| % | Frequencies | Helpers to know the residual effect of pesticides |
| 3 | 3 | Agricultural extension |
| 3 | 3 | Protection |
| - | - | Agricultural research |
| - | - | Farmers’ union |
| 38 | 38 | Commercial companies |
| 39 | 39 | Friends |
| 100 | 100 | Total |