| Nitrogen source (N) (kg∙ha−1) | Internal use efficiency (IUE) (kg∙kg−1) | Reciprocal of internal use efficiency (RIE) (kg∙kg−1) |
| BRRI dhan28 | ||
| Control | 86 | 12 |
| Urea | 71 | 15 |
| Urea + CD | 62 | 16 |
| CD | 56 | 18 |
| Urea + PM | 62 | 16 |
| PM | 75 | 14 |
| Avg. | 69 | 15 |
| BRRI dhan29 | ||
| Control | 94 | 11 |
| Urea | 77 | 14 |
| Urea + CD | 67 | 15 |
| CD | 64 | 16 |
| Urea + PM | 72 | 14 |
| PM | 81 | 13 |
| Avg. | 76 | 14 |
| LSD0.05 for N | 15.02 | 2.91 |
| LSD0.05 for V | NS | NS |
| LSD0.05 for N × V | NS | NS |
| CV (%) | 20.4 | 19.7 |