连翘挥发油对两种烟草仓储害虫的毒杀作用

为开发新型烟草仓储防护剂，研究连翘果实挥发油的化学成分及其对烟草仓储害虫的杀虫活性。通过GC-MS分析了连翘果实挥发油的化学成分，运用柱色谱和核磁共振方法分离并鉴定化合物，通过熏蒸、触杀试验测试挥发油及单体成分活性。结果表明，连翘挥发油对烟草甲和赤拟谷盗熏蒸活性的LC₅₀值分别为8.94和7.68 mg/L；触杀活性的LD₅₀值分别为23.66和30.13 μg/头。单体化合物中，4-萜品醇对烟草甲的熏蒸和触杀毒性最强（LC₅₀值为6.90 mg/L；LD₅₀值为8.62 μg/头）。另外，α-蒎烯，γ-萜品烯和4-萜品醇对两种仓储害虫均具有较好的熏蒸和触杀活性。因此，连翘挥发油及其单体化合物对烟草甲和赤拟谷盗均具有一定防治作用。

Insecticidal Activities of the Forsythia Suspensa Essential Oil Against Two Tobacco Storage Insects

Bioactivity screening was conducted in order to develop new botanical pesticides against tobacco storage pests. The essential oil obtained from the fruits of Forsythia suspensa was investigated by GC-MS. A total of 18 components representing 94.30% of the oil were identified and the main compounds in the oil were found to be α-pinene (63.72%), b-terpinyl acetate (7.47%), 4-terpineol (6.67%), 3-isopropyltoluene (3.54%) and γ-terpinene (2.54%). It was found that the essential oil exhibited strong fumigant toxicity against Lasioderma serricorne and Tribolium castaneum adults with LC₅₀ values of 8.94 and 7.68 mg/L air. Meanwhile, the essential oil exhibited contact toxicity against T. castaneum and L. serricorne adults with LD₅₀ values of 23.66 and 30.13 μg/adult. Among the three individual compounds, 4-Terpineol showed the strongest fumigant and contact activities (LC₅₀=6.90 mg/L; LD₅₀=8.62 μg/adult) against L. serricorne. Meanwhile, α-pinene, γ-terpinene and 4-terpineol exhibited strong bioactivities against T. castaneum. The results indicated that the essential oil of F. suspensa and its isolated compounds have the potential to be developed into natural insecticides for controlling insects in stored tobacco.