斑鸠菊精油对红火蚁的熏蒸活性研究

为探讨斑鸠菊精油化学成分及防治红火蚁的效果，采用水蒸馏法提取斑鸠菊的精油，通过气相色谱−质谱联用（GC−MS）分析精油的化学成分，运用熏蒸法测定该精油对红火蚁的熏蒸活性及亚致死活性。结果表明：黄色透明的斑鸠菊精油具有浓郁香气，提取率为1.23%；该精油中鉴定出了15种化学成分，其中β−香树脂醇和α−香树脂醇为其主要化学成分，相对质量分数分别为36.98%和23.00%；该精油对红火蚁的灭杀活性随着处理时间和处理浓度的增加而增加，当处理浓度为200 μL/L和100 μL/L时，分别在处理4 h和6 h后致死率达到最高（100%）；当处理浓度为200 μL/L时，分别在LT₅和LT₁₀处理时间后挑取活蚁正常培养，活蚁分别在6 h和5 h内全部死亡。由此可见，斑鸠菊精油对红火蚁具有极高的熏蒸活性，且造成的伤害是不可逆的。

The Fumigation Activity of Essential Oil from Vernonia esculenta Against Red Imported Fire Ant

In this study, the chemical composition analysis of essential oil of Vernonia esculenta(VE) and its effect on the control of red imported fire ant(RFIA) were studyed. The essential oil of VE was extracted by water distillation and the compounds were analysed by GC−MS, then the fumigation activity of VE against red imported fire ant was tested. The result showed that the yellow and transparent essential oil with strong aroma was extracted from VE by water distillation, and the extraction rate of VE reach about 1.23%. And 15 compounds were identified, the major constituents of VE are α−Amyrin and β−Amyrin with 23.00% and 36.98%, respectively. The insecticidal activity of the essential oil against RFIA increased with treatment time and concentration increasing , and the highest mortality rate was 100% after 4 h and 6 h treatment at the concentrations of 200 μL/L and 100 μL/L , respectively. The alive RFIAs were selected and cultured normally after teratment LT5 and LT10 at 200 μL/L concentration, while all RFIAs died during 6 h and 5 h respectively. The essential oil of VE has high fumigation activity against red imported fire ants, and the damage is irreversible. This study can provide a new way against RFIA.