International Centre of Insect Physiology and Ecology, P. O. Box 30772-00100, Nairobi, Kenya.
Department of Agricultural Sciences, South Eastern Kenya University, P.O Box 170-90200, Kitui, Kenya.
J Chem Ecol. 2024 Nov;50(11):778-789. doi: 10.1007/s10886-024-01485-y. Epub 2024 Mar 12.
The cabbage aphid (Brevicoryne brassicae) is a major pest of kale (Brassica oleraceae var. acephala), an important vegetable that is grown worldwide due to its high nutritional and economic value. Brevicoryne brassicae poses a great challenge to B. oleraceae var. acephala production, causing significant direct and indirect yield losses. Farmers overly rely on synthetic insecticides to manage the pest with limited success owing to its high reproductive behavior and development of resistance. This necessitates a search for sustainable alternatives to mitigate these challenges. This study assessed behavioral responses of B. brassicae to odors from rosemary (Rosmarinus officinalis) and B. oleraceae var. acephala headspace volatiles in a Perspex four-arm olfactometer. We identified and quantified volatiles emitted by each of the two plants and those eliciting antennal response using coupled gas chromatography-mass spectrometry (GC-MS) and GC-electroantennograhic detection(GC-EAD), respectively. Our findings revealed that B. brassicae spent more time in the arms of the olfactometer that contained B. oleraceae var. acephala volatiles compared to the arm that held R. officinalis volatiles. Additionally, B. brassicae spent more time in the olfactometer arms with B. oleracea var. acephala compared to the arms holding B. oleracea var. acephala and R. officinalis enclosed together and clean air. GC-MS analysis revealed diverse and higher quantities of volatile compounds in R. officinalis compared to B. oleraceae var. acephala. GC-EAD analysis showed that antennae of B. brassicae detected Linalool, α-Terpineol, Verbenone, Geraniol, Camphor, and Borneol from the volatiles of R. officinalis, and Sabinene, γ-Terpinene, and β-Caryophyllene from B. oleraceae var. acephala volatiles. Our findings demonstrate the potential of R. officinalis as a repellent plant against B. brassicae and could be utilized as a 'push' plant in an intercropping strategy against this pest.
甘蓝蚜（Brevicoryne brassicae）是一种重要蔬菜——皱叶甘蓝（Brassica oleraceae var. acephala）的主要害虫。由于其高营养价值和经济价值，皱叶甘蓝在全球范围内广泛种植。甘蓝蚜的存在对皱叶甘蓝的生产构成了巨大挑战，导致了显著的直接和间接产量损失。由于其高繁殖行为和抗药性的发展，农民过度依赖合成杀虫剂来管理这种害虫，但效果有限。这就需要寻找可持续的替代方法来缓解这些挑战。
本研究使用 Perspex 四臂嗅觉仪评估了甘蓝蚜对迷迭香（Rosmarinus officinalis）和皱叶甘蓝头部分泌物挥发物气味的行为反应。我们使用气相色谱-质谱联用仪（GC-MS）和 GC-触角电位检测（GC-EAD）分别鉴定和量化了这两种植物释放的挥发物，以及那些能引起触角反应的挥发物。我们的研究结果表明，与含有迷迭香挥发物的嗅探臂相比，甘蓝蚜在含有皱叶甘蓝挥发物的嗅探臂中停留的时间更长。此外，与含有皱叶甘蓝和迷迭香混合物以及清洁空气的嗅探臂相比，甘蓝蚜在含有皱叶甘蓝挥发物的嗅探臂中停留的时间更长。GC-MS 分析表明，迷迭香中含有更多种类和更高数量的挥发性化合物。GC-EAD 分析表明，甘蓝蚜的触角检测到了来自迷迭香挥发物的罗勒烯、α-松油醇、马鞭草酮、牻牛儿醇、樟脑和龙脑，以及来自皱叶甘蓝挥发物的柠檬烯、γ-松油烯和β-石竹烯。
我们的研究结果表明，迷迭香可能是一种驱避甘蓝蚜的植物，可作为一种“推”植物，用于对抗这种害虫的间作策略。
