测试结果表明 :苦皮藤乳油对菜粉蝶的卵没有直接杀伤作用 ,但卵孵化出的幼虫却有较高的死亡率。对 1～ 5龄不同龄期的菜青虫进行胃毒测试 ,苦皮藤素LC50 分别为 2 4.78mg/kg,72 .5 5mg/kg,1 2 4.35mg/kg,32 1 .2 1mg/kg,1 2 40 .42mg/kg。田间药效试验表明 ,一次施药 5 0mg/kg和 1 0 0mg/kg的苦皮藤乳油对菜青虫的防效差异不显著 ,但保产效果明显不同。研究结果表明 ,苦皮藤乳油防治菜青虫的有效浓度以 5 0mg/kg为宜。 Test results show that: bitter vinegar EC on cabbage butterfly eggs have no direct killing effect, but eggs hatch larvae have a higher mortality rate. The gastric toxicity test was conducted on Pieris rapae from different ages of 1 to 5 instar larvae. The LC50 of cephalexin were 2. 4.78mg / kg, 72.55mg / kg, 12.435mg / kg, 32.1.2mg / kg , 1 2 40 .42 mg / kg. The field efficacy test showed that the control effect of Eupatorium nudiflorum at 50 mg / kg and 100 mg / kg was not significant, but the yield-protected effect was obviously different. The results showed that the effective concentration of bitter vinegar EC against Pieris rapae 50mg / kg is appropriate.