羊角拗对红火蚁的杀虫活性与行为抑制

Insecticidal Activity and Behavior Inhibition of the Red Imported Fire Ant by Strophanthus divaricatus

【目的】探讨羊角拗﹝Strophanthus divaricatus(Lour.)Hook.et Arn.﹞对红火蚁(Solenopsis invicta Buren)的致死作用和攀爬能力、行走能力等行为的影响。【方法】以水浸土壤处理对红火蚁进行防冶试验。【结果】羊角拗对中小型红火蚁工蚁具有良好的毒杀活性和行为抑制作用。土壤深度0~1.2、1.2~2.4、2.4~3.6 cm,经0.5 g羊角拗叶处理7 d后,小型工蚁死亡率分别为80.00%、60.00%、85.33%,中型工蚁死亡率分别为37.33%、34.67%、40.00%;经1 g羊角拗叶处理后,小型工蚁死亡率分别为50.67%、62.67%、88.00%,中型工蚁死亡率分别为33.33%、33.33%、40.00%;经2 g羊角拗叶处理后,小型工蚁死亡率分别为90.67%、88.00%、73.33%,中型工蚁死亡率分别为18.67%、28.00%、12.00%。【结论】羊角拗对红火蚁中小型工蚁均具有良好的致死作用,可以明显降低其行走能力和攀爬能力,而且对小型工蚁的杀虫活性和行为抑制能力较中型工蚁更强。羊角拗有望成为防治红火蚁的新材料。

【Objective】The study was conducted to explore the effects of Strophanthus divaricatus on the toxic activity,climbing ability and walking ability of Solenopsis invicta Buren.【Method】The toxic activity of S.divaricatus against the red imported fire ant(RIFA)was assayed with water immersion soil treatment method.【Result】S.divaricatus had good toxic activity and behavioral inhibition on small and medium RIFA workers.After treated with fresh smashed leaves of S.divaricatus(0.5 g),the mortality rates of small RIFA workers with soil depths of 0-1.2 cm,1.2-2.4 cm and 2.4-3.6 cm were 80.00%,60.00% and 85.33%,and those of medium RIFA workers were 37.33%,34.67% and 40%.After treated with fresh smashed leaves of S.divaricatus(1 g),the mortality rates of small RIFA workers were 50.67%,62.67% and 88% respectively,and those of medium RIFA workers were 33.33%,33.33% and 40%.After treated with fresh smashed leaves of S.divaricatus(2 g),the mortality rates of small RIFA workers were 90.67%,88%,73.33%,and those of major RIFA workers were 18.67%,28%,12%,respectively.【Conclusion】S.divaricatus has a good lethal effect on small and medium RIFA workers and it can significantly reduce their walking ability and climbing ability.It has stronger insecticidal activity and behavioral inhibition on small RIFA workers than that on medium RIFA workers.S.divaricatus is expected to become a new material for the control of RIFA.