Laboratory release rate studies of Shin‐Etsu, freshly manufactured versus cold‐stored, fresh pheromone ropes

Abstract

The release rates of freshly manufactured and cold‐stored, fresh Shin‐Etsu diamondback moth pheromone ropes were studied. These rates were identical at 50°C 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‐l‐ol acetate reside entirely in the wall of the ropes for each lot and none in the wens. 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 50°C 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‐l‐ol acetate of the theoretical amount in the total rope for 69025 and 0.1% Z‐7‐dodecen‐l‐ol acetate, 1.1% Z‐11‐hexadecenal, and 3.5% Z‐11‐hexadecen‐l‐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.

Key words:

• Pheromone ropes
• diamondback moth
• cabbage looper
• gravimetric analysis
• GC analysis