Partial Resistance of Tomatoes Against Phytophthora Infestans, the Late Blight Fungus

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Partial Resistance of Tomatoes Against Phytophthora Infestans, the Late Blight Fungus Partial resistance of tomatoes against Phytophthora infestans, the late blight fungus L. J. Turkenste L.J. Turkensteen Partial resistance oftomatoe s against Phytophthora infestans, the late blight fungus Proefschrift terverkrijgin g vand egraa dva n doctori nd elandbouwwetenschappe n opgeza gva nd eRecto rMagnificus ,dr.ir .H.A . Leniger hoogleraari nd elevensmiddelentechnologie , inhe t openbaart everdedige n opvrijda g9 novembe r 1973de snamiddag st evie ruu r ind eaul ava nd eLandbouwhogeschoo lt eWageninge n Centre for Agricultural Publishing and Documentation Wageningen - 1973 Stellingen 1 Het onderscheid tussen fysiospecifieke resistentie (overgevoeligheidsresis- tentie) en andere typen van resistentie dient bij afwezigheid van kompatibele waard-pathogeenrelaties niet gemaakt te worden aan de hand van fenomenolo- gische, maar op grond van biochemische criteria. 2 Alsi naanmerkin gword tgenomen ,da td eveiligheidstermij nvoo rd etoepassin g vanhe tcarbamaa t 'Zineb'o pandijvi e6 weken ,o psla ,spinazi ee nradij s 4weke ne no ptomate nslecht s3 dage nis ,da ndien td econsumpti eva ngrot e hoeveelhedentomate nontrade nt eworden . Gidsvoo rziekten -e nonkruidbestrijdin gi nland -e ntuinbouw ,1973 : 174-175. 3 Hetpathotyp e2,4-p/1- tva n Phytophthora infestans, dati n197 0gevonde n werdo ptomaa ti nee nproefvel dme taardappel se ntomaten ,waari nd epatho - typen1,2,3-p ,1,3,4- pe n1,4,10- pware ngexntroduceerd ,i sontstaa nui tee n heterokaryonva ntwe eva nd edri egeintroduceerd epathotypen . Ditproefschrift . 4 Dewaargenome nvariati etusse nmonozoosporeculture sgemaak tva nee nmono - zoospore-uitgangscultureva nPhytophthora infestans (Caten,1969 )behoef t nietuitsluiten do pcytoplasmatisch efactore nt eberusten ,aangezie n P. in­ festans eendiploi dvegetatie fmyceliu mbezi t (Sansome& Brasier ,1973 )e n dientengevolgezoospore nnie tvri jzij nva ngenetisch evariabiliteit . C.E.Caten ,1969 .Spontaneou svariabilit yo fsingl eisolate so f Phytophthora infestans. Can.J .Bot. ,48 : 897-905. E.Sansom e& CM .Brasier ,1973 .Diploid yan dchromosoma l structuralhybridit y in Phytophthora infestans. Nature,Lond .241 : 344-345. 5 De veelgehoorde mening, dat het niveau van partiele resistentie in landrassen voldoende hoog zou zijn, is ongegrond, omdat dit niveau mede bepaald wordt door de selectiedruk uitgeoefend door het pathogeen. 6 De vrees, dat de oprichting van grote internationale landbouwkundige insti- tuten, zoals CIMMYT, AVRDCe n CIP, de beoefening van de plantenziektenkunde in de ontwikkelingslanden nadelig zal beinvloeden (Buddenhagen, 1973), is ongegrond. I.W.Buddenhagen , 1973.Th e international research institutes in relation to future development of tropical plant pathology. Second International Congress ofPlan t Pathology -Minneapolis ,Minnesot a - September 5-12, 1973. Abstract ofpapers :N o 0805. 7 Tervermijdin gva nafwijkinge nbi jaardappel -e ntomateplante ni nkasse ne n fytotrons,zoal swaargenome ntijden speriode nme twindsti lwee ri nd ewinter - halfjaren 1971/1972e n1972/1973 ,diene nkweekruimte nvoorzie nt eworde nva n ethyleenfilters. 8 Adaptatie van Phytophthora infestans aan andere gewassen dan gekweekte aard- appeld en tomaten is een mogelijkheid die niet uitgesloten kan worden. 9 In die gebieden van Europa waar 's zomers tomaten buiten worden geteeld, is de invoering van de jaarrondteelt van tomaten de voomaamste oorzaak van de toename van de frequentie en hevigheid waarmee de epidemieen van Phytophthora •infestans bij tomaten optreden. Dit proefschrift. 10 De conclusie van Gallegly (1964), dat de partiele resistentie van de tomate- lijn W.Va 700 tegen 1-t-pathotypen van Phytophthora infestans polygeen be­ paald is, is onjuist; de bevinding dat partiele resistentie kwantitatief vererft, mag niet zonder meer tot een dergelijke conclusie leiden. Dit proefschrift. 11 Bijd eintroducti eva nnieuw etomatecultivar sdi eresisten t zijntege n Cladosporium fulvum, dientd etele rrekenin gt ehoude nme tee ntoenam e vand ekan so paantastin gva ndez ecultivar sdoo r Phytophthora infestans . 12 Inverban dme td esymmetri ei nd eterminologi eva nRobinso n (1969)word t voorgesteldd eter mpathotyp et evervange ndoo rhospideme . R.A.Robinson ,1969 .Diseas eresistanc e terminology.Rev .appl .Mycol. , 48:593-605 . 13 Deintroducti evan ,e nhe twerke nme the tparingstyp eA 2va n Phytophthora infestans inEurop ai sonverantwoordelijk . E. Sansome& CM . Brasier,1973 .Diploid y andchromosoma lstructura l hybridityi n Phytophthora infestans. Nature,Lond .241 :344-345 . 14 Derecent eintroducti eva nhe tparingstyp eA 2 vanPhytophthora infestans inEurop ageef taanleidin gto tbezinnin go pd ebestri jdingsmethode ntege nd e "aardappelziekte"o paardappe le ntomaat ,di ti nverban dme td et everwachte n veranderingeni nd eepidemiologi c (overblijvenva nd eschimme li nd egrond ) end epathogenitei t (versnelde recombinatieva npathogeniteitsfactoren ) vand eschimmel . Proefschriftva nL.J .Turkenstee n Wageningen,9 novembe r197 3 Abstract Turkensteen,L.J . (1973)Partia lresistanc eo ftomatoe sagains t Phytophthora infestans, thelat ebligh tfungus .Doctora lthesis ,Wageningen .ISB N9 022 0 04988 ,(xv )+ 8 8p. ,2 3tbs ,1 5figs , 103refs ,Eng .an dDutc hsummaries . Also:Agric .Res .Rep .(Versl .landbouwk .Onderz. )81 0an dMeded .Inst . Phytopath.Res. ,Wageninge n633 . Inth eNetherlands ,th esourc eo finoculu mo fth elat ebligh t funguso n tomatoes isth elat ebligh t funguso npotat ocrops .I nregion so fEurop e mentioned,wher etomatoe sar egrow ni nth eopen ,P . infestans ontomatoe si s themai nsourc eo finoculum .Especiall yi nBulgari aan dHungary ,th eeffec t ofyear-roun d croppingo ftomatoe so nprevalenc ean d severityo fth ediseas e isobvious . Infiel dan dlaborator yexperiments ,th epathogenicit yt otomatoe so f P. infestans originating frompotatoe s canb eincrease db yseria lpassage s throughtomat ofoliage .I nEurope ,n oothe rhost stha npotatoe s andtomatoe s playeda rol ei nth etomat olat ebligh tepidemidogy . Phacelia tanaoetifolia isadde dt oth ehos t listo fth efungus .Fo rth epurpos eo fgenetic a classification,tw olaborator ymethods ,probi t- lo gdosag eanalysi san d componentsanalysis ,an don efiel dmetho dhav ebee ndevelope d toasses sth e resistanceo ftomatoe sagains tP . infestans. Inparticula rth ecomponent s infectionratio ,lesio nextensio nan d sporulationintensit ywer estudied .I nth efiel dmethod ,th e'apparen t infectionrate 'r wa sused .Fo rbreedin gpurposes ,a simplifie d fieldmetho d wasindicated .A compariso no fth ethre emethod swa smade . Theresistanc eo ftomatoe s increasedconsiderabl yunti la tleas t8 week s afterseeding .Partia lresistanc eo fW.V a70 0agains tth e 1-t-pathotypeo f P. infestans isbase do na singl egene ,her ename dPti2 . Voorwoord Mijnoprecht e dank gaatui tnaa r aliendi eo penigerle iwijz ehebbe nmee - gewerktbi jhe tto t standkome nva ndi tproefschrift . Inhe tbijzonde rwi li kmeldin gmake nva nd evel ewaardevoll e suggesties vanmij npromotor ,dr .J.C .Zadoks . Het onderzoek isverrich t aanhe t Instituutvoo r Plantenziektenkundig Qnderzoek (IPO)t eWageningen .D e gelegenheid diemij daargebode nwer d in ditwer kmij neige hwe g tegaan ,i sdoo rmi j zeergewaardeerd .He tLaborato - riumvoo rFytopathologi e vand e Landbouwhogeschool stelderuimt ebeschikbaa r ind eklimaatkamers .Beid e instellingenwi l ikgaarn emij nerkentelijkhei d betuigenvoo rhu nmedewerking . Vand emedewerker sva nhe t IPOwi li k inhe tbijzonde rnoeme ndr .J.C . Mooie nd ehee rD .Looyen ,di emij deaardappelziekt e leerdenkenne ne nme t wie iko pplezierig e wijzemoch t samenwerken.D ehee rC.F .Scheffe lbe ni k zeerdankbaa rvoo rhe tmake nva nd etekeninge ne nmevrou w0 .Krechting - Janssenvoo rhe t typewerk. Eenreissubsidi e vanhe t Landbouwhogeschoolfondsmaakt ehe tm emogelij k omd eprobleme nbetreffend ed e aardappelziektebij tomaati nenkel e Europese landenva nnabi j te lerenkennen ,wa the tonderzoe k zeer tengoed e isgekomen . Dehee rW .Hoogkame rverleend emi j zijntechnisch ebijstand ,di ei k zeer opprij she b gesteld. Tenslott ebedan k ikmij nvrou we nmij nschoonvade rvoo rhu n onbaatzuch- tigesteu ne nvoo rhe ti nmi j gesteldevertrouwen . Curriculum vitae Deauteu rwer do p4 Septembe r 1936t eNijmege ngeboren .Hi j volgdeee nMULO - opleidingt eArnhe me ndoorlie pd eLandbouwwinterschoo lt eZutphen .N azij n militairedienstplicht ,volgd ehi jd ebeid ehoogst eklasse nva nd eLorentz - HBSt eArnhem .Hi jstudeerd evana f196 0aa nd eLandbouwhogeschoo lt e Wageningene nverkree gi n197 1he tdiplom ava nlandbouwkundi gingenieur .Van ­ afme i 1970werkt ed eauteu ral spromotie-assisten tbi jhe tInstituu tvoo r PlantenziektenkundigOnderzoe kt eWageninge nte rvoorbereidin gva nzij nproef - schrift. Samenvatting Hoofdstuk 7 Ind ejare n 1965to te nme t 1968kwa mP . infestans, deverwekke r vand eaardappelziekte ,i nNederlan depidemisc hvoo ro ptomate ni nkoud ee n lichtgestookt ekassen .Voo rdez etij dwa sd eziekt ei nkastomate nbetrekke - lijkonbekend .He tonverwacht e optredenva ndez e ziektewer dbehalv edoo rd e vooraardappelziekt egunstig eklimatologisch eomstandighede ni ndez eperiod e medebelnvloe ddoo rd eteel tva ntomate ndi eresisten tware ntege n Cladospovium fulvum. Deresistenti etege n C. fulvum hadto tgevol gda tchemisch ebestrij - dingva ndez e ziekteachterweg ebleef ,waardoo rP . infestans dekan skree g zichongehinder dt eontwikkelen . Qmdatbehandelin gme tfungicide nnie taltij dafdoend ei se nresidue nva n fungicide-middelenhe taanzie ne nd econsumpti ekwalitei tva ntomate nnadeli g kunnenbelnvloeden ,i sresistenti edringen dgewenst
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