Evaluation of pesticides for controling the pest complex on cabbage in the uplands of Sri Lanka

Abstract

Field screening of pesticides conducted at the Agricultural Research Station, Sita Eliya in Maha 1976/77 and Yala 1977 indicated low pest incidence in Yala compared to Maha. In Yala considerable reduction in pesticide use could be effected without affecting the yield significantly. Though the synthetic pyrethroids permelhrin and fenvalerate were superior to the organophosphate and carbamate insecticides, their harmful effects on the natural enemies and rapid development of resistance preclude their being recommended in Sri Lanka. Of the other insecticides chlorpyrifos was the best Pirimiphos-methyl and methomyl though less effective against the cutworms than methamidophos could be recommended for use against the other pests of cabbage. These three insecticides gave better returns and are less hazardous to mammals than methamidophos.