Predators and Parasitoids Associated with Scolytinae in Persea Species (Laurales: Lauraceae) and Other Lauraceae in Florida and Taiwan

Abstract The redbay ambrosia beetle, Xyleborus glabratus Eichhoff (Coleoptera: Curculionidae: Scolytinae), due to its association with Raffaelea lauricola T.C. Harr., Fraedrich & Aghayeva (Ophiostomatales: Ophiostomataceae), a pathogen that causes laurel wilt, is considered one of the most damaging pests of Persea species (Laurales: Lauraceae) including avocado. Currently, there is no satisfactory method to control this pest. Biological control is being examined as an additional tool to be used to lower the pest population and slow its spread. The objective of this study was to determine the natural enemy community associated with X. glabratus in Florida and Taiwan by using 3 methods: 1) field-collected wood naturally infested with X. glabratus (Florida), 2) bolts of avocado artificially infested with X. glabratus (Florida) and 3) direct collection of natural enemies from a trap area baited with infested wood and known X. glabratus lures (Florida and Taiwan). Among the predacious insects, there were 8 species of Laemophloeidae, an unidentified species of Staphylinidae, Microsicus spp. (Zopheridae), and Europs sp. (Monotomidae) (all Coleoptera). Among the parasitoids, hymenopterans of the families Braconidae, Eulophidae, Pteromalidae, Encyrtidae, Eupelmidae, and Bethylidae emerged from wood containing various species of Scolytinae. However, the only specimens that emerged from logs in which X. glabratus was present were Bethylidae, Braconidae, Encyrtidae (perhaps Closterocerus sp.), and Scelionidae. Four hymenopteran species were collected using attractants in Florida and Taiwan. However, more studies are needed to clarify their role as natural enemies of X. glabratus.