ALTERNATIVES TO REGULAR INSECTICIDE APPLICATIONS FOR CONTROL OF LEPIDOPTEROUS PESTS OF BRASSICA-OLERACEA VAR CAPITATA

Two field trials were performed to assess a variety of control methods for larvae of diamondback moth, Plutella xylostella (L.) and cabbage white butterfly, Pieris rapae (L.) on cabbage. The possibility of redu cing the number of synthetic insecticide applications, by spraying acc ording to action thresholds, was also studied. The plant-based product rotenone, the bacterium Bacillus thuringiensis Berliner and a lightwe ight netting barrier successfully controlled the pests and produced ca bbage of marketable quality. Pyrethrum, garlic, soap and combinations of these products did not prevent larval feeding damage. Use of action thresholds reduced numbers of synthetic insecticide applications, in one season, without compromising yield or quality. Results of these tr ials show that there is potential for reducing synthetic insecticide i nput in the production of quality cabbage crops.