Assessment of establishment and persistence of entomopathogenic nematodes for biological control of western corn rootworm

The use of entomopathogenic nematodes (EPN) is potentially one ecological approach to control the invasive alien western corn rootworm (Diabrotica virgifera virgifera LeConte, Col., Chrysomelidae) in Europe. This study investigated the establishment and the short- and long-term persistence of Heterorhabditis bacteriophora Poinar (Rhabditida: Heterorhabditidae), Heterorhabditis megidis Poinar, Jackson and Klein (Rh., Heterorhabditidae) and Steinernema feltiae Filipjev (Rh., Steinernematidae) in three maize fields in southern Hungary, using the insect-baiting technique. All three EPN species equally established and persisted in maize fields. The timing of application (April or June) did not influence the establishment of EPN species. EPNs persisted for 2-5 months, i.e. they survived up to and throughout D. v. virgifera larval occurrence in the soil. Results demonstrate that D. v. virgifera larvae can potentially be controlled by EPNs during the same year of EPN application but no long-term control effect is expected under intensive maize cultivation practices.