Synergistic Effect of Additional Gas on the Toxicity of Phosphine to Sitophilus oryzae and Sitophilus zeamais (Coleoptera: Dryophthoridae)

Sitophilus spp. is the most serious pest in imported brown rice warehouses, and its phosphine resistance has been observed in Taiwan. To overcome the efficiency decline of phosphine fumigation to Sitophilus beetles, phosphine fumigation with additional gas is the most noticed practice internationally. In this study, we evaluated the toxicity increase of phosphine in the presence of additional 10–20% of CO2, O2, or N2 to Sitophilus beetles for 20 h or 72 h of fumigation. We found that there was no synergism between phosphine and additional gas for phosphine-resistant Sitophilus oryzae (Linnaeus) strains with 20 h fumigation. However, when the fumigation period prolonged to 72 h, the LC50 of phosphine with additional 10 or 20% of CO2, or N2 decreased from 13.8 to 2.9–11.0 μg L-1 for Houbi strain of S. oryzae. We consider that additional CO2, and N2 can potentially enhance the toxicity of phosphine against phosphine-resistant stored-product pests in the imported rice warehouse. 米象屬昆蟲 (Sitophilus spp.) 為臺灣進口米倉庫中最嚴重的積穀害蟲，在臺灣已發現對磷化氫產生抗藥性，為克服磷化氫燻蒸對米象屬害蟲防治效果的下降，額外添加氣體與磷化氫共同燻蒸為當前國際最關注的方法。在本研究中，我們評估額外添加10–20% 二氧化碳、氧氣或氮氣與磷化氫共同燻蒸對米象屬甲蟲之致死效果的提升，我們發現燻蒸20 h，磷化氫與三種氣體對於抗藥性米象不會產生任何協力作用，然而將燻蒸時間延長至72 h，添加10–20% 二氧化碳與氮氣即有助於提升磷化氫對於後壁品系米象之致死效果，其LC50從13.8 μg L-1 降至 2.9–11.0 μg L-1，因此我們認為在磷化氫燻蒸時添加二氧化碳或氮氣，具有提升磷化氫對於進口米倉庫內磷化氫抗藥性積穀害蟲的致死效果。

Subjects

sitophilus

phosphine

CO2

O2

N2

米象類

磷化氫

二氧化碳

氧氣

氮氣

Publisher

農業試驗所

Type

journal article

File(s)

Name

73-1-1.pdf

Size

876.15 KB

Format

Adobe PDF

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