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Becchimanzi A, Nicoletti R. Aspergillus-bees: A dynamic symbiotic association. Front Microbiol 2022; 13:968963. [PMID: 36160228 PMCID: PMC9489833 DOI: 10.3389/fmicb.2022.968963] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Accepted: 08/22/2022] [Indexed: 11/24/2022] Open
Abstract
Besides representing one of the most relevant threats of fungal origin to human and animal health, the genus Aspergillus includes opportunistic pathogens which may infect bees (Hymenoptera, Apoidea) in all developmental stages. At least 30 different species of Aspergillus have been isolated from managed and wild bees. Some efficient behavioral responses (e.g., diseased brood removal) exerted by bees negatively affect the chance to diagnose the pathology, and may contribute to the underestimation of aspergillosis importance in beekeeping. On the other hand, bee immune responses may be affected by biotic and abiotic stresses and suffer from the loose co-evolutionary relationships with Aspergillus pathogenic strains. However, if not pathogenic, these hive mycobiota components can prove to be beneficial to bees, by affecting the interaction with other pathogens and parasites and by detoxifying xenobiotics. The pathogenic aptitude of Aspergillus spp. likely derives from the combined action of toxins and hydrolytic enzymes, whose effects on bees have been largely overlooked until recently. Variation in the production of these virulence factors has been observed among strains, even belonging to the same species. Toxigenic and non-toxigenic strains/species may co-exist in a homeostatic equilibrium which is susceptible to be perturbed by several external factors, leading to mutualistic/antagonistic switch in the relationships between Aspergillus and bees.
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Affiliation(s)
- Andrea Becchimanzi
- Department of Agricultural Sciences, University of Naples Federico II, Portici, Italy
- *Correspondence: Andrea Becchimanzi,
| | - Rosario Nicoletti
- Department of Agricultural Sciences, University of Naples Federico II, Portici, Italy
- Council for Agricultural Research and Economics, Research Centre for Olive, Fruit and Citrus Crops, Caserta, Italy
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2
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Aguero CM, Eyer P, Martin JS, Bulmer MS, Vargo EL. Natural variation in colony inbreeding does not influence susceptibility to a fungal pathogen in a termite. Ecol Evol 2021; 11:3072-3083. [PMID: 33841768 PMCID: PMC8019025 DOI: 10.1002/ece3.7233] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Revised: 01/08/2021] [Accepted: 01/15/2021] [Indexed: 01/26/2023] Open
Abstract
Reduced genetic diversity through inbreeding can negatively affect pathogen resistance. This relationship becomes more complicated in social species, such as social insects, since the chance of disease transmission increases with the frequency of interactions among individuals. However, social insects may benefit from social immunity, whereby individual physiological defenses may be bolstered by collective-level immune responses, such as grooming or sharing of antimicrobial substance through trophallaxis. We set out to determine whether differences in genetic diversity between colonies of the subterranean termite, Reticulitermes flavipes, accounts for colony survival against pathogens. We sampled colonies throughout the United States (Texas, North Carolina, Maryland, and Massachusetts) and determined the level of inbreeding of each colony. To assess whether genetically diverse colonies were better able to survive exposure to diverse pathogens, we challenged groups of termite workers with two strains of a pathogenic fungus, one local strain present in the soil surrounding sampled colonies and another naïve strain, collected outside the range of this species. We found natural variation in the level of inbreeding between colonies, but this variation did not explain differences in susceptibility to either pathogen. Although the naïve strain was found to be more hazardous than the local strain, colony resistance was correlated between two strains, meaning that colonies had either relatively high or low susceptibility to both strains regardless of their inbreeding coefficient. Overall, our findings may reflect differential virulence between the strains, immune priming of the colonies via prior exposure to the local strain, or a coevolved resistance toward this strain. They also suggest that colony survival may rely more upon additional factors, such as different behavioral response thresholds or the influence of a specific genetic background, rather than the overall genetic diversity of the colony.
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Affiliation(s)
- Carlos M. Aguero
- Department of EntomologyTexas A&M UniversityCollege StationTXUSA
| | | | - Jason S. Martin
- Department of Biological SciencesTowson UniversityTowsonMDUSA
| | - Mark S. Bulmer
- Department of Biological SciencesTowson UniversityTowsonMDUSA
| | - Edward L. Vargo
- Department of EntomologyTexas A&M UniversityCollege StationTXUSA
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3
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Aguero CM, Eyer PA, Vargo EL. Increased genetic diversity from colony merging in termites does not improve survival against a fungal pathogen. Sci Rep 2020; 10:4212. [PMID: 32144325 PMCID: PMC7060273 DOI: 10.1038/s41598-020-61278-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Accepted: 02/24/2020] [Indexed: 12/26/2022] Open
Abstract
In some species of social insects the increased genetic diversity from having multiple breeders in a colony has been shown to improve pathogen resistance. Termite species typically found colonies from single mated pairs and therefore may lack the flexibility to buffer pathogen pressure with increased genetic diversity by varying the initial number of reproductives. However, they can later increase group diversity through colony merging, resulting in a genetically diverse, yet cohesive, workforce. In this study, we investigate whether the increased group diversity from colony fusion benefits social immunity in the subterranean termite Reticulitermes flavipes. We confirm previous findings that colonies of R. flavipes will readily merge and we show that workers will equally groom nestmates and non-nestmates after merging. Despite this, the survival of these merged colonies was not improved after exposure to a fungal pathogen, but instead leveled to that of the more susceptible or the more resistant colony. Our study brings little support to the hypothesis that colony fusion may improve immunity through an increase of genetic diversity in R. flavipes. Instead, we find that following exposure to a lethal pathogen, one colony is heavily influential to the entire group's survival after merging.
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Affiliation(s)
- Carlos M Aguero
- Department of Entomology, 2143 TAMU, Texas A&M University, College Station, Texas, 77843-2143, USA.
| | - Pierre-André Eyer
- Department of Entomology, 2143 TAMU, Texas A&M University, College Station, Texas, 77843-2143, USA
| | - Edward L Vargo
- Department of Entomology, 2143 TAMU, Texas A&M University, College Station, Texas, 77843-2143, USA
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4
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Lewkowski O, Erler S. Virulence of Melissococcus plutonius and secondary invaders associated with European foulbrood disease of the honey bee. Microbiologyopen 2018; 8:e00649. [PMID: 29799173 PMCID: PMC6436434 DOI: 10.1002/mbo3.649] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2018] [Revised: 03/16/2018] [Accepted: 04/09/2018] [Indexed: 11/29/2022] Open
Abstract
European foulbrood is a globally distributed brood disease affecting honey bees. It may lead to lethal infections of larvae and, in severe cases, even to colony collapse. Lately, a profound genetic and phenotypic diversity was documented for the causative agent Melissococcus plutonius. However, experimental work on the impact of diverse M. plutonius strains on hosts with different genetic background is completely lacking and the role of secondary invaders is poorly understood. Here, we address these issues and elucidate the impact and interaction of both host and pathogen on one another. Moreover, we try to unravel the role of secondary bacterial invasions in foulbrood‐diseased larvae. We employed in vitro infections with honey bee larvae from queens with different genetic background and three different M. plutonius strains. Larvae infection experiments showed host‐dependent survival dynamics although M. plutonius strain 49.3 consistently had the highest virulence. This pattern was also reflected in significantly reduced weights of 49.3 strain‐infected larvae compared to the other treatments. No difference was found in groups additionally inoculated with a secondary invader (Enterococcus faecalis or Paenibacillus alvei) neither in terms of larval survival nor weight. These results suggest that host background contributes markedly to the course of the disease but virulence is mainly dependent on pathogen genotype. Secondary invaders following a M. plutonius infection do not increase disease lethality and therefore may just be a colonization of weakened and immunodeficient, or dead larvae.
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Affiliation(s)
- Oleg Lewkowski
- Institute of Biology, Molecular Ecology, Martin-Luther-University Halle-Wittenberg, Halle (Saale), Germany
| | - Silvio Erler
- Institute of Biology, Molecular Ecology, Martin-Luther-University Halle-Wittenberg, Halle (Saale), Germany
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5
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Evison SE, Jensen AB. The biology and prevalence of fungal diseases in managed and wild bees. CURRENT OPINION IN INSECT SCIENCE 2018; 26:105-113. [PMID: 29764649 DOI: 10.1016/j.cois.2018.02.010] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2017] [Revised: 12/15/2017] [Accepted: 02/02/2018] [Indexed: 06/08/2023]
Abstract
Managed and wild bees, whether solitary or social have a plethora of microbial associations that vary in their influence on the health of the bees. In this review, we summarise our current knowledge of aspects of the biology and ecology of bee associated fungi. The biology of bees that fungi are associated with are described, and the likely influences on fungal transmission are discussed. There is a clear disparity in research on fungi associated with managed compared to wild bees, leaving gaps in our understanding of fungal pathogen epidemiology. Translocation of bees to meet global pollination needs will increase exposure of bees to exotic pathogens. Thus, filling these gaps is an important step towards mitigating the impact of fungal diseases in bees.
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Affiliation(s)
- Sophie Ef Evison
- Animal and Plant Sciences, University of Sheffield, Alfred Denny Building, Western Bank, Sheffield S10 2TN, UK.
| | - Annette B Jensen
- Department of Plant and Environmental Sciences, University of Copenhagen, Thorvaldsensvej 40, 1871 Frederiksberg C., Denmark
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6
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Frenken T, Alacid E, Berger SA, Bourne EC, Gerphagnon M, Grossart HP, Gsell AS, Ibelings BW, Kagami M, Küpper FC, Letcher PM, Loyau A, Miki T, Nejstgaard JC, Rasconi S, Reñé A, Rohrlack T, Rojas-Jimenez K, Schmeller DS, Scholz B, Seto K, Sime-Ngando T, Sukenik A, Van de Waal DB, Van den Wyngaert S, Van Donk E, Wolinska J, Wurzbacher C, Agha R. Integrating chytrid fungal parasites into plankton ecology: research gaps and needs. Environ Microbiol 2017; 19:3802-3822. [DOI: 10.1111/1462-2920.13827] [Citation(s) in RCA: 120] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Revised: 06/09/2017] [Accepted: 06/10/2017] [Indexed: 01/19/2023]
Affiliation(s)
- Thijs Frenken
- Department of Aquatic Ecology; Netherlands Institute of Ecology (NIOO-KNAW), Droevendaalsesteeg 10; Wageningen PB 6708 The Netherlands
| | - Elisabet Alacid
- Departament de Biologia Marina i Oceanografia; Institut de Ciències del Mar (CSIC), Pg. Marítim de la Barceloneta, 37-49; Barcelona 08003 Spain
| | - Stella A. Berger
- Department of Experimental Limnology; Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB), Alte Fischerhuette 2; Stechlin D-16775 Germany
| | - Elizabeth C. Bourne
- Berlin Center for Genomics in Biodiversity Research, Königin-Luise-Straβe 6-8; Berlin D-14195 Germany
- Department of Ecosystem Research; Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB), Müggelseedamm 301; Berlin 12587 Germany
| | - Mélanie Gerphagnon
- Department of Ecosystem Research; Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB), Müggelseedamm 301; Berlin 12587 Germany
| | - Hans-Peter Grossart
- Department of Experimental Limnology; Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB), Alte Fischerhuette 2; Stechlin D-16775 Germany
- Institute for Biochemistry and Biology, Potsdam University, Maulbeerallee 2; Potsdam D-14476 Germany
| | - Alena S. Gsell
- Department of Aquatic Ecology; Netherlands Institute of Ecology (NIOO-KNAW), Droevendaalsesteeg 10; Wageningen PB 6708 The Netherlands
| | - Bas W. Ibelings
- Department F.-A. Forel for Environmental and Aquatic Sciences & Institute for Environmental Sciences; University of Geneva, 66 Boulevard Carl Vogt; Geneva 4 CH 1211 Switzerland
| | - Maiko Kagami
- Department of Environmental Sciences, Faculty of Science; Toho University, 2-2-1, Miyama; Funabashi Chiba 274-8510 Japan
| | - Frithjof C. Küpper
- Oceanlab, University of Aberdeen, Main Street; Newburgh Scotland AB41 6AA UK
| | - Peter M. Letcher
- Department of Biological Sciences; The University of Alabama, 300 Hackberry Lane; Tuscaloosa AL 35487 USA
| | - Adeline Loyau
- Department of System Ecotoxicology; Helmholtz Center for Environmental Research - UFZ, Permoserstrasse 15; 04318 Leipzig Germany
- Department of Conservation Biology; Helmholtz Center for Environmental Research - UFZ, Permoserstrasse 15; Leipzig 04318 Germany
- ECOLAB, Université de Toulouse, CNRS, INPT, UPS; Toulouse France
| | - Takeshi Miki
- Institute of Oceanography; National Taiwan University, No.1 Section 4, Roosevelt Road; Taipei 10617 Taiwan
- Research Center for Environmental Changes; Academia Sinica, No.128 Section 2, Academia Road, Nankang; Taipei 11529 Taiwan
| | - Jens C. Nejstgaard
- Department of Experimental Limnology; Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB), Alte Fischerhuette 2; Stechlin D-16775 Germany
| | - Serena Rasconi
- WasserCluster Lunz - Biological Station; Inter-University Centre for Aquatic Ecosystem Research, A-3293 Lunz am See; Austria
| | - Albert Reñé
- Departament de Biologia Marina i Oceanografia; Institut de Ciències del Mar (CSIC), Pg. Marítim de la Barceloneta, 37-49; Barcelona 08003 Spain
| | - Thomas Rohrlack
- Faculty of Environmental Sciences and Natural Resource Management; Norwegian University of Life Sciences, P.O. Box 5003, NO-1432, Ås; Norway
| | - Keilor Rojas-Jimenez
- Department of Experimental Limnology; Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB), Alte Fischerhuette 2; Stechlin D-16775 Germany
- Universidad Latina de Costa Rica, Campus San Pedro, Apdo; San Jose 10138-1000 Costa Rica
| | - Dirk S. Schmeller
- Department of Conservation Biology; Helmholtz Center for Environmental Research - UFZ, Permoserstrasse 15; Leipzig 04318 Germany
- ECOLAB, Université de Toulouse, CNRS, INPT, UPS; Toulouse France
| | - Bettina Scholz
- BioPol ehf, Einbúastig 2, Skagaströnd 545; Iceland
- Faculty of Natural Resource Sciences; University of Akureyri, Borgir v. Nordurslod; Akureyri IS 600 Iceland
| | - Kensuke Seto
- Department of Environmental Sciences, Faculty of Science; Toho University, 2-2-1, Miyama; Funabashi Chiba 274-8510 Japan
- Sugadaira Montane Research Center; University of Tsukuba, 1278-294, Sugadaira-Kogen; Ueda, Nagano, 386-2204 Japan
| | - Télesphore Sime-Ngando
- Université Clermont Auvergne, UMR CNRS 6023 LMGE, Laboratoire Microorganismes: Génome et Environnement (LMGE); Campus Universitaire des Cézeaux, Impasse Amélie Murat 1, CS 60026, Aubière, 63178 France
| | - Assaf Sukenik
- Kinneret Limnological Laboratory; Israel Oceanographic & Limnological Research, P.O.Box 447; Migdal, 14950 Israel
| | - Dedmer B. Van de Waal
- Department of Aquatic Ecology; Netherlands Institute of Ecology (NIOO-KNAW), Droevendaalsesteeg 10; Wageningen PB 6708 The Netherlands
| | - Silke Van den Wyngaert
- Department of Experimental Limnology; Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB), Alte Fischerhuette 2; Stechlin D-16775 Germany
| | - Ellen Van Donk
- Department of Aquatic Ecology; Netherlands Institute of Ecology (NIOO-KNAW), Droevendaalsesteeg 10; Wageningen PB 6708 The Netherlands
- Department of Biology; University of Utrecht, Padualaan 8; Utrecht TB 3508 The Netherlands
| | - Justyna Wolinska
- Department of Ecosystem Research; Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB), Müggelseedamm 301; Berlin 12587 Germany
- Institute of Biology, Freie Universität Berlin, Königin-Luise-Straβe 1-3; Berlin, 14195 Germany
| | - Christian Wurzbacher
- Department of Biological and Environmental Sciences; University of Gothenburg, Box 461; Göteborg, 405 30 Sweden
- Gothenburg Global Biodiversity Centre, Box 461; Göteborg, SE-405 30 Sweden
| | - Ramsy Agha
- Department of Ecosystem Research; Leibniz-Institute of Freshwater Ecology and Inland Fisheries (IGB), Müggelseedamm 301; Berlin 12587 Germany
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7
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Liu X, Wang L, Xiang M. Chapter 25 Coevolution of Fungi and Invertebrates. Mycology 2017. [DOI: 10.1201/9781315119496-26] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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8
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Simone-Finstrom M. Social Immunity and the Superorganism: Behavioral Defenses Protecting Honey Bee Colonies from Pathogens and Parasites. ACTA ACUST UNITED AC 2017. [DOI: 10.1080/0005772x.2017.1307800] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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9
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Higher immunocompetence is associated with higher genetic diversity in feral honey bee colonies (Apis mellifera). CONSERV GENET 2017. [DOI: 10.1007/s10592-017-0942-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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10
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Schmid-Hempel P. Parasites and Their Social Hosts. Trends Parasitol 2017; 33:453-462. [PMID: 28169113 DOI: 10.1016/j.pt.2017.01.003] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Revised: 01/04/2017] [Accepted: 01/05/2017] [Indexed: 11/16/2022]
Abstract
The study of parasitism in socially living organisms shows that social group size correlates with the risk of infection, but group structure - and thus differences in contact networks - is generally more important. Also, genetic makeup or environmental conditions have effects. 'Social immunity' focuses on defence against parasites that are particular to social living. Recently, the role of socially transmitted microbiota for defence has become a focus, too. But whether and how parasites adapt to social organisms - beyond adaptation to solitary hosts - is poorly understood. Genomic and proteomic methods, as well as network analysis, will be tools that hold promise for many unsolved questions, but to expand our concepts in the first place is a much needed agenda.
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Affiliation(s)
- Paul Schmid-Hempel
- ETH Zürich, Institute of Integrative Biology (IBZ), ETH-Zentrum CHN, Universitätsstrasse 16, CH-8092 Zürich, Switzerland.
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11
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Simone-Finstrom M, Walz M, Tarpy DR. Genetic diversity confers colony-level benefits due to individual immunity. Biol Lett 2016; 12:20151007. [PMID: 26961896 DOI: 10.1098/rsbl.2015.1007] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Several costs and benefits arise as a consequence of eusociality and group-living. With increasing group size, spread of disease among nest-mates poses selective pressure on both individual immunity and group-level mechanisms of disease resistance (social immunity). Another factor known to influence colony-level expression of disease is intracolony genetic diversity, which in honeybees (Apis mellifera) is a direct function of the number of mates of the queen. Colonies headed by queens with higher mating numbers have less variable infections of decreased intensity, though the underlying mechanisms remain unclear. By pathogen-challenging larvae in vitro, we decoupled larval immune response from mechanisms of social immunity. Our results show that baseline immunity and degree of immune response do not vary with genetic diversity. However, intracolony variance in antimicrobial peptide production after pathogen challenge decreases with increasing genetic diversity. This reduction in variability of the larval immune response could drive the mitigation of disease observed in genetically diverse colonies.
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Affiliation(s)
- Michael Simone-Finstrom
- Department of Entomology, North Carolina State University, Raleigh, NC 27695-7613, USA W. M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, NC 27695-7613, USA
| | - Megan Walz
- Department of Entomology, North Carolina State University, Raleigh, NC 27695-7613, USA
| | - David R Tarpy
- Department of Entomology, North Carolina State University, Raleigh, NC 27695-7613, USA W. M. Keck Center for Behavioral Biology, North Carolina State University, Raleigh, NC 27695-7613, USA
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12
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13
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Thrall PH, Barrett LG, Dodds PN, Burdon JJ. Epidemiological and Evolutionary Outcomes in Gene-for-Gene and Matching Allele Models. FRONTIERS IN PLANT SCIENCE 2016; 6:1084. [PMID: 26779200 PMCID: PMC4703789 DOI: 10.3389/fpls.2015.01084] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Accepted: 11/19/2015] [Indexed: 05/30/2023]
Abstract
Gene-for-gene (GFG) and matching-allele (MA) models are qualitatively different paradigms for describing the outcome of genetic interactions between hosts and pathogens. The GFG paradigm was largely built on the foundations of Flor's early work on the flax-flax rust interaction and is based on the concept of genetic recognition leading to incompatible disease outcomes, typical of host immune recognition. In contrast, the MA model is based on the assumption that genetic recognition leads to compatible interactions, which can result when pathogens require specific host factors to cause infection. Results from classical MA and GFG models have led to important predictions regarding various coevolutionary phenomena, including the role of fitness costs associated with resistance and infectivity, the distribution of resistance genes in wild populations, patterns of local adaptation and the evolution and maintenance of sexual reproduction. Empirical evidence (which we review briefly here), particularly from recent molecular advances in understanding of the mechanisms that determine the outcome of host-pathogen encounters, suggests considerable variation in specific details of the functioning of interactions between hosts and pathogens, which may contain elements of both models. In this regard, GFG and MA scenarios likely represent endpoints of a continuum of potentially more complex interactions that occur in nature. Increasingly, this has been recognized in theoretical studies of coevolutionary processes in plant host-pathogen and animal host-parasite associations (e.g., departures from strict GFG/MA assumptions, diploid genetics, multi-step infection processes). However, few studies have explored how different genetic assumptions about host resistance and pathogen infectivity might impact on disease epidemiology or pathogen persistence within and among populations. Here, we use spatially explicit simulations of the basic MA and GFG scenarios to highlight qualitative differences between these scenarios with regard to patterns of disease and impacts on host demography. Given that such impacts drive evolutionary trajectories, future theoretical advances that aim to capture more complex genetic scenarios should explicitly address the interaction between epidemiology and different models of host-pathogen interaction genetics.
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14
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Heneberg P, Bizos J, Čmoková A, Kolařík M, Astapenková A, Bogusch P. Assemblage of filamentous fungi associated with aculeate hymenopteran brood in reed galls. J Invertebr Pathol 2015; 133:95-106. [PMID: 26706117 DOI: 10.1016/j.jip.2015.12.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2015] [Revised: 12/07/2015] [Accepted: 12/14/2015] [Indexed: 01/17/2023]
Abstract
Monotypic stands of common reed and the reed-gall-associated insect assemblages are distributed worldwide. However, fungi associated with these assemblages have not been characterized in detail. Here we examined 5200 individuals (12 species) of immature aculeate hymenopterans or their parasitoids collected at 34 sampling sites in Central Europe. We noticed fungal outgrowth on exoskeletons of 83 (1.60%) larvae and pupae. The most common host was eudominant Pemphredon fabricii. However, the less abundant aculeate hymenopteran reed gall inquilines were infected at higher prevalence, these included Trypoxylon deceptorium, Trypoxylon minus, Hoplitis leucomelana and Hylaeus moricei (all considered new host records). We identified three fungal species, Penicillium buchwaldii (72% of cases), Aspergillus pseudoglaucus (22%) and Penicillium quebecense (6%). When multibrooded nests were affected, only a part of individuals was infected in 62% of cases. The sampling site-specific infection rate reached up to 13%, thus fungal infections should be considered an important variable driving the abundance of gall inquilines. Infections of generalist host species were more frequent than those of reed gall specialists, suggesting that suboptimal conditions decreased the immunocompetence of non-specialized species, which only occasionally nest in reed galls and feed in reed beds.
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Affiliation(s)
- Petr Heneberg
- Charles University in Prague, Third Faculty of Medicine, Prague, Czech Republic.
| | - Jiří Bizos
- Charles University in Prague, Third Faculty of Medicine, Prague, Czech Republic
| | - Adéla Čmoková
- Academy of Sciences of the Czech Republic, Institute of Microbiology, Laboratory of Fungal Genetics and Metabolism, Prague, Czech Republic; Charles University in Prague, Faculty of Science, Department of Botany, Prague, Czech Republic
| | - Miroslav Kolařík
- Academy of Sciences of the Czech Republic, Institute of Microbiology, Laboratory of Fungal Genetics and Metabolism, Prague, Czech Republic; Charles University in Prague, Faculty of Science, Department of Botany, Prague, Czech Republic
| | - Alena Astapenková
- University of Hradec Králové, Faculty of Science, Hradec Králové, Czech Republic
| | - Petr Bogusch
- University of Hradec Králové, Faculty of Science, Hradec Králové, Czech Republic
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15
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Evison SE. Chalkbrood: epidemiological perspectives from the host-parasite relationship. CURRENT OPINION IN INSECT SCIENCE 2015; 10:65-70. [PMID: 29588016 DOI: 10.1016/j.cois.2015.04.015] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2015] [Revised: 04/23/2015] [Accepted: 04/28/2015] [Indexed: 06/08/2023]
Abstract
Chalkbrood is a fungal brood disease of the honey bee, Apis mellifera, caused by the parasite Ascosphaera apis. Considered as a stress-related disease, the severity of chalkbrood outbreaks depend on a multitude of interacting factors. The specific relationship between host and parasite in this disease is interesting because the parasite is both heterothallic and semelparous. Recent studies highlight that this specific host-parasite relationship is influenced by factors such as interactions with other parasite strains or species, and environmental perturbations. To understand how to protect pollinators most effectively, it is crucial that future research takes a more ecologically relevant approach by studying the basic biology of the host-parasite relationship in the context of the multi-factorial processes that influence it.
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Affiliation(s)
- Sophie Ef Evison
- Animal and Plant Sciences, University of Sheffield, Alfred Denny Building, Western Bank, Sheffield S10 2TN, UK.
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16
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Evison SEF, Foley K, Jensen AB, Hughes WOH. Genetic diversity, virulence and fitness evolution in an obligate fungal parasite of bees. J Evol Biol 2015; 28:179-88. [PMID: 25407685 DOI: 10.1111/jeb.12555] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2014] [Revised: 11/15/2014] [Accepted: 11/17/2014] [Indexed: 01/15/2023]
Abstract
Within-host competition is predicted to drive the evolution of virulence in parasites, but the precise outcomes of such interactions are often unpredictable due to many factors including the biology of the host and the parasite, stochastic events and co-evolutionary interactions. Here, we use a serial passage experiment (SPE) with three strains of a heterothallic fungal parasite (Ascosphaera apis) of the Honey bee (Apis mellifera) to assess how evolving under increasing competitive pressure affects parasite virulence and fitness evolution. The results show an increase in virulence after successive generations of selection and consequently faster production of spores. This faster sporulation, however, did not translate into more spores being produced during this longer window of sporulation; rather, it appeared to induce a loss of fitness in terms of total spore production. There was no evidence to suggest that a greater diversity of competing strains was a driver of this increased virulence and subsequent fitness cost, but rather that strain-specific competitive interactions influenced the evolutionary outcomes of mixed infections. It is possible that the parasite may have evolved to avoid competition with multiple strains because of its heterothallic mode of reproduction, which highlights the importance of understanding parasite biology when predicting disease dynamics.
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Affiliation(s)
- S E F Evison
- Faculty of Biological Sciences, School of Biology, University of Leeds, Leeds, UK
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Graystock P, Goulson D, Hughes WO. The relationship between managed bees and the prevalence of parasites in bumblebees. PeerJ 2014; 2:e522. [PMID: 25165632 PMCID: PMC4137657 DOI: 10.7717/peerj.522] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2014] [Accepted: 07/24/2014] [Indexed: 11/24/2022] Open
Abstract
Honey bees and, more recently, bumblebees have been domesticated and are now managed commercially primarily for crop pollination, mixing with wild pollinators during foraging on shared flower resources. There is mounting evidence that managed honey bees or commercially produced bumblebees may affect the health of wild pollinators such as bumblebees by increasing competition for resources and the prevalence of parasites in wild bees. Here we screened 764 bumblebees from around five greenhouses that either used commercially produced bumblebees or did not, as well as bumblebees from 10 colonies placed at two sites either close to or far from a honey bee apiary, for the parasites Apicystis bombi, Crithidia bombi, Nosema bombi, N. ceranae, N. apis and deformed wing virus. We found that A. bombi and C. bombi were more prevalent around greenhouses using commercially produced bumblebees, while C. bombi was 18% more prevalent in bumblebees at the site near to the honey bee apiary than those at the site far from the apiary. Whilst these results are from only a limited number of sites, they support previous reports of parasite spillover from commercially produced bumblebees to wild bumblebees, and suggest that the impact of stress from competing with managed bees or the vectoring of parasites by them on parasite prevalence in wild bees needs further investigation. It appears increasingly likely that the use of managed bees comes at a cost of increased parasites in wild bumblebees, which is not only a concern for bumblebee conservation, but which may impact other pollinators as well.
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Affiliation(s)
| | - Dave Goulson
- School of Life Sciences, University of Sussex, Brighton, UK
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18
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Martinez AJ, Ritter SG, Doremus MR, Russell JA, Oliver KM. Aphid-encoded variability in susceptibility to a parasitoid. BMC Evol Biol 2014; 14:127. [PMID: 24916045 PMCID: PMC4057601 DOI: 10.1186/1471-2148-14-127] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2014] [Accepted: 05/27/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Many animals exhibit variation in resistance to specific natural enemies. Such variation may be encoded in their genomes or derived from infection with protective symbionts. The pea aphid, Acyrthosiphon pisum, for example, exhibits tremendous variation in susceptibility to a common natural enemy, the parasitic wasp Aphidius ervi. Pea aphids are often infected with the heritable bacterial symbiont, Hamiltonella defensa, which confers partial to complete resistance against this parasitoid depending on bacterial strain and associated bacteriophages. That previous studies found that pea aphids without H. defensa (or other symbionts) were generally susceptible to parasitism, together with observations of a limited encapsulation response, suggested that pea aphids largely rely on infection with H. defensa for protection against parasitoids. However, the limited number of uninfected clones previously examined, and our recent report of two symbiont-free resistant clones, led us to explicitly examine aphid-encoded variability in resistance to parasitoids. RESULTS After rigorous screening for known and unknown symbionts, and microsatellite genotyping to confirm clonal identity, we conducted parasitism assays using fifteen clonal pea aphid lines. We recovered significant variability in aphid-encoded resistance, with variation levels comparable to that contributed by H. defensa. Because resistance can be costly, we also measured aphid longevity and cumulative fecundity of the most and least resistant aphid lines under permissive conditions, but found no trade-offs between higher resistance and these fitness parameters. CONCLUSIONS These results indicate that pea aphid resistance to A. ervi is more complex than previously appreciated, and that aphids employ multiple tactics to aid in their defense. While we did not detect a tradeoff, these may become apparent under stressful conditions or when resistant and susceptible aphids are in direct competition. Understanding sources and amounts of variation in resistance to natural enemies is necessary to understand the ecological and evolutionary dynamics of antagonistic interactions, such as the potential for coevolution, but also for the successful management of pest populations through biological control.
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Affiliation(s)
- Adam J Martinez
- Department of Entomology, University of Georgia, Athens GA 30602, USA
| | - Shannon G Ritter
- Department of Entomology, University of Georgia, Athens GA 30602, USA
| | - Matthew R Doremus
- Department of Entomology, University of Georgia, Athens GA 30602, USA
| | - Jacob A Russell
- Department of Biology, Drexel University, Philadelphia PA 19104, USA
| | - Kerry M Oliver
- Department of Entomology, University of Georgia, Athens GA 30602, USA
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