title: Comparisons of contact chemoreception and food acceptance by larvae of polyphagous Helicoverpa armigera and oligophagous Bombyx mori.
abstract: We compared food choice and the initial response to deterrent treated diet between fifth instars of Helicoverpa armigera, a polyphagous generalist pest, and Bombyx mori, an oligophagous specialist beneficial. Bombyx mori was more behaviorally sensitive to salicin than to caffeine. The relative sensitivities were reversed for H. armigera, which was tolerant to the highest levels of salicin found in natural sources but sensitive to caffeine. A single gustatory receptor neuron (GRN) in the medial styloconic sensillum of B. mori was highly sensitive to salicin and caffeine. The styloconic sensilla of H. armigera did not respond consistently to either of the bitter compounds. Phagostimulants also were tested. Myo-inositol and sucrose were detected specifically by two GRNs located in B. mori lateral styloconic sensillum, whereas, in H. armigera, sucrose was sensed by a GRN in the lateral sensillum, and myo-inositol by a GRN in the medial sensillum. Myo-inositol responsiveness in both species occurred at or below 10(-3) mM, which is far below the naturally occurring concentration of 1 mM in plants. Larval responses to specific plant secondary compounds appear to have complex determinants that may include host range, metabolic capacity, and gustatory repertoire.
authors.affiliation: State Key Laboratory of Silkworm Genome Biology, Southwest University, Chongqing, China. huijie.zhang724@gmail.com
authors.forename: Hui-Jie
authors.initials: HJ
authors.lastname: Zhang
authors.forename: Cécile P
authors.initials: CP
authors.lastname: Faucher
authors.forename: Alisha
authors.initials: A
authors.lastname: Anderson
authors.forename: Amalia Z
authors.initials: AZ
authors.lastname: Berna
authors.forename: Stephen
authors.initials: S
authors.lastname: Trowell
authors.forename: Quan-Mei
authors.initials: QM
authors.lastname: Chen
authors.forename: Qing-You
authors.initials: QY
authors.lastname: Xia
authors.forename: Sylwester
authors.initials: S
authors.lastname: Chyb
mesh_terms: D000818:Animals; D001592:Benzyl Alcohols / Q000494:pharmacology; D012831:Bombyx / Q000254:growth & development / Q000502:physiology*; D002110:Caffeine / Q000494:pharmacology; D055724:Electrophysiological Phenomena / Q000187:drug effects; D005960:Glucosides / Q000494:pharmacology; D007294:Inositol / Q000494:pharmacology; D007814:Larva / Q000187:drug effects / Q000502:physiology; D009036:Moths / Q000254:growth & development / Q000502:physiology*; D025341:Principal Component Analysis; D011956:Receptors, Cell Surface / Q000378:metabolism; D058618:Sensilla / Q000033:anatomy & histology / Q000502:physiology; D013395:Sucrose / Q000494:pharmacology; D013649:Taste / Q000502:physiology
chemical_list: D001592:Benzyl Alcohols; D005960:Glucosides; D011956:Receptors, Cell Surface; D002110:Caffeine; C005696:salicin; D007294:Inositol; D013395:Sucrose