Publications

israeli acute paralysis virus infection leads to an enhanced rna interference response and not its suppression in the bumblebee bombus terrestris.	rna interference (rnai) is the primary antiviral defense system in insects and its importance for pollinator health is indisputable. in this work, we examined the effect of israeli acute paralysis virus (iapv) infection on the rnai process in the bumblebee, bombus terrestris, and whether the presence of possible functional viral suppressors could alter the potency of the host's immune response. for this, a two-fold approach was used. through a functional rnai assay, we observed an enhancement of ...	2016	27999371
unbiased rna shotgun metagenomics in social and solitary wild bees detects associations with eukaryote parasites and new viruses.	the diversity of eukaryote organisms and viruses associated with wild bees remains poorly characterized in contrast to the well-documented pathosphere of the western honey bee, apis mellifera. using a deliberate rna shotgun metagenomic sequencing strategy in combination with a dedicated bioinformatics workflow, we identified the (micro-)organisms and viruses associated with two bumble bee hosts, bombus terrestris and bombus pascuorum, and two solitary bee hosts, osmia cornuta and andrena vaga. i ...	2016	28006002
direct determination of the mutation rate in the bumblebee reveals evidence for weak recombination-associated mutation and an approximate rate constancy in insects.	accurate knowledge of the mutation rate provides a base line for inferring expected rates of evolution, for testing evolutionary hypotheses and for estimation of key parameters. advances in sequencing technology now permit direct estimates of the mutation rate from sequencing of close relatives. within insects there have been three prior such estimates, two in nonsocial insects (drosophila: 2.8 × 10(-)(9) per bp per haploid genome per generation; heliconius: 2.9 × 10(-)(9)) and one in a social s ...	2017	28007973
evaluation of the toxicity of fungicides to flight muscle mitochondria of bumblebee (bombus terrestris l.).	insects pollinate 75% of crops used for human consumption. over the last decade, a substantial reduction in the abundance of pollinating insects has been recorded and recognized as a severe matter for food supply security. many of the important food crops destined for human consumption are grown in greenhouses. a unique feature of greenhouse agriculture is the extensive use of fungicides to curb multiple fungal infections. the most widely used pollinating insects in greenhouses are commercially ...	2017	28043329
long-term prevalence of the protists crithidia bombi and apicystis bombi and detection of the microsporidium nosema bombi in invasive bumble bees.	an initial survey in 2009 carried out at a site in northwestern patagonia region, argentina, revealed for the first time in south america the presence of the flagellate crithidia bombi and the neogregarine apicystis bombi, two pathogens associated with the palaearctic invasive bumble bee bombus terrestris. in order to determine the long-term persistence and dynamics of this microparasite complex, four additional collections at the same site (san carlos de bariloche) were conducted along the foll ...	2017	28085231
a new method for quick and easy hemolymph collection from apidae adults.	bio-analysis of insects is increasingly dependent on highly sensitive methods that require high quality biological material, such as hemolymph. however, it is difficult to collect fresh and uncontaminated hemolymph from adult bees since they are very active and have the potential to sting, and because hemolymph is rapidly melanized. here we aimed to develop and test a quick and easy method for sterile and contamination-free hemolymph sampling from adult apidae. our novel antennae method for hemo ...	2017	28125668
the combined effects of a monotonous diet and exposure to thiamethoxam on the performance of bumblebee micro-colonies.	there is a pressing need to better understand the factors contributing to declines of wild pollinators such as bumblebees. many different contributors have been postulated including: loss of flower-rich habitats and nesting sites; monotonous diets; impacts of invasive pathogens; exposure to pesticides such as neonicotinoids. past research has tended to investigate the impacts of these stressors in isolation, despite the increasing recognition that bees are simultaneously exposed to a combination ...	2017	28135666
separation of different pollen types by chemotactile sensing in bombus terrestris.	when tasting food, animals rely on chemical and tactile cues, which determine the animal's decision on whether or not to eat food. as food nutritional composition has enormous consequences for the survival of animals, food items should generally be tasted before they are eaten or collected for later consumption. even though recent studies confirmed the importance of e.g. gustatory cues, compared to olfaction only little is known about the representation of chemotactile stimuli at the receptor le ...	2017	28183868
differences in pollination success between local and foreign flower color phenotypes: a translocation experiment with gentiana lutea (gentianaceae).	the adaptive maintenance of flower color variation is frequently attributed to pollinators partly because they preferentially visit certain flower phenotypes. we tested whether gentiana lutea-which shows a flower color variation (from orange to yellow) in the cantabrian mountains range (north of spain)-is locally adapted to the pollinator community.	2017	28194308
bumblebees can discriminate between scent-marks deposited by conspecifics.	bumblebees secrete a substance from their tarsi wherever they land, which can be detected by conspecifics. these secretions are referred to as scent-marks, which bumblebees are able to use as social cues. although it has been found that bumblebees can detect and associate scent-marks with rewarding or unrewarding flowers, their ability at discriminating between scent-marks from bumblebees of differing relatedness is unknown. we performed three separate experiments with bumblebees (bombus terrest ...	2017	28266572
do foraging bumblebees scent-mark food sources and does it matter?	the foraging of worker bees of bombus terrestris visiting artificial feeders in a climatic test chamber was investigated. the behaviour of worker bees visiting rewarding and unrewarding feeders is completely different. of all flower visits to rewarding feeders 94% are probing-visits, i.e. the bees land on the flower and probe for nectar. in contrast, only 0.3% of all visits to unrewarding feeders are probing-visits, whereas 47% are approach-visits, i.e., the bees approach the feeders without lan ...	1990	28313149
bumblebees require visual pollen stimuli to initiate and multimodal stimuli to complete a full behavioral sequence in close-range flower orientation.	flower visits are complex encounters, in which animals are attracted by floral signals, guided toward the site of the first physical contact with a flower, land, and finally take up floral rewards. at close range, signals of stamens and pollen play an important role to facilitate flower handling in bees, yet the pollen stimuli eliciting behavioral responses are poorly known. in this study, we test the response of flower-naive bumblebees (bombus terrestris) toward single and multimodal pollen sti ...	2017	28331576
fast learning in free-foraging bumble bees is negatively correlated with lifetime resource collection.	despite widespread interest in the potential adaptive value of individual differences in cognition, few studies have attempted to address the question of how variation in learning and memory impacts their performance in natural environments. using a novel split-colony experimental design we evaluated visual learning performance of foraging naïve bumble bees (bombus terrestris) in an ecologically relevant associative learning task under controlled laboratory conditions, before monitoring the life ...	2017	28356567
condition-dependent virulence of slow bee paralysis virus in bombus terrestris: are the impacts of honeybee viruses in wild pollinators underestimated?	slow bee paralysis virus (sbpv)-previously considered an obligate honeybee disease-is now known to be prevalent in bumblebee species. sbpv is highly virulent in honeybees in association with varroa mites, but has been considered relatively benign otherwise. however, condition-dependent pathogens can appear asymptomatic under good, resource abundant conditions, and negative impacts on host fitness may only become apparent when under stressful or resource-limited conditions. we tested whether sbpv ...	2017	28361244
micrornas associated with caste determination and differentiation in a primitively eusocial insect.	in eusocial hymenoptera (ants, bees and wasps), queen and worker adult castes typically arise via environmental influences. a fundamental challenge is to understand how a single genome can thereby produce alternative phenotypes. a powerful approach is to compare the molecular basis of caste determination and differentiation along the evolutionary trajectory between primitively and advanced eusocial species, which have, respectively, relatively undifferentiated and strongly differentiated adult c ...	2017	28361900
infections of virulent and avirulent viruses differentially influenced the expression of dicer-1, ago-1, and micrornas in bombus terrestris.	the microrna (mirna) pathway is well established to be involved in host-pathogen interactions. as key insect pollinators, bees are suffering from widely spreading viruses, especially honeybees and bumblebees. in order to better understand bee-virus interaction, we comparatively analyzed the involvement of the bumblebee mirna pathway upon infection by two different viruses. in our setup, an avirulent infection is induced by slow bee paralysis virus (sbpv) and a virulent infection is induced by is ...	2017	28374846