Summary
A collection of 80 isolates ofPhytophthora infestans, representing multilocus genotypes of the pathogen found in Canada from 1994 to 1996, was screened on a series of nine differential potato host cultivars to determine the physiological race of the isolates. A total of 28 pathotypes were found among the 11 genotypes present in the collection. There was a significant increase in the complexity of pathotypes from 1994 to 1996 which reflected the displacement of the US-1 genotype (mean of 2.2 host differentials infected) by the US-8 genotype (mean of 8.1 host differentials infected). Eighteen of the US-8 isolates could overcome all nine of the resistance genes tested. Virulence genes which overcame host resistance conferred by R8 were the rarest in the populations studied. The predominance of complex populations ofP. infestans in Canada implies that the introduction of cultivars with specific R genes for resistance would be an ineffective control measure.
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References
Andrivon, D., 1994a. Races ofPhytophthora infestans in France, 1991–1993.Potato Research 37: 279–286.
Andrivon, D., 1994b. Race structure and dynamics in populations ofPhytophthora infestans.Canadian Journal of Botany 72: 1681–1687.
Black, W., C. Mastenbroek, W.R. Mills & L.C. Peterson, 1953. A proposal for an international nomenclature of races ofPhytophthora infestans and of genes controlling immunity inSolanum demissum derivatives.Euphytica 2: 173–178.
Bradshaw, J.E., R.L. Wastie, H.E. Stewart & G.R. Mackay, 1995. Breeding for resistance to late blight in Scotland. In: L.J. Dowley, E. Bannon, L.R. Cooke, T. Keane & E. O'Sullivan (Eds),Phytophthora infestans 150. Boole Press Ltd., Dublin, Ireland.
Chalmers, K.J., R. Waugh, J.I. Sprent, A.J. Simons & W. Powell, 1992. Detection of genetic variation between and within populations ofGliricidia sepium andG. maculata using RAPD markers.Heredity 69: 465–472.
Chycoski, C.I. & Z.K. Punja, 1996. Characteristics of populations ofPhytophthora infestans from potato in British Columbia and other regions of Canada during 1993 to 1995.Plant Disease 80: 579–589.
Deahl, K.L., D.A. Inglis & S.P. DeMuth, 1993. Testing for resistance to metalaxyl inPhytophthora infestans isolates from northwestern Washington.American Potato Journal 70: 779–795.
Doling, D.A., 1956. Distribution of physiological races ofPhytophthora infestans (Mont.) de Bary in Northern Ireland.Nature 177: 230.
Dowley, L.J., D.G. Routley & L.C. Peirce, 1975. Ontogenetic predisposition of tomato foliage to race 0 ofPhytophthora infestans.Phytopathology 65: 1422–1424.
Forbes, G.A., X.C. Escobar, C.C. Ayala, J. Revelo, M.E. Ordo nez, B.A. Fry, K. Doucett & W.E. Fry, 1997. Population genetic structure ofPhytophthora infestans in Ecuador.Phytopathology 87: 375–380.
Fry, W.E., A. Drenth, L.J. Spielman, B.C. Mantel, L.C. Davidse & S.B. Goodwin, 1991. Population genetic structure ofPhytophthora infestans in The Netherlands.Phytopathology 81: 1330–1336.
Gisi, U. & Y. Cohen, 1996. Resistance to phenylamide fungicides: A case study withPhytophthora infestans involving mating type and race structure.Annual Review of Phytopathology 34: 549–572.
Goodwin, S.B., R.W. Allard, S.A. Hardy & R.K. Webster, 1992. Hierarchical structure of pathogenic variation amongRhynchosporium secalis populations in Idaho and Oregon.Canadian Journal of Botany 70: 810–817.
Goodwin, S.B., B.A. Cohen, K.L. Deahl & W.E. Fry, 1994. Migration from northern Mexico as the probable cause of recent genetic changes in populations ofPhytophthora infestans in the United States and Canada.Phytopathology 84: 553–558.
Goodwin, S.B., C.D. Smart, R.W. Sandrock, K.L. Deahl, Z.K. Punja & W.E. Fry, 1998. Genetic change within populations ofPhytophthora infestans in the United States and Canada during 1994 to 1996: Role of migration and recombination. Phytopathology 88: 939–949.
Goodwin, S.B., L.S. Sujkowski, A.T. Dyer, B.A. Fry & W.E. Fry, 1995a. Direct detection of gene flow and probable sexual reproduction ofPhytophthora infestans in northern North America.Phytopathology 85: 473–479.
Goodwin, S.B., L.S. Sujkowski & W.E. Fry, 1995b. Rapid evolution of pathogenicity within clonal lineages of the potato late blight disease fungus.Phytopathology 85: 669–676.
Graham, K.M., 1955. Distribution of physiological races ofPhytophthora infestans (Mont.) de Bary in Canada.American Potato Journal 32: 277–282.
Graham, K.M., L.A. Dionne & W.A. Hodgson, 1961. Mutability ofPhytophthora infestans on blight-resistant selections of potato and tomato.Phytopathology 51: 264–265.
Graham, K.M., J.S. Niederhauser & S. Romero, 1959. Observations of races ofPhytophthora infestans in Mexico during 1956–1957.American Potato Journal 36: 196–203.
Howatt, J.L., 1957. The late blight disease of potatoes and its causal fungus in Canada.American Potato Journal 34: 185–192.
Kato, M., E.S. Mizubuti, S.B. Goodwin & W.E. Fry, 1997. Sensitivity to protectant fungicides and pathogenic fitness of clonal lineages ofPhytophthora infestans in the United States.Phytopathology 87: 973–978.
Lambert, D.H. & A.I. Currier, 1997. Differences in tuber rot development for North American clones ofPhytophthora infestans.American Potato Journal 74: 39–43.
Malcolmson, J.F., 1969. Races ofPhytophthora infestans occurring in Great Britain.Transactions of the British Mycological Society 53: 417–423.
Malcolmson, J.F., 1979. Isolation and identification of races ofPhytophthora infestans from breeders' assessment plots.Transactions of the British Mycological Society 73: 155–156.
Miller, J.S. & D.A. Johnson, 1997. Aggressiveness ofPhytophthora infestans genotypes on potato stems and leaves.Phytopathology 87: S66.
Mills, W.R. & J.S. Niederhauser, 1953. Observations on races ofPhytophthora infestans in Mexico.Phytopathology 43: 454–455.
Niederhauser, J.S. & W.R. Mills, 1953. Resistance ofSolanum species toPhytophthora infestans in Mexico.Phytopathology 43: 456–457.
O'Sullivan, E. & L.J. Dowley, 1983. Physiological specialisation in strains ofPhytophthora infestans sensitive and resistant to metalaxyl.Irish Journal of Agricultural Research 22: 105–107.
Peever, T.L. & M.G. Milgroom, 1994. Genetic structure ofPyrenophora teres populations determined with random amplified polymorphic DNA markers.Canadian Journal of Botany 72: 915–923.
Peters, R.D., 1998. Characterization of evolving populations ofPhytophthora infestans causing late blight of potato in Canada. PhD thesis. The University of Guelph.
Pietkiewicz, J.B., 1978. Pathogenic variation among field isolates ofPhytophthora infestans.Phytopathologische Zeitschrift 93: 289–294.
Plank, J.E. van der, 1968. Disease resistance in plants. Academic Press, NY, 206 pp.
Platt, H.W. (Bud) 1994. Survey for the presence of A2 mating type and metalaxyl-insensitive strains of the causal agent of potato late blight.Canadian Plant Disease Survey 74: 112.
Rivera-Peña, A., 1990. Wild tuber-bearing species of Solanum and incidence ofPhytophthora infestans (Mont.) de Bary on the Western slopes of the volcano Nevado de Toluca. 3. Physiological races ofPhytophthora infestans.Potato Research 33: 349–355.
Rivera-Peña, A., 1995. Racial composition in a population ofPhytophthora infestans (Mont.) de Bary in the Toluca Valley and slopes of the volcano Nevado de Toluca over the period 1989–1994. In: L.J. Dowley, E. Bannon, L.R. Cooke, T. Keane & E. O'Sullivan (Eds),Phytophthora infestans 150. Boole Press Ltd., Dublin, Ireland.
Schöber-Butin, B., G. Knapova, I. Knipfelberg & F. Niepold, 1995.Phytophthora infestans in Germany: population dynamics and modern methods in diagnosis. In: L.J. Dowley, E. Bannon, L.R. Cooke, T. Keane & E. O'Sullivan (Eds),Phytophthora infestans 150. Boole Press Ltd., Dublin, Ireland.
Stewart, H.E., 1990. Effect of plant age and inoculum concentration on expression of major gene resistance toPhytophthora infestans in detached potato leaves.Mycological Research 94: 823–826.
Świeżyński, K.M., L. Domański, S. Sobkowiak & H. Zarzycka, 1996. Reaction toPhytophthora infestans of potato genotypes with race-specific resistance.Potato Research 39: 195–203.
Tooley, P.W., W.E. Fry & M.J. Villarreal Gonzalez, 1985. Isozyme characterization of sexual and asexualPhytophthora infestans populations.Journal of Heredity 76: 431–435.
Tooley, P.W., J.A. Sweigard & W.E. Fry, 1986. Fitness and virulence ofPhytophthora infestans isolates from sexual and asexual populations.Phytopathology 76: 1209–1212.
Tooley, P.W., C.D. Therrien & D.L. Ritch, 1989. Mating type, race composition, nuclear DNA content, and isozyme analysis of Peruvian isolates ofPhytophthora infestans.Phytopathology 79: 478–481.
Turkensteen, L.J., 1989. Interaction of R-genes in breeding for resistance of potatoes againstPhytophthora infestans. In: Fungal Diseases of the Potato. Report of the planning conference, CIP, Lima.
Watson, I.A., 1970. Changes in virulence and population shifts in plant pathogens.Annual Review of Phytopathology 8: 209–230.
Yeh, F.C., D.K.X. Chong & R.-C. Yang, 1995. RAPD variation within and among natural populations of trembling aspen (Populus tremuloides Michx.) from Alberta.Journal of Heredity 86: 454–460.
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Peters, R.D., Platt, H.W.(. & Hall, R. Changes in race structure of Canadian populations ofPhytophthora infestans based on specific virulence to selected potato clones. Potato Res 41, 355–370 (1998). https://doi.org/10.1007/BF02358968
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DOI: https://doi.org/10.1007/BF02358968