Experiment in the Control of the Weeds in Sunflower Field with 17.5% Benazolin·quizalofop-P EC and its Safety

[Objective] The aim of the research was to screen out the medicaments that had better control effect on the weeds in sunflower field and better security.[Method] 7 treatments were designed with 17.5% Benazolin·quizalofop-P EC,Anxin,Naian,8.8% quizalofop-P-ethyl EC to control the weeds in sunflower field.And the plant damage rate,the preventing effect on single plant and the preventing effect on fresh weight were investigated.[Result] Pesticide injury to different degrees occurred in each treatment and the tender leaves of sunflower crimpled to be macrocephalic.The damage rate in the treatment of 8.8% quizalofop-P-ethyl EC was lowest,followed by treatment 1.Their average damage rates after applying drugs for 10 d in these 2 treatments were 2.24% and 9.94% respectively and the average damage rates showed decreasing trends.The preventing effect of single plant in treatment 5 after applying drugs for 30 d was best,followed by treatment 1 with discrepancy of 3.1 percent.The preventing effect on fresh weight in treatment 1 was best,followed by treatment 5,being 92.95% and 90.14% respectively.Mixed application of 17.5% Benazolin·quizalofop-P EC with herbicide antidote Anxin and Naian couldn't strengthen the security of sunflower.[Conclusion] 17.5% Benazolin·quizalofop-P EC should be suitable to be selected from the view of weed-control effect and security and f,8.8% quizalofop-P-ethyl EC should be suitable to be selected from the view of security.