The comparative activity of sesquiterpene lactones from Xanthium sibiricum, the main active ingredient L-Ⅱ of which was 413,513- epoxyxanthatin- 1 α, 4α- endoperoxide, and alkaloids from Macleaya cordata (MacSC), main active ingredients of which was sanguinarine and chelerythrine, against three insect pests, including diamondback moth Plutella Jcylostella (Lepidoptera: Plutellidae), peach aphid Myzus persicae (Hemiptera: Aphididae) and mustard aphid Lipaphis erysimi (Hemiptera: Aphididae), were studied in laboratory. The results s...