| Class |
it |
Description of symptom |
| Immune |
0 |
No sign of infection to the naked eye |
| Very resistant |
0: |
No uredia, but distinct flakes of varying sizes, usually a chlorotic yellow but occasionally necrotic |
| Resistant |
1 |
Small uredia surrounded by yellow chlorotic and necrotic area |
| Moderately resistant |
2 |
Small to medium sizeduredia, typically in a dark green island surrounded by a chlorotic area |
Mesothentic or
Heterogeneous |
X |
A range of infection type from resistant to susceptible scattered randomly on a single leaf caused by a single isolate not a mixture |
| Moderately Susceptible |
3 |
Medium sized uredia. Usually surrounded by a light green chlorotic |
| Susceptible |
4 |
Large uredia with limited amount of chlorosis: may be diamond shaped |
| Modified character |
| Lower uredinia |
= |
Uredia much smaller than than typical and at the lower limit of the infection type |
| Small uredinia |
- |
Uredia smaller than normal |
| Larger uredinia |
+ |
Uredia larger than normal |
| Largest uredinia |
++ |
Uredia much larger than typical and at the upper limit for the infection type |