Rapid measure of sex pheromone emission from plastic rope dispensers: Example of utility in sexual communication disruption of the diamondback moth,Plutella xylostella1

An easy and reliable method to measure the emissions from plastic dispensers, which is adaptable to other dispensers and substrates, is reported. A small bed of the adsorbent Super-Q7® was found to adsorb large quantities of all of the sex pheromone components tested and, concomitantly, to enable enough air flow to approximate air speeds over the dispensers that may be encountered in nature. Some of the advantages of this method over others are its ease of use and accuracy and the direct measures of emissions.E.g. measurements showed that Z11-16:A1, one of the constituents of a rope lot, was emitted at a rate inconsistent with evaporative processes; rather, it was indicative of degradation processes. Brief reference is made of the utility of the timely measurements of emission rates in field experiments to control the diamondback moth,Plutella xylostella (L.) (Lepidoptera: Plutellidae), in commercially grown cabbage in 1996.