title: Emission of Volatile Compounds from Apple Plants Infested with Pandemis heparana Larvae, Antennal Response of Conspecific Adults, and Preliminary Field Trial.
abstract: This study investigated the volatile emission from apple (Malus x domestica Borkh., cv. Golden Delicious) foliage that was either intact, mechanically-damaged, or exposed to larval feeding by Pandemis heparana (Denis and Schiffermüller) (Lepidoptera: Tortricidae). Volatiles were collected by closed-loop-stripping-analysis and characterized by gas chromatography-mass spectrometry in three time periods: after 1 h and again 24 and 48 h later. Volatiles for all treatments also were monitored continuously over a 72-h period by the use of proton transfer reaction - time of flight-mass spectrometry (PTR-ToF-MS). In addition, the volatile samples were analyzed by gas chromatography-electroantennographic detection (GC-EAD) using male and female antennae of P. heparana. Twelve compounds were detected from intact foliage compared with 23 from mechanically-damaged, and 30 from P. heparana-infested foliage. Interestingly, six compounds were released only by P. heparana-infested foliage. The emission dynamics of many compounds measured by PTR-ToF-MS showed striking differences according to the timing of herbivory and the circadian cycle. For example, the emission of green leaf volatiles began shortly after the start of herbivory, and increased over time independently from the light-dark cycle. Conversely, the emission of terpenes and aromatic compounds showed a several-hour delay in response to herbivory, and followed a diurnal rhythm. Methanol was the only identified volatile showing a nocturnal rhythm. Consistent GC-EAD responses were found for sixteen compounds, including five aromatic ones. A field trial in Sweden demonstrated that benzyl alcohol, 2-phenylethanol, phenylacetonitrile, and indole lures placed in traps were not attractive to Pandemis spp. adults, but 2-phenylethanol and phenylacetonitrile when used in combination with acetic acid were attractive to both sexes.
authors.affiliation: Faculty of Science and Technology, Free University of Bozen-Bolzano, Piazza Università 5, 39100, Bolzano, Italy.
authors.forename: Valentino
authors.initials: V
authors.lastname: Giacomuzzi
authors.affiliation: Research and Innovation Centre, Fondazione Edmund Mach (FEM), Via E. Mach 1, 38010, San Michele all'Adige, Italy.|School of Engineering and Applied Sciences, Harvard University, 29 Oxford Street, Cambridge,, MA, 02138, USA.
authors.forename: Luca
authors.initials: L
authors.lastname: Cappellin
authors.affiliation: Research and Innovation Centre, Fondazione Edmund Mach (FEM), Via E. Mach 1, 38010, San Michele all'Adige, Italy.
authors.forename: Iuliia
authors.initials: I
authors.lastname: Khomenko
authors.affiliation: Research and Innovation Centre, Fondazione Edmund Mach (FEM), Via E. Mach 1, 38010, San Michele all'Adige, Italy.
authors.forename: Franco
authors.initials: F
authors.lastname: Biasioli
authors.affiliation: Büsgen-Institute, Department of Forest Zoology and Forest Conservation, University of Göttingen, Büsgenweg 3, 37077, Göttingen, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Schütz
authors.affiliation: Department of Plant Protection Biology, Unit of Integrated Plant Protection, Swedish University of Agricultural Science, Växtskyddsvägen 3, 230 53, Alnarp, Sweden.
authors.forename: Marco
authors.initials: M
authors.lastname: Tasin
authors.affiliation: USDA, Agricultural Research Service, 5230 Konnowac Pass Rd, Wapato, WA, 98951, USA. Alan.Knight@ARS.USDA.GOV.
authors.forename: Alan L
authors.initials: AL
authors.lastname: Knight
authors.affiliation: Faculty of Science and Technology, Free University of Bozen-Bolzano, Piazza Università 5, 39100, Bolzano, Italy.
authors.forename: Sergio
authors.initials: S
authors.lastname: Angeli
mesh_terms: D000818:Animals; D005260:Female; D008401:Gas Chromatography-Mass Spectrometry; D060434:Herbivory; D007814:Larva / Q000502:physiology; D007915:Lepidoptera / Q000502:physiology*; D008297:Male; D027845:Malus / Q000737:chemistry / Q000502:physiology*; D018515:Plant Leaves / Q000737:chemistry / Q000502:physiology; D055549:Volatile Organic Compounds / Q000032:analysis* / Q000378:metabolism
chemical_list: D055549:Volatile Organic Compounds
keywords: CLSA-GC-MS; Herbivore-induced volatiles; Lepidoptera; Malus x domestica; PTR-ToF-MS; Pandemis heparana; Tortricidae