In a honey bee colony, the queen uses queen mandibular pheromone (QMP) to induce young worker bees to feed and groom her. Among its many behavioural and physiological effects, QMP reduces dopamine levels in the brains of young worker bees. Dopamine is a biogenic monoamine involved in numerous functions including motor control and aversive learning. This study investigates the effects of QMP on motor activities and aversive learning behaviour and the potential link between QMP and dopamine levels in the brain of young bees. In young bees under the age of 15-days, QMP dramatically reduced locomotor activity and inhibited aversive learning behaviour. Interestingly in older bees these behaviours were not affected by pheromone. Treating young bees with the dopamine precursor, L-dopa (3.25 [mu]g/mI), partially rescued the levels of locomotor activity in QMP-treated bees, and reduced QMP�s effects on aversive learning. This suggests that blocking effects of QMP on both locomotor activity and aversive learning result at least in part from QMP-induced changes in brain dopamine levels. Two components of the QMP blend, 4-hydroxy-3-methoxyphenylethanol (HVA) and methyl p-hydroxybenzoate (HOB) were examined more closely. Both HVA and HOB are structurally similar to dopamine. HVA was found to mimic the effects of the full QMP blend on aversive learning. Treating bees with HVA reduced aversive learning in young bees. In contrast, treatment with HOB did not affect learning ability. This strongly suggests that HVA is one of the key components that mediates the actions of QMP on aversive learning. The final section of this thesis investigates why it might be advantageous to honey bee queens to block aversive learning and reduce locomotor activity in young worker bees. The study reveals age-related differences in behaviours that individual worker bees display towards QMP. Young bees reared with QMP or collected from a queenright hive showed attraction to QMP. Conversely, older bees displayed avoidance behaviour towards QMP. By blocking the establishment of aversive memories, young bees may be prevented from forming an association between QMP and any unpleasant side effects induced by this pheromone. This may confer significant benefit to the queen by increasing the likelihood of young workers remaining in her attendance.

The honeybee is one of the model species in insect olfaction and its sense of smell is well studied. However, knowledge about the spectrum of odorants detectable to honeybees is limited. One class of odorants that has never been tested so far are the amino acids, which are important constituents of floral nectar. The experiments reported here were conducted in order to (1) determine if the odor of amino acids is detectable to honeybees (Apis mellifera), and (2) determine olfactory detection thresholds in honeybees for detectable amino acid odors. To this end, the proboscis extension reflex, a classical conditioning paradigm that takes advantage of the honeybee’s ability to build a robust association between an odor stimulus and a nectar reward, was used. The results demonstrate that five out of 20 amino acids presented at 100 mM were detectable. The honeybees’ median olfactory detection thresholds for these five amino acids are 12 mM for L-tyrosine and L-cysteine, 50 mM for L-asparagine and L-tryptophan, and 100 mM for L-proline. These threshold values are high in comparison to naturally occurring concentrations in floral nectar, and compared to threshold values obtained in vertebrate species. One possible explanation for these findings is that the size of the olfactory receptor repertoire of honeybees limits their olfactory capabilities in terms of detectability and sensitivity for the odor of amino acids

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

During spring, it has been observed that several thousand bees leave their hive, and settle on some object such as a tree branch. Some of the scout bees search for a suitable place where a new hive can be set up, while the rest collect together to form a swarm. Heinrich (J. of Exp. Biology 91 (1981) 25; Science 212 (1981) 565; Scientific American 244:6 (1981) 147) has done some experiments with free and captive swarms. His observations are as follows. (1)The core (centre) temperature is around 35°C irrespective of the ambient temperature. (2)The mantle (outer surface) temperature exceeds the ambient temperature by 2- 3°C, provided the ambient temperature is greater than 20°C. Otherwise the mantle temperature is maintained around 17°C. (3) The temperature gradient vanishes just before take-off of the swarm. The present work attempts to predict temperature profiles in swarms and compare them with the data of Heinrich. A continuum model involving unsteady heat conduction and heat generation within the swarm is used. Heat loss from the outer surface of the swarm by free convection and radiation is accounted for approximately. To simplify the analysis, internal convection within the swarm is neglected. The energy balance equation is solved using the finite element method. The effective thermal conductivity (k) is determined by comparing model predictions with data for a swarm of dead bees. The estimated value of k is 0.20 W/m-K. Both spherical and a non-spherical axisymmetric shapes are considered. Considering axisymmetric swarms of live bees, temperature profiles are obtained using various heat generation functions which are available in literature. The effective thermal conductivity is assumed to be the same as that for the swarm of dead bees. Results based on a modified version of Southwick's heat generation function (The Behavior and Physiology of Bees, pp. 28-47, 1991) are qualitatively in accord with the data. The predicted maximum temperature within the swarm and the temperature at the lower surface of the swarm at the ambient temperature of 5°C are 34°C and 17-20°C, respectively. These are comparable to the measured values of 36°C and 19°C. The predicted maximum temperature within the swarm and the temperature at the lower surface of the swarm at the ambient temperature of 9°C are 36.5°C and 17-22°C, respectively. These are comparable to the measured values of 35°C and 19°C. The predicted oxygen consumption rates are 2.55 ml/g/hr for a swarm of 5284 bees at an ambient temperature Ta = 5°C and 1.15 ml/g/hr for 16,600 bees at Ta = 9°C. These are of the same order as the measured values (2 ml/g/hr for 5284 bees at Ta = 4.4DC and 0.45-0.55 ml/g/hr for 5284 bees at Ta = 10°C). Omholt and Lanvik (J. of Theoretical Biology, 120 (1986) 447) assumed a non-uniform steady state profile and used it to estimate the heat generation function. Using this function in the transient energy balance, it is found that their steady state profile is unstable.

No description available.

Apolipophorin-III is a hemolymph protein known for its role in lipid transport. Apolipophorin-III isolated from the hemolymph of last instar larvae of Galleria mellonella bound to the surface of the insect pathogenic Gram-negative bacterium Xenorhabdus nematophilus and to the lipid A moiety of its lipopolysaccharide. This binding reduced the toxicity of the lipopolysaccharide to hemocytes and decreased the inhibitory effect of the lipopolysaccharide on phenoloxidase. Apolipophorin-III also bound to the Gram-positive bacterium Micrococcus lysodeikticus; this enhanced the activity of hen egg lysozyme on the organism as well as the lytic activity of G. mellonella cell-free hemolymph. / The involvement of apolipophorin-III in the immune responses of G. mellonella larvae to lipoteichoic acids, surface components of Gram-positive bacteria, was examined. Lipoteichoic acids from Bacillus subtilis, Enterococcus hirae and Streptococcus pyogenes caused a dose- and time-dependent drop in the total counts of circulating hemocytes and a partial or complete depletion of plasmatocytes depending on the species of lipoteichoic acid. All lipoteichoic acids tested activated phenoloxidase in vitro; however, in vivo, only B. subtilis lipoteichoic acid elevated the phenoloxidase activity while the other two suppressed it. Binding of apolipophorin-III to lipoteichoic acids was demonstrated. Apolipophorin-III prevented the complete depletion of plasmatocytes and depressed the activation of phenoloxidase by lipoteichoic acid from B. subtilis. The concentration of apolipophorin-III in hemolymph two hours post injections of lipopolysaccharides or lipoteichoic acids into larvae of G. mellonella did not change with respect to control insects that received phosphate-buffered saline. The concentration of apolipophorin-III in hemolymph at the end of the feeding larval stage was 8--12 mg/mL of hemolymph. Apolipophorin-III was present in significant amounts in the prepupal, pupal and adult stages. The protein was detected immunologically in hemocyte lysates, plasma and fat body. Non-denaturing polyacrylamide gels and immunoblots of fresh hemolymph suggested that apolipophorin-III is associated with a 77 kDa protein.

Honeybees have a rich genetic diversity in Anatolia. This is reflected in the presence of numerous subspecies of honeybee in Turkey. In METU, Department of Biology, honeybee populations of different regions in Turkey are investigated in order to characterize population variation in these regions. A total of 23 length and angle features belonging to the honeybee hindlegs and forewings are measured in these studies using a microscope and a monitor. These measurements are carried out by placing rulers on the monitor that shows the honeybee image and getting the length and angle features. However, performing measurements in this way is a time consuming process and is open to human-dependent errors. In this thesis, a &ldquo / semi-automated honeybee feature extraction system&rdquo / is presented. The aim is to increase the efficiency by decreasing the time spent on handling these measurements and by increasing the accuracy of measured hindleg and forewing features. The problem is studied from the acquisition of the microscope images, to the feature extraction of the honeybee features. In this scope, suitable methods are developed for segmentation of honeybee hindleg and forewing images. Within intermediate steps, blob analysis is utilized, and edges of the forewing and hindlegs are thinned using skeletonization. Templates that represent the forewing and hindleg edges are formed by either Bezier Curves or Polynomial Interpolation. In the feature extraction phase, Active Contour (Snake) algorithm is applied to the images in order to find the critical points using these templates.

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.

In cranberry (Vaccinium macrocarpon Aiton) cultivation, farmers typically rent colonies of honey bee (Apis mellifera) for pollination. However, the efficiency of this bee at pollinating cranberries in Oregon, as in other regions, is questionable. Bumble bees (Bombus sp.) are reportedly effective in other regions, but their impact in Oregon is unknown. My objectives were to: (i) Compare bumble bee and honey bee pollination efficiencies under caged conditions; (ii) Estimate the abundance of bumble bees, honey bees, and other pollinators on an Oregon cranberry farm; and iii) Analyze and compare sources of pollen collected by bumble bees and honey bees in Oregon cranberries. In comparing pollination efficiencies of bumble bees and honey bees under caged conditions, the analysis of variance of data from the cage study indicated that bumble bee and honey bee pollinated plants yielded statistically equivalent average numbers of cranberries (1421 ± 302.5 and 1405 ± 347.6 berries/m², respectively) and weight of berries (11.5 ± 2.42 and 11.5 ± 2.77g/m²). However, bumble bees may have increased fruit set in honey bee treatments. On one occasion, bumble bees were found in the honey bee treatment, and may have contributed to the pollination of flowers in these plots. To estimate the abundance of pollinators, visual observations and were blue vane traps were utilized. Thirty-four timed visual observations in transects of cranberry beds were performed over on four dates during cranberry bloom. Blue vane traps were set-up on five occasions during bloom for two day periods. In the visual observations, honey bees (3.5 ± 0.58/min) were observed more frequently than bumble bees (1.2 ± 0.20/min). Bumble bees of four species made up 69.1% of trapped bees while honey bees made up 16.6% of bees caught in blue vane traps. On an Oregon cranberry farm during bloom periods in 2009, 2010 and 2011, pollen was collected from honey bee colonies using pollen traps. In 2010 and 2011, pollen was hand collected from reared bumble bee (B. vosnesenkii) colonies at the same farm. A total of 2937 honey bee pollen loads and 171 bumble bee pollen samples (137 scopal pollen loads, and 34 samples from with the colony) were individually acetolyzed and compared to a reference collection using light microscopy. Each pollen load was homogenized and 100 pollen grains were identified and counted to determine the percentage of each pollen type. Pollen collected by honey bees consisted of 29.1 ± 1.4% (2009), 18.3 ± 2.4% (2010), and 23.0 ± 1.1% (2011) cranberry pollen. Cranberry pollen contributed a higher percentage (56.0 ± 6.1%, and 70.4 ± 4.3% in 2010, and 2011, respectively) in bumble bee collected pollen. Both bee species collected pollen from non-target plants including those in the following families: Asteraceae, Fabaceae, Ranunculaceae, and Roseaceae. Native bumble bees (B. vosnesenskii) collected more cranberry pollen than pollen from non-target plants, and consistently collected a higher proportion of cranberry pollen than honey bees. The results of these studies suggest that native bumble bees may be adequate for cranberry pollination in Curry County, Oregon. However, the size of bumble bee populations may vary from year to year due to climactic conditions, availability of nesting sites, and forage before and after cranberry bloom. Thus the dependability and consistency pollination services rendered to cranberry crops by bumble bees needs to be further investigated in relation to population fluxuations. / Graduation date: 2012

In a honey bee colony, the queen uses queen mandibular pheromone (QMP) to induce young worker bees to feed and groom her. Among its many behavioural and physiological effects, QMP reduces dopamine levels in the brains of young worker bees. Dopamine is a biogenic monoamine involved in numerous functions including motor control and aversive learning. This study investigates the effects of QMP on motor activities and aversive learning behaviour and the potential link between QMP and dopamine levels in the brain of young bees. In young bees under the age of 15-days, QMP dramatically reduced locomotor activity and inhibited aversive learning behaviour. Interestingly in older bees these behaviours were not affected by pheromone. Treating young bees with the dopamine precursor, L-dopa (3.25 [mu]g/mI), partially rescued the levels of locomotor activity in QMP-treated bees, and reduced QMP�s effects on aversive learning. This suggests that blocking effects of QMP on both locomotor activity and aversive learning result at least in part from QMP-induced changes in brain dopamine levels. Two components of the QMP blend, 4-hydroxy-3-methoxyphenylethanol (HVA) and methyl p-hydroxybenzoate (HOB) were examined more closely. Both HVA and HOB are structurally similar to dopamine. HVA was found to mimic the effects of the full QMP blend on aversive learning. Treating bees with HVA reduced aversive learning in young bees. In contrast, treatment with HOB did not affect learning ability. This strongly suggests that HVA is one of the key components that mediates the actions of QMP on aversive learning. The final section of this thesis investigates why it might be advantageous to honey bee queens to block aversive learning and reduce locomotor activity in young worker bees. The study reveals age-related differences in behaviours that individual worker bees display towards QMP. Young bees reared with QMP or collected from a queenright hive showed attraction to QMP. Conversely, older bees displayed avoidance behaviour towards QMP. By blocking the establishment of aversive memories, young bees may be prevented from forming an association between QMP and any unpleasant side effects induced by this pheromone. This may confer significant benefit to the queen by increasing the likelihood of young workers remaining in her attendance.