title: North American Lauraceae: terpenoid emissions, relative attraction and boring preferences of redbay ambrosia beetle, Xyleborus glabratus (coleoptera: curculionidae: scolytinae).
abstract: The invasive redbay ambrosia beetle, Xyleborus glabratus, is the primary vector of Raffaelea lauricola, a symbiotic fungus and the etiologic agent of laurel wilt. This lethal disease has caused severe mortality of redbay (Persea borbonia) and swampbay (P. palustris) trees in the southeastern USA, threatens avocado (P. americana) production in Florida, and has potential to impact additional New World species. To date, all North American hosts of X. glabratus and suscepts of laurel wilt are members of the family Lauraceae. This comparative study combined field tests and laboratory bioassays to evaluate attraction and boring preferences of female X. glabratus using freshly-cut bolts from nine species of Lauraceae: avocado (one cultivar of each botanical race), redbay, swampbay, silkbay (Persea humilis), California bay laurel (Umbellularia californica), sassafras (Sassafras albidum), northern spicebush (Lindera benzoin), camphor tree (Cinnamomum camphora), and lancewood (Nectandra coriacea). In addition, volatile collections and gas chromatography-mass spectroscopy (GC-MS) were conducted to quantify terpenoid emissions from test bolts, and electroantennography (EAG) was performed to measure olfactory responses of X. glabratus to terpenoids identified by GC-MS. Significant differences were observed among treatments in both field and laboratory tests. Silkbay and camphor tree attracted the highest numbers of the beetle in the field, and lancewood and spicebush the lowest, whereas boring activity was greatest on silkbay, bay laurel, swampbay, and redbay, and lowest on lancewood, spicebush, and camphor tree. The Guatemalan cultivar of avocado was more attractive than those of the other races, but boring response among the three was equivalent. The results suggest that camphor tree may contain a chemical deterrent to boring, and that different cues are associated with host location and host acceptance. Emissions of α-cubebene, α-copaene, α-humulene, and calamenene were positively correlated with attraction, and EAG analyses confirmed chemoreception of terpenoids by antennal receptors of X. glabratus.
authors.affiliation: United States Department of Agriculture, Agricultural Research Service, Subtropical Horticulture Research Station, Miami, Florida, United States of America.
authors.forename: Paul E
authors.initials: PE
authors.lastname: Kendra
authors.affiliation: United States Department of Agriculture, Agricultural Research Service, Subtropical Horticulture Research Station, Miami, Florida, United States of America.
authors.forename: Wayne S
authors.initials: WS
authors.lastname: Montgomery
authors.affiliation: United States Department of Agriculture, Agricultural Research Service, Subtropical Horticulture Research Station, Miami, Florida, United States of America.
authors.forename: Jerome
authors.initials: J
authors.lastname: Niogret
authors.affiliation: Archbold Biological Station, Lake Placid, Florida, United States of America.
authors.forename: Grechen E
authors.initials: GE
authors.lastname: Pruett
authors.affiliation: United States Department of Agriculture, Forest Service, Southern Research Station, Asheville, North Carolina, United States of America.
authors.forename: Albert E
authors.initials: AE
authors.lastname: Mayfield
authors.affiliation: United States Department of Agriculture, Forest Service, Forest Health Protection, Stanislaus National Forest, Sonora, California, United States of America.
authors.forename: Martin
authors.initials: M
authors.lastname: MacKenzie
authors.affiliation: Archbold Biological Station, Lake Placid, Florida, United States of America.
authors.forename: Mark A
authors.initials: MA
authors.lastname: Deyrup
authors.affiliation: United States Department of Agriculture, Agricultural Research Service, Beltsville Area Research Center, Electron and Confocal Microscopy Unit, Beltsville, Maryland, United States of America.
authors.forename: Gary R
authors.initials: GR
authors.lastname: Bauchan
authors.affiliation: University of Florida, Tropical Research and Education Center, Homestead, Florida, United States of America.
authors.forename: Randy C
authors.initials: RC
authors.lastname: Ploetz
authors.affiliation: United States Department of Agriculture, Agricultural Research Service, Subtropical Horticulture Research Station, Miami, Florida, United States of America.
authors.forename: Nancy D
authors.initials: ND
authors.lastname: Epsky
mesh_terms: D000818:Animals; D005260:Female; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods; D019770:Lauraceae / Q000737:chemistry* / Q000145:classification / Q000469:parasitology*; D010675:Pheromones / Q000302:isolation & purification; D010936:Plant Extracts / Q000737:chemistry; D012903:Smell; D013729:Terpenes / Q000302:isolation & purification*; D014481:United States; D048889:Weevils / Q000502:physiology*
chemical_list: D010675:Pheromones; D010936:Plant Extracts; D013729:Terpenes