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Morphometric, Mtdna And Microsatellite Analysis In Honeybee Populations (apis Mellifera L.) Of North And Northwest IranJabbarifarhoud, Houman 01 September 2004 (has links) (PDF)
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.
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Význam produkce a kvality pylu letní a podzimní pylové snůšky pro včelstvo (případová studie z okolí obce Volary - CHKO Šumava) / The importance of production and quality of pollen in the summer and late summer for the bee colonies (case studies from around of the village Volary - CHKO Šumava)PETROVÁ, Jana January 2015 (has links)
Objective of the work was to identify with using pollen analysis botanical origin of bee-colected pollens collected from beehive station Lískovec near the town Volary in the Protected Landscape Area of Šumava. Bee-collected pollens were collected once a week from one honey bee colony with using of a pollen trap. The time of collection was summer and late summer period from 22 June to 11 September 2010. Bee-collected pollens were dried, categorized by color, weighed and observed using the microscope. Pollen grains were determined by the number and type of apertures, shape, sculpture and size. Size of pollen grains was measured on at least 50 pollen grains of one type. In each microscopic slide were counted at least 500 pollen grains. The proportion of plant species in the sample was expressed as a percentage and the importace of plant species was evaluated in the diet of honey bees in the area of interest. Selected samples of bee-collected pollens from beehive station Lískovec and also from beehive station Dobčice were investigated for protein content and amino acid composition. Pollen belonging to Polemonium coeruleum, Trifolium pratense and Trifolium repens was evaluated as an important source of protein and amino acids for honey bees. The concentration of essential amino acids expressed as percentages of total amount of amino acids did not differ significantly between samples of bee-collected pollen. Another objective of the work was to compare the results from the area of interest with the results processed in the similar study from beehive station Dobčice in the northern area of the landscape Blanský les. The work also includes statistical evaluation of dominance, frequency, Shannon-Wiener index of diversity and variability between samples and species. The work is complemented by photographs of selected pollen grains.
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Telomere length compensation mechanisms as players in longevity and stress adaptation of insectsSÁBOVÁ, Michala January 2017 (has links)
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.
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Včelařsky významné pylodárné rostliny jarního a časně letního aspektu v okolí Volar na území CHKO Šumava / Important plants in terms of pollen for bee-keeping in the spring and early summer in the area of the protected landscape ŠumavaŠEMRO, Martin January 2014 (has links)
Objective of the work was to identify with using pollen analysis botanical origin of bee pollens. Pollen analysis consisted in the distribution of samples to individual sub-samples . Samples were weighed and a part of them was dissolved in a solution of glycerin and water. Dissolved samples were viewed under a microscope. Pollen was removed by the beekeeper Mgr .Milan Trhlín with using a device called pollen catcher. The samples were collected in the year 2011 in the spring and early summer period from beehive location on the hill Lískovec, of the protected landscape Šumava 1,8 km west of city Volary, at a time of 25. march to 24. june. Another objective of the work was with using phytocenology study, in the distance 1,5 km from the beehive habitat, evaluate the structure of plant association from the point of nutrition honeybees. The work also includes evaluation preference bees for individual plant species. There were detected, that bees prefer the plants that provide the best digest pollen and the plants which grows up to 1,5 km from beehive habitat. There were distinguised 32 types of pollen grains.
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Effects of Odorant-environment Complexity on Behavioral and Neural Plasticity at Different Time ScalesJanuary 2018 (has links)
abstract: The ability to detect and appropriately respond to chemical stimuli is important for many organisms, ranging from bacteria to multicellular animals. Responses to these stimuli can be plastic over multiple time scales. In the short-term, the synaptic strengths of neurons embedded in neural circuits can be modified and result in various forms of learning. In the long-term, the overall developmental trajectory of the olfactory network can be altered and synaptic strengths can be modified on a broad scale as a direct result of long-term (chronic) stimulus experience. Over evolutionary time the olfactory system can impose selection pressures that affect the odorants used in communication networks. On short time scales, I measured the effects of repeated alarm pheromone exposure on the colony-level defense behaviors in a social bee. I found that the responses to the alarm pheromone were plastic. This suggests that there may be mechanisms that affect individual plasticity to pheromones and regulate how these individuals act in groups to coordinate nest defense. On longer time scales, I measured the behavioral and neural affects of bees given a single chronic odor experience versus bees that had a natural, more diverse olfactory experience. The central brains of bees with a deprived odor experience responded more similarly to odorants in imaging studies, and did not develop a fully mature olfactory network. Additionally, these immature networks showed behavioral deficits when recalling odor mixture components. Over evolutionary time, signals need to engage the attention of and be easily recognized by bees. I measured responses of bees to a floral mixture and its constituent monomolecular components. I found that natural floral mixtures engage the orientation of bees’ antennae more strongly than single-component odorants and also provide more consistent central brain responses between stimulations. Together, these studies highlight the importance of olfactory experience on different scales and how the nervous system might impose pressures to select the stimuli used as signals in communication networks. / Dissertation/Thesis / Doctoral Dissertation Biology 2018
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Ontogeny of the pupal salivary, hypopharyngeal and mandibular glands and the role of apoptosis during metamorphosis in Apis melliferaJanuary 2018 (has links)
abstract: Amongst the most studied of the social insects, the honey bee has a prominent place due to its economic importance and influence on human societies. Honey bee colonies can have over 50,000 individuals, whose activities are coordinated by chemical signals called pheromones. Because these pheromones are secreted from various exocrine glands, the proper development and function of these glands are vital to colony dynamics. In this thesis, I present a study of the developmental ontogeny of the exocrine glands found in the head of the honey bee. In Chapter 2, I elucidate how the larval salivary gland transitions to an adult salivary gland through apoptosis and cell growth, differentiation and migration. I also explain the development of the hypopharyngeal and the mandibular gland using apoptotic markers and cytoskeletal markers like tubulin and actin. I explain the fundamental developmental plan for the formation of the glands and show that apoptosis plays an important role in the transformation toward an adult gland. / Dissertation/Thesis / Masters Thesis Biology 2018
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Decoding Brood Pheromone: The Releaser and Primer Effects of Young and Old Larvae on Honey Bee (Apis mellifera) WorkersJanuary 2014 (has links)
abstract: How a colony regulates the division of labor to forage for nutritional resources while accommodating for changes in colony demography is a fundamental question in the sociobiology of social insects. In honey bee, Apis mellifera, brood composition impacts the division of labor, but it is unknown if colonies adjust the allocation of foragers to carbohydrate and protein resources based on changes in the age demography of larvae and the pheromones they produce. Young and old larvae produce pheromones that differ in composition and volatility. In turn, nurses differentially provision larvae, feeding developing young worker larvae a surplus diet that is more queen-like in protein composition and food availability, while old larvae receive a diet that mimics the sugar composition of the queen larval diet but is restrictively fed instead of provided ad lib. This research investigated how larval age and the larval pheromone e-β ocimene (eβ) impact foraging activity and foraging load. Additional cage studies were conducted to determine if eβ interacts synergistically with queen mandibular pheromone (QMP) to suppress ovary activation and prime worker physiology for nursing behavior. Lastly, the priming effects of larval age and eβ on worker physiology and the transition from in-hive nursing tasks to outside foraging were examined. Results indicate that workers differentially respond to larvae of different ages, likely by detecting changes in the composition of the pheromones they emit. This resulted in adjustments to the foraging division of labor (pollen vs. nectar) to ensure that the nutritional needs of the colony's brood were met. For younger larvae and eβ, this resulted in a bias favoring pollen collection. The cage studies reveal that both eβ and QMP suppressed ovary activation, but the larval pheromone was more effective. Maturing in an environment of young or old larvae primed bees for nursing and impacted important endocrine titers involved in the transition to foraging, so bees maturing in the presence of larvae foraged earlier than control bees reared with no brood. / Dissertation/Thesis / Ph.D. Biology 2014
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Apiculture and Bee Health in Central SwedenLarne, Olof January 2014 (has links)
Pollination necessary for the agricultural crop production affects the functions of the ecosystems on earth. In landscapes where wild pollinators are decreasing, honey bees promote the maintenance of plant species, therefore honey bee losses are of great concern. Current honey bee colony losses (Apis mellifera) worldwide are caused by Colony collapse disorder, the mite Varroa destructor and pesticides. This results in the honey bees weakened immune defenses making them susceptible to different diseases. Studies show that long-term natural selection for coexistence, or resistance to Varroa mites by honey bees is possible, but further developments are needed for this application in managed beekeeping. Furthermore, lactic acid bacteria found in honey bees can play a crucial role by improving its immune response. At places where apicultural practices have led to decreased amounts of lactic acid bacteria in the bees, supplementary feeding is a possible treatment solution. The beekeepers' observations of mite reproduction dynamics and the overwintering of strong and healthy honey bees are needed to decrease Varroa treatment with synthetic chemicals. Based on this knowledge, a small survey of beekeepers in Örebro County, Sweden, was conducted in an attempt to determine the status of their bees during the last 5 years. The largest colony loss over the past 5 winters was predominantly in 2012-2013. Varroa mite infestations with disease symptoms were primarily found in the central region. Since the survey was small and time was limited it was only possible to make general conclusions. Deeper understanding of lactic acid bacteria in honey bee societies and their inhibition of different diseases are important for future research.
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The host-pathogen interface : characterising putative secreted proteins of the honeybee pathogen Nosema ceranae (Microsporidia )Thomas, Graham January 2015 (has links)
Microsporidia are obligate intracellular eukaryotic parasites related to fungi, possessing greatly reduced genomic and cellular components. The microsporidian Nosema ceranae threatens honeybee (Apis mellifera) populations. Nosemosis has a complex epidemiology affected by host, pathogen and environmental factors. Although a draft of the N. ceranae genome has been published, the molecular basis underpinning pathogenicity is not known. The lack of established culturing techniques and a tractable genetic system necessitates use of model systems for both host and parasite such as Saccharomyces cerevisiae. I hypothesise effectors essential to disease progression exist amongst N. ceranae secretome genes. In this study I have started characterising these genes using a combination of established and novel techniques for studying microsporidia proteins including bioinformatics, heterologous expression in S. cerevisiae, and the genome-wide analysis platform of Synthetic Genetic Arrays. This effort has yielded new insights into N. ceranae secreted proteins which lack similarity to known sequences. I identified N. ceranae protein NcS77 as a candidate effector implicated in targeting host nuclear pores. NcS50 and NcS85 co-localise with ERG6 a marker for lipid droplets (an organelle known to be targeted by another obligate intracellular pathogen Chlamydia trachomatis) when expressed in S. cerevisiae. N. ceranae polar tube proteins (PTP) induce filament formation when expressed in S. cerevisiae and PTP2 co-localises with the cell wall. Interestingly this phenotype is replicated by another secreted protein which may infer a common function. Together these data contribute to knowledge on N. ceranae pathology bringing us closer to understanding the disease and ultimately lead the way to mitigation.
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Biohemijski i fiziološki parametri stanja medonosne pčele (Apis mellifera L.) tokom letnjeg i zimskog perioda na staništima sa različitim antropogenim uticajem / Biochemical and physiological parameters of honey bee (Apis mellifera L.) during summer and winter in habitats with different anthropogenic influenceOrčić Snežana 30 September 2020 (has links)
<p>Medonosna pčela (Apis mellifera Linnaeus, 1758) je široko rasprostranjena vrsta iz grupe socijalnih insekata, glavni oprašivač mnogih divljih biljaka i poljoprivrednih kultura. Pored njene primarne uloge u oprašivanju, koristi se i za dobijanje pčelinjih proizvoda, pre svega meda, voska i propolisa, čime se dodatno naglašava njen privredni značaj. Uzimajući u obzir značaj medonosne pčele, a sa druge strane aktuelan problem pada broja kolonija, postoji potreba za razumevanje uzroka i procenu rizika koji leže u osnovi ovog kompleksnog problema. Stoga, istraživanja u ovoj doktorskoj disertaciji obuhvataju praćenje biohemijskih i fizioloških parametara kod medonosne pčele kao pokazatelja stanja pčelinjih zajednica tokom letnjeg i zimskog perioda na staništima sa različitim antropogenim uticajem. U prvoj fazi istraživanja su izvedeni akutni laboratorijski testovi izlaganja medonosne pčele subletalnim dozama pesticida, tiakloprida i klotianidina, a dobijeni rezultati su ukazali na narušenu neurotransmisiju, na izmene u aktivnosti antioksidativnih enzima i redoks statusa u ćeliji, kao i na imunosupresiju. U drugoj fazi istraživanja su analizirane kolonije medonosne pčele sa različitih lokaliteta na području AP Vojvodine, sa primenom stacionarnog i migratornog tipa pčelarenja, tokom letnjeg i zimskog perioda, a dobijeni rezultati su ukazali na značajne razlike u biohemijskom odgovoru medonosne pčele u zavisnosti od starosti pčela, sezone godine i tipa pčelinjaka. Na osnovu rezultata prethodne dve faze istraživanja, izvršen je odabir uzoraka, kao i izbor parametara za treću fazu istraživanja, gde je praćeno stanje medonosne pčele iz stacionalnih pčelinjih zajednica, tokom letnjeg aktivnog perioda, kao i početkom i krajem zimskog perioda mirovanja pčela, sa tri lokaliteta u Republici Srbiji sa različitim stepenom urbanizacije i industrijalizacije: Beograd kao urbano, Susek kao ruralno i Zajača kao industrijsko područje. Dobijeni rezultati su ukazali na značajne razlike u zavisnosti od sezone godine, kao i lokaliteta sa različitim antropogenim uticajem. Zimske pčele, krajem perioda mirovanja u odnosu na početak mirovanja, karakteriše viši nivo antioksidativne zaštite, udružen sa visokim stepenom oksidativnih oštećenja, zatim bolja imunokompetencija, kao i niske energetske rezerve u masnom telu. Sezonskim povećanjem temperatura tokom godine povećava se sadržaj zasićenih, dok se smanjuje udeo nezasićenih masnih kiselina, gde se oleinska 18:1(9) kiselina izdvaja kao dominantna komponenta u ukupnom sadržaju masnih kiselina masnog tela pčela sa sve tri lokacije, tokom sva tri perioda. Niži nivo ukupnih ugljovodonika je još jedna fiziološka karakteristika zimskih pčela. Takođe, zapažene su promene i u neurotransmisiji holinergičkog tipa tokom sezone, sa višim aktivnostima acetilholinesteraze kod pčela krajem zime i tokom leta. Metabolomičkom analizom hemolimfe pčela je identifikovano 125 metabolita, uključenih u 36 metaboličkih puteva, gde se kao biomarkeri od značaja za razlikovanje letnjih i zimskih pčela izdvajaju metaboliti u metabolizmu glicerolipida i aminokiseline glicin, cistein, glutamin, fenilalanin, prolin i lizin. Poređenjem dobijenih rezultata između različitih lokaliteta, pčele iz Beograda se izdvajaju sa nižim nivoom oksidativnog stresa, nižim aktivnostimaacetilholinesteraze, kao i fenol oksidaze i glukoza oksidaze, ključnih enzima u imunom odgovoru pčela. Pčele iz Suseka su se izdvojile sa najvećom masom masnog tela, što ukazuje na dobre nutritivne i energetske rezerve u pčelama tokom zime i leta, dok se Beograd izdvaja sa značajno višim udelom nezasićenih masnih kiselina u masnom telu pčela. Takođe su zabeležene razlike u relativnoj zastupljenosti n-alkana u pčelama sa različitih lokaliteta, te je u Beogradu najzastupljeniji nonakozan (C29), dok je heptakozan (C27) najzastupljeniji u uzorcima pčela iz Suseka i Zajače. Analizom sadržaja metala u pčelama, pergi i medu, zapažamo da svaku sredinu karakteriše specifičan profil zagađenja, kao i da je u medu znatno niža koncentracija svih analiziranih metala. Dobijeni rezultati pružaju dobru osnovu za dalja ispitivanja biološkog odgovora medonosne pčele, u pogledu uticaja faktora okruženja, a time i dalje definisanje odgovarajućih mera zaštite pčelinjih zajednica.</p> / <p>The honey bee (Apis mellifera Linnaeus, 1758) is a‚widespread social insect species and the main pollinator of various wild plants and agricultural crops.In addition to its primary role in pollination, the honey bee is also used for obtaining honeybee products, mostly honey, wax, and propolis, with a significant role in the economy. Number of honey bee colonies is declining, thus necessitating the assessment of underlying reasons and risks. Therefore, in this doctoral dissertation, biochemical and physiological parameters in the honey bee were monitored as indicators of the colonies’ condition during the summer and winter period in habitats with different anthropogenic impacts. In the first phase of the research, acute laboratory tests of honey bee exposure to sublethal doses of pesticides (thiacloprid and clothianidin) were performed and the obtained results indicated impaired neurotransmission, changes in the activity of antioxidant enzymes, and redox status in the cell, as well as immunosuppression. In the second phase of the research, honey bee colonies from different localities in the area of AP Vojvodina were analyzed, using the stationary and migratory types of beekeeping, during the summer and winter period, and the obtained results indicated significant differences in the biochemical response of the honey bee depending on the age of the bees, the season of the year, and the type of apiary. Based on the results of the previous two phases of the research, the selection of samples was performed, as well as the selection of parameters for analysis within the third phase of the research, where the condition of honey bees from stationary bee communities was monitored during the summer active period, as well as the beginning and end of winter dormancy of bees, from three localities in the Republic of Serbia with different degrees of urbanization and industrialization: Belgrade as urban, Susek as rural and<br />Zajaca as industrial area. The obtained results indicated significant differences depending on the season of the year, as well as the location with different anthropogenic influence. Older winter bees are characterized by a higher level of antioxidant protection, associated with a high degree of oxidative damage, better immunocompetence, as well as lowenergy reserves in the fat body. The seasonal increase in the temperature during the year increases the content of saturated while decreasing the ratio of unsaturated fatty acids, where oleic 18:1(9) acid stands out as the dominant component in the total fatty acid content of bee body fat from all three locations, during all three periods. The lower level of total hydrocarbons is another physiological characteristic of winter bees. Also, changes in cholinergic neurotransmission were observed during the season, with higher acetylcholinesterase activities in bees in late winter and summer. Metabolomic analysis of bee hemolymph identified 125 metabolites,included in 36 metabolic pathways, where metabolites in the metabolism of glycerolipids and amino acids glycine, cysteine, glutamine, phenylalanine, proline, and lysine stand out as biomarkers of importance for distinguishing summer and winter bees. By comparing the obtained results between different localities, honey bees from Belgrade stand out with lower levels of oxidative stress, lower activities of acetylcholinesterase as well as phenoloxidase and glucose oxidase, key enzymes in the immune response of bees. The honey bees from Susek had the largest mass of the fat body, which indicates good nutritional and energy reserves in bees during winter and summer, while the honey bees from Belgrade were shown to have a significantly higher ratio of unsaturated fatty acids in the fat body of bees during the year. There were also differences in the relative prevalence of n-alkanes in honey bees from different localities, nonacosane (C29) being the most common in Belgrade, while heptacosane (C27) is most prevalent in honey bee samples from Susek and Zajaca. By analyzing the metal content in honey bees, perga, and honey, it was noted that each environment is characterized by a specific pollution profile, as well as that the concentration of all analyzed metals in honey is significantly lower compared to samples of bees and perga. The obtained results provide a good basis for further studies of the biological response of the honey bee, in terms of the influence of the environmental factors, enabling further defining of appropriate measures for the protection of honey bee colonies.</p>
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