DOCSLIB.ORG

MS Thesis, Washington State University, Department

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
MS Thesis, Washington State University, Department EVALUATION OF SEED AND DRENCH TREATMENTS FOR MANAGEMENT OF DAMPING-OFF AND SEEDLING BLIGHT PATHOGENS OF SPINACH FOR ORGANIC PRODUCTION By JAIME ANNE CUMMINGS A thesis submitted in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE IN PLANT PATHOLOGY WASHINGTON STATE UNIVERSITY Department of Plant Pathology DECEMBER 2007 To the Faculty of Washington State University: The members of the Committee appointed to examine the thesis of JAIME ANNE CUMMINGS find it satisfactory and recommend that it be accepted. ____________________________________ Chair ____________________________________ ____________________________________ ____________________________________ ii ACKNOWLEDGEMENTS Professional I would like to thank my advisor, Dr. Lindsey du Toit, for welcoming me into the Vegetable Seed Pathology Program at WSU Mount Vernon Northwestern Washington Research and Extension Center, and for her patience and enthusiasm in introducing me to the field of Plant Pathology. I am grateful for her advice and guidance. The experiences and skills gained while working with her are immeasurable. I also thank my committee members; Dr. Debra Inglis, Dr. Carol Miles, and Dr. Frank Dugan, for their collective and individual contributions which made this project a success. I would like to extend a special thank you to Dr. Inglis for her time, attention, and guidance; her contributions to the successful completion of this degree are greatly appreciated. I would like to thank the WSU Center for Sustaining Agriculture and Natural Resources Organic Research Program for funding this project and Dr. Miles for her part in securing the funding. Additionally, I would like to thank Dr. Dugan for his time and guidance while I was in Pullman and new to the department. I would like to extend my gratitude to the entire WSU Mount Vernon NWREC faculty and staff for all their assistance and encouragement, and especially to the entire VSP team. Particularly Mike Derie for his expertise, patience, and assistance with many aspects of my project; Louise Brissey for all her expertise and the hours she contributed at the microscope and elsewhere, as well as for her undying encouragement; Barbara Holmes for all of her technical assistance with the greenhouse and field trials, and incredible willingness to do whatever needed to be done; and Kerri Brooks for her efficiency and accuracy with the germination assays and many other contributions, including her spectacular personality which made work fun. I would also like to acknowledge Carl Libbey for all his support and contributions as my ‘go-to-man’ at the station for so many uncountable things. Thank you to Ron Dralle, Dan Gorton, and Juan iii Alonso for all they did to ensure that the facilities and fields were suitable for research, and to the office staff, Pat King, Kathy Gleissner, and Jeanne Burritt for answering all my questions and for processing all my paperwork. Additionally, I would like to thank the ladies in the office in Pullman, Cheryl Hagelganz and Mary Stormo, for all of their assistance. Personal I would like to thank Aaron Jacobsen for his support and encouragement, as well as his selfless tolerance and understanding throughout my time as a student. I would also like to thank my parents, Jim and Judy Cummings for their support and encouragement. I thank Moosie for being a constant and fantastic source of comfort and relaxation. Additionally, I would like to acknowledge and thank Leigh Ann Harrison for all her advice, guidance and support, and for being a terrific friend who always had an open ear. iv EVALUATION OF SEED AND DRENCH TREATMENTS FOR MANAGEMENT OF DAMPING-OFF AND SEEDLING BLIGHT PATHOGENS OF SPINACH FOR ORGANIC PRODUCTION Abstract by Jaime Anne Cummings, M.S. Washington State University December 2007 Chair: Lindsey du Toit There are many concerns regarding losses to seedborne and soilborne pathogens in organic production systems because of limited effective options available for disease management that satisfy organic standards. Seed treatments can be inexpensive and effective, including those with biological control agents (BCAs). However, the reliability of BCAs for disease control is affected by crop species, whether a pathogen is seedborne or soilborne, and numerous abiotic factors. The efficacy of a range of seed and drench treatments for control of soilborne seedling blight and damping-off pathogens was investigated using spinach as a model small-seeded vegetable. The seed and drench treatments included those that were EPA registered and approved for use in organic agriculture as defined by the National Organic Standards, and those that were being developed for registration and compliance with organic standards. Greenhouse inoculation rate trials were completed for each of three soilborne pathogens, Fusarium oxysporum f. sp. spinaciae, Pythium ultimum, and Rhizoctonia solani. Results were then used to evaluate 14 seed and drench treatments in greenhouse trials against each pathogen. For P. ultimum, two experimental seed treatments, Experimental #1 and #2, provided equivalent control to that provided by a conventional fungicide seed treatment, Apron XL LS; while Natural II, Natural X, and Subtilex seed treatments each suppressed damping-off significantly in only one of v two trials. For F. oxysporum f. sp. spinaciae, drenches with a compost tea or Prestop, and seed treatment with Yield Shield suppressed post-emergence wilt significantly in one of two trials; but no treatment was highly effective. For R. solani, Experimental #1 and Natural II seed treatments reduced damping-off as effectively as a drench with the conventional fungicide Terraclor. Seed health assays revealed that treatments with Experimental #1, Experimental #2, or Mycostop Mix significantly reduced the incidence of seedborne Verticillium and Alternaria. Natural II and Natural X seed treatments significantly reduced early germination in seed germination assays. Selected treatments were evaluated further under field conditions at three locations in western Washington. There was little consistency in results among field trials. However, Experimental #1 and #2 seed treatments consistently caused significantly earlier emergence than the other treatments. In contrast, the compost tea drench resulted in low total emergence and low spinach biomass, but also low post-emergence wilt in two of three trials. vi TABLE OF CONTENTS Page ACKNOWLEDGMENTS ............................................................................................................. iii ABSTRACT.....................................................................................................................................v LIST OF TABLES......................................................................................................................... ix LIST OF FIGURES .........................................................................................................................x CHAPTER 1. Literature Review 1.1. Soilborne fungal plant pathogens..................................................................................1 1.2. Biological control of soilborne plant pathogens ...........................................................4 1.3. Seed pathology and seed treatments .............................................................................6 1.4. Organic production .....................................................................................................10 1.5. Spinach 1.5.1. Spinach and spinach seed production ..........................................................13 1.5.2. Diseases affecting spinach and spinach seed production.............................15 1.6. Fusarium wilts 1.6.1. Background and importance ........................................................................17 1.6.2. Fusarium oxysporum ...................................................................................17 1.6.3. Management of Fusarium wilts ...................................................................18 1.7. Pythium species as plant pathogens 1.7.1. Background and importance ........................................................................22 1.7.2. Pythium ultimum ..........................................................................................23 1.7.3. Management of Pythium damping-off.........................................................23 1.8. Rhizoctonia species as plant pathogens 1.8.1. Background and importance ........................................................................25 1.8.2. Rhizoctonia solani........................................................................................26 1.8.3. Management of Rhizoctonia damping-off and seedling blight....................27 1.9. Conclusion and research needs ...................................................................................29 1.10. Literature cited..........................................................................................................31 2. Greenhouse pathogen inoculation rate trials, and seed and drench treatment trials for organic production 2.1. INTRODUCTION......................................................................................................42 2.2. MATERIALS AND METHODS 2.2.1. Pathogen isolates..........................................................................................45 2.2.2. Preparation of inocula..................................................................................48 2.2.3. Inoculation of potting mix for greenhouse inoculation
Load more

Recommended publications
  • Old Woman Creek National Estuarine Research Reserve Management Plan 2011-2016
    Old Woman Creek National Estuarine Research Reserve Management Plan 2011-2016 April 1981 Revised, May 1982 2nd revision, April 1983 3rd revision, December 1999 4th revision, May 2011 Prepared for U.S. Department of Commerce Ohio Department of Natural Resources National Oceanic and Atmospheric Administration Division of Wildlife Office of Ocean and Coastal Resource Management 2045 Morse Road, Bldg. G Estuarine Reserves Division Columbus, Ohio 1305 East West Highway 43229-6693 Silver Spring, MD 20910 This management plan has been developed in accordance with NOAA regulations, including all provisions for public involvement. It is consistent with the congressional intent of Section 315 of the Coastal Zone Management Act of 1972, as amended, and the provisions of the Ohio Coastal Management Program. OWC NERR Management Plan, 2011 - 2016 Acknowledgements This management plan was prepared by the staff and Advisory Council of the Old Woman Creek National Estuarine Research Reserve (OWC NERR), in collaboration with the Ohio Department of Natural Resources-Division of Wildlife. Participants in the planning process included: Manager, Frank Lopez; Research Coordinator, Dr. David Klarer; Coastal Training Program Coordinator, Heather Elmer; Education Coordinator, Ann Keefe; Education Specialist Phoebe Van Zoest; and Office Assistant, Gloria Pasterak. Other Reserve staff including Dick Boyer and Marje Bernhardt contributed their expertise to numerous planning meetings. The Reserve is grateful for the input and recommendations provided by members of the Old Woman Creek NERR Advisory Council. The Reserve is appreciative of the review, guidance, and council of Division of Wildlife Executive Administrator Dave Scott and the mapping expertise of Keith Lott and the late Steve Barry.
    [Show full text]
  • Pythium Ultimum Species Complex
    Resolving thePythium ultimum species complex by Quinn Eggertson A thesis submitted to the Faculty of Graduate and Postdoctoral Affairs partial fulfillment of the requirements for the degree of Master of Science in Biology Carleton University Ottawa, Ontario ©2012 Quinn Eggertson Library and Archives Bibliotheque et Canada Archives Canada Published Heritage Direction du 1+1 Branch Patrimoine de I'edition 395 Wellington Street 395, rue Wellington Ottawa ON K1A0N4 Ottawa ON K1A 0N4 Canada Canada Your file Votre reference ISBN: 978-0-494-93569-9 Our file Notre reference ISBN: 978-0-494-93569-9 NOTICE: AVIS: The author has granted a non­ L'auteur a accorde une licence non exclusive exclusive license allowing Library and permettant a la Bibliotheque et Archives Archives Canada to reproduce, Canada de reproduire, publier, archiver, publish, archive, preserve, conserve, sauvegarder, conserver, transmettre au public communicate to the public by par telecommunication ou par I'lnternet, preter, telecommunication or on the Internet, distribuer et vendre des theses partout dans le loan, distrbute and sell theses monde, a des fins commerciales ou autres, sur worldwide, for commercial or non­ support microforme, papier, electronique et/ou commercial purposes, in microform, autres formats. paper, electronic and/or any other formats. The author retains copyright L'auteur conserve la propriete du droit d'auteur ownership and moral rights in this et des droits moraux qui protege cette these. Ni thesis. Neither the thesis nor la these ni des extraits substantiels de celle-ci substantial extracts from it may be ne doivent etre imprimes ou autrement printed or otherwise reproduced reproduits sans son autorisation.
    [Show full text]
  • Enhancement of Development and Induction of Resistance in Tomato
    Enhancement of development and induction of resistance in tomato plants by the antagonist, Pythium oligandrum Gaétan Le Floch, Patrice Rey, Franck Déniel, Nicole Benhamou, Karine Picard, Yves Tirilly To cite this version: Gaétan Le Floch, Patrice Rey, Franck Déniel, Nicole Benhamou, Karine Picard, et al.. Enhancement of development and induction of resistance in tomato plants by the antagonist, Pythium oligandrum. Agronomie, EDP Sciences, 2003, 23 (5-6), pp.455-460. 10.1051/agro:2003018. hal-00886197 HAL Id: hal-00886197 https://hal.archives-ouvertes.fr/hal-00886197 Submitted on 1 Jan 2003 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Agronomie 23 (2003) 455–460 455 © INRA, EDP Sciences, 2003 DOI: 10.1051/agro:2003018 Original article Enhancement of development and induction of resistance in tomato plants by the antagonist, Pythium oligandrum Gaétan LE FLOCHa, Patrice REYa*, Franck DÉNIELa, Nicole BENHAMOUb, Karine PICARDa, Yves TIRILLYa a Laboratoire de Microbiologie, Université de Bretagne Occidentale-Brest, Technopôle Brest-Iroise, 29280 Plouzané, France b Département Recherche en Sciences de la Vie et de la Santé, Pav. Ch.E. Marchand, Université Laval, Sainte-Foy, Québec, GIK7P4, Canada (Received 3 July 2002; accepted 18 December 2002) Abstract – To exert an optimal biological control, P.
    [Show full text]
  • The Genus Pythium in Mainland China
    菌物学报 [email protected] 8 April 2013, 32（增刊）: 20-44 Http://journals.im.ac.cn Mycosystema ISSN1672-6472 CN11-5180/Q © 2013 IMCAS, all rights reserved. The genus Pythium in mainland China HO Hon-Hing* Department of Biology, State University of New York, New Paltz, New York 12561, USA Abstract: A historical review of studies on the genus Pythium in mainland China was conducted, covering the occurrence, distribution, taxonomy, pathogenicity, plant disease control and its utilization. To date, 64 species of Pythium have been reported and 13 were described as new to the world: P. acrogynum, P. amasculinum, P. b ai sen se , P. boreale, P. breve, P. connatum, P. falciforme, P. guiyangense, P. guangxiense, P. hypoandrum, P. kummingense, P. nanningense and P. sinensis. The dominant species is P. aphanidermatum causing serious damping off and rotting of roots, stems, leaves and fruits of a wide variety of plants throughout the country. Most of the Pythium species are pathogenic with 44 species parasitic on plants, one on the red alga, Porphyra: P. porphyrae, two on mosquito larvae: P. carolinianum and P. guiyangense and two mycoparasitic: P. nunn and P. oligandrum. In comparison, 48 and 28 species have been reported, respectively, from Taiwan and Hainan Island with one new species described in Taiwan: P. sukuiense. The prospect of future study on the genus Pythium in mainland China was discussed. Key words: Pythiaceae, taxonomy, Oomycetes, Chromista, Straminopila 中国大陆的腐霉属菌物 何汉兴* 美国纽约州立大学 纽约 新帕尔茨 12561 摘 要：综述了中国大陆腐霉属的研究进展，内容包括腐霉属菌物的发生、分布、分类鉴定、致病性、所致植物病 害防治及腐霉的利用等方面。至今，中国已报道的腐霉属菌物有 64 个种，其中有 13 个种作为世界新种进行了描述， 这 13 个新种分别为：顶生腐霉 Pythium acrogynum，孤雌腐霉 P.
    [Show full text]
  • The Taxonomy and Biology of Phytophthora and Pythium
    Journal of Bacteriology & Mycology: Open Access Review Article Open Access The taxonomy and biology of Phytophthora and Pythium Abstract Volume 6 Issue 1 - 2018 The genera Phytophthora and Pythium include many economically important species Hon H Ho which have been placed in Kingdom Chromista or Kingdom Straminipila, distinct from Department of Biology, State University of New York, USA Kingdom Fungi. Their taxonomic problems, basic biology and economic importance have been reviewed. Morphologically, both genera are very similar in having coenocytic, hyaline Correspondence: Hon H Ho, Professor of Biology, State and freely branching mycelia, oogonia with usually single oospores but the definitive University of New York, New Paltz, NY 12561, USA, differentiation between them lies in the mode of zoospore differentiation and discharge. Email [email protected] In Phytophthora, the zoospores are differentiated within the sporangium proper and when mature, released in an evanescent vesicle at the sporangial apex, whereas in Pythium, the Received: January 23, 2018 | Published: February 12, 2018 protoplast of a sporangium is transferred usually through an exit tube to a thin vesicle outside the sporangium where zoospores are differentiated and released upon the rupture of the vesicle. Many species of Phytophthora are destructive pathogens of especially dicotyledonous woody trees, shrubs and herbaceous plants whereas Pythium species attacked primarily monocotyledonous herbaceous plants, whereas some cause diseases in fishes, red algae and mammals including humans. However, several mycoparasitic and entomopathogenic species of Pythium have been utilized respectively, to successfully control other plant pathogenic fungi and harmful insects including mosquitoes while the others utilized to produce valuable chemicals for pharmacy and food industry.
    [Show full text]
  • Beneficial Effects of the Oomycete Pythium Oligandrum on Grapevines - Jonathan Gerbore - University of Pau Et Des Pays De L’Adour
    Short Communication Journal of Applied Microbiology and Biochemistry 2020 Vol.4 No.4 Applied Microbiology 2016- Microorganisms to protect plants: Beneficial effects of the oomycete Pythium oligandrum on grapevines - Jonathan Gerbore - University of Pau et des Pays de l’Adour Jonathan Gerbore University of Pau et des Pays de l’Adour, France Abstract Development of alternative methods to chemical pesticides to In soilless cultures, the recycling of drainage water within a control plant diseases increased considerably in recent years. system is that the consequence of latest laws concerning water Among those, the useful and beneficial microorganisms for saving and limitation of pollution. Such closed systems plant growth stimulation and plant protection is promising, minimize costs by conserving water and reducing fertilizer especially under recent advances in trancriptomics and genome input; however, they'll favor the dissemination of pathogens. sequencing that provides new insights in the potential of When pathogens manage to enter recirculation systems, they're microorganisms and new product development opportunities. rapidly disseminated and will cause disease epidemics, Our report of development of a biocontrol product base on the particularly during times of stress, e.g., stress because of high oomycete, Pythium oligandrum, to protect grape. Oligandrum temperatures and/or to low levels of dissolved oxygen within ine against Escape, a serious grapevine trunk disease that the nutrient solution. Thus, numerous facultative pathogens causes substantial losses in vineyards worldwide. There are No commonly found in conventional cultures may become efficient chemical products are registered against this disease. economically significant (53). Several of them, e.g., Pythium In order to control Esca, P.
    [Show full text]
  • Two Species of Phytopythium (Pythiaceae, Pythiales) New to China
    Journal of Microbiology & Experimentation Research Article Open Access Two species of Phytopythium (Pythiaceae, Pythiales) new to China Abstract Volume 7 Issue 5 - 2019 Two oomycetes, Phytopythium mercuriale and Pp. sindhum were found in southern China, Jia-Jia Chen,1,2 Hui Feng,1 Xiaobo Zheng1 and they are newly recorded in China. These two species were both isolated from roots of 1Department of Plant Pathology, Nanjing Agricultural University, soybean. Pp. mercuriale is characterized by subglobose sporangia with conspicuous apical China papillae, and occasionally forming oogonia. And Pp. sindhum is identified from other 2College of Landscape Architecture, Jiangsu Vocational College Phytopythium species by its globose to sub-globose sporangia with conspicuous apical of Agriculture and Forestry, China papillae, large and smooth oogonia, monoclinous or diclinous antheridia, and plerotic or nearly plerotic and thick-walled oospores. Illustrations and descriptions of the two new Correspondence: Xiaobo Zheng, Department of Plant records are provided based on the materials from China. Pathology, Nanjing Agricultural University, Nanjing 210095, China, Tel 18362090654, Email Keywords: Cox1, ITS, Oomycota, Phytopythium mercuriale, Phytopythium sindhum Received: August 09, 2019 | Published: September 16, 2019 Abbreviations: BI, bayesian inference; BPP, bayesian posterior in China. The isolation procedure followed the method described by probabilities; BT, bootstrap; CMA, corn meal agar; CI, consistency Benard & Punja.11 Pieces of tissue 5–10mm were cut from the roots, index; Cox1, cytochrome c oxidase subunit 1; GTR, general time washed in tap water and superficially dried on a paper towel, and plated reversible; HI, homoplasy index; ITS, the internal transcribed spacer; on CMA containing rifampicin (50mg/L), phenamacril (5mg/L), MP, maximum parsimony; MPT, maximum parsimonious tree; NJAU, ampicillin (50mg/L), and pentachloronitrobenzene (50mg/L) and the College of Plant Protection, Nanjing Agricultural University; incubated at 25°C for 2–3d.
    [Show full text]
  • Abbreviations
    Abbreviations AfDD Acriflavine direct detection AODC Acridine orange direct count ARA Arachidonic acid BPE Bleach plant effluent Bya Billion years ago CFU Colony forming unit DGGE Denaturing gradient gel electrophoresis DHA Docosahexaenoic acid DOC Dissolved organic carbon DOM Dissolved organic matter DSE Dark septate endophyte EN Ectoplasmic net EPA Eicosapentaenoic acid FITC Fluorescein isothiocyanate GPP Gross primary production ITS Internal transcribed spacer LDE Lignin-degrading enzyme LSU Large subunit MAA Mycosporine-like amino acid MBSF Metres below surface Mpa Megapascal MPN Most probable number MSW Molasses spent wash MUFA Monounsaturated fatty acid Mya Million years ago NPP Net primary production OMZ Oxygen minimum zone OUT Operational taxonomic unit PAH Polyaromatic hydrocarbon PCR Polymerase chain reaction © Springer International Publishing AG 2017 345 S. Raghukumar, Fungi in Coastal and Oceanic Marine Ecosystems, DOI 10.1007/978-3-319-54304-8 346 Abbreviations POC Particulate organic carbon POM Particulate organic matter PP Primary production Ppt Parts per thousand PUFA Polyunsaturated fatty acid QPX Quahog parasite unknown SAR Stramenopile Alveolate Rhizaria SFA Saturated fatty acid SSU Small subunit TEPS Transparent Extracellular Polysaccharides References Abdel-Waheb MA, El-Sharouny HM (2002) Ecology of subtropical mangrove fungi with empha- sis on Kandelia candel mycota. In: Kevin D (ed) Fungi in marine environments. Fungal Diversity Press, Hong Kong, pp 247–265 Abe F, Miura T, Nagahama T (2001) Isolation of highly copper-tolerant yeast, Cryptococcus sp., from the Japan Trench and the induction of superoxide dismutase activity by Cu2+. Biotechnol Lett 23:2027–2034 Abe F, Minegishi H, Miura T, Nagahama T, Usami R, Horikoshi K (2006) Characterization of cold- and high-pressure-active polygalacturonases from a deep-sea yeast, Cryptococcus liquefaciens strain N6.
    [Show full text]
  • Biological Control Methods for Damping-Off of Tomato Seedlings Caused by Pythium Myriotylum
    University of Tennessee, Knoxville TRACE: Tennessee Research and Creative Exchange Masters Theses Graduate School 5-2006 Biological Control Methods for Damping-off of Tomato Seedlings Caused by Pythium myriotylum Miranda Marshall Clark University of Tennessee - Knoxville Follow this and additional works at: https://trace.tennessee.edu/utk_gradthes Part of the Entomology Commons Recommended Citation Clark, Miranda Marshall, "Biological Control Methods for Damping-off of Tomato Seedlings Caused by Pythium myriotylum. " Master's Thesis, University of Tennessee, 2006. https://trace.tennessee.edu/utk_gradthes/1527 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 Miranda Marshall Clark entitled "Biological Control Methods for Damping-off of Tomato Seedlings Caused by Pythium myriotylum." 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 Entomology and Plant Pathology. Kimberly D. Gwinn, Major Professor We have read this thesis and recommend its acceptance: Bonnie H. Ownley, Ernest C. Bernard, Craig H. Canaday Accepted for the Council: Carolyn R. Hodges
    [Show full text]
  • Evaluation of Downy Mildew (Peronospora Farinosa F.Sp
    Brigham Young University BYU ScholarsArchive Theses and Dissertations 2008-07-15 Evaluation of Downy Mildew (Peronospora farinosa f.sp. chenopodii) Resistance among Quinoa Genotypes and Investigation of P. farinosa Growth using Scanning Electron Microscopy Leilani Kitz Brigham Young University - Provo Follow this and additional works at: https://scholarsarchive.byu.edu/etd Part of the Animal Sciences Commons BYU ScholarsArchive Citation Kitz, Leilani, "Evaluation of Downy Mildew (Peronospora farinosa f.sp. chenopodii) Resistance among Quinoa Genotypes and Investigation of P. farinosa Growth using Scanning Electron Microscopy" (2008). Theses and Dissertations. 1512. https://scholarsarchive.byu.edu/etd/1512 This Thesis is brought to you for free and open access by BYU ScholarsArchive. It has been accepted for inclusion in Theses and Dissertations by an authorized administrator of BYU ScholarsArchive. For more information, please contact [email protected], [email protected]. EVALUATION OF DOWNY MILDEW (PERONOSPORA FARINOSA F.SP. CHENOPODII) RESISTANCE AMONG QUINOA GENOTYPES AND INVESTIGATION OF P. FARINOSA GROWTH USING SCANNING ELECTRON MICROSCOPY by Leilani Kitz A thesis submitted to the faculty of Brigham Young University in partial fulfillment of the requirements for the degree of Master of Science Department of Plant and Wildlife Sciences Brigham Young University August 2008 BRIGHAM YOUNG UNIVERSITY GRADUATE COMMITTEE APPROVAL of a thesis submitted by Leilani Kitz This thesis has been read by each member of the following
    [Show full text]
  • Aphanomyces Euteiches Laurent Camborde
    Fuctional characterization of different candidate effectors from the root rot oomycete Aphanomyces euteiches Laurent Camborde To cite this version: Laurent Camborde. Fuctional characterization of different candidate effectors from the root rot oomycete Aphanomyces euteiches. Vegetal Biology. Université Paul Sabatier - Toulouse III, 2020. English. NNT : 2020TOU30227. tel-03208760 HAL Id: tel-03208760 https://tel.archives-ouvertes.fr/tel-03208760 Submitted on 26 Apr 2021 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Abstract Oomycetes are eukaryote pathogens able to infect plants and animals. During host interaction, oomycetes secrete various molecules, named effectors, to counteract plant defence and modulate plant immunity. Two different classes of cytoplasmic effectors have been described to date, Crinklers (CRNs) and RxLR proteins. The translocation process allowing the entrance into the host cells is still unclear, and while extended research gave insight into some molecular targets and role during infection, most of effectors have not been characterized. In the root rot pathogen of legumes Aphanomyces euteiches, only the CRNs are present. Based on a previous study reported by our research group, we published an opinion paper focused on the emergence of DNA damaging effectors and their role during infection.
    [Show full text]
  • Sensitivity of Rhizoctonia Solani and Aphanomyces Cochlioides To
    SENSITIVITY OF RHIZOCTONIA SOLANI AND APHANOMYCES COCHLIOIDES TO FUNGICIDES, AND FITNESS OF TETRACONAZOLE-RESISTANT ISOLATES OF CERCOSPORA BETICOLA AFTER EXPOSURE TO DIFFERENT TEMPERATURE REGIMES A Dissertation Submitted to the Graduate Faculty Of the North Dakota State University of Agriculture and Applied Sciences By Sahar Ibrahim Arabiat In Partial Fulfillment of the Requirements For the Degree of DOCTOR OF PHILOSOPHY Major Department: Plant Pathology November 2014 Fargo, North Dakota North Dakota State University Graduate School Title SENSITIVITY OF RHIZOCTONIA SOLANI AND APHANOMYCES COCHLIOIDES TO FUNGICIDES, AND FITNESS OF TETRACONAZOLE-RESISTANT ISOLATES OF CERCOSPORA BETICOLA AFTER EXPOSURE TO DIFFERENT TEMPERATURE REGIMES By Sahar Ibrahim Arabiat The Supervisory Committee certifies that this disquisition complies with North Dakota State University’s regulations and meets the accepted standards for the degree of DOCTOR OF PHILOSOPHY SUPERVISORY COMMITTEE: Mohamed Khan Chair Gary Secor Melvin Bolton Marisol Berti Approved: December 4, 2015 Jack Rasmussen Date Department Chair ABSTRACT North Dakota and Minnesota produce 55% of USA sugarbeet production. Diseases caused by Rhizoctonia solani, Aphanomyces cochlioides, and Cercospora beticola are the major diseases affecting sugarbeet production in North Dakota and Minnesota. Growers mainly use partial resistant varieties and fungicides to manage diseases of sugarbeet. Sensitivity of R. solani and A. cochlioides to fungicides were evaluated in vitro using mycelium radial growth assay and by evaluating disease severity on inoculated plants treated with fungicides in the greenhouse. Phenotypic stability of tetraconazole-resistant isolates of C. beticola after exposure to different temperature regimes was evaluated. For R. solani, mean EC50 values for baseline isolates were 49.7, 97.1, 0.3, 0.2, and 0.9 µg ml-1 and for non-baseline isolates were 296.1, 341.7, 0.9, 0.2, and 0.6 µg ml-1 for azoxystrobin, trifloxystrobin, pyraclostrobin, penthiopyrad, and prothioconazole, respectively.
    [Show full text]