Liu-pao Tea as a Source of Botanical Oviposition Attractants for Aedes Mosquitoes

Simple SummaryDiseases transmitted byAedesmosquitoes, including dengue, Zika, and chikungunya, lack effective vaccines and specific treatments, making vector control critical for disease prevention. Oviposition attractants offer a promising tool for managing mosquito populations. Effective oviposition attractants forAedesmosquitoes are urgently needed. While green tea attractsAedes aegypti, it is unclear how different tea fermentations affect the Asian tiger mosquito (Aedes albopictus). We tested teas across fermentation stages, evaluating attraction, the role of microbes, and chemicals. Results showed aged Liu-pao tea strongly attracts them at 5 g/L after 1–2 weeks. Notably, even a weak Liu-pao (0.5 g/L) solution successfully attractedAe. aegyptimosquitoes with an oviposition activity index (OAI) of 0.89 (day 21). Crucially, we discovered that this attraction was not due to living microbes in the tea water, but rather natural chemicals released from the tea leaves. Also, we identified one specific chemical, cedrol, as part of this attraction, but found that the full tea solution worked much better than cedrol alone. These findings establish Liu-pao tea as a potent botanical attractant and support the development of multi-volatile “attract-and-kill” strategies for gravidAedesmosquitoes.Oviposition attractants can enhance both the surveillance and control of container-breedingAedesmosquitoes. Although green tea has been reported to attractAe. aegypti, the specific bioactive botanical compounds responsible remain unidentified. We evaluated teas across fermentation stages (non-fermented, fully fermented, and post-fermented) at 5 g/L for gravidAe. albopictususing dual-choice assays. The most attractive tea (Liu-pao) was further tested across concentrations (0.5–5 g/L) and infusion ages (1–28 days). Autoclaved vs. non-autoclaved infusions assessed microbial contributions, while headspace volatiles were analyzed via HS-SPME-GC-MS. Individual compounds (cedrol and linalool oxide) were bioassayed. Only Liu-pao tea consistently attractedAe. albopictus(OAI ≥ 0.3), peaking at 5 g/L after 7–14 days (OAIs 0.73/0.67). A 0.5 g/L infusion aged 21–28 days also attractedAe. aegypti(OAIs 0.89/0.63). Autoclaving did not reduce attraction, confirming volatile compounds, not live microbe-mediated effects. Cedrol (1 mg/L) elicited moderate attraction (OAI 0.29) inAe. albopictus, while linalool oxide was inactive. Post-fermented Liu-pao tea acts as a potent botanical attractant forAedesmosquitoes. Cedrol contributes partially, but whole tea infusions outperform single compounds. These findings support developing multi-volatile “attract-and-kill” strategies targeting gravid mosquitoes.