title: Infectivity of Steinernema carpocapsae and S. feltiae to Larvae and Adults of the Hazelnut Weevil, Curculio nucum: Differential Virulence and Entry Routes.
abstract: We investigated the existing susceptibility differences of the hazelnut weevil, Curculio nucum L. (Coleoptera:, Curculionidae) to entomopathogenic nematodes by assessing the main route of entry of the nematodes, Steinernema carpocapsae strain B14 and S. feltiae strain D114, into larvae and adult insects, as well as host immune response. Our results suggested that S. carpocapsae B14 and S. feltiae D114 primarily entered adult insects and larvae through the anus. Larvae were more susceptible to S. feltiae D114 than S. carpocapsae B14 and adults were highly susceptible to S. carpocapsae B14 but displayed low susceptibility to S. feltiae D114. Penetration rate correlated with nematode virulence. We observed little evidence that hazelnut weevils mounted any cellular immune response toward S. carpocapsae B14 or S. feltiae D114. We conclude the differential susceptibility of hazelnut weevil larvae and adults to S. carpocapsae B14 and S. feltiae D114 primarily reflected differences in the ability of these two nematodes to penetrate the host.
authors.affiliation: Departament Biologia Animal, Vegetal i Ecologia. Facultat de Biociències, Universitat Autònoma de Barcelona, Bellaterra, E-08193 Barcelona, Spain.
authors.forename: Laia
authors.initials: L
authors.lastname: Batalla-Carrera
authors.affiliation: Departament Biologia Animal, Vegetal i Ecologia. Facultat de Biociències, Universitat Autònoma de Barcelona, Bellaterra, E-08193 Barcelona, Spain.
authors.forename: Ana
authors.initials: A
authors.lastname: Morton
authors.affiliation: USDA-ARS, Southeastern Fruit and Tree Nut Research Laboratory, 21 Dunbar Rd., Byron, GA 31008.
authors.forename: David
authors.initials: D
authors.lastname: Shapiro-Ilan
authors.affiliation: Department of Entomology, University of Georgia, Athens, GA.
authors.forename: Michael R
authors.initials: MR
authors.lastname: Strand
authors.affiliation: Departament Biologia Animal, Vegetal i Ecologia. Facultat de Biociències, Universitat Autònoma de Barcelona, Bellaterra, E-08193 Barcelona, Spain.
authors.forename: Fernando
authors.initials: F
authors.lastname: García-Del-Pino
keywords: Curculionidae; Steinernema carpocapsae; Steinernema feltiae; entry routes; immune response; penetration rate