Evaluation location: Wisconsin, United States
In 2006, 12 random seedlings per accession were transplanted into each of two replications at the Hancock Wisconsin Agricultural Experiment Station. A randomized complete block design was used. Four tubers from Red Norland potatoes also were planted after every 10 plots to provide susceptible check plants. Standard irrigation and cultural practices were used in the field, except that pesticides were not used to control Colorado potato beetle. Each plot of 12 plants was visually scored for percentage of defoliation on 2, 9, 16, and 22 August (Horton et al. 1997). The area under the defoliation progress (AUDPC) curve was calculated for each accession based on percent defoliation on the four score dates. Low scores indicate resistance to CPB.