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A Genome-Wide Association study in Arabidopsis thaliana to decipher the adaptive genetics of quantitative disease resistance in a native heterogeneous environment. PLoS One 2022; 17:e0274561. [PMID: 36190949 PMCID: PMC9529085 DOI: 10.1371/journal.pone.0274561] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Accepted: 08/31/2022] [Indexed: 11/05/2022] Open
Abstract
Pathogens are often the main selective agents acting in plant communities, thereby influencing the distribution of polymorphism at loci affecting resistance within and among natural plant populations. In addition, the outcome of plant-pathogen interactions can be drastically affected by abiotic and biotic factors at different spatial and temporal grains. The characterization of the adaptive genetic architecture of disease resistance in native heterogeneous environments is however still missing. In this study, we conducted an in situ Genome-Wide Association study in the spatially heterogeneous native habitat of a highly genetically polymorphic local mapping population of Arabidopsis thaliana, to unravel the adaptive genetic architecture of quantitative disease resistance. Disease resistance largely differed among three native soils and was affected by the presence of the grass Poa annua. The observation of strong crossing reactions norms among the 195 A. thaliana genotypes for disease resistance among micro-habitats, combined with a negative fecundity-disease resistance relationship in each micro-habitat, suggest that alternative local genotypes of A. thaliana are favored under contrasting environmental conditions at the scale of few meters. A complex genetic architecture was detected for disease resistance and fecundity. However, only few QTLs were common between these two traits. Heterogeneous selection in this local population should therefore promote the maintenance of polymorphism at only few candidate resistance genes.
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Masini L, Grenville‐Briggs LJ, Andreasson E, Råberg L, Lankinen Å. Tolerance and overcompensation to infection by Phytophthora infestans in the wild perennial climber Solanum dulcamara. Ecol Evol 2019; 9:4557-4567. [PMID: 31031927 PMCID: PMC6476776 DOI: 10.1002/ece3.5057] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Revised: 02/16/2019] [Accepted: 02/21/2019] [Indexed: 12/12/2022] Open
Abstract
Studies of infection by Phytophthora infestans-the causal agent of potato late blight-in wild species can provide novel insights into plant defense responses, and indicate how wild plants might be influenced by recurrent epidemics in agricultural fields. In the present study, our aim was to investigate if different clones of Solanum dulcamara (a relative of potato) collected in the wild differ in resistance and tolerance to infection by a common European isolate of P. infestans. We performed infection experiments with six S. dulcamara genotypes (clones) both in the laboratory and in the field and measured the degree of infection and plant performance traits. In the laboratory, the six evaluated genotypes varied from resistant to susceptible, as measured by degree of infection 20 days post infection. Two of the four genotypes susceptible to infection showed a quadratic (concave downward) relationship between the degree of infection and shoot length, with maximum shoot length at intermediate values of infection. This result suggests overcompensation, that is, an increase in growth in infected individuals. The number of leaves decreased with increasing degree of infection, but at different rates in the four susceptible genotypes, indicating genetic variation for tolerance. In the field, the inoculated genotypes did not show any disease symptoms, but plant biomass at the end of the growing season was higher for inoculated plants than for controls, in-line with the overcompensation detected in the laboratory. We conclude that in S. dulcamara there are indications of genetic variation for both resistance and tolerance to P. infestans infection. Moreover, some genotypes displayed overcompensation. Learning about plant tolerance and overcompensation to infection by pathogens can help broaden our understanding of plant defense in natural populations and help develop more sustainable plant protection strategies for economically important crop diseases.
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Affiliation(s)
- Laura Masini
- Plant Protection BiologySwedish University of Agricultural SciencesAlnarpSweden
- Present address:
British American TobaccoPlant Biotechnology DivisionCambridgeUK
| | | | - Erik Andreasson
- Plant Protection BiologySwedish University of Agricultural SciencesAlnarpSweden
| | - Lars Råberg
- Department of BiologyLund UniversityLundSweden
| | - Åsa Lankinen
- Plant Protection BiologySwedish University of Agricultural SciencesAlnarpSweden
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Peltier E, Sharma V, Martí Raga M, Roncoroni M, Bernard M, Jiranek V, Gibon Y, Marullo P. Dissection of the molecular bases of genotype x environment interactions: a study of phenotypic plasticity of Saccharomyces cerevisiae in grape juices. BMC Genomics 2018; 19:772. [PMID: 30409183 PMCID: PMC6225642 DOI: 10.1186/s12864-018-5145-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Accepted: 10/05/2018] [Indexed: 11/17/2022] Open
Abstract
Background The ability of a genotype to produce different phenotypes according to its surrounding environment is known as phenotypic plasticity. Within different individuals of the same species, phenotypic plasticity can vary greatly. This contrasting response is caused by gene-by-environment interactions (GxE). Understanding GxE interactions is particularly important in agronomy, since selected breeds and varieties may have divergent phenotypes according to their growing environment. Industrial microbes such as Saccharomyces cerevisiae are also faced with a large range of fermentation conditions that affect their technological properties. Finding the molecular determinism of such variations is a critical task for better understanding the genetic bases of phenotypic plasticity and can also be helpful in order to improve breeding methods. Results In this study we implemented a QTL mapping program using two independent cross (~ 100 progeny) in order to investigate the molecular basis of yeast phenotypic response in a wine fermentation context. Thanks to whole genome sequencing approaches, both crosses were genotyped, providing saturated genetic maps of thousands of markers. Linkage analyses allowed the detection of 78 QTLs including 21 with significant interaction with the environmental conditions. Molecular dissection of a major QTL demonstrated that the sulfite pump Ssu1p has a pleiotropic effect and impacts the phenotypic plasticity of several traits. Conclusions The detection of QTLs and their interactions with environment emphasizes the complexity of yeast industrial traits. The validation of the interaction of SSU1 allelic variants with the nature of the fermented juice increases knowledge about the impact of the sulfite pump during fermentation. All together these results pave the way for exploiting and deciphering the genetic determinism of phenotypic plasticity. Electronic supplementary material The online version of this article (10.1186/s12864-018-5145-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Emilien Peltier
- Univ. Bordeaux, ISVV, Unité de recherche OEnologie EA 4577, USC 1366 INRA, Bordeaux INP, Villenave d'Ornon, France. .,Biolaffort, Bordeaux, France.
| | - Vikas Sharma
- Univ. Bordeaux, ISVV, Unité de recherche OEnologie EA 4577, USC 1366 INRA, Bordeaux INP, Villenave d'Ornon, France
| | - Maria Martí Raga
- Univ. Bordeaux, ISVV, Unité de recherche OEnologie EA 4577, USC 1366 INRA, Bordeaux INP, Villenave d'Ornon, France.,Departament de Bioquímica i Biotecnologia, Facultat d'Enologia de Tarragona, Tarragona, Spain
| | - Miguel Roncoroni
- Wine Science Programme, University of Auckland, Private Bag, Auckland, 92019, New Zealand
| | - Margaux Bernard
- Univ. Bordeaux, ISVV, Unité de recherche OEnologie EA 4577, USC 1366 INRA, Bordeaux INP, Villenave d'Ornon, France.,Biolaffort, Bordeaux, France
| | - Vladimir Jiranek
- Department of Wine and Food Science, University of Adelaide, Urrbrae, South Australia, 5064, Australia
| | - Yves Gibon
- INRA, University of Bordeaux, UMR 1332 Fruit Biology and Pathology, F-33883, Villenave d'Ornon, France
| | - Philippe Marullo
- Univ. Bordeaux, ISVV, Unité de recherche OEnologie EA 4577, USC 1366 INRA, Bordeaux INP, Villenave d'Ornon, France.,Biolaffort, Bordeaux, France
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4
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Baker RL, Leong WF, An N, Brock MT, Rubin MJ, Welch S, Weinig C. Bayesian estimation and use of high-throughput remote sensing indices for quantitative genetic analyses of leaf growth. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2018; 131:283-298. [PMID: 29058049 DOI: 10.1007/s00122-017-3001-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Accepted: 10/09/2017] [Indexed: 06/07/2023]
Abstract
We develop Bayesian function-valued trait models that mathematically isolate genetic mechanisms underlying leaf growth trajectories by factoring out genotype-specific differences in photosynthesis. Remote sensing data can be used instead of leaf-level physiological measurements. Characterizing the genetic basis of traits that vary during ontogeny and affect plant performance is a major goal in evolutionary biology and agronomy. Describing genetic programs that specifically regulate morphological traits can be complicated by genotypic differences in physiological traits. We describe the growth trajectories of leaves using novel Bayesian function-valued trait (FVT) modeling approaches in Brassica rapa recombinant inbred lines raised in heterogeneous field settings. While frequentist approaches estimate parameter values by treating each experimental replicate discretely, Bayesian models can utilize information in the global dataset, potentially leading to more robust trait estimation. We illustrate this principle by estimating growth asymptotes in the face of missing data and comparing heritabilities of growth trajectory parameters estimated by Bayesian and frequentist approaches. Using pseudo-Bayes factors, we compare the performance of an initial Bayesian logistic growth model and a model that incorporates carbon assimilation (A max) as a cofactor, thus statistically accounting for genotypic differences in carbon resources. We further evaluate two remotely sensed spectroradiometric indices, photochemical reflectance (pri2) and MERIS Terrestrial Chlorophyll Index (mtci) as covariates in lieu of A max, because these two indices were genetically correlated with A max across years and treatments yet allow much higher throughput compared to direct leaf-level gas-exchange measurements. For leaf lengths in uncrowded settings, including A max improves model fit over the initial model. The mtci and pri2 indices also outperform direct A max measurements. Of particular importance for evolutionary biologists and plant breeders, hierarchical Bayesian models estimating FVT parameters improve heritabilities compared to frequentist approaches.
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Affiliation(s)
- Robert L Baker
- Department of Botany, University of Wyoming, Laramie, WY, 82071, USA.
- Biology Department, Miami University, Oxford, OH, 45056, USA.
| | - Wen Fung Leong
- Department of Agronomy, Kansas State University, Manhattan, KS, 66506, USA
| | - Nan An
- Department of Agronomy, Kansas State University, Manhattan, KS, 66506, USA
| | - Marcus T Brock
- Department of Botany, University of Wyoming, Laramie, WY, 82071, USA
| | - Matthew J Rubin
- Department of Botany, University of Wyoming, Laramie, WY, 82071, USA
| | - Stephen Welch
- Department of Agronomy, Kansas State University, Manhattan, KS, 66506, USA
| | - Cynthia Weinig
- Department of Botany, University of Wyoming, Laramie, WY, 82071, USA
- Department of Molecular Biology, University of Wyoming, Laramie, WY, 82071, USA
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5
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Choi K, Reinhard C, Serra H, Ziolkowski PA, Underwood CJ, Zhao X, Hardcastle TJ, Yelina NE, Griffin C, Jackson M, Mézard C, McVean G, Copenhaver GP, Henderson IR. Recombination Rate Heterogeneity within Arabidopsis Disease Resistance Genes. PLoS Genet 2016; 12:e1006179. [PMID: 27415776 PMCID: PMC4945094 DOI: 10.1371/journal.pgen.1006179] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Accepted: 06/15/2016] [Indexed: 12/31/2022] Open
Abstract
Meiotic crossover frequency varies extensively along chromosomes and is typically concentrated in hotspots. As recombination increases genetic diversity, hotspots are predicted to occur at immunity genes, where variation may be beneficial. A major component of plant immunity is recognition of pathogen Avirulence (Avr) effectors by resistance (R) genes that encode NBS-LRR domain proteins. Therefore, we sought to test whether NBS-LRR genes would overlap with meiotic crossover hotspots using experimental genetics in Arabidopsis thaliana. NBS-LRR genes tend to physically cluster in plant genomes; for example, in Arabidopsis most are located in large clusters on the south arms of chromosomes 1 and 5. We experimentally mapped 1,439 crossovers within these clusters and observed NBS-LRR gene associated hotspots, which were also detected as historical hotspots via analysis of linkage disequilibrium. However, we also observed NBS-LRR gene coldspots, which in some cases correlate with structural heterozygosity. To study recombination at the fine-scale we used high-throughput sequencing to analyze ~1,000 crossovers within the RESISTANCE TO ALBUGO CANDIDA1 (RAC1) R gene hotspot. This revealed elevated intragenic crossovers, overlapping nucleosome-occupied exons that encode the TIR, NBS and LRR domains. The highest RAC1 recombination frequency was promoter-proximal and overlapped CTT-repeat DNA sequence motifs, which have previously been associated with plant crossover hotspots. Additionally, we show a significant influence of natural genetic variation on NBS-LRR cluster recombination rates, using crosses between Arabidopsis ecotypes. In conclusion, we show that a subset of NBS-LRR genes are strong hotspots, whereas others are coldspots. This reveals a complex recombination landscape in Arabidopsis NBS-LRR genes, which we propose results from varying coevolutionary pressures exerted by host-pathogen relationships, and is influenced by structural heterozygosity.
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Affiliation(s)
- Kyuha Choi
- Department of Plant Sciences, Downing Street, University of Cambridge, Cambridge, United Kingdom
| | - Carsten Reinhard
- Department of Plant Sciences, Downing Street, University of Cambridge, Cambridge, United Kingdom
| | - Heïdi Serra
- Department of Plant Sciences, Downing Street, University of Cambridge, Cambridge, United Kingdom
| | - Piotr A. Ziolkowski
- Department of Plant Sciences, Downing Street, University of Cambridge, Cambridge, United Kingdom
- Department of Biotechnology, Adam Mickiewicz University, Poznan, Poland
| | - Charles J. Underwood
- Department of Plant Sciences, Downing Street, University of Cambridge, Cambridge, United Kingdom
- Watson School of Biological Sciences, Cold Spring Harbor Laboratory, Cold Spring Harbor, New York, United States of America
| | - Xiaohui Zhao
- Department of Plant Sciences, Downing Street, University of Cambridge, Cambridge, United Kingdom
| | - Thomas J. Hardcastle
- Department of Plant Sciences, Downing Street, University of Cambridge, Cambridge, United Kingdom
| | - Nataliya E. Yelina
- Department of Plant Sciences, Downing Street, University of Cambridge, Cambridge, United Kingdom
| | - Catherine Griffin
- Department of Plant Sciences, Downing Street, University of Cambridge, Cambridge, United Kingdom
| | - Matthew Jackson
- Department of Plant Sciences, Downing Street, University of Cambridge, Cambridge, United Kingdom
| | - Christine Mézard
- Institut Jean-Pierre Bourgin, INRA, AgroParisTech, CNRS, Université Paris-Saclay, RD10, Versailles, France
| | - Gil McVean
- The Wellcome Trust Centre for Human Genetics, University of Oxford, Oxford, United Kingdom
| | - Gregory P. Copenhaver
- Department of Biology and the Integrative Program for Biological and Genome Sciences, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
- Lineberger Comprehensive Cancer Center, University of North Carolina School of Medicine, Chapel Hill, North Carolina, United States of America
| | - Ian R. Henderson
- Department of Plant Sciences, Downing Street, University of Cambridge, Cambridge, United Kingdom
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6
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French E, Kim BS, Iyer-Pascuzzi AS. Mechanisms of quantitative disease resistance in plants. Semin Cell Dev Biol 2016; 56:201-208. [PMID: 27212254 DOI: 10.1016/j.semcdb.2016.05.015] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Revised: 05/14/2016] [Accepted: 05/18/2016] [Indexed: 11/29/2022]
Abstract
Quantitative disease resistance (QDR) causes the reduction, but not absence, of disease, and is a major type of disease resistance for many crop species. QDR results in a continuous distribution of disease scores across a segregating population, and is typically due to many genes with small effects. It may also be a source of durable resistance. The past decade has seen significant progress in cloning genes underlying QDR. In this review, we focus on these recently cloned genes and identify new themes of QDR emerging from these studies.
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Affiliation(s)
- Elizabeth French
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907, United States
| | - Bong-Suk Kim
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907, United States
| | - Anjali S Iyer-Pascuzzi
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN 47907, United States.
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7
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Roux F, Bergelson J. The Genetics Underlying Natural Variation in the Biotic Interactions of Arabidopsis thaliana: The Challenges of Linking Evolutionary Genetics and Community Ecology. Curr Top Dev Biol 2016; 119:111-56. [PMID: 27282025 DOI: 10.1016/bs.ctdb.2016.03.001] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
In the context of global change, predicting the responses of plant communities in an ever-changing biotic environment calls for a multipronged approach at the interface of evolutionary genetics and community ecology. However, our understanding of the genetic basis of natural variation involved in mediating biotic interactions, and associated adaptive dynamics of focal plants in their natural communities, is still in its infancy. Here, we review the genetic and molecular bases of natural variation in the response to biotic interactions (viruses, bacteria, fungi, oomycetes, herbivores, and plants) in the model plant Arabidopsis thaliana as well as the adaptive value of these bases. Among the 60 identified genes are a number that encode nucleotide-binding site leucine-rich repeat (NBS-LRR)-type proteins, consistent with early examples of plant defense genes. However, recent studies have revealed an extensive diversity in the molecular mechanisms of defense. Many types of genetic variants associate with phenotypic variation in biotic interactions, even among the genes of large effect that tend to be identified. In general, we found that (i) balancing selection rather than directional selection explains the observed patterns of genetic diversity within A. thaliana and (ii) the cost/benefit tradeoffs of adaptive alleles can be strongly dependent on both genomic and environmental contexts. Finally, because A. thaliana rarely interacts with only one biotic partner in nature, we highlight the benefit of exploring diffuse biotic interactions rather than tightly associated host-enemy pairs. This challenge would help to improve our understanding of coevolutionary quantitative genetics within the context of realistic community complexity.
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Affiliation(s)
- F Roux
- INRA, Laboratoire des Interactions Plantes-Microorganismes (LIPM), UMR441, Castanet-Tolosan, France; CNRS, Laboratoire des Interactions Plantes-Microorganismes (LIPM), UMR2594, Castanet-Tolosan, France.
| | - J Bergelson
- University of Chicago, Chicago, IL, United States
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8
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Baker RL, Leong WF, Brock MT, Markelz RJC, Covington MF, Devisetty UK, Edwards CE, Maloof J, Welch S, Weinig C. Modeling development and quantitative trait mapping reveal independent genetic modules for leaf size and shape. THE NEW PHYTOLOGIST 2015; 208:257-68. [PMID: 26083847 DOI: 10.1111/nph.13509] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2015] [Accepted: 05/11/2015] [Indexed: 05/24/2023]
Abstract
Improved predictions of fitness and yield may be obtained by characterizing the genetic controls and environmental dependencies of organismal ontogeny. Elucidating the shape of growth curves may reveal novel genetic controls that single-time-point (STP) analyses do not because, in theory, infinite numbers of growth curves can result in the same final measurement. We measured leaf lengths and widths in Brassica rapa recombinant inbred lines (RILs) throughout ontogeny. We modeled leaf growth and allometry as function valued traits (FVT), and examined genetic correlations between these traits and aspects of phenology, physiology, circadian rhythms and fitness. We used RNA-seq to construct a SNP linkage map and mapped trait quantitative trait loci (QTL). We found genetic trade-offs between leaf size and growth rate FVT and uncovered differences in genotypic and QTL correlations involving FVT vs STPs. We identified leaf shape (allometry) as a genetic module independent of length and width and identified selection on FVT parameters of development. Leaf shape is associated with venation features that affect desiccation resistance. The genetic independence of leaf shape from other leaf traits may therefore enable crop optimization in leaf shape without negative effects on traits such as size, growth rate, duration or gas exchange.
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Affiliation(s)
- Robert L Baker
- Department of Botany, University of Wyoming, Laramie, WY, 82071, USA
| | - Wen Fung Leong
- Department of Agronomy, Kansas State University, Manhattan, KS, 66506, USA
| | - Marcus T Brock
- Department of Botany, University of Wyoming, Laramie, WY, 82071, USA
| | - R J Cody Markelz
- Department of Plant Biology, University of California, Davis, CA, 95616, USA
| | - Michael F Covington
- Department of Plant Biology, University of California, Davis, CA, 95616, USA
| | - Upendra K Devisetty
- Department of Plant Biology, University of California, Davis, CA, 95616, USA
| | - Christine E Edwards
- Center for Conservation and Sustainable Development, Missouri Botanical Garden, St Louis, MO, 63166, USA
| | - Julin Maloof
- Department of Plant Biology, University of California, Davis, CA, 95616, USA
| | - Stephen Welch
- Department of Agronomy, Kansas State University, Manhattan, KS, 66506, USA
| | - Cynthia Weinig
- Department of Botany, University of Wyoming, Laramie, WY, 82071, USA
- Department of Molecular Biology, University of Wyoming, Laramie, WY, 82071, USA
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9
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Meaden S, Paszkiewicz K, Koskella B. The cost of phage resistance in a plant pathogenic bacterium is context-dependent. Evolution 2015; 69:1321-8. [PMID: 25809535 PMCID: PMC4979666 DOI: 10.1111/evo.12652] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Accepted: 03/17/2015] [Indexed: 12/24/2022]
Abstract
Parasites are ubiquitous features of living systems and many parasites severely reduce the fecundity or longevity of their hosts. This parasite-imposed selection on host populations should strongly favor the evolution of host resistance, but hosts typically face a trade-off between investment in reproductive fitness and investment in defense against parasites. The magnitude of such a trade-off is likely to be context-dependent, and accordingly costs that are key in shaping evolution in nature may not be easily observable in an artificial environment. We set out to assess the costs of phage resistance for a plant pathogenic bacterium in its natural plant host versus in a nutrient-rich, artificial medium. We demonstrate that mutants of Pseudomonas syringae that have evolved resistance via a single mutational step pay a substantial cost for this resistance when grown on their tomato plant hosts, but do not realize any measurable growth rate costs in nutrient-rich media. This work demonstrates that resistance to phage can significantly alter bacterial growth within plant hosts, and therefore that phage-mediated selection in nature is likely to be an important component of bacterial pathogenicity.
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Affiliation(s)
- Sean Meaden
- College of Life and Environmental Sciences, University of Exeter, Penryn Campus, TR10 9FE, United Kingdom.
| | - Konrad Paszkiewicz
- College of Life and Environmental Sciences, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter, EX4 4QD, United Kingdom
| | - Britt Koskella
- College of Life and Environmental Sciences, University of Exeter, Penryn Campus, TR10 9FE, United Kingdom
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10
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Neve P, Busi R, Renton M, Vila-Aiub MM. Expanding the eco-evolutionary context of herbicide resistance research. PEST MANAGEMENT SCIENCE 2014; 70:1385-93. [PMID: 24723489 DOI: 10.1002/ps.3757] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2013] [Revised: 01/29/2014] [Accepted: 01/29/2014] [Indexed: 05/26/2023]
Abstract
The potential for human-driven evolution in economically and environmentally important organisms in medicine, agriculture and conservation management is now widely recognised. The evolution of herbicide resistance in weeds is a classic example of rapid adaptation in the face of human-mediated selection. Management strategies that aim to slow or prevent the evolution of herbicide resistance must be informed by an understanding of the ecological and evolutionary factors that drive selection in weed populations. Here, we argue for a greater focus on the ultimate causes of selection for resistance in herbicide resistance studies. The emerging fields of eco-evolutionary dynamics and applied evolutionary biology offer a means to achieve this goal and to consider herbicide resistance in a broader and sometimes novel context. Four relevant research questions are presented, which examine (i) the impact of herbicide dose on selection for resistance, (ii) plant fitness in herbicide resistance studies, (iii) the efficacy of herbicide rotations and mixtures and (iv) the impacts of gene flow on resistance evolution and spread. In all cases, fundamental ecology and evolution have the potential to offer new insights into herbicide resistance evolution and management.
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Affiliation(s)
- Paul Neve
- School of Life Sciences, University of Warwick, Coventry, UK
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11
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Berger DK, Carstens M, Korsman JN, Middleton F, Kloppers FJ, Tongoona P, Myburg AA. Mapping QTL conferring resistance in maize to gray leaf spot disease caused by Cercospora zeina. BMC Genet 2014; 15:60. [PMID: 24885661 PMCID: PMC4059882 DOI: 10.1186/1471-2156-15-60] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Accepted: 05/15/2014] [Indexed: 11/21/2022] Open
Abstract
BACKGROUND Gray leaf spot (GLS) is a globally important foliar disease of maize. Cercospora zeina, one of the two fungal species that cause the disease, is prevalent in southern Africa, China, Brazil and the eastern corn belt of the USA. Identification of QTL for GLS resistance in subtropical germplasm is important to support breeding programmes in developing countries where C. zeina limits production of this staple food crop. RESULTS A maize RIL population (F7:S6) from a cross between CML444 and SC Malawi was field-tested under GLS disease pressure at five field sites over three seasons in KwaZulu-Natal, South Africa. Thirty QTL identified from eleven field trials (environments) were consolidated to seven QTL for GLS resistance based on their expression in at least two environments and location in the same core maize bins. Four GLS resistance alleles were derived from the more resistant parent CML444 (bin 1.10, 4.08, 9.04/9.05, 10.06/10.07), whereas the remainder were from SC Malawi (bin 6.06/6.07, 7.02/7.03, 9.06). QTLs in bin 4.08 and bin 6.06/6.07 were also detected as joint QTLs, each explained more than 11% of the phenotypic variation, and were identified in four and seven environments, respectively. Common markers were used to allocate GLS QTL from eleven previous studies to bins on the IBM2005 map, and GLS QTL "hotspots" were noted. Bin 4.08 and 7.02/7.03 GLS QTL from this study overlapped with hotspots, whereas the bin 6.06/6.07 and bin 9.06 QTLs appeared to be unique. QTL for flowering time (bin 1.07, 4.09) in this population did not correspond to QTL for GLS resistance. CONCLUSIONS QTL mapping of a RIL population from the subtropical maize parents CML444 and SC Malawi identified seven QTL for resistance to gray leaf spot disease caused by C. zeina. These QTL together with QTL from eleven studies were allocated to bins on the IBM2005 map to provide a basis for comparison. Hotspots of GLS QTL were identified on chromosomes one, two, four, five and seven, with QTL in the current study overlapping with two of these. Two QTL from this study did not overlap with previously reported QTL.
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Affiliation(s)
- Dave K Berger
- Department of Plant Science, Forestry and Agricultural Biotechnology Institute (FABI), Plant Sciences Complex, University of Pretoria, Private Bag X20, Hatfield 0028, South Africa
| | - Maryke Carstens
- Department of Plant Science, Forestry and Agricultural Biotechnology Institute (FABI), Plant Sciences Complex, University of Pretoria, Private Bag X20, Hatfield 0028, South Africa
| | - Jeanne N Korsman
- Department of Plant Science, Forestry and Agricultural Biotechnology Institute (FABI), Plant Sciences Complex, University of Pretoria, Private Bag X20, Hatfield 0028, South Africa
| | | | | | - Pangirayi Tongoona
- African Centre for Crop Improvement, University of KwaZulu-Natal, Pietermaritzburg, South Africa
| | - Alexander A Myburg
- Department of Genetics, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria, South Africa
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12
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Huet G. Breeding for resistances to Ralstonia solanacearum. FRONTIERS IN PLANT SCIENCE 2014; 5:715. [PMID: 25566289 PMCID: PMC4264415 DOI: 10.3389/fpls.2014.00715] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/22/2014] [Accepted: 11/27/2014] [Indexed: 05/20/2023]
Abstract
Ralstonia solanacearum is one of the most devastating bacterial plant pathogens due to its large host range, worldwide geographic distribution and persistence in fields. This soilborne pathogen is the causal agent of bacterial wilt and it can infect major agricultural crops thereby reducing significantly their yield. To favor infection, the bacterium delivers, through the type three secretion system, effectors that manipulate plant immunity. In this review, the relative efficiency of control strategies and existing resistances to R. solanacearum will be presented. Then, the genetic and molecular insights gained from the study of bacterial wilt in model plants will be described. Finally, I will explore how the knowledge gathered from unraveling avirulence and virulence mechanisms of R. solanacearum effectors could help to develop more durable resistances in crop plants toward this destructive pathogen.
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Affiliation(s)
- Gaëlle Huet
- INRA, Laboratoire des Interactions Plantes-Microorganismes, UMR441, Castanet-TolosanFrance
- CNRS, Laboratoire des Interactions Plantes-Microorganismes, UMR2594, Castanet-TolosanFrance
- *Correspondence: Gaëlle Huet, Laboratoire des Interactions Plantes Microorganismes, 24 chemin de Borde Rouge - Auzeville, CS 52627, 31326 Castanet-Tolosan, France e-mail:
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Brachi B, Villoutreix R, Faure N, Hautekèete N, Piquot Y, Pauwels M, Roby D, Cuguen J, Bergelson J, Roux F. Investigation of the geographical scale of adaptive phenological variation and its underlying genetics in Arabidopsis thaliana. Mol Ecol 2013; 22:4222-4240. [DOI: 10.1111/mec.12396] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2012] [Revised: 05/21/2013] [Accepted: 05/23/2013] [Indexed: 02/02/2023]
Affiliation(s)
- Benjamin Brachi
- Laboratoire Génétique et Evolution des Populations Végétales; UMR CNRS 8198; Université des Sciences et Technologies de Lille - Lille 1; F-59655 Villeneuve d'Ascq Cedex France
- Department of Ecology and Evolution; University of Chicago; Chicago IL 60637 USA
| | - Romain Villoutreix
- Laboratoire Génétique et Evolution des Populations Végétales; UMR CNRS 8198; Université des Sciences et Technologies de Lille - Lille 1; F-59655 Villeneuve d'Ascq Cedex France
| | - Nathalie Faure
- Laboratoire Génétique et Evolution des Populations Végétales; UMR CNRS 8198; Université des Sciences et Technologies de Lille - Lille 1; F-59655 Villeneuve d'Ascq Cedex France
| | - Nina Hautekèete
- Laboratoire Génétique et Evolution des Populations Végétales; UMR CNRS 8198; Université des Sciences et Technologies de Lille - Lille 1; F-59655 Villeneuve d'Ascq Cedex France
| | - Yves Piquot
- Laboratoire Génétique et Evolution des Populations Végétales; UMR CNRS 8198; Université des Sciences et Technologies de Lille - Lille 1; F-59655 Villeneuve d'Ascq Cedex France
| | - Maxime Pauwels
- Laboratoire Génétique et Evolution des Populations Végétales; UMR CNRS 8198; Université des Sciences et Technologies de Lille - Lille 1; F-59655 Villeneuve d'Ascq Cedex France
| | - Dominique Roby
- INRA; Laboratoire des Interactions Plantes-Microorganismes (LIPM); UMR441; F-31326 Castanet-Tolosan France
- CNRS; Laboratoire des Interactions Plantes-Microorganismes (LIPM); UMR2594; F-31326 Castanet-Tolosan France
| | - Joël Cuguen
- Laboratoire Génétique et Evolution des Populations Végétales; UMR CNRS 8198; Université des Sciences et Technologies de Lille - Lille 1; F-59655 Villeneuve d'Ascq Cedex France
| | - Joy Bergelson
- Department of Ecology and Evolution; University of Chicago; Chicago IL 60637 USA
| | - Fabrice Roux
- Laboratoire Génétique et Evolution des Populations Végétales; UMR CNRS 8198; Université des Sciences et Technologies de Lille - Lille 1; F-59655 Villeneuve d'Ascq Cedex France
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14
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Van der Linden L, Bredenkamp J, Naidoo S, Fouché-Weich J, Denby KJ, Genin S, Marco Y, Berger DK. Gene-for-gene tolerance to bacterial wilt in Arabidopsis. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2013; 26:398-406. [PMID: 23234403 DOI: 10.1094/mpmi-07-12-0188-r] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Bacterial wilt caused by Ralstonia solanacearum is a disease of widespread economic importance that affects numerous plant species, including Arabidopsis thaliana. We describe a pathosystem between A. thaliana and biovar 3 phylotype I strain BCCF402 of R. solanacearum isolated from Eucalyptus trees. A. thaliana accession Be-0 was susceptible and accession Kil-0 was tolerant. Kil-0 exhibited no wilting symptoms and no significant reduction in fitness (biomass, seed yield, and germination efficiency) after inoculation with R. solanacearum BCCF402, despite high bacterial numbers in planta. This was in contrast to the well-characterized resistance response in the accession Nd-1, which limits bacterial multiplication at early stages of infection and does not wilt. R. solanacearum BCCF402 was highly virulent because the susceptible accession Be-0 was completely wilted after inoculation. Genetic analyses, allelism studies with Nd-1, and RRS1 cleaved amplified polymorphic sequence marker analysis showed that the tolerance phenotype in Kil-0 was dependent upon the resistance gene RRS1. Knockout and complementation studies of the R. solanacearum BCCF402 effector PopP2 confirmed that the tolerance response in Kil-0 was dependent upon the RRS1-PopP2 interaction. Our data indicate that the gene-for-gene interaction between RRS1 and PopP2 can contribute to tolerance, as well as resistance, which makes it a useful model system for evolutionary studies of the arms race between plants and bacterial pathogens. In addition, the results alert biotechnologists to the risk that deployment of RRS1 in transgenic crops may result in persistence of the pathogen in the field.
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Affiliation(s)
- Liesl Van der Linden
- Department of Plant Science, Forestry and Agricultural Research Institute, South Africa
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15
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Stinchcombe JR, Kirkpatrick M. Genetics and evolution of function-valued traits: understanding environmentally responsive phenotypes. Trends Ecol Evol 2012; 27:637-47. [PMID: 22898151 DOI: 10.1016/j.tree.2012.07.002] [Citation(s) in RCA: 131] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2012] [Revised: 06/28/2012] [Accepted: 07/05/2012] [Indexed: 10/28/2022]
Abstract
Many central questions in ecology and evolutionary biology require characterizing phenotypes that change with time and environmental conditions. Such traits are inherently functions, and new 'function-valued' methods use the order, spacing, and functional nature of the data typically ignored by traditional univariate and multivariate analyses. These rapidly developing methods account for the continuous change in traits of interest in response to other variables, and are superior to traditional summary-based analyses for growth trajectories, morphological shapes, and environmentally sensitive phenotypes. Here, we explain how function-valued methods make flexible use of data and lead to new biological insights. These approaches frequently offer enhanced statistical power, a natural basis of interpretation, and are applicable to many existing data sets. We also illustrate applications of function-valued methods to address ecological, evolutionary, and behavioral hypotheses, and highlight future directions.
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Affiliation(s)
- John R Stinchcombe
- Department of Ecology and Evolutionary Biology, University of Toronto, Toronto, ON, M5S3B2, Canada.
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Adaptive value of phenological traits in stressful environments: predictions based on seed production and laboratory natural selection. PLoS One 2012; 7:e32069. [PMID: 22403624 PMCID: PMC3293886 DOI: 10.1371/journal.pone.0032069] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2011] [Accepted: 01/19/2012] [Indexed: 11/19/2022] Open
Abstract
Phenological traits often show variation within and among natural populations of annual plants. Nevertheless, the adaptive value of post-anthesis traits is seldom tested. In this study, we estimated the adaptive values of pre- and post-anthesis traits in two stressful environments (water stress and interspecific competition), using the selfing annual species Arabidopsis thaliana. By estimating seed production and by performing laboratory natural selection (LNS), we assessed the strength and nature (directional, disruptive and stabilizing) of selection acting on phenological traits in A. thaliana under the two tested stress conditions, each with four intensities. Both the type of stress and its intensity affected the strength and nature of selection, as did genetic constraints among phenological traits. Under water stress, both experimental approaches demonstrated directional selection for a shorter life cycle, although bolting time imposes a genetic constraint on the length of the interval between bolting and anthesis. Under interspecific competition, results from the two experimental approaches showed discrepancies. Estimation of seed production predicted directional selection toward early pre-anthesis traits and long post-anthesis periods. In contrast, the LNS approach suggested neutrality for all phenological traits. This study opens questions on adaptation in complex natural environment where many selective pressures act simultaneously.
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Alcázar R, Parker JE. The impact of temperature on balancing immune responsiveness and growth in Arabidopsis. TRENDS IN PLANT SCIENCE 2011; 16:666-75. [PMID: 21963982 DOI: 10.1016/j.tplants.2011.09.001] [Citation(s) in RCA: 85] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2011] [Revised: 08/28/2011] [Accepted: 09/05/2011] [Indexed: 05/21/2023]
Abstract
Plants have evolved polymorphic immune receptors to recognize pathogens causing disease. However, triggering of resistance needs to be tuned to the local environment to maintain a balance between defense and growth. We consider here the impact of temperature as a key environmental factor influencing immune pathway activation in Arabidopsis. Genetic compensatory and molecular buffering mechanisms affecting the diversification, functionality and subcellular dynamics of immune receptors, reveal multiple points at which temperature intersects with host resistance signaling systems, including a role of at least one receptor in sensing temperature change. Analysis of temperature-dependent autoimmunity caused by allelic mismatches in hybrids of evolutionary diverged Arabidopsis accessions is illuminating processes by which plants maintain 'poise' between immune responsiveness and fitness in natural populations.
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Affiliation(s)
- Rubén Alcázar
- Department of Plant Breeding and Genetics, Max Planck Institute for Plant Breeding Research, Carl-von-Linne Weg 10, 50829 Cologne, Germany.
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18
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Hancock AM, Brachi B, Faure N, Horton MW, Jarymowycz LB, Sperone FG, Toomajian C, Roux F, Bergelson J. Adaptation to climate across the Arabidopsis thaliana genome. Science 2011; 334:83-6. [PMID: 21980108 DOI: 10.1126/science.1209244] [Citation(s) in RCA: 435] [Impact Index Per Article: 33.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Understanding the genetic bases and modes of adaptation to current climatic conditions is essential to accurately predict responses to future environmental change. We conducted a genome-wide scan to identify climate-adaptive genetic loci and pathways in the plant Arabidopsis thaliana. Amino acid-changing variants were significantly enriched among the loci strongly correlated with climate, suggesting that our scan effectively detects adaptive alleles. Moreover, from our results, we successfully predicted relative fitness among a set of geographically diverse A. thaliana accessions when grown together in a common environment. Our results provide a set of candidates for dissecting the molecular bases of climate adaptations, as well as insights about the prevalence of selective sweeps, which has implications for predicting the rate of adaptation.
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Affiliation(s)
- Angela M Hancock
- Department of Ecology and Evolution, University of Chicago, 1101 East 57th Street, Chicago, IL 60637, USA
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19
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Barrett LG, Bell T, Dwyer G, Bergelson J. Cheating, trade-offs and the evolution of aggressiveness in a natural pathogen population. Ecol Lett 2011; 14:1149-57. [PMID: 21951910 DOI: 10.1111/j.1461-0248.2011.01687.x] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
The evolutionary dynamics of pathogens are critically important for disease outcomes, prevalence and emergence. In this study we investigate ecological conditions that may promote the long-term maintenance of virulence polymorphisms in pathogen populations. Recent theory predicts that evolution towards increased virulence can be reversed if less-aggressive social 'cheats' exploit more aggressive 'cooperator' pathogens. However, there is no evidence that social exploitation operates within natural pathogen populations. We show that for the bacterium Pseudomonas syringae, major polymorphisms for pathogenicity are maintained at unexpectedly high frequencies in populations infecting the host Arabidopsis thaliana. Experiments reveal that less-aggressive strains substantially increase their growth potential in mixed infections and have a fitness advantage in non-host environments. These results suggest that niche differentiation can contribute to the maintenance of virulence polymorphisms, and that both within-host and between-host growth rates modulate cheating and cooperation in P. syringae populations.
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Affiliation(s)
- Luke G Barrett
- Department of Ecology & Evolution, University of Chicago, Chicago, IL, USA
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20
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Brown JKM, Tellier A. Plant-parasite coevolution: bridging the gap between genetics and ecology. ANNUAL REVIEW OF PHYTOPATHOLOGY 2011; 49:345-67. [PMID: 21513455 DOI: 10.1146/annurev-phyto-072910-095301] [Citation(s) in RCA: 157] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
We review current ideas about coevolution of plants and parasites, particularly processes that generate genetic diversity. Frequencies of host resistance and parasite virulence alleles that interact in gene-for-gene (GFG) relationships coevolve in the familiar boom-and-bust cycle, in which resistance is selected when virulence is rare, and virulence is selected when resistance is common. The cycle can result in stable polymorphism when diverse ecological and epidemiological factors cause negative direct frequency-dependent selection (ndFDS) on host resistance, parasite virulence, or both, such that the benefit of a trait to fitness declines as its frequency increases. Polymorphism can also be stabilized by overdominance, when heterozygous hosts have greater resistance than homozygotes to diverse pathogens. Genetic diversity can also persist in the form of statistical polymorphism, sustained by random processes acting on gene frequencies and population size. Stable polymorphism allows alleles to be long-lived and genetic variation to be detectable in natural populations. In agriculture, many of the factors promoting stability in host-parasite interactions have been lost, leading to arms races of host defenses and parasite effectors.
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Affiliation(s)
- James K M Brown
- Department of Disease and Stress Biology, John Innes Center, Colney, Norwich, NR4 7UH, United Kingdom.
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21
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Bergelson J, Roux F. Towards identifying genes underlying ecologically relevant traits in Arabidopsis thaliana. Nat Rev Genet 2010; 11:867-79. [PMID: 21085205 DOI: 10.1038/nrg2896] [Citation(s) in RCA: 210] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
A major challenge in evolutionary biology and plant breeding is to identify the genetic basis of complex quantitative traits, including those that contribute to adaptive variation. Here we review the development of new methods and resources to fine-map intraspecific genetic variation that underlies natural phenotypic variation in plants. In particular, the analysis of 107 quantitative traits reported in the first genome-wide association mapping study in Arabidopsis thaliana sets the stage for an exciting time in our understanding of plant adaptation. We also argue for the need to place phenotype-genotype association studies in an ecological context if one is to predict the evolutionary trajectories of plant species.
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Affiliation(s)
- Joy Bergelson
- Department of Ecology and Evolution, University of Chicago, Illinois 60637, USA.
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Kniskern JM, Barrett LG, Bergelson J. Maladaptation in wild populations of the generalist plant pathogen Pseudomonas syringae. Evolution 2010; 65:818-30. [PMID: 21044058 DOI: 10.1111/j.1558-5646.2010.01157.x] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Multihost pathogens occur widely on both natural and agriculturally managed hosts. Despite the importance of such generalists, evolutionary studies of host-pathogen interactions have largely focused on tightly coupled interactions between species pairs. We characterized resistance in a collection of Arabidopsis thaliana hosts, including 24 accessions collected from the Midwest USA and 24 from around the world, and patterns of virulence in a collection of Pseudomonas syringae strains, including 24 strains collected from wild Midwest populations of A. thaliana (residents) and 18 from an array of cultivated species (nonresidents). All of the nonresident strains and half of the resident strains elicited a resistance response on one or more A. thaliana accessions. The resident strains that failed to elicit any resistance response possessed an alternative type III secretion system (T3SS) that is unable to deliver effectors into plant host cells; as a result, these seemingly nonpathogenic strains are incapable of engaging in gene for gene interactions with A. thaliana. The remaining resident strains triggered greater resistance compared to nonresident strains, consistent with maladaptation of the resident bacterial population. We weigh the plausibility of two explanations: general maladaptation of pathogen strains and a more novel hypothesis whereby community level epidemiological dynamics result in adaptive dynamics favoring ephemeral hosts like A. thaliana.
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Affiliation(s)
- Joel M Kniskern
- Department of Ecology and Evolution, University of Chicago, 1101 E. 57th Street, Chicago, Illinois 60637, USA
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