Submitted to: Phytochemical Society of North America Meeting and Newsletter
Publication Type: Abstract Only
Publication Acceptance Date: 8/13/2003
Publication Date: 8/13/2003
Citation: Johnson, E.T., Dowd, P.F. 2003. Plant Anthocyanin Insect Feeding Deterrents [abstract]. Phytochemical Society of North America. Abstract Neish Symposia 10.
Technical Abstract: The anthocyanins are synthesized by flowers primarily to attract pollinators and seed dispersers. A few studies have determined that some anthocyanin compounds can reduce insect feeding. Of several anthocyanins tested, we found that delphinidin-3-O-glucoside added to insect diet at 1000 ppm significantly inhibited the growth of fall armyworms and cabbage loopers while cyanidin-3-O-glucoside only reduced the growth of fall armyworms. We also fed cabbage looper larvae leaves of an Arabidopsis thaliana transgenic mutant that accumulates cyanidin-3-O-glucosides. Leaves of the wild type control were more heavily damaged than the cyanidin-accumulating leaves. Lastly, we conducted insect feeding studies on floral tissues of Petunia hybrida, which can synthesize large amounts of different anthocyanins depending on the variety. Mortality rates of corn earworm and cabbage looper larvae were the highest on a lightly colored petunia flower that accumulates a precursor to the visible anthocyanin pigments. Together these results indicate that expression of relevant anthocyanin molecules at suitable levels may be an effective means to reduce insect predation of plant tissues.