| Code | Definition | Number of Accessions |
| 1 | very short < 8,0 cm - line >12,0 cm - population, hybrid | 4 |
| 2 | 8,0- 9,0 cm - line 12,0-14,0 cm - population, hybrid | 5 |
| 3 | short 9,1-10,0 cm - line 14,1-16,0 cm - population, hybrid | 13 |
| 4 | 10,1-11,0 cm - line 16,1-18,0 cm - population, hybrid | 19 |
| 5 | intermediate 11,1-12,0 cm - line 18,1-20,0 cm - population, hybrid | 40 |
| 6 | 12,1-14,0 cm - line 20,1-22,0 cm - population, hybrid | 8 |