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Bremia Lactucae) on Lettuce and Side Effects on Basal Rot Caused by Botrytis Cinerea and Rhizoctonia Solani

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Bremia Lactucae) on Lettuce and Side Effects on Basal Rot Caused by Botrytis Cinerea and Rhizoctonia Solani Nathalie Van Hese INTEGRATED CONTROL OF DOWNY MILDEW (BREMIA LACTUCAE) ON LETTUCE AND SIDE EFFECTS ON BASAL ROT CAUSED BY BOTRYTIS CINEREA AND RHIZOCTONIA SOLANI Thesis submitted in fulfilment of the requirements for the degree of Doctor (PhD) in Applied Biological Sciences Dutch translation of the title: Geïntegreerde beheersing van valse meeldauw (Bremia lactucae) in kropsla en neveneffecten op smet, veroorzaakt door Botrytis cinerea en Rhizoctonia solani Cover illustration Bremia lactucae conidium, treated with calcofluor and visualized with a UV epi-fluorescence microscope. Cite as: Van Hese N. (2015) Integrated control of downy mildew (Bremia lactucae) on lettuce and side effects on basal rot caused by Botrytis cinerea and Rhizoctonia solani. PhD thesis, Ghent University, Belgium ISBN-number: 978-90-5989-853-0 The author and promotor give the authorisation to consult and to copy parts of this work for personal use only. Every other use is subject to the copyright laws. Permission to reproduce any material contained in this work should be obtained from the author. Promotor: Prof. Dr. Ir. Monica Höfte Department of Crop Protection, Laboratory of Phytopathology Dean: Prof. Dr. Ir. Marc Van Meirvenne Rector: Prof. Dr. Anne De Paepe Members of the jury Prof. dr. ir. Monica Höfte Department of Crop Protection Ghent University Dr. ir. Peter Bleyaert Tuinbouw onder afdekking – Glasgroenten Inagro Prof. dr. ir. Inge Van Bogaert Department of Biochemical and Microbial Technology Ghent University Prof. dr. ir. Benny De Cauwer Department of Plant Production Ghent University Dr. Marc Ongena Microbial Processes and Interactions (MiPI) Research Unit University of Liège Dr. Berit Nordskog Plant Health and Biotechnology Division Nibio – Norwegian Institute of Bioeconomy Research I Dankwoord Een doctoraatsstudie maken kan een beetje vergeleken worden met een kaartenhuisje bouwen: er is het enthousiasme als de toren weer wat hoger wordt, en de schrik en stress als de constructie wankelt. Verder bestaat een kaartenhuisje uit vele kaarten, en zo zijn er ook bij het maken van een doctoraat veel mensen betrokken. Deze verdienen hier dan ook terecht een bedanking. First, I would like to thank the members of the jury, for their valuable input. Ik wil ook Prof. Van Damme bedanken om het voorzitterschap voor de verdediging op zich te nemen. Dan is er natuurlijk mijn promotor, Monica Höfte. Als zij mij niet de kans gegeven had eerst een thesis te maken aan haar labo, en daarna te starten aan dit project, was er van mijn doctoraatsthesis natuurlijk geen sprake geweest. Monica slaagde erin een geweldige team samen te stellen en het te leiden. Bedankt voor alle kansen, Monica. Dat geweldige team, dat waren mijn fantastische collega’s. Toen het tijd werd na het indienen van mijn doctoraatsthesis, had ik schrik dat ik nergens nog een job zou vinden met zo’n geweldige collega’s. Laat ik beginnen bij de “oude garde”, waar ik veel van leerde, maar die ook stuk voor stuk heel toffe mensen bleken te zijn: Katrien, Jolien, Sarah, Soraya: dank jullie wel om mij wegwijs te maken in het labo. Ellen, van jou nam ik het Bremia project over en jij en jouw notities hebben me geholpen bij de start van mijn project. Evelien, Lien B., Jonas, Jasper: jullie gaven een heel eigen, leuke dynamiek aan het labo. Dank jullie wel. Jonas, jij was trouwens de eerste die me hulp bood bij het aanvragen van mijn IWT-beurs, wat enorm gewaardeerd werd! Feyi, you are a wonderfull, caring, friendly and funny person. Khuong, you make the best springrolls ever and it is always nice talking to you. Vincent we started writing our thesis at the same moment, which gave a connection between us. I hope you are doing well and you can finish soon! You taught me so much, even about Belgian history! ZongWang, silent, but always with a smile and a talented runner. It was nice to have you in our team for the Ekiden run! Nam, you thaught me a lot in the lab and you have the most infectious laugh! Andrea, although you were only one year in our lab, it felt like you belonged here from the first moment! Huangske, you supported me so much, and you even planned your trip to Belgium to come to my wedding. You and your wife are very lovely people! Every lab needs a Huang! Thank you all! Lien T., we kenden elkaar natuurlijk al van tijdens onze studies en het was leuk om samen met jou de EIP cursus te volgen! Nadia, nooit kon ik iets verkeerd vragen aan jou, dank je wel daarvoor! Ook Bjorn, jij bedankt voor alle administratieve hulp. Evelien, jij hebt nog zoveel cupcakes tegoed voor al het werk waarmee je mij geholpen hebt, al die qPCR’s! Zonder jou was dat nooit goed gekomen! Maar daarnaast ben je ook een ongelooflijk toffe aanwinst voor het labo, goedlachs en altijd vrolijk! Ozzy, we hadden soms pittige discussies, maar we hebben veel gelachen en jouw mojito-bolletjes vergeet ik niet! Silketje, jij bent fantastisch: je staat altijd klaar voor mensen: of het nu is om te helpen met labowerk of om een luisterend oor te bieden. Ons citytripje in Zweden was echt leuk en Werchter was trouwens ook geweldig. Ik kijk al uit naar volgend jaar! Crazy Paulinie! Het was geweldig om iemand te hebben in het labo die even gek is als ik én die mijn looppassie deelt. Lieselotte, we zijn samen begonnen aan onze doctoraatsstudie, en hebben onze ups en downs die III daar onvermijdelijk mee gepaard gaan samen beleefd. Ik heb veel steun aan je gehad, maar we hebben toch ook ongelooflijk veel plezier gehad samen! David, onvoorstelbaar dat ik in het begin schrik had van jou. Je hebt vaak tijd vrijgemaakt om mijn resultaten te bespreken en die qPCR die we samen gedaan hebben, was eigenlijk de enige leuke die ik gedaan heb. Maar het is ook altijd heel leuk babbelen en zeveren met jou. En dan had ik nog de meest fantastische bureau die je je kan indenken. Sorenneke, you were always so enthusiastic and full of jokes, a real multipotentialite person. JingJing, since the last year you were in Belgium, we called eachother ‘twinsister’, it tells something about us. It was fantastic to go to China with you and I love that we still mail eachother so frequently, but I hope we will meet again soon! En tot slot is er Ilseke. Het is zo moeilijk om te beschrijven hoe fantastisch jij bent. Een luisterend oor, praktische raad, altijd goedlachs en optimistisch, vol passies… Ik kan met jou over alles, maar dan ook echt alles praten. Dan was er ook nog mijn fantastische studente, Lien: ik ben blij dat ik jouw begeleidster mocht zijn! Voor dit doctoraat werkte ik ook vaak samen met de proefcentra, Inagro, PCG en PSKW. Dat was steeds een prettige samenwerking waar ik ook veel leuke mensen heb ontmoet: Aaike, Isabel, Ilse, Nathalie, Ronny, Roger, An, Sofie, Kenneth, en Ilse: bedankt voor de aangename samenwerking! En dan is er die andere groep die heeft bijgedragen aan mijn kaartenhuisje, de mensen die niets te maken hadden met dit werk, maar wel erg belangrijk zijn voor mij. Sara en Hanna, we kennen elkaar al zo lang, jullie zijn fantastische vriendinnen! Ook Isabel, we hebben samen al heel veel leuke momenten meegemaakt, meer van dat! Iris, Sven, Kaat, Katrien, Ann en Tine, bedankt voor de leuke uitstapjes en steun! Dan kom ik ook bij mijn familie en schoonfamilie, bedankt voor alle getoond interesse, hulp en de leuke momenten! Mijn geweldige ouders, die altijd voor mij klaar staan, ik besef heel goed dat ik veel geluk heb. Zonder jullie liefde en steun zou ik hier nooit geraakt zijn. Dank je wel voor alles! Mijn zusje, mijn beste vriendin, mijn hulplijn, mijn loopmaatje, de beste zus ter wereld, jij ook hartelijk bedankt! En dan mijn Roenie, alle ups en downs komen eerst bij jou terecht! Door alles wat zo’n doctoraat met zich meebrengt, ben ik er nog meer van overtuigd dat jij en ik samen alles aankunnen. <3 IV List of abbreviations AG anastomosis group Avr avirulence Ca calcium CLP cyclic lipopeptides dbi days before inoculation dpi days post inoculation DMSO dimethyl sulfoxide EHM extrahaustorial membrane ET ethylene Eth Ethephon ETI effector triggered immunity ETS effector triggered susceptibility F10 fengycin 10 mg/L HIGS host-induced gene silencing siRNA small interfering ribonucleic acid hpi hours post inoculation IBEB International Bremia Evaluation Board IPM integrated pest management ISR induced systemic resistance JA jasmonic acid LHP lipid hydroperoxidase LOX lipoxygenase M10 mycosubtilin 10 mg/L MAMP microbe associated molecular pattern MeJA methyl-jasmonate MS-medium Murashige and Skoog medium NB-LRR proteins nucleotide-binding leucine rich repeats proteins NHR non host resistance V List of abbreviations NO nitric oxide pal phenylalanine ammonia lyase PAMP pathogen associated molecular pattern PDA potato dextrose agar PDB potato dextrose broth PGPR plant growth-promoting rhizobacteria pr pathogenesis related PRR pattern recognition receptors PTI PAMP-triggered immunity qRT-PCR quantitative reverse transcriptase polymerase chain reaction ROS reactive oxygen species QTL quantitative trait loci S10 surfactin 10 mg/L SA salicylic acid SAR systemic acquired resistance VI Table of contents MEMBERS OF THE JURY..................................................................................................................................... I DANKWOORD ................................................................................................................................................. III LIST OF ABBREVIATIONS ..................................................................................................................................
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