Abstract

When an herbivorous insect enters a new geographic area, it will select host plants based on short and long distance cues. A conifer-feeding bark beetle that has been recently introduced to North America, the Mediterranean pine engraver, Orthotomicus erosus (Wollaston), has a potentially wide host range, especially among members of the Pinaceae. The long-distance response of the beetles to tree odors may be a key feature of the mechanism of host recognition and selection. We used a laboratory olfactometer to study the walking response of 1,440 O. erosus to odor cues from the bark and phloem of six North American tree species. The beetle moved toward the angiosperm non-host Betula papyrifera more than would be expected by chance, but had a neutral response to odors of two tree species that support reproduction and three species that do not. These results suggest that tree odors alone may not be adequate for O. erosus to recognize novel hosts.

Keywords

Bark beetle; host range testing; Pinaceae; Scolytidae; sequential no-choice olfactometer; balsamfir; Abies balsamea; eastern hemlock; Tsuga canadensis; paper birch; Betula papyrifera; red pine; Pinus resinosa; tamarack; Larix laricina; white spruce; Picea glauca

Published in

Journal of Insect Behavior
2010, volume: 23, number: 4, pages: 251-267
Publisher: SPRINGER/PLENUM PUBLISHERS

Authors' information