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Laurel wilt and Fusarium dieback are vascular diseases caused by fungal symbionts of invasive ambrosia beetles (Coleoptera: Curculionidae: Scolytinae). Both diseases threaten avocado trees in Florida. Redbay ambrosia beetle, Xyleborus glabratus , is the primary vector of the laurel wilt pathogen, Raffaelea lauricola , but in recent years this symbiont has been transferred laterally to at least nine other species of ambrosia beetle, which now comprise a community of secondary vectors. Dieback disease, caused by Fusarium spp. fungi, is spread by shot hole borers in the Euwallacea fornicatus species complex. In this study, we conducted field tests in Florida avocado groves to compare efficacy of four trap designs for detection of Scolytinae. Treatments included an 8-funnel Lindgren trap, black 3-vane flight interception trap, green 3-vane interception trap, white sticky panel trap, and an unbaited sticky panel (control). In two tests targeting E. nr. fornicatus and X. glabratus , traps were baited with a two-component lure (α-copaene and quercivorol). In a test targeting other species, traps were baited with a low-release ethanol lure. For E. nr. fornicatus, sticky panels and black interception traps captured significantly more beetles than Lindgren traps; captures with green traps were intermediate. With ethanol-baited traps, 20 species of bark/ambrosia beetle were detected. Trap efficacy varied by species, but in general, sticky traps captured the highest number of beetles. Results indicate that sticky panel traps are more effective for monitoring ambrosia beetles than Lindgren funnel traps, the current standard, and may provide an economical alternative for pest detection in avocado groves. [ABSTRACT FROM AUTHOR]

The invasive redbay ambrosia beetle, Xyleborus glabratus Eichhoff (Coleoptera: Curculionidae: Scolytinae), vectors the fungal pathogen (Raffaelea lauricola) that causes laurel wilt, a disease responsible for widespread mortality of trees in the Lauraceae in the southeastern United States. Early detection of incipient vector populations may allow for management practices that could successfully mitigate damage. Developing new, highly effective attractants is a priority for improving sensitivity of early detection efforts. In this study, two field tests were conducted to evaluate combinations of commercially available bark and ambrosia beetle lures for enhanced attraction of host-seeking female X. glabratus. In addition, lures were compared for capture of nontarget scolytine beetles. In the first experiment, traps baited with a combination of cubeb oil, conophthorin, chalcogran, and ethanol captured greater numbers of X. glabratus than cubeb oil alone, the current standard attractant. However, this combination lure resulted in higher nontarget scolytine captures than with the cubeb lure. In the second field test, an oil enriched in the sesquiterpene α-copaene caught significantly more X. glabratus than other lures currently available for monitoring this pest. There were no differences in efficacy between cubeb oil lures produced by two different manufacturers, and a combination lure containing copaiba and cubeb oils did not increase captures over the cubeb lure alone. Results of these two tests suggest that increased sensitivity for detection of X. glabratus may be achieved with a multicomponent lure that incorporates α-copaene, spiroketals, and low release of ethanol. [ABSTRACT FROM AUTHOR]