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ABSTRACT MORPHOMETRIC, MtDNA AND MICROSATELLITE ANALYSIS IN HONEYBEE POPULATIONS (Apis mellifera L.) OF NORTH AND NORTHWEST IRAN Morphometric measurements, mitochondrial DNA analyses and 5 microsatellite loci were used to investigate variation in the honeybee populations of Iran and comparing it with the Turkish populations. Five honeybee populations were sampled from North and west north of Iran. In morphometric aspect of the study 23 characters were measured from left forewings and hindlegs of honey bee samples. The data were analysed by multivariate statistical analyses. By using mtDNA analyses length polymorphism of the intergenic region COI-COII of mitochondrial DNA was studied. After amplification of this region by the polymerase chain reaction, DraI enzyme was used for restriction of amplified region. Results of mtDNA studies show no diversity between four populations and all of them exhibit the same C1 pattern. Five microsatellite loci (A7, A24, A28, A43 and A113) were used in this studies.A high level of average heterozygosity changing between 0.611 and 0.709 was detected in Iranian honey bee populations, and a significant degree of polymorphism was observed. Although Urmia, Sarein and Viladereg populations are similar, Amol population which has located in northern Iran shows a significant difference from other populations. Result obtained form morphometric studies are supporting microsatellite analyses. By comparing data obtained form Iranian honey bee populations with Turkish population (Hakkari), western populations (Urmia, Sarein and Viladereg) are more similar to Hakkari population. It is found Amol is significantly different form other populations and better represents Iranian honeybee.

We analyzed the genetic structures of 11 honeybee (Apis mellifera) populations from T&uuml / rkiye and one population from Cyprus using 9 microsatellite loci. Average gene diversity levels were found to change between 0,542 and 0,681. Heterozygosity levels, mean number of alleles per population, presence of diagnostic alleles and pairwise FST values confirmed the mitochondrial DNA finding that Anatolian honeybees belong to north Mediterranean (C) lineage. We detected a very high level of genetic divergence among populations of T&uuml / rkiye and Cyprus based on pairwise FST levels (between 0,0 and 0,2). Out of 66 population pairs 52 were found to be genetically different significantly. This level of significant differentiation has not been reported yet in any other study conducted on European and African honeybee populations. High allelic ranges, and high divergence indicate that Anatolia is a genetic centre for C lineage honeybees. We suggest that certain precautions should be taken to limit or forbid introduction and trade of Italian and Carniolan honeybees to T&uuml / rkiye and Cyprus in order to preserve genetic resources formed in these territories in thousands of years. Effectivity at previously isolated regions in Artvin, Ardahan and Kirklareli was confirmed by the high genetic differentiation in honeybees of these regions. Genetically differentiated Karaburun and Cyprus honeybees v and geographical positions of the regions make these zones first candidates as new isolation areas.

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniversitet, 2006. / Härtill 4 uppsatser.

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniversitet, 2009. / Härtill 4 uppsatser.

Made available in DSpace on 2014-06-11T19:35:43Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-08-23Bitstream added on 2014-06-13T21:07:59Z : No. of bitstreams: 1 pereira_am_dr_rcla.pdf: 830341 bytes, checksum: de8af8468e88b6f5c5cf902007f24ed7 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / As abelhas Apis mellifera são insetos ecologicamente e economicamente importantes. Elas asseguram a polinização de diversas plantas contribuindo para a manutenção da biodiversidade. Seu valor econômico resulta não somente de seus produtos diretos mas também pela ativa polinização que exercem em culturas. A polinização feita por animais é importante para a reprodução sexuada de muitas culturas e para a maioria das plantas nativas, as quais também podem ser importantes como fonte de calorias e micronutrientes para os seres humanos. Além do mais, o declínio no número de polinizadores pode acarretar uma redução concomitante no número de espécies vegetais. A abelha A. mellifera, destaca-se como polinizador economicamente mais valioso para culturas em todo o mundo. Por outro lado, a agricultura moderna cada vez mais depende do uso de produtos químicos para controlar plantas daninhas, fungos e insetos-praga para assegurar a produtividade. Abelhas melíferas podem entrar em contato com tais agentes químicos devido suas atividades de coleta de água, resinas vegetais, pólen e néctar. A intoxicação resultante desta exposição pode ser letal, o que é facilmente identificável, ou causar efeitos na fisiologia e no comportamento do inseto. Tais efeitos, ocasionados por doses subletais, são difíceis de serem mensurados, como paralisia, desorientação ou mudanças comportamentais; porém, podem comprometer toda a estrutura social da colônia. Visando um melhor conhecimento dos efeitos de doses subletais de inseticidas em abelhas, estudou-se a ação dos ingredientes ativos Acetamiprido, Tiametoxam e Fipronil na sobrevivência e nos comportamentos de reflexo de extensão da probóscide e da atividade locomotora em operárias de A. mellifera. Preliminarmente, observou-se a DL50 vinte e quatro horas após o tratamento tópico do Acetamiprido Tiametoxam e Fipronil foram registrados... / the pollination of many wild flowers, and thus contributing to plant biodiversity. Their economic value derives not only from their direct products but also from their pollinating activity in crop plants. Animal pollination is important to sexual reproduction of many crops and the majority of wild plants, which can also be important for providing calories and micronutrients for humans. Furthermore, the decline of pollinating species can lead to a parallel decline in number of plant species. A. mellifera stands out as the most economically valuable crop pollinator in the world. Modern agriculture increasingly depends on the use of chemicals substances to control weeds, fungi and insect pests to ensure high yields. Honey bees may frequently become exposed to such chemicals as a consequence of their foraging activities collecting water, natural resins, pollen and nectar. Intoxication resulting from this exposure can be lethal, which is easily identifiable, or cause effects on the physiology and insect behavior. These effects, caused by sublethal doses are difficult to measure (such as paralysis, disorientation or behavioral changes), and can compromise the entire social structure of the colony. To improve the knowledge about the effects of insecticides sublethal doses effects in honey bees, we studied the action of the active ingredients Acetamiprid, Thiamethoxam and Fipronil on survival and behavior of the proboscis extension reflex (PER) and locomotor activity in workers of A. mellifera. Twenty-four hours after topic application, the LD50 values of Acetamiprid, Thiamethoxam and Fipronil were 9,3 μg/bee, 17 ng/bee and 1,9 ng/bee, respectively. We also estimated a LT50 with values of 1,4 hours, 3,8 hours and 19,8 hours to Acetamiprid, Thiamethoxam and Fipronil respectively. The behaviors were analyzed 1, 4 and 24 hours after topical application of active ingredients at doses corresponding... (Complete abstract click electronic access below)

Varroa destructor, principal ectoparasite de l'abeille, est l'un des responsables majeurs des phénomènes de perte de colonies observés partout dans le monde. Depuis son changement d'hôte et l'infestation de colonies d'Apis mellifera dans les années 1970, des traitements essentiellement chimiques ont été proposés pour limiter l'infestation. Pourtant ces dernières années, ces traitements ont fait l'objet d'études critiques à la fois à cause de la résistance émergente du parasite aux différents acaricides et du fait de la sensibilité des abeilles à l'accumulation de produits chimiques dans les différentes matrices de la ruche. De nouveaux traitements alternatifs contre la varroose sont donc nécessaires et très attendus afin d'enrayer rapidement les effets délétères du parasitisme acarien. Cependant, la recherche de ces nouvelles cibles thérapeutiques est limitée par l'absence d'un système d'élevage synchronisé de l'hôte et de son parasite en laboratoire. L'objectif technique de ce travail de thèse était donc de pallier à ce manque en développant une méthode pour coupler l'élevage de larves d'abeilles in vitro avec le transfert à la fois de la phase phorétique et de la phase de reproduction du parasite (respectivement sur les adultes et sur les pupes) dans des conditions de laboratoire. Le système mis au point lors de ces travaux de thèse a permis une étude plus approfondie de l'impact de facteurs variables chez l'hôte sur plusieurs points clés du cycle parasitaire. Les effets de la nutrition larvaire chez l'abeille, la longueur de la phase phorétique, le type d'abeilles adultes sur lequel Varroa reste au cours de cette phase ou encore l'âge des stades larvaires ont ainsi été étudiés. L'analyse des impacts potentiels de ces facteurs a porté principalement sur certains paramètres de la reproduction, du comportement et de la virulence de V. destructor. Les résultats obtenus ont montré que la nutrition larvaire, ou plus précisément la supplémentation de la nourriture larvaire avec des pollens monofloraux et polyfloraux, a un faible impact sur la reproduction du parasite, mais présente une tendance à influencer le poids de l'abeille ainsi qu'à potentiellement augmenter la tolérance de l'abeille à certains des symptômes de la varroose, tels que la perte de poids. La reproduction du parasite n'a pas non plus été affectée par les variations induites dans la phase phorétique. Ni la fertilité du parasite, ni l'expression des deux gènes de la vitellogénine n'ont fluctué lorsque la durée ou l'âge des adultes parasités pendant la phase phorétique variaient. En revanche, la durée du séjour sur les abeilles adultes avant la reproduction est corrélée positivement à la charge virale chez le parasite, ce qui explique pourquoi les varroas ayant vécu une longue phase phorétique induisent plus fréquemment des malformations. Enfin, l'âge des stades juvéniles des abeilles sont tous attrayants pour Varroa destructor, bien que certaines préférences aient été mises en évidence dans notre étude. Si l'attraction pour le 5ème stade larvaire et les abeilles nouvellement écloses est déjà connu, l'attractivité des nymphes aux yeux blancs est un phénomène nouveau qui pourrait être d'importance majeure pour la compréhension du cycle parasitaire. Des analyses approfondies pour isoler les signaux responsables de cette attraction restent nécessaires. En conclusion, les travaux de cette thèse offrent une méthode d'élevage innovante et ouvrent ainsi, pour l'ensemble de la communauté apicole, de nouvelles avenues de recherche passionnantes afin de développer nos connaissances à la fois sur l'abeille, sur le parasite et sur les virus qu'il transporte. Ce travail pourrait permettre d'identifier de nouvelles cibles thérapeutiques pour la conception de traitements alternatifs ciblant spécifiquement le parasite sans nuire à l'abeille. / Varroa destructor is the principal acarian parasite of the honey bee, involved in the phenomenon of colony loss which has been reported worldwide. Since its host shift from Apis cerana to Apis mellifera in the 1970's, chemical treatments have been set up to limit infestation. For many years however, these treatments have been the subject of critical studies both because of the resistance of the parasite to acaricides and of the sensitivity of bees to chemical accumulation in hive matrices. New alternative ways of varroatosis treatment are therefore urgently needed to limit the deleterious effects of the acarian parasitism. However, the search for these alternative therapeutic targets is limited by the lack of a laboratory system to transfer and synchronize the cycles of V. destructor and the honey bee under controlled conditions. The methodological objective of this Phd work was to overcome this issue by developing a method to couple the rearing of honey bee larvae in vitro to the transfer of both the parasite phoretic and reproductive phases (respectively on adults and on pupae) in laboratory conditions. Our system allowed further investigation regarding the impact of variable parameters in the host on several key points of the parasite cycle. The effects of several factors -such as the bee larval nutrition, the length of the phoretic phase, the type of adult bees on which Varroa stays during this phase or the age of pupal development- were studied. The potential impact in the parasite cycle focused mainly on reproductive, behavioural and virulence related parameters. The results obtained from our experiments showed that larval nutrition, tested via the supplementation of the larval food with pollen, had no impact on the reproduction of the parasite but a tendency to influence the weight of the bee, potentially increasing the bee tolerance to some of the symptoms of varroatosis, such as the weight loss. The reproduction of Varroa was not impacted by variations induced in the phoretic phase either. Neither the fertility of the parasite nor the expression of its two vitellogenin genes were impacted by the duration or the age of adults parasitized during the phoretic phase. On the other hand, the length of the stay on adult bees before reproduction positively correlates with the viral loads in the parasite, which explains why varroas experiencing a long phoretic phase induce malformation more frequently in parasitized pupae. Finally, the age of juvenile stages of the honey bees are all attractive to Varroa destructor, although some preferences have been highlighted in our study. If the attraction for 5th instar larvae and newly emerged bees have already been described, the attractions towards the white eyed pupae is a new phenomenon that could be of major importance in the understanding of the parasite cycle. Further analysis to isolate and shed light on the attraction signals involved in the process is needed. Altogether, this thesis has supplied, for the whole scientific beekeeping community, new exciting research avenues and methodologies to develop our knowledge about the bee, the parasite and the viruses it carries. It might allow us, in the future, to design alternative treatment specifically targeting the parasite without injuring the honey bee.

Telomeres are nucleoprotein structures at the ends of eukaryotic chromosomes that are important for genome stability and integrity. They are shortened with each cell cycle and during organismal aging. Although the most common telomere length compensation mechanism is the activity of a special reverse transcriptase, telomerase, in Drosophila telomeres are maintained by the retrotransposition of telomeric elements. In mammals, telomere length and telomerase activity can be influenced by lifestyle and the environmental conditions. This thesis is focused on activity of telomere length maintenance mechanism in insects in relation to aging and stress response.

Submitted by Reginaldo Soares de Freitas (reginaldo.freitas@ufv.br) on 2017-04-03T12:10:51Z No. of bitstreams: 1 texto completo.pdf: 184090 bytes, checksum: a69f65d2e1070c11a8dcc96ded76aca7 (MD5) / Made available in DSpace on 2017-04-03T12:10:51Z (GMT). No. of bitstreams: 1 texto completo.pdf: 184090 bytes, checksum: a69f65d2e1070c11a8dcc96ded76aca7 (MD5) Previous issue date: 2004-02-11 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / O objetivo deste trabalho foi estudar os efeitos do aumento na abundância de Apis mellifera, espécie exótica, sobre a coleta de pólen por Melipona quadrifasciata, espécie nativa, em Viçosa, MG. Para isso, foi estudado o padrão diário de atividade de coleta de pólen por M. quadrifasciata em áreas de pastagem abandonada e em áreas de fragmentos de mata secundária, com a finalidade de testar a hipótese de que a abundância aumentada de A. mellifera causa alterações neste padrão. Também foram identificadas as espécies de plantas que são fontes de pólen para ambas as espécies nas mesmas áreas, a fim de testar a hipótese de que a abundância aumentada de A. mellifera causa alterações na quantidade e na qualidade do pólen coletado por M. quadrifasciata. A atividade de coleta de pólen por M. quadrifasciata se iniciava ainda durante o nascer do sol e se concentrava nas primeiras horas da manhã. Cerca de 69.40% de todas as cargas de pólen foram coletadas até as 10 horas da manhã. A abundância aumentada de A. mellifera não causou alterações sobre o padrão diário de coleta de pólen por M. quadrifasciata. Para a coleta de pólen, M. quadrifasciata visitou, nas áreas de pastagem abandonada, 23 espécies de plantas pertencentes a 9 famílias de Angiospermae e, nos fragmentos de mata, foram coletadas cargas de pólen de 20 espécies pertencentes a 10 famílias. M. quadrifasciata visitou, para a coleta de pólen, principalmente plantas de porte arbóreo, com floração massal, e flores que oferecem o pólen como recurso. Embora seja generalista, M. quadrifasciata é mais restritiva que outras abelhas eussociais para a coleta de pólen e apresenta uma oligolecia temporal. As abelhas dos ninhos de A. mellifera instalados nas áreas de pastagem visitaram 25 espécies de plantas, pertencentes a 16 famílias. Nos ninhos instalados na mata, foram encontradas 33 espécies pertencentes a 21 famílias. A. mellifera também é generalista e utilizou plantas com floradas abundantes, embora não tenha utilizado apenas plantas de porte arbóreo para a coleta de pólen. Embora houvesse uma sobreposição de nicho relativamente alta, a abundância aumentada de A. mellifera não apresentou efeitos sobre a largura de nicho e sobre a quantidade e a qualidade do pólen coletado por M. quadrifasciata. A não detecção de efeitos da abundância aumentada de A. mellifera pode acontecer em decorrência do fato de que pólen não é um fator limitante ou do fato de que o sistema já está estável, moldado à presença de A. mellifera. É possível, também, que a não detecção de efeitos seja decorrente do número de colônias de A. mellifera utilizadas em cada experimento não ser suficiente para significativamente aumentar a abundância nas áreas estudadas, embora seja útil para se medir efeitos da introdução de ninhos de abelhas africanizadas para a produção apícola. Embora os dados desse trabalho apontem para uma ausência de efeitos sobre as abelhas eussociais, a presença da A. mellifera nas regiões Neotropicais ainda tem muitos aspectos a serem estudados. / This work’s goal is to study the effects of the increased abundance of Apis mellifera, an exotic species, in the pollen collection of Melipona quadrifasciata, a native species. In order to do this the daily pattern of pollen collection by M. quadrifasciata was studied, to test the hypothesis that the increased abundance of A. mellifera resulted in changes in this pattern. The plant species used as pollen sources by both species were also studied, to test the hypothesis that the increased abundance of A. mellifera resulted in quantitative and qualitative changes in pollen collection by M. quadrifasciata. Pollen collection by M. quadrifasciata began during sunrise and was concentrated in the first hours of the morning. About 69.40% of all the pollen loads were collected until 10 o’clock in the morning. The increased abundance of A. mellifera didn’t change the daily pattern of pollen collection by M. quadrifasciata. Twenty-three plant species belonging to 9 families of Angiosperms were visited by M. quadrifasciata for pollen collection in the abandoned grazing areas while in the areas of forest fragments, it visited 20 plant species from 10 families. M. quadrifasciata used mainly trees with mass flowering as pollen sources and flowers that offer pollen as reward. Though it is generalist, M. quadrifasciata is more restrictive than other eusocial bees and shows a temporal oligolecy. The bees from the A. mellifera nests visited 25 plants species from 16 families in the grazing abandoned areas and 33 plant species from 21 families in the areas of forest fragments. A. mellifera is also a generalist and used plants with abundant flowering, though it didn’t used only trees. Even though there was a relatively high niche overlap, the increased abundance of A. mellifera didn’t change M. quadrifasciata’s niche breadth and the quality or quantity of pollen collected. Not detecting effects of the increased abundance of can happen due to the fact that pollen is not a limiting factor or that the system is stable, adapted to the presence of A. mellifera. Or maybe it is due to the fact that the number of colonies of A. mellifera used wasn’t high enough to significantly increase its abundance; it is useful, however, to measure the effects of introduction of africanized honey bee nests for beekeeping. Even though data from this work show that there are no effects on eusocial bees, the presence of A. mellifera in the Neotropics still has many aspects to be studied. / Não foi localizado o cpf do autor.

Submitted by Reginaldo Soares de Freitas (reginaldo.freitas@ufv.br) on 2016-08-19T13:00:22Z No. of bitstreams: 1 texto completo.pdf: 1010449 bytes, checksum: 683cc192728b7da70834ca8fcdd27ea5 (MD5) / Made available in DSpace on 2016-08-19T13:00:22Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1010449 bytes, checksum: 683cc192728b7da70834ca8fcdd27ea5 (MD5) Previous issue date: 2016-03-04 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Em abelhas eussociais, que inclui Apis mellifera, a colônia é constituída por uma rainha, com função reprodutiva, e de operárias estéreis ou semi-estéreis, que exercem as demais funções dentro da colônia como cuidados com a prole e busca por alimento. Associada ao aparelho do ferrão há a glândula de Dufour, que dentre outras funções, desempenha importante papel na comunicação entre os membros da colônia. Esta glândula libera substâncias químicas, mas a natureza e a função dos compostos variam em diferentes táxons. O objetivo deste estudo foi identificar proteínas com abundância diferencial nas glândulas de Dufour de operárias nutridoras e campeiras de A. mellifera. As glândulas de Dufour foram dissecadas, e as proteínas, extraídas. Os extratos proteicos foram submetidos à eletroforese bidimensional em gel. Spots diferencialmente abundantes foram digeridos e os peptídeos analisados no espectrômetro de massas MALDI/TOF- TOF. Os espectros de fragmentação (MS/MS) foram pesquisados em bancos de dados usando a ferramenta Mascot, e as proteínas identificadas foram validadas usando o software Scaffold. Um total de 131 spots apresentou abundância diferencial entre nutridoras e campeiras, sendo identificadas 28 proteínas distintas. Destas 28 proteínas identificadas, 21 foram mais abundantes em nutridoras e sete proteínas foram mais abundantes em campeiras. As proteínas identificadas pertencem a diferentes categorias funcionais envolvidas nos metabolismos proteico, energético, lipídico e de carboidratos, detoxificação, homeostase, comunicação celular, citoesqueleto, proteínas constitutivas e alergênicas. Os dados obtidos neste estudo trazem novas informações que contribuem para a compreensão das funções biológicas da glândula de Dufour e seu papel na organização social das abelhas. / The colony of the eusocial bee Apis mellifera has a reproductive queen and sterile workers that make many tasks as brood care and foraging. The chemical communication has a crucial role for the maintenance of sociability in bees and many compounds are released by exocrine glands. The Dufour’s gland is a non-paired gland associated with the sting apparatus with important function in the communication between members of the colony. This gland release chemicals, but the nature and function of the compounds varies in workers playing different tasks. The objective of this study was to identify differentially expressed proteins in the Dufour’s glands in forager and nurse workers of A. mellifera. The Dufour’s glands of both honeybee workers were dissected and proteins were extracted. The protein content was submitted to 2D-gel electrophoresis, differentially expressed spots were digested and peptides analyzed in MALDI TOF- TOF mass spectrometer. Fragmentation spectra (MS/MS) were searched in databases by using the Mascot algorithm and proteins identified were validated through Scaffold software. A total of 131 spots showed different expression between forager and nurse bees, and 28 proteins were identified. Among them, 21 proteins were upregulated in nurses and 7 ones in foragers bees. The identified proteins have different functions as protein, energy, lipid and carbohydrate metabolism, detoxification, homeostasis, cell communication, cytoskeleton, constitutive proteins and allergen. This study provides new insights contributing to the comprehension of the biological functions of the Dufour’s gland in honey bees.