苍耳等药用植物提取物对小菜蛾的拒食作用和产卵忌避效果

室内采用叶碟法,研究苍耳(Xanthium sibiricumPetril)等8种药用植物乙醇提取物对小菜蛾(Plutel-la xylostella)的拒食和产卵忌避活性。结果表明,苍耳(果实)、雷公藤(根)和商陆(根)乙醇提取物对小菜蛾4龄幼虫的取食均有较强的抑制作用,选择性拒食率分别为86.16%、49.06%和43.82%;非选择性拒食效果仍以苍耳(果实)提取物最好,达45.23%。选择性产卵忌避率以雷公藤(根)提取物为最高(69.52%),其次是苍耳(果实)和山苍树(枝叶)提取物,分别为62.50%和57.72%,雷公藤(根)、商陆(根)、窃衣(茎叶)和苍耳(果实)的非选择性产卵忌避作用均在77%以上。苍耳和雷公藤提取物在对小菜蛾的拒食和产卵忌避的各测试中,均表现较强活性。

Antifeedant and Oviposition Deterrent Effect of Extracts from Xanthium sibiricum and Other Medicinal Plants against Plutella xylostella L.(Lepidoptera:Plutellidae)

Effect of the antifeedant and oviposition deterrent of alcohol extracts from Xanthium sibiricum and other medicinal plants against diamondback moth (DBM,Plutella xylostella) were investigated by using leaf-disc method in laboratory.The extracts from X.sibiricum (fruit),Tripterygium wilfordii (root) and Phytolacca acinosa (root) showed significant antifeedant effect on the 4th instar larvae of DBM,with the choice-antifeedant rate of 86.16 %,49.06 % and 43.82 % ,respectively.Meanwhile,X.sibiricum (fruit) extract showed the best antifeedant activity against DBM,with 45.27 % of nonchoice-antifeedant rate.In the choice-test of oviposition deterrent,the extracts from T.wilfordii showed the best deterrent effect (69.52 %),and the next were X.sibiricum and Litsea cubeba (stem and leaf),with the choice oviposition deterrent rate of 62.50 % and 57.72 %.The extracts of T.wilfordii,P.acinosa,T.scabra and X.sibiricum showed significant deterrent effect on ovipisition of DBM adult in the nonchoice-test,and their oviposition deterrent rates were more than 77 %.The results suggested that using the secondary metabolites from X.sibiricum and T.wilfordii as insect pest behavior regulator was possible in integrated pest management.