Following signs according to Purdy H. W. et al. 1969 are used:
| Sign | Explanation |
| / | single cross |
| // | double cross |
| /n/ | multiple cross, where n= number of crosses |
| * n or n* | backcross, where n= number of backcrosses |
| ? | unknown pedigree |
| LV | local variety |
| M | mutation |
| S | selection |
| ML | multiline cultivar |
| + | pollen mixture pollination |
| /OP | open pollination |