Ovicidal effect of the essential oils from 18 Brazilian Piper species: controlling Anticarsia gemmatalis (Lepidoptera, Erebidae) at the initial stage of development

ABSTRACT. The toxicities of essential oils (EOs) from 18 species of Brazilian Piperaceae were assessed on eggs of the velvetbean caterpillar, Anticarsia gemmatalis. Oils were extracted using steam distillation, and dilutions were made for bioassays at concentrations of 0.25, 0.5, 1.0, 2.0, and 4.0%. All EOs reduced larval hatching. The lowest lethal concentrations were obtained from Piper fuligineum (SP), Piper mollicomum “chemotype 1” (SP), Piper mosenii (PR), Piper aduncum (PA) and Piper marginatum (PA). Ovicidal activity is related to the potential toxicity of several compounds, especially dilapiolle, myristicin, asaricine, spathulenol and piperitone. According to our results, EOs from 16 Brazilian Piper species have potential for use as biorational botanical insecticides.

摘要：本研究评估了18种巴西胡椒科（Piperaceae）植物精油（essential oils, EOs）对绒豆夜蛾（Anticarsia gemmatalis）卵的毒性。采用水蒸气蒸馏法（steam distillation）提取精油，并配制浓度为0.25%、0.5%、1.0%、2.0%及4.0%的稀释液进行生物测定（bioassays）。所有受试精油均可降低幼虫孵化率，其中褐胡椒（Piper fuligineum, SP）、软毛胡椒"化学型1"（Piper mollicomum "chemotype 1", SP）、莫森胡椒（Piper mosenii, PR）、弯柄胡椒（Piper aduncum, PA）及缘叶胡椒（Piper marginatum, PA）的最低致死浓度最低。该类精油的杀卵活性（ovicidal activity）与多种化合物的潜在毒性密切相关，尤以莳萝脑（dilapiolle）、肉豆蔻醚（myristicin）、细辛素（asaricine）、斯巴醇（spathulenol）及胡椒酮（piperitone）最为显著。本研究结果表明，16种巴西胡椒属植物精油具备开发为生物合理型植物源杀虫剂（biorational botanical insecticides）的应用潜力。