Detection of Arsenophonus in Glycaspis brimblecombei (Hemiptera: Aphalaridae) populations in Brazil.

Eucalyptus is the most intensively managed tree genus in the world. Different factors, including damage by insect pests, affect its growth and productivity. Among these pests is Glycaspis brimblecombei Moore (Hemiptera: Aphalaridae), an exotic insect of Australian origin. The evolutionary success of this insect depends on symbiotic associations with microorganisms. The influence of these microorganisms on insect pests and their natural enemies is important for integrated management tactics. Within this context, this work aimed to detect Arsenophonus in populations of G. brimblecombei in Brazil. Eucalyptus branches infested with G. brimblecombei nymphs were collected in commercial eucalyptus plantations in six Brazilian states. Specimens of this pest were sampled soon after emergence and frozen for molecular analysis. The genomic DNA of G. brimblecombei adults from each population was extracted and used to detect the endosymbiont Arsenophonus by polymerase chain reaction (PCR) employing specific primers that target its 23 S rRNA gene. This endosymbiont was identified in all of the studied G. brimblecombei populations. This is the first report on the association between Arsenophonus and G. brimblecombei in Brazil.