Field Trials on Biogenerated V-HF System to Control the Large Narcissus Fly
Simcha Finkelman1*, Shlomo Navarro1, Miriam Rindner1, Refael Dias1 and Tamir Hezy2
1Department of Food Science, Agricultural Research Organization, The Volcani Center, P.O Box 6, Bet Dagan 50 -250, Israel
2Ethan Amichai Nationwide Exterminating (Israel) Ltd., P.O Box 2272, Ramat-Gan, Israel
E mail: <simchaf@volcani.agri.gov.il>
Abstract: The recent introduction of flexible transportabl e sealed chambers made of welded PVC liners has opened new opportunities to implement low pressures (Vacuum treatment) as a competitive and affordable treatment to control storage insect pests. Under vacuum, these chambers shrink over the periphery of the commodity and hold it fast. The system is sealed by an air-tight zipper and is able to retain vacuum. At the base of the chamber an inlet hose enables connection to the vacuum pump that creates the prerequisite low pressure.
Our studies showed that it is not a practical approach to attempt to hold a pressure of below 45 mm Hg because of the energy required for prolonged operation of the pump. Conversely, pressures above 55 mm Hg prolong the time to achieve kill. In contrast to fumigations where schedules are provided by defining dosages to be applied for a predetermined time, at a set temperature range, low pressure treatment schedules must be presented as exposure times at both, a temperature range and a relative humidity that is in equilibrium with the commodity moisture content.
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