ARS | Publication request: FOLIAR RESISTANCE TO LATE BLIGHT IN POTATO CLONES EVALUATED IN NATIONAL TRIALS IN 1998

Submitted to: American Journal of Potato Research
Publication Type: Abstract Only
Publication Acceptance Date: May 18, 1999
Publication Date: N/A

Technical Abstract: With the emergence of new and more aggressive strains of Phytophthora infestans an evaluation of potato clones for resistance to late blight is necessary. Thirty-five potato clones (12 cultivars, 14 selections, 9 differentials) were evaluated in 1998 for late blight resistance at eight U.S. locations. The US-8 or US-11 strains of P. infestans were 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 nonparametric 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, and B0718-3. These clones are important breeding materials for resistance to P. infestans. AUDPC was minimal in the differentials LBR-8 and LBR-9.