Abstract This paper reports on the effect of calcium carbonate particles in the protection of plants against the two-spotted mite (Tetranychus urticae Koch). The calcium carbonate particles scratch the exoskeletons of these pests, block their spiracles, reduce activity, and may also result in severe dehydration. The two-spotted mite is a significant economic pest and exhibits substantial resistance to pesticides due to the frequent applications of chemical synthesized pesticides. Thus, non-chemical synthesized pesticides are increasingly being recommended for use in the field. In this study, we tested the susceptibility of two-spotted mites to two different grain sizes of calcium carbonate particles, a 19.5% calcium carbonate suspension concentrate (≈ 100 nm) and a 95% bulk calcium carbonate powder (> 1 μm). Neither of these 2 grain sizes showed a dose response relationship to infestations by the two-spotted mite. The mortality rates were only 14% and 16% at the highest concentration for calcium carbonate suspension concentrate and bulk calcium carbonate powder, respectively. We hope to find more suitable and more effective materials and better application methods for controlling two-spotted mites in the future.
摘要 礦物質微粒因顆粒細小，施用時可使昆蟲外骨骼受到其粒子刮傷或堵塞氣孔，進而影響活動力及改變行為、使蟲體脫水或造成死亡的防治效果。二點葉蟎 (Tetranychus urticae Koch) 為經濟作物重要的害蟲，因大量施用合成性農藥來進行防治，已對傳統化學農藥產生抗藥性，故本研究應用非農藥資材如碳酸鈣微粒來進行其相關防治效果之探討，以19.5% 碳酸鈣微粒 (約100奈米等級) 以及95% 一般碳酸鈣粉劑 (微米等級) 二種成品，稀釋後對二點葉蟎進行感受性測定。結果顯示二點葉蟎施用兩種碳酸鈣後死亡率都不呈劑量反應，且碳酸鈣微粒和一般碳酸鈣粉劑最高施用濃度下的死亡率僅分別為14% 和16%。本試驗結果顯示碳酸鈣微粒對二點葉蟎沒有防治效果。未來將針對二點葉蟎尋找並開發較理想之防治資材及施用方法，以有效對其進行防治。
| Key words: Tetranychus urticae, susceptibility, calcium carbonate nanoparticles | | 關鍵詞: 二點葉蟎、感受性、碳酸鈣微粒。 |
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