Flea beetle (Coleoptera: Chrysomelidae) response to alkyl thiocyanates and alkyl isothiocyanates
¹Estonian Agricultural University, Kreutzwaldi 1, 51014 Tartu, Estonia
²The Royal Institute of Technology, Sweden, Dept of Chemistry, Organic Chemistry, Ecological Chemistry, KTH, S-100 44 Stockholm, Sweden
The attractivity of nine compounds, allyl isothiocyanate (allyl IT), benzyl isothiocyanate (benzyl ITC), 3-butenyl isothiocyanate (butenyl ITC), 3-butenyl thiocyanate (butenyl TC), butyl isothiocyanate (butyl ITC), butyl thiocyanate (butyl TC), 2-phenylethan-1-yl isothiocyanate (phenetyl ITC), 2-phenyleth-1-yl thiocyanate (phenetyl TC), and 2-phenylethan-1-ol, was compared to the beetle genera Phyllotreta species. Field tests were performed on fields of wild crucifer plants and on the edge of an oilseed rape field. Test places were at Juuru in Northern Estonia, at Valgeristi in the middle of Estonia and at Matsi in Southern Estonia. In our tests, Phyllotreta spp were most attracted to butenyl TC and butenyl ITC; allyl ITC and other tested alkyl-TC, alkyl-ITC, aryl-TC and aryl-ITC had lower attractivity. Cylindrical traps with a large clued area were tested and are recommended for practical usage, capillary polyethylene dispensers are recommended instead of sachet type dispensers. Emission of substances from sachet dispensers is described in the article.