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Redbay ambrosia beetle Xyleborus glabratus is an invasive wood boring beetle that has become established in the southeastern U. S.A. and transmits a fungus Raffaelea lauricola that causes lethal laurel wilt. Among susceptible Lauraceae hosts are redbay Persea borbonia and avocado Persea americana., There is a crucial need for detection of this pest as it moves into new areas. Consequently, our goal was to create a better lure for the monitoring and control of redbay ambrosia beetle., We analyzed volatile emissions of R. lauricola, created a synthetic odour blend based on this analysis and tested this odour blend as a potential attractant in a redbay forest infested with X. glabratus. The synthetic Raffaelea odour blend was not attractive to the beetles by itself. However, it synergistically increased attraction to host-mimic volatiles., We tested four commercial release devices for dispensing Raffaelea odour at various release rates. Two prototypes with the highest release rate, when paired with commercial manuka oil lures, captured more beetles than manuka oil lures alone. These results indicate that a synthetic blend of volatiles based on the odour of the symbiotic fungus of X. glabratus may be useful for the development of more sensitive monitoring lures for this invasive pathogen vector. [ABSTRACT FROM AUTHOR]

The exotic redbay ambrosia beetle, Xyleborus glabratus Eichhoff (Coleoptera: Curculionidae: Scolytinae), and its fungal symbiont Raffaellea lauricola Harrington, Fraedrich, and Aghayeva are responsible for widespread redbay, Persea borbonia (L.) Spreng., mortality in the southern United States. Effective traps and lures are needed to monitor spread of the beetle and for early detection at ports-of-entry, so we conducted a series of experiments to find the best trap design, color, lure, and trap position for detection of X. giabratus. The best trap and lure combination was then tested at seven sites varying in beetle abundance and at one site throughout the year to see how season and beetle population affected performance. Manuka oil proved to be the most effective lure tested, particularly when considering cost and availability. Traps baited with manuka oil lures releasing 5 mg/d caught as many beetles as those baited with lures releasing 200 mg/d. Distributing manuka oil lures from the top to the bottom of eight-unit funnel traps resulted in similar numbers of X. glabratus as a single lure in the middle. Trap color had little effect on captures in sticky traps or cross-vane traps. Funnel traps caught twice as many beetles as cross-vane traps and three times as many as sticky traps but mean catch per trap was not significantly different. When comparing height, traps 1.5 m above the ground captured 85% of the beetles collected but a few were caught at each height up to 15 m. Funnel trap captures exhibited a strong linear relationship r2 = 0.79) with X. glabratus attack density and they performed well throughout the year. Catching beetles at low densities is important to port of entry monitoring programs where early detection of infestations is essential. Our trials show that multiple funnel traps baited with a single manuka oil lure were effective for capturing X. glabratus even when no infested trees were visible in the area. [ABSTRACT FROM AUTHOR]

The article discusses research aimed at minimizing the threat posed by the redbay ambrosia beetle to avocado. It references a study by entomologist Paul Kendra and his colleagues at the U.S. Agricultural Research Service's (ARS) Subtropical Horticulture Research Station (SHRS) in Miami, Florida, published in the "Journal of Chemical Ecology." The team used manuka and phoebe tree oils in traps to monitor the beetle's movement in Florida.