Wednesday, December 13, 2006

Effectiveness of non-invasive applications of imidacloprid and dinotefuron for control of emerald ash borer

Deborah G. McCullough, mccullo6@msu.edu1, David Cappaert, cappaert@comcast.net1, Therese M. Poland, tpoland@fs.fed.us2, Phillip A. Lewis, phillip.a.lewis@aphis.usda.gov3, and John Molongoski, John.J.Molongoski@aphis.usda.gov3. (1) Michigan State University, Entomology, 243 Natural Science Bldg, Michigan State University, East Lansing, MI, (2) USDA Forest Service, North Central Research Station, 1407 S. Harrison Rd, East Lansing, MI, (3) USDA-APHIS, Bldg 1398 W. Truck Rd, Otis ANGB, MA

Emerald ash borer (EAB) adults feed on the foliage of ash (Fraxinus sp.) trees for at least two weeks before beginning oviposition. Our previous results indicated that controlling adult beetles before they lay eggs can often protect valuable ash trees in areas with established populations of EAB. We evaluated non-invasive methods of applying imidacloprid and dinotefuron to ash trees using a completely randomized block design that was replicated in four different sites. Ash trees in each block were randomly assigned to be treated with a (1) soil injection of imidacloprid (Macho 2F), (2) non-invasive bark spray of imidacloprid mixed with a bark-penetrating surfactant product (Macho 2F + Pentra), (3) non-invasive bark spray of dinotefuron mixed with the bark-penetrating surfactant (Safari + Pentra), (4) trunk injection of imidacloprid as a positive control (10% Imicide formulation in Mauget capsules), or (5) left as an untreated control. The two bark sprays were applied to the trunks of trees, from 30 cm to 1 m aboveground, using a garden sprayer. Foliage samples were collected from each tree in mid-June, early and late July and mid-August. Leaves from each sample were used for residue analysis with ELISA (imidacloprid) or MS/HPLC (dinotefuron). Other leaves (two per tree) from the June and July samples were used in bioassays to assess beetle survival and feeding over a four day period. Preliminary results from June and July indicate all insecticide treatments reduced survival and leaf consumption by beetles. In early July, 18 to 51% of beetles survived four days of exposure to leaves from treated trees compared with 90% survival of beetles exposed to leaves from untreated trees. Non-invasive methods of applying neo-nicotinoid insecticides may provide arborists and landscapers with a simple, rapid and efficient means to protect trees from EAB.

Species 1: Coleoptera Buprestidae Agrilus planipennis (emerald ash borer)