Emilie Deletre, Mallent Maelle, Menut Chantal, Chandre Fabrice, Martin Thibaud
UR Hortsys, Cirad, Montpellier, France.
Institut des Biomolécules Max Mousseron, Faculté de Pharmacie, Montpellier, France.
J Econ Entomol. 2015 Aug;108(4):1890-901. doi: 10.1093/jee/tov118. Epub 2015 May 23.
In the Mediterranean region, the use of small-mesh netting to protect horticultural crops is an effective sustainable tool against pests. But in tropical regions, because of high humidity under the net favoring fungal development, netting with a larger mesh size has to be used, protecting crops against lepidopteran pests but not against small pests such as hemipterans, thrips, and phytophagous mites. A combination of netting with a repellent or irritant product is one possible solution, but the desire to reduce the use of synthetic chemicals and mitigate resistance issues calls for a natural alternative. The objective of this study was to evaluate the repellent, irritant, and toxic effects of nets dipped in 20 different plant extracts on Bemisia tabaci (Gennadius) adults. The repellent effect of volatile compounds was evaluated using a still-air olfactometer. The irritant effect and toxicity were evaluated with a no-choice test in tubes separated into two parts by an impregnated net. Our results showed the seven most irritant and toxic products against B. tabaci were aframomum, cinnamon, geranium, dill, citronella, litsea, and savory. The most repellent were aframomum and lemongrass, although cinnamon, geranium, and savory were also repellent at higher doses. Effects varied with the plant extract and the concentration, and effects were independent of one another, i.e., an essential oil can be irritant but not repellent, suggesting that the repellent mechanism and that behind the irritant or toxic effects is not the same. The use of repellent compounds in combination with netting as new pest control strategy is discussed.
在地中海地区，使用小网眼网来保护园艺作物是一种防治害虫的有效可持续工具。但在热带地区，由于网下高湿度有利于真菌生长，必须使用网眼尺寸更大的网，这种网能保护作物免受鳞翅目害虫侵害，但不能抵御半翅目、蓟马和植食性螨类等小型害虫。将网与驱避剂或刺激性产品结合使用是一种可能的解决方案，但减少合成化学品使用和缓解抗性问题的需求促使人们寻找天然替代品。本研究的目的是评估浸泡在20种不同植物提取物中的网对烟粉虱成虫的驱避、刺激和毒性作用。使用静态空气嗅觉仪评估挥发性化合物的驱避效果。通过在管中用浸渍网分隔成两部分的无选择试验评估刺激效果和毒性。我们的结果表明，对烟粉虱最具刺激性和毒性的七种产品是非洲豆蔻、肉桂、天竺葵、莳萝、香茅、山鸡椒和夏香薄荷。最具驱避性的是非洲豆蔻和柠檬草，不过肉桂、天竺葵和夏香薄荷在高剂量时也具有驱避性。效果因植物提取物和浓度而异，且各效果相互独立，即一种精油可能具有刺激性但不具有驱避性，这表明驱避机制与刺激或毒性作用背后的机制不同。本文讨论了将驱避化合物与网结合作为新的害虫防治策略的应用。
