Journal of Economic Entomology (2008) 101, 623-630

Yonglin Ren, Byungho Lee, Daphne Mahon, Ni Xin, Matthew Head and Robin Reid (2008)
Fumigation of wheat using liquid ethyl formate plus methyl isothiocyanate in 50-tonne farm bins
Journal of Economic Entomology 101 (2), 623-630
Abstract: Australian Standard White wheat, Triticum aestivum L. (a marketing grade with mixed grain hardness), with a moisture content of 12.5% was fumigated with a new ethyl formate formulation (95% ethyl formate plus 5% methyl isothiocyanate) identified and developed by Commonwealth Scientific and Industrial Research Organization Entomology, Canberra, Australia. Wheat was fumigated with the formulation at a calculated application rate of 80 g/m³ in two 50-tonne sealed metal vertical silos located at Fisherman Islands, Queensland, Australia. Access was gained through the top of the silo where the application of the formulation was completed within a few minutes by pouring it onto the top of the wheat. After 2 h of recirculation, using a 0.5-kW fan, the in-bin concentrations of ethyl formate achieved equilibrium with a concentration variation <7%. The ethyl formate concentration, in both silos 1 and 2, during the first day's exposure period remained above 10 g/m³. The concentration of ethyl formate by time product achieved was 790 and 650 g h/m³ in silos 1 and 2, respectively. In silo 1, the formulation was sufficient to kill all life stages of mixed age cultures of Sitophilus oryzae (L.), Rhyzopertha dominica (F.), and Tribolium castaneum (Herbst). In silo 2, control was 100% for R. dominica and T. castaneum and 99.4% for S. oryzae. After 5 d fumigation, the silo top-hatch was opened but no forced aeration was initiated. The in-bin concentration of ethyl formate was lower than the Australian experimental threshold limit value of 100 ppm. The ethyl formate and methyl isothiocyanate residues in the grain had declined to below the Australian experimental maximum residue limit of 0.2 and 0.1 mg/kg, respectively. The workspace and environmental levels of ethyl formate and methyl isothiocyanate were less than the detection limit of 0.1 ppm. The treatment with ethyl formate formulation had no affect on the wheat germination and seed color compared with untreated controls.
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Link to article at publishers website
Database assignments for author(s): YongLin Ren, Byung-Ho Lee

Research topic(s) for pests/diseases/weeds:
control - general

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Tribolium castaneum	Stored grain	Australia (NT+QLD)
	Sitophilus oryzae	Stored grain	Australia (NT+QLD)
	Rhyzopertha dominica	Stored grain	Australia (NT+QLD)