The aim of this study was to evaluate the repellent activity and contact toxicity of ethanolic extracts from non-host plant species against the brown planthopper (BPH), Nilaparvata lugens. We prepared ethanolic extracts from 11 plant species widely distributed in southern China, and tested their effects on BPH stage 3~4 nymphs using a film bioassay. The results showed that the extracts from Zanthoxylum bungeanum and Foeniculum vulgare had anti-feeding activity against BPH nymphs at a concentration of 10 mg·mL-1. These Z. bungeanum and F. vulgare extracts also had repellent activity, with repellent rates of 53.3% and 43.3%, respectively, at 24 h after extract application. In contrast, the extracts from Khaya senegalensis, Ageratum conyzoides, Eucalyptus exserta, and Chukrasia tabularis showed attractant activity at a concentration of 10 mg·mL-1;we recorded landing rates of 75.0%, 73.3%, 73.3%and 71.7%, respectively, at 24 h after extract application. Furthermore, the repellent activity of Z. bungeanum and F. vulgare extracts increased as the concentration increased. For example, these extracts at a concentration of 40 mg·mL-1 showed 66.7% and 60.0% repellent rates, respectively, at 24 h after extract application. The extracts from Z. bungeanum and F. vulgare showed significant repellent activity in the concentration range of 10~40 mg·mL-1. The attractant activity of extracts from K. senegalensis, A. conyzoides, E. exserta, and C. tabularis increased at relatively low concentrations, but decreased as the concentration of the extract became higher. The effects of ethanolic extracts from K. senegalensis and C. tabularis on BPH nymphs were different at different concentrations;at a low concentration (10 mg·mL-1), they showed significant attractant activity to BPH nymphs, while at a high concentration (40 mg·mL-1), they showed repellant activities of 50.0%and 40.0%, respectively, at 24 h after extract application. The extract from A. conyzoides had a significant attractant activity at 5 and 10 mg·mL-1, with landing rates of 71.7%and 73.3%, respectively, at 24 h after extract application. The extract from E. exserta had a significant attractant activity at 10 and 20 mg·mL-1, with landing rates of 73.3%and 71.7%, respectively, at 24 h after extract application. The extracts from Capsicum annuum, F. vulgare, Z. bungeanum, A. conyzoides and Bidens pilosa showed significant contact toxicity, the corrected mortality rates were higher than 85%at 95.69μg·cm-2 after 24 h;the LD50 of these five plant extracts to BPH nymphs were 15.46, 25.66, 33.61, 33.57 and 37.85 μg·cm-2, respectively. The extracts from K. senegalensis and Wedelia chinensis also showed contact toxicity, the corrected mortality rates were higher than 50%at 95.69μg·cm-2 after 24 h. The 11 non-host plant species were in different families and genera, and showed different repellent activities to BPH nymphs depending on the concentration of the ethanolic extract. The extracts from C. annuum, F. vulgare, Z. bungeanum, A. conyzoides, and B. pilosa showed significant contact toxicity. C. annuum, F. vulgare, and Z. bungeanum are crop species. The results of this study suggest that these three crops have the potential for the development of bio-pesticides. A. conyzoides and B. pilosa are abundant, easy to collect, and widely distributed in southern China. Therefore, these two species also have the potential for development as botanical insecticides.%为了评估非寄主植物次生物质对褐飞虱3~4龄若虫的驱避与触杀活性，本文用乙醇浸提了11种在华南地区分布广泛的植物获得其乙醇提取物。分析了这11种植物乙醇提取物对褐飞虱3~4龄若虫的驱避作用，采用药膜法测定了其对褐飞虱3~4龄若虫的触杀作用。结果表明，10 mg·mL-1的质量浓度下，花椒（Zanthoxylum bungeanum）和小茴香（Foeniculum vulgare）提取物对褐飞虱若虫有显著地拒避作用，24 h的拒避率分别为53.3%和43.3%；塞楝(Khaya senegalensis)、胜红蓟(Ageratum conyzoides)、桉树(Eucalyptus exsetrta)和毛麻楝（Chukrasia tabularis）提取物对褐飞虱若虫有显著地引诱作用，24 h着落率分别为75.0%、73.3%、73.3%和71.7%。花椒和小茴香提取物对褐飞虱若虫的拒避作用随着质量浓度的上升而增加，在10~40 mg·mL-1的质量浓度下均对褐飞虱3~4龄若虫有显著地拒避活性，40 mg·mL-1时拒避作用最明显，24 h拒避率分别为66.7%和60.0%。塞楝、胜红蓟、桉树和毛麻楝提取物对褐飞虱若虫的引诱作用均随着质量浓度的上升先增加后降低。塞楝和毛麻楝乙醇提取物对褐飞虱若虫的拒避与引诱活性因其质量浓度的不同而有差异，当质量浓度小时（10 mg·mL1）对褐飞虱若虫有显著地引诱作用；当质量浓度大时（40 mg·mL1）对褐飞虱若虫有显著地拒避作用，24 h后，拒避率分别为50.0%和40.0%。胜红蓟乙醇提取物在5和10 mg·mL-1的质量浓度下对褐飞虱若虫具有显著地引诱作用，24 h后，着落率分别为71.7%和73.3%；桉树乙醇提取物在10和20 mg·mL-1的质量浓度下对褐飞虱若虫具有显著地引诱作用，24 h后，着落率分别为73.3%和71.7%。辣椒（Capsicum annuum）、小茴香、花椒、胜红蓟和鬼针草（Bidens pilosa）乙醇提取物对褐飞虱若虫的触杀活性效果显著，在95.69μg·cm-2的剂量下，24 h校正死亡率达到85%以上，LD50值依次为15.46，25.66，33.61，33.57和37.85μg·cm-2。塞楝和蟛蜞菊（Wedelia chinensis）提取物对褐飞虱若虫也具有较好地触杀活性，在95.69μg·cm-2的剂量下，24 h校正死亡率达到50%以上。研究所选11种不同科属非寄主植物的乙醇提取物在一定质量浓度下，对褐飞虱均会产生不同程度的拒避作用。其中辣椒、小茴香、花椒、胜红蓟和鬼针草5种植物乙醇提取物对褐飞虱若虫的触杀效果明显。辣椒、小茴香、花椒属于经济作物，本研究表明，这3种作物还具有开发为生物农药的价值。胜红蓟和鬼针草在华南地区分布广泛，易采集，植物资源丰富，具有开发成植物源杀虫剂的巨大潜力。
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