Fan Zhi-Jin, Ai Ying-Wei, Qian Chuan-Fan, Li Zheng-Ming
National Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin 300071, China.
J Environ Sci (China). 2005;17(3):399-403.
Monosulfuron was developed for weed control in the field of wheat (Triticum, aestivum L.) and millet (Panicum miliaceum L.) with the application rate ranging from 15 to 60 g ai/hm2. Herbicidal activity of monosulfuron was evaluated systematically by bioassay using maize (Zea mays L.) taproot as indicator and weed fresh weight of Acalypha australis L. and Echinochloa phyllopogon. Maize CAU 3138 was the most tolerant cultivars to monosulfuron with IC50 (concentration of 50% inhibition) of 85 microg/kg, Yedan 13 was one of the most sensitive cultivars to monosulfuron with IC50 of 6.4 microg/kg. Monosulfuron inhibited the growth of Acalypha australis L. strongly comparing with that of Echinochloa phyllopogon. Monosulfuron was a good acetolactate synthase (ALS) inhibitor in vitro, the I50 (50% of inhibition) of monosulfuron, chlorsulfuron, tribenuron-methyl and nicosulfuron for CAU 3138 were 32, 2, 19 and 26 nmol/L respectively, for Yedan 13 the I50 were 15, 3, 17 and 65 nmol/L respectively. In vivo ALS inhibition occurred only in higher concentration of 4 sulfonylurea herbicide tested. Comparison study of this test indicated that the mode of action of monosulfuron was the same as that of other sulfonylurea herbicides such as chlorsulfuron, tribenuron-methyl and nicosulfuron, they were all inhibitors targeted at the ALS.
单嘧磺隆是用于小麦（普通小麦）和谷子（粟）田除草的药剂，施用量为15至60克有效成分/公顷。以玉米（玉米）主根为指标，采用生物测定法，以铁苋菜和畦畔莎草的杂草鲜重为指标，系统评价了单嘧磺隆的除草活性。玉米品种CAU 3138对单嘧磺隆耐受性最强，半数抑制浓度（IC50）为85微克/千克，掖单13是对单嘧磺隆最敏感的品种之一，IC50为6.4微克/千克。与畦畔莎草相比，单嘧磺隆对铁苋菜的生长抑制作用更强。单嘧磺隆在体外是一种良好的乙酰乳酸合成酶（ALS）抑制剂，单嘧磺隆、氯磺隆、苯磺隆和烟嘧磺隆对CAU 3138的半数抑制浓度（I50）分别为32、2、19和26纳摩尔/升，对掖单13的I50分别为15、3、17和65纳摩尔/升。在体内，只有在所测试的4种磺酰脲类除草剂浓度较高时才会发生ALS抑制作用。该试验的比较研究表明，单嘧磺隆的作用方式与氯磺隆、苯磺隆和烟嘧磺隆等其他磺酰脲类除草剂相同，它们都是针对ALS的抑制剂。
