Skin color at the head of tuber
| Code | Term | Description |
|---|---|---|
| 1 | White | |
| 2 | Yellowish white to off white | |
| 3 | Yellow | |
| 4 | Orange | |
| 5 | Light purple | |
| 6 | Purple | |
| 7 | Purple with white | |
| 8 | White with purple | |
| 9 | Yellow with purple | |
| 10 | White with pink | |
| 11 | Outer purple/inner yellowish | |
| 12 | White with yellow | |
| 13 | Yellow orange |