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Krone MJ, Dong Y, Mideros SX. Effect of Quantitative Wheat Resistance on the Aggressiveness of Fusarium graminearum. PHYTOPATHOLOGY 2024; 114:1577-1586. [PMID: 38669176 DOI: 10.1094/phyto-06-23-0206-r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/28/2024]
Abstract
Little is known about the selection pressures acting on plant pathogen populations, especially those applied by quantitative forms of resistance. Fusarium graminearum causes Fusarium head blight in wheat, producing significant yield losses and mycotoxin contamination. Quantitative host resistance is the best method to control Fusarium head blight. However, there needs to be more understanding of how disease resistance affects the evolution of plant pathogens. The aim of this study was to determine if the presence or absence of wheat resistance influenced the fitness components and genomic regions of F. graminearum. Thirty-one isolates from highly susceptible and 25 isolates from moderately resistant wheat lines were used. Isolate aggressiveness was measured by the area under the disease progress curve, visually damaged kernels, and deoxynivalenol contamination. The in vitro growth rate and spore production were also measured. Two whole-genome scans for selection were conducted with 333,297 single-nucleotide polymorphisms. One scan looked for signatures of selection in the entire sample, and the other scan was for divergent selection between the isolates from moderately resistant wheat and highly susceptible wheat. The subsample of isolates from highly susceptible wheat was primarily aggressive. Several regions of the F. graminearum genome with signatures for selection were identified. The moderately resistant wheat varieties used in this study did not select more aggressive isolates, suggesting that quantitative resistance is a durable method to control Fusarium head blight.
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Affiliation(s)
- Mara J Krone
- Department of Crop Sciences, University of Illinois, Urbana-Champaign, IL 61801
| | - Yanhong Dong
- Department of Plant Pathology, University of Minnesota, St. Paul, MN 55108
| | - Santiago X Mideros
- Department of Crop Sciences, University of Illinois, Urbana-Champaign, IL 61801
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2
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Bithell SL, Asif MA, Backhouse D, Drenth A, Harden S, Hobson K. Selection for Phytophthora Root Rot Resistance in Chickpea Crosses Affects Yield Potential of Chickpea × Cicer echinospermum Backcross Derivatives. PLANTS (BASEL, SWITZERLAND) 2024; 13:1432. [PMID: 38891240 PMCID: PMC11174912 DOI: 10.3390/plants13111432] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2024] [Revised: 05/10/2024] [Accepted: 05/14/2024] [Indexed: 06/21/2024]
Abstract
Phytophthora root rot (PRR) of chickpea (Cicer arietinum) caused by Phytophthora medicaginis is an important disease. Partial resistance to PRR is sourced from Cicer echinospermum. In this study, we evaluated if lines with low levels of PRR foliage symptoms in two contrasting recombinant inbred line (RIL) populations parented by chickpea cultivars (Yorker and Rupali) and 04067-81-2-1-1 (C. echinospermum, interspecific breeding line) had a significant drag on yield parameters. For the Yorker × 04067-81-2-1-1 population with the highest level of PRR resistance, in the absence of PRR, low foliage symptom RIL had significantly later flowering and podding, lower grain yields, and lighter seed and shorter plant phenotypes than high foliage symptom RIL. A quantitative trait locus analysis identified significant QTL for flowering, height, 100-seed weight, and yield, and there was a significantly higher frequency of alleles for the negative agronomic traits (i.e., drag) from the 04067-81-2-1-1 parent in low foliage symptom RIL than in high foliage symptom RIL. For the Rupali × 04067-81-2-1-1 population with lower levels of PRR resistance, in the absence of PRR, low foliage symptom RIL had significantly lighter seed and shorter plants than high foliage symptom RIL. Significant QTL were detected, the majority were for the timing of flowering and podding (n = 18), others were for plant height, yield, and 100-seed weight. For this second population, the frequency of alleles for the negative agronomic traits from the 04067-81-2-1-1 parent did not differ between low and high foliage symptom RIL. The 100 seed weight of RIL under moderate PRR disease pressure showed some promise as a yield component trait to identify phenotypes with both high levels of PRR resistance and grain yield potential for further seed number evaluations. We identified that large population sizes are required to enable selection among chickpea × C. echinospermum crosses for high levels of PRR resistance without a significant drag on yield.
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Affiliation(s)
- Sean L. Bithell
- New South Wales Department of Primary Industries, Tamworth, NSW 2340, Australia
| | - Muhammd A. Asif
- Chickpea Breeding Australia, New South Wales Department of Primary Industries, Tamworth Agricultural Institute, Tamworth, NSW 2340, Australia; (M.A.A.)
| | - David Backhouse
- School of Environmental and Rural Sciences, University of New England, Armidale, NSW 2350, Australia;
| | - Andre Drenth
- Centre for Horticultural Science, University of Queensland, Brisbane, QLD 4072, Australia;
| | - Steve Harden
- New South Wales Department of Primary Industries, Tamworth, NSW 2340, Australia
| | - Kristy Hobson
- Chickpea Breeding Australia, New South Wales Department of Primary Industries, Tamworth Agricultural Institute, Tamworth, NSW 2340, Australia; (M.A.A.)
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3
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Cornelsen JE, Ort NW, Gabert RK, Epp I, Rempel CB. Current and potential pest threats for canola in the Canadian Prairies. PEST MANAGEMENT SCIENCE 2024; 80:2220-2234. [PMID: 37899491 DOI: 10.1002/ps.7858] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 10/07/2023] [Accepted: 10/26/2023] [Indexed: 10/31/2023]
Abstract
Canola/oilseed rape (Brassica napus L.) production in Canada has increased to become a foundational crop in the Canadian Prairies and an important economic driver of this region. The increase in seeded area, and by association its reduction in-crop rotation frequency, has made it easier for pests to overcome current recommended agronomic management practices. The Canola Council of Canada has been successful in involving the entire commodity value chain in promoting and strengthening the Canadian canola industry; however, because of this production increase it is critically important to understand, evaluate and mitigate the potential risks of canola yield losses to current and potential pests. This Perspective provides an overview of what are currently the most damaging insects, pathogens and weeds to canola in the Canadian Prairies, potential future threats and opportunities farmers, agronomists and researchers can take to minimize these risks. © 2023 Society of Chemical Industry.
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Affiliation(s)
| | - Nathaniel Ww Ort
- Canola Council of Canada, Winnipeg, Canada
- University of Saskatchewan, Saskatoon, Canada
| | | | - Ian Epp
- Canola Council of Canada, Winnipeg, Canada
| | - Curtis B Rempel
- Canola Council of Canada, Winnipeg, Canada
- University of Manitoba, Winnipeg, Canada
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Hossain MM, Sultana F, Yesmin L, Rubayet MT, Abdullah HM, Siddique SS, Bhuiyan MAB, Yamanaka N. Understanding Phakopsora pachyrhizi in soybean: comprehensive insights, threats, and interventions from the Asian perspective. Front Microbiol 2024; 14:1304205. [PMID: 38274768 PMCID: PMC10808435 DOI: 10.3389/fmicb.2023.1304205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Accepted: 12/05/2023] [Indexed: 01/27/2024] Open
Abstract
Soybean (Glycine max L.) is an important crop in Asia, accounting for 17% of global soybean cultivation. However, this crop faces formidable challenges from the devastating foliar disease, Asian Soybean Rust (ASR), caused by Phakopsora pachyrhizi, a biotrophic fungus with a broad host range, causing substantial yield losses (10-100%) in Asia. This comprehensive review consolidates knowledge on ASR, encompassing its impact, historical perspectives, genetic diversity, epidemic drivers, early detection, risk assessment, and sustainable management strategies of ASR in the region. ASR has expanded globally from Asia, reaching Africa and Americas, driven by wind-dispersed urediniospores. Genetic diversity studies reveal the complexity of P. pachyrhizi, with distinct populations exhibiting varying virulence patterns. Factors affecting ASR epidemics in Asia include host susceptibility, landscape connectivity, climate, and environmental conditions. Understanding the interplay of these factors is essential for early intervention and control of ASR in soybean fields. Effectively managing ASR can exploit the utilization of diverse intervention strategies, encompassing disease forecasting, automated early detection, disease resistance, fungicide application, and biological control. A pivotal aspect of successful, sustainable disease management lies in reducing the ASR pathogen virulence and preventing it from developing fungicide resistance, while the highpoint of effectiveness in disease control is attained through a synergistic approach, integrating various strategies. In summary, this comprehensive review provides insights into multifaceted approaches that contribute to the development of sustainable and economically impactful soybean production in the face of the persistent threat of ASR in Asia.
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Affiliation(s)
- Md. Motaher Hossain
- Department of Plant Pathology, Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur, Bangladesh
| | - Farjana Sultana
- College of Agricultural Sciences, International University of Business Agriculture and Technology, Dhaka, Bangladesh
| | - Laboni Yesmin
- Department of Plant Pathology, Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur, Bangladesh
| | - Md. Tanbir Rubayet
- Department of Plant Pathology, Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur, Bangladesh
| | - Hasan M. Abdullah
- Department of Agroforestry and Environment, Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur, Bangladesh
| | - Shaikh Sharmin Siddique
- Department of Plant Pathology, Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur, Bangladesh
| | - Md. Abdullahil Baki Bhuiyan
- Department of Plant Pathology, Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur, Bangladesh
| | - Naoki Yamanaka
- Japan International Research Center for Agricultural Sciences (JIRCAS), Tsukuba, Ibaraki, Japan
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Leclerc M, Jumel S, Hamelin FM, Treilhaud R, Parisey N, Mammeri Y. Imaging with spatio-temporal modelling to characterize the dynamics of plant-pathogen lesions. PLoS Comput Biol 2023; 19:e1011627. [PMID: 37983276 PMCID: PMC10695395 DOI: 10.1371/journal.pcbi.1011627] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 12/04/2023] [Accepted: 10/23/2023] [Indexed: 11/22/2023] Open
Abstract
Within-host spread of pathogens is an important process for the study of plant-pathogen interactions. However, the development of plant-pathogen lesions remains practically difficult to characterize beyond the common traits such as lesion area. Here, we address this question by combining image-based phenotyping with mathematical modelling. We consider the spread of Peyronellaea pinodes on pea stipules that were monitored daily with visible imaging. We assume that pathogen propagation on host-tissues can be described by the Fisher-KPP model where lesion spread depends on both a logistic growth and an homogeneous diffusion. Model parameters are estimated using a variational data assimilation approach on sets of registered images. This modelling framework is used to compare the spread of an aggressive isolate on two pea cultivars with contrasted levels of partial resistance. We show that the expected slower spread on the most resistant cultivar is actually due to a significantly lower diffusion coefficient. This study shows that combining imaging with spatial mechanistic models can offer a mean to disentangle some processes involved in host-pathogen interactions and further development may allow a better identification of quantitative traits thereafter used in genetics and ecological studies.
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Affiliation(s)
- Melen Leclerc
- IGEPP, INRAE, Institut Agro, University of Rennes, Rennes, France
| | - Stéphane Jumel
- IGEPP, INRAE, Institut Agro, University of Rennes, Rennes, France
| | | | - Rémi Treilhaud
- IGEPP, INRAE, Institut Agro, University of Rennes, Rennes, France
| | - Nicolas Parisey
- IGEPP, INRAE, Institut Agro, University of Rennes, Rennes, France
| | - Youcef Mammeri
- ICJ, CNRS, Jean Monnet University, Saint-Etienne, France
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Levionnois S, Pradal C, Fournier C, Sanner J, Robert C. Modeling the Impact of Proportion, Sowing Date, and Architectural Traits of a Companion Crop on Foliar Fungal Pathogens of Wheat in Crop Mixtures. PHYTOPATHOLOGY 2023; 113:1876-1889. [PMID: 37097642 DOI: 10.1094/phyto-06-22-0197-r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/19/2023]
Abstract
Diversification of cropping systems is a lever for the management of epidemics. However, most research to date has focused on cultivar mixtures, especially for cereals, even though crop mixtures can also improve disease management. To investigate the benefits of crop mixtures, we studied the effect of different crop mixture characteristics (i.e., companion proportion, sowing date, and traits) on the protective effect of the mixture. We developed a SEIR (Susceptible, Exposed, Infectious, Removed) model of two damaging wheat diseases (Zymoseptoria tritici and Puccinia triticina), which were applied to different canopy components, ascribable to wheat and a theoretical companion crop. We used the model to study the sensitivity of disease intensity to the following parameters: wheat-versus-companion proportion, companion sowing date and growth, and architectural traits. For both pathogens, the companion proportion had the strongest effect, with 25% of companion reducing disease severity by 50%. However, changing companion growth and architectural traits also significantly improved the protective effect. The effect of companion characteristics was consistent across different weather conditions. After decomposing the dilution and barrier effects, the model suggested that the barrier effect is maximized for an intermediate proportion of companion crop. Our study thus supports crop mixtures as a promising strategy to improve disease management. Future studies should identify real species and determine the combination of host and companion traits to maximize the protective effect of the mixture. [Formula: see text] Copyright © 2023 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.
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Affiliation(s)
- Sébastien Levionnois
- UMR EcoSys, INRAE, AgroParisTech, Campus Agro Paris-Saclay, 91120 Palaiseau, France
- UMR AGAP Institut, Univ. Montpellier, CIRAD, INRAE, Institut Agro, 34398 Montpellier, France
| | - Christophe Pradal
- CIRAD, UMR AGAP Institut, 34398 Montpellier, France
- INRIA & LIRMM, Univ. Montpellier, CNRS, 34090 Montpellier, France
| | - Christian Fournier
- UMR LEPSE, Université de Montpellier, INRAE, Montpellier SupAgro, 34000 Montpellier, France
| | - Jonathan Sanner
- UMR EcoSys, INRAE, AgroParisTech, Campus Agro Paris-Saclay, 91120 Palaiseau, France
| | - Corinne Robert
- UMR EcoSys, INRAE, AgroParisTech, Campus Agro Paris-Saclay, 91120 Palaiseau, France
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Olszak-Przybyś H, Korbecka-Glinka G, Patkowska E. Identification and Pathogenicity of Fusarium Isolated from Soybean in Poland. Pathogens 2023; 12:1162. [PMID: 37764970 PMCID: PMC10537759 DOI: 10.3390/pathogens12091162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 09/08/2023] [Accepted: 09/11/2023] [Indexed: 09/29/2023] Open
Abstract
Fungi belonging to the Fusarium genus are commonly isolated from soybean plants and seeds but not all of them are pathogenic. The aim of this study was to compare the pathogenicity among different Fusarium isolates obtained from soybean plants with disease symptoms originating from an experimental field located in the southeast of Poland. Nineteen fungal isolates were selected for the pathogenicity assay, including eight isolates of F. oxysporum, six isolates of F. graminearum, four isolates of F. culmorum and one isolate of F. redolens. Species identification of these isolates was carried out using microscopic methods and sequencing of two genes: translation elongation factor 1-alpha (TEF1) and RNA polymerase second largest subunit (RPB2). To our knowledge, this is the first report of F. redolens being isolated from soybean in Europe. The pathogenicity test was set up by fungal inoculation of healthy soybean seeds of three cultivars: Abelina, Atlanta and Mavka. Symptoms were assessed seven days after inoculation. Disease area percentage of Fusarium inoculated seeds was significantly higher compared to uninoculated control. Nineteen isolates differed in their aggressiveness as the median disease area percentage ranged between 5.0 and 88.0% depending on isolate. The obtained isolates of four Fusarium species may be used in the future screening of soybean cultivars for resistance to these pathogens.
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Affiliation(s)
- Hanna Olszak-Przybyś
- Department of Plant Breeding and Biotechnology, Institute of Soil Science and Plant Cultivation-State Research, ul. Czartoryskich 8, 24-100 Puławy, Poland;
| | - Grażyna Korbecka-Glinka
- Department of Plant Breeding and Biotechnology, Institute of Soil Science and Plant Cultivation-State Research, ul. Czartoryskich 8, 24-100 Puławy, Poland;
| | - Elżbieta Patkowska
- Department of Plant Protection, Faculty of Horticulture and Landscape Architecture, University of Life Sciences in Lublin, ul. Leszczyńskiego 7, 20-069 Lublin, Poland
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Langlands-Perry C, Pitarch A, Lapalu N, Cuenin M, Bergez C, Noly A, Amezrou R, Gélisse S, Barrachina C, Parrinello H, Suffert F, Valade R, Marcel TC. Quantitative and qualitative plant-pathogen interactions call upon similar pathogenicity genes with a spectrum of effects. FRONTIERS IN PLANT SCIENCE 2023; 14:1128546. [PMID: 37235026 PMCID: PMC10206311 DOI: 10.3389/fpls.2023.1128546] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Accepted: 04/19/2023] [Indexed: 05/28/2023]
Abstract
Septoria leaf blotch is a foliar wheat disease controlled by a combination of plant genetic resistances and fungicides use. R-gene-based qualitative resistance durability is limited due to gene-for-gene interactions with fungal avirulence (Avr) genes. Quantitative resistance is considered more durable but the mechanisms involved are not well documented. We hypothesize that genes involved in quantitative and qualitative plant-pathogen interactions are similar. A bi-parental population of Zymoseptoria tritici was inoculated on wheat cultivar 'Renan' and a linkage analysis performed to map QTL. Three pathogenicity QTL, Qzt-I05-1, Qzt-I05-6 and Qzt-I07-13, were mapped on chromosomes 1, 6 and 13 in Z. tritici, and a candidate pathogenicity gene on chromosome 6 was selected based on its effector-like characteristics. The candidate gene was cloned by Agrobacterium tumefaciens-mediated transformation, and a pathology test assessed the effect of the mutant strains on 'Renan'. This gene was demonstrated to be involved in quantitative pathogenicity. By cloning a newly annotated quantitative-effect gene in Z. tritici that is effector-like, we demonstrated that genes underlying pathogenicity QTL can be similar to Avr genes. This opens up the previously probed possibility that 'gene-for-gene' underlies not only qualitative but also quantitative plant-pathogen interactions in this pathosystem.
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Affiliation(s)
- Camilla Langlands-Perry
- Université Paris-Saclay, INRAE, UR BIOGER, Palaiseau, France
- ARVALIS Institut du Végétal, Boigneville, France
| | - Anaïs Pitarch
- Université Paris-Saclay, INRAE, UR BIOGER, Palaiseau, France
| | - Nicolas Lapalu
- Université Paris-Saclay, INRAE, UR BIOGER, Palaiseau, France
| | - Murielle Cuenin
- Université Paris-Saclay, INRAE, UR BIOGER, Palaiseau, France
| | | | - Alicia Noly
- Université Paris-Saclay, INRAE, UR BIOGER, Palaiseau, France
| | - Reda Amezrou
- Université Paris-Saclay, INRAE, UR BIOGER, Palaiseau, France
| | | | - Célia Barrachina
- MGX-Montpellier GenomiX, Univ. Montpellier, CNRS, INSERM, Montpellier, France
| | - Hugues Parrinello
- MGX-Montpellier GenomiX, Univ. Montpellier, CNRS, INSERM, Montpellier, France
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Bithell SL, Drenth A, Backhouse D, Harden S, Hobson K. Inoculum production of Phytophthora medicaginis can be used to screen for partial resistance in chickpea genotypes. FRONTIERS IN PLANT SCIENCE 2023; 14:1115417. [PMID: 36890901 PMCID: PMC9986325 DOI: 10.3389/fpls.2023.1115417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/03/2022] [Accepted: 01/31/2023] [Indexed: 06/18/2023]
Abstract
Phytophthora root rot caused by Phytophthora medicaginis is an important disease of chickpeas (Cicer arietinum) in Australia with limited management options, increasing reliance on breeding for improved levels of genetic resistance. Resistance based on chickpea-Cicer echinospermum crosses is partial with a quantitative genetic basis provided by C. echinospermum and some disease tolerance traits originating from C. arietinum germplasm. Partial resistance is hypothesised to reduce pathogen proliferation, while tolerant germplasm may contribute some fitness traits, such as an ability to maintain yield despite pathogen proliferation. To test these hypotheses, we used P. medicaginis DNA concentrations in the soil as a parameter for pathogen proliferation and disease assessments on lines of two recombinant inbred populations of chickpea-C. echinospermum crosses to compare the reactions of selected recombinant inbred lines and parents. Our results showed reduced inoculum production in a C. echinospermum backcross parent relative to the C. arietinum variety Yorker. Recombinant inbred lines with consistently low levels of foliage symptoms had significantly lower levels of soil inoculum compared to lines with high levels of visible foliage symptoms. In a separate experiment, a set of superior recombinant inbred lines with consistently low levels of foliage symptoms was tested for soil inoculum reactions relative to control normalised yield loss. The in-crop P. medicaginis soil inoculum concentrations across genotypes were significantly and positively related to yield loss, indicating a partial resistance-tolerance spectrum. Disease incidence and the rankings for in-crop soil inoculum were correlated strongly to yield loss. These results indicate that soil inoculum reactions may be useful to identify genotypes with high levels of partial resistance.
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Affiliation(s)
- Sean L. Bithell
- Plant Systems, New South Wales Department of Primary Industries, Tamworth, NSW, Australia
| | - Andre Drenth
- Centre for Horticultural Science, University of Queensland, Brisbane, QLD, Australia
| | - David Backhouse
- School of Environmental and Rural Science, University of New England, Armidale, NSW, Australia
| | - Steve Harden
- Plant Systems, New South Wales Department of Primary Industries, Tamworth, NSW, Australia
| | - Kristy Hobson
- Plant Systems, New South Wales Department of Primary Industries, Tamworth, NSW, Australia
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Bradshaw MJ, Carey J, Liu M, Bartholomew HP, Jurick WM, Hambleton S, Hendricks D, Schnittler M, Scholler M. Genetic time traveling: sequencing old herbarium specimens, including the oldest herbarium specimen sequenced from kingdom Fungi, reveals the population structure of an agriculturally significant rust. THE NEW PHYTOLOGIST 2023; 237:1463-1473. [PMID: 36385249 DOI: 10.1111/nph.18622] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Accepted: 11/07/2022] [Indexed: 06/16/2023]
Abstract
Sequencing herbarium specimens can be instrumental in answering ecological, evolutionary, and taxonomic inquiries. We developed a protocol for sequencing herbarium specimens of rust fungi (Pucciniales) and proceeded to sequence specimens ranging from 4 to 211 yr old from five different genera. We then obtained sequences from an economically important biological control agent, Puccinia suaveolens, to highlight the potential of sequencing herbarium specimens in an ecological sense and to evaluate the following hypotheses: (1) The population structure of a plant pathogen changes over time, and (2) introduced pathogens are more diverse in their native range. Our efforts resulted in sequences from 87 herbarium specimens that revealed a high level of diversity with a population structure that exhibited spatial-temporal patterns. The specimens sequenced from Europe showed more diversity than the ones from North America, uncovering an invasion pattern likely related to its European native host in North America. Additionally, to the best of our knowledge, the specimen from France collected in c. 1811 is the oldest herbarium specimen sequenced from kingdom Fungi. In conclusion, sequencing old herbarium specimens is an important tool that can be extrapolated to better understand plant-microbe evolution and to evaluate old type specimens to solidify the taxonomy of plant pathogenic fungi.
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Affiliation(s)
- Michael J Bradshaw
- Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, 02138, USA
| | - Julie Carey
- Biodiversity and Bioresources, Agriculture and Agri-Food Canada, 960 Carling Avenue, Ottawa, ON, K1A 0C6, Canada
| | - Miao Liu
- Biodiversity and Bioresources, Agriculture and Agri-Food Canada, 960 Carling Avenue, Ottawa, ON, K1A 0C6, Canada
| | - Holly P Bartholomew
- Food Quality Laboratory, Agricultural Research Service, US Department of Agriculture, Beltsville, MD, 20705, USA
| | - Wayne M Jurick
- Food Quality Laboratory, Agricultural Research Service, US Department of Agriculture, Beltsville, MD, 20705, USA
| | - Sarah Hambleton
- Biodiversity and Bioresources, Agriculture and Agri-Food Canada, 960 Carling Avenue, Ottawa, ON, K1A 0C6, Canada
| | - Dylan Hendricks
- School of Environmental and Forest Sciences, University of Washington, Seattle, WA, 98195, USA
| | - Martin Schnittler
- General Botany and Plant Systematics, Institute of Botany and Landscape Ecology, Ernst Moritz Arndt University Greifswald, 17487, Greifswald, Germany
| | - Markus Scholler
- Staatliches Museum für Naturkunde, Abteilung Biowissenschaften, D-76133, Karlsruhe, Germany
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11
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Kong P, Daughtrey ML, Hong C. Differential Adaptation Has Resulted in Aggressiveness Variation of Calonectria pseudonaviculata on Hosts Buxus, Pachysandra, and Sarcococca. J Fungi (Basel) 2023; 9:jof9020181. [PMID: 36836296 PMCID: PMC9966688 DOI: 10.3390/jof9020181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Revised: 01/23/2023] [Accepted: 01/26/2023] [Indexed: 01/31/2023] Open
Abstract
Calonectria pseudonaviculata (Cps) infects Buxus (boxwood), Pachysandra (pachysandra), and Sarcococca spp. (sweet box); yet, how it adapts to its hosts has been unclear. Here, we performed serial passage experiments with the three hosts and measured Cps changes in three aggressiveness components: infectibility, lesion size, and conidial production. The detached leaves of individual hosts were inoculated with isolates (P0) from the originating host, followed by nine serial inoculations of new leaves of the same host with conidia from the infected leaves of the previous inoculation. All boxwood isolates maintained their capability of infection and lesion expansion through the 10 passages, whereas most non-boxwood isolates lost these abilities during the passages. Isolates from plants of origin (*-P0) and their descendants isolated from passages 5 (*-P5) and 10 (*-P10) were used to evaluate aggressiveness changes on all three hosts with cross-inoculation. While post-passage boxwood isolates gave enlarged lesions on pachysandra, sweet box P5 and pachysandra P10 isolates showed reduced aggressiveness on all hosts. Cps appears to be most adapted to boxwood and less adapted to sweet box and pachysandra. These results suggest speciation of Cps, with its coevolutionary pace with the hosts the fastest with boxwood, intermediate with sweet box, and the slowest with pachysandra.
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Affiliation(s)
- Ping Kong
- Hampton Roads Agricultural Research and Extension Center, Virginia Tech, Virginia Beach, VA 23455, USA
- Correspondence:
| | - Margery L. Daughtrey
- Long Island Horticultural Research and Extension Center, Cornell University, Riverhead, NY 11901, USA
| | - Chuanxue Hong
- Hampton Roads Agricultural Research and Extension Center, Virginia Tech, Virginia Beach, VA 23455, USA
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Emir M, Ozketen AC, Andac Ozketen A, Çelik Oğuz A, Huang M, Karakaya A, Rampitsch C, Gunel A. Increased levels of cell wall degrading enzymes and peptidases are associated with aggressiveness in a virulent isolate of Pyrenophora teres f. maculata. JOURNAL OF PLANT PHYSIOLOGY 2022; 279:153839. [PMID: 36370615 DOI: 10.1016/j.jplph.2022.153839] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2022] [Revised: 09/22/2022] [Accepted: 10/07/2022] [Indexed: 06/16/2023]
Abstract
Pyrenophora teres f. maculata (Ptm) is a fungal pathogen that causes the spot form of net blotch on barley and leads to economic losses in many of the world's barley-growing regions. Isolates of Ptm exhibit varying levels of aggressiveness that result in quantifiable changes in the severity of the disease. Previous research on plant-pathogen interactions has shown that such divergence is reflected in the proteome and secretome of the pathogen, with certain classes of proteins more prominent in aggressive isolates. Here we have made a detailed comparative analysis of the secretomes of two Ptm isolates, GPS79 and E35 (highly and mildly aggressive, respectively) using a proteomics-based approach. The secretomes were obtained in vitro using media amended with barley leaf sections. Secreted proteins therein were harvested, digested with trypsin, and fractionated offline by HPLC prior to LC-MS in a high-resolution instrument to obtain deep coverage of the proteome. The subsequent analysis used a label-free quantitative proteomics approach with relative quantification of proteins based on precursor ion intensities. A total of 1175 proteins were identified, 931 from Ptm and 244 from barley. Further analysis revealed 160 differentially abundant proteins with at least a two-fold abundance difference between the isolates, with the most enriched in the aggressive GPS79 secretome. These proteins were mainly cell-wall (carbohydrate) degrading enzymes and peptidases, with some oxidoreductases and other pathogenesis-related proteins also identified, suggesting that aggressiveness is associated with an improved ability of GPS79 to overcome cell wall barriers and neutralize host defense responses.
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Affiliation(s)
- Mahmut Emir
- Kirsehir-Ahi Evran University, Faculty of Arts and Sciences, Department of Chemistry, Kirsehir, Turkey
| | | | | | - Arzu Çelik Oğuz
- Ankara University Faculty of Agriculture, Department of Plant Protection, Dışkapı, Ankara, Turkey
| | - Mei Huang
- Agriculture and Agrifood Canada, Morden Research and Development Centre, Morden MB, Canada
| | - Aziz Karakaya
- Ankara University Faculty of Agriculture, Department of Plant Protection, Dışkapı, Ankara, Turkey
| | - Christof Rampitsch
- Agriculture and Agrifood Canada, Morden Research and Development Centre, Morden MB, Canada.
| | - Aslihan Gunel
- Kirsehir-Ahi Evran University, Faculty of Arts and Sciences, Department of Chemistry, Kirsehir, Turkey.
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13
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Vogel G, Giles G, Robbins KR, Gore MA, Smart CD. Quantitative Genetic Analysis of Interactions in the Pepper- Phytophthora capsici Pathosystem. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2022; 35:1018-1033. [PMID: 35914305 DOI: 10.1094/mpmi-12-21-0307-r] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
The development of pepper cultivars with durable resistance to the oomycete Phytophthora capsici has been challenging due to differential interactions between the species that allow certain pathogen isolates to cause disease on otherwise resistant host genotypes. Currently, little is known about the pathogen genes involved in these interactions. To investigate the genetic basis of P. capsici virulence on individual pepper genotypes, we inoculated sixteen pepper accessions, representing commercial varieties, sources of resistance, and host differentials, with 117 isolates of P. capsici, for a total of 1,864 host-pathogen combinations. Analysis of disease outcomes revealed a significant effect of inter-species genotype-by-genotype interactions, although these interactions were quantitative rather than qualitative in scale. Isolates were classified into five pathogen subpopulations, as determined by their genotypes at over 60,000 single-nucleotide polymorphisms (SNPs). While absolute virulence levels on certain pepper accessions significantly differed between subpopulations, a multivariate phenotype reflecting relative virulence levels on certain pepper genotypes compared with others showed the strongest association with pathogen subpopulation. A genome-wide association study (GWAS) identified four pathogen loci significantly associated with virulence, two of which colocalized with putative RXLR effector genes and another with a polygalacturonase gene cluster. All four loci appeared to represent broad-spectrum virulence genes, as significant SNPs demonstrated consistent effects regardless of the host genotype tested. Host genotype-specific virulence variants in P. capsici may be difficult to map via GWAS with all but excessively large sample sizes, perhaps controlled by genes of small effect or by multiple allelic variants that have arisen independently. [Formula: see text] Copyright © 2022 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.
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Affiliation(s)
- Gregory Vogel
- Plant Breeding and Genetics Section, School of Integrative Plant Science, Cornell University, Ithaca, NY 14853, U.S.A
- Plant Pathology and Plant-Microbe Biology Section, School of Integrative Plant Science, Cornell University, Geneva, NY 14456, U.S.A
| | - Garrett Giles
- Plant Pathology and Plant-Microbe Biology Section, School of Integrative Plant Science, Cornell University, Geneva, NY 14456, U.S.A
| | - Kelly R Robbins
- Plant Breeding and Genetics Section, School of Integrative Plant Science, Cornell University, Ithaca, NY 14853, U.S.A
| | - Michael A Gore
- Plant Breeding and Genetics Section, School of Integrative Plant Science, Cornell University, Ithaca, NY 14853, U.S.A
| | - Christine D Smart
- Plant Pathology and Plant-Microbe Biology Section, School of Integrative Plant Science, Cornell University, Geneva, NY 14456, U.S.A
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14
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Rapid and Accurate Detection of Gnomoniopsis smithogilvyi the Causal Agent of Chestnut Rot, through an Internally Controlled Multiplex PCR Assay. Pathogens 2022; 11:pathogens11080907. [PMID: 36015028 PMCID: PMC9415963 DOI: 10.3390/pathogens11080907] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Revised: 08/05/2022] [Accepted: 08/10/2022] [Indexed: 11/17/2022] Open
Abstract
The fungus Gnomoniopsis smithogilvyi is a significant threat to the production of sweet chestnut (Castanea sativa) nuts in Australia and worldwide. The pathogen causes nut rot, which leads to substantial production losses. Early and accurate diagnosis of the disease is essential to delineate and implement control strategies. A specific and sensitive multiplex PCR was developed based on the amplification of three barcode sequences of G. smithogilvyi. The assay reliability was enhanced by including the amplification of a host gene as an internal control. Primers were thoroughly evaluated in silico before assessing them in vitro. Primer annealing temperature and concentration were optimised to enhance the assay sensitivity and specificity. The assay detection limit ranged between 0.1 and 1.0 pg (5 and 50 fg/μL) of genomic DNA per reaction. No cross-reactivity was observed with genomic DNA from closely and distantly related fungal species. We also characterised Australian G. smithogilvyi isolates phenotypically and genotypically and found significant differences in morphologic and virulence traits of the isolates. An understanding of the virulence of G. smithogilvyi and the availability of a reliable and accurate diagnostic technique will enable earlier detection of the pathogen, which will contribute to effective control strategies for the disease.
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15
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Saubin M, Louet C, Bousset L, Fabre F, Frey P, Fudal I, Grognard F, Hamelin F, Mailleret L, Stoeckel S, Touzeau S, Petre B, Halkett F. Improving sustainable crop protection using population genetics concepts. Mol Ecol 2022; 32:2461-2471. [PMID: 35906846 DOI: 10.1111/mec.16634] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2021] [Revised: 06/23/2022] [Accepted: 06/24/2022] [Indexed: 10/16/2022]
Abstract
Growing genetically resistant plants allows pathogen populations to be controlled and reduces the use of pesticides. However, pathogens can quickly overcome such resistance. In this context, how can we achieve sustainable crop protection? This crucial question has remained largely unanswered despite decades of intense debate and research effort. In this study, we used a bibliographic analysis to show that the research field of resistance durability has evolved into three subfields: (i) 'plant breeding' (generating new genetic material), (ii) 'molecular interactions' (exploring the molecular dialogue governing plant-pathogen interactions) and (iii) 'epidemiology and evolution' (explaining and forecasting of pathogen population dynamics resulting from selection pressure(s) exerted by resistant plants). We argue that this triple split of the field impedes integrated research progress and ultimately compromises the sustainable management of genetic resistance. After identifying a gap among the three subfields, we argue that the theoretical framework of population genetics could bridge this gap. Indeed, population genetics formally explains the evolution of all heritable traits, and allows genetic changes to be tracked along with variation in population dynamics. This provides an integrated view of pathogen adaptation, in particular via evolutionary-epidemiological feedbacks. In this Opinion Note, we detail examples illustrating how such a framework can better inform best practices for developing and managing genetically resistant cultivars.
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Affiliation(s)
| | - Clémentine Louet
- Université de Lorraine, INRAE, IAM, Nancy, France.,Université Paris Saclay, INRAE, BIOGER, Thiverval-Grignon, France
| | - Lydia Bousset
- INRAE, Agrocampus Ouest, Université de Rennes, IGEPP, Le Rheu, France
| | - Frédéric Fabre
- INRAE, Bordeaux Sciences Agro, SAVE, F-33882 Villenave d'Ornon, France
| | - Pascal Frey
- Université de Lorraine, INRAE, IAM, Nancy, France
| | - Isabelle Fudal
- Université Paris Saclay, INRAE, BIOGER, Thiverval-Grignon, France
| | - Frédéric Grognard
- Université Côte d'Azur, Inria, INRAE, CNRS, Sorbonne Université, Biocore team, Sophia Antipolis, France
| | - Frédéric Hamelin
- INRAE, Agrocampus Ouest, Université de Rennes, IGEPP, Le Rheu, France
| | - Ludovic Mailleret
- Université Côte d'Azur, Inria, INRAE, CNRS, Sorbonne Université, Biocore team, Sophia Antipolis, France.,Université Côte d'Azur, INRAE, CNRS, ISA, Sophia Antipolis, France
| | - Solenn Stoeckel
- INRAE, Agrocampus Ouest, Université de Rennes, IGEPP, Le Rheu, France
| | - Suzanne Touzeau
- Université Côte d'Azur, Inria, INRAE, CNRS, Sorbonne Université, Biocore team, Sophia Antipolis, France
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Wu EJ, Wang YP, Yang LN, Zhao MZ, Zhan J. Elevating Air Temperature May Enhance Future Epidemic Risk of the Plant Pathogen Phytophthora infestans. J Fungi (Basel) 2022; 8:808. [PMID: 36012796 PMCID: PMC9410326 DOI: 10.3390/jof8080808] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Revised: 07/15/2022] [Accepted: 07/29/2022] [Indexed: 01/27/2023] Open
Abstract
Knowledge of pathogen adaptation to global warming is important for predicting future disease epidemics and food production in agricultural ecosystems; however, the patterns and mechanisms of such adaptation in many plant pathogens are poorly understood. Here, population genetics combined with physiological assays and common garden experiments were used to analyze the genetics, physiology, and thermal preference of pathogen aggressiveness in an evolutionary context using 140 Phytophthora infestans genotypes under five temperature regimes. Pathogens originating from warmer regions were more thermophilic and had a broader thermal niche than those from cooler regions. Phenotypic plasticity contributed ~10-fold more than heritability measured by genetic variance. Further, experimental temperatures altered the expression of genetic variation and the association of pathogen aggressiveness with the local temperature. Increasing experimental temperature enhanced the variation in aggressiveness. At low experimental temperatures, pathogens from warmer places produced less disease than those from cooler places; however, this pattern was reversed at higher experimental temperatures. These results suggest that geographic variation in the thermal preferences of pathogens should be included in modeling future disease epidemics in agricultural ecosystems in response to global warming, and greater attention should be paid to preventing the movement of pathogens from warmer to cooler places.
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Affiliation(s)
- E-Jiao Wu
- Institute of Pomology, Jiangsu Academy of Agricultural Sciences/Jiangsu Key Laboratory for Horticultural Crop Genetic Improvement, Nanjing 210014, China; (E.-J.W.); (M.-Z.Z.)
| | - Yan-Ping Wang
- College of Chemistry and Life Sciences, Chengdu Normal University, Chengdu 611130, China;
| | - Li-Na Yang
- Institute of Oceanography, Minjiang University, Fuzhou 350108, China;
| | - Mi-Zhen Zhao
- Institute of Pomology, Jiangsu Academy of Agricultural Sciences/Jiangsu Key Laboratory for Horticultural Crop Genetic Improvement, Nanjing 210014, China; (E.-J.W.); (M.-Z.Z.)
| | - Jiasui Zhan
- Department of Forest Mycology and Plant Pathology, Swedish University of Agricultural Science, 75007 Uppsala, Sweden
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17
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Gonçalves MP, Nogueira Júnior AF, Ribeiro RV, Amorim L. Monocyclic Components and Photosynthetic Damage Caused by Myrtle Rust in Guava Leaves. PHYTOPATHOLOGY 2022; 112:1467-1475. [PMID: 35050681 DOI: 10.1094/phyto-11-21-0480-r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Austropuccinia psidii, the causal agent of myrtle rust, was, for many years, restricted to the Americas, but since reaching Hawaii in 2005, the pathogen has expanded its global range exponentially. In Brazil, myrtle rust is the main fungal disease in guava plants. Despite this, there are few studies on guava rust epidemiology. The objectives of this study were to quantify the monocyclic components of rust and to evaluate the photosynthetic damage caused by A. psidii in young and old leaves of 'Paluma' guava. The monocyclic components of guava rust and gas exchange in healthy or inoculated (105 ml-1 urediniospores of A. psidii) leaves were quantified over time. Additionally, young leaves were inoculated with varying concentrations of A. psidii inoculum, and leaf gas exchange and chlorophyll fluorescence were measured at 25 days postinoculation. The relationship between the relative CO2 assimilation of a diseased leaf (Px) and a healthy leaf (Po) is related to disease severity (x) by Px/Po = (1 - x)β. The density of lesions, disease severity, and urediniospore production were high in young leaves, averaging 58 lesions cm-2, 50% leaf area diseased, and 2.5 × 104 urediniospores per lesion, respectively. Rust symptoms were not observed in old leaves, and resistance to infection did not cause any photosynthetic cost to these leaves. On young leaves, β was 2.13, indicating a reduction on CO2 assimilation at green tissues from symptomatic leaves. Our data revealed that photosynthesis reduction in diseased guava leaves was caused by biochemical and photochemical damage rather than by stomatal limitation.
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Affiliation(s)
- Manoel Penachio Gonçalves
- Department of Plant Pathology and Nematology, Luiz de Queiroz College of Agriculture, University of São Paulo, Piracicaba, SP 13418-900, Brazil
| | - Antonio Fernandes Nogueira Júnior
- Department of Plant Pathology and Nematology, Luiz de Queiroz College of Agriculture, University of São Paulo, Piracicaba, SP 13418-900, Brazil
| | - Rafael Vasconcelos Ribeiro
- Laboratory of Crop Physiology, Department of Plant Biology, Institute of Biology, University of Campinas, Campinas, SP 13083-970, Brazil
| | - Lilian Amorim
- Department of Plant Pathology and Nematology, Luiz de Queiroz College of Agriculture, University of São Paulo, Piracicaba, SP 13418-900, Brazil
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18
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Sakr N. Adaptation of Phytopathogenic Fungi to Quantitative Host Resistance: In Vitro Selection for Greater Aggressiveness in Fusarium Head Blight Species on Wheat. CYTOL GENET+ 2022. [DOI: 10.3103/s0095452722030112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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19
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Jin J, McCorkle KL, Cornish V, Carbone I, Lewis RS, Shew HD. Adaptation of Phytophthora nicotianae to Multiple Sources of Partial Resistance in Tobacco. PLANT DISEASE 2022; 106:906-917. [PMID: 34735283 DOI: 10.1094/pdis-06-21-1241-re] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Host resistance is an important tool in the management of black shank disease of tobacco. Race development leads to rapid loss of single-gene resistance, but the adaptation by Phytophthora nicotianae to sources of partial resistance from Beinhart 1000, Florida 301, and the Wz gene region introgressed from Nicotiana rustica is poorly characterized. In greenhouse environments, host genotypes with quantitative trait loci (QTLs) conferring resistance from multiple sources were initially inoculated with an aggressive isolate of race 0 or race 1 of P. nicotianae. The most aggressive isolate was selected after each of six host generations to inoculate the next generation of plants. The race 0 isolate demonstrated a continuous gradual increase in disease severity and percentage root rot on all sources of resistance except the genotype K 326 Wz/-, where a large increase in both was observed between generations 2 and 3. Adaptation by the race 0 isolate on Beinhart 1000 represents the first report of adaptation to this genotype by P. nicotianae. The race 1 isolate did not exhibit significant increases in aggressiveness over generations but exhibited a large increase in aggressiveness on K 326 Wz/- between generations 3 and 4. Molecular characterization of isolates recovered during selection was completed via double digest restriction-site associated DNA sequencing, but no polymorphisms were associated with the observed changes in aggressiveness. The rapid adaptation to Wz resistance and the gradual adaptation to other QTLs highlights the need to study the nature of Wz resistance and to conduct field studies on the efficacy of resistance gene rotation for disease management.
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Affiliation(s)
- Jing Jin
- Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, NC 27695
| | - Kestrel L McCorkle
- Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, NC 27695
| | - Vicki Cornish
- Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, NC 27695
| | - Ignazio Carbone
- Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, NC 27695
| | - Ramsey S Lewis
- Department of Crop and Soil Science, North Carolina State University, Raleigh, NC 27695
| | - H David Shew
- Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, NC 27695
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20
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Jin J, Shew HD. Impacts of Continued Exposure to a Susceptible Host Genotype on Aggressiveness of Phytophthora nicotianae Isolates Adapted to Multiple Sources of Partial Resistance. PLANT DISEASE 2022; 106:373-381. [PMID: 34282925 DOI: 10.1094/pdis-09-20-1972-re] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Pathogen adaptation can threaten the durability of partial resistance. Mixed plantings of susceptible and partially resistant varieties may prolong the effectiveness of partial resistance, but little is known about how continued exposure to a susceptible genotype can change the aggressiveness of pathogen isolates adapted to a source of partial resistance. The objective of this study was to examine the effects of continued exposure to a highly susceptible tobacco genotype on isolates of Phytophthora nicotianae that had been adapted to partial resistance. Isolates of P. nicotianae previously adapted to two sources of partial resistance were continually exposed to either the original host of adaptation or a susceptible host. After six generations of host exposure, isolates obtained from the partially resistant and the susceptible hosts were compared for their aggressiveness on the resistant host and for differences in expression of genes associated with pathogenicity and aggressiveness. Results suggested that exposure to the susceptible tobacco genotype reduced aggressiveness of isolates adapted to partial resistance in K 326 Wz/- but not of isolates adapted to partial resistance in Fla 301. Quantification of pathogenicity-associated gene expression using qRT-PCR suggested the rapid change in aggressiveness of isolates adapted to Wz-sourced partial resistance may have resulted from modification in gene expression in multiple genes.
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Affiliation(s)
- Jing Jin
- Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, NC 27695
| | - H David Shew
- Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, NC 27695
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21
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Boixel A, Chelle M, Suffert F. Patterns of thermal adaptation in a globally distributed plant pathogen: Local diversity and plasticity reveal two-tier dynamics. Ecol Evol 2022; 12:e8515. [PMID: 35127031 PMCID: PMC8796916 DOI: 10.1002/ece3.8515] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 12/08/2021] [Accepted: 12/16/2021] [Indexed: 11/11/2022] Open
Abstract
Plant pathogen populations inhabit patchy environments with contrasting, variable thermal conditions. We investigated the diversity of thermal responses in populations sampled over contrasting spatiotemporal scales, to improve our understanding of their dynamics of adaptation to local conditions. Samples of natural populations of the wheat pathogen Zymoseptoria tritici were collected from sites within the Euro-Mediterranean region subject to a broad range of climatic conditions. We tested for local adaptation, by accounting for the diversity of responses at the individual and population levels on the basis of key thermal performance curve parameters and "thermotype" (groups of individuals with similar thermal responses) composition. The characterization of phenotypic responses and genotypic structure revealed the following: (i) a high degree of individual plasticity and variation in sensitivity to temperature conditions across spatiotemporal scales and populations; and (ii) geographic variation in thermal response among populations, with major alterations due to seasonal patterns over the wheat-growing season. The seasonal shifts in functional composition suggest that populations are locally structured by selection, contributing to adaptation patterns. Further studies combining selection experiments and modeling are required to determine how functional group selection drives population dynamics and adaptive potential in response to thermal heterogeneity.
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Affiliation(s)
- Anne‐Lise Boixel
- Université Paris‐Saclay, INRAE, UR BIOGERThiverval‐GrignonFrance
| | - Michaël Chelle
- Université Paris‐Saclay, INRAE, AgroParisTech, UMR ECOSYSThiverval‐GrignonFrance
| | - Frédéric Suffert
- Université Paris‐Saclay, INRAE, UR BIOGERThiverval‐GrignonFrance
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22
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Baró A, Montesinos L, Badosa E, Montesinos E. Aggressiveness of Spanish Isolates of Xylella fastidiosa to Almond Plants of Different Cultivars Under Greenhouse Conditions. PHYTOPATHOLOGY 2021; 111:1994-2001. [PMID: 33749331 DOI: 10.1094/phyto-02-21-0049-r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
The aggressiveness of Spanish isolates of Xylella fastidiosa, representing different sequence types, were studied in almond plants of several cultivars by means of the dynamics of the population levels and symptoms, colonization and spread, and dose-effect relationships. Pathogen dynamics in almond plants under greenhouse conditions showed doubling times of 2.1 to 2.5 days during the exponential growth phase, with a maximum population size of about 35 days postinoculation (dpi). Differences in patterns in population dynamics were observed between sap and xylem tissue after the exponential growth, as population levels in the xylem tissue remained stable while viable cells in sap decreased. Population levels were higher in two upward zones than in the downward zone with respect to the inoculation area. The first symptoms were observed between 20 and 60 dpi, and disease severity increased over time at doubling times of 30 days, with a maximum observed at 120 dpi. Strains tested showed differences in population levels in the cultivars studied and were able to spread with different intensity from contaminated plant parts to new growing shoots after pruning. Two almond isolates showed different performance in dose-effect relationships when inoculated in cultivar Avijor. Whereas IVIA 5387.2 reached high population levels but showed high median effective dose (ED50) and minimal infective dose (MID) values, IVIA 5901.2 showed low population levels and low ED50 and MID values. This study has implications for the epidemiology of X. fastidiosa in almond crops, estimating doubling times of the pathogen in planta and of symptom development and showing differences in aggressiveness between strains.
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Affiliation(s)
- Aina Baró
- Institute of Food and Agricultural Technology-XaRTA-CIDSAV, University of Girona, 17003 Girona, Spain
| | - Laura Montesinos
- Institute of Food and Agricultural Technology-XaRTA-CIDSAV, University of Girona, 17003 Girona, Spain
| | - Esther Badosa
- Institute of Food and Agricultural Technology-XaRTA-CIDSAV, University of Girona, 17003 Girona, Spain
| | - Emilio Montesinos
- Institute of Food and Agricultural Technology-XaRTA-CIDSAV, University of Girona, 17003 Girona, Spain
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23
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Elvira-Recuenco M, Pando V, Berbegal M, Manzano Muñoz A, Iturritxa E, Raposo R. Influence of Temperature and Moisture Duration on Pathogenic Life History Traits of Predominant Haplotypes of Fusarium circinatum on Pinus spp. in Spain. PHYTOPATHOLOGY 2021; 111:2002-2009. [PMID: 33754808 DOI: 10.1094/phyto-10-20-0445-r] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Pathogen life history traits influence epidemic development and pathogen adaptive ability to interact with their hosts in different environments. Reduced traits variation may compromise pathogen evolutionary potential, which is particularly important for introduced pathogens. Fusarium circinatum (cause of pine pitch canker) is an invasive fungal pathogen in Europe, with current distribution restricted to forest stands of Pinus radiata and Pinus pinaster in northern Spain and Portugal. This study aimed to quantify pathogenic traits of Spanish isolates of F. circinatum, with two of the strains representing the two dominant haplotypes in the Spanish population. Disease severity was measured on P. radiata, analyzing the influence of temperature and moisture duration on infection as well as the influence of temperature on spore germination, sporulation, and mycelial growth. Results indicated that the isolate representing the most common haplotype caused more severe disease on P. radiata at 25 and 30°C compared with the second most common haplotype but caused less severe disease at 15°C. Spore germination was higher for the most common haplotype, which produced more spores at 20 and 25°C. The isolate showed hyphal melanization at 5°C, which has been associated with survival and may be important because no resting structures have been described for F. circinatum. Our study determined that longer moisture periods during infection result in more severe disease from 7 to 24 h, regardless of the isolate virulence. This is the first study on virulence of the most abundant haplotypes of F. circinatum in Spain as affected by temperatures and moisture.
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Affiliation(s)
| | - Valentín Pando
- ETS Ingenierías Agrarias, Universidad de Valladolid, 34004 Palencia, Spain
- Instituto de Gestion Forestal Sostenible (iuFOR), Universidad de Valladolid/INIA, Spain
| | - Mónica Berbegal
- Instituto Agroforestal Mediterráneo, Universitat Politècnica de València, 46022 Valencia, Spain
| | | | | | - Rosa Raposo
- INIA-CIFOR, 28040 Madrid, Spain
- Instituto de Gestion Forestal Sostenible (iuFOR), Universidad de Valladolid/INIA, Spain
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24
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Hudson O, Fulton JC, Dong AK, Dufault NS, Ali ME. Fusarium oxysporum f. sp. niveum Molecular Diagnostics Past, Present and Future. Int J Mol Sci 2021; 22:ijms22189735. [PMID: 34575897 PMCID: PMC8468614 DOI: 10.3390/ijms22189735] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 08/31/2021] [Accepted: 09/02/2021] [Indexed: 12/30/2022] Open
Abstract
Watermelon is an important commercial crop in the Southeastern United States and around the world. However, production is significantly limited by biotic factors including fusarium wilt caused by the hemibiotrophic fungus Fusarium oxysporum forma specialis niveum (Fon). Unfortunately, this disease has increased significantly in its presence over the last several decades as races have emerged which can overcome the available commercial resistance. Management strategies include rotation, improved crop resistance, and chemical control, but early and accurate diagnostics are required for appropriate management. Accurate diagnostics require molecular and genomic strategies due to the near identical genomic sequences of the various races. Bioassays exist for evaluating both the pathogenicity and virulence of an isolate but are limited by the time and resources required. Molecular strategies are still imperfect but greatly reduce the time to complete the diagnosis. This article presents the current state of the research surrounding races, both how races have been detected and diagnosed in the past and future prospects for improving the system of differentiation. Additionally, the available Fon genomes were analyzed using a strategy previously described in separate formae speciales avirulence gene association studies in Fusarium oxysporum races.
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Affiliation(s)
- Owen Hudson
- Department of Plant Pathology, University of Georgia, Tifton, GA 31793, USA; (O.H.); (A.K.D.)
| | - James C. Fulton
- Department of Plant Pathology, University of Florida, Gainesville, FL 32611, USA;
- Correspondence: (M.E.A.); (J.C.F.)
| | - Alexi K. Dong
- Department of Plant Pathology, University of Georgia, Tifton, GA 31793, USA; (O.H.); (A.K.D.)
| | - Nicholas S. Dufault
- Department of Plant Pathology, University of Florida, Gainesville, FL 32611, USA;
| | - Md Emran Ali
- Department of Plant Pathology, University of Georgia, Tifton, GA 31793, USA; (O.H.); (A.K.D.)
- Correspondence: (M.E.A.); (J.C.F.)
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Genome-wide association study for deoxynivalenol production and aggressiveness in wheat and rye head blight by resequencing 92 isolates of Fusarium culmorum. BMC Genomics 2021; 22:630. [PMID: 34461830 PMCID: PMC8404269 DOI: 10.1186/s12864-021-07931-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2020] [Accepted: 08/11/2021] [Indexed: 01/15/2023] Open
Abstract
Background Fusarium culmorum is an important pathogen causing head blight of cereals in Europe. This disease is of worldwide importance leading to reduced yield, grain quality, and contamination by mycotoxins. These mycotoxins are harmful for livestock and humans; therefore, many countries have strict regulatory limits for raw materials and processed food. Extensive genetic diversity is described among field populations of F. culmorum isolates for aggressiveness and production of the trichothecene mycotoxin deoxynivalenol (DON). However, the causes for this quantitative variation are not clear, yet. We analyzed 92 isolates sampled from different field populations in Germany, Russia, and Syria together with an international collection for aggressiveness and DON production in replicated field experiments at two locations in two years with two hosts, wheat and rye. The 30x coverage whole-genome resequencing of all isolates resulted in the identification of 130,389 high quality single nucleotide polymorphisms (SNPs) that were used for the first genome-wide association study in this phytopathogenic fungus. Results In wheat, 20 and 27 SNPs were detected for aggressiveness and DON content, respectively, of which 10 overlapped. Additionally, two different SNPs were significantly associated with aggressiveness in rye that were among those SNPs being associated with DON production in wheat. Most of the SNPs explained only a small proportion of genotypic variance (pG), however, four SNPs were associated with major quantitative trait loci (QTLs) with pG ranging from 12 to 48%. The QTL with the highest pG was involved in DON production and associated with a SNP most probably located within the Tri4 gene. Conclusions The diversity of 92 isolates of F. culmorum were captured using a heuristic approach. Key phenotypic traits, SNPs, and candidate genes underlying aggressiveness and DON production were identified. Clearly, many QTLs are responsible for aggressiveness and DON content in wheat, both traits following a quantitative inheritance. Several SNPs involved in DON metabolism, among them the Tri4 gene of the trichothecene pathway, were inferred as important source of variation in fungal aggressiveness. Using this information underlying the phenotypic variation will be of paramount importance in evaluating strategies for successful resistance breeding. Supplementary Information The online version contains supplementary material available at 10.1186/s12864-021-07931-5.
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Jin J, Shew HD. Components of Aggressiveness in Phytophthora nicotianae During Adaptation to Multiple Sources of Partial Resistance in Tobacco. PLANT DISEASE 2021; 105:1960-1966. [PMID: 33245258 DOI: 10.1094/pdis-09-20-1929-re] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Black shank is a devastating disease of tobacco caused by Phytophthora nicotianae. Host resistance has been an integral part of black shank management but after the loss of Php single-gene resistance following its widespread deployment in the 1990s, growers have relied on varieties with varying levels of partial resistance. Partial resistance is effective in suppressing disease, but continued exposure can result in an increase in pathogen aggressiveness that threatens durability of the resistance to P. nicotianae. Aggressiveness components in P. nicotianae were characterized following adaptation on two sources of partial resistance, Fla 301 and the Wz genomic region from Nicotiana rustica. An aggressive isolate of the two major races of P. nicotianae, race 0 and race 1, was adapted for either one/two or five/six generations on the two resistance sources, giving four sets of isolates based on race, number of generations of adaptation, and source of resistance. Across the four sets of isolates, adapted isolates infected higher proportions of tobacco root tips, produced more sporangia per infected root tip, and caused larger lesions than their respective nonadapted isolates of the same race and from the same resistance source. Adapted isolates also produced more aggressive zoospore progeny than the nonadapted isolates. Adaptation to partial resistance involves multiple aggressiveness components and results in the increased aggressiveness observed for P. nicotianae. These results improve our knowledge on the nature of P. nicotianae adaptation to partial resistance in tobacco and indicate that different resistance sources are likely to select for similar aggressiveness components in the pathogen.
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Affiliation(s)
- Jing Jin
- Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, NC 27695
| | - H David Shew
- Department of Entomology and Plant Pathology, North Carolina State University, Raleigh, NC 27695
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Francki MG, Walker E, McMullan CJ, Morris WG. Evaluation of Septoria Nodorum Blotch (SNB) Resistance in Glumes of Wheat ( Triticum aestivum L.) and the Genetic Relationship With Foliar Disease Response. Front Genet 2021; 12:681768. [PMID: 34267781 PMCID: PMC8276050 DOI: 10.3389/fgene.2021.681768] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2021] [Accepted: 06/07/2021] [Indexed: 11/13/2022] Open
Abstract
Septoria nodorum blotch (SNB) is a necrotrophic disease of wheat prominent in some parts of the world, including Western Australia (WA) causing significant losses in grain yield. The genetic mechanisms for resistance are complex involving multiple quantitative trait loci. In order to decipher comparable or independent regulation, this study identified the genetic control for glume compared to foliar resistance across four environments in WA against 37 different isolates. High proportion of the phenotypic variation across environments was contributed by genotype (84.0% for glume response and 82.7% for foliar response) with genotype-by-environment interactions accounting for a proportion of the variation for both glume and foliar response (14.7 and 16.2%, respectively). Despite high phenotypic correlation across environments, most of the eight and 14 QTL detected for glume and foliar resistance using genome wide association analysis (GWAS), respectively, were identified as environment-specific. QTL for glume and foliar resistance neither co-located nor were in LD in any particular environment indicating autonomous genetic mechanisms control SNB response in adult plants, regulated by independent biological mechanisms and influenced by significant genotype-by- environment interactions. Known Snn and Tsn loci and QTL were compared with 22 environment-specific QTL. None of the eight QTL for glume or the 14 for foliar response were co-located or in linkage disequilibrium with Snn and only one foliar QTL was in LD with Tsn loci on the physical map. Therefore, glume and foliar response to SNB in wheat is regulated by multiple environment-specific loci which function independently, with limited influence of known NE-Snn interactions for disease progression in Western Australian environments. Breeding for stable resistance would consequently rely on recurrent phenotypic selection to capture and retain favorable alleles for both glume and foliar resistance relevant to a particular environment.
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Affiliation(s)
- Michael G Francki
- Department of Primary Industries and Regional Development, South Perth, WA, Australia.,State Agricultural Biotechnology Centre, Murdoch University, Murdoch, WA, Australia
| | - Esther Walker
- Department of Primary Industries and Regional Development, South Perth, WA, Australia.,State Agricultural Biotechnology Centre, Murdoch University, Murdoch, WA, Australia
| | | | - W George Morris
- Department of Primary Industries and Regional Development, South Perth, WA, Australia
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Botha AM. Fast developing Russian wheat aphid biotypes remains an unsolved enigma. CURRENT OPINION IN INSECT SCIENCE 2021; 45:42-52. [PMID: 33359167 DOI: 10.1016/j.cois.2020.12.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Revised: 12/05/2020] [Accepted: 12/07/2020] [Indexed: 06/12/2023]
Abstract
Diuraphis noxia, commonly known as the Russian wheat aphid, is an economically important cereal pest species, highly invasive and reproduces mostly asexually. Remarkably, many new virulent populations continue to develop, despite the lack of genetic diversity in the aphid. Russian wheat aphid is a phloem feeder and is therefore engaged in a continuous arms battle with its cereal host, with the acquisition of virulence central to the breakdown of host resistance. In the review, most attention is given to recent topics about mechanisms and strategies whereby the aphid acquires virulence against its host, with special reference given to the role of noncoding RNA elements, bacteria, and the epigenetic pathway in possibly directing virulence.
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Affiliation(s)
- Anna-Maria Botha
- Genetics Department, Stellenbosch University, Private Bag X1, Matieland, Stellenbosch 7601, South Africa.
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Sacristán S, Goss EM, Eves-van den Akker S. How Do Pathogens Evolve Novel Virulence Activities? MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2021; 34:576-586. [PMID: 33522842 DOI: 10.1094/mpmi-09-20-0258-ia] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
This article is part of the Top 10 Unanswered Questions in MPMI invited review series.We consider the state of knowledge on pathogen evolution of novel virulence activities, broadly defined as anything that increases pathogen fitness with the consequence of causing disease in either the qualitative or quantitative senses, including adaptation of pathogens to host immunity and physiology, host species, genotypes, or tissues, or the environment. The evolution of novel virulence activities as an adaptive trait is based on the selection exerted by hosts on variants that have been generated de novo or arrived from elsewhere. In addition, the biotic and abiotic environment a pathogen experiences beyond the host may influence pathogen virulence activities. We consider host-pathogen evolution, host range expansion, and external factors that can mediate pathogen evolution. We then discuss the mechanisms by which pathogens generate and recombine the genetic variation that leads to novel virulence activities, including DNA point mutation, transposable element activity, gene duplication and neofunctionalization, and genetic exchange. In summary, if there is an (epi)genetic mechanism that can create variation in the genome, it will be used by pathogens to evolve virulence factors. Our knowledge of virulence evolution has been biased by pathogen evolution in response to major gene resistance, leaving other virulence activities underexplored. Understanding the key driving forces that give rise to novel virulence activities and the integration of evolutionary concepts and methods with mechanistic research on plant-microbe interactions can help inform crop protection.[Formula: see text] Copyright © 2021 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.
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Affiliation(s)
- Soledad Sacristán
- Centro de Biotecnología y Genómica de Plantas, Universidad Politécnica de Madrid (UPM)-Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Campus Montegancedo-UPM, 28223-Pozuelo de Alarcón (Madrid), Spain
- Departamento de Biotecnología-Biología Vegetal, Escuela Técnica Superior de Ingeniería Agronómica, Alimentaria y de Biosistemas, Universidad Politécnica de Madrid, 28040-Madrid, Spain
| | - Erica M Goss
- Department of Plant Pathology and Emerging Pathogens Institute, University of Florida, Gainesville, Florida, U.S.A
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Laurent B, Moinard M, Spataro C, Chéreau S, Zehraoui E, Blanc R, Lasserre P, Ponts N, Foulongne-Oriol M. QTL mapping in Fusarium graminearum identified an allele of FgVe1 involved in reduced aggressiveness. Fungal Genet Biol 2021; 153:103566. [PMID: 33991664 DOI: 10.1016/j.fgb.2021.103566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Revised: 05/04/2021] [Accepted: 05/05/2021] [Indexed: 10/21/2022]
Abstract
Fusarium graminearum is one of the most frequent causal agents of the Fusarium Head Blight, a cereal disease spread throughout the world, reducing grain production and quality. F. graminearum isolates are genetically and phenotypically highly diverse. Notably, remarkable variations of aggressiveness between isolates have been observed, which could reflect an adaptive potential of this pathogen. In this study, we aimed to characterize the genetic basis of aggressiveness variation observed in an F1 population (n = 94), for which genome sequences of both parental strains are available. Aggressiveness was assessed by a panel of in planta and in vitro proxies during two phenotyping trials including, among others, disease severity and mycotoxin accumulation in wheat spike. One major and single QTL was mapped for all the traits measured, on chromosome I, that explained up to 90% of the variance for disease severity. The confidence interval at the QTL spanned 1.2 Mb and contained 428 genes on the reference genome. Of these, four candidates were selected based on the postulate that a non-synonymous mutation affecting protein function may be responsible for phenotypic differences. Finally, a new mutation was identified and functionally validated in the gene FgVe1, coding for a velvet protein known to be involved in pathogenicity and secondary metabolism production in several fungi.
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Affiliation(s)
| | | | | | | | - Enric Zehraoui
- INRAE, MycSA, F-33882 Villenave d'Ornon, France; Université de Bordeaux, INRAE, EGFV, F-33882 Villenave d'Ornon, France
| | - Richard Blanc
- INRAE, UCA, UMR 1095 GDEC, F-63100 Clermont-Ferrand, France
| | | | - Nadia Ponts
- INRAE, MycSA, F-33882 Villenave d'Ornon, France
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Abstract
Plant pathogens can adapt to quantitative resistance, eroding its effectiveness. The aim of this work was to reveal the genomic basis of adaptation to such a resistance in populations of the fungus Pseudocercospora fijiensis, a major devastating pathogen of banana, by studying convergent adaptation on different cultivars. Samples from P. fijiensis populations showing a local adaptation pattern on new banana hybrids with quantitative resistance were compared, based on a genome scan approach, with samples from traditional and more susceptible cultivars in Cuba and the Dominican Republic. Whole-genome sequencing of pools of P. fijiensis isolates (pool-seq) sampled from three locations per country was conducted according to a paired population design. The findings of different combined analyses highly supported the existence of convergent adaptation on the study cultivars between locations within but not between countries. Five to six genomic regions involved in this adaptation were detected in each country. An annotation analysis and available biological data supported the hypothesis that some genes within the detected genomic regions may play a role in quantitative pathogenicity, including gene regulation. The results suggested that the genetic basis of fungal adaptation to quantitative plant resistance is at least oligogenic, while highlighting the existence of specific host-pathogen interactions for this kind of resistance.IMPORTANCE Understanding the genetic basis of pathogen adaptation to quantitative resistance in plants has a key role to play in establishing durable strategies for resistance deployment. In this context, a population genomic approach was developed for a major plant pathogen (the fungus Pseudocercospora fijiensis causing black leaf streak disease of banana) whereby samples from new resistant banana hybrids were compared with samples from more susceptible conventional cultivars in two countries. A total of 11 genomic regions for which there was strong evidence of selection by quantitative resistance were detected. An annotation analysis and available biological data supported the hypothesis that some of the genes within these regions may play a role in quantitative pathogenicity. These results suggested a polygenic basis of quantitative pathogenicity in this fungal pathogen and complex molecular plant-pathogen interactions in quantitative disease development involving several genes on both sides.
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In Vitro and In Planta Studies on Temperature Adaptation of Exserohilum turcicum Isolates from Maize in Europe and South America. Pathogens 2021; 10:pathogens10020154. [PMID: 33540950 PMCID: PMC7913211 DOI: 10.3390/pathogens10020154] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Revised: 01/27/2021] [Accepted: 01/27/2021] [Indexed: 11/17/2022] Open
Abstract
Northern Corn Leaf Blight (NCLB) is a fungal leaf disease in maize caused by Exserohilum turcicum. NCLB occurs worldwide, from tropical to temperate zones raising the question about plasticity of temperature adaptation of local isolates of the pathogen. Seven isolates of E. turcicum originating from South America and seven from Europe were compared for their response to temperature variations in vitro and in vivo between 15 and 30 °C. In vitro, isolates originating from Europe and South America significantly differed in mycelial growth rate at 30 °C and in sporulation at 25 °C and 30 °C. Aggressiveness of E. turcicum isolates was evaluated on three susceptible maize cultivars (maize lines B37, Sus1 and the German hybrid Niklas) under different day/night temperature regimes (15/10 °C, 20/15 °C, 25/20 °C, or 30/25 °C) with a photoperiod of 14 h. Aggressiveness, recorded as area under the disease progress curve (AUDPC), of South American isolates was higher than for European isolates at 15 °C, 20 °C and 25 °C, and for sporulation in vivo in all temperatures. In general, aggressiveness components were most influenced by temperature. Therefore, multivariate analysis was performed with aggressiveness component data at 30 °C, which expressed the highest number of variables with significant differences between isolate origins. According to their aggressiveness, European and South American isolates can be grouped separately, demonstrating that South American isolates are better adapted to higher temperatures and display a higher level of aggressiveness under similar conditions than European isolates from a cool climate. It is concluded that plasticity of temperature adaptation in E. turcicum populations is relatively large and allowed E. turcicum to follow the recent expansion of maize cultivation into cool climate zones in Europe. However, our data suggest that adaptation to higher temperature is likely to increase aggressiveness of NCLB on maize in cooler climate zones when experiencing further climate warming. This plasticity in adaptation to environmental conditions of E. turcicum may also hamper the success of breeding programs as it may decrease the durability of resistance.
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Maupetit A, Fabre B, Pétrowski J, Andrieux A, De Mita S, Frey P, Halkett F, Hayden KJ. Evolution of morphological but not aggressiveness-related traits following a major resistance breakdown in the poplar rust fungus, Melampsora larici-populina. Evol Appl 2021; 14:513-523. [PMID: 33664791 PMCID: PMC7896724 DOI: 10.1111/eva.13136] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Revised: 09/01/2020] [Accepted: 09/02/2020] [Indexed: 11/29/2022] Open
Abstract
Crop varieties carrying qualitative resistance to targeted pathogens lead to strong selection pressure on parasites, often resulting in resistance breakdown. It is well known that qualitative resistance breakdowns modify pathogen population structure but few studies have analyzed the consequences on their quantitative aggressiveness-related traits. The aim of this study was to characterize the evolution of these traits following a resistance breakdown in the poplar rust fungus, Melampsora larici-populina. We based our experiment on three temporal populations sampled just before the breakdown event, immediately after and four years later. First, we quantified phenotypic differences among populations for a set of aggressiveness traits on a universally susceptible cultivar (infection efficiency, latent period, lesion size, mycelium quantity, and sporulation rate) and one morphological trait (mean spore volume). Then, we estimated heritability to establish which traits could be subjected to adaptive evolution and tested for evidence of selection. Our results revealed significant changes in the morphological trait but no variation in aggressiveness traits. By contrast, recent works have demonstrated that quantitative resistance (initially assumed more durable) could be eroded and lead to increased aggressiveness. Hence, this study is one example suggesting that the use of qualitative resistance may be revealed to be less detrimental to long-term sustainable crop production.
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Affiliation(s)
- Agathe Maupetit
- INRAEUniversité de LorraineNancyFrance
- Royal Botanical Garden EdinburghEdinburghUK
- Present address:
IFREMER, Physiology and Biotechnology of Algae LaboratoryNantesFrance
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Dutta A, Croll D, McDonald BA, Barrett LG. Maintenance of variation in virulence and reproduction in populations of an agricultural plant pathogen. Evol Appl 2021; 14:335-347. [PMID: 33664780 PMCID: PMC7896723 DOI: 10.1111/eva.13117] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Revised: 07/04/2020] [Accepted: 08/13/2020] [Indexed: 11/27/2022] Open
Abstract
Genetic diversity within pathogen populations is critically important for predicting pathogen evolution, disease outcomes and prevalence. However, we lack a good understanding of the processes maintaining genetic variation and constraints on pathogen life-history evolution. Here, we analysed interactions between 12 wheat host genotypes and 145 strains of Zymoseptoria tritici from five global populations to investigate the evolution and maintenance of variation in pathogen virulence and reproduction. We found a strong positive correlation between virulence (amount of leaf necrosis) and reproduction (pycnidia density within lesions), with substantial variation in both traits maintained within populations. On average, highly virulent isolates exhibited higher reproduction, which might increase transmission potential in agricultural fields planted to homogeneous hosts at a high density. We further showed that pathogen strains with a narrow host range (i.e. specialists) for reproduction were on average less virulent, and those with a broader host range (i.e. generalists) were on average less fecund on a given specific host. These costs associated with adaptation to different host genotypes might constrain the emergence of generalists by disrupting the directional evolution of virulence and fecundity. We conclude that selection favouring pathogen strains that are virulent across diverse hosts, coupled with selection that maximizes fecundity on specific hosts, may explain the maintenance of these pathogenicity traits within and among populations.
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Affiliation(s)
- Anik Dutta
- Plant PathologyInstitute of Integrative BiologyETH ZurichZurichSwitzerland
| | - Daniel Croll
- Laboratory of Evolutionary GeneticsInstitute of BiologyUniversity of NeuchâtelNeuchâtelSwitzerland
| | - Bruce A. McDonald
- Plant PathologyInstitute of Integrative BiologyETH ZurichZurichSwitzerland
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Vall-Llaura N, Giné-Bordonaba J, Usall J, Larrigaudière C, Teixidó N, Torres R. Ethylene biosynthesis and response factors are differentially modulated during the interaction of peach petals with Monilinia laxa or Monilinia fructicola. PLANT SCIENCE : AN INTERNATIONAL JOURNAL OF EXPERIMENTAL PLANT BIOLOGY 2020; 299:110599. [PMID: 32900437 DOI: 10.1016/j.plantsci.2020.110599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2020] [Revised: 06/25/2020] [Accepted: 07/12/2020] [Indexed: 06/11/2023]
Abstract
Monilinia spp. may infect stone fruit at any growth stage, although susceptibility to brown rot depends on both host properties and climatological conditions. This said, no studies deciphering the host response in the interaction between peach blossoms and Monilinia spp. are yet available. This study presents an in-depth characterization of the role of ethylene in the interaction of 'Merrill O'Henry' peach petals (Prunus persica (L.) Batch) with Monilinia laxa and M. fructicola. We investigated the physiological responses of the host and the fungi to the application of ethylene and 1-methylcyclopropene (1-MCP) as well as the molecular patterns associated with the biosynthetic and ethylene-dependent responses during the interaction of both Monilinia species with the host. The incidence of both species was differentially affected by 1-MCP and ethylene; M. laxa was favoured by the enhanced host ethylene production associated with the treatments whereas M. fructicola reduced its infection capacity. Such differences were host-dependent as treatments did not affect growth or colony morphology of Monilinia spp. Besides, host ethylene production was altered in M. laxa inoculated petals, either by the fungus or the host itself. Molecular analysis revealed some important ERFs that could be involved in the different ability of both species to activate a cascade response of peach petals against these pathogens.
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Affiliation(s)
- Núria Vall-Llaura
- XaRTA-Postharvest, Institute of Agrifood Research and Technology (IRTA), Edifici Fruitcentre, Parc Científic i Tecnològic Agroalimentari de Lleida, Parc de Gardeny, 25003 Lleida, Catalonia, Spain.
| | - Jordi Giné-Bordonaba
- XaRTA-Postharvest, Institute of Agrifood Research and Technology (IRTA), Edifici Fruitcentre, Parc Científic i Tecnològic Agroalimentari de Lleida, Parc de Gardeny, 25003 Lleida, Catalonia, Spain.
| | - Josep Usall
- XaRTA-Postharvest, Institute of Agrifood Research and Technology (IRTA), Edifici Fruitcentre, Parc Científic i Tecnològic Agroalimentari de Lleida, Parc de Gardeny, 25003 Lleida, Catalonia, Spain.
| | - Christian Larrigaudière
- XaRTA-Postharvest, Institute of Agrifood Research and Technology (IRTA), Edifici Fruitcentre, Parc Científic i Tecnològic Agroalimentari de Lleida, Parc de Gardeny, 25003 Lleida, Catalonia, Spain.
| | - Neus Teixidó
- XaRTA-Postharvest, Institute of Agrifood Research and Technology (IRTA), Edifici Fruitcentre, Parc Científic i Tecnològic Agroalimentari de Lleida, Parc de Gardeny, 25003 Lleida, Catalonia, Spain.
| | - Rosario Torres
- XaRTA-Postharvest, Institute of Agrifood Research and Technology (IRTA), Edifici Fruitcentre, Parc Científic i Tecnològic Agroalimentari de Lleida, Parc de Gardeny, 25003 Lleida, Catalonia, Spain.
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Francki MG, Walker E, McMullan CJ, Morris WG. Multi-Location Evaluation of Global Wheat Lines Reveal Multiple QTL for Adult Plant Resistance to Septoria Nodorum Blotch (SNB) Detected in Specific Environments and in Response to Different Isolates. FRONTIERS IN PLANT SCIENCE 2020; 11:771. [PMID: 32655592 PMCID: PMC7325896 DOI: 10.3389/fpls.2020.00771] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2020] [Accepted: 05/15/2020] [Indexed: 05/26/2023]
Abstract
The slow rate of genetic gain for improving resistance to Septoria nodorum blotch (SNB) is due to the inherent complex interactions between host, isolates, and environments. Breeding for improved SNB resistance requires evaluation and selection of wheat genotypes consistently expressing low SNB response in different target production environments. The study focused on evaluating 232 genotypes from global origins for resistance to SNB in the flag leaf expressed in different Western Australian environments. The aim was to identify resistant donor germplasm against historical and contemporary pathogen isolates and enhance our knowledge of the genetic basis of genotype-by-environment interactions for SNB response. Australian wheat varieties, inbred lines from Centro Internacional de Mejoramiento de Maiz y Trigo (CIMMYT), and International Center for Agricultural Research in the Dry Areas (ICARDA), and landraces from discrete regions of the world showed low to moderate phenotypic correlation for disease response amongst genotypes when evaluated with historical and contemporary isolates at two locations across 3 years in Western Australia (WA). Significant (P < 0.001) genotype-by-environment interactions were detected regardless of same or different isolates used as an inoculum source. Joint regression analysis identified 19 genotypes that consistently expressed low disease severity under infection with different isolates in multi-locations. The CIMMYT inbred lines, 30ZJN09 and ZJN12 Qno25, were particularly pertinent as they had low SNB response and highest trait stability at two locations across 3 years. Genome wide association studies detected 20 QTL associated with SNB resistance on chromosomes 1A, 1B, 4B, 5A, 5B, 6A, 7A, 7B, and 7D. QTL on chromosomes 1B and 5B were previously reported in similar genomic regions. Multiple QTL were identified on 1B, 5B, 6A, and 5A and detected in response to SNB infection against different isolates and specific environments. Known SnTox-Snn interactions were either not evident or variable across WA environments and SNB response may involve other multiple complex biological mechanisms.
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Affiliation(s)
- Michael G. Francki
- Department of Primary Industries and Regional Development, South Perth, WA, Australia
- State Agricultural Biotechnology Centre, Murdoch University, Murdoch, WA, Australia
| | - Esther Walker
- Department of Primary Industries and Regional Development, South Perth, WA, Australia
- State Agricultural Biotechnology Centre, Murdoch University, Murdoch, WA, Australia
| | | | - W. George Morris
- Department of Primary Industries and Regional Development, South Perth, WA, Australia
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Rahman A, Doohan F, Mullins E. Quantification of In Planta Zymoseptoria tritici Progression Through Different Infection Phases and Related Association with Components of Aggressiveness. PHYTOPATHOLOGY 2020; 110:1208-1215. [PMID: 32133920 DOI: 10.1094/phyto-09-19-0339-r] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
In planta growth of Zymoseptoria tritici, causal agent of Septoria tritici blotch of wheat, during the infection process has remained an understudied topic due to the long symptomless latent period before the emergence of fruiting bodies. In this study, we attempted to understand the relationship between in planta growth of Z. tritici relative to the primary components of aggressiveness, i.e., latent period and pycnidia coverage in regard to contrasting host resistance. We tested isolates collected from Ireland against the susceptible cultivar Gallant and cultivar Stigg, which has strong partial resistance. A clear isolate-host interaction effect (F = 3.018; P = 0.005, and F = 6.008; P < 0.001) for latent period and pycnidia coverage, respectively, was identified. Furthermore, during the early infection phase of latency from 5 to 11 days postinoculation (dpi), in planta growth rate of fungal biomass was significantly (F = 30.06; P < 0.001) more affected by host resistance than isolate specificity (F = 1.27; P = 0.27), indicating the importance of host resistance in the early infection phase. In planta Z. tritici growth rates in cultivar Gallant spiked between 11 and 16 dpi followed by a continuous fall onward, whereas in cultivar Stigg it was slowly progressive in nature. From correlation and regression analysis, we found that the in planta growth rate preceding the average latent period of cultivar Gallant has more influence on latency duration and pycnidia production. Likewise, correlation between component of aggressiveness and in planta growth rate of pathogen supports our understanding of aggressiveness to be driven by the pathogen's multiplication capacity within host tissue.
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Affiliation(s)
- Atikur Rahman
- Crop Science Department, Teagasc, Oakpark, Carlow, R93 XE12, Ireland
- School of Biological and Environmental Sciences, UCD Earth Institute and UCD Institute of Food and Health, University College of Dublin, Dublin, D04 V1W8, Ireland
| | - Fiona Doohan
- School of Biological and Environmental Sciences, UCD Earth Institute and UCD Institute of Food and Health, University College of Dublin, Dublin, D04 V1W8, Ireland
| | - Ewen Mullins
- Crop Science Department, Teagasc, Oakpark, Carlow, R93 XE12, Ireland
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Genus-level change in aggressiveness with continuous invasions: a phylogenetically-informed Bayesian quantile regression. Biol Invasions 2020. [DOI: 10.1007/s10530-020-02229-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Précigout PA, Robert C, Claessen D. Adaptation of Biotrophic Leaf Pathogens to Fertilization-Mediated Changes in Plant Traits: A Comparison of the Optimization Principle to Invasion Fitness. PHYTOPATHOLOGY 2020; 110:1039-1048. [PMID: 31928514 DOI: 10.1094/phyto-08-19-0317-r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
One of the conclusions of evolutionary ecology applied to agroecosystem management is that sustainable disease management strategies must be adaptive to overcome the immense adaptive potential of crop pathogens. In this context, knowledge of how pathogens adapt to changes in cultural practices is necessary. In this article we address the issue of the evolutionary response of biotrophic crop pathogens to changes in fertilization practices. For this purpose, we compare predictions of latent period evolution based on three empirical fitness measures (seasonal spore production, within-season exponential growth rate, and area under disease progress curves [AUDPCs]) with predictions based on the concept of invasion fitness from adaptive dynamics. We use pairwise invisibility plots to identify the evolutionarily stable strategies (ESSs) of the pathogen latent period. We find that the ESS latent period is in between the latent periods that maximize the seasonal spore production and the within-season exponential growth rate of the pathogen. The latent periods that maximize the AUDPC are similar to those of the ESS latent periods. The AUDPC may therefore be a critical variable to determine the issue of between-strain competition and shape pathogen evolution.
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Affiliation(s)
- Pierre-Antoine Précigout
- UMR EcoSys, INRAe-AgroParisTech, 78850 Thiverval-Grignon, France
- Institut de Biologie de l'Ecole Normale Supérieure, CNRS-ENS-INSERM UMR8197, Ecole Normale Supérieure, 75005 Paris, France
| | - Corinne Robert
- UMR EcoSys, INRAe-AgroParisTech, 78850 Thiverval-Grignon, France
| | - David Claessen
- Institut de Biologie de l'Ecole Normale Supérieure, CNRS-ENS-INSERM UMR8197, Ecole Normale Supérieure, 75005 Paris, France
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40
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Gold KM, Townsend PA, Larson ER, Herrmann I, Gevens AJ. Contact Reflectance Spectroscopy for Rapid, Accurate, and Nondestructive Phytophthora infestans Clonal Lineage Discrimination. PHYTOPATHOLOGY 2020; 110:851-862. [PMID: 31880984 DOI: 10.1094/phyto-08-19-0294-r] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Populations of Phytophthora infestans, the oomycete causal agent of potato late blight in the United States, are predominantly asexual, and isolates are characterized by clonal lineage or asexual descendants of a single genotype. Current tools for clonal lineage identification are time consuming and require laboratory equipment. We previously found that foliar spectroscopy can be used for high-accuracy pre- and postsymptomatic detection of P. infestans infections caused by clonal lineages US-08 and US-23. In this work, we found subtle but distinct differences in spectral responses of potato foliage infected by these clonal lineages in both growth-chamber time-course experiments (12- to 24-h intervals over 5 days) and naturally infected samples from commercial production fields. In both settings, we measured continuous visible to shortwave infrared reflectance (400 to 2,500 nm) on leaves using a portable spectrometer with contact probe. We consistently discriminated between infections caused by the two clonal lineages across all stages of disease progression using partial least squares (PLS) discriminant analysis, with total accuracies ranging from 88 to 98%. Three-class random forest differentiation between control, US-08, and US-23 yielded total discrimination accuracy ranging from 68 to 76%. Differences were greatest during presymptomatic infection stages and progressed toward uniformity as symptoms advanced. Using PLS-regression trait models, we found that total phenolics, sugar, and leaf mass per area were different between lineages. Shortwave infrared wavelengths (>1,100 nm) were important for clonal lineage differentiation. This work provides a foundation for future use of hyperspectral sensing as a nondestructive tool for pathovar differentiation.
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Affiliation(s)
- Kaitlin M Gold
- Department of Plant Pathology, University of Wisconsin-Madison, 1630 Linden Drive, Madison, WI 53706, U.S.A
| | - Philip A Townsend
- Department of Forest and Wildlife Ecology, University of Wisconsin-Madison, 1630 Linden Drive, Madison, WI 53706, U.S.A
| | - Eric R Larson
- Department of Plant Pathology, University of Wisconsin-Madison, 1630 Linden Drive, Madison, WI 53706, U.S.A
| | - Ittai Herrmann
- The Robert H. Smith Institute for Plant Sciences and Genetics in Agriculture, The Hebrew University of Jerusalem, P.O. Box 12, Rehovot 7610001, Israel
| | - Amanda J Gevens
- Department of Plant Pathology, University of Wisconsin-Madison, 1630 Linden Drive, Madison, WI 53706, U.S.A
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Abstract
Among the thousands of rust species described, many are known for their devastating effects on their hosts, which include major agriculture crops and trees. Hence, for over a century, these basidiomycete pathogenic fungi have been researched and experimented with. However, due to their biotrophic nature, they are challenging organisms to work with and, needing their hosts for propagation, represent pathosystems that are not easily experimentally accessible. Indeed, efforts to perform genetics have been few and far apart for the rust fungi, though one study performed in the 1940s was famously instrumental in formulating the gene-for-gene hypothesis describing pathogen-host interactions. By taking full advantage of the molecular genetic tools developed in the 1980s, research on many plant pathogenic microbes thrived, yet similar work on the rusts remained very challenging though not without some successes. However, the genomics era brought real breakthrough research for the biotrophic fungi and with innovative experimentation and the use of heterologous systems, molecular genetic analyses over the last 2 decades have significantly advanced our insight into the function of many rust fungus genes and their role in the interaction with their hosts. This has allowed optimizing efforts for resistance breeding and the design and testing of various novel strategies to reduce the devastating diseases they cause.
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Affiliation(s)
- Guus Bakkeren
- Agriculture and Agri-Food Canada, Summerland Research & Development Centre, 4200 Hwy 97, Summerland, BC, Canada V0H 1Z0
| | - Les J Szabo
- U.S. Department of Agriculture-Agriculture Research Service, Cereal Disease Laboratory and University of Minnesota, 1551 Lindig Street, St. Paul, MN 55108, U.S.A
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Le May C, Montarry J, Morris CE, Frenkel O, Ravigné V. Editorial: Plant Pathogen Life-History Traits and Adaptation to Environmental Constraints. FRONTIERS IN PLANT SCIENCE 2020; 10:1730. [PMID: 32038694 PMCID: PMC6993043 DOI: 10.3389/fpls.2019.01730] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2019] [Accepted: 12/09/2019] [Indexed: 05/31/2023]
Affiliation(s)
- Christophe Le May
- IGEPP, INRA, Agrocampus-Ouest, Université de Rennes 1, Le Rheu, France
| | - Josselin Montarry
- IGEPP, INRA, Agrocampus-Ouest, Université de Rennes 1, Le Rheu, France
| | | | - Omer Frenkel
- Agricultural Research Organization, Volcani Center, Rishon LeZion, Israel
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Fabre F, Bormann J, Urbach S, Roche S, Langin T, Bonhomme L. Unbalanced Roles of Fungal Aggressiveness and Host Cultivars in the Establishment of the Fusarium Head Blight in Bread Wheat. Front Microbiol 2019; 10:2857. [PMID: 31921038 PMCID: PMC6917580 DOI: 10.3389/fmicb.2019.02857] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2019] [Accepted: 11/25/2019] [Indexed: 01/07/2023] Open
Abstract
Fusarium head blight (FHB), caused mainly by Fusarium graminearum, is the foremost destructive disease of cereals worldwide. Effector-like molecules produced by F. graminearum play key roles in the infection process and are assumed to be one of the essential components of the pathogen’s aggressiveness. However, their nature and role in the disease are still largely misunderstood. As a mean to provide relevant information about the molecular determinism of F. graminearum aggressiveness, we surveyed three F. graminearum strains on three wheat cultivars contrasted by their susceptibility to FHB. F. graminearum strains revealed large differences in aggressiveness which were mostly unchanged when facing hosts of contrasted susceptibility, suggesting that their behavior rely on intrinsic determinants. Surveying the fungal mass progress and the mycotoxin production rate in the spikes did not evidence any simple relationship with aggressiveness differences, while clues were found through a qualitative and quantitative characterization of the three strain proteomes established in planta especially with regards to early synthesized putative effectors. Independently of the wheat cultivar, the three F. graminearum strains produced systematically the same protein set during the infection but substantial differences in their abundance enabled the categorization of fungal aggressiveness. Overall, our findings show that the contrasts in F. graminearum aggressiveness were not based on the existence of strain-specific molecules but rather on the ability of the strain to ensure their sufficient accumulation. Protein abundance variance was mostly driven by the strain genetics and part was also influenced by the host cultivar but strain by cultivar interactions were marginally detected, depicting that strain-specific protein accumulations did not depend on the host cultivar. All these data provide new knowledge on fungal aggressiveness determinants and provide a resourceful repertoire of candidate effector proteins to guide further research.
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Affiliation(s)
- Francis Fabre
- Université Clermont Auvergne, INRAE, UMR 1095 Genetics, Diversity and Ecophysiology of Cereals, Clermont-Ferrand, France
| | - Joerg Bormann
- Department of Molecular Phytopathology, Institute of Plant Science and Microbiology, University of Hamburg, Hamburg, Germany
| | - Serge Urbach
- Functional Proteomics Platform, Institute of Functional Genomics, CNRS UMR 5203 INSERM U661, Montpellier, France
| | - Sylvie Roche
- INRAE, Unité Experimentale 1375, Phénotypage au Champs des Céréales (PHACC), Clermont-Ferrand, France
| | - Thierry Langin
- Université Clermont Auvergne, INRAE, UMR 1095 Genetics, Diversity and Ecophysiology of Cereals, Clermont-Ferrand, France
| | - Ludovic Bonhomme
- Université Clermont Auvergne, INRAE, UMR 1095 Genetics, Diversity and Ecophysiology of Cereals, Clermont-Ferrand, France
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David O, van Frank G, Goldringer I, Rivière P, Turbet Delof M. Bayesian inference of natural selection from spatiotemporal phenotypic data. Theor Popul Biol 2019; 131:100-109. [PMID: 31812618 DOI: 10.1016/j.tpb.2019.11.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Revised: 10/04/2019] [Accepted: 11/20/2019] [Indexed: 10/25/2022]
Abstract
Spatiotemporal variations of natural selection may influence the evolution of various features of organisms such as local adaptation or specialisation. This article develops a method for inferring how selection varies between locations and between generations from phenotypic data. It is assumed that generations are non-overlapping and that individuals reproduce by selfing or asexually. A quantitative genetics model taking account of the effects of stabilising natural selection, the environment and mutation on phenotypic means and variances is developed. Explicit results on the evolution of populations are derived and used to develop a Bayesian inference method. The latter is applied to simulated data and to data from a wheat participatory plant breeding programme. It has some ability to infer evolutionary parameters, but estimates may be sensitive to prior distributions, for example when phenotypic time series are short and when environmental effects are large. In such cases, sensitivity to prior distributions may be reported or more data may be collected.
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Affiliation(s)
- Olivier David
- MaIAGE, INRA, Université Paris-Saclay, 78350, Jouy-en-Josas, France.
| | - Gaëlle van Frank
- Génétique Quantitative et Evolution - Le Moulon, INRA, Université Paris-Saclay, Université Paris-Sud, CNRS, AgroParisTech, 91190, Gif-sur-Yvette, France
| | - Isabelle Goldringer
- Génétique Quantitative et Evolution - Le Moulon, INRA, Université Paris-Saclay, Université Paris-Sud, CNRS, AgroParisTech, 91190, Gif-sur-Yvette, France
| | | | - Michel Turbet Delof
- Génétique Quantitative et Evolution - Le Moulon, INRA, Université Paris-Saclay, Université Paris-Sud, CNRS, AgroParisTech, 91190, Gif-sur-Yvette, France
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45
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Leclerc M, Clément JAJ, Andrivon D, Hamelin FM. Assessing the effects of quantitative host resistance on the life-history traits of sporulating parasites with growing lesions. Proc Biol Sci 2019; 286:20191244. [PMID: 31575367 DOI: 10.1098/rspb.2019.1244] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Assessing life-history traits of parasites on resistant hosts is crucial in evolutionary ecology. In the particular case of sporulating pathogens with growing lesions, phenotyping is difficult because one needs to disentangle properly pathogen spread from sporulation. By considering Phytophthora infestans on potato, we use mathematical modelling to tackle this issue and refine the assessment of pathogen response to quantitative host resistance. We elaborate a parsimonious leaf-scale model by convolving a lesion growth model and a sporulation function, after a latency period. This model is fitted to data obtained on two isolates inoculated on three cultivars with contrasted resistance level. Our results confirm a significant host-pathogen interaction on the various estimated traits, and a reduction of both pathogen spread and spore production, induced by host resistance. Most interestingly, we highlight that quantitative resistance also changes the sporulation function, the mode of which is significantly time-lagged. This alteration of the infectious period distribution on resistant hosts may have strong impacts on the dynamics of parasite populations, and should be considered when assessing the durability of disease control tactics based on plant resistance management. This inter-disciplinary work also supports the relevance of mechanistic models for analysing phenotypic data of plant-pathogen interactions.
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Affiliation(s)
- Melen Leclerc
- IGEPP, INRA, Agrocampus Ouest, Université Rennes 1, Le Rheu, France
| | | | - Didier Andrivon
- IGEPP, INRA, Agrocampus Ouest, Université Rennes 1, Le Rheu, France
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46
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Cowger C, Brown JKM. Durability of Quantitative Resistance in Crops: Greater Than We Know? ANNUAL REVIEW OF PHYTOPATHOLOGY 2019; 57:253-277. [PMID: 31206351 DOI: 10.1146/annurev-phyto-082718-100016] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Quantitative resistance (QR) to crop diseases has usually been much more durable than major-gene, effector-triggered resistance. It has been observed that the effectiveness of some QR has eroded as pathogens adapt to it, especially when deployment is extensive and epidemics occur regularly, but it generally declines more slowly than effector-triggered resistance. Changes in aggressiveness and specificity of diverse pathogens on cultivars with QR have been recorded, along with experimental data on fitness costs of pathogen adaptation to QR, but there is little information about molecular mechanisms of adaptation. Some QR has correlated or antagonistic effects on multiple diseases. Longitudinal data on cultivars' disease ratings in trials over several years can be used to assess the significance of QR for durable resistance in crops. It is argued that published data likely underreport the durability of QR, owing to publication bias. The implications of research on QR for plant breeding are discussed.
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Affiliation(s)
- Christina Cowger
- USDA-ARS and North Carolina State University, Raleigh, North Carolina 27695, USA;
| | - James K M Brown
- Department of Crop Genetics, John Innes Centre, Colney, Norwich NR4 7UK, United Kingdom;
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Boixel AL, Delestre G, Legeay J, Chelle M, Suffert F. Phenotyping Thermal Responses of Yeasts and Yeast-like Microorganisms at the Individual and Population Levels: Proof-of-Concept, Development and Application of an Experimental Framework to a Plant Pathogen. MICROBIAL ECOLOGY 2019; 78:42-56. [PMID: 30280234 DOI: 10.1007/s00248-018-1253-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Accepted: 08/29/2018] [Indexed: 06/08/2023]
Abstract
Deciphering the responses of microbial populations to spatiotemporal changes in their thermal environment is instrumental in improving our understanding of their eco-evolutionary dynamics. Recent studies have shown that current phenotyping protocols do not adequately address all dimensions of phenotype expression. Therefore, these methods can give biased assessments of sensitivity to temperature, leading to misunderstandings concerning the ecological processes underlying thermal plasticity. We describe here a new robust and versatile experimental framework for the accurate investigation of thermal performance and phenotypic diversity in yeasts and yeast-like microorganisms, at the individual and population levels. In addition to proof-of-concept, the application of this framework to the fungal wheat pathogen Zymoseptoria tritici resulted in detailed characterisations for this yeast-like microorganism of (i) the patterns of temperature-dependent changes in performance for four fitness traits; (ii) the consistency in thermal sensitivity rankings of strains between in planta and in vitro growth assessments; (iii) significant interindividual variation in thermal responses, with four principal thermotypes detected in a sample of 66 strains; and (iv) the ecological consequences of this diversity for population-level processes through pairwise competition experiments highlighting temperature-dependent outcomes. These findings extend our knowledge and ability to quantify and categorise the phenotypic heterogeneity of thermal responses. As such, they lay the foundations for further studies elucidating local adaptation patterns and the effects of temperature variations on eco-evolutionary and epidemiological processes.
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Affiliation(s)
- Anne-Lise Boixel
- UMR BIOGER, INRA, AgroParisTech, Université Paris-Saclay, 78850, Thiverval-Grignon, France.
| | - Ghislain Delestre
- UMR BIOGER, INRA, AgroParisTech, Université Paris-Saclay, 78850, Thiverval-Grignon, France
| | - Jean Legeay
- UMR BIOGER, INRA, AgroParisTech, Université Paris-Saclay, 78850, Thiverval-Grignon, France
| | - Michaël Chelle
- UMR ECOSYS, INRA, AgroParisTech, Université Paris-Saclay, 78850, Thiverval-Grignon, France
| | - Frédéric Suffert
- UMR BIOGER, INRA, AgroParisTech, Université Paris-Saclay, 78850, Thiverval-Grignon, France.
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Vieira A, Silva DN, Várzea V, Paulo OS, Batista D. Genome-Wide Signatures of Selection in Colletotrichum kahawae Reveal Candidate Genes Potentially Involved in Pathogenicity and Aggressiveness. Front Microbiol 2019; 10:1374. [PMID: 31275287 PMCID: PMC6593080 DOI: 10.3389/fmicb.2019.01374] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Accepted: 06/03/2019] [Indexed: 12/26/2022] Open
Abstract
Plants and their pathogens are engaged in continuous evolutionary battles, with pathogens evolving to circumvent plant defense mechanisms and plants responding through enhanced protection to prevent or mitigate damage induced by pathogen attack. Managed ecosystems are composed of genetically identical populations of crop plants with few changes from year to year. These environments are highly conducive to the emergence and dissemination of pathogens and they exert selective pressure for both qualitative virulence factors responsible for fungal pathogenicity, and quantitative traits linked to pathogen fitness, such as aggressiveness. In this study, we used a comparative genome-wide approach to investigate the genomic basis underlying the pathogenicity and aggressiveness of the fungal coffee pathogen Colletotrichum kahawae infecting green coffee berries. The pathogenicity was investigated by comparing genomic variation between C. kahawae and its non-pathogenic sibling species, while the aggressiveness was studied by a genome-wide association approach with groups of isolates with different phenotypic profiles. High genetic differentiation was observed between C. kahawae and the most closely related species with 5,560 diagnostic SNPs identified, in which a significant enrichment of non-synonymous mutations was detected. Functional annotation of these non-synonymous mutations revealed a significant enrichment mainly in two gene ontology categories, “oxidation–reduction process” and “integral component of membrane.” Finally, the annotation of several genes potentially under-selection revealed that C. kahawae’s pathogenicity may be a complex biological process, in which important biological functions, such as, detoxification and transport, regulation of host and pathogen gene expression, and signaling are involved. On the other hand, the genome-wide association analyses for aggressiveness were able to identify 10 SNPs and 15 SNPs of small effect in single and multi-association analysis, respectively, from which 7 were common, giving in total 18 SNPs potentially associated. The annotation of these genomic regions allowed the identification of four candidate genes encoding F-box domain-containing, nitrosoguanidine resistance, Fungal specific transcription factor domain-containing and C6 transcription factor that could be associated with aggressiveness. This study shed light, for the first time, on the genetic mechanisms of C. kahawae host specialization.
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Affiliation(s)
- Ana Vieira
- Centro de Investigação das Ferrugens do Cafeeiro, Instituto Superior de Agronomia, Universidade de Lisboa, Oeiras, Portugal.,Computational Biology and Population Genomics Group, Centre for Ecology, Evolution and Environmental Changes, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal.,Linking Landscape, Environment, Agriculture and Food, Instituto Superior de Agronomia, Universidade de Lisboa, Lisbon, Portugal
| | - Diogo Nuno Silva
- Centro de Investigação das Ferrugens do Cafeeiro, Instituto Superior de Agronomia, Universidade de Lisboa, Oeiras, Portugal.,Computational Biology and Population Genomics Group, Centre for Ecology, Evolution and Environmental Changes, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal.,Linking Landscape, Environment, Agriculture and Food, Instituto Superior de Agronomia, Universidade de Lisboa, Lisbon, Portugal
| | - Vitor Várzea
- Centro de Investigação das Ferrugens do Cafeeiro, Instituto Superior de Agronomia, Universidade de Lisboa, Oeiras, Portugal.,Linking Landscape, Environment, Agriculture and Food, Instituto Superior de Agronomia, Universidade de Lisboa, Lisbon, Portugal
| | - Octávio Salgueiro Paulo
- Computational Biology and Population Genomics Group, Centre for Ecology, Evolution and Environmental Changes, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal
| | - Dora Batista
- Centro de Investigação das Ferrugens do Cafeeiro, Instituto Superior de Agronomia, Universidade de Lisboa, Oeiras, Portugal.,Computational Biology and Population Genomics Group, Centre for Ecology, Evolution and Environmental Changes, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal.,Linking Landscape, Environment, Agriculture and Food, Instituto Superior de Agronomia, Universidade de Lisboa, Lisbon, Portugal
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Pearce TL, Scott JB, Pilkington SJ, Pethybridge SJ, Hay FS. Evidence for Sexual Recombination in Didymella tanaceti Populations, and Their Evolution Over Spring Production in Australian Pyrethrum Fields. PHYTOPATHOLOGY 2019; 109:155-168. [PMID: 29989847 DOI: 10.1094/phyto-08-17-0280-r] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Tan spot, caused by Didymella tanaceti, is one of the most important foliar diseases affecting pyrethrum in Tasmania, Australia. Population dynamics, including mating-type ratios and genetic diversity of D. tanaceti, was characterized within four geographically separated fields in both late winter and spring 2012. A set of 10 microsatellite markers was developed and used to genotype 774 D. tanaceti isolates. Isolates were genotypically diverse, with 123 multilocus genotypes (MLG) identified across the four fields. Fifty-eight MLG contained single isolates and Psex analysis estimated that, within many of the recurrent MLG, there were multiple clonal lineages derived from recombination. Isolates of both mating types were at a 1:1 ratio following clone correction in each field at each sampling period, which was suggestive of sexual recombination. No evidence of genetic divergence of isolates of each mating type was identified, indicating admixture within the population. Linkage equilibrium in two of the four field populations sampled in late winter could not be discounted following clone correction. Evaluation of temporal changes in gene and genotypic diversity identified that they were both similar for the two sampling periods despite an increased D. tanaceti isolation frequency in spring. Genetic differentiation was similar in populations sampled between the two sampling periods within fields or between fields. These results indicated that sexual reproduction may have contributed to tan spot epidemics within Australian pyrethrum fields and has contributed to a genetically diverse D. tanaceti population.
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Affiliation(s)
- Tamieka L Pearce
- First, second, and third authors, Tasmanian Institute of Agriculture, University of Tasmania, Burnie, Tasmania 7320, Australia; fourth and fifth authors, Plant Pathology & Plant-Microbe Biology Section, School of Integrative Plant Science, Cornell AgriTech at the New York State Agricultural Experiment Station, Cornell University, Geneva, NY 14456
| | - Jason B Scott
- First, second, and third authors, Tasmanian Institute of Agriculture, University of Tasmania, Burnie, Tasmania 7320, Australia; fourth and fifth authors, Plant Pathology & Plant-Microbe Biology Section, School of Integrative Plant Science, Cornell AgriTech at the New York State Agricultural Experiment Station, Cornell University, Geneva, NY 14456
| | - Stacey J Pilkington
- First, second, and third authors, Tasmanian Institute of Agriculture, University of Tasmania, Burnie, Tasmania 7320, Australia; fourth and fifth authors, Plant Pathology & Plant-Microbe Biology Section, School of Integrative Plant Science, Cornell AgriTech at the New York State Agricultural Experiment Station, Cornell University, Geneva, NY 14456
| | - Sarah J Pethybridge
- First, second, and third authors, Tasmanian Institute of Agriculture, University of Tasmania, Burnie, Tasmania 7320, Australia; fourth and fifth authors, Plant Pathology & Plant-Microbe Biology Section, School of Integrative Plant Science, Cornell AgriTech at the New York State Agricultural Experiment Station, Cornell University, Geneva, NY 14456
| | - Frank S Hay
- First, second, and third authors, Tasmanian Institute of Agriculture, University of Tasmania, Burnie, Tasmania 7320, Australia; fourth and fifth authors, Plant Pathology & Plant-Microbe Biology Section, School of Integrative Plant Science, Cornell AgriTech at the New York State Agricultural Experiment Station, Cornell University, Geneva, NY 14456
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Guijarro B, Larena I, Melgarejo P, De Cal A. Surfactant effects on wettability of Penicillium frequentans formulations to improve brown rot biocontrol. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2018; 98:5832-5840. [PMID: 29770458 DOI: 10.1002/jsfa.9133] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Revised: 05/11/2018] [Accepted: 05/14/2018] [Indexed: 06/08/2023]
Abstract
BACKGROUND Penicillium frequentans can be used in the management of brown rot caused by Monilinia spp. Competition is the primary mode of biocontrol activity of P. frequentans, which must therefore cover most of fruit surface to avoid pathogen infection. Our objective was to optimize the efficacy of P. frequentans by maximizing fruit surface coverage and retention with the antagonist formulation by surfactant incorporation. RESULTS Sixteen surfactants were assessed for the management of brown rot at 3-5 different concentrations. Nine surfactants increased the droplet surface up to 2.5 times compared with water on an inert surface, with or without the presence of P. frequentans in each drop. Eight surfactants increased P. frequentans on the fruit surface, enhancing colony forming units after run off or lateral spray application uptake by 50% compared to the control without surfactants. But only some doses of sodium carboxymethyl cellulose, gelatin, Tween 20, sorbitan alkyl esters, synthetic latex, polyethylene glycol isotridecyl ether, and hydroxypropyl methylcellulose could show the same covered fruit surface after run off or lateral spray application. There were also no phytotoxic side-effects on five different species of stone fruit. CONCLUSIONS The efficacy of P. frequentans dry conidia can be enhanced by optimizing the composition of the formulation with surfactants. © 2018 Society of Chemical Industry.
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Affiliation(s)
- Belén Guijarro
- Department of Plant Protection, Phytopathology Fungi Unit, National Institute for Agriculture and Food Research, INIA, Madrid, Spain
| | - Inmaculada Larena
- Department of Plant Protection, Phytopathology Fungi Unit, National Institute for Agriculture and Food Research, INIA, Madrid, Spain
| | - Paloma Melgarejo
- Department of Plant Protection, Phytopathology Fungi Unit, National Institute for Agriculture and Food Research, INIA, Madrid, Spain
| | - Antonieta De Cal
- Department of Plant Protection, Phytopathology Fungi Unit, National Institute for Agriculture and Food Research, INIA, Madrid, Spain
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