Laboratory Toxicity of Insecticides to Workers of Trigona Spinipes (F., 1793) (Hymenoptera, Apidae)

SummaryThe laboratory LD50 values of organophosphate, carbamate, organochlorine (including cyclodienes) and pyrethroid insecticides were determined for workers of Trigona spinipes (F., 1793). Determinations used topical application techniques from which dose-mortality was derived using Bliss' method (1935). In order of decreasing toxicity the LD50 values for workers, in μg/bee were as follows: heptachlor, 0·0168; dieldrin, 0·0289; Cypermethrin, 0·0704; permethrin, 0·0724; parathion, 0·0956; lindane, 0·1331; methomyl, 0·1402; dicrotophos, 0·685; endosulfan, 0·2097; malathion, 0·2649; acephate, 0·4234; carbaryl, 0·7472; fenvalerate, 1·0880. The insecticides tested were highly toxic to T. spinipes.