| Generation | No. Plants | Expected ratio | χ2 | P | |
| Resistant | Susceptible | ||||
| P1 | 40 | 0 | - | - | - |
| P2 | 0 | 30 | - | - | - |
| BC2F1 | 26 | 37 | 3:1 | 38.23 | <0.0001 |