| 1. |
- Bottero, Irene, et al.
(författare)
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Impact of landscape configuration and composition on pollinator communities across different European biogeographic regions
- 2023
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Ingår i: Frontiers in Ecology and Evolution. - 2296-701X. ; 11
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: Heterogeneity in composition and spatial configuration of landscape elements support diversity and abundance of flower-visiting insects, but this is likely dependent on taxonomic group, spatial scale, weather and climatic conditions, and is particularly impacted by agricultural intensification. Here, we analyzed the impacts of both aspects of landscape heterogeneity and the role of climatic and weather conditions on pollinating insect communities in two economically important mass-flowering crops across Europe. Methods: Using a standardized approach, we collected data on the abundance of five insect groups (honey bees, bumble bees, other bees, hover flies and butterflies) in eight oilseed rape and eight apple orchard sites (in crops and adjacent crop margins), across eight European countries (128 sites in total) encompassing four biogeographic regions, and quantified habitat heterogeneity by calculating relevant landscape metrics for composition (proportion and diversity of land-use types) and configuration (the aggregation and isolation of land-use patches). Results: We found that flower-visiting insects responded to landscape and climate parameters in taxon- and crop-specific ways. For example, landscape diversity was positively correlated with honey bee and solitary bee abundance in oilseed rape fields, and hover fly abundance in apple orchards. In apple sites, the total abundance of all pollinators, and particularly bumble bees and solitary bees, decreased with an increasing proportion of orchards in the surrounding landscape. In oilseed rape sites, less-intensively managed habitats (i.e., woodland, grassland, meadows, and hedgerows) positively influenced all pollinators, particularly bumble bees and butterflies. Additionally, our data showed that daily and annual temperature, as well as annual precipitation and precipitation seasonality, affects the abundance of flower-visiting insects, although, again, these impacts appeared to be taxon- or crop-specific. Discussion: Thus, in the context of global change, our findings emphasize the importance of understanding the role of taxon-specific responses to both changes in land use and climate, to ensure continued delivery of pollination services to pollinator-dependent crops.
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| 2. |
- Hodge, Simon, et al.
(författare)
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Design and Planning of a Transdisciplinary Investigation into Farmland Pollinators : Rationale, Co-Design, and Lessons Learned
- 2022
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Ingår i: Sustainability (Switzerland). - : MDPI AG. - 2071-1050. ; 14:17
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Tidskriftsartikel (refereegranskat)abstract
- To provide a complete portrayal of the multiple factors negatively impacting insects in agricultural landscapes it is necessary to assess the concurrent incidence, magnitude, and interactions among multiple stressors over substantial biogeographical scales. Trans-national ecological field investigations with wide-ranging stakeholders typically encounter numerous challenges during the design planning stages, not least that the scientific soundness of a spatially replicated study design must account for the substantial geographic and climatic variation among distant sites. ‘PoshBee’ (Pan-European assessment, monitoring, and mitigation of Stressors on the Health of Bees) is a multi-partner transdisciplinary agroecological project established to investigate the suite of stressors typically encountered by pollinating insects in European agricultural landscapes. To do this, PoshBee established a network of 128 study sites across eight European countries and collected over 50 measurements and samples relating to the nutritional, toxicological, pathogenic, and landscape components of the bees’ environment. This paper describes the development process, rationale, and end-result of each aspect of the of the PoshBee field investigation. We describe the main issues and challenges encountered during the design stages and highlight a number of actions or processes that may benefit other multi-partner research consortia planning similar large-scale studies. It was soon identified that in a multi-component study design process, the development of interaction and communication networks involving all collaborators and stakeholders requires considerable time and resources. It was also necessary at each planning stage to be mindful of the needs and objectives of all stakeholders and partners, and further challenges inevitably arose when practical limitations, such as time restrictions and labour constraints, were superimposed upon prototype study designs. To promote clarity for all stakeholders, for each sub-component of the study, there should be a clear record of the rationale and reasoning that outlines how the final design transpired, what compromises were made, and how the requirements of different stakeholders were accomplished. Ultimately, multi-national agroecological field studies such as PoshBee benefit greatly from the involvement of diverse stakeholders and partners, ranging from field ecologists, project managers, policy legislators, mathematical modelers, and farmer organisations. While the execution of the study highlighted the advantages and benefits of large-scale transdisciplinary projects, the long planning period emphasized the need to formally describe a design framework that could facilitate the design process of future multi-partner collaborations.
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| 3. |
- Nicholson, Charlie C, et al.
(författare)
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Pesticide use negatively affects bumble bees across European landscapes
- 2024
-
Ingår i: Nature. - 0028-0836 .- 1476-4687.
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Tidskriftsartikel (refereegranskat)abstract
- Sustainable agriculture requires balancing crop yields with the effects of pesticides on non-target organisms, such as bees and other crop pollinators. Field studies demonstrated that agricultural use of neonicotinoid insecticides can negatively affect wild bee species 1,2, leading to restrictions on these compounds 3. However, besides neonicotinoids, field-based evidence of the effects of landscape pesticide exposure on wild bees is lacking. Bees encounter many pesticides in agricultural landscapes 4-9 and the effects of this landscape exposure on colony growth and development of any bee species remains unknown. Here we show that the many pesticides found in bumble bee-collected pollen are associated with reduced colony performance during crop bloom, especially in simplified landscapes with intensive agricultural practices. Our results from 316 Bombus terrestris colonies at 106 agricultural sites across eight European countries confirm that the regulatory system fails to sufficiently prevent pesticide-related impacts on non-target organisms, even for a eusocial pollinator species in which colony size may buffer against such impacts 10,11. These findings support the need for postapproval monitoring of both pesticide exposure and effects to confirm that the regulatory process is sufficiently protective in limiting the collateral environmental damage of agricultural pesticide use.
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| 4. |
- Rodrigues De Miranda, Joachim, et al.
(författare)
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Cold case : The disappearance of Egypt bee virus, a fourth distinct master strain of deformed wing virus linked to honeybee mortality in 1970's Egypt
- 2022
-
Ingår i: Virology Journal. - : BioMed Central (BMC). - 1743-422X. ; 19:1
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Tidskriftsartikel (refereegranskat)abstract
- In 1977, a sample of diseased adult honeybees (Apis mellifera) from Egypt was found to contain large amounts of a previously unknown virus, Egypt bee virus, which was subsequently shown to be serologically related to deformed wing virus (DWV). By sequencing the original isolate, we demonstrate that Egypt bee virus is in fact a fourth unique, major variant of DWV (DWV-D): more closely related to DWV-C than to either DWV-A or DWV-B. DWV-A and DWV-B are the most common DWV variants worldwide due to their close relationship and transmission by Varroa destructor. However, we could not find any trace of DWV-D in several hundred RNA sequencing libraries from a worldwide selection of honeybee, varroa and bumblebee samples. This means that DWV-D has either become extinct, been replaced by other DWV variants better adapted to varroa-mediated transmission, or persists only in a narrow geographic or host range, isolated from common bee and beekeeping trade routes.
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| 5. |
- Engel, Philipp, et al.
(författare)
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The Bee Microbiome: Impact on Bee Health and Model for Evolution and Ecology of Host-Microbe Interactions
- 2016
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Ingår i: mBio. - : American Society for Microbiology. - 2161-2129 .- 2150-7511. ; 7:2
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Forskningsöversikt (refereegranskat)abstract
- As pollinators, bees are cornerstones for terrestrial ecosystem stability and key components in agricultural productivity. All animals, including bees, are associated with a diverse community of microbes, commonly referred to as the micro biome. The bee micro biome is likely to be a crucial factor affecting host health. However, with the exception of a few pathogens, the impacts of most members of the bee microbiome on host health are poorly understood. Further, the evolutionary and ecological forces that shape and change the microbiome are unclear. Here, we discuss recent progress in our understanding of the bee microbiome, and we present challenges associated with its investigation. We conclude that global coordination of research efforts is needed to fully understand the complex and highly dynamic nature of the interplay between the bee micro biome, its host, and the environment. High-throughput sequencing technologies are ideal for exploring complex biological systems, including host-microbe interactions. To maximize their value and to improve assessment of the factors affecting bee health, sequence data should be archived, curated, and analyzed in ways that promote the synthesis of different studies. To this end, the BeeBiome consortium aims to develop an online database which would provide reference sequences, archive metadata, and host analytical resources. The goal would be to support applied and fundamental research on bees and their associated microbes and to provide a collaborative framework for sharing primary data from different research programs, thus furthering our understanding of the bee microbiome and its impact on pollinator health.
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| 6. |
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| 7. |
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| 8. |
- Forsgren, Eva, et al.
(författare)
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Sample preservation, transport and processing strategies for honeybee RNA extraction: Influence on RNA yield, quality, target quantification and data normalization
- 2017
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Ingår i: Journal of Virological Methods. - : Elsevier BV. - 0166-0934 .- 1879-0984. ; 246, s. 81-89
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Tidskriftsartikel (refereegranskat)abstract
- Viral infections in managed honey bees are numerous, and most of them are caused by viruses with an RNA genome. Since RNA degrades rapidly, appropriate sample management and RNA extraction methods are imperative to get high quality RNA for downstream assays. This study evaluated the effect of various sampling transport scenarios (combinations of temperature, RNA stabilizers, and duration) of transport on six RNA quality parameters; yield, purity, integrity, cDNA synthesis efficiency, target detection and quantification. The use of water and extraction buffer were also compared for a primary bee tissue homogenate prior to RNA extraction. The strategy least affected by time was preservation of samples at -80 degrees C. All other regimens turned out to be poor alternatives unless the samples were frozen or processed within 24 h. Chemical stabilizers have the greatest impact on RNA quality and adding an extra homogenization step (a QIAshredder (TM) homogenizer) to the extraction protocol significantly improves the RNA yield and chemical purity. This study confirms that RIN values (RNA Integrity Number), should be used cautiously with bee RNA. Using water for the primary homogenate has no negative effect on RNA quality as long as this step is no longer than 15 min.
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| 9. |
- Forsgren, Eva, et al.
(författare)
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SLU:s verksamhet med bin
- 2016
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Ingår i: Bitidningen. - 0006-3886. ; , s. 11-15
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Tidskriftsartikel (populärvet., debatt m.m.)
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| 10. |
- Fries, Ingemar, et al.
(författare)
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The principal parasites and pathogens of honeybees
- 2011
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Ingår i: Bees in Europe and sustainable honey production (BEE SHOP) : results of a pan-european research network. - 9781612093369 ; , s. 49-105
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 11. |
- Fries, Ingemar, et al.
(författare)
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Verksamhet med bin 2010 vid SLU
- 2011
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Ingår i: Bitidningen. - 0006-3886. ; 109, s. 10-14
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Tidskriftsartikel (populärvet., debatt m.m.)
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| 12. |
- Fries, Ingemar, et al.
(författare)
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Verksamhet med bin vid SLU 2011.
- 2012
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Ingår i: Bitidningen. - 0006-3886. ; 111, s. 12-16
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Tidskriftsartikel (populärvet., debatt m.m.)
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| 13. |
- Fries, Ingemar, et al.
(författare)
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Verksamhet med bin vid SLU 2013
- 2014
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Ingår i: Bitidningen. - 0006-3886. ; 113, s. 16-19
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Tidskriftsartikel (populärvet., debatt m.m.)
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| 14. |
- Fries, Ingemar, et al.
(författare)
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Är GMO-grödor farliga för bin?
- 2014
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Ingår i: Bitidningen. - 0006-3886. ; , s. 32-33
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Tidskriftsartikel (populärvet., debatt m.m.)
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| 15. |
- Jagadish, Anupama, et al.
(författare)
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Development and optimization of a TaqMan assay for Nosema bombycis, causative agent of pebrine disease in Bombyx mori silkworm, based on the β-tubulin gene
- 2021
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Ingår i: Journal of Microbiological Methods. - : Elsevier BV. - 0167-7012 .- 1872-8359. ; 186
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Tidskriftsartikel (refereegranskat)abstract
- “Pébrine” is a devastating disease of Bombyx mori silkworms that is highly contagious and can completely destroy an entire crop of silkworms and is thus a serious threat for the viability and profitability of sericulture. The disease is most commonly attributed to microsporidians of the genus Nosema, which are obligate intracellular parasites that are transmitted through spores. Nosema infections in silkworms are diagnosed primarily through light microscopy, which is labour intensive and less reliable, sensitive, and specific than PCR-based techniques. Here, we present the development and optimization of a new TaqMan based assay targeting the β-tubulin gene in the pébrine disease causing agent Nosema bombycis in silkworms. The assay displayed excellent quantification linearity over multiple orders of magnitude of target amounts and a limit of detection (LOD) of 6.9 × 102 copies of target per reaction. The method is highly specific to N. bombycis with no cross-reactivity to other Nosema species commonly infecting wild silkworms. This specificity was due to three nucleotides in the probe-binding region unique to N. bombycis. The assay demonstrated a high reliability with a Coefficient of variation (CV) <5% for both intra-assay and inter-assay variability. The assay was used to trace experimental N. bombycis infection of silkworm larvae, in the fat body, midgut and ovary tissues, through pupation and metamorphosis to the emerging female moth, and her larval off-spring, confirming the vertical transmission of N. bombycis in silkworms. The TaqMan assay revealed a gradual increase in infection levels in the post-infection samples. The assay is reliable and simple to implement and can be a suitable complement to microscopy for routine diagnostics and surveillance in silkworm egg production centres with appropriate infrastructure.
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| 16. |
- Kardum Hjort, Cecilia, et al.
(författare)
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Genomic divergence and a lack of recent introgression between commercial and wild bumblebees (Bombus terrestris)
- 2022
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Ingår i: Evolutionary Applications. - : Wiley. - 1752-4571. ; 15:3, s. 365-382
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Tidskriftsartikel (refereegranskat)abstract
- The global movement of bees for agricultural pollination services can affect local pollinator populations via hybridization. When commercial bumblebees are of the same species but of different geographic origin, intraspecific hybridization may result in beneficial integration of new genetic variation, or alternatively may disrupt locally adapted gene complexes. However, neither the existence nor the extent of genomic introgression and evolutionary divergence between wild and commercial bumblebees is fully understood. We obtained whole-genome sequencing data from wild and commercial Bombus terrestris collected from sites in Southern Sweden with and without long-term use of commercially imported B. terrestris. We search for evidence of introgression, dispersal and genome-wide differentiation in a comparative genomic analysis of wild and commercial bumblebees. Commercial B. terrestris were found in natural environments near sites where commercial bumblebees were used, as well as drifting wild B. terrestris in commercial bumblebee colonies. However, we found no evidence for widespread, recent genomic introgression of commercial B. terrestris into local wild conspecific populations. We found that wild B. terrestris had significantly higher nucleotide diversity (Nei's pi, π), while the number of segregating sites (Watterson's theta, θw) was higher in commercial B. terrestris. A highly divergent region on chromosome 11 was identified in commercial B. terrestris and found to be enriched with structural variants. The genes present in this region are involved in flight muscle contraction and structure and pathogen immune response, providing evidence for differing evolutionary processes operating in wild and commercial B. terrestris. We did not find evidence for recent introgression, suggesting that co-occurring commercial B. terrestris have not disrupted evolutionary processes in wild B. terrestris populations.
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| 17. |
- Kawakami, Takeshi, et al.
(författare)
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Substantial Heritable Variation in Recombination Rate on Multiple Scales in Honeybees and Bumblebees
- 2019
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Ingår i: Genetics. - : GENETICS SOCIETY AMERICA. - 0016-6731 .- 1943-2631. ; 212:4, s. 1101-1119
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Tidskriftsartikel (refereegranskat)abstract
- Meiotic recombination shuffles genetic variation and promotes correct segregation of chromosomes. Rates of recombination vary on several scales, both within genomes and between individuals, and this variation is affected by both genetic and environmental factors. Social insects have extremely high rates of recombination, although the evolutionary causes of this are not known. Here, we estimate rates of crossovers and gene conversions in 22 colonies of the honeybee, Apis mellifera, and 9 colonies of the bumblebee, Bombus terrestris, using direct sequencing of 299 haploid drone offspring. We confirm that both species have extremely elevated crossover rates, with higher rates measured in the highly eusocial honeybee than the primitively social bumblebee. There are also significant differences in recombination rate between subspecies of honeybee. There is substantial variation in genome-wide recombination rate between individuals of both A. mellifera and B. terrestris and the distribution of these rates overlap between species. A large proportion of interindividual variation in recombination rate is heritable, which indicates the presence of variation in trans-acting factors that influence recombination genome-wide. We infer that levels of crossover interference are significantly lower in honeybees compared to bumblebees, which may be one mechanism that contributes to higher recombination rates in honeybees. We also find a significant increase in recombination rate with distance from the centromere, mirrored by methylation differences. We detect a strong transmission bias due to GC-biased gene conversion associated with noncrossover gene conversions. Our results shed light on the mechanistic causes of extreme rates of recombination in social insects and the genetic architecture of recombination rate variation.
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| 18. |
- Knapp, Jessica L, et al.
(författare)
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Ecological traits interact with landscape context to determine bees' pesticide risk
- 2023
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Ingår i: Nature Ecology and Evolution. - : Springer Science and Business Media LLC. - 2397-334X. ; 7, s. 547-556
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Tidskriftsartikel (refereegranskat)abstract
- Widespread contamination of ecosystems with pesticides threatens non-target organisms. However, the extent to which life-history traits affect pesticide exposure and resulting risk in different landscape contexts remains poorly understood. We address this for bees across an agricultural land-use gradient based on pesticide assays of pollen and nectar collected by Apis mellifera, Bombus terrestris and Osmia bicornis, representing extensive, intermediate and limited foraging traits. We found that extensive foragers (A. mellifera) experienced the highest pesticide risk-additive toxicity-weighted concentrations. However, only intermediate (B. terrestris) and limited foragers (O. bicornis) responded to landscape context-experiencing lower pesticide risk with less agricultural land. Pesticide risk correlated among bee species and between food sources and was greatest in A. mellifera-collected pollen-useful information for future postapproval pesticide monitoring. We provide foraging trait- and landscape-dependent information on the occurrence, concentration and identity of pesticides that bees encounter to estimate pesticide risk, which is necessary for more realistic risk assessment and essential information for tracking policy goals to reduce pesticide risk.
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| 19. |
- Lamei, Sepideh, et al.
(författare)
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Feeding Honeybee Colonies with Honeybee-Specific Lactic Acid Bacteria (Hbs-LAB) Does Not Affect Colony-Level Hbs-LAB Composition or Paenibacillus larvae Spore Levels, Although American Foulbrood Affected Colonies Harbor a More Diverse Hbs-LAB Community
- 2020
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Ingår i: Microbial Ecology. - : Springer Science and Business Media LLC. - 0095-3628 .- 1432-184X. ; 79:3, s. 743-755
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Tidskriftsartikel (refereegranskat)abstract
- The main current methods for controlling American Foulbrood (AFB) in honeybees, caused by the bacterial pathogen Paenibacillus larvae, are enforced incineration or prophylactic antibiotic treatment, neither of which is fully satisfactory. This has led to an increased interest in the natural relationships between the pathogenic and mutualistic microorganisms of the honeybee microbiome, in particular, the antagonistic effects of Honeybee-Specific Lactic Acid Bacteria (hbs-LAB) against P. larvae. We investigated whether supplemental administration of these bacteria affected P. larvae infection at colony level over an entire flowering season. Over the season, the supplements affected neither colony-level hbs-LAB composition nor naturally subclinical or clinical P. larvae spore levels. The composition of hbs-LAB in colonies was, however, more diverse in apiaries with a history of clinical AFB, although this was also unrelated to P. larvae spore levels. During the experiments, we also showed that qPCR could detect a wider range of hbs-LAB, with higher specificity and sensitivity than mass spectrometry. Honeybee colonies are complex super-organisms where social immune defenses, natural homeostatic mechanisms, and microbiome diversity and function play a major role in disease resistance. This means that observations made at the individual bee level cannot be simply extrapolated to infer similar effects at colony level. Although individual laboratory larval assays have clearly demonstrated the antagonistic effects of hbs-LAB on P. larvae infection, the results from the experiments presented here indicate that direct conversion of such practice to colony-level administration of live hbs-LAB is not effective.
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| 20. |
- Lamei, Sepideh, et al.
(författare)
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The secretome of honey bee-specific lactic acid bacteria inhibits Paenibacillus larvae growth
- 2019
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Ingår i: Journal of Apicultural Research. - : Informa UK Limited. - 0021-8839 .- 2078-6913. ; 58:3, s. 405-412
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Tidskriftsartikel (refereegranskat)abstract
- American Foulbrood (AFB) is a particularly pernicious bacterial disease of honey bees due to the extreme persistence of endospores of the causative agent Paenibacillus larvae. These spores are resistant to harsh environmental conditions, unaffected by antimicrobial agents and can remain viable for decades. The germination of the endospore in the larval midgut is the crucial first step leading to infection, followed by vegetative growth, tissue invasion and disease, culminating in spore formation when the host´s nutrients have been exhausted. Therefore, inhibiting spore germination or impeding early vegetative growth would be a highly effective strategy for limiting the impact of AFB. We previously showed that honey bee-specific lactic acid bacteria (hbs–LAB) had a major inhibitory effect on P. larvae both in culture and in larval bioassays. The present study documents the progress towards characterization of compounds, processes and interactions between P. larvae and the hbs–LAB responsible for this inhibitory effect. Firstly, we used an agar diffusion assay and larval infection bioassay to show that most, if not all, of the inhibitory effect was associated with the extracellular fraction (secretome). Secondly, we employed a turbidimetric growth assay to demonstrate that the hbs–LAB secretome strongly inhibited P. larvae vegetative growth, however, probably not by reducing spore germination. The inhibition was similarly effective against both major P. larvae genotypes (ERIC-I and II) in all experiments. The implications of our results for characterization of the secretome and for the management and treatment of AFB and P. larvae are further discussed.
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| 21. |
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| 22. |
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| 23. |
- Locke Grandér, Barbara, et al.
(författare)
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Adapted tolerance to virus infections in four geographically distinct Varroa destructor-resistant honeybee populations
- 2021
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Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 11
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Tidskriftsartikel (refereegranskat)abstract
- The ectoparasitic mite, Varroa destructor, is unarguably the leading cause of honeybee (Apis mellifera) mortality worldwide through its role as a vector for lethal viruses, in particular, strains of the Deformed wing virus (DWV) and Acute bee paralysis virus (ABPV) complexes. Several honeybee populations across Europe have well-documented adaptations of mite-resistant traits but little is known about host adaptations towards the virus infections vectored by the mite. The aim of this study was to assess and compare the possible contribution of adapted virus tolerance and/or resistance to the enhanced survival of four well-documented mite-resistant honeybee populations from Norway, Sweden, The Netherlands and France, in relation to unselected mite-susceptible honeybees. Caged adult bees and laboratory reared larvae, from colonies of these four populations, were inoculated with DWV and ABPV in a series of feeding infection experiments, while control groups received virus-free food. Virus infections were monitored using RT-qPCR assays in individuals sampled over a time course. In both adults and larvae the DWV and ABPV infection dynamics were nearly identical in all groups, but all mite-resistant honeybee populations had significantly higher survival rates compared to the mite-susceptible honeybees. These results suggest that adapted virus tolerance is an important component of survival mechanisms.
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| 24. |
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| 25. |
- Locke Grandér, Barbara, et al.
(författare)
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Increased Tolerance and Resistance to Virus Infections: A Possible Factor in the Survival of Varroa destructor-Resistant Honey Bees (Apis mellifera)
- 2014
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Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 9
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Tidskriftsartikel (refereegranskat)abstract
- The honey bee ectoparasitic mite, Varroa destructor, has a world-wide distribution and inflicts more damage than all other known apicultural diseases. However, Varroa-induced colony mortality is more accurately a result of secondary virus infections vectored by the mite. This means that honey bee resistance to Varroa may include resistance or tolerance to virus infections. The aim of this study was to see if this is the case for a unique population of mite-resistant (MR) European honey bees on the island of Gotland, Sweden. This population has survived uncontrolled mite infestation for over a decade, developing specific mite-related resistance traits to do so. Using RT-qPCR techniques, we monitored late season virus infections, Varroa mite infestation and honey bee colony population dynamics in the Gotland MR population and compared this to mite-susceptible (MS) colonies in a close by apiary. From summer to autumn the deformed wing virus (DWV) titres increased similarly between the MR and MS populations, while the black queen cell virus (BQCV) and sacbrood virus (SBV) titres decreased substantially in the MR population compared to the MS population by several orders of magnitude. The MR colonies all survived the following winter with high mite infestation, high DWV infection, small colony size and low proportions of autumn brood, while the MS colonies all perished. Possible explanations for these changes in virus titres and their relevance to Varroa resistance and colony winter survival are discussed.
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| 26. |
- Locke Grandér, Barbara, et al.
(författare)
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Persistence of subclinical deformed wing virus infections in honeybees following Varroa mite removal and a bee population turnover
- 2017
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Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 12
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Tidskriftsartikel (refereegranskat)abstract
- Deformed wing virus (DWV) is a lethal virus of honeybees (Apis mellifera) implicated in elevated colony mortality rates worldwide and facilitated through vector transmission by the ectoparasitic mite Varroa destructor. Clinical, symptomatic DWV infections are almost exclusively associated with high virus titres during pupal development, usually acquired through feeding by Varroa mites when reproducing on bee pupae. Control of the mite population, generally through acaricide treatment, is essential for breaking the DWV epidemic and minimizing colony losses. In this study, we evaluated the effectiveness of remedial mite control on clearing DWV from a colony. DWV titres in adult bees and pupae were monitored at 2 week intervals through summer and autumn in acaricide-treated and untreated colonies. The DWV titres in Apistan treated colonies was reduced 1000-fold relative to untreated colonies, which coincided with both the removal of mites and also a turnover of the bee population in the colony. This adult bee population turnover is probably more critical than previously realized for effective clearing of DWV infections. After this initial reduction, subclinical DWV titres persisted and even increased again gradually during autumn, demonstrating that alternative non-Varroa transmission routes can maintain the DWV titres at significant subclinical levels even after mite removal. The implications of these results for practical recommendations to mitigate deleterious subclinical DWV infections and improving honeybee health management are discussed.
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| 27. |
- Locke Grandér, Barbara, et al.
(författare)
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Rapid parallel evolution overcomes global honey bee parasite
- 2018
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Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 8
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Tidskriftsartikel (refereegranskat)abstract
- In eusocial insect colonies nestmates cooperate to combat parasites, a trait called social immunity. However, social immunity failed for Western honey bees (Apis mellifera) when the ectoparasitic mite Varroa destructor switched hosts from Eastern honey bees (Apis cerana). This mite has since become the most severe threat to A. mellifera world-wide. Despite this, some isolated A. mellifera populations are known to survive infestations by means of natural selection, largely by supressing mite reproduction, but the underlying mechanisms of this are poorly understood. Here, we show that a cost-effective social immunity mechanism has evolved rapidly and independently in four naturally V. destructor-surviving A. mellifera populations. Worker bees of all four 'surviving' populations uncapped/recapped worker brood cells more frequently and targeted mite-infested cells more effectively than workers in local susceptible colonies. Direct experiments confirmed the ability of uncapping/recapping to reduce mite reproductive success without sacrificing nestmates. Our results provide striking evidence that honey bees can overcome exotic parasites with simple qualitative and quantitative adaptive shifts in behaviour. Due to rapid, parallel evolution in four host populations this appears to be a key mechanism explaining survival of mite infested colonies.
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| 28. |
- Locke Grandér, Barbara, et al.
(författare)
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SLU redovisar tre studier om effekter på virusnivåer : Effekt på virusnivåer efter varroabekämpning
- 2016
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Ingår i: Bitidningen. - 0006-3886. ; 115, s. 20-23
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Tidskriftsartikel (populärvet., debatt m.m.)abstract
- Varroakvalstret (Varroa destructor) är ett av de största hoten mot biodling världen över. Utan behandling dör angripna bisamhällen vanligtvis inom några år, men inte på grund av själva kvalsterangreppet i sig utan av de virusinfektioner som sprids med och utvecklas effektivare på grund av kvalstren. Många olika slags virus har hittats hos honungsbin, och några av dem är starkt knutna till varroakvalstret.
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| 29. |
- Locke Grandér, Barbara, et al.
(författare)
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Virus Prevalence in Egg Samples Collected from Naturally Selected and Traditionally Managed Honey Bee Colonies across Europe
- 2022
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Ingår i: Viruses. - : MDPI AG. - 1999-4915. ; 14
-
Tidskriftsartikel (refereegranskat)abstract
- Monitoring virus infections can be an important selection tool in honey bee breeding. A recent study pointed towards an association between the virus-free status of eggs and an increased virus resistance to deformed wing virus (DWV) at the colony level. In this study, eggs from both naturally surviving and traditionally managed colonies from across Europe were screened for the prevalence of different viruses. Screenings were performed using the phenotyping protocol of the 'suppressed in ovo virus infection' trait but with qPCR instead of end-point PCR and a primer set that covers all DWV genotypes. Of the 213 screened samples, 109 were infected with DWV, 54 were infected with black queen cell virus (BQCV), 3 were infected with the sacbrood virus, and 2 were infected with the acute bee paralyses virus. It was demonstrated that incidences of the vertical transmission of DWV were more frequent in naturally surviving than in traditionally managed colonies, although the virus loads in the eggs remained the same. When comparing virus infections with queen age, older queens showed significantly lower infection loads of DWV in both traditionally managed and naturally surviving colonies, as well as reduced DWV infection frequencies in traditionally managed colonies. We determined that the detection frequencies of DWV and BQCV in honey bee eggs were lower in samples obtained in the spring than in those collected in the summer, indicating that vertical transmission may be lower in spring. Together, these patterns in vertical transmission show that honey bee queens have the potential to reduce the degree of vertical transmission over time.
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| 30. |
- Oddie, Melissa, et al.
(författare)
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Shift in virus composition in honeybees (Apis mellifera) following worldwide invasion by the parasitic mite and virus vector Varroa destructor
- 2024
-
Ingår i: Royal Society Open Science. - 2054-5703. ; 11
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Tidskriftsartikel (refereegranskat)abstract
- Invasive vectors can induce dramatic changes in disease epidemiology. While viral emergence following geographical range expansion of a vector is well known, the influence a vector can have at the level of the host's pathobiome is less well understood. Taking advantage of the formerly heterogeneous spatial distribution of the ectoparasitic mite Varroa destructor that acts as potent virus vector among honeybees Apis mellifera, we investigated the impact of its recent global spread on the viral community of honeybees in a retrospective study of historical samples. We hypothesized that the vector has had an effect on the epidemiology of several bee viruses, potentially altering their transmissibility and/or virulence, and consequently their prevalence, abundance, or both. To test this, we quantified the prevalence and loads of 14 viruses from honeybee samples collected in mite-free and mite-infested populations in four independent geographical regions. The presence of the mite dramatically increased the prevalence and load of deformed wing virus, a cause of unsustainably high colony losses. In addition, several other viruses became more prevalent or were found at higher load in mite-infested areas, including viruses not known to be actively varroa-transmitted, but which may increase opportunistically in varroa-parasitized bees.
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| 31. |
- Osterman, Julia, et al.
(författare)
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Clothianidin seed-treatment has no detectable negative impact on honeybee colonies and their pathogens
- 2019
-
Ingår i: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 10:1
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Tidskriftsartikel (refereegranskat)abstract
- Interactions between multiple stressors have been implicated in elevated honeybee colony losses. Here, we extend our landscape-scale study on the effects of placement at clothianidin seed-treated oilseed rape fields on honeybees with an additional year and new data on honeybee colony development, swarming, mortality, pathogens and immune gene expression. Clothianidin residues in pollen, nectar and honeybees were consistently higher at clothianidin-treated fields, with large differences between fields and years. We found large variations in colony development and microbial composition and no observable negative impact of placement at clothianidin-treated fields. Clothianidin treatment was associated with an increase in brood, adult bees and Gilliamella apicola (beneficial gut symbiont) and a decrease in Aphid lethal paralysis virus and Black queen cell virus - particularly in the second year. The results suggest that at colony level, honeybees are relatively robust to the effects of clothianidin in real-world agricultural landscapes, with moderate, natural disease pressure.
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| 32. |
- Ponnuvel, Kangayam M., et al.
(författare)
-
Genetic characterisation of an Iflavirus associated with a vomiting disease in the Indian tropical tasar silkworm, Antheraea mylitta
- 2022
-
Ingår i: Virus Research. - : Elsevier. - 0168-1702 .- 1872-7492. ; 311
-
Tidskriftsartikel (refereegranskat)abstract
- Antheraea mylitta, the Tropical tasar silkworm, is frequently affected by a vomiting disease called Virosis by sericulturists although not confirmed being of viral origin. Based on the symptoms and the disease pattern, the causal agent is however suspected to be a virus. The condition involves a series of characteristic and progressive symptoms that generally culminates in the death of the larva. The disease is common in autumn season (SepOct), with widespread distribution causing severe damage to the tasar silk industry. The leads for this study were obtained from a transcript identified in the EST database in a different study, which matched the positive strand of Iflavirus, an RNA virus known to infect insects. In the present study the genome of this novel Iflavirus was characterised and the full length of the genome was found to be 9728 nucleotides long encoding for a single large open reading frame (ORF) with flanking NTR regions at 5 ' and 3 ' ends and a natural poly A tail at the 3 ' end. The ORF encoded structural proteins at the N-terminal end and non-structural proteins at the C-terminal end with a predicted 2967 amino acid long polyprotein. The structural proteins consisted of 4 proteins (VP1-VP4) and the non-structural proteins consisted of helicase, RNA-dependent RNA polymerase and 3C-protease. The virus is found in various tissues (midgut, fatbody, trachea, Malpighian tubules and silk gland) and also has a vertical route of transmission, i.e., from gravid females to the offspring. Based on the available data, the virus is a new member of Iflaviridae for which we propose the name Antheraea mylitta Iflavirus (AmIV).
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| 33. |
- Rodrigues De Miranda, Joachim
(författare)
-
Analysis of reference gene stability after Israeli acute paralysis virus infection in bumblebees Bombus terrestris
- 2014
-
Ingår i: Journal of Invertebrate Pathology. - : Elsevier BV. - 0022-2011 .- 1096-0805. ; 115, s. 76-79
-
Tidskriftsartikel (refereegranskat)abstract
- To date, there are no validated internal reference genes for the normalization of RT-qPCR data from virus infection experiments with pollinating insects. In this study we evaluated the stability of five candidate internal reference genes: elongation factor-1 -alpha (ELF1 alpha), peptidylprolyl isomerase A (PPIA), 60S ribosomal protein L23 (RPL23), TATA-binding protein (TBP) and polyubiquitin (UBI), in relation to Israeli acute paralysis virus (IAPV) infection of Bombus terrestris. We investigated the stability of these genes: in whole bodies and individual body parts, as well as in whole bodies collected at different time intervals after infection with IAPV. Our data identified PPIA as the single, most-optimal internal reference gene and the combination of PPAI-RPL23-UBI as a fully-sufficient multiple internal reference genes set for IAPV infection experiments in B. terrestris. (C) 2013 Elsevier Inc. All rights reserved.
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| 34. |
- Rodrigues De Miranda, Joachim
(författare)
-
Bee Viruses: Routes of Infection in Hymenoptera
- 2020
-
Ingår i: Frontiers in Microbiology. - : Frontiers Media SA. - 1664-302X. ; 11
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Forskningsöversikt (refereegranskat)abstract
- Numerous studies have recently reported on the discovery of bee viruses in different arthropod species and their possible transmission routes, vastly increasing our understanding of these viruses and their distribution. Here, we review the current literature on the recent advances in understanding the transmission of viruses, both on the presence of bee viruses inApisand non-Apisbee species and on the discovery of previously unknown bee viruses. The natural transmission of bee viruses will be discussed among different bee species and other insects. Finally, the research potential ofin vivo(host organisms) andin vitro(cell lines) serial passages of bee viruses is discussed, from the perspective of the host-virus landscape changes and potential transmission routes for emerging bee virus infections.
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| 35. |
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| 36. |
- Rodrigues De Miranda, Joachim
(författare)
-
Bees under stress: sublethal doses of a neonicotinoid pesticide and pathogens interact to elevate honey bee mortality across the life cycle
- 2015
-
Ingår i: Environmental Microbiology. - : Wiley. - 1462-2912 .- 1462-2920. ; 17, s. 969-983
-
Tidskriftsartikel (refereegranskat)abstract
- Microbial pathogens are thought to have a profound impact on insect populations. Honey bees are suffering from elevated colony losses in the northern hemisphere possibly because of a variety of emergent microbial pathogens, with which pesticides may interact to exacerbate their impacts. To reveal such potential interactions, we administered at sublethal and field realistic doses one neonicotinoid pesticide (thiacloprid) and two common microbial pathogens, the invasive microsporidian Nosema ceranae and black queen cell virus (BQCV), individually to larval and adult honey bees in the laboratory. Through fully crossed experiments in which treatments were administered singly or in combination, we found an additive interaction between BQCV and thiacloprid on host larval survival likely because the pesticide significantly elevated viral loads. In adult bees, two synergistic interactions increased individual mortality: between N.ceranae and BQCV, and between N.ceranae and thiacloprid. The combination of two pathogens had a more profound effect on elevating adult mortality than N.ceranae plus thiacloprid. Common microbial pathogens appear to be major threats to honey bees, while sublethal doses of pesticide may enhance their deleterious effects on honey bee larvae and adults. It remains an open question as to whether these interactions can affect colony survival.
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| 37. |
- Rodrigues De Miranda, Joachim
(författare)
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Characterisation of the British honey bee metagenome
- 2018
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Ingår i: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 9
-
Tidskriftsartikel (refereegranskat)abstract
- The European honey bee (Apis mellifera) plays a major role in pollination and food production. Honey bee health is a complex product of the environment, host genetics and associated microbes (commensal, opportunistic and pathogenic). Improved understanding of these factors will help manage modern challenges to bee health. Here we used DNA sequencing to characterise the genomes and metagenomes of 19 honey bee colonies from across Britain. Low heterozygosity was observed in many Scottish colonies which had high similarity to the native dark bee. Colonies exhibited high diversity in composition and relative abundance of individual microbiome taxa. Most non-bee sequences were derived from known honey bee commensal bacteria or pathogens. However, DNA was also detected from additional fungal, protozoan and metazoan species. To classify cobionts lacking genomic information, we developed a novel network analysis approach for clustering orphan DNA contigs. Our analyses shed light on microbial communities associated with honey bees and demonstrate the power of high-throughput, directed metagenomics for identifying novel biological threats in agroecosystems.
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| 38. |
- Rodrigues De Miranda, Joachim, et al.
(författare)
-
Characterization of a Novel RNA Virus Discovered in the Autumnal Moth Epirrita autumnata in Sweden
- 2017
-
Ingår i: Viruses. - : MDPI AG. - 1999-4915. ; 9:8
-
Tidskriftsartikel (refereegranskat)abstract
- A novel, 10 kb RNA virus-tentatively named 'Abisko virus'-was discovered in the transcriptome data of a diseased autumnal moth (Epirrita autumnata) larva, as part of a search for the possible causes of the cyclical nature and mortality associated with geometrid moth dynamics and outbreaks in northern Fennoscandia. Abisko virus has a genome organization similar to that of the insect-infecting negeviruses, but phylogenetic and compositional bias analyses also reveal strong affiliations with plant-infecting viruses, such that both the primary host origin and taxonomic identity of the virus remain in doubt. In an extensive set of larval, pupal, and adult autumnal moth and winter moth (Operophtera brumata) outbreak samples, the virus was only detected in a few adult E. autumnata moths as well as the single larval transcriptome. The Abisko virus is therefore unlikely to be a factor in the Fennoscandia geometrid population dynamics.
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| 39. |
- Rodrigues De Miranda, Joachim
(författare)
-
Cryo-EM study of slow bee paralysis virus at low pH reveals iflavirus genome release mechanism
- 2017
-
Ingår i: Proceedings of the National Academy of Sciences of the United States of America. - : Proceedings of the National Academy of Sciences. - 0027-8424 .- 1091-6490. ; 114, s. 598-603
-
Tidskriftsartikel (refereegranskat)abstract
- Viruses from the family Iflaviridae are insect pathogens. Many of them, including slow bee paralysis virus (SBPV), cause lethal diseases in honeybees and bumblebees, resulting in agricultural losses. Iflaviruses have nonenveloped icosahedral virions containing single-stranded RNA genomes. However, their genome release mechanism is unknown. Here, we show that low pH promotes SBPV genome release, indicating that the virus may use endosomes to enter host cells. We used cryo-EM to study a heterogeneous population of SBPV virions at pH 5.5. We determined the structures of SBPV particles before and after genome release to resolutions of 3.3 and 3.4 angstrom, respectively. The capsids of SBPV virions in low pH are not expanded. Thus, SBPV does not appear to form "altered" particles with pores in their capsids before genome release, as is the case in many related picornaviruses. The egress of the genome from SBPV virions is associated with a loss of interpentamer contacts mediated by N-terminal arms of VP2 capsid proteins, which result in the expansion of the capsid. Pores that are 7 angstrom an diameter form around icosahedral threefold symmetry axes. We speculate that they serve as channels for the genome release. Our findings provide an atomic-level characterization of the genome release mechanism of iflaviruses.
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| 40. |
- Rodrigues De Miranda, Joachim
(författare)
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Deformed wing virus
- 2010
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Ingår i: Journal of Invertebrate Pathology. - : Elsevier BV. - 0022-2011 .- 1096-0805. ; 103, s. S48-S61
-
Forskningsöversikt (refereegranskat)abstract
- Deformed wing virus (DWV; Iflaviridae) is one of many viruses infecting honeybees and one of the most heavily investigated due to its close association with honeybee colony collapse induced by Varroa destructor. In the absence of V. destructor DWV infection does not result in visible symptoms or any apparent negative impact on host fitness. However, for reasons that are still not fully understood, the transmission of DWV by V. destructor to the developing pupae causes clinical symptoms, including pupal death and adult bees emerging with deformed wings, a bloated, shortened abdomen and discolouration. These bees are not viable and die soon after emergence. In this review we will summarize the historical and recent data on DWV and its relatives, covering the genetics, pathobiology, and transmission of this important viral honeybee pathogen, and discuss these within the wider theoretical concepts relating to the genetic variability and population structure of RNA viruses, the evolution of virulence and the development of disease symptoms. (C) 2009 Elsevier Inc. All rights reserved
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| 41. |
- Rodrigues De Miranda, Joachim
(författare)
-
Development and validation of a real-time two-step RT-qPCR TaqMan (R) assay for quantitation of Sacbrood virus (SBV) and its application to a field survey of symptomatic honey bee colonies
- 2014
-
Ingår i: Journal of Virological Methods. - : Elsevier BV. - 0166-0934 .- 1879-0984. ; 197, s. 7-13
-
Tidskriftsartikel (refereegranskat)abstract
- Sacbrood virus (SBV) is the causal agent of a disease of honey bee larvae, resulting in failure to pupate and causing death. The typical clinical symptom of SBV is an accumulation of SBV-rich fluid in swollen subcuticular pouches, forming the characteristic fluid-filled sac that gives its name to the disease. Outbreaks of the disease have been reported in different countries, affecting the development of the brood and causing losses in honey bee colonies. Today, few data are available on the SBV viral load in the case of overt disease in larvae, or for the behavioural changes of SBV-infected adult bees. A two-step real-time RT-PCR assay, based on TaqMan (R) technology using a fluorescent probe (FAM-TAMRA) was therefore developed to quantify Sacbrood virus in larvae, pupae and adult bees from symptomatic apiaries. This assay was first validated according to the recent XP-U47-600 standard issued by the French Standards Institute, where the reliability and the repeatability of the results and the performance of the assay were confirmed. The performance of the qPCR assay was validated over the 6 log range of the standard curve (i.e. from 10(2) to 10(8) copies per well) with a measurement uncertainty evaluated at 0.11 log(10). The detection and quantitation limits were established respectively at 50 copies and 100 copies of SBV genome, for a template volume of 5 mu l of cDNA. The RT-qPCR assay was applied during a French SBV outbreak in 2012 where larvae with typical SBV signs were collected, along with individuals without clinical signs. The SBV quantitation revealed that, in symptomatic larvae, the virus load was significantly higher than in samples without clinical signs. Combining quantitation with clinical data, a threshold of SBV viral load related to an overt disease was proposed (10(10) SBV genome copies per individual). (C) 2013 Elsevier B.V. All rights reserved.
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| 42. |
- Rodrigues De Miranda, Joachim
(författare)
-
Dicistroviridae
- 2017
-
Ingår i: ICTV Online Report. ; 10
-
Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 43. |
- Rodrigues de Miranda, Joachim
(författare)
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Distribution of infectious and parasitic agents among three sentinel bee species across European agricultural landscapes
- 2024
-
Ingår i: Scientific Reports. - 2045-2322. ; 14
-
Tidskriftsartikel (refereegranskat)abstract
- Infectious and parasitic agents (IPAs) and their associated diseases are major environmental stressors that jeopardize bee health, both alone and in interaction with other stressors. Their impact on pollinator communities can be assessed by studying multiple sentinel bee species. Here, we analysed the field exposure of three sentinel managed bee species (Apis mellifera, Bombus terrestris and Osmia bicornis) to 11 IPAs (six RNA viruses, two bacteria, three microsporidia). The sentinel bees were deployed at 128 sites in eight European countries adjacent to either oilseed rape fields or apple orchards during crop bloom. Adult bees of each species were sampled before their placement and after crop bloom. The IPAs were detected and quantified using a harmonised, high-throughput and semi-automatized qPCR workflow. We describe differences among bee species in IPA profiles (richness, diversity, detection frequencies, loads and their change upon field exposure, and exposure risk), with no clear patterns related to the country or focal crop. Our results suggest that the most frequent IPAs in adult bees are more appropriate for assessing the bees' IPA exposure risk. We also report positive correlations of IPA loads supporting the potential IPA transmission among sentinels, suggesting careful consideration should be taken when introducing managed pollinators in ecologically sensitive environments.
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| 44. |
- Rodrigues De Miranda, Joachim
(författare)
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Diversity and Global Distribution of Viruses of the Western Honey Bee, Apis mellifera
- 2020
-
Ingår i: Insects. - : MDPI AG. - 2075-4450. ; 11
-
Forskningsöversikt (refereegranskat)abstract
- In the past centuries, viruses have benefited from globalization to spread across the globe, infecting new host species and populations. A growing number of viruses have been documented in the western honey bee, Apis mellifera. Several of these contribute significantly to honey bee colony losses. This review synthetizes the knowledge of the diversity and distribution of honey-bee-infecting viruses, including recent data from high-throughput sequencing (HTS). After presenting the diversity of viruses and their corresponding symptoms, we surveyed the scientific literature for the prevalence of these pathogens across the globe. The geographical distribution shows that the most prevalent viruses (deformed wing virus, sacbrood virus, black queen cell virus and acute paralysis complex) are also the most widely distributed. We discuss the ecological drivers that influence the distribution of these pathogens in worldwide honey bee populations. Besides the natural transmission routes and the resulting temporal dynamics, global trade contributes to their dissemination. As recent evidence shows that these viruses are often multihost pathogens, their spread is a risk for both the beekeeping industry and the pollination services provided by managed and wild pollinators.
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| 45. |
- Rodrigues De Miranda, Joachim
(författare)
-
Effect of oral infection with Kashmir bee virus and Israeli acute paralysis virus on bumblebee (Bombus terrestris) reproductive success
- 2014
-
Ingår i: Journal of Invertebrate Pathology. - : Elsevier BV. - 0022-2011 .- 1096-0805. ; 121, s. 64-69
-
Tidskriftsartikel (refereegranskat)abstract
- Israeli acute paralysis virus (IAPV) together with Acute bee paralysis virus (ABPV) and Kashmir bee virus (KBV) constitute a complex of closely related dicistroviruses. They are infamous for their high mortality after injection in honeybees. These viruses have also been reported in non-Apis hymenopteran pollinators such as bumblebees, which got infected with IAPV when placed in the same greenhouse with IAPV infected honeybee hives. Here we orally infected Bombus terrestris workers with different doses of either IAPV or KBV viral particles. The success of the infection was established by analysis of the bumblebees after the impact studies: 50 days after infection. Doses of 0.5 x 10(7) and 1 x 10(7) virus particles per bee were infectious over this period, for IAPV and KBV respectively, while a dose of 0.5 x 10(6) IAPV particles per bee was not infectious. The impact of virus infection was studied in micro-colonies consisting of 5 bumblebees, one of which becomes a pseudo-queen which proceeds to lay unfertilized (drone) eggs. The impact parameters studied were: the establishment of a laying pseudo-queen, the timing of egg-laying, the number of drones produced, the weight of these drones and worker mortality. In this setup KBV infection resulted in a significant slower colony startup and offspring production, while only the latter can be reported for IAPV. Neither virus increased worker mortality, at the oral doses used. We recommend further studies on how these viruses transmit between different pollinator species. It is also vital to understand how viral prevalence can affect wild bee populations because disturbance of the natural host-virus association may deteriorate the already critically endangered status of many bumblebee species. (C) 2014 Elsevier Inc. All rights reserved.
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| 46. |
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| 47. |
- Rodrigues De Miranda, Joachim, et al.
(författare)
-
Genetic Characterization of a Novel Iflavirus Associated with Vomiting Disease in the Chinese Oak Silkmoth Antheraea pernyi
- 2014
-
Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 9
-
Tidskriftsartikel (refereegranskat)abstract
- Larvae of the Chinese oak silkmoth (Antheraea pernyi) are often affected by AVD (A. pernyi vomiting disease), whose causative agent has long been suspected to be a virus. In an unrelated project we discovered a novel positive sense single-stranded RNA virus that could reproduce AVD symptoms upon injection into healthy A. pernyi larvae. The genome of this virus is 10,163 nucleotides long, has a natural poly-A tail, and contains a single, large open reading frame flanked at the 5' and 3' ends by untranslated regions containing putative structural elements for replication and translation of the virus genome. The open reading frame is predicted to encode a 3036 amino acid polyprotein with four viral structural proteins (VP1-VP4) located in the N-terminal end and the non-structural proteins, including a helicase, RNA-dependent RNA polymerase and 3C-protease, located in the C-terminal end of the polyprotein. Putative 3C-protease and autolytic cleavage sites were identified for processing the polyprotein into functional units. The genome organization, amino acid sequence and phylogenetic analyses suggest that the virus is a novel species of the genus Iflavirus, with the proposed name of Antheraea pernyi Iflavirus (ApIV).
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| 48. |
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| 49. |
- Rodrigues De Miranda, Joachim, et al.
(författare)
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Genome Characterization, Prevalence and Distribution of a Macula-Like Virus from Apis mellifera and Varroa destructor
- 2015
-
Ingår i: Viruses. - : MDPI AG. - 1999-4915. ; 7, s. 3586-3602
-
Tidskriftsartikel (refereegranskat)abstract
- Around 14 distinct virus species-complexes have been detected in honeybees, each with one or more strains or sub-species. Here we present the initial characterization of an entirely new virus species-complex discovered in honeybee (Apis mellifera L.) and varroa mite (Varroa destructor) samples from Europe and the USA. The virus has a naturally poly-adenylated RNA genome of about 6500 nucleotides with a genome organization and sequence similar to the Tymoviridae (Tymovirales; Tymoviridae), a predominantly plant-infecting virus family. Literature and laboratory analyses indicated that the virus had not previously been described. The virus is very common in French apiaries, mirroring the results from an extensive Belgian survey, but could not be detected in equally-extensive Swedish and Norwegian bee disease surveys. The virus appears to be closely linked to varroa, with the highest prevalence found in varroa samples and a clear seasonal distribution peaking in autumn, coinciding with the natural varroa population development. Sub-genomic RNA analyses show that bees are definite hosts, while varroa is a possible host and likely vector. The tentative name of Bee Macula-like virus (BeeMLV) is therefore proposed. A second, distantly related Tymoviridae-like virus was also discovered in varroa transcriptomes, tentatively named Varroa Tymo-like virus (VTLV).
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| 50. |
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