ARS | Publication request: Evaporation rate of emulsion and oil-base emulsion pheromones

Submitted to: ASABE Annual International Meeting
Publication Type: Proceedings
Publication Acceptance Date: March 15, 2012
Publication Date: July 31, 2012
Citation: Xu, L., Ji, Y., Zhou, H., Zhu, H., Thistle, H.W., Krause, C.R. 2012. Evaporation rate of emulsion and oil-base emulsion pheromones. ASABE Annual International Meeting. Paper no. 121340956.

Technical Abstract: Knowledge of pheromone evaporation rate is critical to distribute pheromone containers effectively in the forest, orchard and field. There are several factors influencing the pheromone evaporation rate that include wind speed, container size and porosity, release area, temperature, humidity, pheromone type, etc. In this research, the factors selected for the evaluation were three different types of liquid pheromones (Monochamus Alternatus Hope (MAH), Dendroctonus Valens LeConte (DVL), Flies sex attractant (FSA)), five release areas (50.2, 132.7, 254.0, 346.2, 660.2 mm2) and 11 wind speeds (0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 m/s). The MAH and DVL were emulsion while FSA was oil-based emulsion. Tests were conducted in a wind tunnel. When wind speeds were 0, 5, and 10 m/s, the MAH evaporation rates were 74.9, 678.1, and 1017.8 mg/h, and the DVL evaporation rates were 1.8, 218.2, and 480.1 mg/h, respectively. The evaporation rate of MAH and DVL increased as the increase of wind speed and release area. When wind speed increased from 0 to 5 m/s and then to 10 m/s, the evaporation rate of MAH with 50.2 mm2 release area increased from 6.4 to 8.8 mg/h and then substantially increased to 16.3 mg/h. With the same three wind speeds, the MAH evaporation rates were 74.9, 678.1, and 1017.9 mg/h when the release area was 660.2 mm2. However, the FSA evaporation rate was negative under all test conditions, which indicated that the FSA absorbed more amount of water from the ambient than the amount of pheromone released. Also, wind speed and release area had little effect on the FSA evaporation. These results demonstrated that the release area influenced the emulsion pheromone evaporation rate more than the wind speed. Therefore, the relationship between the extent of the porosity exposure and concentration of emulsion pheromone in containers should be determined to control its release and effectively cover target areas in forest and field applications. Evaporation of oil-based emulsion pheromone should be further investigated by avoiding the interference of moisture absorption.