| Source | DF | Mean square | |
| Incidence | Severity | ||
| Replication | 3 | 185.0 | 102.5 |
| District (D) | 3 | 5126.3*** | 560.3*** |
| Fields (F) | 6 | 3919.0*** | 157.9*** |
| D × F | 18 | 2845.0*** | 229.6*** |
| Residual | 81 | 235.0 | 32.7 |