Host tree resistance against the polyphagous wood-boring beetle Anoplophora glabripennis

Anoplophora gbbriperznis (Motschulsky) (Coleoptera: Cerambycidae: Lamiini) is an invasive woodboring beetle with an unusually broad host range and a proven ability to increase its host range as it colonizes new areas and encounters new tree species. The beetle is native to eastern Asia and has become an invasive pest in North America and Europe, stimulating interest in delineating host and non-host tree species more clearly. When offered a choice among four species of living trees in a greenhouse, adult A. glabripennis fed more on golden-rain tree (Koelreuteria paniculata Laxmann) and river birch (Betub nigra L.) than on London planetree (Platanus x acerifolia (Aiton) Willdenow) or callery pear (Pyrus calleryana Decaisne). Oviposition rate was highest in golden-rain tree, but larval mortality was also high and larval growth was slowest in this tree species. Oviposition rate was lowest in callery pear, and larvae failed to survive in this tree species, whether they eclosed from eggs laid in the treg or were manually inserted into the trees. Adult beetles feeding on c&ery pear had a reduced longevity and females feeding only on callery pear failed to develop any eggs. The resistance of golden-rain tree against the larvae appears to operate primarily through the physical mechanism of abundant sap flow. The resistance of callery pear against both larvae and adults appears to operate through the chemical composition of the tree, which may include compounds that are toxic or which otherwise interfere with normal growth and development of the beetle. Unlike river birch or London planetree, both golden-rain tree and callery pear are present in the native range of A. glabripennis and may therefore have developed resistance to the beetle by virtue of exposure to attack during their evolutionary history.