Concentration and lethal time of toxic baits based on spinosyns on Ceratitis capitata and Diachasmimorpha longicaudata

Abstract

The use of toxic baits with spinosyns (spinosad and spinetoram), along with the parasitoid Diachasmimorpha longicaudata, is a sustainable alternative for the management of Ceratitis capitata. This study aimed to evaluate the lethal concentration (LC) and lethal time (LT) of spinosad and spinetoram, associated with the food lures sugarcane molasses at 7 %, Biofruit at 3 %, Ceratrap^® at 1.5 %, Flyral^® at 1.25 %, Isca Samaritá^® and Samaritá Tradicional^® at 3 %, on C. capitata, under laboratory conditions, as well as their effect, at the concentration of 96 mg L^-1, on D. longicaudata. For the lethal time data, mortality was assessed at 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 36, 48, 60, 72, 84 and 96 h after the exposure to the toxic baits. The lowest lethal concentrations (LC₅₀ and LC₉₅), to spinetoram (0.5 mg L^-1 and 3.7 mg L^-1, respectively) and spinosad (0.8 mg L^-1 and 7.8 mg L^-1, respectively), corresponded to the association with Samaritá Tradicional^® at 3 %. The lowest lethal time (TL₅₀), in hours, for the spinosad insecticide, corresponded to the formulation containing Biofruit at 3 % (6.6), and, to spinetoram, Samaritá Tradicional^® at 3 % (7.9). For D. longicaudata, the formulations that caused the lowest mortality corresponded to the association of Biofruit^® at 3 % with spinosad (4.7 %) and Samaritá Tradicional^® at 3 % with espinetoram (3.5 %). The toxic baits formulated with spinosad and espinetoram, associated with Isca Samaritá^® at 3 %, caused a mortality rate of more than 60 % to the parasitoid D. longicaudata.