Additivity of action of three organophosphorus insecticides to some pests of stored grain, and the use of linear programming to identify minimum cost mixtures

Abstract

Dust formulations of malathion, pirimiphos methyl and etrimfos and their 1:1 w/w mixtures were bioassayed against six species of stored product beetle pests, including a specifically malathion resistant strain of Tribolium castaneum. The bioassay data was consistent with the hypothesis of additive action of the mixtures against the species tested. The use of linear programming to identify minimum cost insecticide mixtures in cases where the components act additively against a number of target pest species is illustrated