| Source of variation | White grain | Yellow grain | ||
| Degrees of freedom | Middle square | Degrees of freedom | Middle square | |
| Tratamientos | 29 | 3,470,191* | 15 | 6,549,781** |
| Error | 238 | 2,122,618 | 106 | 1,698,916 |
| Total | 267 | 121 | ||