Ambrosia beetles associated with laurel wilt-affected avocado orchards in south Florida

Laurel wilt is rapidly spreading in south Florida avocado orchards. The key vector of this disease is the redbay ambrosia beetle RAB (Xyleborus glabratus). However, while RAB is easily detected infecting native Lauraceae trees, it is seldom detected in avocado orchards. Several other ‘resident’ species of ambrosia beetles appear to have become vectors of the disease in south Florida avocados, and some of these (i.e, Xyleborus ferrugineus and Xyleborus volvulus) have shown experimentally to be capable of transmitting laurel wilt to avocado. The goal of this study is to establish an efficient trapping system for ambrosia beetles in south Florida avocado orchards . The specific objectives are to evaluate commercially available lures for their ability to attract various ambrosia beetles to multifunnel traps, and to determine the seasonality of ambrosia beetles inhabiting these avocado agrosystems. Seven multifunnel traps were placed in each of eleven laurel wilt-affected avocado orchards in south Florida. Different lures and lure combinations were tested in several trials. Sixteen species of ambrosia beetles were captured in the traps. The most abundant species of ambrosia beetles were Xyleborinus saxeseni, Xyleborus affinis, Xylosandrus crassiusculus, Xyleborus volvulus, X. ferrugineus and X. bispinatus (Coleoptera: Curculionidae: Scolytinae).  The seasonality of these species and their attractiveness to multiple commercially available lures is presented.