中文摘要：

2000—2002年,延边地区稻田发现了抗磺酰脲类除草剂苄嘧磺隆的生态型慈姑。与敏感型相比,苄嘧磺隆、吡嘧磺隆对抗药性慈姑乙酰乳酸合成酶活性的抑制效果很低,抗药性慈姑乙酰乳酸合成酶对苄嘧磺隆和吡嘧磺隆的抗性系数（RI50/SI50）值分别为57.3、20.0,并存在交互抗药性。确认抗药性生态型慈姑的抗药性是由其乙酰乳酸合成酶对苄嘧磺隆、吡嘧磺隆毒性反应钝化所致。

英文摘要：

The sulfonylurea（SU） resistant biotypes of S. sagittrifolia were found in the paddy fields in Yanbian region in 2000 and 2002. The inhibiting effect of the SU on acetolactate synthase activity（ALS） of SU resistant biotypes is lower than susceptive biotypes. The coefficient（RI50/SI50） of resistance to bensulfuron and to pyruzasulfuron in resistant biotypes was 57.3 and 20,0 respectively. It has been found that the cross-resistance occurred between bensulfuron and pyruzasulfuron. The research results suggest that SU-resistant for sulfonylurea herbicides was dulled to ALS of SU-resistant biotypes.