牛心朴等荒漠植物对棉铃虫的生物活性

选择了牛心朴等６种荒漠植物，利用其提取物对棉铃虫作了毒力和对生长和变态的影响等生物活性试验，结果表明５％牛心朴和大骆驼蓬的提取物对棉铃虫有较强的毒力，棉铃虫幼虫死亡率分别为１００％和５５％；同时，这两种提取物对棉铃虫的变态也有显影响，用１％的牛心朴和５％的大骆驼蓬饲料饲喂棉铃虫，幼虫死亡率分别为８５％和５５％，而羽化率为０。用牛心朴的不同提取物饲料饲喂棉铃虫。结果发现０．５％牛心朴的酸性提取物和

Bioactivities of Six Desert Plants Extracts to the Heliothis armigera Hitbner

Six desert plants were chosen to study their toxicity and effects on growth and metamorphosis to Heliothis armigera Hitbner. Artificial diet containing 5% water extracts of Cynanchum auriculatum Royle et Wight and Peganum harmala var. multisecta Maxim showing strong toxicity to the larvae and caused mortality of 100% and 55% respectively. Meanwhile the two extracts with the same dosage affects metamorphosis of the insect significantly. Artificial diet containing 1% water extracts of C.auriculatum and that containing 5% water extracts of P.harmala resulted in mortality of 85% and 55% and emergence rate of both 0 respectively. Different portions of the extracts of C.auriculatum were added to the diet to feed the larvae, the results shown that pH 3 and pH 10 portions of the extracts affected the larvae growth significantly.