07/09/2026
【居家防蟲植物】
👉1. 檸檬香茅（Cymbopogon citratus／C. nardus）
🌿主成分： 檸檬醛（neral＋geranial）、香茅醛、香茅醇、香葉醇。
🌿對象： 埃及伊蚊、白線斑蚊、致倦庫蚊、岡比亞按蚊、中華按蚊幼蟲；蟑螂、螞蟻亦有接觸／忌避資料。
👉2. 薄荷（Mentha spp.，尤以胡椒薄荷 M. piperita、綠薄荷 M. spicata）
🌿主成分： 薄荷腦（menthol）、薄荷酮、檸檬烯。
🌿對象： 蚊成蟲與幼蟲、螞蟻、蚜蟲、儲糧甲蟲、蟑螂（接觸時）。
👉3. 薰衣草（Lavandula angustifolia 等）
🌿主成分： 芳樟醇、乙酸芳樟酯、1,8-桉油醇。
🌿對象： 庫蚊、埃及伊蚊幼蟲／成蟲；部分農業薊馬、蚜蟲、馬鈴薯甲蟲文獻亦有拒食／觸殺。
👉4. 香葉天竺葵（Pelargonium graveolens；市售「防蚊天竺葵／citrosa」常為 P. citrosum）
🌿主成分： β-香茅醇、香葉醇（geraniol）。香葉醇是少數被歐盟生物殺劑指令承認的天然驅避活性物質之一。
🌿對象： 按蚊、伊蚊；民間亦稱可驅蜱、白粉蝨、日本金龜子，但後者證據較雜。
👉5. 艾草／艾蒿（Artemisia argyi 為華語區主流；亦含其他蒿屬）
🌿主成分： 因產地差異大——桉油醇、樟腦、側柏酮、植醇；2024 年武漢大學團隊在《JACS》以基因導向方法鑑定出新驅蟲萜類艾蒿醇（mugwort alcohol）。
🌿對象： 中華按蚊、埃及伊蚊、蜱、部分農業害蟲；傳統「端午掛艾、燒艾煙」。
👉6. 鼠尾草（Salvia officinalis 為研究主力）
🌿主成分： α-側柏酮、樟腦、1,8-桉油醇。
🌿對象： 儲糧害蟲為主（穀象、豆象、擬穀盜），衛生害蟲資料少於香茅／薄荷。
👉7. 迷迭香（Salvia rosmarinus，舊名 Rosmarinus officinalis）
🌿主成分： 1,8-桉油醇、樟腦、α-蒎烯、馬鞭草烯酮。
🌿對象： 儲糧甲蟲、二斑葉蟎、薊馬、粉蝨、庫蚊／伊蚊（幼蟲活性常優於成蟲忌避）。
👉8. 芳香萬壽菊（Tagetes erecta／T. patula／T. minuta）
🌿主成分：地上部精油：羅勒烯、檸檬烯、tagetone 等 → 殺蟲、殺蚊幼蟲。
🌿根部分泌 α-三噻吩（α-terthienyl） → 線蟲毒、光活化殺幼蟲，是這類植物最獨特、也最被農業試驗站採用的機制。
👉9. 左手香（Plectranthus amboinicus＝Coleus amboinicus，到手香）
🌿主成分： 香芹酚（carvacrol，常見 70% 上下）、百里香酚、對聚繖花素。
🌿對象： 埃及伊蚊、儲糧甲蟲（穀盜、玉米象、豆象）、螞蟻（萃取物）。
👉10. 豬籠草（Nepenthes spp.）
這一種和其他九種不是同一類防蟲策略。
🌿機制是捕蟲器綜合徵：蜜腺引誘 ＋ 唇緣濕滑 ＋ 蠟質內壁讓蟲腳打滑 ＋ 消化液表面活性讓蟲溺斃。仿生管試驗顯示，液體潤濕性（含界面活性劑）對捕捉效率影響最大，籠口直徑次之。
🌿葉片另含萘醌類（如 plumbagin）作為抗植食性昆蟲的預存防禦，斜紋夜蛾取食幾乎不增重。
🌿它吸引並吃掉靠近的蟲，不會在庭院形成「驅蟲氣場」，也不能取代紗窗或驅避劑。作為觀葉／科普／少量捕捉果蠅尚可，當衛生害蟲防治不切實際。
👉植物防蟲大致有四條路：
🍀氣味忌避（repellent）：單萜／酚類（檸檬醛、香茅醛、香葉醇、香芹酚、薄荷腦、芳樟醇、樟腦、1,8-桉油醇）干擾昆蟲嗅覺定位 CO₂、乳酸、體味。
🍀熏蒸／觸殺（fumigant / contact）：高濃度下可麻痺或致死，常見於儲糧害蟲、蟑螂、幼蟲。
🍀化感／土壤活性（allelopathy）：萬壽菊根部分泌 α-三噻吩，主要對線蟲。
🍀物理捕捉：豬籠草是食蟲植物，用籠蓋、蠟質內壁與消化液捕捉昆蟲，不是靠香氣把蟲趕走。
👉防蟲實證：
🍀美國環保署已登記的植物源驅蚊單體包括檸檬醛、香茅醇、薄荷醇、芳樟醇、香葉醇等，正好對應香茅、薄荷、薰衣草、天竺葵這類精油的主成分。
🍀實務上幾乎所有研究都指出： 濃度愈高、劑型愈能緩釋（膏、乳膠、奈米脂質體、布料貼片），持效愈接近 DEET；單純種植或點香茅蠟燭，田間結果常不穩定，有的試驗甚至與「普通蠟燭煙霧」無顯著差異。
🍀若目標是病媒蚊皮膚防護： 優先考慮香茅／香茅醛衍生物、左手香 10% 緩釋貼片或布料、天竺葵精油緩釋膠；仍建議在高風險區與 DEET／派卡瑞丁互備，因為多數植物油完整保護多在 1–4 小時。
🍀若目標是家中螞蟻、蟑螂： 薄荷、香茅酒精噴霧對路徑與接觸有效，但不能清巢；香草常常被蟲忽略。
🍀若目標是菜園： 迷迭香間作有田間蟲情下降資料；萬壽菊輪作／密植是線蟲管理的經典做法，不是防蚊花壇。
🍀若目標是米桶、香料櫃： 鼠尾草、迷迭香、左手香精油熏蒸方式文獻最多。
🍀豬籠草為食蟲植物，非「驅蟲香草」
#驅蟲香草 #植萃香氛 #共耕農藝小學堂 #轉載與教學用途請註明來源出處
[Pest-Repelling Plants for the Home]
👉1. Lemon Lemongrass (Cymbopogon citratus / C. nardus)
🌿Main Components: Citral (neral + geranial), citronellal, citronellol, geraniol.
🌿Targets: Larvae of Aedes aegypti (Yellow fever mosquito), Aedes albopictus (Asian tiger mosquito), Culex quinquefasciatus (Southern house mosquito), Anopheles gambiae, and Anopheles sinensis; data also exists regarding contact/repellency against cockroaches and ants.
👉2. Mint (Mentha spp., especially Peppermint M. piperita, Spearmint M. spicata)
🌿Main Components: Menthol, menthone, limonene.
🌿Targets: Adult and larval mosquitoes, ants, aphids, stored-grain beetles, cockroaches (upon contact).
👉3. Lavender (Lavandula angustifolia etc.)
🌿Main Components: Linalool, linalyl acetate, 1,8-cineole.
🌿Targets: Culex mosquitoes, Aedes aegypti larvae/adults; literature also reports antifeedant/contact-killing effects on certain agricultural thrips, aphids, and Colorado potato beetles.
👉4. Rose Geranium (Pelargonium graveolens; commercially sold "Citrosa/Mosquito Geranium" is often P. citrosum)
🌿Main Components: β-citronellol, geraniol. Geraniol is one of the few natural repellent active substances recognized by the EU Biocidal Products Directive.
🌿Targets: Anopheles, Aedes; colloquially claimed to repel ticks, whiteflies, and Japanese beetles, though evidence for the latter is mixed.
👉5. Mugwort / Chinese Wormwood (Artemisia argyi is predominant in Chinese-speaking regions; also includes other Artemisia spp.)
🌿Main Components: Varies greatly by origin—cineole, camphor, thujone, phytol; in 2024, a Wuhan University team identified a new repellent terpene, "mugwort alcohol," in 《JACS》 using a gene-guided approach.
🌿Targets: Anopheles sinensis, Aedes aegypti, ticks, some agricultural pests; traditional practice of "hanging mugwort during the Dragon Boat Festival, burning mugwort smoke."
👉6. Sage (Salvia officinalis is the main focus of research)
🌿Main Components: α-thujone, camphor, 1,8-cineole.
🌿Targets: Primarily stored-grain pests (rice weevil, bean weevil, flour beetle); less data exists for hygiene pests compared to lemongrass/mint.
👉7. Rosemary (Salvia rosmarinus, formerly Rosmarinus officinalis)
🌿Main Components: 1,8-cineole, camphor, α-pinene, verbenone.
🌿Targets: Stored-grain beetles, two-spotted spider mites, thrips, whiteflies, Culex/Aedes (larvicidal activity is often superior to adult repellency).
👉8. Scented Marigold (Tagetes erecta / T. patula / T. minuta)
🌿Main Components:
Aerial part essential oil: Ocimene, limonene, tagetone, etc. → Insecticidal, larvicidal against mosquitoes.
Roots secrete α-terthienyl → Nematicidal, photo-activated larvicide; this is the most unique mechanism of this plant class and the one most adopted by agricultural experimental stations.
👉9. Mexican Mint / Cuban Oregano (Plectranthus amboinicus = Coleus amboinicus)
🌿Main Components: Carvacrol (commonly around 70%), thymol, p-cymene.
🌿Targets: Aedes aegypti, stored-grain beetles (flour beetle, maize weevil, bean weevil), ants (extract).
👉10. Pitcher Plant (Nepenthes spp.)
This species utilizes a different pest control strategy compared to the other nine.
🌿The mechanism is the "pitfall trap syndrome": Nectar gland attraction + slippery peristome (rim) + waxy inner wall causing insect feet to slip + digestive fluid surface activity causing insect drowning. Biomimetic tube experiments show that liquid wettability (including surfactants) has the greatest impact on capture efficiency, followed by pitcher mouth diameter.
🌿The leaves also contain naphthoquinones (such as plumbagin) as a pre-existing defense against herbivorous insects; Spodoptera litura (to***co cutworm) feeding on them gains almost no weight.
🌿It attracts and eats nearby insects; it does not form a "repellent field" in the yard, nor can it replace window screens or repellents. It is acceptable as an ornamental plant, for scientific education, or for catching small amounts of fruit flies, but using it for hygiene pest control is impractical.
👉There are roughly four paths for plant-based pest control:
🍀Repellent (Odor Repellency): Monoterpenes/phenols (citral, citronellal, geraniol, carvacrol, menthol, linalool, camphor, 1,8-cineole) interfere with insect olfactory positioning of CO₂, lactic acid, and body odor.
🍀Fumigant / Contact Killing: Paralysis or death at high concentrations, common with stored-grain pests, cockroaches, and larvae.
🍀Allelopathy / Soil Activity: Marigold roots secrete α-terthienyl, primarily targeting nematodes.
🍀Physical Capture: Pitcher plants are carnivorous plants that capture insects using lids, waxy inner walls, and digestive fluids, rather than driving them away with aroma.
👉Pest Control Evidence:
🍀Plant-derived mosquito repellent monomers registered with the US EPA include citral, citronellol, menthol, linalool, geraniol, etc., which correspond exactly to the main components of essential oils like lemongrass, mint, lavender, and geranium.
🍀In practice, almost all studies indicate: The higher the concentration and the better the slow-release formulation (balms, latex, nanoliposomes, fabric patches), the closer the efficacy duration is to DEET. Simply planting them or lighting citronella candles often yields unstable field results; some experiments even show no significant difference from "ordinary candle smoke."
🍀If the goal is skin protection against disease vectors: Prioritize citronella/citronellal derivatives, Mexican Mint 10% slow-release patches or fabrics, or geranium essential oil slow-release gels. It is still recommended to back these up with DEET/Picaridin in high-risk areas, as complete protection from most plant oils lasts only 1–4 hours.
🍀If the goal is ants or cockroaches in the home: Mint or citronella alcohol sprays are effective on trails and contact, but cannot eliminate the nest; live herb plants are often ignored by insects.
🍀If the goal is the vegetable garden: Data exists for reduced field pest occurrence with rosemary intercropping; marigold rotation/dense planting is a classic practice for nematode management, not an anti-mosquito flowerbed.
🍀If the goal is rice bins or spice cabinets: Sage, rosemary, and Mexican Mint essential oil fumigation methods have the most supporting literature.
🍀Note: Pitcher plants are carnivorous plants, not "pest-repelling herbs."
