Oriental fruit moth pheromone component emission rates measured after collection by glass-surface adsorption

We collected and quantified both synthetic and natural Oriental fruit moth [Grapholitha molesta (Busck)] sex pheromone components in 250-ml round-bottom flasks by hexane rinsing of compounds adsorbed on the glass walls. This simple procedure collected 100% of the pheromone evaporated inside the flask and was useful for quantifying both nanogram and microgram amounts of emitted pheromone. Emission rates of (Z)-8-dodecenyl acetate from 1000, 100, and 10 μg-loaded rubber septa were 219, 12, and 1.2 ng/hr, respectively. G. molesta females emitted this component at 3.2 ng/hr, close to the emission rate from a 10 μg-loaded septum, which evokes "long-range" and "close-range" behaviors in the male. The corresponding alcohol, (Z)-8-dodecenyl alcohol, was emitted from rubber septa ca. 3 times faster than the acetate.