A chemical basis for bark beetle ( Scolytus) distinction between host and non-host trees

Abstract

The bark beetle, Scolytus quadrispinosus, tolerated 5-hydroxy-1,4-nappthoquinone from a host tree, Carya ovata, that was a deterrent to feeding by Scolytus multistriatus. S. multistriatus fed as extensively on the benzene extract of C. ovata twig bark when 5-hydroxy-1,4-naphthoquinone was removed as it did on the benzene extract of its host, Ulmus americana. S. multistriatus feeding on the benzene extract of U. americana also was deterred by the addition of an extract of Quercus alba twig bark. These findings indicate that deterrency by chemicals in the bark of non-host trees is an important basis for bark beetle distinction between non-host and host tissues.