Here, we are talking about the farmers that previously farmers have used different methods to save their crops from pests and diseases. The option "Traditionally" is correct in this context. Meanings: Occasionally: at infrequent or irregular intervals; now and then Mainly: more than anything else; mostly Traditionally: as part of a long-established custom, practice, or belief; typically Fanatically: motivated or characterized by an extreme, uncritical enthusiasm or zeal, as in religion or politics