| Treatments | RI | RII | RIII | Mean |
| T1 = Control (no urea) | 112.3 | 98.6 | 108.6 | 106.5 |
| T2 = Recommended urea soil applied (130 kg・ha−1) | 168.9 | 161.5 | 160.6 | 163.7 |
| T3 = 1% urea at 35 days after sowing | 171.6 | 181.6 | 185.6 | 179.6 |
| T4 = 1% urea at 60 days after sowing | 172.6 | 179.6 | 181.5 | 177.9 |
| T5 = 1% urea at 85 days after sowing | 170.6 | 176.6 | 176.6 | 174.6 |