Biological Control of Scarabs with Entomopathogenic Nematodes

White grubs, the larvae of scarab beetles, are serious pests of turf, pastures, sugar cane, and horticultural crops throughout the world. Several nematode species (Steinernema glaseri, S. anomali, S. kushidai, and Heterorhabditis megidis) and strains of S. carpocapsae and H. bacteriophora have been isolated from white grubs, indicating their potential to control scarab larvae. Early efforts to use S. glaseri against the Japanese beetle failed, possibly due to a lack of appreciation for the nematode-bacterium complex. More recently, field efficacy with S. glaseri and H. bacteriophora has been demonstrated against a variety of white grubs. However, before reliable results can be expected, more information on overcoming host defence mechanisms is essential, application techniques which allow nematodes to reach target pests must be developed, and the effects of biotic and abiotic factors on nematode survival in the soil environment require elucidation. Prospects are increasing for the utilisation of entomopathogenic nematodes as either inoculative or inundative agents for suppression of scarab larvae.