Evaluation on the efficacy of spinosad dust against major storage insect pests.

Abstract

AbstractLaboratory bioassays were conducted to compare the efficacy of spinosad dust (0.125%) admixed with shelled wheat grains with that of a cocktail of pirimiphos-methyl (1.6%) and permethrin (0.3%) as actellic super dust against Sitophilus zeamais, Tribolium castaneum, Rhyzopertha dominica and Prostephanus truncatus. Spinosad dust was applied at 0.35, 0.7 and 1.44 ppm, and actellic dust at 10.5 ppm. All treatments were significantly (P=0.05) better than the control except when applied against T. castaneum. Spinosad at 0.7 and 1.44 ppm controlled S. zeamais over the 24-week period. All treatments gave good control of P. truncatus and R. dominica, with no apparent significant differences (P=0.05) between treatments on the latter. On P. truncatus, spinosad showed better performance than actellic super dust (P=0.05). All levels of spinosad dust appeared to perform better on P. truncatus compared to actellic super; however, spinosad dust, unlike actellic super, was unable to control T. castaneum. The results suggest that spinosad dust may have potential in controlling major storage insect pests, with special applicability against the destructive larger grain borer, P. truncatus.