Studies On The Resistant Mechanism Of Alopecurus Japonicus(S.) To Chlorsulfuron And Metsulfuron-methyl

The resistance of Alopecurus japonicus Steud. to chlorsulfuron and metsulfuron-methyl was studied in 2 levels: bioassay and biochemistry.Bioassay was conducted to verify the herbicide efficacy on different populations collected from Jiangsu and Zhejiang provinces and to reveal current herbicide resistant status on the species tested. In experiments I and II, it was found that control rate of all species was highly accordant among the tests. The ICso of all treatments were higher than the rate recommended. Almost all treatments survived after 3 weeks, only the most susceptible species was killed mostly after 3 weeks in experiments I and III. The controlling effect of chlorsulfuron and metsulfuron-methyl showed that the tested Alopecurus japonicus might have evolved herbicide resistance.The ALS enzyme extracted from the tested Alopecurus japonicus should be tested within 24 hours after extraction to ensure a reliable result. The ALS activities in different populations were remarkably lower when treated with the herbicides, still remained the trend as the higher the concentration of herbicides, the lower the ALS's activity. The controlling effect of chlorsulfuron and metsulfuron-methyl also showed that the tested Alopecurus japonicus might have evolved herbicide resistance.The absorption peak of 3-hydroxy-2-butanone-creatine-l-naphthol compound extracted from Alopecurus japonicus Steud., Avena fatua L., Echinochloa crus-galli L., and Chenopodium album L. were confirmed as the former three at 520nm, and the last at 530nm.