中文摘要：

采用小叶碟添加法观察经羟基马桑毒素处理后的粘虫中毒症状,并测定3龄、4龄和5龄粘虫的拒食活性。结果表明：①羟基马桑毒素作用后,粘虫表现为行动缓慢-昏迷-复苏-麻痹-失水中毒症状。②浓度大于1.00 mg.mL-1的羟基马桑毒素对3龄粘虫幼虫有明显的拒食作用,且随着药剂浓度的增大,拒食作用增强,最大拒食率达65.68%。③浓度为0.25~1.00 mg.mL-1的羟基马桑毒素可使4龄粘虫幼虫食量增加,当浓度为1.00~4.00 mg.mL-1时,有稳定的拒食作用,且在4.00 mg.mL-1时拒食作用最强。④浓度大于0.25 mg.mL-1的羟基马桑毒素对5龄粘虫幼虫有稳定的拒食作用。

英文摘要：

Toxic symptom and antifeedant activity of tutin were observed on the larvae of Mythimna separata with 3, 4 and 5 instar by leaf disk method. The results showed that the poisoning symptoms were slow in action, coma, recovery, paralysis, and dehydration on body surface. Antifeedant activity of tutin on the 3rd-instar larvae of M. separata was significant under the concentration of over 1.00 mg· mL-1 , and showed dosage-dependant pattern. The highest antifeedant rate was 65.68%. Which concentration is with- in 0.25-1.00 mg · mL-1 ,the feed intake of the 4th instar larvae of M. separata increased in the concen- tration range of 0.25-1.00 mg · mL-1 , antifeedant activity was steady in the concentration range of 1.00 -4.00 mg · mL-1 , and the maxium antifeedant activity was in concentration of 4.00 mg · mL-1. Stable antifeedant activity for the 5th instar larvae was in the concentration of over 0.25 mg · mL-1.