Attraction of colorado potato beetle (Coleoptera: Chrysomelidae) to damaged and chemically induced potato plants

Unmated adult female Colorado potato beetles, Leptinotarsa decemlineata (Say), were attracted to damaged and chemically treated potato plants in an olfactometer. Significantly more beetles moved upwind to potato plants with damage from larval Colorado potato beetle compared with undamaged plants. More beetles moved upwind toward potato plants treated with regurgitant from Colorado potato beetle larvae or cabbage looper larvae, Trichoplusia ni (Hubner), compared with undamaged plants. Greater numbers of beetles moved upwind toward potato plants treated with N-(17-hydroxylinolenoyl)-L-glutamine (volicitin) or to plants treated with the plant hormone methyl jasmonate, compared with untreated plants. Mechanical injury to potato foliage did not increase beetle attraction when plants were tested 1 or 24 h after injury. These results indicate that volatile chemicals produced by the plant in response to stimuli from feeding larvae enhance the attractiveness of the plant to female Colorado potato beetles.