title: A novel attractant for Mexican fruit fly,Anastrepha ludens, from fermented host fruit.
abstract: Chemicals from fermented chapote fruit were identified and evaluated as attractants for hungry adult Mexican fruit flies in laboratory and greenhouse bioassays. Twenty-eight chemicals identified from an attractive gas-chromatography fraction were as attractive as a chapote volatiles extract (CV) when mixed in the same amounts found in CV. Sixteen of the chemicals were slightly attractive to flies when tested individually. A mixture containing 15 of the chemicals by design and the 16th as an impurity, in arbitrary concentrations, was at least as attractive as the original CV. In a series of experiments, the number of chemicals was reduced to three by elimination of unnecessary components. The three-component mixture retained the attractiveness of the 15-component mixture. The three chemicals were 1,8-cineole, ethyl hexanoate, and hexanol (CEH). Attractiveness of the three-chemical mixture was equal to the sum of the attractiveness of the three individual components, suggesting that each chemical binds to a different receptor type that independently elicits partial attraction behavior. Optimal ratios were 10∶1∶1 of the three chemicals, respectively. Optimal test quantities ranged between 0.4-4Μg of 1,8-cineole and 40-400 ng each of ethyl hexanoate and hexanol applied to filter paper in the laboratory bioassays. A neat 10∶1∶1 mixture of the chemicals was 1.8 times more attractive than aqueous solutions ofTorula dried yeast and borax to starved 2-day-old flies when the lures were tested in competing McPhail traps in a large greenhouse cage.
authors.affiliation: Crop Quality and Fruit Insects Research, ARS, USDA, 2301 South International Blvd., 78596, Weslaco, Texas.
authors.forename: D C
authors.initials: DC
authors.lastname: Robacker
authors.forename: A M
authors.initials: AM
authors.lastname: Moreno
authors.forename: J A
authors.initials: JA
authors.lastname: Garcia
authors.forename: R A
authors.initials: RA
authors.lastname: Flath