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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.
281

NOSEMA CERANAE IN WESTERN HONEY BEES (APIS MELLIFERA): BIOLOGY AND MANAGEMENT

Williams, Geoffrey Rhys 27 March 2013 (has links)
Western honey bees (Apis mellifera; hereafter honey bees) provide vital pollination services to global agriculture and biodiversity. However in recent years they have experienced severe population declines in many regions of the northern hemisphere. Although causes of these honey bee declines are not well understood, multiple pressures such as changes in land-use and climate, management issues, and introduced parasites are believed to be responsible. First described in honey bees in 2006 during a period of high colony mortalities, the microsporidian gut parasite Nosema ceranae became of great concern. In this dissertation I investigated the distribution, management, virulence, and inter-specific interactions of this introduced species. First, I described and clarified the multiple pressures believed to influence honey bee health, including N. ceranae, especially in relation to the mysterious phenomenon Colony Collapse Disorder. I then surveyed colonies in Maritime Canada for N. ceranae and the historic honey bee microsporidian Nosema apis. Although both species were present at a regional scale, intensive sampling in Nova Scotia revealed that N. ceranae was highly prevalent compared to the historic congener. Next, I investigated two potential management options for the parasite. Chemotherapy using the fungicide fumagillin reduced N. ceranae spore intensity but had no effect on colony survival, and indoor over-wintering did not reduce spore intensity but was associated with increased colony survivorship in spring. Using a comparative approach, I observed that N. ceranae infection significantly reduced honey bee longevity in the laboratory but did not influence overall colony health or strength in the field. Last, a laboratory study demonstrated reduced spore production during N. ceranae and N. apis co-infection, possibly due to inter-specific competition that has resulted in the displacement of the historic Nosema species by N. ceranae in many global regions. This dissertation provides crucial information on biology and management of N. ceranae that can be used towards the development of an integrated pest management strategy, and for future studies investigating factors that may influence the parasite’s distribution, virulence, and inter-specific interactions.
282

Evaluation of the Fungi Beauveria bassiana, Metarhizium anisopliae, and Clonostachys rosea as Bio-control Agents against the Honey Bee Parasitic Mite, Varroa destructor

Sinia, Alice 08 1900 (has links)
Laboratory bioassay was used to determine the pathogenicity of nine isolates of fungi of the genera Metarhizium, Beauveria and Clonostachys to the parasitic mite, Varroa destructor. All nine isolates were pathogenic to V. destructor with Metarhizuim anisopliae UAMH 9198, Clonostachys rosea UAMH 9161 and Beauveria bassiana GHA being the most pathogenic within their respective species. Metarhizium anisopliae UAMH 9198 was more lethal to V. destructor than B. bassiana GHA and C. rosea UAMH 9161 with LC50 values of 1.6 x 10(5), 9.6 x 10(6) and 5.4 x 10(6) conidia/mL, respectively. Metarhizium anisopliae and B. bassiana significantly affected brood and adult honey bee survivorship and their immune responses. They were lethal to the bees with LC50s of 3.70 x 10(6) and 2.62 x 10()5 conidia/mL, respectively. The effect of temperature and thymol on conidia germination, production and colony growth of the fungal isolates was determined. Temperature significantly affected conidia germination, production and colony growth (P < 0.05) but thymol did not. Efficacy of the two most promising isolates (M. anisopliae UAMH 9198 and B. bassiana GHA) as potential bio-control agents against V. destructor in hives was evaluated. Fungal inocula were applied as dry formulation, with corn flour as carrier, using dispenser tray and dusting applications. Treatments were either applied alone or in combination with thymol to determine any synergistic effects. All treatments significantly increased mite mortality (P < 0.05), however, the mite control efficacy varied between fungal treatments and application methods. Combined treatments of fungi and thymol caused significantly higher mite mortality than single fungal treatments, which showed control levels of ≤61%. Significant differences in mite mortality were found between the two delivery methods with the differences depending on the fungal isolate. The results suggest that M. anisopliae UAMH 9198 would be a more effective bio-control agent for the management of V. destructor in honey bee colonies than the other isolates tested when dispensed continuously in hives using delivery methods such as a dispenser tray. However, future research is needed to improve delivery methods and investigate the effect of carriers used in the formulation on the efficacy of such entomopathogenic fungi. / Ontario Ministry of Agriculture and Food (OMAF), University of Guelph
283

Methylglyoxal in Manuka-Honig (Leptospermum scoparium): Bildung, Wirkung, Konsequenzen

Atrott, Julia 18 August 2014 (has links) (PDF)
Honig hat seit jeher eine große Bedeutung für den Menschen. In den letzten Jahren erlangte neuseeländischer Manuka-Honig eine zunehmende Bekanntheit und Bedeutung, was auf die antibakteriellen Eigenschaften zurückzuführen ist. Insbesondere ein medizinischer Einsatz bei der Behandlung von Wunden erscheint vielversprechend. Die Ursache für die hohen antibakteriellen Eigenschaften von Manuka-Honig kann auf eine Besonderheit in der Zusammensetzung zurückgeführt werden. So wurden von Mavric et al. (2008) bis zu 100-fach höhere Gehalte an Methylglyoxal (MGO) gegenüber anderen Honigsorten ermittelt, welche für die inhibierende Wirkung auf eine Vielzahl an Bakterien verantwortlich sind. Ziel dieser wissenschaftlichen Arbeit war die weitere Aufklärung und Charakterisierung des Ursprungs und der Bildung des in Manuka-Honig enthaltenen MGO. Es stellte sich die Frage, warum MGO einen natürlichen Honigbestandteil darstellt, inwieweit die Bildung auf einer enzymatischen oder mikrobiellen Grundlage basiert und ob sie durch weitere Honigparameter, wie z.B. freie Aminosäuren oder phenolische Verbindungen, beeinflusst wird. Bei der Lagerung frischer Manuka-Honige kommt es zu einem markanten Anstieg der MGO-Konzentration bis zum Erreichen eines Plateaus, an dem der Honig in Bezug auf den MGO-Gehalt als „ausgereift“ betrachtet werden kann. Eine weitere MGO-Nachbildung ist nicht zu induzieren, vielmehr kommt es zu beginnenden Abbaureaktionen. Direkter Precursor ist die Verbindung Dihydroxyaceton (DHA), die bei der Honigreifung zu MGO umgesetzt wird, was den erstmaligen Nachweis von DHA durch Adams et al. (2009) bestätigt. Zur Bestimmung von DHA in Honig konnte eine RP-HPLC-Methode basierend auf einer Vorsäulen-Derivatisierung mit OPD und UV-Detektion erfolgreich etabliert werden. Das dabei entstehende DHA-OPD-Derivat wurde eindeutig als 2-Hydroxymethylchinoxalin identifiziert, ein möglicher Reaktionsmechanismus wurde aufgezeigt. DHA und MGO wurden in frischen und kommerziellen Manuka-Honigen in vergleichsweise hohen Mengen bis zu 2700 mg/kg DHA bzw. 700 mg/kg MGO quantifiziert. Es ergibt sich für „ausgereifte“ Honige eine gute lineare Korrelation, die mit einem mittleren DHA-MGO-Verhältnis von 2:1 beschrieben werden kann. In frischen Proben liegen die Relationen signifikant höher, wodurch eine Einteilung der Honige nach „Reifegrad“ möglich ist. Honige anderer botanischer Herkunft weisen kein DHA und nur geringe Mengen MGO auf. Die Umsetzung von DHA zu MGO in der Honigmatrix wurde durch Dotierung von DHA-freien Honigsorten und anschließender Lagerung untersucht. Hierbei war eine Varianz in der MGO-Bildung feststellbar. Durch Einbeziehen weiterer Parameter wie z.B. pH-Wert, Wasser- oder Proteingehalt wurde deutlich, dass die DHA-Konzentration im Honig zwar den wesentlichen Faktor für den resultierenden MGO-Gehalt darstellt, die Umsetzung jedoch durch Unterschiede in der Honigmatrix beeinflusst wird. Eine Korrelation zu einzelnen Parametern kann nicht herausgestellt werden. Ergänzend zu den spezifischen Komponenten MGO und DHA wurde eine Bestimmung von weiteren Inhaltsstoffen von Manuka-Honig vorgenommen, um eine umfassende chemische Charakterisierung dieser Sorte zu ermöglichen und etwaige Auffälligkeiten in der Zusammensetzung von Manuka-Honig aufzuzeigen. Darüber hinaus wurden die Konzentration an 5 Hydroxymethylfurfural (HMF) und die Diastasezahl (DZ) als rechtlich geregelte Qualitätsparameter einbezogen. Die Anwendbarkeit dieser Faktoren für Manuka-Honig sowie die Folgen einer thermischen Behandlung wurden hierbei geprüft und diskutiert. Die zur Verfügung stehenden Manuka-Honige wurden hinsichtlich der Gehalte an Wasser, Fructose, Glucose, Proteinen, freier Aminosäuren, phenolischer Verbindungen sowie der Parameter pH-Wert und Honigfarbe analysiert. Dabei kann diese Sorte im Allgemeinen als hell- bis dunkelbrauner Honig beschrieben werden, der sich durch vergleichsweise hohe Mengen an Proteinen und freien Aminosäuren sowie einen hohen Gesamtphenolgehalt auszeichnet. Zudem konnte ein signifikant höherer Wassergehalt im Vergleich zu mitgeführten Honigen anderer botanischer Herkunft ermittelt werden. Frische Manuka-Honige zeichnen sich analog zu anderen frischgewonnenen Honigen durch einen sehr geringen Gehalt an HMF aus, der während der Lagerung stark ansteigen kann. In handelsüblichen Manuka-Honigen ergeben sich daher große Unterschiede in den bestimm-baren Konzentrationen. Anhand von Dotierungs- und Lagerexperimenten mit Kunsthonigmatrix und ausgewählten Honigen konnte ein Einfluss der freien Aminosäuren und des DHA auf die Bildung von HMF aufgezeigt werden. In der Folge kann von einer honigspezifischen Beeinflussung in Abhängigkeit von der Zusammensetzung ausgegangen werden. Im Vergleich zu anderen Honigsorten zeichnet sich Manuka-Honig durch eine eher niedrige bis mittlere DZ aus. Da frische, nachweislich unbehandelte Proben ebenfalls geringe Werte aufweisen können, ist dies nicht auf eine unsachgemäße Behandlung oder Erhitzung zurückzuführen. Neben der natürlichen Variation kann ein zusätzlicher Einfluss von DHA diskutiert werden. Dotierungsversuche lassen ein stärkeres Absinken der DZ bei der Lagerung unter Anwesenheit von DHA erkennen, dessen Ursache vermutlich in einer Hemmung des Enzyms durch eine Modifizierung relevanter Seitenketten begründet liegt. Untersuchungen an dem Honigenzym Invertase bestätigten diese These. Eine Behandlung von Honig mit hohen Temperaturen (70 °C) führte nachweislich zu keiner MGO-Bildung, wohingegen sowohl sensorische Beeinträchtigungen, als auch ein drastischer Anstieg an HMF zu verzeichnen waren. Spekulationen über das Erreichen einer „optimierten“ Bioaktivität durch eine aus rechtlicher Sicht unzulässige Erhitzung sind folglich nicht haltbar. Honig wird neben der antibakteriellen Wirkung mit weiteren biofunktionellen Eigenschaften in Verbindung gebracht. Darunter fallen z.B. ein antioxidatives und entzündungshemmendes Potential. Für Manuka-Honig kann eine potentielle Biofunktionalität auch auf die außergewöhnliche Präsenz von MGO zurückgeführt werden, das in der Literatur jedoch mit einer zytotoxischen Wirkung in Verbindung gebracht wird. Es erfolgte daher eine Bewertung der antimikrobiellen, antioxidativen sowie potentiell zytotoxischen Eigenschaften von Manuka-Honig unter Anwendung hierfür etablierter in vitro Testverfahren. Mittels Mikrodilutionstest wurden gegen vier klinisch relevante Bakterien (Escherichia coli, Staphylococcus aureus, Streptococcus pyrogenes und Pseudomonas aeruginosa) für MGO minimale Hemmkonzentrationen (MHK) zwischen 0,44 und 3,55 mM bestimmt, wobei die Inhibierung im Vergleich zu typischen Antibiotika geringer ist. Eine Antibiotika-Resistenz der Bakterien hatte keinen Einfluss auf die inhibierende Wirkung von MGO. In Anwesenheit von Zucker- bzw. Honigmatrix resultierten vergleichbare MHK-Werte für MGO. Geringe Unterschiede sind auf eine bessere Stabilität des MGO in Honigmatrix zurückzuführen, während etwaige synergistische Effekte durch weitere Komponenten nicht zu vermuten sind. Untersuchungen an ausgewählten Manuka-Honigen bestätigten MGO als maßgeblichen für die inhibierende Wirkung verantwortlichen Faktor. Des Weiteren wurde eine Korrelation zwischen MGO-Gehalt im Honig und antibakterieller Aktivität aufgezeigt. Zur Bestimmung der Zytotoxizität von Honig und 1,2-Dicarbonylverbindungen konnte der Koloniebildungstest als geeignetes Verfahren unter Nutzung einer einstündigen Inkubation der Zellen mit Proben in Phosphatpuffer etabliert werden. Für die verwendeten HT-29-Zellen wurde eine 50%ige Inhibierung für einen MGO-Gehalt von 0,7 mM ermittelt. Trotz hoher MGO-Gehalte zeigen Manuka-Honige im Mittel keine signifikant stärkere zytotoxische Wirkung als andere mitgeführten Nektar- und Honigtau-Proben. Die Werte lassen eine hohe Varianz innerhalb der Manuka-Honige erkennen, die nicht ausschließlich mit deren MGO-Konzentration in Verbindung gebracht werden kann. Die Beurteilung der antioxidativen Kapazität von Manuka-Honigen erfolgte mittels TEAC-II-Test, bezogen auf Trolox als Referenz. Im Vergleich zu anderen Sorten konnten signifikant höhere Werte ermittelt werden. Dabei ist ein direkter Zusammenhang zum Gesamtphenolgehalt festzustellen. Für Manuka-Honig lässt sich ein zusätzlicher Beitrag von MGO oder daraus entstehenden Folgeprodukten diskutieren. Prinzipiell ist die antioxidative Kapazität von Honig jedoch als sehr gering einzustufen.
284

The role of birds in the reproduction of an arid zone population of grey mistletoe, Amyema quandang (loranthaceae) / Nick Reid

Reid, Nick January 1984 (has links)
Bibliography: leaves [347]-361 / 361 leaves, [7] leaves of plates : ill ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Botany, 1985
285

Speaking the song, spreading the word, lifting the people : the reimagination of community through vocal music activism /

Smith, Arlette Miller. January 2005 (has links)
Thesis (Ph.D.)--State University of New York at Buffalo, 2005. / Includes bibliographical references. Also available on the Internet.
286

Avaliação da qualidade do mel e atividade da enzima invertase em Apis mellifera L. africanizadas

Arauco, Elvira Maria Romero [UNESP] 08 1900 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:58Z (GMT). No. of bitstreams: 0 Previous issue date: 2005-08Bitstream added on 2014-06-13T19:22:54Z : No. of bitstreams: 1 arauco_emr_dr_botfmvz.pdf: 810943 bytes, checksum: 6acc5913059689bd4615fef648271508 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / O néctar é coletado pelas operárias coletoras e transportado em sua vesícula nectarífera para a colméia. Durante a sua transformação em mel, o néctar recebe enzimas provenientes das glândulas hipofaringeanas, as quais atuam em seu processamento. A invertase é uma das enzimas adicionadas ao néctar e promove a inversão da sacarose em frutose e glicose. Com o objetivo de se conhecer o pH ideal dessa enzima nas abelhas operárias foram extraídas as glândulas hipofaringeanas de abelhas com oito dias de idade. O método utilizado para a dosagem da invertase foi o do ácido 3-5þ dinitrosalicílico (DNS) para determinação de açúcares redutores, utilizando-se medida de leitura espectrofotométrica em absorbância da glicose em comprimento de onda (?) igual a 540nm. De acordo com os resultados, verificou-se que a atividade catalítica da enzima foi mais eficiente no pH 5,0 e em 40 minutos de reação em comparação com outros valores de pH e tempos de reação. Não foi possível a reutilização das glândulas. Desta forma, concluiu-se que a enzima invertase aumentou sua eficiência em função do tempo de reação de forma linear e significativa em pH 5,0. / The nectar is collected by the collecting workers that carry it in its nectar gallbladder to the beehive. During its transformation in honey, the nectar receives enzymes proceeding from the hypopharyngeal glands, which act in its processing. Invertase is one of enzymes added to the nectar and promotes the inversion of sacarose in fructose and glucose. With the aim of knowing the ideal pH, in the worker bees, the bee's hypopharyngeal glands with eight days of age had been extracted. The used method, for the dosage of invertase, had been the 3-5 ' dinitrosalisilic acid for determination of reducing sugars, using absorbance spectrophotometry data from the glucose in ? equal to 540nm. According to the results, it had been verified that the enzyme catalytic activity had been more efficient in pH 5,0 and in 40 minutes of reaction, comparing to other pH values and times of reaction. The glands reuse had not been possible. At this way, it was concluded that the invertase enzyme had increased its efficiency by the reaction time at linear and significant way in pH 5,0.
287

Interação Formiga-Planta: As formigas diminuem os herbívoros presentes nas plantas de Qualea grandiflora no Cerrado / Ant-Plant Interaction: Do the ants decrease the herbivores present in Qualea grandiflora plants in the Cerrado

Maradini, Ana Carolina 26 February 2014 (has links)
Made available in DSpace on 2015-03-26T13:30:50Z (GMT). No. of bitstreams: 1 texto completo.pdf: 441528 bytes, checksum: 9be9f11077f57539e6290192246fd059 (MD5) Previous issue date: 2014-02-26 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Several species of plants in the Cerrado have extrafloral nectaries (EFNs), which produce secretions consumed by diverse species of ants. Ants foraging in plants and feeding on EFNs may act as important anti herbivore agents, decreasing phytophagous insects in the plants and the herbivory in the leaves. The aim of this study was to test if ants foraging on EFNs s plants decrease the number of herbivores in these plants. For this, was tested the hypothesis that the increase on the species richness and abundance of ants, cause a decrease in the herbivory, species richness and abundance of herbivores and proportion of guilds of herbivores. Sampling was performed in Panga Ecological Station, which lies between the cities of Uberlândia and Campo Florido, and possesses vegetation of several phytophysiognomies found in Cerrado biome. Plants of Qualea grandiflora were studied in three phytophysiognomies, Cerradão, Cerrado Strictu Senso and Campo Cerrado. According to the results, richness of ants did not influence in the decreasing of the herbivores and herbivory, however, it influenced the decrease of the proportion of chewing insects. In the other hand the abundance of ants promoted significant decrease of herbivores in Cerradão and Campo Cerrado, although in Cerrado Strictu Senso the relation has been opposite. The results also indicate that the abundance of sucking herbivores was higher in the Cerrado Strictu Senso regarding Cerradão and Campo Cerrado, indicating the possibility of interaction between the ants and the hemíptera that release honeydew. Futhermore the spatial and temporal differenciation between ants and herbivores in Cerrado Strictu Senso may also explain the result in this phytophysiognomy. The rate of herbivory in leaves did not suffer influence of the presence of ants possibly because the effect of foliar herbivory occurs only in long term and the sampling were made only in January, so that herbivory was underestimated compared to herbivores. The maturity of the leaves may also have influenced the response, because the younger leaves are more vulnerable to the action of herbivores than the more mature leaves. / Muitas plantas no Cerrado possuem nectários extraflorais (NEFs), os quais produzem um néctar que é consumido por muitas espécies de formigas. As formigas que forrageiam nas plantas e se alimentam dos nectários podem atuar como importantes agentes anti-herbívoros, diminuindo a presença dos insetos fitófagos e, consequentemente, a herbivoria nas folhas. O objetivo desse estudo foi testar se as formigas que forrageiam nas plantas que contém NEFs, causam diminuição dos herbívoros e sua atividade nelas. Para isso foram testadas as hipóteses de que o aumento da riqueza e abundância de formigas causa um decréscimo na herbivoria, bem como na riqueza e abundância de herbívoros, e também na proporção de guildas de herbívoros. A coleta foi realizada na Estação Ecológica do Panga, que se situa entre as cidades de Uberlândia e Campo Florido, e possui vegetações dentro de várias fitofisionomias encontradas nos Cerrados. Foram utilizadas plantas da espécie Qualea grandiflora nesse estudo, marcadas em três fitofisionomias: Cerradão, Cerrado Strictu Senso e Campo Cerrado para a realização das coletas. De acordo com os resultados obtidos, a riqueza de formigas não influenciou na diminuição dos herbívoros e da herbivoria, entretanto, influenciou na diminuição da proporção de insetos mastigadores nas plantas. Por outro lado, a abundância de formigas acarretou um decréscimo na abundância de herbívoros no Cerradão e Campo Cerrado, embora no Cerrado Strictu Senso, a relação tenha sido inversa. Os resultados indicam também que a abundância de herbívoros sugadores foi maior no Cerrado Strictu Senso em relação ao Cerradão e Campo Cerrado, indicando a possibilidade de interação entre as formigas e homópteras que liberam honeydew nessa fitofisionomia. Além disso, a diferenciação temporal e espacial das formigas e herbívoros no Cerrado Strictu Senso também pode explicar o resultado observado nessa fitofisionomia. A taxa de herbivoria nas folhas das plantas não sofreu influências da presença de formigas nas três fitofisionomias, possivelmente porque o efeito da herbivoria foliar ocorre somente em longo prazo e as coletas foram realizadas apenas durante o mês de janeiro, de forma que a herbivoria foi subestimada em relação aos herbívoros. A maturidade das folhas também pode ter influenciado na resposta, visto que folhas mais jovens são mais vulneráveis à ação dos herbívoros do que as folhas mais maduras.
288

Ovarian Regulation of Honey Bee (Apis mellifera) Foraging Division of Labor

January 2011 (has links)
abstract: There is increasing evidence that ovarian status influcences behavioral phenotype in workers of the honey bee Apis mellifera. Honey bee workers demonstrate a complex division of labor. Young workers perform in-hive tasks (e.g. brood care), while older bees perform outside tasks (e.g. foraging for food). This age correlated division of labor is known as temporal polyethism. Foragers demonstrate further division of labor with some bees biasing collection towards protein (pollen) and others towards carbohydrates (nectar). The Reproductive Ground-plan Hypothesis proposes that the ovary plays a regulatory role in foraging division of labor. European honey bee workers that have been selectively bred to store larger amounts of pollen (High strain) also have a higher number of ovarioles per ovary than workers from strains bred to store less pollen (Low strain). High strain bees also initiate foraging earlier than Low strain bees. The relationship between ovariole number and foraging behavior is also observed in wild-type Apis mellifera and Apis cerana: pollen-biased foragers have more ovarioles than nectar-biased foragers. In my first study, I investigated the pre-foraging behavioral patterns of the High and Low strain bees. I found that High strain bees progress through the temporal polyethism at a faster rate than Low strain bees. To ensure that the observed relationship between the ovary and foraging bias is not due to associated separate genes for ovary size and foraging behavior, I investigated foraging behavior of African-European backcross bees. The backcross breeding program was designed to break potential gene associations. The results from this study demonstrated the relationship between the ovary and foraging behavior, supporting the proposed causal linkage between reproductive development and behavioral phenotype. The final study was designed to elucidate a regulatory mechanism that links ovariole number with sucrose sensitivity, and loading decisions. I measured ovariole number, sucrose sensitivity and sucrose solution load size using a rate-controlled sucrose delivery system. I found an interaction effect between ovariole number and sucrose sensitivity for sucrose solution load size. This suggests that the ovary impacts carbohydrate collection through modulation of sucrose sensitivity. Because nectar and pollen collection are not independent, this would also impact protein collection. / Dissertation/Thesis / Ph.D. Biology 2011
289

Monitoramento do desenvolvimento de colônias de Abelhas africanizadas sobre a influência do sol e sombra na região semiárida do nordeste brasileiro (Mossoró -RN) / Monitoring of the development of colonies of africanized honey bees under the influence of sunligth and shade in the semiarid region of northeast of Brazil (Mossoró-RN)

Sombra, Daiana da Silva 28 August 2013 (has links)
Made available in DSpace on 2016-08-15T20:31:09Z (GMT). No. of bitstreams: 1 DaianaSS_DISSERT.pdf: 992609 bytes, checksum: 09ead14cb109f1d0241dab4527cc9c70 (MD5) Previous issue date: 2013-08-28 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This study aimed to assess the the effect of direct sunlight and shade in two groups of AHB colonies. Sheets of carnauba trees were used to provide shading for a group of hives and as control another group of hives were installed direct under the sun. The experiment was conducted at the Technology Center of Beekeeping and Meliponiculture of Rio Grande do Norte, at the Experimental Station of UFERSA, Mossoró-RN. 16 Langstroth beehives were used, 8 in the shade and 8 under the sun. During the period from April, 05, 2012 to March 18, 2013 were performed monthly monitoring and about the development of the colonies. Approximatelly every 10 days the survey was conducted with data collected in % in the areas of oviposition (eggs laying by queens) ,open brood, capped brood, honey and pollen. The data were tested for normality, analysis of variance based on the least squares method and the comparison of means was done by Tukey test with 5% level of significance The environment showed an influence upon duration or longevity of colonies with difference statistically significant (P <0.01), with an average duration of 132 days in the sun and 155 days in the shade. During the experiment, the colonies had 65% reduction in bee populations in the shade and 90% under the sun. There were no statistical differences between the groups as oviposition, open brood and capped brood. The area of honey was higher in the colonies under the sun and pollen area was higher in shadow environment, both differences statistically significant (P<0,01). The drought of 2012, the most serious in the last 50 years in the Brazilian Northeast, had an important impact on both groups of colonies but the AHB colonies had a better adaptation in the shadow than under the sun in the semiarid Northeast region. Honey production accumulated in the colonies supers installed in the shade was approximately 45% higher than under the sun. It was found that bees (AHB) have a better adaptation to the environment under the shadow of the sun in the semiarid Northeast / Este estudo objetivou avaliar o efeito da ação direta do sol e da sombra em colônias de abelhas africanizadas (AHB). Foram utilizadas coberturas naturais com folhas de carnaúba para o sombreamento das colmeias, tendo como controle colmeias instaladas ao sol. O experimento foi realizado na Fazenda Experimental da UFERSA, (CETAPIS) em Mossoró-RN. Foram utilizadas 16 colmeias modelo Langstroth com abelhas AHB, 8 na sombra e 8 sob o sol. Durante o período de 05/04/2012 a 18/03/2013, foram realizados monitoramento mensais para avaliar o desenvolvimento das colônias e a cada 10 dias o levantamento das áreas de oviposição, cria aberta, cria operculada, mel e pólen. Foi testada a normalidade dos dados, aplicada análise de variância (método quadrados mínimos) e comparação das médias pelo Teste de Tukey com nível de 5% de significância. O ambiente exerceu influência sobre a duração das colônias (P<0.01) com média de 132 dias no sol e 155 dias à sombra. Durante o experimento as colônias tiveram 65% de redução nas populações de abelhas à sombra e 90% sob o sol. Não foram encontradas diferenças estatísticas entre os ambientes quanto a oviposição das rainhas, cria aberta e cria operculada. A área de mel foi superior no sol e a área de pólen foi superior na sombra. A seca de 2012, uma das mais sérias nos últimos 50 anos no nordeste brasileiro, teve impacto em ambos os grupos. A produção de mel acumulado ao longo do experimento nas melgueiras das colônias à sombra foi aproximadamente 45% superior às colônias submetidas ao sol. Constatou-se que as abelhas africanizadas apresentam melhor adaptação ao ambiente sombra do que sob o sol no semiárido Nordestino
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Qualidade de mel de abelha Apis mellifera l natural e após utilizado para alimentação de abelhas Melipona subnitida

Tôrres, Wedson de Lima 11 November 2017 (has links)
Submitted by Vanessa Christiane (referencia@ufersa.edu.br) on 2018-03-27T20:27:33Z No. of bitstreams: 1 WedsonLT_DISSERT.pdf: 1073579 bytes, checksum: 409886291a5814c831107fd57eaf6b1e (MD5) / Approved for entry into archive by Vanessa Christiane (referencia@ufersa.edu.br) on 2018-06-18T16:58:13Z (GMT) No. of bitstreams: 1 WedsonLT_DISSERT.pdf: 1073579 bytes, checksum: 409886291a5814c831107fd57eaf6b1e (MD5) / Approved for entry into archive by Vanessa Christiane (referencia@ufersa.edu.br) on 2018-06-18T16:58:35Z (GMT) No. of bitstreams: 1 WedsonLT_DISSERT.pdf: 1073579 bytes, checksum: 409886291a5814c831107fd57eaf6b1e (MD5) / Made available in DSpace on 2018-06-18T16:58:51Z (GMT). No. of bitstreams: 1 WedsonLT_DISSERT.pdf: 1073579 bytes, checksum: 409886291a5814c831107fd57eaf6b1e (MD5) Previous issue date: 2017-11-11 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The physicochemical analysis reveals the quality of honeys comparing with standards already established by the Brazilian regulation law. This work aims evaluate the quality mellifera L. honey, collected in regulated and unregulated honey establishments at Sertão do Apodi territory -RN, Northeastern of Brazil, and reevaluate this quality after used as feed for stingless bees Melipona subnitida. The changes made by this stingless bees in the Apis honey was descripted. The honey samples were collected in 2016 and 2017at 22 honey establishments. All the samples were transported to the UFERSA Food Technology Laboratory where the following quality characteristics were evaluated: moisture, pH, free acidity (LA), electrical conductivity (EC), hydroxymethylfurfural (HMF), reducing sugars (SFA), ash content, color, water activity (AW), total phenolics (FT), total flavonoids (FT) and antioxidant activity. The experimental design was randomized The physicochemical composition of Apis mellifera honeys, differ between registered and unregistered honey establishments The Apis honey was modified by the stingless bees on to the following physicochemical parameters: moisture, reducing sugars, ash, insoluble solids, acidity and pH. However, the final characteristics of the modified honey were closer to the honeybees honey.. Unexpectedly, the total phenolic content, flavonoids and antioxidant activity of the modified honey were higher than the natural Melipona honey / As análises físico-químicas revelam a qualidade de méis e compara com os padrões já estabelecidos na legislação. Por ocasião do período de escassez a alimentação artificial para meliponineos é uma técnica fundamental para a manutenção das colmeias em determinadas épocas do ano, Nesse sentido, o presente trabalho teve por objetivo avaliar a qualidade de mel de abelha Apis mellifera L. coletado em casas de méis do território Sertão do Apodi-RN e, após utilizado como alimentação para abelhas Melipona subnitida. O trabalho foi realizado em duas etapas, a primeira consistiu de coletas de mel de Apis mellifera, nos anos de 2016 e 2017 em uma casa certificada de mel e em 22 casas de méis sem certificação no território sertão do Apodi. A segunda etapa consistiu em selecionar seis colônias de Melipona subnitida para alimentação das abelhas com o mel homogeneizado de Apis, resultante da primeira etapa de coleta, e procedeu-se à colheita para análise das mudanças físico-químicas efetuadas pelas abelhas jandaíras. Em todas as etapas, as amostras foram transportadas para o laboratório de Tecnologia de Alimentos da UFERSA onde foram avaliadas as seguintes características de qualidade: umidade, pH, acidez livre (AL), condutividade elétrica (CE), hidroximetilfurfural (HMF), açúcares redutores (AR), sacarose aparente (SAC), sólidos insolúveis (SI), teor de cinzas, cor, atividade de água (AW), fenólicos totais (FT),flavonoides totais (FT) e atividade antioxidante. O delineamento experimental utilizado foi em blocos casualizado. A composição físico-química de amostras de méis de Apis mellifera coletadas nas casas de méis (UEPA) do território sertão do Apodi, diferiram quanto o teor de umidade, cinzas, acidez livre e sacarose. A abelha Melipona subnitida modificou os seguintes padrões físico-químicos do mel de Apis: umidade, açúcares redutores, cinzas, sólidos insolúveis, acidez e pH. Porém, as características finais do mel modificado ficaram mais próximas do mel de Apis mellifera. O conteúdo de fenólicos totais, flavonóides e atividade antioxidante do mel modificado foram superiores ao mel de abelha jandaíra natural / 2018-03-27

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