Mortility of natives bees for insecticides by ingestion

Abstract

Bees are social insects of extreme relevance to ecosystems, as they are the main responsible for pollination in natural and agricultural environments. Inappropriate use of insecticides has been reported as one of the factors that threatens the survival of these organisms. Thus, three insecticides (imidacloprid, deltamethrin and spinetoram) were used in this study to determine dose-mortality curves in native bees Nannotrigona sp. by ingestion. For this, forage workers were exposed to diets of honey and water (1:1 v/v) contaminated with insecticides (6 to 7 doses). All the insecticides were toxic to the forage workers, especially imidacloprid, the most toxic of the three, followed by spinetoram and deltamethrin (LD 50 = 0.5, 7.1 and 72.5 ng/bee, respectively). The results confirm the undersired impacts of these substances and alert to na even more effective search for alternatives that do not reach these non-target organisms.