title: Volatiles mediating a plant-herbivore-natural enemy interaction in resistant and susceptible soybean cultivars.
abstract: Several studies have shown that herbivore-induced plant volatiles act directly on herbivores and indirectly on their natural enemies. However, little is known about the effect of herbivore damage on resistant and susceptible plant cultivars and its effect on their natural enemies. Thus, the aim of this study was to evaluate the attraction of the herbivorous pentatomid bug Euschistus heros and its egg parasitoid Telenomus podisi to two resistant and one susceptible soybean cultivars with different types of damage (herbivory, herbivory+oviposition, and oviposition). In a Y-tube olfactometer, the parasitoids were attracted to herbivory and herbivory+oviposition damaged soybean plants when compared to undamaged soybean plants for the resistant cultivars, but did not show preference for the susceptible cultivar Silvânia in any of the damage treatments. The plant volatiles emitted by oviposition-damaged plants in the three cultivars did not attract the egg parasitoid. In four-arm-olfactometer bioassays, E. heros females did not show preference for odors of damaged or undamaged soybean plants of the three cultivars studied. The Principal Response Curves (PRC) analysis showed consistent variability over time in the chemical profile of volatiles between treatments for the resistant cultivar Dowling. The compounds that most contributed to the divergence between damaged soybean plants compared to undamaged plants were (E,E)-α-farnesene, methyl salicylate, (Z)-3-hexenyl acetate, and (E)-2-octen-1-ol.
authors.affiliation: Embrapa Recursos Genéticos e Biotecnologia, Brasília, Brazil.
authors.forename: Mirian Fernandes Furtado
authors.initials: MF
authors.lastname: Michereff
authors.forename: Raúl Alberto
authors.initials: RA
authors.lastname: Laumann
authors.forename: Miguel
authors.initials: M
authors.lastname: Borges
authors.forename: Miguel
authors.initials: M
authors.lastname: Michereff-Filho
authors.forename: Ivone Rezende
authors.initials: IR
authors.lastname: Diniz
authors.forename: Austeclínio Lopes Farias
authors.initials: AL
authors.lastname: Neto
authors.forename: Maria Carolina Blassioli
authors.initials: MC
authors.lastname: Moraes
mesh_terms: D000085:Acetates / Q000378:metabolism; D000818:Animals; D001522:Behavior, Animal; D005260:Female; D006790:Host-Parasite Interactions; D006927:Hymenoptera / Q000502:physiology; D000442:Octanols / Q000378:metabolism; D010058:Oviposition / Q000502:physiology; D057078:Pentastomida / Q000502:physiology; D018515:Plant Leaves / Q000469:parasitology / Q000502:physiology; D012459:Salicylates / Q000378:metabolism; D012717:Sesquiterpenes / Q000378:metabolism; D013025:Glycine max / Q000469:parasitology / Q000502:physiology*; D013997:Time Factors
chemical_list: D000085:Acetates; D000442:Octanols; D012459:Salicylates; D012717:Sesquiterpenes; C425828:3-hexenylacetate; C062672:alpha-farnesene; C033069:methyl salicylate; C038844:1-octen-3-ol