DOCSLIB.ORG

Role of Host Genetic Diversity for Susceptibility-To-Infection in The

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Role of Host Genetic Diversity for Susceptibility-To-Infection in The bioRxiv preprint doi: https://doi.org/10.1101/602201; this version posted April 9, 2019. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY-NC-ND 4.0 International license. 1 Role of host genetic diversity for susceptibility-to-infection in 2 the evolution of virulence of a plant virus 3 4 Rubén González,1 Anamarija Butković,1 and Santiago F. Elena1,2,* 5 6 1Instituto de Biología Integrativa de Sistemas (I2SysBio), CSIC-Universitat de València, 7 46980 Paterna, València, Spain 8 2The Santa Fe Institute, Santa Fe, NM 87501, USA 9 *Corresponding author: E-mail: [email protected] 10 1 bioRxiv preprint doi: https://doi.org/10.1101/602201; this version posted April 9, 2019. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY-NC-ND 4.0 International license. 11 Abstract 12 Predicting viral emergence is difficult due to the stochastic nature of the underlying 13 processes and the many factors that govern pathogen evolution. Environmental factors 14 affecting the host, the pathogen and the interaction between both are key in emergence. 15 In particular, infectious disease dynamics are affected by spatiotemporal heterogeneity in 16 their environments. A broad knowledge of these factors will allow better estimating 17 where and when viral emergence is more likely to occur. Here we investigate how the 18 population structure for susceptibility-to-infection genes of the plant Arabidopsis 19 thaliana shapes the evolution of Turnip mosaic virus (TuMV). For doing so we have 20 evolved TuMV lineages in two radically different host population structures: (i) multiple 21 genetically homogeneous A. thaliana subpopulations and (ii) a single maximally 22 genetically heterogeneous population. We found faster adaptation of TuMV to 23 homogeneous than to heterogeneous host populations. However, viruses evolved in 24 heterogeneous host populations were more pathogenic and infectious than viruses 25 evolved in the homogeneous population. Furthermore, the viruses evolved in 26 homogeneous populations showed stronger signatures of local specialization than viruses 27 evolved in heterogeneous populations. These results illustrate how the genetic diversity 28 of hosts in an experimental ecosystem favors the evolution of virulence of a pathogen. 29 30 Key words: evolution of virulence, experimental evolution, infection matrix, host 31 population structure, Potyvirus, resistance to infection, virus evolution 32 2 bioRxiv preprint doi: https://doi.org/10.1101/602201; this version posted April 9, 2019. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY-NC-ND 4.0 International license. 33 1. Introduction 34 Since the term “emerging infectious disease” was coined in the mid-1900s, its definition 35 has evolved (Rosenthal et al. 2015). Woolhouse and Dye (2001) enunciated the most 36 comprehensive definition of an emerging infectious disease as one “whose incidence is 37 increasing following its first introduction into a new host population or whose incidence 38 is increasing in an existing host population as a result of long-term changes in its 39 underlying epidemiology”. Engering et al. (2013) rephrased this definition and suggested 40 that emergence events can be classified into three groups: (i) viruses showing up in a 41 novel host, (ii) mutant viral strains displaying novel traits in the same host, and (iii) 42 already known viral diseases spreading out in a new geographic area. Following these 43 definitions, viral emergence is usually associated to cross-species transmission but it can 44 actually occur with or without species jump (Di Giallonardo and Holmes 2015). 45 The emergence and re-emergence of viruses cause serious threatening to public 46 health (Morens and Fauci 2013) and are responsible for large yield losses in crops that 47 compromise food security (Vurro et al. 2010). Gaining knowledge on the principles that 48 govern viral emergence would allow to predict when and where such events are more 49 likely to happen. Achieving an accurate prediction of the emergence of viral diseases is 50 a challenging task, because emergence is governed by multiple and diverse factors that 51 remain poorly understood or completely unknown. Predictions will become even more 52 difficult under the ongoing climate change that will favor the conditions for development 53 and dispersal of the virus’ vectors (Garrett et al. 2006; Baylis 2017). 54 The spectrum of disease severity can be attributed to heterogeneity in virus virulence 55 or in host factors; the two are not necessarily independent explanations and they may 56 actually complement and/or interact each other. A problem faced by viruses is that host 57 populations consist of individuals that had different degrees of susceptibility to infection 3 bioRxiv preprint doi: https://doi.org/10.1101/602201; this version posted April 9, 2019. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY-NC-ND 4.0 International license. 58 (Schmid-Hempel and Koella 1994; Pfennig 2001). Therefore, adaptive changes 59 improving viral fitness in one host may be selected against, or be neutral, in an alternative 60 one. Genetic variability in susceptibility of hosts and infectiousness of viruses have been 61 well studied in animals and plants (Schmid-Hempel and Koella 1994; Altizer et al. 2006; 62 Brown and Tellier 2011; Anttila et al. 2015; Parrat et al. 2016). Variability within host 63 populations can arise from nonrandom spatial distributions of genotypes: social groups 64 of animals are more closely related to each other than to other members of the population, 65 and plant crops are generally cultivated as genetically homogeneous plots. These 66 situations facilitate virus transmission among genetically similar host genotypes. Spatial 67 structure and local migration predict evolution of less aggressive exploitation in 68 horizontally transmitted parasites (reviewed in Parrat et al. (2016)). For example, Boots 69 and Mealor (2007) observed that Plodia interpunctella granulosis virus (PiGV) evolved 70 in spatially-structured lepidopteran host populations become less virulent than the one 71 maintained in well mixed host populations. More recently, Berngruber et al. (2015) 72 showed that a latent l bacteriophage won competition against a virulent one in a spatially- 73 structured host populations but lost in well mixed populations. In a natural context, it has 74 been observed that virulent Linum marginale fungi were more frequent in highly resistant 75 Melampsora lini plant populations whereas avirulent pathogens dominated susceptible 76 populations (Thrall and Burdon 2003; Thrall et al. 2012). Similar results were observed 77 in laboratory evolution experiments with the pathosystem Arabidopsis thaliana - Tobacco 78 etch virus (TEV): a negative association between plant natural accessions permissiveness 79 to infection and TEV virulence was evolved (Hillung et al. 2014). Finally, host 80 population structure also promotes coexistence of hosts and parasites by creating refugia 81 due to limited dispersal of viruses; increased dispersal makes coexistence less stable 82 (Brockhurst et al. 2006). 4 bioRxiv preprint doi: https://doi.org/10.1101/602201; this version posted April 9, 2019. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY-NC-ND 4.0 International license. 83 The role of host population heterogeneity has also received quite a lot of attention 84 from theoreticians (e.g., Comins et al. 1992; Gandon et al. 1996; Boots and Sasaki 1999, 85 2002; Gandon and Michalakis 2002; Tellier and Brown 2011), resulting in a number of 86 interesting predictions that in many instances have not been properly tested 87 experimentally. One of the most tantalizing predictions is that in the absence of host 88 heterogeneity, parasites must evolve toward a host exploitation strategy that maximizes 89 transmission with low virulence (Haraguchi and Sasaki 2000; Regoes et al. 2000; 90 Rodríguez and Torres-Sorando 2001; Ganusov et al. 2002; Gandon 2004; Lively 2010; 91 Moreno-Gámez et al. 2013). However, in the context of emerging diseases, right after 92 the spill-over of the new pathogen into the heterogeneous host population and prior to 93 adaptive evolution to take place, Yates et al. (2006) showed that host heterogeneity has a 94 small effect in the probability of establishing the disease. Very recently, Chabas et al. 95 (2018) showed that evolutionary emergence is more likely to occur when the host 96 population contains intermediate levels of resistant hosts, confirming this prediction using 97 different phages and bacterial hosts with different alterations in the CRISPR/Cas immune 98 systems that conferred the cells with different levels of resistance. 99 In this study we use experimental evolution to explore the effect of host population 100 structure for genes involved in susceptibility to infection in the evolution of 101 infectiousness and virulence of a plant virus; in particular, we want to explore the extent 102 to which host heterogeneity determines the rate of evolution of these two fitness-related 103 traits. According to the above theoretical predictions and experimental observations in 104 other pathosystems, we expect the virus infectiousness and virulence to evolve to lower 105 levels in genetically homogeneous host populations, but at a faster rate, than in maximally 106 genetically diverse host populations.
Load more

Recommended publications
  • A Novel Arabidopsis Pathosystem Reveals Cooperation of Multiple
    www.nature.com/scientificreports OPEN A novel Arabidopsis pathosystem reveals cooperation of multiple hormonal response-pathways in host resistance against the global crop destroyer Macrophomina phaseolina Mercedes M. Schroeder1, Yan Lai1,2, Miwa Shirai1, Natalie Alsalek1,3, Tokuji Tsuchiya 4, Philip Roberts5 & Thomas Eulgem 1* Dubbed as a “global destroyer of crops”, the soil-borne fungus Macrophomina phaseolina (Mp) infects more than 500 plant species including many economically important cash crops. Host defenses against infection by this pathogen are poorly understood. We established interactions between Mp and Arabidopsis thaliana (Arabidopsis) as a model system to quantitatively assess host factors afecting the outcome of Mp infections. Using agar plate-based infection assays with diferent Arabidopsis genotypes, we found signaling mechanisms dependent on the plant hormones ethylene, jasmonic acid and salicylic acid to control host defense against this pathogen. By profling host transcripts in Mp-infected roots of the wild-type Arabidopsis accession Col-0 and ein2/jar1, an ethylene/jasmonic acid-signaling defcient mutant that exhibits enhanced susceptibility to this pathogen, we identifed hundreds of genes potentially contributing to a diverse array of defense responses, which seem coordinated by complex interplay between multiple hormonal response-pathways. Our results establish Mp/Arabidopsis interactions as a useful model pathosystem, allowing for application of the vast genomics-related resources of this versatile model plant to the systematic investigation of previously understudied host defenses against a major crop plant pathogen. Te broad host-spectrum pathogen Macrophomina phaseolina (Mp) is a devastating soil-borne fungus that infects more than 500 plant species1–5. Many of these hosts are economically important crop plants including maize, soybean, canola, cotton, peanut, sunfower and sugar cane5–10.
    [Show full text]
  • The Effects of Pathogen Infection on Nitrogen Remobilization in Arabidopsis Thaliana
    University of Tennessee, Knoxville TRACE: Tennessee Research and Creative Exchange Masters Theses Graduate School 12-2006 The Effects of Pathogen Infection on Nitrogen Remobilization in Arabidopsis thaliana Michelle Ann Boercker University of Tennessee - Knoxville Follow this and additional works at: https://trace.tennessee.edu/utk_gradthes Part of the Ecology and Evolutionary Biology Commons Recommended Citation Boercker, Michelle Ann, "The Effects of Pathogen Infection on Nitrogen Remobilization in Arabidopsis thaliana. " Master's Thesis, University of Tennessee, 2006. https://trace.tennessee.edu/utk_gradthes/1506 This Thesis is brought to you for free and open access by the Graduate School at TRACE: Tennessee Research and Creative Exchange. It has been accepted for inclusion in Masters Theses by an authorized administrator of TRACE: Tennessee Research and Creative Exchange. For more information, please contact [email protected]. To the Graduate Council: I am submitting herewith a thesis written by Michelle Ann Boercker entitled "The Effects of Pathogen Infection on Nitrogen Remobilization in Arabidopsis thaliana." I have examined the final electronic copy of this thesis for form and content and recommend that it be accepted in partial fulfillment of the equirr ements for the degree of Master of Science, with a major in Ecology and Evolutionary Biology. James Fordyce, Major Professor We have read this thesis and recommend its acceptance: Nathan Sanders, Joe Williams Accepted for the Council: Carolyn R. Hodges Vice Provost and Dean of the Graduate School (Original signatures are on file with official studentecor r ds.) To the Graduate Council: I am submitting herewith a thesis written by Michelle Ann Boercker entitled “The Effects of Pathogen Infection on Nitrogen Remobilization in Arabidopsis thaliana.” I have examined the final electronic copy of this thesis for form and content and recommend that it be accepted in partial fulfillment of the requirement for the degree of Master of Science, with a major in Ecology and Evolutionary Biology.
    [Show full text]
  • Rice Hoja Blanca: a Complex Plant–Virus–Vector Pathosystem F.J
    CAB Reviews: Perspectives in Agriculture, Veterinary Science, Nutrition and Natural Resources 2010 5, No. 043 Review Rice hoja blanca: a complex plant–virus–vector pathosystem F.J. Morales* and P.R. Jennings Address: International Centre for Tropical Agriculture, AA 6713, Cali, Colombia. *Correspondence: F.J. Morales. E-mail: [email protected] Received: 30 April 2010 Accepted: 24 June 2010 doi: 10.1079/PAVSNNR20105043 The electronic version of this article is the definitive one. It is located here: http://www.cabi.org/cabreviews g CAB International 2009 (Online ISSN 1749-8848) Abstract Rice hoja blanca (RHB; white leaf) devastated rice (Oryza sativa) plantings in tropical America for half a century, before scientists could either identify its causal agent or understand the nature of its cyclical epidemics. The association of the planthopper Tagosodes orizicolus with RHB outbreaks, 20 years after its emergence in South America, suggested the existence of a viral pathogen. However, T. orizicolus could also cause severe direct feeding damage (hopperburn) to rice in the absence of hoja blanca, and breeders promptly realized that the genetic basis of resistance to these problems was different. Furthermore, it was observed that the causal agent of RHB could only be trans- mitted by a relatively low proportion of the individuals in any given population of T. orizicolus and that the pathogen was transovarially transmitted to the progeny of the planthopper vectors, affecting their normal biology. An international rice germplasm screening effort was initiated in the late 1950s to identify sources of resistance against RHB and the direct feeding damage caused by T.
    [Show full text]
  • Breeding Poplars for Disease Resistance
    Breeding poplars , ' for 56 disease resistance . , ," . { " , .' ,./' -. .~. , FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS Breeding poplars for disease resistance The designations employed and the presentation of material in this publication do not imply the expression of any opinion whatsoever on the part of the Food and Agriculture Organilation of the United Nations concerning the legal status of any country. territory. city or area or of its authorities. or concerning the delimitation of its frontiers or boundaries. M-32 ISBN 92-5-102214-3 All rights reserved. No part of this publication may be reproduced. stored in a retrieval system. or transmitted in any form or by any means, electronic. mechanical, photocopying or otherwise, without the prior permission of the copyright ·owner. Applications for such permission, with a statement of the purpose and extent of the reproduction, should be addressed to the Director, Publications Division, Food and Agriculture Organization of the United Nations, Via delle Terme di Caracalla, 00100 Rome, Italy. - iii - FOREWORD Poplars are amongst the oldest contemporary angiosperm genera with over 125 species recorded as fossils and 30 to 40 species ~xisting today.They are dioecious and are more frequently propagated from cuttings than seed, Lending themseLves to the creation of cLones and the cuLtivation of recognizabLe and cLonally reproducible hybrids. They have Long been cuLtivated in Asia as welL as in Europe but their more recent deveLopment dates from the 18th century when North American poplars were imported to form hybrids with European species, a trend which is now extending to West and East Asia. Their utiLity lies in ~he frequently rapid growth potentiaL of species, their hybrids and certain clones as weLL as the wide use to which popLars can be put to provide industriaL wood, fodder for animaLs, sheLter, energy and timber for domestic and farm use.
    [Show full text]
  • Concepts in Plant Disease Resistance
    REVISÃO / REVIEW CONCEPTS IN PLANT DISEASE RESISTANCE FRANCISCO XAVIER RIBEIRO DO VALE1, J. E. PARLEVLIET2 & LAÉRCIO ZAMBOLIM1 1Departamento de Fitopatologia, Universidade Federal de Viçosa, CEP 36571-000, Viçosa, MG, Brasil, e-mail: [email protected]; 2Department of Plant Breeding (IVP), Wageningen Agricultural University, P.O. Box 386, 6700 AJ Wageningen, The Netherlands (Aceito para publicação em 13/08/2001) Autor para correspondência: Francisco Xavier Ribeiro do Vale RIBEIRO DO VALE, F.X., PARLEVLIET, J.E. & ZAMBOLIM, L. Concepts in plant disease resistance. Fitopatologia Brasileira 26:577- 589. 2001. ABSTRACT Resistance to nearly all pathogens occurs abundantly Race-specificity is not the cause of elusive resistance but the in our crops. Much of the resistance exploited by breeders is consequence of it. Understanding acquired resistance may of the major gene type. Polygenic resistance, although used open interesting approaches to control pathogens. This is even much less, is even more abundantly available. Many types of truer for molecular techniques, which already represent an resistance are highly elusive, the pathogen apparently adapting enourmously wide range of possibilities. Resistance obtained very easily them. Other types of resistance, the so-called through transformation is often of the quantitative type and durable resistance, remain effective much longer. The elusive may be durable in most cases. resistance is invariably of the monogenic type and usually of Key words: types of resistance; genetics of resistance; the hypersensitive type directed against specialised pathogens. acquired resistance. RESUMO Conceitos em resistência de plantas a doenças Na natureza a resistência à maioria das doenças ocorre tência durável. A resistência temporária é invariavelmente nas culturas.
    [Show full text]
  • Systems Approaches in Epidemiology and Plant Disease Managetnent
    Neth. J. Pl. Path. 99 (1993) Supplement 3: 161-171 Systems approaches in epidemiology and plant disease managetnent R. RABBINGE, W.A.H. ROSSING and W. VANDERWERF Department of Theoretical Production Ecology, Wageningen Agricultural University, P.O. Box 430, 6700 AK Wageningen, the Netherlands Accepted 28 October 1993 Abstract This contribution to Zadoks' liber amicorum reviews the developments in quantitative epidemio­ logy during the last decades. It elucidates the progress in this field and shows how empirical crop protection with many phenomenological aspects transformed into a science-based (inter)discipline. The availability of experimental tools and the rapid development and introduction of computers enabled the application of systems approaches which stimulated a revolution in thinking and caused · a considerable improvement of strategic and tactical decision making in crop protection. Zadoks played a crucial role in that development. Additional keyll'ords: simulation, modelling, crop protection Introduction Zadaks' contrilmtionto l'jJidemiology and plant disease management From the time of his arrival in Wageningen in 1956, Zadoks contributed to the systems approach in crop protection. As a fresh scientific worker in crop protection, he was aware of the necessity to determine fundamental epidemiological parameters such as infectious period, latency period and spore production under well-defined conditions, to better understand epidemiology of plant pathogenic fungi under field situations. When he started as a professor at the university, he received a so-called bride's contribution of one million Dutch guilders, an unbelievable amount nowadays, to construct climate cabinets and climate rooms that allowed him to undertake these studies. Zadoks' studies of funda­ mental epidemiological parameters laid the basis for his quantitative understanding of stripe rust epidemics in the field.
    [Show full text]
  • Aphid–Plant–Phytovirus Pathosystems: Influencing Factors from Vector Behaviour to Virus Spread
    agriculture Review Aphid–Plant–Phytovirus Pathosystems: Influencing Factors from Vector Behaviour to Virus Spread Junior Corneille Fingu-Mabola * and Frédéric Francis Entomologie Fonctionnelle et Évolutive, Terra, Gembloux Agro-Bio Tech, Liège-Université, Passage des Déportés 2, 5030 Gembloux, Belgium; [email protected] * Correspondence: jcfi[email protected] Abstract: Aphids are responsible for the spread of more than half of the known phytovirus species. Virus transmission within the plant–aphid–phytovirus pathosystem depends on vector mobility which allows the aphid to reach its host plant and on vector efficiency in terms of ability to transmit phytoviruses. However, several other factors can influence the phytoviruses transmission process and have significant epidemiological consequences. In this review, we aimed to analyse the aphid behaviours and influencing factors affecting phytovirus spread. We discussed the impact of vector host-seeking and dispersal behaviours mostly involved in aphid-born phytovirus spread but also the effect of feeding behaviours and life history traits involved in plant–aphid–phytovirus relationships on vector performances. We also noted that these behaviours are influenced by factors inherent to the interactions between pathosystem components (mode of transmission of phytoviruses, vector efficiency, plant resistance, ... ) and several biological, biochemical, chemical or physical factors related to the environment of these pathosystem components, most of them being manipulated as means to control vector-borne diseases in the crop fields. Citation: Fingu-Mabola, J.C.; Francis, Keywords: host selection; plant–aphid–virus pathosystem; vector activity; vector-born virus; F. Aphid–Plant–Phytovirus vectorial transmission efficiency Pathosystems: Influencing Factors from Vector Behaviour to Virus Spread. Agriculture 2021, 11, 502.
    [Show full text]
  • Discovery of Interaction-Related Srnas and Their Targets in the Brachypodium Distachyon and Magnaporthe Oryzae Pathosystem
    bioRxiv preprint doi: https://doi.org/10.1101/631945; this version posted May 24, 2019. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY 4.0 International license. 1 Discovery of interaction-related sRNAs and their targets in the Brachypodium 2 distachyon and Magnaporthe oryzae pathosystem 3 Silvia Zanini1, Ena Šečić1, Tobias Busche2, Jörn Kalinowski2, Karl-Heinz Kogel1* 4 1Institute of Phytopathology, Centre for BioSystems, Land Use and Nutrition, Justus Liebig University, 5 Heinrich-Buff-Ring 26-32, D-35392, Giessen, Germany 6 2Center for Biotechnology, University Bielefeld, Universitätsstraße 27, D-33615 Bielefeld, Germany 7 8 Running title: 9 sRNAs in the Bd-Mo pathosystem 10 11 Email addresses: 12 [email protected] 13 [email protected] 14 [email protected] 15 [email protected] 16 [email protected] 17 18 *Correspondence to 19 [email protected] 20 21 Keywords: 22 Small RNA, cross-kingdom RNAi, bidirectional communication, RNA targets, plant disease, 23 virulence 24 25 Abstract 1 bioRxiv preprint doi: https://doi.org/10.1101/631945; this version posted May 24, 2019. The copyright holder for this preprint (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made available under aCC-BY 4.0 International license. 26 Microbial pathogens secrete small RNA (sRNA) effectors into plant hosts to aid infection by 27 silencing transcripts of immunity and signaling-related genes through RNA interference (RNAi).
    [Show full text]
  • Interspecific Interactions Within a Vector-Borne Complex Are Influenced by a Co-Occurring Pathosystem
    www.nature.com/scientificreports OPEN Interspecifc interactions within a vector‑borne complex are infuenced by a co‑occurring pathosystem Regina K. Cruzado‑Gutiérrez1,2,7, Rohollah Sadeghi2,7, Sean M. Prager3, Clare L. Casteel4, Jessica Parker2, Erik J. Wenninger5, William J. Price6, Nilsa A. Bosque‑Pérez2, Alexander V. Karasev2 & Arash Rashed1,2* Potato virus Y (PVY) and zebra chip (ZC) disease are major threats to solanaceous crop production in North America. PVY can be spread by aphid vectors and through vegetative propagation in potatoes. ZC is associated with “Candidatus Liberibacter solanacearum” (Lso), which is transmitted by the tomato/potato psyllid, Bactericera cockerelli Šulc (Hemiptera: Triozidae). As these two pathosystems may co‑occur, we studied whether the presence of one virus strain, PVY°, afected the host preference, oviposition, and egg hatch rate of Lso‑free or Lso‑carrying psyllids in tomato plants. We also examined whether PVY infection infuenced Lso transmission success by psyllids, Lso titer and plant chemistry (amino acids, sugars, and phytohormones). Lso‑carrying psyllids showed a preference toward healthy hosts, whereas the Lso‑free psyllids preferentially settled on the PVY‑infected tomatoes. Oviposition of the Lso‑carrying psyllids was lower on PVY‑infected than healthy tomatoes, but Lso transmission, titer, and psyllid egg hatch were not signifcantly afected by PVY. The induction of salicylic acid and its related responses, and not nutritional losses, may explain the reduced attractiveness of the PVY‑infected host to the Lso‑carrying psyllids. Although our study demonstrated that pre‑existing PVY infection can reduce oviposition by the Lso‑carrying vector, the preference of the Lso‑carrying psyllids to settle on healthy hosts could contribute to Lso spread to healthy plants in the presence of PVY infection in a feld.
    [Show full text]
  • Optimization of Pathogenicity Assays to Study the Arabidopsis Thaliana–Xanthomonas Campestris Pv
    MOLECULAR PLANT PATHOLOGY (2005) 6(3), 327–333 DOI: 10.1111/J.1364-3703.2005.00287.X ShortBlackwell Publishing, Ltd. communication Optimization of pathogenicity assays to study the Arabidopsis thaliana–Xanthomonas campestris pv. campestris pathosystem DAMIEN MEYER, EMMANUELLE LAUBER, DOMINIQUE ROBY, MATTHIEU ARLAT AND THOMAS KROJ* Laboratoire des Interactions Plantes-Microorganismes, UMR CNRS/INRA 2594, BP52627, 31326 Castanet-Tolosan, France provided (Katagiri et al., 2002; Quirino and Bent, 2003). By con- SUMMARY trast, our knowledge about the interaction between Arabidopsis The cruciferous weed Arabidopsis thaliana and the causal agent and Xanthomonas campestris pv. campestris (Xcc), which was of black rot disease of Crucifers Xanthomonas campestris pv. described even before the Arabidopsis–P. syringae system campestris (Xcc) are both model organisms in plant pathology. (Simpson and Johnson, 1990), is still rudimentary (Buell, 2002). Their interaction has been studied successfully in the past, but Many Xanthomonads including Xcc have, however, been inten- these investigations suffered from high variability. In the present sively studied and Xcc is a natural pathogen of cruciferous plants study, we describe an improved Arabidopsis–Xcc pathosystem and provokes considerable economical loss by causing black rot that is based on a wound inoculation procedure. We show that diseases (Alvarez, 2000; Onsando, 1992; Williams, 1980). More- after wound inoculation, Xcc colonizes the vascular system of over, the genome sequence of three different Xanthomonas spe- Arabidopsis leaves and causes typical black rot symptoms in a cies/strains and two closely related Xylella fastidiosa strains are compatible interaction, while in an incompatible interaction publicly available, which makes Xanthomonas an interesting plant bacterial multiplication is inhibited.
    [Show full text]
  • Antibacterial FANA Oligonucleotides As a Novel Approach for Managing the Huanglongbing Pathosystem Andrés F
    www.nature.com/scientificreports OPEN Antibacterial FANA oligonucleotides as a novel approach for managing the Huanglongbing pathosystem Andrés F. Sandoval‑Mojica1,3, Wayne B. Hunter2, Veenu Aishwarya3, Sylvia Bonilla1,3 & Kirsten S. Pelz‑Stelinski1* Candidatus Liberibacter asiaticus (CLas), a bacterium transmitted by the Asian citrus psyllid, Diaphorina citri, is the causal agent of citrus greening disease, or Huanglongbng (HLB). Currently, vector population suppression with insecticides and tree removal are the most efective strategies for managing the HLB pathosystem. In this study, we assessed the bactericidal capabilities of 2′‑deoxy‑ 2′‑fuoro‑d‑arabinonucleic acid antisense oligonucleotides (FANA ASO) both in vitro and in vivo by (1) confrming their capacity to penetrate insect cells, (2) silencing bacterial essential genes, and (3) quantifying reductions in bacterial titer and D. citri transmission. We confrmed that FANA ASO are able to penetrate insect cells without the use of a delivery agent. Expression of an essential gene in the D. citri endosymbiont, Wolbachia (wDi), signifcantly decreased by 30% following incubation with a wDi‑specifc FANA ASO. Viability of isolated wDi cells also decreased in response to the FANA ASO treatment. Delivery of a CLas‑specifc FANA ASO to infected adult D. citri in feeding assays resulted in signifcant silencing of a CLas essential gene. CLas relative density and transmission were signifcantly lower among D. citri fed FANA ASO in diet compared to untreated insects. Root infusions of a CLas‑ specifc FANA ASO into infected Citrus trees signifcantly reduced CLas titer during a 30‑day trial. Our results suggest that FANA ASO targeting insect‑transmitted plant bacteria or insect endosymbionts may be useful tool for integrated management of agricultural pathogens.
    [Show full text]
  • Navigating Complexity to Breed Disease-Resistant Crops
    REVIEWS Navigating complexity to breed disease-resistant crops Rebecca Nelson1, Tyr Wiesner-Hanks1, Randall Wisser2 and Peter Balint-Kurti3 Abstract | Plant diseases are responsible for substantial crop losses each year and pose a threat to global food security and agricultural sustainability. Improving crop resistance to pathogens through breeding is an environmentally sound method for managing disease and minimizing these losses. However, it is challenging to breed varieties with resistance that is effective, stable and broad-spectrum. Recent advances in genetic and genomic technologies have contributed to a better understanding of the complexity of host–pathogen interactions and have identified some of the genes and mechanisms that underlie resistance. This new knowledge is benefiting crop improvement through better-informed breeding strategies that utilize diverse forms of resistance at different scales, from the genome of a single plant to the plant varieties deployed across a region. Landraces An estimated 13% of global crop yields are lost to dis­ resistance breeding process. When genes and genomic Traditional plant varieties that eases annually1,2. The extent of these losses varies by loci that confer disease resistance are identified, they have been developed through crop and by region but is greatest in the tropics and sub­ can be assessed in terms of the strength of their effect, informal (farmer-based) tropics where conditions favour disease development1. their race specificity and their potential contributions breeding. Although chemical control is an efficient method of dis­ to durability. At the genotype level, the performance of Germplasm ease management, overall crop losses have not declined resistance is influenced by the number of resistance Living material, such as seeds over the past half century, while pesticide use has drama­ genes and their specific combination in the host.
    [Show full text]