Submitted to: American Journal of Potato Research
Publication Type: Abstract Only
Publication Acceptance Date: May 18, 1999
Publication Date: N/A
With the emergence of new and more aggressive strains of Phytophthora infestans an evaluation of potato clones for resistance to late blight is necessary. Twenty-two potato clones (10 cultivars, 12 selections) were evaluated in 1997 for late blight resistance at seven U.S. locations. The US-8 strain of P. infestans was present. Percent infected foliage was recorded at approximately weekly intervals following the onset of disease. Area under the disease progress curve (AUDPC) was calculated. The non-parametric stability statistics mean absolute rank differences and variances of the ranks were analyzed for phenotypic stability. Both of these statistics were significant, indicating the importance of genotype x environment interaction on the rankings of these clones across locations. The most late blight resistant clones were AWn86514-2, B0692-4, B0718-3 and B0767-2. The most susceptible clones were B1004-8, NorDonna, Krantz, and Libertas.