|Warthen Jr, J|
Submitted to: Journal of Environmental Science and Health
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/7/1997
Publication Date: N/A
Interpretive Summary: The use of pheromones on host crops was developed and demonstrated over 27 years ago to decrease the exposure of the environment to toxic chemicals for agricultural insect pest control. Mating disruption of the diamondback moth and cabbage looper moth had been demonstrated with pheromone rope dispensers to protect cabbage crops. However, a question arose about the pheromone content and release rates of ropes purchased in the last few years. Laboratory release rates of recently manufactured ropes and cold-stored ropes were determined and found to be similar, and two different analytical techniques showed that unexposed ropes newly purchased or cold-stored had the correct pheromone content. The impact of these findings is that a reliable product is being purchased and environmental variations must be studied to see why mating disruption with pheromone ropes varies.
Technical Abstract: The release rates of freshly manufactured and cold-stored, fresh Shin- Etsu diamondback moth pheromone ropes were studied. These rates were identical at 50oC with 100 ml/min air flow for 360+ hours. Gravimetric analyses at the end of exposure showed <1 mg of formulation in the well of the rope with 19.6 and 9.4% of the theoretical amount present in the total rope for lots 69025 and 41104, respectively. Gas chromatographic (GC) analyses showed 0.2% Z-11-hexadecenal and 0.3% Z-11-hexadecen-1- ol acetate reside entirely in the wall of the ropes for each lot and none in the wells. The release rates of freshly manufactured and cold-stored, fresh Shin-Etsu diamondback moth/cabbage looper pheromone ropes were also studied. These rates were nearly identical at 50oC and 100 ml/min air flow for 360+ hours. Gravimetric analyses at the end of exposure showed <3 mg of formulation in the well of the rope with 20.0 and 20.3% of the theoretical amount present in the total rope for lots 69024 and 5Y044, respectively. GC analyses showed <0.1 mg of any pheromone component in the well of either lot and overall 0.1% Z-7-dodecen-1-ol acetate, 2.6% Z-11 hexadecenal, and 7.0% Z-11-hexadecen-1-ol acetate of the theoretical amount in the total rope for 5Y044. Cold-storage of Shin-Etsu pheromone ropes for extended periods up to several years does not seem to be detrimental to the release of pheromonal components versus release from freshly manufactured ropes. Release rates of pheromonal components seem to be the same under laboratory conditions for freshly manufactured versus cold-stored, fresh ropes.