American Potato Journal

, Volume 33, Issue 10, pp 287–295 | Cite as

Differential reaction of potato hosts to foreign and domestic potato physiologic races of phytophthora infestans

  • R. Pristou
  • M. E. Gallegly


The potato physiologic races of P. infestans and genes for resistance reported by Black in Scotland, Mastenbroek in the Netherlands, and Mills and Peterson in the United States were found to match or fall into a definite pattern of relationship. Ten distinct isolate groups identified from the reactions of the isolates on the three sets of differential hosts matched the international races 1; 2; 4; 1,2; 1.4; 2,4; 1,2.4; 1,3,4; and 2,3,4. Canadian isolates were identified as races 1,2; 1,2,3; 1,2,4; and 1,2,3,4. One West Virginia isolate was identified as race 3. These 13 different races together with 2 others (1,3 and 3,4) described by Black but not available for study, bring the total number of potato races of P. infestans found to fifteen. Only race 2,3 has not been found from the possible sixteen that can be identified on present differential hosts. The results confirm the interrelationship of genes and races reported in a joint paper by the above four authors. A few isolates gave reactions different from those described for them, but they reacted as one of the other races. Either the cultures were mis-labeled or changed while growing in pure culture. Therefore, the proposed international system of designating potato races of P. infestans and genes for resistance to these races appears to be a valid and workable one for the present.


AMERICAN Potato Journal Phytophthora Infestans Potato Jour Physiologic Race Differential Host 
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Literature Cited

  1. 1.
    Black, W. 1952. A genetic basis for the classification of strains ofPhytophthora infestans. Proc. Roy. Soc. Edin., B. 65: 36–51.Google Scholar
  2. 2.
    —, C. Mastenbroek, W. R. Mills, and L. C. Peterson. 1953. A proposal for an international nomenclature of races ofPhytophthora infestans and of genes controlling immunity inSolanum demissum derivatives. Euphytica 2: 173–179.CrossRefGoogle Scholar
  3. 3.
    Gallegly, M. E. 1955. Physiologic races ofPhytophthora infestans; their use in breeding for resistance. (Abs.) Phytopath. 45: 464.Google Scholar
  4. 4.
    Mastenbroek, C. 1952. Investigations into the inheritance of the immunity fromPhytophthora infestons de Bary ofSolanum demissum Lindl. Euphytica 1: 187–198.CrossRefGoogle Scholar
  5. 5.
    —. 1953. Experiments on the inheritance of blight immunity in potatoes derived fromSolanum demissum Lindl. Euphytica 2: 197–206.CrossRefGoogle Scholar
  6. 6.
    Mills, W. R. and L. C. Peterson. 1949. Potato blight investigations. (Abs.) Amer. Potato Jour. 26: 98.Google Scholar
  7. 7.
    — and -L. C. Peterson. 1952. The development of races ofPhytophthora infestans (Mont.) deBary on potato hybrids. (Abs.) Phytopath. 42: 26.Google Scholar
  8. 8.
    Pristou, R. and M.E. Gallegly. 1954. Differential reaction of potato hosts to foreign and domestic physiologic potato races ofPhytophthora infestans. (Abs.) Amer. Potato Jour. 31: 372–373.Google Scholar
  9. 9.
    Reddick, D. and W. R. Mills. 1938. Building up virulence inPhytophthora infestons. Amer. Potato Jour. 15: 29–34.CrossRefGoogle Scholar
  10. 10.
    Wilson, J. B. and M. E. Gallegly. 1955. The interrelationship of potato and tomato races ofPhytophthora infestons. Phytopath. 45: 473–476.Google Scholar

Copyright information

© Springer 1956

Authors and Affiliations

  • R. Pristou
    • 1
  • M. E. Gallegly
    • 2
  1. 1.C. A. Swanson and SonsOmaha
  2. 2.West Virginia Agricultural Experiment StationMorgantown

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