Molecular identification of scarab-larvae predators

Cockchafers, Summer- and Garden-Chafers (Coleoptera: Scarabaeidae) are the most abundant scarab-species in Central-Europe. Due to their root feeding activity in the larval stage, they can strongly influence the floral and faunal community of a site. White grubs often cause severe damage in grasslands and different field crops. Chemical control is restricted because of its often low efficiency and environmental hazards. Biological control methods (fungi, nematodes) can show detrimental side effects on beneficial non-target organisms. Insect predators are known to have considerable impact on white grub populations but up to now the predatory guild of the three most common scarab-species of Europe has not been investigated. The aim of the present project to identify natural enemies of white grubs (e.g. raptorial ground beetles, rove beetles). In a further step, we will estimate which of the identified predators will be potentially key-elements for the regulation of scarab larvae. The findings of the present project will finally contribute to the development of more efficient and ecological control strategies. White grub predators will be identified by specific DNA-sequences, which can be found in the gut of the predators after consumption of scarab larvae. We will use a new molecular approach, which will enable us to screen predators simultaneously for several prey species. Our methodology will also be of importance for future studies dealing with trophic relationships in different ecosystems. This will provide an important step forward in applied and basic ecosystem-research.