Biosafety of Deltamethrin Sublethal Doses for Honeybee A. Mellifera L. in Iraq

Abstract

This study has been conducted in the faculty of Agriculture-University of Kufa from March-November 2021. The main objectives of the current study are to determine the deltamethrin residues in honey samples collected from 5 regions of Najaf, middle of Iraq, and to investigate the effect of sublethal doses of deltamethrin on honeybee survival. The results of the current study showed that the residues were 10.6, 8.6 and 7.7 ppm in sample 1,3 and 4 respectively. However, deltamethrin residues from another area (sample 2 and 5) were not detected. In forager bees, the high rate of food consumption of 1M sucrose containing deltamethrin at different concentrations was 86.7 µl/bee/day at 0.25ppm compared to 69 µl/bee/day in control. Whereas, the maximum food consumption for nurse bees was 58.2 µl/bee/day compared to 39-43 µl/bee/day at 1-100 ppm. Bee survival ranged between 93-96% in nurse bees and 70-83% in foragers at 0.25-100ppm deltamethrin. It can be concluded that the sublethal doses of deltamethrin on honeybee survival was low and can be used against insect pests after testing them in the laboratory and field.