Effects of Some Entomopathogen Fungi on Apis mellifera L. and Bombus terrestris L.

Abstract

Bees are essential elements of agricultural production because of their role in pollination. However, some practices during production, especially pesticide applications have negative effects on bee life and behaviours. In order to decrease the side effects of pesticides, alternative methods, especially biological control, gained importance. In this study, effects of preparations containing; Beaveria bassiana, Verticillium lecanii and Metarhizium anisopliae var. anisopliae, and also Chlorpyrifos-ethyl for comparison, on Apis mellifera and Bombus terrestris, were investigated. Preparations were applied with two different methods; directly as food and by spraying, with concentrations recommended by the producer companies. In the first method, bees were fed with 5 ml solutions of the preparations mixed with sucrose solution and antenna, wing, leg and abdomen movements of the bees were controlled and scored 4 hours after applications. In the second method, bees were sprayed with the preparations and mortality rates were found. As a result of feeding method, entomopathogen preparations slightly affected the movement of the honey bees, while Chlorpyrifos-ethyl, almost totally inhibited their movement. Similarly, entomopathogens had no harmful effect on the movement of bombus bees, but the insecticide totally inhibited their movement. In the spraying method, the insecticide killed all the individuals of both bee species, while entomopathogens caused the death of only a few individuals.