Phosphoglucomutase (PGM) is one of the central enzymes in energy metabolism at a branch point at the head of the metabolic pathway leading into glycogen metabolism, pentose shunt and the main glycolytic cycle, catalyzing the reversible interconversion of glucose-1-phosphate to glucose-6-phosphate. Whole year, month to month analysis of pattern of allozyme variation at Pgm and Hk loci in Apis mellifera L. from three provinces / Kirklareli, Artvin, and Hatay revealed that there is significant seasonal variation of allozyme frequencies at Pgm locus (P&lt / 0.001). The difference in genotype frequencies between summer and winter samples is apparent in Pgm, whereas at Hk locus, which is analyzed as a control there is seasonal variation in genotype frequencies. Biochemical measurements of the enzyme activities and glycogen content of different Pgm genotypes were performed to determine the effect of different Pgm genotypes on the physiological performance of the honeybees and it was observed that both enzyme activity and glycogen amount is higher in heterozygote individuals which are in high frequency during winter months (P&lt / 0.0001). Furthermore, PGM enzyme activity and glycogen content was found to be significantly correlated. These findings clearly demonstrate that biochemical differences between different Pgm genotypes have functional correlates that lead to significant variations in glycogen content of the honeybees and may have adaptive consequences.

We analyzed a total of 760 worker bees, two samples per colony, 390 colonies in 26 provinces in Turkey to determine and compare the genetic variation of Turkish honey bee (Apis mellifera L.) populations using 10 primers for RAPD and 6 microsatellite loci. Mean gene diversity levels ranged from 0.035 (Sanliurfa) to 0.175 (Antalya) for RAPD and 0.449 (Mugla) to 0.739 (Artvin) for microsatellite markers. Private band patterns and alleles, pairwise FST values support that the Anatolian honey bees belong to C lineage except for Hatay and Sanliurfa populations illustrated from previous findings of mitochondrial DNA studies. Genetic differentiation (GST) from RAPD data ranged from 0.060 (Bilecik and Mugla) to 0.395 (G&ouml / k&ccedil / eada and Sanliurfa). The genetic diversity (FST) for microsatellites ranged from -0.068 (G&ouml / k&ccedil / eada and &amp / #272 / zmir) to 0.347 (Konya and Mugla). The results of the present research are in agreement to that of previous study in Turkish honey bee populations which used different microsatellite loci. That is the genetic variation was the highest in African, the lowest in European and intermediate in the Mediterranean honey bee populations. The data presented here indicate that in spite of extensive migratory beekeeping, there is still a large genetic differentiation among honey bee populations. These results should be considered in establishment of conservation plans particularly in moving of colonies between regions. The most importantly introduction of bees with foreign origin and distribution queen bees from one center to all over the country which will homogenize the gene pool of the populations should be prevented

In this study, three subspecies of Apis mellifera L. (A. m. caucasica, A. m. carnica, and A. m. syriaca) from different climatic regions were evaluated electrophoretically at ontogenetic level by means of four enzymes, namely Phosphoglucomutase (PGM), Hexokinase (HK), Phosphoglucose isomerase (PGI) and Glukose-6-phosphate dehydrogenase (G6PD). It is determined that only Pgm and Hk loci were polymorphic. Allele and genotype frequencies at Pgm locus changes seasonally whereas Hk locus does not exhibit seasonal variation. Within the scope of this study we investigated at which developmental stage shifting to heterozygotes prior to winter occurs. It is found that there is a seasonal fluctuation throughout the year in Pgm genotype frequencies at each developmental stage studied and correlated with enzyme activity and glycogen content. As the studied enzymes have crucial v roles in insect energy metabolism, results of this study provided further information about the relationship between carbohydrate metabolism and enzyme polymorphism of honey bees.

No description available.

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.