DOCSLIB.ORG

Disease Resistance in Ornamental Plants

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Disease Resistance in Ornamental Plants Disease resistance in ornamental plants - Transformation of Symphyotrichum novi-belgii with powdery mildew resistance genes Eline Kirk Mørk PhD thesis Department of Food Science, Aarhus University, October 2011 1 Disease resistance in ornamental plants - Transformation of Symphyotrichum novi-belgii with powdery mildew resistance genes PhD thesis Eline Kirk Mørk, Department of Food Science, Aarhus University Supervisors Senior Scientist Karen Koefoed Petersen, Department of Food Science, Aarhus University Senior Scientist Kell Kristiansen Associate Professor Henrik Brinch-Pedersen, Department of Genetics and Biotechnology, Aarhus University 2 Preface This thesis has been submitted to Aarhus University as part of my fulfilment of the requirements to obtain the degree of Doctor of Philosophy. The original research presented here was conducted in the period February 2008 to October 2011 at the Department of Horticulture (Now Department of Food Science) with a 9 months maternity leave in 2009. The Department belongs to the Faculty of Science and Technology (Faculty of Agricultural Science at the onset of the project), Aarhus University. In addition I spent 8 months in 2008 together with the research unit Molecular Genetics and Biotechnology part of the former Institute of Genetics and Biotechnology, Research Centre Flakkebjerg, Aarhus University to get introduced to cloning and molecular analysis. The thesis consists of summaries in English and Danish, an introduction followed by a literature review, four papers (two published articles and two manuscripts), a discussion of the findings, a conclusion and perspectives of the work. Along the road of this project I have been supported by a number of people. First I would like to thank Karen Koefoed Petersen for her guidance and the constant open door. I am grateful to my other supervisors Kell Kristiansen and Henrik-Brinch-Pedersen for the valuable discussions and advice given to me when needed. I would also like to thank Post-Doc Thomas Sundelin for being more than just a teacher of a course and Post-Doc Sine Hovbye Topp for letting me follow her and learn her molecular magic, both from Faculty of Life Sciences, University of Copenhagen. Furthermore I would like to thank all colleagues at the old Department of Horticulture, Aarhus University for their helpfulness and a pleasant cheerful working atmosphere. A special thanks to Sylvia Travers and Eleftheria Stavridou for their friendship and encouragements. Finally, I wish to thank family and friends for their support and encouragement during my study, with a special thanks to my husband and son for sharing me with the project. 3 Table of Content PREFACE ..................................................................................................................................................................... 3 TABLE OF CONTENT .................................................................................................................................................... 4 SUMMARY .................................................................................................................................................................. 6 RESUMÉ ...................................................................................................................................................................... 8 LIST OF ABBREVIATIONS ............................................................................................................................................10 1. INTRODUCTION ................................................................................................................................................14 2. TRANSFORMATION OF ORNAMENTALS ............................................................................................................16 2.1 TRANSFORMATION PROTOCOLS .................................................................................................................................. 18 2.1.1 Flower Colour ............................................................................................................................................ 18 2.1.2 Flower and Leaf Longevity ........................................................................................................................ 21 2.1.3 Flowering Time .......................................................................................................................................... 22 2.1.4 Plant Size and Architecture ....................................................................................................................... 23 2.1.5 Disease Resistance .................................................................................................................................... 25 3. THE PLANT IMMUNE SYSTEM ...........................................................................................................................29 3.1 INNATE IMMUNITY ................................................................................................................................................... 29 3.2 RESPONSES TO PATHOGEN RECOGNITION ..................................................................................................................... 33 3.3 TRANSCRIPTIONAL REGULATION OF PLANT DEFENCE RESPONSES ...................................................................................... 35 3.4 INDUCED RESISTANCE ............................................................................................................................................... 37 4. SELECTED GENES...............................................................................................................................................39 4.1 ACE-AMP1 ........................................................................................................................................................... 39 4.1.1 The function of Ace-AMP1 inside the cell .................................................................................................. 39 4.1.2 The function of Ace-AMP1 outside the cell ............................................................................................... 40 4.2 RCC2 ................................................................................................................................................................... 43 4.3 VVWRKY1 ............................................................................................................................................................ 46 4.3.1 WRKY transcription factors ....................................................................................................................... 46 4.3.2 VvWRKY transcription factors ................................................................................................................... 48 5. POWDERY MILDEW ..........................................................................................................................................51 5.1 INFECTION.............................................................................................................................................................. 51 5.2 REPRODUCTION ...................................................................................................................................................... 53 5.2.1 Asexual Reproduction ............................................................................................................................... 53 5.2.2 Sexual Reproduction ................................................................................................................................. 55 4 5.3 PERENNATION ........................................................................................................................................................ 56 5.4 TAXONOMY OF GOLOVINOMYCES ............................................................................................................................... 56 6. PAPER 1: FIRST REPORT OF GOLOVINOMYCES CICHORACEARUM AS THE CAUSAL AGENT OF POWDERY MILDEW ON SYMPHYOTRICHUM NOVI-BELGII (SYN. ASTER NOVI-BELGII) IN DENMARK ...........................................59 7. PAPER 2: (MANUSCRIPT) ARTEMISIA ANNUA AS NEW HOST FOR GOLOVINOMYCES SP CAUSING POWDERY MILDEW ....................................................................................................................................................................62 8. PAPER 3: AN EFFICIENT PROTOCOL FOR REGENERATION AND TRANSFORMATION OF SYMPHYOTRICHUM NOVI-BELGII ...............................................................................................................................................................65 9. PAPER 4: (MANUSCRIPT) POSITIVE EFFECT OF TRANSGENES ON POWDERY MILDEW RESISTANCE IN SYMPHYOTRICHUM NOVI-BELGII UNDER GREENHOUSE CONDITIONS .......................................................................78 10. GENERAL DISCUSSION AND PERSPECTIVES .......................................................................................................96 10.1 CLASSIFICATION OF GOLOVINOMYCES SP. ................................................................................................................ 96 10.2 TRANSFORMATION OF SYMPHYOTRICHUM NOVI-BELGII ............................................................................................ 101 10.3 GENES OF INTEREST ..........................................................................................................................................
Load more

Recommended publications
  • Diplocarpon Rosae) Genetic Diversity in Eastern North America Using Amplified Fragment Length Polymorphism and Implications for Resistance Screening
    J. AMER.SOC.HORT.SCI. 132(4):534–540. 2007. Distribution of Rose Black Spot (Diplocarpon rosae) Genetic Diversity in Eastern North America Using Amplified Fragment Length Polymorphism and Implications for Resistance Screening Vance M. Whitaker and Stan C. Hokanson1 Department of Horticultural Science, University of Minnesota, 258 Alderman Hall, 1970 Folwell Avenue, St. Paul, MN 55108 James Bradeen Department of Plant Pathology, University of Minnesota, 495 Borlaug Hall, 1991 Upper Buford Circle, St. Paul, MN 55108 ADDITIONAL INDEX WORDS. AMOVA, dendrogram, fungal isolate, Jaccard’s coefficient, pathogenic race, principal component analysis ABSTRACT. Black spot, incited by the fungus Diplocarpon rosae Wolf, is the most significant disease problem of landscape roses (Rosa hybrida L.) worldwide. The documented presence of pathogenic races necessitates that rose breeders screen germplasm with isolates that represent the range of D. rosae diversity for their target region. The objectives of this study were to characterize the genetic diversity of single-spore isolates from eastern North America and to examine their distribution according to geographic origin, host of origin, and race. Fifty isolates of D. rosae were collected from roses representing multiple horticultural classes in disparate locations across eastern North America and analyzed by amplified fragment length polymorphism. Considerable marker diversity among isolates was discovered, although phenetic and cladistic analyses revealed no significant clustering according to host of origin or race. Some clustering within collection locations suggested short-distance dispersal through asexual conidia. Lack of clustering resulting from geographic origin was consistent with movement of D. rosae on vegetatively propagated roses. Results suggest that field screening for black spot resistance in multiple locations may not be necessary; however, controlled inoculations with single-spore isolates representing known races is desirable as a result of the inherent limitations of field screening.
    [Show full text]
  • Apple Powdery Mildew Caused by Podosphaera Leucotricha: Some Aspects of Biology
    International Journal of Horticultural Science 2013, 19 (3–4): 19–23. Agroinform Publishing House, Budapest, Printed in Hungary ISSN 1585-0404 Apple powdery mildew caused by Podosphaera leucotricha: some aspects of biology Holb, I.J. University of Debrecen, Faculty of Agriculture, Institute of Horticulture, 138. Böszörményi str., Debrecen, H-4032, Hungary ([email protected]) Summary: Apple powdery mildew (Podoshphaera leucorticha) occurs wherever apples are grown. One of the most important fungal disease of apple which causing severe econimic loss on susceptible apple cultivars. Biology of the pathogen is widely investigated all over the world in the past 100 years. In this review, a summary from this enormous research is made for biology of apple powdery mildew in the following aspects: geographical distribution, morphology, taxonomy of the causal agent, symptoms, host susceptibility, resistance durability and disease cycle. Key words: Malus x domestica Bork., apple powdery mildew, Podoshphaera leucorticha, geographical distribution, symptoms, host susceptibility, disease cycle, biology Introduction branched appendages at tip and chasmothecium (formerly cleistothecium) with one ascus (Salmon, 1900). The Apple powdery mildew (Podoshphaera leucorticha) is a Erysiphaceae are called obligate parasites. On conventional wordwide known fungal pathogen of apple. A key important media, such as potato dextrose agar, powdery mildew conidia fungal disease of apple which causing severe econimic may form short germ tubes with septa (Yossifovitch, 1923), loss on susceptible cultivars in every years where apple are but these germ tubes soon die. grown (Hickey & Yoder, 1990). Biology of the pathogen Podosphaera leucotricha (Ell. & Ev.) E. S. Salmon is widely investigated all over the world in the past 100 (anamorph Oidium farinosum Cooke), an ascomycetous years.
    [Show full text]
  • Prediction of Disease Damage, Determination of Pathogen
    PREDICTION OF DISEASE DAMAGE, DETERMINATION OF PATHOGEN SURVIVAL REGIONS, AND CHARACTERIZATION OF INTERNATIONAL COLLECTIONS OF WHEAT STRIPE RUST By DIPAK SHARMA-POUDYAL A dissertation submitted in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY WASHINGTON STATE UNIVERSITY Department of Plant Pathology MAY 2012 To the Faculty of Washington State University: The members of the Committee appointed to examine the dissertation of DIPAK SHARMA-POUDYAL find it satisfactory and recommend that it be accepted. Xianming Chen, Ph.D., Chair Dennis A. Johnson, Ph.D. Kulvinder Gill, Ph.D. Timothy D. Murray, Ph.D. ii ACKNOWLEDGEMENTS I would like to express my sincere gratitude to Dr. Xianming Chen for his invaluable guidance, moral support, and encouragement throughout the course of the study. I would like to thank Drs. Dennis A. Johnson, Kulvinder Gill, and Timothy D. Murray for serving in my committee and their valuable suggestions for my project. I also like to thank Dr. Mark Evans, Department of Statistics, for his statistical advice on model development and selection. I am grateful to Dr. Richard A. Rupp, Department of Crop and Soil Sciences, for his expert advice on using GIS techniques. I am thankful to many wheat scientists throughout the world for providing stripe rust samples. Thanks are also extended to Drs. Anmin Wan, Kent Evans, and Meinan Wang for their kind help in the stripe rust experiments. Special thanks to Dr. Deven See for allowing me to use the genotyping facilities in his lab. Suggestions on data analyses by Dr. Tobin Peever are highly appreciated. I also like to thank my fellow graduate students, especially Jeremiah Dung, Ebrahiem Babiker, Jinita Sthapit, Lydia Tymon, Renuka Attanayake, and Shyam Kandel for their help in many ways.
    [Show full text]
  • APPROVED: Late Ul
    APPLE POWDERY MILDEW: LITERATURE AND RESEARCH OVERVIEW by Anita Marie Scamack Project submitted to the Faculty of the Virginia Polytechnic Institute and State University in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE in Plant Pathology APPROVED: Late Ul . Yoder¢ Chairman c Re P7/ Sthres , Ko-chairman May, 1991 Blacksburg, Virginia \ a, ann ann SO5g VEST 12Qy LO7 APPLE POWDERY MILDEW: LITERATURE AND RESEARCH OVERVIEW by Anita Marie Scamack Committee Chairman: Keith S. Yoder Plant Pathology (ABSTRACT) Apple powdery mildew, caused by the fungus Podosphaera leucotricha (Ell. and Everh.) Salm., is a disease found in apple growing regions world-wide, and is economically important in many of them. Most of the research on this pathogen pertains to various methods of control, particularly with fungicides and host resistance. Fungicide effectiveness and development of new fungicides have been most prominent. A considerable amount of research has been done in epidemiology. Host resistance genetics and mechanisms, components, and development of resistant cultivars have also been emphasized. Aspects of research on apple powdery mildew that have not been explored in as much depth are also reviewed. Some of these areas include the role of cleistothecia and ascospores in life and disease cycles, heterothallism versus homothallism, and growth of the fungus on artificial media. Additional research needs from each aspect are proposed. This report is based ona comprehensive review of the current literature on apple powdery mildew. AKNOWLWEDGEMENTS With much gratitude, I would like to thank mv committee members for their various roles in my scholastic endeavors. I am grateful to Dr.
    [Show full text]
  • An Annotated Catalogue of the Fungal Biota of the Roztocze Upland Monika KOZŁOWSKA, Wiesław MUŁENKO Marcin ANUSIEWICZ, Magda MAMCZARZ
    An Annotated Catalogue of the Fungal Biota of the Roztocze Upland Fungal Biota of the An Annotated Catalogue of the Monika KOZŁOWSKA, Wiesław MUŁENKO Marcin ANUSIEWICZ, Magda MAMCZARZ An Annotated Catalogue of the Fungal Biota of the Roztocze Upland Richness, Diversity and Distribution MARIA CURIE-SkłODOWSKA UNIVERSITY PRESS POLISH BOTANICAL SOCIETY Grzyby_okladka.indd 6 11.02.2019 14:52:24 An Annotated Catalogue of the Fungal Biota of the Roztocze Upland Richness, Diversity and Distribution Monika KOZŁOWSKA, Wiesław MUŁENKO Marcin ANUSIEWICZ, Magda MAMCZARZ An Annotated Catalogue of the Fungal Biota of the Roztocze Upland Richness, Diversity and Distribution MARIA CURIE-SkłODOWSKA UNIVERSITY PRESS POLISH BOTANICAL SOCIETY LUBLIN 2019 REVIEWER Dr hab. Małgorzata Ruszkiewicz-Michalska COVER DESIN, TYPESETTING Studio Format © Te Authors, 2019 © Maria Curie-Skłodowska University Press, Lublin 2019 ISBN 978-83-227-9164-6 ISBN 978-83-950171-8-6 ISBN 978-83-950171-9-3 (online) PUBLISHER Polish Botanical Society Al. Ujazdowskie 4, 00-478 Warsaw, Poland pbsociety.org.pl Maria Curie-Skłodowska University Press 20-031 Lublin, ul. Idziego Radziszewskiego 11 tel. (81) 537 53 04 wydawnictwo.umcs.eu [email protected] Sales Department tel. / fax (81) 537 53 02 Internet bookshop: wydawnictwo.umcs.eu [email protected] PRINTED IN POLAND, by „Elpil”, ul. Artyleryjska 11, 08-110 Siedlce AUTHOR’S AFFILIATION Department of Botany and Mycology, Maria Curie-Skłodowska University, Lublin Monika Kozłowska, [email protected]; Wiesław
    [Show full text]
  • Myconet Volume 14 Part One. Outine of Ascomycota – 2009 Part Two
    (topsheet) Myconet Volume 14 Part One. Outine of Ascomycota – 2009 Part Two. Notes on ascomycete systematics. Nos. 4751 – 5113. Fieldiana, Botany H. Thorsten Lumbsch Dept. of Botany Field Museum 1400 S. Lake Shore Dr. Chicago, IL 60605 (312) 665-7881 fax: 312-665-7158 e-mail: [email protected] Sabine M. Huhndorf Dept. of Botany Field Museum 1400 S. Lake Shore Dr. Chicago, IL 60605 (312) 665-7855 fax: 312-665-7158 e-mail: [email protected] 1 (cover page) FIELDIANA Botany NEW SERIES NO 00 Myconet Volume 14 Part One. Outine of Ascomycota – 2009 Part Two. Notes on ascomycete systematics. Nos. 4751 – 5113 H. Thorsten Lumbsch Sabine M. Huhndorf [Date] Publication 0000 PUBLISHED BY THE FIELD MUSEUM OF NATURAL HISTORY 2 Table of Contents Abstract Part One. Outline of Ascomycota - 2009 Introduction Literature Cited Index to Ascomycota Subphylum Taphrinomycotina Class Neolectomycetes Class Pneumocystidomycetes Class Schizosaccharomycetes Class Taphrinomycetes Subphylum Saccharomycotina Class Saccharomycetes Subphylum Pezizomycotina Class Arthoniomycetes Class Dothideomycetes Subclass Dothideomycetidae Subclass Pleosporomycetidae Dothideomycetes incertae sedis: orders, families, genera Class Eurotiomycetes Subclass Chaetothyriomycetidae Subclass Eurotiomycetidae Subclass Mycocaliciomycetidae Class Geoglossomycetes Class Laboulbeniomycetes Class Lecanoromycetes Subclass Acarosporomycetidae Subclass Lecanoromycetidae Subclass Ostropomycetidae 3 Lecanoromycetes incertae sedis: orders, genera Class Leotiomycetes Leotiomycetes incertae sedis: families, genera Class Lichinomycetes Class Orbiliomycetes Class Pezizomycetes Class Sordariomycetes Subclass Hypocreomycetidae Subclass Sordariomycetidae Subclass Xylariomycetidae Sordariomycetes incertae sedis: orders, families, genera Pezizomycotina incertae sedis: orders, families Part Two. Notes on ascomycete systematics. Nos. 4751 – 5113 Introduction Literature Cited 4 Abstract Part One presents the current classification that includes all accepted genera and higher taxa above the generic level in the phylum Ascomycota.
    [Show full text]
  • <I>Erysiphaceae</I>
    MYCOTAXON Volume 111, pp. 251–256 January–March 2010 A new species and a new record of Erysiphaceae from China Tie-zhi Liu & Hui-min Tian [email protected] Department of Life Sciences, Chifeng College Chifeng 024000, Inner Mongolia, China Abstract—The new species Podosphaera setacea on Crataegus sanguinea (Rosaceae) in China, intermediate between species of Podosphaera sect. Podosphaera and sect. Sphaerotheca, is described, illustrated, and compared with the morphologically similar species Podosphaera tridactyla, P. ferruginea and P. spiraeae. A new record for China, Erysiphe buhrii, is recorded on the new host species Stellaria dichotoma var. lanceolata. Key words—Erysiphales, powdery mildews, taxonomy Introduction Several interesting specimens of powdery mildew fungi were collected in Chifeng City, Inner Mongolia Autonomous Region, in the north of China in 2008. One of them was a species of Podosphaera Kunze on Crataegus sanguinea resembling an immature collection of P. tridactyla (Wallr.) de Bary (Podosphaera sect. Podosphaera) with each appendage bearing a simple, unbranched apex. However, asci and ascospores were fully developed and mature, suggesting that the appendages in this species remain unbranched. Furthermore, P. tridactyla does not occur on Crataegus spp. The Chinese species on Crataegus has been compared with other Podosphaera species on Rosaceae and was determined to be a distinct, new species. Another specimen represented a new record for China, viz. Erysiphe buhrii on Stellaria dichotoma var. lanceolata, a new host for this species. Materials and methods Material was mounted in distilled water and examined using 100X oil immersion objectives (bright field and phase contrast), but without any staining, using standard light microscopy.
    [Show full text]
  • Podosphaera Leucotricha) Infection
    International Journal of Molecular Sciences Article Transcriptome Analysis of Apple Leaves in Response to Powdery Mildew (Podosphaera leucotricha) Infection Xiaomin Tian 1,2, Li Zhang 1,2, Shuaishuai Feng 1,2, Zhengyang Zhao 1,2, Xiping Wang 1,2,* and Hua Gao 1,2,* 1 State Key Laboratory of Crop Stress Biology in Arid Areas, College of Horticulture, Northwest A&F University, Yangling 712100, China; [email protected] (X.T.); [email protected] (L.Z.); [email protected] (S.F.); [email protected] (Z.Z.) 2 Key Laboratory of Horticultural Plant Biology and Germplasm Innovation in Northwest China, Ministry of Agriculture, Northwest A&F University, Yangling 712100, China * Correspondence: [email protected] (X.W.); [email protected] (H.G.); Tel.: +86-29-87082129 (X.W.); +86-29-87082613 (H.G.) Received: 21 March 2019; Accepted: 6 May 2019; Published: 10 May 2019 Abstract: Apple (Malus domestica Borkh.) is one of the most important cultivated tree fruit × crops worldwide. However, sustainable apple production is threatened by powdery mildew (PM) disease, which is caused by the obligate biotrophic fungus Podosphaera leucotricha. To gain insight into the molecular basis of the PM infection and disease progression, RNA-based transcriptional profiling (RNA-seq) was used to identify differentially expressed genes (DEGs) in apples following inoculation with P. leucotricha. Four RNA-seq libraries were constructed comprising a total of 214 Gb of high-quality sequence. 1177 DEGs (661 upregulated and 629 downregulated) have been identified according to the criteria of a ratio of infection/control fold change > 2, and a false discovery rate (FDR) < 0.001.
    [Show full text]
  • Redalyc.Powdery Mildews in Agricultural Crops of Sinaloa: Current Status on Their Identification and Future Research Lines
    Revista Mexicana de Fitopatología E-ISSN: 2007-8080 [email protected] Sociedad Mexicana de Fitopatología, A.C. México Félix-Gastélum, Rubén; Maldonado-Mendoza, Ignacio Eduardo; Beltran-Peña, Hugo; Apodaca-Sánchez, Miguel Ángel; Espinoza-Matías, Silvia; Martínez-Valenzuela, María del Carmen; Longoria- Espinoza, Rosa María; Olivas-Peraza, Noel Gerardo Powdery mildews in agricultural crops of Sinaloa: Current status on their identification and future research lines Revista Mexicana de Fitopatología, vol. 35, núm. 1, enero, 2017, pp. 106-129 Sociedad Mexicana de Fitopatología, A.C. Texcoco, México Available in: http://www.redalyc.org/articulo.oa?id=61249777006 How to cite Complete issue Scientific Information System More information about this article Network of Scientific Journals from Latin America, the Caribbean, Spain and Portugal Journal's homepage in redalyc.org Non-profit academic project, developed under the open access initiative Powdery mildews in agricultural crops of Sinaloa: Current status on their identification and future research lines Las cenicillas en cultivos agrícolas de Sinaloa: Situación actual sobre su identificación y líneas futuras de investigación 1Rubén Félix-Gastélum*, 2Ignacio Eduardo Maldonado-Mendoza, 1Hugo Beltran-Peña, 1Miguel Ángel Apodaca-Sánchez, 4Silvia Espinoza-Matías, 1María del Carmen Martínez-Valenzuela, 3Rosa María Lon- goria-Espinoza, 1Noel Gerardo Olivas-Peraza, 1Universidad de Occidente, Unidad Los Mochis, Departamen- to de Ciencias Biológicas, Blvd. Macario Gaxiola y Carretera Internacional s/n, CP 81223. Los Mochis, Sina- loa, México; 2Instituto Politécnico Nacional (IPN), Departamento de Biotecnología Agrícola, CIIDIR-Sinaloa. Blvd. Juan de Dios Bátiz Paredes Nº 250, CP 81101. Guasave, Sinaloa, México; 3Universidad de Occidente, Unidad Guasave, Departamento de Ciencias Biológicas, Av. Universidad s/n, CP 81120.
    [Show full text]
  • Podosphaera Cf. Pruinosa on Rhus Hirta in Germany
    33 Podosphaera cf. pruinosa on Rhus hirta in Germany Herbert Boyle, Uwe Braun, Horst Jage, Volker Kummer & Horst Zimmermann Abstract: Boyle, H., Braun, U., Jage, H., Kummer, V. & Zimmermann, H. 2008: Podosphaera cf. pruinosa on Rhus hirta in Germany. Schlechtendalia 17: 33–38. The introduction of a new powdery mildew disease on Rhus hirta in various parts of Germany (Brandenburg, Rhine-Westphalia, Sachsen-Anhalt and Saxony) is reported. The anamorph found on this host agrees well with the North American Podosphaera pruinosa. Although the teleomorph has not yet been found in Germany and a molecular study has not yet been possible due to the lack of fresh North American material for a comparison, there is little doubt that the European outbreak of the Rhus powdery mildew disease may be referred to as Podosphaera pruinosa. Morphology, taxonomy and distribution of Podosphaera species on Rhus and other hosts of the Anacardiaceae are discussed in detail. Zusammenfassung: Boyle, H., Braun, U., Jage, H., Kummer, V. & Zimmermann, H. 2008: Podosphaera cf. prui-nosa auf Rhus hirta in Deutschland. Schlechtendalia 17: 33–38. Es wird über das Auftreten einer neuen Mehltaukrankheit auf Rhus hirta in verschiedenen Teilen Deutschlands (Brandenburg, Rheinland-Pfalz, Sachsen und Sachsen-Anhalt) berichtet. Die auf diesem Wirt gefundene Anamorphe stimmt gut mit der nordamerikanischen Podosphaera pruinosa überein. Obwohl noch keine Teleomorphe in Deutschland gefunden worden ist und ein molekularer Vergleich mangels der Verfügbarkeit nordamerikanischer Aufsammlungen von Frischmaterial noch nicht möglich war, besteht kaum Zweifel, dass der europäische Ausbruch dieser Rhus-Mehltaukrankheit auf P. pruinosa zurückzuführen ist. Morphologie, Taxonomie und Verbreitung von Podosphaera-Arten auf Rhus und anderen Wirten der Anacardiaceae werden im Detail diskutiert.
    [Show full text]
  • Characterising Plant Pathogen Communities and Their Environmental Drivers at a National Scale
    Lincoln University Digital Thesis Copyright Statement The digital copy of this thesis is protected by the Copyright Act 1994 (New Zealand). This thesis may be consulted by you, provided you comply with the provisions of the Act and the following conditions of use: you will use the copy only for the purposes of research or private study you will recognise the author's right to be identified as the author of the thesis and due acknowledgement will be made to the author where appropriate you will obtain the author's permission before publishing any material from the thesis. Characterising plant pathogen communities and their environmental drivers at a national scale A thesis submitted in partial fulfilment of the requirements for the Degree of Doctor of Philosophy at Lincoln University by Andreas Makiola Lincoln University, New Zealand 2019 General abstract Plant pathogens play a critical role for global food security, conservation of natural ecosystems and future resilience and sustainability of ecosystem services in general. Thus, it is crucial to understand the large-scale processes that shape plant pathogen communities. The recent drop in DNA sequencing costs offers, for the first time, the opportunity to study multiple plant pathogens simultaneously in their naturally occurring environment effectively at large scale. In this thesis, my aims were (1) to employ next-generation sequencing (NGS) based metabarcoding for the detection and identification of plant pathogens at the ecosystem scale in New Zealand, (2) to characterise plant pathogen communities, and (3) to determine the environmental drivers of these communities. First, I investigated the suitability of NGS for the detection, identification and quantification of plant pathogens using rust fungi as a model system.
    [Show full text]
  • I ECOLOGY and EPIDEMIOLOGY of PODOSPHAERA MACULARIS
    ECOLOGY AND EPIDEMIOLOGY OF PODOSPHAERA MACULARIS, THE CAUSAL AGENT OF HOP POWDERY MILDEW A Dissertation Presented to the Faculty of the Graduate School Of Cornell University In Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy by William Weldon August 2020 i © William Weldon ii ECOLOGY AND EPIDEMIOLOGY OF PODOSPHAERA MACULARIS, THE CAUSAL AGENT OF HOP POWDERY MILDEW William Weldon, Ph. D. Cornell University 2020 Over the past twenty years, hop production has expanded in parallel with the craft brewing industry, resulting in a high-value crop with low tolerance for defect in harvested hop cones. Podosphaera macularis is an ascomycete fungus that causes powdery mildew of hop, which is arguably the most destructive disease with respect to its potential for diminishing yield and cone quality. Historically, research on P. macularis has focused largely on the asexual growth forms of the pathogen, as that is the only phase currently observed in the Pacific Northwest (PNW) US region, where over 96% of US hop production resides. As such, the epidemiology and ecology of the disease with respect to the P. macularis ascigerous stage (chasmothecia) is not well understood, even though this growth form has been reported in most hop growing regions east of the Rocky Mountain range. Furthermore, due to the difficult- to-culture obligately biotrophic nature of the pathogen, there are relatively few molecular tools available to track P. macularis population structure and movement. As such, we developed a library of 54 high-throughput, cost effective amplicon sequencing (AmpSeq) molecular markers by re-purposing an existing transcriptome dataset as the source of genetic variation.
    [Show full text]