Search

Financial support was granted by the Project RoBeeTech (grant POS CCE 206/20.07.2010 SMIS code 618/12460 to L.A.M., D.S.D. and R.F.A.M) and by Fundación Séneca (project 11961/PI/09) to P.D.L.R. and I.M. supported by the Ministry of Education, Culture and Sports., Both climatic and geographical factors play an important role for the biogeographical distribution of species. The Carpathian mountain ridge has been suggested as a natural geographical divide between the two honeybee subspecies Apis mellifera carnica and A. m. macedonica. We sampled one worker from one colony each at 138 traditional apiaries located across the Carpathians spanning from the Hungarian plains to the Danube delta. All samples were sequenced at the mitochondrial tRNALeu-cox2 intergenic region and genotyped at twelve microsatellite loci. The Carpathians had only limited impact on the biogeography because both subspecies were abundant on either side of the mountain ridge. In contrast, subspecies differentiation strongly correlated with the various temperature zones in Romania. A. m. carnica is more abundant in regions with the mean average temperature below 9 °C, whereas A. m. macedonica honeybees are more frequent in regions with mean temperatures above 9 °C. This range selection may have impact on the future biogeography in the light of anticipated global climatic changes., Depto. de Biodiversidad, Ecología y Evolución, Fac. de Ciencias Biológicas, TRUE, pub

The genetic profile of the Varroa destructor mite infesting Apis mellifera iberiensis colonies located in the Iberian Peninsula and also on Canarian and Balearic islands was determined through standard molecular assays (RFLP of the mitochondrial cox1 fragment). The V. destructor Korea haplotype was found in all of the 575 samples analyzed except in one, confirming the worldwide expansion of the more virulent haplotype. The mitochondrial haplotypes of the honey bees from an apiary where the Japan haplotype was detected were also determined, but no significant relationship was observed in the parasite-host haplotype distribution., Ministerio de Ciencia e Innovación (MCIN), Depto. de Biodiversidad, Ecología y Evolución, Depto. de Sanidad Animal, Fac. de Ciencias Biológicas, Fac. de Veterinaria, TRUE, pub

Financial support was provided by Fundación Séneca (project 11961/PI/09) to P De la Rúa, and by Fundação para a Ciência eTecnología and COMPETE/QREN/EU (Project PTDC/BIABEC/099640/2008) to M A Pinto. I Muñoz was supported by the Spanish Ministry of Education, Culture and Sports., Beekeeping practices such as the importation of non-native honey bee queens may interact with the conservation of honey bee biodiversity. Island honey bee populations are particularly appropriate to test the impact of the introduction of foreign subspecies into their genetic diversity and structure. Here we have used microsatellite markers to evaluate the temporal genetic variation over the last decade in Macaronesian honey bee populations, which have been exposed to different beekeeping strategies regarding queen importation as previously revealed by mitochondrial determination of the evolutionary lineage: a high level on Tenerife and São Miguel and absent or low on La Palma and Madeira. While genetic diversity remained low (from 0.402 to 0.483 in the previous survey and from 0.390 to 0.513 in the current survey), genetic introgression from foreign honey bees was detected on Tenerife and São Miguel based on Bayesian structure analysis. Nevertheless, the existence of endemic honey bee populations deserving conservation on the Macaronesian Islands can still be inferred from the aforementioned analyses., Depto. de Biodiversidad, Ecología y Evolución, Fac. de Ciencias Biológicas, TRUE, pub

Novel transmission routes can allow infectious diseases to spread, often with devastating consequences. Ectoparasitic varroa mites vector a diversity of RNA viruses, having switched hosts from the eastern to western honey bees (Apis cerana to Apis mellifera). They provide an opportunity to explore how novel transmission routes shape disease epidemiology. As the principal driver of the spread of deformed wing viruses (mainly DWV-A and DWV-B), varroa infestation has also driven global honey bee health declines. The more virulent DWV-B strain has been replacing the original DWV-A strain in many regions over the past two decades. Yet, how these viruses originated and spread remains poorly understood. Here, we use a phylogeographic analysis based on whole-genome data to reconstruct the origins and demography of DWV spread. We found that, rather than reemerging in western honey bees after varroa switched hosts, as suggested by previous work, DWV-A most likely originated in East Asia and spread in the mid-20th century. It also showed a massive population size expansion following the varroa host switch. By contrast, DWV-B was most likely acquired more recently from a source outside East Asia and appears absent from the original varroa host. These results highlight the dynamic nature of viral adaptation, whereby a vector's host switch can give rise to competing and increasingly virulent disease pandemics. The evolutionary novelty and rapid global spread of these host-virus interactions, together with observed spillover into other species, illustrate how increasing globalization poses urgent threats to biodiversity and food security.

The influence of genetic diversity and exposure to xenobiotics on the prevalence of pathogens was studied within the context of a voluntary epidemiological study in Spanish apiaries of Apis mellifera iberiensis, carried out during the spring season of years 2014 and 2015. As such, the evolutionary lineages of the honey bee colonies were identified, a multiresidue analysis of xenobiotics was carried out in beebread and worker bee samples, and the Toxic Unit (TUm) was estimated for each sampled apiary. The relationship between lineages and the most prevalent pathogens (Nosema ceranae, Varroa destructor, trypanosomatids, Black Queen Cell Virus; and Deformed Wing Virus) was analysed with contingency tables, and the possible relationships between TUm and the prevalence of these pathogens were studied by using a factor analysis. The statistical analysis supported the associations between V. destructor and Deformed Wing Virus (DWV), and between N. ceranae and Black Queen Cell Virus (BQCV), but the association between these pathogens and trypanosomatids was not observed. TUm values varied between 5.5 × 10-6 and 3.65 × 10-1. When TUm < 3.35 × 10-4, it was mainly determined by coumaphos, tau-fluvalinate and/or chlorfenvinphos. At higher values, other insecticides also contributed to TUm, although a clear predominance was not seen up to TUm ≥ 1.83 × 10-2, when it was mainly defined by acrinathrin, spinosad and/or imidacloprid. The possible cumulative effect from the joint action of xenobiotics was >10% in the 63% of the cases. The prevalence of pathogens did not appear to be influenced by the distribution of evolutionary lineages and, while the prevalence of V. destructor was not found to be determined by TUm, there was a trend towards an increasing prevalence of N. ceranae when TUm ≥ 23 10-4. This study is an example of using TUm approach beyond the field of the ecotoxicology.