Toxicity of different insecticides against the dwarf honey bee, Apis florea Fabricius (Hymenoptera: Apidae)

Abstract

Honey bees are considered as critical beneficial insects in the term of honey production and pollination of crops. One of the essential honey bee species in Pakistan is Apis florea Fabricius (Hymenoptera: Apidae). These make nests on trees near human dwellings and agriculture crops. During foraging in the field for nectar and pollen collection from agriculture flowering plants, honey bees may be exposed to pesticide sprays which may cause a change in their foraging behavior and the death of their workers. The current study evaluates the toxicity of six insecticides (emamectin benzoate, spinetoram, chlorantraniliprole, fipronil, flonicamid, and imidacloprid) against workers of A. florea. There were six concentrations of each insecticide (causing > 0% to < 100 % mortality) prepared in water, and each concentration was replicated four times. The experiment was conducted using the diet incorporation method in a plastic container. Emamectin benzoate was found the most toxic insecticide with lower LC50 values (1.02 µg/mL) followed by spinetoram (1.10 µg/mL), chlorantraniliprole (2.74 µg/mL), imidacloprid (3.09 µg/mL), flonicamid (3.94 µg/mL), fipronil (6.00 µg/mL) after 48 h of exposure. The results showed that insecticides are very toxic to A. florea and should be used on agriculture crops with great care and during less activity.