Genetic diversity of honey bee (Apis mellifera L.: Hymenoptera: Apidae) populations in Turkey revealed by RAPD markers

WOS: 000298506200003The honeybee, Apis mellifera L. is an ecologically and economically important insect species. Recent honey bee losses causing decline of bee diversity is found alarming for the pollination of both wild plant biodiversity and crop production. Therefore, determination of genetic diversity of honey bee populations is essential and will provide a valuable resource for conservation purposes. Twenty Random Amplified Polymorphic DNA (RAPD) primers were used to assess the genetic diversity in 720 worker bees collected from 360 colonies of 25 provinces in Turkey. Ten out of twenty primers produced 105 reproducible, bright bands, all were polymorphic. Mean genetic diversity values ranged between 0.035 and 0.175, coefficient of gene differentiation (G(ST)) values were estimated as 0.060 to 0.441, and the private band patterns reflected a high level of genetic variation. Analysis of Molecular Variance (AMOVA) partitioned the total genetic variation as 60% within, 40% among populations. The Mantel test did not reveal significant correlation between the genetic and geographic distances. First three Eigen values of principle coordinate analysis explained 63% of total variation, 27, 21, and 15% for the first, second and third respectively. The cluster analysis showed that the honey bees of Thrace region of Turkey and an island at a short distance were clustered together. The other two populations from southeastern Anatolia which belong to African lineage according to mitochondrial DNA analysis formed a separate cluster and rest of the populations which belong to north Mediterranean branch (C lineage) formed the third cluster. The results showed that genetic variability of honey bee populations from Turkey are determined using RAPD markers and provide information for future management and conservation plans.Middle East Technical UniversityMiddle East Technical University [DPT-2004K120510]We are thankful to the beekeepers for their help in collecting samples and to the Faculty Development Program (OYP) of the Middle East Technical University for the financial support (DPT-2004K120510)

Türkiye Bal Arıları Genetik Farklarının Koloni Dayanıklılığına (Vitality) Etkileri

TÜBİTAK KBAG Proje01.11.201

Phylogeography and population genetics of honey bees (Apis mellifera) from Turkey based on COI-COII sequence data

A study that involved DNA sequencing of COI-COII intergenic region of the mitochondrial DNA genome of Apis mellifera honey bees from Turkey was conducted to determine the population genetics and phylogeographic structure of this species from seven distinct areas of Turkey. From the 132 honey bees subjected to DNA sequencing, a total of 12 mitotypes of A. mellifera "C" lineage were observed, of which only one mitotype, C 13, had been reported previously. The most common mitotype, C12, accounted for 47% of the Apis mellifera "C" lineage samples and was found in 13 of the 22 sampled locations. This mitotype was also the basal ancestral mitotype based on TCS spanning tree analysis. The greatest amount of genetic diversity was observed in Bursa, where 4 mitotypes of the A. mellifera "C" lineage were unique to this location. Wright's F-statistics revealed that Artvin and Bursa were the most genetically distinct locations relative to the other sampled locations. Applying a molecular clock, Turkish A. mellifera "C" lineage mitotypes have been diverging for approximately 10,000 to 16,500 yr. based on phylogenetic analysis. In addition, two A. m. syriaca samples were observed from Hatay, Turkey. Phylogenetic analysis which included other A. mellifera subspecies confirms the subspecies relationships of A. mellifera "C" lineage, and A. m. syriaca. this study corroborates other studies that show Turkey to be a reservoir of genetically distinct populations of A. mellifera "C" lineage, which can be useful for developing genetic conservation strategies for A. mellifera

Managed honey bee colony losses in Canada, China, Europe, Israel and Turkey, for the winters of 2008-9 and 1009-10

In 2008 the COLOSS network was formed by honey bee experts from Europe and the USA. The primary objectives set by this scientific network were to explain and to prevent large scale losses of honey bee (Apis mellifera) colonies. In June 2008 COLOSS obtained four years support from the European Union from COST and was designated as COST Action FA0803 – COLOSS (Prevention of honey bee COlony LOSSes). To enable the comparison of loss data between participating countries, a standardized COLOSS questionnaire was developed. Using this questionnaire information on honey bee losses has been collected over two years. Survey data presented in this study were gathered in 2009 from 12 countries and in 2010 from 24 countries. Mean honey bee losses in Europe varied widely, between 7-22% over the 2008-9 winter and between 7-30% over the 2009-10 winter. An important finding is that for all countries which participated in 2008-9, winter losses in 2009-10 were found to be substantially higher. In 2009-10, winter losses in South East Europe were at such a low level that the factors causing the losses in other parts of Europe were absent, or at a level which did not affect colony survival. The five provinces of China, which were included in 2009-10, showed very low mean (4%) A. mellifera winter losses. In six Canadian provinces, mean winter losses in 2010 varied between 16-25%, losses in Nova Scotia (40%) being exceptionally high. In most countries and in both monitoring years, hobbyist beekeepers (1-50 colonies) experienced higher losses than practitioners with intermediate beekeeping operations (51-500 colonies). This relationship between scale of beekeeping and extent of losses effect was also observed in 2009-10, but was less pronounced. In Belgium, Italy, the Netherlands and Poland, 2008-9 mean winter losses for beekeepers who reported ‘disappeared’ colonies were significantly higher compared to mean winter losses of beekeepers who did not report ‘disappeared’ colonies. Mean 2008-9 winter losses for those beekeepers in the Netherlands who reported symptoms similar to “Colony Collapse Disorder” (CCD), namely: 1. no dead bees in or surrounding the hive while; 2. capped brood was present, were significantly higher than mean winter losses for those beekeepers who reported ‘disappeared’ colonies without the presence of capped brood in the empty hives. In the winter of 2009-10 in the majority of participating countries, beekeepers who reported ‘disappeared’ colonies experienced higher winter losses compared with beekeepers, who experienced winter losses but did not report ‘disappeared’ colonies

Appetitive reversal learning differences of two honey bee subspecies with different foraging behaviors

We aimed to examine mechanistically the observed foraging differences across two honey bee, Apis mellifera, subspecies using the proboscis extension response assay. Specifically, we compared differences in appetitive reversal learning ability between honey bee subspecies: Apis mellifera caucasica (Pollman), and Apis mellifera syriaca (Skorikov) in a “common garden” apiary. It was hypothesized that specific learning differences could explain previously observed foraging behavior differences of these subspecies: A.m. caucasica switches between different flower color morphs in response to reward variability, and A.m. syriaca does not switch. We suggest that flower constancy allows reduced exposure by minimizing search and handling time, whereas plasticity is important when maximizing harvest in preparation for long winter is at a premium. In the initial or Acquisition phase of the test we examined specifically discrimination learning, where bees were trained to respond to a paired conditioned stimulus with an unconditioned stimulus and not to respond to a second conditioned stimulus that is not followed by an unconditioned stimulus. We found no significant differences among the subspecies in the Acquisition phase in appetitive learning. During the second, Reversal phase of the experiment, where flexibility in association was tested, the paired and unpaired conditioned stimuli were reversed. During the Reversal phase A.m. syriaca showed a reduced ability to learn the reverse association in the appetitive learning task. This observation is consistent with the hypothesis that A.m. syriaca foragers cannot change the foraging choice because of lack of flexibility in appetitive associations under changing contingencies. Interestingly, both subspecies continued responding to the previously rewarded conditioned stimulus in the reversal phase. We discuss potential ecological correlates and molecular underpinnings of these differences in learning across the two subspecies. In addition, in a supplemental experiment we demonstrated that these differences in appetitive reversal learning do not occur in other learning contexts.National Science Foundation (NSF)Publisher's Versio

Proboscis conditioning experiments with honeybees, Apis mellifera caucasica, with butyric acid and DEET mixture as conditioned and unconditioned stimuli

Three experiments are described investigating whether olfactory repellents DEET and butyric acid can support the classical conditioning of proboscis extension in the honeybee, Apis mellifera caucasica (Hymenoptera: Apidae). In the first experiment DEET and butyric acid readily led to standard acquisition and extinction effects, which are comparable to the use of cinnamon as a conditioned stimulus. These results demonstrate that the odor of DEET or butyric acid is not intrinsically repellent to honey bees. In a second experiment, with DEET and butyric acid mixed with sucrose as an unconditioned stimulus, proboscis conditioning was not established. After several trials, few animals responded to the unconditioned stimulus. These results demonstrate that these chemicals are gustatory repellents when in direct contact. In the last experiment a conditioned suppression paradigm was used. Exposing animals to butyric acid or DEET when the proboscis was extended by direct sucrose stimulation or by learning revealed that retraction of the proboscis was similar to another novel odor, lavender, and in all cases greatest when the animal was not permitted to feed. These results again demonstrate that DEET or butyric acid are not olfactory repellents, and in addition, conditioned suppression is influenced by feeding state of the bee.Peer reviewedPsychologyZoolog

Queen rearing and selection practices and their impact on the genetic diversity and fitness of honey bee colonies

The Apimondia working group on honey bee diversity and fitness (AWG 7) was created on October 25, 2010 as a Scientific Working Group of Apimondia. The aim of this AWG is to collect information on honey bee queen rearing practices, and examine their impact on the genetic variability and general health of honey bee colonies. The AWG consists of 23 members from 16 different countries. The world wide survey being conducted by this AWG is focused on gathering information on how selection methods, instrumental insemination, disease management procedures, introduction of exotic bee lines, queen replacement strategies, and loss of local colony populations due to introduced parasites and pathogens, affect the ability of our bees to survive and reproduce. The information collected will contribute on an international level to our understanding of how apiculture practices affect honey bee genetics, health and productivity

Honey Bee Diversity Is Swayed by Migratory Beekeeping and Trade Despite Conservation Practices: Genetic Evidence for the Impact of Anthropogenic Factors on Population Structure

The intense admixture of honey bee (Apis mellifera L.) populations at a global scale is mostly attributed to the widespread migratory beekeeping practices and replacement of queens and colonies with non-native races or hybrids of different subspecies. These practices are also common in Anatolia and Thrace, but their influence on the genetic make-up of the five native subspecies of honey bees has not been explored. Here, we present an analysis of 30 microsatellite markers from honey bees from six different regions in Anatolia and Thrace (N = 250 samples), with the aim of comparing the impact of: (1) migratory beekeeping, (2) queen and colony trade, and (3) conservation efforts on the genetic structure of native populations. Populations exposed to migratory beekeeping showed less allegiance than stationary ones. We found genetic evidence for migratory colonies, acting as a hybrid zone mobile in space and time, becoming vectors of otherwise local gene combinations. The effect of honey bee trade leaves very high introgression levels in native honey bees. Despite their narrow geographic range, introgression occurs mainly with the highly commercial Caucasian bees. We also measured the direction and magnitude of gene flow associated with bee trade. A comparison between regions that are open and those closed to migratory beekeeping allowed the evaluation of conservation sites as centers with limited gene flow and demonstrated the importance of establishing such isolated regions. Despite evidence of gene flow, our findings confirm high levels of geographically structured genetic diversity in four subspecies of honey bees in Turkey and emphasize the need to develop policies to maintain this diversity. Our overall results are of interest to the wider scientific community studying anthropogenic effects on the population diversity of honey bees and other insects. Our findings on the effects of migratory beekeeping, replacement of queens and colonies have implications for the conservation of honey bees, other pollinators, and invertebrates, in general, and are informative for policy-makers and other stakeholders in Europe and beyond