Summary
A resume is presented of the testing for late blight resistance conducted at Fredericton, New Brunswick, Canada during the past twenty years. The account is mainly concerned with the testing ofS. demissum x S. tuberosum hybrids.
Prior to 1949 there was little evidence for the existence of specialized races ofP. infestans and it is assumed that only the so-called common form of the fungus was prevalent in the field. In 1951 two seedlings, Keswick and Canso, hitherto considered risistant, blighted in the field. These varieties blighted again in 1952.
Isolates of the fungus from these two varieties behaved erratically in many cases when tested on a series of differential hosts obtained from Great Britain and the United States. Moreover, one of these isolates caused infection on all the differential hosts employed.
Existing schemes which have been proposed for the diffentiation of the races of this organism have been proven to be inadequate. Evidence has been presented indicating that blight resistance is governed by the action of more genes than those already postulated.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
Literature Cited
Black, William, 1952. Inheritance of resistance to blight (Phytophthora infestans) in potatoes. Proc. Roy. Soc. Edin., B., 64: 312–352.
Davies, W. M. 1936. Laboratory experiments on the effect of wind velocity on the flight ofMvsus persicae Sulz. Ann. Appl. Biol. 23: 401–408.
Mills, W. R. 1951. Twenty-second Annual Report to cooperators. The National Potato Breeding Program. Bur. of P1. Indus., Soils and Agr. Eng., U.S.D.A. 174–176.
Muller, K. O. and J. Munro. 1951. The reaction of virus-infected potato plants toPhytophthora infestans. Ann. Appl. Biol. 38: 765–773.
Reddick, D. 1928. Blight-resistant potatoes. Phytopath. 6: 483–500.
— and W. Mills. 1938. Building up virulence inPhytophthora infestans. Amer. Potato Jour. 15: 29–34.
Author information
Authors and Affiliations
Additional information
Contribution No. 1315 from the Botany and Plant Pathology Division, Department of Agriculture, Ottawa, Canada.
Rights and permissions
About this article
Cite this article
Howatt, J.L., Hodgson, W.A. Testing for late blight resistance in the potato in Canada. American Potato Journal 31, 129–140 (1954). https://doi.org/10.1007/BF02859993
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF02859993