concerning the chemical elements, one observed values above those limits, as follows: Cr, Ni, Zn and Pb. The samples were negative for total coliforms. However fungi and yeast were detected. The pollinic analyses showed that the dominant plant species of the Ceara State were Mimosa caesalpiniaefolia, M. verrucosa, Borreria sp., Serjania sp. and type Fabaceae. The dominant plant species of the Piaui State were Piptadenia sp., M. caesalpiniaefolia, M. verrucosa, Croton urucurana and Tibouchina sp..
15

Características físico-químicas, microbiológicas e polínicas de amostras de méis de Apis mellifera L., 1758 (Hymenoptera: Apidae) dos estados do Ceará e Piauí / Physicochemical, microbiological and pollinic characteristics of Apis mellifera L., 1758 (Hymenoptera: Apidae) honey samples from the states of Ceara and Piaui

Geni da Silva Sodré 29 April 2005 (has links)
Com o objetivo de determinar as características físico-químicas, microbiológicas e a origem floral de méis produzidos por Apis mellifera L., 1758, foram determinados no Laboratório de Insetos Úteis do Departamento de Entomologia, Fitopatologia e Zoologia Agrícola da Escola Superior de Agricultura "Luiz de Queiroz" e no Laboratório de Instrumentação Nuclear do Centro de Energia Nuclear na Agricultura, USP: açúcares totais, açúcares redutores, sacarose aparente, umidade, atividade diastásica, hidroximetilfurfural, proteína, cinzas, pH, acidez, índice de formol, condutividade elétrica, viscosidade, cor, elementos químicos (K, Ca Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, Se, Br Rb, Sr, Ba, Hg e Pb), microorganismos e realizadas análises polínicas de 58 amostras de méis colhidas no Estados do Ceará (20 amostras) e Piauí (38 amostras). Os resultados demonstraram que a maioria dos valores médios para cada parâmetro físico-químico das amostras analisadas encontram-se dentro dos limites estabelecidos pela legislação vigente entretanto verifica-se, para amostras do Estado do Piauí, valor médio para a atividade diastásica abaixo do estabelecido. Para os elementos químicos foram verificados valores acima dos estabelecidos para os elementos Cr, Ni, Zn e Pb. As amostras estudadas foram negativas para coliformes totais, entretanto, foram constatados fungos e leveduras. Pelas análises polínicas dos méis foram considerados como espécies vegetais dominantes para o Estado do Ceará a Mimosa caesalpiniaefolia, M. verrucosa, Borreria sp. I, Serjania sp. e tipo Fabaceae. No Estado do Piauí a Piptadenia sp., M. caesalpiniaefolia, M. verrucosa, Croton urucurana e Tibouchina sp.. / This research deals with the physicochemical, microbiological and pollinic characteristics of 58 samples of Apis mellifera L., 1758 (Hymenoptera: Apidae) honey from the Brazilian states of Ceara (20 samples) and Piaui (38 samples). The following parameters were determined: total sugars, reducing sugars, apparent sucrose, humidity, diastase activity, hydroxymethylfurfural, protein, ashes, ph, acidity, formol index, electrical conductivity, viscosity, color, chemical elements (K, Ca, Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, Se, Br, Rb, Sr, Ba, Hg, Pb) and microrganisms. The experiments were set in the "Laboratorio de Insetos Úteis", Department of Entomology, Phytopathology and Agricultural Zoology and in the "Laboratorio de Instrumentação Nuclear, Centro de Energia Nuclear na Agricultura" University of São Paulo, in Piracicaba, State of São Paulo. The results have indicated that most of the mean values for each physicochemical parameter are In accordance with the limits established by the Brazilian the diastase activity is below those limits. Concerning the chemical elements, one observed values above those limits, as follows: Cr, Ni, Zn and Pb. The samples were negative for total coliforms. However fungi and yeast were detected. The pollinic analyses showed that the dominant plant species of the Ceara State were Mimosa caesalpiniaefolia, M. verrucosa, Borreria sp., Serjania sp. and type Fabaceae. The dominant plant species of the Piaui State were Piptadenia sp., M. caesalpiniaefolia, M. verrucosa, Croton urucurana and Tibouchina sp..
16

Interactions plante - pollinisateur : caractérisation de la qualité du pollen de deux cucurbitacées durant son ontogenèse, sa présentation et son transport sur le corps de l'abeille domestique

Dibos, Chloé 14 December 2010 (has links) (PDF)
Chez de nombreuses Angiospermes, la pollinisation croisée est nécessaire pour le succès de la reproduction. La plupart de ces plantes ont évolué afin de favoriser la pollinisation entomophile, principalement assurée par les abeilles. C'est le cas des Cucurbitacées, dont le melon (Cucumis melo L.), importante culture du sud de la France et le concombre d'âne (Ecballium elaterium (L.) A. Rich.) plante spontanée endémique du bassin méditerranéen, les deux modèles de cette étude. Afin de mieux comprendre les relations plante-pollinisateur,nous avons choisi de caractériser le couple pollen de Cucurbitacées/abeille domestique (Apis mellifera L.) à travers la production de pollen, sa présentation sur la fleur et son transport sur l'abeille. Nous avons montré que, chez ces plantes, l'ontogenèse du pollen s'accompagne d'erreurs développementales conduisant à la formation de près de 3% de grains de pollen vides. De plus, nous avons mis en évidence que chez E. elaterium, des erreurs méiotiques entraînaient la formation de grains de pollen génétiquement anormaux qui pourraient être source d'autopolyploïdie. Chez C. melo, nos résultats ont révélé que la mise en contact du pollen avec le milieu environnant entraîne une baisse de 30% de sa viabilité, mais que celle-ci reste stable jusqu'à la fin de l'anthèse. L'aptitude à germer, quant à elle, finit d'être acquise juste avant anthèse et décroît de 12% en fin de période d'anthèse. Nous avons montré que le pollen de C. melo transporté sur le corps de l'abeille pouvait soit avoir une viabilité et une aptitude à germer préservée, probablement par protection contre la déshydratation, soit perdre quasi-totalement sa viabilité et son aptitude à germer. Enfin, nous avons détecté des composés biochimiques spécifiques des abeilles protégeant ou diminuant la qualité reproductrice du pollen
17

Influence de l'alimentation pollinique sur la santé de l'abeille domestique, Apis mellifera L. / Influence of pollen diet on the honeybee health, in Apis mellifera L.

Di pasquale, Garance 01 December 2014 (has links)
La nutrition est l'ensemble des processus par lesquels un être vivant transforme des aliments pour assurer son fonctionnement. Etudier la nutrition d’un organisme permet de comprendre les rapports entre la nourriture consommée et la santé de l’individu. L'ensemble des organes assurant l'extraction d'énergie est le système digestif, qui transforme les sucres en glucose, les corps gras en acides gras, et les protéines en acides aminés. L’objectif de cette étude est de déterminer l’influence que peut avoir la nutrition pollinique sur la santé de l’abeille domestique, Apis mellifera L.. Pour assurer cette nutrition, l’abeille est inféodée aux ressources florales. Du pollen récolté sur les plantes à fleurs, l’organisme puise les corps gras (ou lipides), les vitamines et les protéines. Or l’accès à ces ressources est variable en qualité, en quantité, et en diversité selon le temps et le milieu. Des problèmes de mortalités et affaiblissements des colonies sont observés depuis une vingtaine d’années, et l’une des causes suspectées est le manque de disponibilité et la faible valeur nutritionnelle des ressources polliniques en zones agricoles céréalières. Nous avons donc testé en conditions contrôlées les effets de la quantité, la qualité et la diversité pollinique sur la physiologie d’abeilles nourrices, sur leur immunité, ainsi que sur leur survie. La nutrition jouant un rôle essentiel dans la prévention de nombreuses maladies, les effets de l’alimentation pollinique ont été déterminés en présence ou non d’un stresseur biotique, Nosema ceranae, dont la prévalence dans les colonies est très élevée. Il s’agit d’une microsporidie invasive qui se développe dans l’intestin de son hôte, provoquant divers effets sublétaux et létaux. Etant donné que la valeur nutritionnelle d’un aliment dépend de sa composition mais aussi de sa digestibilité, une troisième partie porte sur l’influence que peut avoir le stresseur sur les capacités de digestion des protéines contenues dans le pollen par l’abeille. Nos résultats apportent des connaissances sur l’impact d’une déplétion en pollen que peuvent subir les colonies dans un paysage d’agriculture intensive. En effet, des abeilles carencées à plus ou moins 60 %, comme cela peut être observé entre deux cultures à floraison massives, subissent des perturbations au niveau individuel (perturbations du développement physiologique des abeilles nourrices, diminution de leur survie), ce qui peut les rendre moins performantes et plus sensibles aux stress présents dans l’environnement. De plus, nous avons pu démontrer que la valeur nutritionnelle des pollens, influence la tolérance des abeilles à Nosema ceranae. La qualité d’un pollen se définit par sa composition chimique totale (protéines, acides aminés, lipides, vitamines, sucres, etc…), et non pas uniquement par sa teneur en protéines ou acides aminés essentiels. Notre étude met d’ailleurs en évidence l’effet négatif d’une alimentation à base de pollen de maïs sur le développement des glandes hypopharyngiennes, l’expression du gène de la vitellogénine, et la survie des abeilles. Au regard de la présence élevée de cette culture dans les zones d’agriculture intensive et sa haute exploitation par les butineuses, nos résultats sont discutés en fonction des répercussions envisagées sur les colonies. Dans ces milieux, la diversité des ressources polliniques, par l’apport de pollens de qualité, compense la pauvreté nutritionnelle d’autres pollens. Dans nos conditions, nous pouvons observer la plus-value d’une alimentation pollinique polyflorale chez des abeilles infestées par Nosema. Les mesures agro-écologiques œuvrant pour régulariser dans le temps les apports polliniques aux colonies, et pour leur offrir une diversité alimentaire participent donc à renforcer leur capacité à lutter contre les stress présents dans l’environnement. / Nutrition is the set of processes by which a living organism transforms food for its functions. Studying nutrition allows to understanding the relationship between food intake and health of the individual. All organs for extracting energy are the digestive system, which converts sugars into glucose, fats into fatty acids, and proteins into amino acids. The objective of this study is to determine the possible influence of pollen nutrition on the honeybee health, Apis mellifera L. To ensure that nutrition, the bee is subservient to floral resources. Of pollen collected from the flowering plants, the body draws fats (or lipids), vitamins and proteins. Access to these resources is variable in quality, quantity, and diversity depending on the time and the environment. Problems of mortality and weakening of colonies are observed for some twenty years, and one of the suspected causes is the lack of availability and low nutritional value of pollen resources in agricultural areas. We therefore tested under controlled conditions the effects of quantity, quality and diversity of pollen on nurse worker physiology and on their immunity, as well as their survival. Nutrition plays a vital role in the prevention of many diseases, the effects of pollen diet were determined in the presence or absence of a biotic stressor, Nosema ceranae, whose prevalence in the colonies is very high. It is an invasive microsporidia that develops in the intestine of its host, causing various sublethal and lethal effects. Since the nutritional value of a food depends on its composition but also its digestibility, a third part focuses on the possible influence of the stressor on bee ability digestion of the proteins provided by the pollen.Our results provide knowledge on the impact of pollen depletion that may undergo the colonies in an intensive agricultural landscape. Indeed, bees starved to roughly 60%, as can be observed between two cultures massive flowering undergo disturbances at individual level (disturbances of nurse worker physiological development, reduced survival), which may make them less efficient and more susceptible to stress from the environment. In addition, we demonstrated that the nutritional value of pollen influences the Nosema ceranae‘s bee tolerance. The pollen quality is determined by the total chemical composition (proteins, amino acids, lipids, vitamins, sugars, etc ...), not only by its content of essential amino acids or proteins. Our study also demonstrated the negative effect of a diet based on maize pollen on hypopharyngeal glands development, the vitellogenin gene expression, and the bee survival. In view of the high presence of this culture in intensive agriculture areas and high exploitation by foragers, our results are discussed in terms of their impact on the proposed settlements. In these environments, the diversity of pollen resources by providing pollen of quality compensates nutritional poverty of other pollens. In our conditions, we can observe the gain of power of a polyfloral pollen in Nosema infested bees. Agro-ecological measures working to regularize, in time, the pollen contributions to the colonies, and to provide them with food diversity thus participate in building their capacity to fight against stress in the environment
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Toxicidade de neonicotinóides sobre abelhas (Apis mellifera). / Toxicity neonicotinoids on honeybees (Apis mellifera).

ARAÚJO, Whakamys Lourenço de. 17 May 2018 (has links)
Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-05-17T18:15:59Z No. of bitstreams: 1 WHALAMYS LOURENÇO DE ARAÚJO - DISSERTAÇÃO PPGHT 2015..pdf: 998803 bytes, checksum: 00aca588e4e5182e7ebe10263ae94f8c (MD5) / Made available in DSpace on 2018-05-17T18:15:59Z (GMT). No. of bitstreams: 1 WHALAMYS LOURENÇO DE ARAÚJO - DISSERTAÇÃO PPGHT 2015..pdf: 998803 bytes, checksum: 00aca588e4e5182e7ebe10263ae94f8c (MD5) Previous issue date: 2015 / Capes / O cultivo do meloeiro (Cucumis melo L.) é de grande importância para a economia brasileira. Seu cultivo tem demonstrado significativa expansão nas duas últimas décadas, especialmente nas regiões Semiáridas do Nordeste. Apesar dos fatores favoráveis à produtividade do meloeiro, vale salientar fatores limitantes, destacando-se os danos ocasionados por pragas que destroem o cultivo e, consequentemente, diminuindo a colheita, obrigando que medidas de controle sejam adotadas. Entres estas, estão aplicações de inseticidas químicos, entre eles os neonicotinoides. Estudos têm demonstrado os danos colaterais destes inseticidas a insetos benéficos como abelhas, que por sua vez são de fundamental importância para a polinização de 90% das angiospermas, principalmente para o melão. Este trabalho teve como objetivo avaliar a toxicidade de neonicotinoides empregados para o controle de pragas na cultura do meloeiro à abelhas A. mellifera Linnaeus. Os bioensaios foram realizados em laboratório, sendo tomadas medidas repetidas no tempo de mortalidade para os produtos comerciais Actara 250 WG (tiametoxam), Evidence 700 WG (imidacloprid), Mospilan (acetamipride) e Orfeu (acetamipride). A exposição das abelhas aos compostos foi realizada por meio de pulverização e ingestão de alimento contaminado com as maiores e menores doses recomendadas pelos fabricantes. Independente do modo de exposição, tiametoxam, imidaclopride e acetamipride (duas formulações) foram tóxicos, diminuindo o tempo de vida útil das abelhas em até 1, 2, 11 e 11 dias, respectivamente, quando comparados com a testemunha, que por sua vez sobreviveram 18 dias, em média. O inseticida tiametoxam foi extremamente tóxico quando pulverizado sobre as abelhas, bem como quando contaminante da dieta ingerida. O imidaclopride também apresentou toxicidade em ambos os experimentos, sendo depois do tiametoxam o mais tóxicos. O inseticida acetamipride apresentou toxicidade, porém não tão alta, quanto às observadas com o tiametoxam e o imidaclopride. / The cultivation of melon (Cucumis melo L.) is of great importance for the Brazilian economy, especially in semiarid regions of the Northeast. Despite the favorable factors to the yield of melon other limiting factors have been highlighted as the damage caused by pests, which undertake to harvest, requiring that control measures are adopted. Among these are applications of chemical insecticides, including the neonicotinoids. Studies have shown the collateral damage of these insecticides to beneficial insects like bees, important pollinators of 90% of angiosperms, mainly to melon. The objective of this study was to evaluate the toxicity of neonicotinoids used for pest control in the melon crop to Linnaeus honeybees. Bioassays were performed in the laboratory, being taken repeated measures in time to mortality commercial products Actara 250 WG (thiamethoxam), Evidence 700 WG (imidacloprid), Mospilan (acetamiprid) and Orpheus (acetamiprid) (two formulations). The exposure of bees to the compounds was performed by spraying and ingestion of food contaminated with higher and lower doses recommended by the manufacturers. Regardless of the exposure mode, all insecticides were toxic, reducing the useful life of bees within 1, 2 and 11 days, respectively, compared with the control (distilled water + pure candy), which survived 18 days, average . The insecticide thiamethoxam in both experiments and doses, was extremely toxic; as well as Imidacloprid, the second most toxic. The Acetamiprid insecticide, in both formulations showed toxicity, but not so high as those observed with other insecticides in the study.

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