Tuesday, December 11, 2007
D0357

Non-target effects of imidacloprid in nectar on the monarch butterfly, Danaus plexippus, and the painted lady butterfly, Vanessa cardui

Mary Rogers, roge0168@umn.edu and Vera Aber Krischik, krisc001@umn.edu. University of Minnesota, 1980 Folwell Ave. #219, St. Paul, MN

Two species of nymphalid butterflies, the monarch (Danaus plexippus), and painted lady (Vanessa cardui), were exposed to plants treated with 1X and 2X soil applications of Marathon (1% imidacloprid). Residue analysis quantified the presence of imidacloprid in nectar of a single flower: 3 ppb in controls, 29 ppb in 1X, and 54 ppb in 2X plants. Adult survivorship or fecundity was not reduced, but larval survivorship was reduced on imidacloprid-treated Asclepias curassavica. It is important to understand if greenhouse grown plants that are treated with imidacloprid for pests contain residues that affect foraging adult butterflies and caterpillars.


Species 1: Lepidoptera Danaidae Danaus plexippus (monarch butterfly)
Species 2: Lepidoptera Nymphalidae Vanessa cardui (painted lady butterfly)