Foliar and tuber late blight resistance in a Solanum tuberosum potato mapping population

• Published in: Phytopathology Vol. 96; no. 6; p. S74
• Main Authors: Mayton, H, Simko, I, De Jong, W, Fry, W E
• Format: Journal Article
• Language: English
• Published: 01-06-2006
• Subjects: Phytophthora infestans; Solanum tuberosum
• ISSN: 0031-949X

Foliar and tuber resistance to Phytophthora infestans were evaluated in a mapping population (n = 94) developed between two Solanum tuberosum breeding lines, NY121 x NY115. Foliar disease severity of the progeny clones was measured by the area under the disease progress curve (AUDPC) in field tests in 2004 and 2005. Correlation analysis of AUDPC values with AFLP molecular markers revealed that 56%, 53%, and 52% of the quantitative phenotypic variance for resistance were associated with markers PCTMATC 184, PATMATA 171, and PATMACT 236, respectively, located on a chromosome V homolog derived from NY121 (P = 0.0001). In 2005, an additional 134 clones of the same population, not used in the initial marker analysis, were evaluated in the field and it was confirmed that these markers were associated with about 50% of the phenotypic variance (P = 0.0001) for foliar disease resistance. The genetic component of tuber blight variance was much smaller than the foliar blight component, but still these three markers were correlated (P = 0.01-0.10) with tuber blight resistance and explained 3-8% of the variance. Most markers associated with foliar resistance were not associated with tuber resistance.