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

Unmated adult female Colorado potato beetles, Leptinotarsa decemlineata (Sa y), were attracted to damaged and chemically treated potato plants in an ol factometer. Significantly more beetles moved upwind to potato plants with d amage from larval Colorado potato beetle compared with undamaged plants. Mo re beetles moved upwind toward potato plants treated with regurgitant from Colorado potato beetle larvae or cabbage looper larvae, Trichoplusia ni (Hu bner), compared with undamaged plants. Greater numbers of beetles moved upw ind toward potato plants treated with N-(17-hydroxylinolenoyl)-L-glutamine (volicitin) or to plants treated with the plant hormone methyl jasmonate, c ompared 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 res ponse to stimuli from feeding larvae enhance the attractiveness of the plan t to female Colorado potato beetles.