title: Pheromone response inhibitors of the corn stalk borer Sesamia nonagrioides. Biological evaluation and toxicology.
abstract: The behavioral activity of some trifluoromethyl ketones (TFMKs) as inhibitors of the pheromone activity of the corn stalk borer Sesamia nonagrioides (Lef.) (Lepidoptera: Noctuidae) is reported. The most closely-related analogue to the pheromone tested, (Z)-11-hexadecenyl trifluoromethyl ketone (Z11-16:TFMK), elicited a significant decrease in the number of male catches in traps baited with mixtures with the pheromone in 1:1 and 10:1 ratios in comparison to the pheromone alone. The E isomer of the analogue as well as two highly hydrated ketones, 3-octylthio-1,1,1-trifluoropropan-2-one (OTFP) and 1,1-difluoropentadecyl trifluoromethyl ketone, were inactive. Conversely, the saturated TFMKs n-dodecyl trifluoromethyl ketone and, particularly, n-hexadecyl trifluoromethyl ketone induced a synergistic effect when mixed with the synthetic pheromone in 10:1 ratio. However, in a wind tunnel these chemicals did not elicit any differential effect on flying moths attracted to a source containing a 10:1 blend of the analogue and the pheromone. In a dual choice bioassay with two dispensers, containing the pheromone alone, and mixtures of Z11-16:TFMK and the pheromone and separated 5 cm apart, males showed no particular preference for either dispenser. The ketone mixture, however, induced moths to execute erratic flights with frequent crosswind counter-turns and intersections with plume boundaries. The total number of contacts with the source were reduced when a control dispenser was paired with a dispenser containing Z11-16:TFMK and pheromone. Z11-16:TFMK and OTFP showed little toxicity on mice with a LD50 of 1 g/kg after the 6th day of treatment. For comparitive purposes, the major component of the pheromone, Z11-16:Ac, displayed a LD50 of 5 g/kg 6 days after application. Our results provide additional information about the activity of the TFMKs, which might be useful for the utilization of these chemicals in future pest control studies.
authors.affiliation: Escola Tecnica Superior Enginyeria Agrària, UdL-IRTA, Lleida, Spain. mriba@quimica.udl.es
authors.forename: M
authors.initials: M
authors.lastname: Riba
authors.forename: A
authors.initials: A
authors.lastname: Sans
authors.forename: P
authors.initials: P
authors.lastname: Bau
authors.forename: G
authors.initials: G
authors.lastname: Grolleau
authors.forename: M
authors.initials: M
authors.lastname: Renou
authors.forename: A
authors.initials: A
authors.lastname: Guerrero
mesh_terms: D000818:Animals; D001522:Behavior, Animal; D005260:Female; D005426:Flight, Animal; D007659:Ketones / Q000737:chemistry* / Q000494:pharmacology*; D008297:Male; D009036:Moths / Q000737:chemistry* / Q000502:physiology; D010675:Pheromones / Q000737:chemistry* / Q000494:pharmacology*; D014919:Wind
chemical_list: D007659:Ketones; D010675:Pheromones