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Resistance to Phytophthora Infestans in Solanum Tuberosum and Wild Solanum Species

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Resistance to Phytophthora Infestans in Solanum Tuberosum and Wild Solanum Species Resistance to Phytophthora infestans in Solanum tuberosum and wild Solanum species. Leontine Colon Promotor: dr. ir. J.E. Parlevliet hoogleraar in de plantenveredeling Resistance to Phytophthora infestans in Solanum tuberosum and wild Solanum species. Resistentie tegen Phytophthora infestans in S. tuberosum en wilde Solanum ĉsoorten Leontine Colon Proefschrift ter verkrijging van de graad van doctor in de landbouwĉen milieuwetenschappen op gezag van de rector magnificus, dr. C.M. Karssen, in het openbaar te verdedigen op vrijdag 20 mei 1994 des namiddags te half twee in de Aula van de Landbouwuniversiteit te Wageningen Aan mijn ouders CIP GEGEVENS KONINKLIJKE BIBLIOTHEEK, DEN HAAG Colon, L.T. Resistance to Phytophthora infestans in Solanum tuberosum and wild Solanum species / Leontine Colon. ĉ [S.I. : s.n.]. Thesis Wageningen ĉ With ref. ĉ With summaries in English and Dutch. ISBN 90ĉ5485ĉ226ĉ7 Keyĉwords: infection efficiency, late blight, latent period, lesion growth rate, photoperiod, Phytophthora infestans, potato, resistance, Solanum tuberosum, S. arnezii x hondelmannii, S. berthaultii, S. circaeifolium, S. leptophyes, S. microdontum, S. nigrum, S. sparsipilum, S. venturii, S. vernei, S. verrucosum, S. villosum, S. demissum , sporulation capacity Cover design: Ernst van Cleef Printed by Ponsen & Looijen BV, Wageningen Abstract Resistance to Phytophthora infestans , the causal agent of late blight, is present in the potato, Solanum tuberosum , and in many wild relatives of this crop. The resistance of S. tuberosum is partial and, though helpful in reducing the use of fungicides, is not sufficient to fully solve the problem. It also has the disadvantage of being associated with late maturity. Since 1910, other genes for resistance have been introduced into the potato genepool from the Mexican species S. demissum . These genes, designated R genes, initially supplied complete protection from the disease, but the pathogen soon managed to overcome the resistance of these genes, which is no longer useful. This thesis describes several other wild Solanum species as potential donors of resistance to P. infestans . Firstly, the partial resistance of a number of old cultivars of S. tuberosum was studied, and appeared to be durable. In the South American species S. berthaultii , S. circaeifolium, S. microdontum and S. venturii , both partial and (nearly) complete resistance were found, while S. arnezii x hondelmannii, S leptophyes, S. sparsipilum and S. vernei carried promising partial resistances. The Mexican species S. verrucosum was also found to be highly resistant. Crosses with susceptible diploid S. tuberosum revealed the presence of major genes in S. microdontum, while minor genes appeared to be important in S. arnezii x hondelmannii . Complementary action of major genes from one of the susceptible S. tuberosum parents was also found. A wide genetic variation was found with these species for the components of resistance infection efficiency (IE), lesion growth rate (LGR) and sporulation capacity (SC), while latent period (LP) was found to vary less. In S. tuberosum , IE, LGR and SC and in S. microdontum IE, LGR and LP appeared intercorrelated. Results supported the suggested role of glandular trichomes in the resistance of S. berthaultii. The resistance of some S. tuberosum cultivars appeared to be lost at short photoperiods. A similar, though much smaller loss was observed for the partial resistance of S. microdontum . The resistance of the nonhost species S. nigrum , evolved in India, was found to be of a preĉhaustorial nature, and associated with a hypersensitive reaction. This resistance was transferred to sexual hybrids with S. tuberosum and S. demissum . Voorwoord Dit proefschrift doet verslag van acht jaar onderzoek aan een complex probleem, namelijk het opsporen van duurzame resistentie tegen Phytophthora infestans , de aardappelziekte, bij aardappel. De basis voor het werk met de beschreven wilde soorten werd gelegd door mijn voorganger bij de toenmalige SVP, André Beekman, die de door mij gebruikte genenbankaccessies uitkoos en daar de eerste toetsingen mee verrichtte; zijn voorwerk gaf dus de aanzet tot dit proefschrift. Het meeste werk werd verricht door Dirk Budding, die met vaardige hand en met inzicht de vele kasĉ en veldproeven uitvoerde, ook in de avonduren, weekends en soms zelfs vakanties. Zijn realistische kijk op de praktische uitvoerbaarheid van sommige experimenten bleek meerdere malen de juiste, en heeft zeker bijgedragen tot het welslagen van veel experimenten. Voor je inzet, en voor je bijdrage aan de goede werksfeer, wil ik je dan ook hartelijk bedanken. Mijn dank geldt ook Luc Sijpkes, die vaak te hulp schoot waar wij handen te kort kwamen. Veel andere collega's van CPROĉDLO hebben ertoe bijgedragen dat ik de afgelopen acht jaar met plezier heb gewerkt. Ik kan ze niet allemaal noemen, maar enkelen wil ik toch met name bedanken. Coosje Hoogendoorn, verantwoordelijk voor het onderzoek van de afdeling, jij hebt met je heldere, opbouwende kritiek zeker bijgedragen aan de totstandkoming van dit proefschrift, en daarvoor mijn dank. Paul Keizer, jij hebt me geweldig geholpen met het bespelen van Genstat, wat je veel tijd heeft gekost en waarvoor je eigenlijk altijd klaarstond, wanneer dat maar mogelijk was. Zonder jouw hulp zat ik nu ongetwijfeld nog in de eerste berekeningen verstrikt. Heel erg bedankt. Frits Arntzen, wij hebben vele jaren samen onze werkkamer gedeeld, hetgeen erg gezellig was, bedankt daarvoor. De collega's van de afdeling Akkerbouwĉ en Voedergewassen, ook hen die inmiddels niet meer bij ons werkzaam zijn, wil ik bedanken voor hun collegialiteit, en voor de prettige sfeer op de afdeling. Hetzelfde geldt de overige collega's van CPROĉDLO. Daarnaast dank ik de leden van de NRLOĉwerkgroep Phytophthora infestans, voor hun welwillende aandacht en stimulerende discussies. Mijn bijzondere dank gaat uit naar Lo Turkensteen van het IPOĉDLO, die mij met veel deskundige raad en daad terzijde heeft gestaan. Mijn dank gaat ook uit naar de studenten, gastmedewerkers en vrijwilligers die aan het Phytophthora ĉproject hebben meegewerkt: Martin Pieters, die een aantal kasĉen veldproeven uitvoerde en uitwerkte, Martine van Ijzendoorn en Johannes Kalma, die een bijdrage hebben geleverd aan het histologische werk, en Waldek Marczewski and Bogdan Flis from the Instytut Ziemniaka in M/,lochow, Poland, who spent three months of their life to stay and work with us . Allemaal bedankt. Thank you all . Ik wil ook mijn promotor, professor Jan Parlevliet, bedanken voor zijn inspanningen en voor zijn commentaar op de manuscripten. Geen proefschrift, ook het mijne niet, komt tot stand zonder medewerking van het thuisfront. Ronald, jij hebt je, vooral de afgelopen paar maanden, geweldig ingespannen om alles op rolletjes te laten lopen, terwijl ik achter de computer zat te schrijven. Ik had het voorrecht om jou niet alleen als vriend, maar ook als collega en vakgenoot naast me te hebben, en dat heeft geleid tot veel waardevolle discussies, ook over dit proefschrift. Daarnaast ben jij natuurlijk degene geweest die de aanzet gaf en geeft tot het werk met Solanum nigrum , hetgeen een duidelijke plaats in mijn proefschrift heeft gekregen. Voor al deze bijdragen ben ik je erg dankbaar. Het is uiteraard nog te vroeg om te denken dat met de beschreven resultaten het doel bereikt is; dat is pas het geval wanneer er aardappelrassen met deze resistenties zijn ontstaan, die in de praktijk hun waarde hebben bewezen. Ik wil dan ook de kweekbedrijven veel succes toewensen in hun moeilijke taak, en de hoop uitspreken dat het fytopathologische en veredelingsonderzoek de komende jaren, met de huidige snelle ontwikkeling van nieuwe technieken en inzichten, hieraan een belangrijke bijdrage zal kunnen leveren. Contents Introduction 11 Chapter 1. Durable resistance to late blight ( Phytophthora infestans ) in old potato cultivars 15 Chapter 2. Resistance to late blight ( Phytophthora infestans ) in 10 wild Solanum species 31 Chapter 3. Partial resistance to late blight ( Phytophthora infestans ) in hybrid progenies of four South American Solanum species crossed with diploid S. tuberosum 47 Chapter 4. Components of resistance to late blight ( Phytophthora infestans ) in eight South American Solanum species 67 Chapter 5. The influence of daylength on the expression of resistance to Phytophthora infestans in Solanum tuberosum and S. microdontum 93 Chapter 6. Resistance to Phytophthora infestans in Solanum nigrum , S. villosum and their sexual hybrids with S. tuberosum and S. demissum 111 General discussion 127 Summary 141 Samenvatting 145 References 149 Curriculum vitae 159 Note Some chapters of this thesis are based on the following papers: Colon, L.T., L.J., Turkensteen, W. Prummel, D.J. Budding & J. Hoogendoorn. Durable resistance to late blight ( Phytophthora infestans ) in old potato cultivars. Submitted. (Chapter 1). Colon, L.T. & D.J. Budding, 1988. Resistance to late blight ( Phytophthora infestans ) in ten wild Solanum species. Euphytica S: 77ĉ86. (Chapter 2) Colon, L.T., Jansen, R.C. & Budding, D.J. Partial resistance to late blight (Phytophthora infestans ) in hybrid progenies of four South American Solanum species crossed with diploid S. tuberosum. Submitted. (Chapter 3). Colon, L.T., D.J. Budding, L.C.M. Keizer & M.M.J. Pieters. Components of resistance to late blight ( Phytophthora infestans ) in wild tuberĉbearing South American Solanum species. Submitted. (Chapter 4). Colon, L.T., D.J. Budding & J. Hoogendoorn. The influence
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