Abstract:In order to reasonably utilize resistant potato resources and cost-effectively control potato Fusarium dry rot, resistance of 35 potato varieties to the dominant pathogens, F.sambucinum and F.solani, were evaluated. Tubers of these varieties were inoculated with the mixture of F.sambucinum isolates and the mixture of F.solani isolates respectively. The radius of rotting spots of inoculated tubers on the 15th day after inoculation was analyzed via DPS2000 Data Processing System. The results showed that the best clustering effect were at the optimal composition of the original data unconverted for Fusarium sambucinum, and the original data standardized for F.solani, combined with euclidean distance and the longest distance method together, which had best degree of agreement with the inoculation results. The 35 potato varieties were grouped into three groups of 11 resistant, 17 medium resistant and 7 susceptible varieties at grouping point 21 of euclidean distance for tubers’ resistance to F.sambucinum, while three groups of 13 resistant, 14 medium resistant and 8 susceptible varieties at grouping point 3.0 of euclidean distance for resistance to F.solani.