Risk assessment of Hass avocado and Mexican Lauraceae for attack by redbay ambrosia beetle (Coleoptera: Curculionidae: Scolytinae)

Abstract

AbstractThe redbay ambrosia beetle,Xyleborus glabratusEichhoff (Coleoptera: Curculionidae: Scolytinae), vectors the mycopathogen that causes laurel wilt, a lethal vascular disease of trees in the Lauraceae. Since being detected in Georgia, USA in 2002, this invasive pest has become established in 11 additional states.With continued spread,X. glabratuswill likely enter Mexico. In advance of this event, this study was initiated to assess the risk posed to eight native laurels and Hass avocados, the predominant cultivar grown in Mexico.Wood bolts from each species were used in (a) field tests to determine the relative attraction of femaleX. glabratus, (b) laboratory bioassays to evaluate boring preferences, and (c) GC–MS analyses to identify host kairomones. For comparison, tests included control bolt treatments consisting of silkbay (an attractive U.S. laurel) and Simmonds avocado (a Florida cultivar susceptible to laurel wilt).Hass avocado and two native laurels (Persea schiedeanaandOcotea heribertoivel aff.) were highly attractive to females and elicited strong boring responses. These species were high in sesquiterpene hydrocarbons, including α‐copaene and α‐cubebene.Results of this study suggest thatX. glabratuscould become a serious agricultural and forest pest upon incursion into Mexico, with severe economic and ecological impacts.