Journal of Economic Entomology (1995) 88, 649-653

Rudolf H. Scheffrahn, Gregory S. Wheeler and Nan-Yao Su (1995)
Synergism of methyl bromide and sulfuryl fluoride toxicity against termites (Isoptera: Kalotermitidae, Rhinotermitidae) by admixture with carbon dioxide
Journal of Economic Entomology 88 (3), 649-653
Abstract: Toxicities of methyl bromide and sulfuryl fluoride in combination with CO₂ were assessed against pseudergates of Incisitermes snyderi (Light) and workers of Coptotermes formosanus Shiraki. Estimates of lethal accumulated doses (LAD, 20-h exposure) of methyl bromide for 99% mortality against I. snyderi were 50, 37, 28, and 28 mg x h/liter and, for sulfuryl fluoride, 45, 30, 30, and 33 mg x h/liter at 0, 5, 10, and 20% CO₂ (vol:vol), respectively. LAD₉₉ values against C. formosanus with methyl bromide were 38, 32, 24, and 24 mg x h/liter and, for sulfuryl fluoride, 45, 29, 20, and 28 mg x h/liter at 0, 5, 10, and 20% CO₂ (vol:vol), respectively. In general, CO₂ enhanced the toxicity of methyl bromide against I. snyderi more than against C. formosanus, whereas CO₂ increased the toxicity of sulfuryl, fluoride against C. formosanus more than against I. snyderi. Based on LAD₉₉ values against I. snyderi, a maximum synergism ratio (SR) of 1.8 was induced by CO₂ in admixture with methyl bromide at 10 or 20% CO₂. For C. formosanus, a maximum SR of 2.2 was attained with 10% CO₂ when combined with sulfuryl fluoride. These results indicate that the application rates of structural fumigants may be reduced by the simultaneous addition of 10% CO₂ into fumigated airspace.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Database assignments for author(s): Nan-Yao Su

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.
	Coptotermes formosanus		U.S.A. (SE)
	Incisitermes snyderi		U.S.A. (SE)