METHOD: Visual Examination CONDITIONS: Green House - 16h light METHOD NARR: Plants were grown from tubers. A single mature leaf 7-8 nodes down from the meristem was removed with a razor. The detached leaf was inoculated with P.6 and 11 days later. Disease severity index is based on percentage of leaf area affected: 0 = no symptoms, 1 = 0-5%, 3 = 6-25%, 5 = 26-50%, 7 = 51-75%, 9 = 76-100%. RESULTS NARR: Pnt was predominantly resistant with someotypes. Cph subsp. ehr were mostly susceptible except for 275215 which were resistant. Cph subsp. cph displayed a mix of phenotpes. AUTHOR EXPLANATION: Crosses were made to generate a family segregating for late-blight res late-blight resistance locus was mapped to chromosome 7.