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Northrup GR, White A, Parratt SR, Rozins C, Laine AL, Boots M. The evolutionary dynamics of hyperparasites. J Theor Biol 2024; 582:111741. [PMID: 38280543 DOI: 10.1016/j.jtbi.2024.111741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 12/14/2023] [Accepted: 01/16/2024] [Indexed: 01/29/2024]
Abstract
Evolutionary theory has typically focused on pairwise interactions, such as those between hosts and parasites, with relatively little work having been carried out on more complex interactions including hyperparasites: parasites of parasites. Hyperparasites are common in nature, with the chestnut blight fungus virus CHV-1 a well-known natural example, but also notably include the phages of important human bacterial diseases. We build a general modeling framework for the evolution of hyperparasites that highlights the central role that the ability of a hyperparasite to be transmitted with its parasite plays in their evolution. A key result is that hyperparasites which transmit with their parasite hosts (hitchhike) will be selected for lower virulence, trending towards hypermutualism or hypercommensalism. We examine the impact on the evolution of hyperparasite systems of a wide range of host and parasite traits showing, for example, that high parasite virulence selects for higher hyperparasite virulence resulting in reductions in parasite virulence when hyperparasitized. Furthermore, we show that acute parasite infection will also select for increased hyperparasite virulence. Our results have implications for hyperparasite research, both as biocontrol agents and for their role in shaping community ecology and evolution and moreover emphasize the importance of understanding evolution in the context of multitrophic interactions.
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Affiliation(s)
- Graham R Northrup
- Center for Computational Biology, College of Engineering, University of California, Berkeley, CA, USA.
| | - Andy White
- Maxwell Institute for Mathematical Sciences, Heriot-Watt University, Edinburgh, UK; Department of Mathematics, Heriot-Watt University, Edinburgh, UK
| | - Steven R Parratt
- Department of Ecology, Evolution and Behaviour, University of Liverpool, Liverpool, UK
| | - Carly Rozins
- Department of Science and Technology Studies, Division of Natural Science, York University, Toronto, Ontario, Canada
| | - Anna-Liisa Laine
- Research Centre for Ecological Change, Organismal and Evolutionary Biology Research Programme, University of Helsinki, Finland; Department of Evolutionary Biology and Environmental Studies, University of Zurich, Switzerland
| | - Mike Boots
- Department of Integrative Biology, University of California Berkeley, CA, USA; Center for Ecology and Conservation, College of Life and Environmental Sciences, University of Exeter, Penryn Campus, UK
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Klein M, Stewart JD, Porter SS, Weedon JT, Kiers ET. Evolution of manipulative microbial behaviors in the rhizosphere. Evol Appl 2022; 15:1521-1536. [DOI: 10.1111/eva.13333] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 11/30/2021] [Accepted: 12/02/2021] [Indexed: 01/01/2023] Open
Affiliation(s)
- Malin Klein
- Department of Ecological Science Vrije Universiteit Amsterdam Amsterdam The Netherlands
| | - Justin D. Stewart
- Department of Ecological Science Vrije Universiteit Amsterdam Amsterdam The Netherlands
| | - Stephanie S. Porter
- School of Biological Sciences Washington State University Vancouver Washington USA
| | - James T. Weedon
- Department of Ecological Science Vrije Universiteit Amsterdam Amsterdam The Netherlands
| | - E. Toby Kiers
- Department of Ecological Science Vrije Universiteit Amsterdam Amsterdam The Netherlands
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Maurice S, Arnault G, Nordén J, Botnen SS, Miettinen O, Kauserud H. Fungal sporocarps house diverse and host-specific communities of fungicolous fungi. THE ISME JOURNAL 2021; 15:1445-1457. [PMID: 33432137 PMCID: PMC8115690 DOI: 10.1038/s41396-020-00862-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 11/23/2020] [Accepted: 11/30/2020] [Indexed: 11/16/2022]
Abstract
Sporocarps (fruit bodies) are the sexual reproductive stage in the life cycle of many fungi. They are highly nutritious and consequently vulnerable to grazing by birds and small mammals, and invertebrates, and can be infected by microbial and fungal parasites and pathogens. The complexity of communities thriving inside sporocarps is largely unknown. In this study, we revealed the diversity, taxonomic composition and host preference of fungicolous fungi (i.e., fungi that feed on other fungi) in sporocarps. We carried out DNA metabarcoding of the ITS2 region from 176 sporocarps of 11 wood-decay fungal host species, all collected within a forest in northeast Finland. We assessed the influence of sporocarp traits, such as lifespan, morphology and size, on the fungicolous fungal community. The level of colonisation by fungicolous fungi, measured as the proportion of non-host ITS2 reads, varied between 2.8-39.8% across the 11 host species and was largely dominated by Ascomycota. Host species was the major determinant of the community composition and diversity of fungicolous fungi, suggesting that host adaptation is important for many fungicolous fungi. Furthermore, the alpha diversity was consistently higher in short-lived and resupinate sporocarps compared to long-lived and pileate ones, perhaps due to a more hostile environment for fungal growth in the latter too. The fungicolous fungi represented numerous lineages in the fungal tree of life, among which a significant portion was poorly represented with reference sequences in databases.
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Affiliation(s)
- Sundy Maurice
- Section for Genetics and Evolutionary Biology, University of Oslo, Blindernveien 31, 0316, Oslo, Norway.
| | - Gontran Arnault
- Section for Genetics and Evolutionary Biology, University of Oslo, Blindernveien 31, 0316, Oslo, Norway
| | - Jenni Nordén
- Norwegian Institute for Nature Research, Gaustadalléen 21, 0349, Oslo, Norway
| | - Synnøve Smebye Botnen
- Section for Genetics and Evolutionary Biology, University of Oslo, Blindernveien 31, 0316, Oslo, Norway
| | - Otto Miettinen
- Finnish Museum of Natural History, University of Helsinki, P.O. Box 7, FI-00014, Helsinki, Finland
| | - Håvard Kauserud
- Section for Genetics and Evolutionary Biology, University of Oslo, Blindernveien 31, 0316, Oslo, Norway
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Mohan S, Kiran Kumar K, Sutar V, Saha S, Rowe J, Davies KG. Plant Root-Exudates Recruit Hyperparasitic Bacteria of Phytonematodes by Altered Cuticle Aging: Implications for Biological Control Strategies. FRONTIERS IN PLANT SCIENCE 2020; 11:763. [PMID: 32582268 PMCID: PMC7296116 DOI: 10.3389/fpls.2020.00763] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Accepted: 05/13/2020] [Indexed: 05/21/2023]
Abstract
Phytonematodes are globally important functional components of the belowground ecology in both natural and agricultural soils; they are a diverse group of which some species are economically important pests, and environmentally benign control strategies are being sought to control them. Using eco-evolutionary theory, we test the hypothesis that root-exudates of host plants will increase the ability of a hyperparasitic bacteria, Pasteuria penetrans and other closely related bacteria, to infect their homologous pest nematodes, whereas non-host root exudates will not. Plant root-exudates from good hosts, poor hosts and non-hosts were characterized by gas chromatography-mass spectrometry (GC/MS) and we explore their interaction on the attachment of the hyperparasitic bacterial endospores to homologous and heterologous pest nematode cuticles. Although GC/MS did not identify any individual compounds as responsible for changes in cuticle susceptibility to endospore adhesion, standardized spore binding assays showed that Pasteuria endospore adhesion decreased with nematode age, and that infective juveniles pre-treated with homologous host root-exudates reduced the aging process and increased attachment of endospores to the nematode cuticle, whereas non-host root-exudates did not. We develop a working model in which plant root exudates manipulate the nematode cuticle aging process, and thereby, through increased bacterial endospore attachment, increase bacterial infection of pest nematodes. This we suggest would lead to a reduction of plant-parasitic nematode burden on the roots and increases plant fitness. Therefore, by the judicious manipulation of environmental factors produced by the plant root and by careful crop rotation this knowledge can help in the development of environmentally benign control strategies.
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Affiliation(s)
- Sharad Mohan
- Division of Nematology, Indian Council of Agricultural Research, Indian Agricultural Research Institute, New Delhi, India
- *Correspondence: Sharad Mohan,
| | - K. Kiran Kumar
- Indian Council of Agricultural Research, Central Citrus Research Institute, Nagpur, India
| | - Vivek Sutar
- Division of Nematology, Indian Council of Agricultural Research, Indian Agricultural Research Institute, New Delhi, India
| | - Supradip Saha
- Division of Agricultural Chemicals, Indian Council of Agricultural Research, Indian Agricultural Research Institute, New Delhi, India
| | - Janet Rowe
- Plant Pathology and Microbiology, Rothamsted Research, Harpenden, United Kingdom
| | - Keith G. Davies
- Department of Biological and Environmental Sciences, University of Hertfordshire, Hatfield, United Kingdom
- Norwegian Institute of Bioeconomy Research, Ås, Norway
- Keith G. Davies,
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Raffa KF, Bonello P, Orrock JL. Why do entomologists and plant pathologists approach trophic relationships so differently? Identifying biological distinctions to foster synthesis. THE NEW PHYTOLOGIST 2020; 225:609-620. [PMID: 31494947 DOI: 10.1111/nph.16181] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Accepted: 08/29/2019] [Indexed: 06/10/2023]
Abstract
Plant interactions with herbivores and pathogens are among the most widespread ecological relationships, and show many congruent properties. Despite these similarities, general models describing how plant defenses function in ecosystems, and the prioritization of responses to emerging challenges such as climate change, invasive species and habitat alteration, often differ markedly between entomologists and plant pathologists. We posit that some fundamental distinctions between how insects and pathogens interact with plants underlie these differences. We propose a conceptual framework to help incorporate these distinctions into robust models and research priorities. The most salient distinctions include features of host-searching behavior, evasion of plant defenses, plant tolerance to utilization, and sources of insect and microbial population regulation. Collectively, these features lead to relatively more diffuse and environmentally mediated plant-insect interactions, and more intimate and genetically driven plant-pathogen interactions. Specific features of insect vs pathogen life histories can also yield different patterns of spatiotemporal dynamics. These differences can become increasingly pronounced when scaling from controlled laboratory to open ecological systems. Integrating these differences alongside similarities can foster improved models and research approaches to plant defense, trophic interactions, coevolutionary dynamics, food security and resource management, and provide guidance as traditional departments increase collaborations, or merge into larger units.
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Affiliation(s)
- Kenneth F Raffa
- Department of Entomology, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Pierluigi Bonello
- Department of Plant Pathology, The Ohio State University, Columbus, OH, 43210, USA
| | - John L Orrock
- Department of Integrative Biology, University of Wisconsin-Madison, Madison, WI, 53706, USA
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Németh MZ, Pintye A, Horváth ÁN, Vági P, Kovács GM, Gorfer M, Kiss L. Green Fluorescent Protein Transformation Sheds More Light on a Widespread Mycoparasitic Interaction. PHYTOPATHOLOGY 2019; 109:1404-1416. [PMID: 30900938 DOI: 10.1094/phyto-01-19-0013-r] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Powdery mildews, ubiquitous obligate biotrophic plant pathogens, are often attacked in the field by mycoparasitic fungi belonging to the genus Ampelomyces. Some Ampelomyces strains are commercialized biocontrol agents of crop pathogenic powdery mildews. Using Agrobacterium tumefaciens-mediated transformation (ATMT), we produced stable Ampelomyces transformants that constitutively expressed green fluorescent protein (GFP) to (i) improve the visualization of the mildew-Ampelomyces interaction and (ii) decipher the environmental fate of Ampelomyces fungi before and after acting as a mycoparasite. Detection of Ampelomyces structures, and especially hyphae, was greatly enhanced when diverse powdery mildew, leaf, and soil samples containing GFP transformants were examined with fluorescence microscopy compared with brightfield and differential interference contrast optics. We showed for the first time, to our knowledge, that Ampelomyces strains can persist up to 21 days on mildew-free host plant surfaces, where they can attack powdery mildew structures as soon as these appear after this period. As saprobes in decomposing, powdery mildew-infected leaves on the ground and also in autoclaved soil, Ampelomyces strains developed new hyphae but did not sporulate. These results indicate that Ampelomyces strains occupy a niche in the phyllosphere where they act primarily as mycoparasites of powdery mildews. Our work has established a framework for a molecular genetic toolbox for the genus Ampelomyces using ATMT.
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Affiliation(s)
- Márk Z Németh
- 1Plant Protection Institute, Centre for Agricultural Research, Hungarian Academy of Sciences, H-1525 Budapest, Hungary
| | - Alexandra Pintye
- 1Plant Protection Institute, Centre for Agricultural Research, Hungarian Academy of Sciences, H-1525 Budapest, Hungary
| | - Áron N Horváth
- 1Plant Protection Institute, Centre for Agricultural Research, Hungarian Academy of Sciences, H-1525 Budapest, Hungary
| | - Pál Vági
- 1Plant Protection Institute, Centre for Agricultural Research, Hungarian Academy of Sciences, H-1525 Budapest, Hungary
- 2Department of Plant Anatomy, Institute of Biology, Eötvös Loránd University, H-1117 Budapest, Hungary
| | - Gábor M Kovács
- 1Plant Protection Institute, Centre for Agricultural Research, Hungarian Academy of Sciences, H-1525 Budapest, Hungary
- 2Department of Plant Anatomy, Institute of Biology, Eötvös Loránd University, H-1117 Budapest, Hungary
| | - Markus Gorfer
- 3Austrian Institute of Technology, BOKU University of Natural Resources and Life Sciences, A-3430 Tulln, Austria
| | - Levente Kiss
- 1Plant Protection Institute, Centre for Agricultural Research, Hungarian Academy of Sciences, H-1525 Budapest, Hungary
- 4Institute for Life Sciences and the Environment, Centre for Crop Health, University of Southern Queensland, Toowoomba, Queensland 4350, Australia
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Numminen E, Vaumourin E, Parratt SR, Poulin L, Laine AL. Variation and correlations between sexual, asexual and natural enemy resistance life-history traits in a natural plant pathogen population. BMC Evol Biol 2019; 19:142. [PMID: 31299905 PMCID: PMC6624897 DOI: 10.1186/s12862-019-1468-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Accepted: 06/26/2019] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Understanding the mechanisms by which diversity is maintained in pathogen populations is critical for epidemiological predictions. Life-history trade-offs have been proposed as a hypothesis for explaining long-term maintenance of variation in pathogen populations, yet the empirical evidence supporting trade-offs has remained mixed. This is in part due to the challenges of documenting successive pathogen life-history stages in many pathosystems. Moreover, little is understood of the role of natural enemies of pathogens on their life-history evolution. RESULTS We characterize life-history-trait variation and possible trade-offs in fungal pathogen Podosphaera plantaginis infecting the host plant Plantago lanceolata. We measured the timing of both asexual and sexual stages, as well as resistance to a hyperparasite of seven pathogen strains that vary in their prevalence in nature. We find significant variation among the strains in their life-history traits that constitute the infection cycle, but no evidence for trade-offs among pathogen development stages, apart from fast pathogen growth coninciding with fast hyperparasite growth. Also, the seemingly least fit pathogen strain was the most prevalent in the nature. CONCLUSIONS We conclude that in the nature environmental variation, and interactions with the antagonists of pathogens themselves may maintain variation in pathogen populations.
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Affiliation(s)
- Elina Numminen
- Department of Biosciences, University of Helsinki, Viikinkaari 1, PO Box 65, FI-00014, Helsinki, Finland.
| | - Elise Vaumourin
- Department of Biosciences, University of Helsinki, Viikinkaari 1, PO Box 65, FI-00014, Helsinki, Finland
| | - Steven R Parratt
- Department of Biosciences, University of Helsinki, Viikinkaari 1, PO Box 65, FI-00014, Helsinki, Finland.,University of Liverpool, Institute of Integrative Biology, Liverpool, L69 3BX, UK
| | - Lucie Poulin
- Department of Biosciences, University of Helsinki, Viikinkaari 1, PO Box 65, FI-00014, Helsinki, Finland.,Université de Nantes, Faculté des Sciences et des Techniques, Laboratoire de Biologie et de Pathologie Végétales (LBPV), EA 1157, SFR 4207 QUASAV, 2, rue de la Houssinière, BP 92 208, F-44322, Nantes Cedex 3, France
| | - Anna-Liisa Laine
- Department of Biosciences, University of Helsinki, Viikinkaari 1, PO Box 65, FI-00014, Helsinki, Finland.,Department of Evolutionary Biology and Environmental Studies, University of Zurich, Winterthurerstrasse 190, CH-8057, Zurich, Switzerland
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Affiliation(s)
- Nathan Vannier
- Max Planck Institute for Plant Breeding Research, Cologne, Germany
| | - Matthew Agler
- Institute of Microbiology, Friedrich Schiller University, Jena, Germany
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10
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Panstruga R, Kuhn H. Mutual interplay between phytopathogenic powdery mildew fungi and other microorganisms. MOLECULAR PLANT PATHOLOGY 2019; 20:463-470. [PMID: 30467940 PMCID: PMC6637862 DOI: 10.1111/mpp.12771] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Powdery mildew is a common and widespread plant disease of considerable agronomic relevance. It is caused by obligate biotrophic fungal pathogens which, in most cases, epiphytically colonize aboveground plant tissues. The disease has been typically studied as a binary interaction of the fungal pathogen with its plant hosts, neglecting, for the most part, the mutual interplay with the wealth of other microorganisms residing in the phyllo- and/or rhizosphere and roots. However, the establishment of powdery mildew disease can be impacted by the presence/absence of host-associated microbiota (epi- and endophytes) and, conversely, plant colonization by powdery mildew fungi might disturb indigenous microbial community structures. In addition, other (foliar) phytopathogens could interact with powdery mildews, and mycoparasites may affect the outcome of plant-powdery mildew interactions. In this review, we discuss the current knowledge regarding the intricate and multifaceted interplay of powdery mildew fungi, host plants and other microorganisms, and outline current gaps in our knowledge, thereby setting the basis for potential future research directions.
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Affiliation(s)
- Ralph Panstruga
- Unit of Plant Molecular Cell Biology, Institute for Biology IRWTH Aachen UniversityWorringerweg 1Aachen52056Germany
| | - Hannah Kuhn
- Unit of Plant Molecular Cell Biology, Institute for Biology IRWTH Aachen UniversityWorringerweg 1Aachen52056Germany
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Pascale A, Proietti S, Pantelides IS, Stringlis IA. Modulation of the Root Microbiome by Plant Molecules: The Basis for Targeted Disease Suppression and Plant Growth Promotion. FRONTIERS IN PLANT SCIENCE 2019; 10:1741. [PMID: 32038698 PMCID: PMC6992662 DOI: 10.3389/fpls.2019.01741] [Citation(s) in RCA: 212] [Impact Index Per Article: 42.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Accepted: 12/11/2019] [Indexed: 05/18/2023]
Abstract
Plants host a mesmerizing diversity of microbes inside and around their roots, known as the microbiome. The microbiome is composed mostly of fungi, bacteria, oomycetes, and archaea that can be either pathogenic or beneficial for plant health and fitness. To grow healthy, plants need to surveil soil niches around the roots for the detection of pathogenic microbes, and in parallel maximize the services of beneficial microbes in nutrients uptake and growth promotion. Plants employ a palette of mechanisms to modulate their microbiome including structural modifications, the exudation of secondary metabolites and the coordinated action of different defence responses. Here, we review the current understanding on the composition and activity of the root microbiome and how different plant molecules can shape the structure of the root-associated microbial communities. Examples are given on interactions that occur in the rhizosphere between plants and soilborne fungi. We also present some well-established examples of microbiome harnessing to highlight how plants can maximize their fitness by selecting their microbiome. Understanding how plants manipulate their microbiome can aid in the design of next-generation microbial inoculants for targeted disease suppression and enhanced plant growth.
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Affiliation(s)
- Alberto Pascale
- Department of Agricultural Sciences, University of Naples Federico II, Naples, Italy
| | - Silvia Proietti
- Department of Ecological and Biological Sciences, University of Tuscia, Viterbo, Italy
| | - Iakovos S. Pantelides
- Department of Agricultural Sciences, Biotechnology and Food Science, Cyprus University of Technology, Limassol, Cyprus
- *Correspondence: Iakovos S. Pantelides, ; Ioannis A. Stringlis,
| | - Ioannis A. Stringlis
- Plant-Microbe Interactions, Department of Biology, Science4Life, Utrecht University, Utrecht, Netherlands
- *Correspondence: Iakovos S. Pantelides, ; Ioannis A. Stringlis,
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Parratt SR, Laine A. Pathogen dynamics under both bottom-up host resistance and top-down hyperparasite attack. J Appl Ecol 2018; 55:2976-2985. [PMID: 30449900 PMCID: PMC6220889 DOI: 10.1111/1365-2664.13185] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2018] [Accepted: 04/19/2018] [Indexed: 02/04/2023]
Abstract
The relative importance of bottom-up versus top-down control of population dynamics has been the focus of much debate. In infectious disease biology, research is typically focused on the bottom-up process of host resistance, wherein the direction of control flows from the lower to the higher trophic level to impact on pathogen population size and epidemiology. However, the importance of top-down control by a pathogen's natural enemies has been mostly overlooked.Here, we explore the effects of, and interaction between, host genotype (i.e., genetic susceptibility to pathogen infection) and infection by a hyperparasitic fungus, Ampelomyces spp., on the establishment and early epidemic growth and transmission of a powdery mildew plant pathogen (Podosphaera plantaginis). We used a semi-natural field experiment to contrast the impacts of hyperparasite infection, host-plant resistance and spatial structure to reveal the key factors that determine pathogen spread. We then used a laboratory-based inoculation approach to test whether the field experiment results hold across multiple pathogen-host genetic combinations and to explore hyperparasite effects on the pathogen's later life-history stages.We found that hyperparasite infection had a negligible effect on within-host infection development and between-host spread of the pathogen during the onset of epidemics. In contrast, host-plant resistance was the major determinant of whether plants became infected, and host genotype and proximity to an infection source determined infection severity.Our laboratory study showed that, while the interaction between host and pathogen genotypes was the key determinant of infection outcome, hyperparasitism did, on average, reduce the severity of infection. Moreover, hyperparasite infection negatively influenced the production of the pathogen's overwintering structures. Synthesis and applications. Our results suggest that bottom-up host resistance affects pathogen spread, but top-down control of powdery mildew pathogens is likely more effective against later life-history stages. Further, while hyperparasitism in this system can reduce early pathogen growth under stable laboratory conditions, this effect is not detectable in a semi-natural environment. Considering the effects of hyperparasites at multiple points in pathogen's life history will be important when considering hyperparasite-derived biocontrol measures in other natural and agricultural systems.
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Affiliation(s)
- Steven R. Parratt
- Research Centre for Ecological ChangeUniversity of HelsinkiHelsinkiFinland
| | - Anna‐Liisa Laine
- Research Centre for Ecological ChangeUniversity of HelsinkiHelsinkiFinland
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