title: Using plant chemistry and insect preference to study the potential of Barbarea (Brassicaceae) as a dead-end trap crop for diamondback moth (Lepidoptera: Plutellidae).
abstract: Barbarea vulgaris R. Br. has been proposed as a dead-end trap crop for diamondback moth, Plutella xylostella L. (Lepidoptera: Plutellidae), because its larvae do not survive on this plant species despite being highly preferred for oviposition. We compared plants of several species, varieties, and types in the genus Barbarea (Brassicaceae) to study their potential as trap crops for P. xylostella. In terms of insect behavior, Barbarea plants were assessed based on the criteria of high oviposition preference by P. xylostella moths (compared to other Barbarea plants and to three Brassica oleracea L. crop varieties) and low survival of P. xylostella larvae. Barbarea plants were also assessed based on the criteria of high content of glucosinolates, which stimulate adult oviposition and larval feeding in P. xylostella, and high content of saponins, which are detrimental to survival of P. xylostella larvae. All Barbarea plants tested were preferred over cabbage by ovipositing P. xylostella. Among Barbarea plants, few significant differences in oviposition preference by P. xylostella were found. Ovipositing P. xylostella preferred B. vulgaris plants containing mainly 2-phenylethylglucosinolate over B. vulgaris plants containing mainly (S)-2-hydroxy-2-phenylethylglucosinolate, and P-type B. vulgaris var. arcuata plants over Barbarea rupicola and B. vulgaris var. variegata plants. Despite containing a lower content of saponins than other Barbarea plants tested, Barbarea verna did not allow survival of P. xylostella larvae. Our studies show that, except for B. rupicola and P-type B. vulgaris var. arcuata, which allowed survival of P. xylostella larvae, all Barbarea plants tested have potential as dead-end trap crops for P. xylostella.
authors.affiliation: Max Planck Institute for Chemical Ecology, Department of Entomology, 07745 Jena, Germany; Instituto de Ciencias Agrarias, Consejo Superior de Investigaciones Científicas, 28006 Madrid, Spain. Electronic address: frbadenes@ica.csic.es.
authors.forename: Francisco R
authors.initials: FR
authors.lastname: Badenes-Perez
authors.affiliation: Max Planck Institute for Chemical Ecology, Department of Biochemistry, 07745 Jena, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Reichelt
authors.affiliation: Max Planck Institute for Chemical Ecology, Department of Biochemistry, 07745 Jena, Germany.
authors.forename: Jonathan
authors.initials: J
authors.lastname: Gershenzon
authors.affiliation: Instituto de Ciencias Agrarias, Consejo Superior de Investigaciones Científicas, 28006 Madrid, Spain.
authors.forename: David G
authors.initials: DG
authors.lastname: Heckel
mesh_terms: D000818:Animals; D019607:Brassicaceae / Q000737:chemistry* / Q000235:genetics / Q000254:growth & development; D005961:Glucosinolates / Q000032:analysis; D007915:Lepidoptera / Q000737:chemistry*; D012503:Saponins / Q000032:analysis
chemical_list: D005961:Glucosinolates; D012503:Saponins
keywords: Barbarea spp.; Brassicaceae; Feeding deterrent; Glucosinolates; Host plant resistance; Oviposition preference; Plutella xylostella; Saponins; Trap crop