Susceptibility of the European chafer (coleoptera: scarabaeidae) to entomopathogenic nematodes (rhabditida: steinernematidae, heterorhabditidae).
The European chafer Rhizotrogus majalis (Razoumowsky) feeds on turfgrass roots, causing major damage in the urban areas of northeastern North America. A laboratory study was conducted to determine the susceptibility of third-instar chafer larvae to four species of entomopathogenic nematodes (Steinernema glaseri, S. feltiae, S. carpocapsae, and Heterorhabditis bacteriophora). Only S. glaseri was virulent, and only at high numbers (LD(50) = 294 nematodes/larva). Prolonged contact with nematodes increased host mortality. Optimal conditions for S. glaseri with respect to soil type and soil moisture were determined. Maximum larval mortality was obtained with 7% moisture and a 50/50 mixture of chernozem and sand. These results suggest that these nematodes currently have little potential for the biological control of the European chafer in turfgrass.
Simard
L
L
Bélair
G
G
Brodeur
J
J