Flight Performance of<i>Monochamus carolinensis</i>(Coleoptera: Cerambycidae) with Respect to Nematode Phoresis and Beetle Characteristics

Abstract

The pinewood nematode, Bursaphelenchus xylophilus (Steiner & Buhrer 1934) Nickle 1970, and its cerambycid beetle vector, Monochamus carolinensis (Olivier) have a commensal relationship. The nematode is transported from infested to uninfested host trees by beetle vectors. The influence of nematode load, the number of 4th-stage dispersal juveniles (JIV) carried per beetle, and the mated status of female beetles on the flight performance of M. carolinensis were investigated using a flight mill. Beetles that carried >10,000 JIV had a significantly shorter flight distance and duration than beetles carrying <10,000 JIV. Unmated females outperformed their mated counterparts on all measures of flight. In North America, pine wilt is primarily associated with exotic, ornamental pines. The limited and widely separated distribution of these trees may require a long flight by M. carolinensis to locate feeding and oviposition sites. Thus, nematode load or mated status may negatively influence the ability of a beetle to locate food and oviposition sites.