从农田使用除草剂以来,其每亩用药量为几十克至数百克之间,大部分都要用100克左右,才能达到灭草目的。七十年代末,大量具有除草活性的磺酰脲类化合物申请了专利,这些药剂具有非常高的除草活性,毒性低,超低用量。首先出现的是用于麦田的氯磺隆(DPX-W4189),每亩用药量仅为0.2—2克,即可防除麦田大多数阔叶杂草和某些禾本科杂草如苋、藜、(?)麻、苍耳、田蓟、繁偻、扁蓄、蒲公英、稗草、马唐、狗尾草、看麦娘等,对麦类作物十分安全。以后这一类的除草剂新品种不断涌现,如用于禾本科作物田的甲磺隆(DPX-T 6376)、阔叶净 Since the use of herbicides from farmland, the dosage per mu for a few grams to hundreds of grams, most of them have to use about 100 grams, in order to achieve the purpose of extinguishing grass. The late seventies, a large number of herbicidal activity sulfonylureas patented, these agents have a very high herbicidal activity, low toxicity, low dosage. The first is the emergence of chlorsulfuron (DPX-W4189) for use in the field of wheat with a dosage of only 0.2-2 grams per acre to control most broadleaf weeds and certain grass weeds such as amaranth, quinoa, (?) Hemp, cocklebur, thistle, bream, flat storage, dandelion, barnyard grass, crabgrass, Setaria, Amanita and so on, is very safe for wheat crops. In the future, new varieties of herbicides emerge, such as metsulfuron-methyl (DPX-T 6376) for gramineous crop fields,