Toxicity of Selected Insecticides to Catolaccus hunteri (Hymenoptera: Pteromalidae) in the Laboratory

Abstract

Selected insecticides were evaluated in the laboratory for residual and topical toxicity to Catolaccus hunteri Crawford, a parasitoid of the pepper weevil, Anthonomus eugenii Cano. Based on predicted LC50 values, chlorpyrifos was highly toxic to the parasitoid both residually and topically, with LC 50 values of 0.029 and 0.292 μg[ai]/ mL, respectively. Indoxacarb was non-toxic, with LC 50 values of 42.842 and 225.961 μg[ai]/mL, respectively, for residual and topical exposure. Tebufenozide was non-toxic residually (LC 50 value of >135,940 μg[ai]/mL) but relatively toxic topically (LC 50 value of 0.221 μg[ai]/mL). LC 50 values of oxamyl and spinosad both residually (LC 50 values of 2.126 and 2.331 μg[ai]/mL, respectively) and topically (LC 50 values of 1.847 and 1.299 μg[ai]/mL, respectively) were intermediate between those of chlorpyrifos and indoxacarb. Methomyl was more toxic residually (LC 50 value of 0.029 μg[ai]/mL) than topically (LC 50 value of 0.292 μg[ai]/mL).