Table 1 Means and variances for percent tuber dry matter, tuber eye depth and uniformity of tuber shape in breeding clones, accessions held by NordGen and cultivars grown today by Nordic farmers using a scale ranging from 1 (non-uniform) to 9 (uniform) for tuber shape uniformity, from 1 (deep) to 9 (shallow) for tuber eye depth, and 1 (low) to 9 (high) for percent dry matter content in tubers

From: Diversity and population structure of Nordic potato cultivars and breeding clones