Use of Semiochemicals for the Management of the Redbay Ambrosia Beetle

Abstract

This review highlights current advances in the management of the redbay ambrosia beetle, Xyleborus glabratus, a primary vector of the pathogenic fungus, Raffaelea lauricola, that causes laurel wilt. Laurel wilt has a detrimental effect on forest ecosystems of southeastern USA, with hundreds of millions of Lauraceae deaths. Currently, preventive measures mostly focus on infected-tree removal to potentially reduce local beetle populations and/or use of preventative fungicide applications in urban trees. Use of semiochemicals may offer an opportunity for the management of X. glabratus. Research on attractants has led to the development of α-copaene lures that are now the accepted standards for X. glabratus sampling. Research conducted on repellents first included methyl salicylate and verbenone and attained significant reduction in the number of X. glabratus captured on redbay and swamp bay trees treated with verbenone. However, the death rate of trees protected with verbenone, while lower compared to untreated trees, is still high. This work underscores the necessity of developing new control methods, including the integration of repellents and attractants into a single push-pull system.