Abstract The mechanism and critical elements of the honeydew from hemipterans responsible for enhanced invasiveness of invasive ants are highly diverse. This is due to the fact that the components of honeydew are complex and are modulated differentially across species and host plants. The present study therefore attempted to understand how the invasive yellow crazy ant (Anoplolepis gracilipes (Smith)) responds behaviorally to honeydew and how this response transforms into ecological success for this invasive pest ant. Eight carbohydrate components that are commonly present in hemipteran honeydew were offered to A. gracilipes, and preferences were observed. The performance of interspecific/ intraspecific competition and the colony growth between colonies treated with preferred carbohydrates and control also were compared. The results indicated that A. gracilipes significantly preferred melezitose and sucrose, with the consumption of the latter being tightly linked to increased colony productivity, but not for the former. The two preferred carbohydrates, however, showed no significant influence on the performance of interspecific/intraspecific competition for A. gracilipes. The patterns observed in the present study are consistent with previous findings for other invasive ants, suggesting that reducing the sources of carbohydrate (especially sucrose) may prevent outbreaks of the yellow crazy ant. Further applications based on this study are also discussed.
摘要 半翅目昆蟲產生之蜜露常被認為是加速入侵螞蟻族群擴張及增強其競爭力的主因之一，但蜜露成分極為複雜且因不同產蜜昆蟲物種與植物組合而異，若能確認蜜露中增強螞蟻入侵性(invasiveness) 之主要成分或其相關機制，將有助於後續防範措施之擬訂。本研究觀測百大入侵種之一的長腳捷山蟻 (Anoplolepis gracilipes (Smith)) 對於蜜露成分中各式醣類之偏好，並測試受偏好之醣類是否提升其入侵性。結果顯示，長腳捷山蟻最偏好蜜露中的松三糖 (melezitose) 與蔗糖 (sucrose)，且蔗糖有效增加幼體產量，但對於種內及種間競爭皆無顯著影響；松三糖則皆無影響。此結果符合前人假說，蔗糖為主要能量來源，能加速族群成長，而松三糖則僅具蜜露指示功能。後續防治策略除了控制環境中醣源 (尤其蔗糖) 避免長腳捷山蟻族群量增加外，或可考慮將松三糖應用於餌劑製作，將可提升餌劑誘引效率。
| Key words: hemipteran honeydew, invasive ants, melezitose, mutualism, sucrose | | 關鍵詞: 半翅目昆蟲蜜露、入侵螞蟻、松三糖、互利共生、蔗糖 |
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