近 5年多来 ,棉田杂草防治技术有了很大的变化 :第一种地表除草剂嘧草硫醚被商品化 ,然后是转基因抗溴苯腈和抗草苷膦棉花品种很快被棉农采用。 1 999年 ,北卡罗那州 1 3%的棉田、弗吉尼亚州 30 %的棉田种植了抗溴苯腈棉。东南部其余四个州 1 %的棉田种植抗溴苯腈 ,东南部的六 Over the past five years or so, cotton weed control technology has undergone great changes: the first surface herbicide pyrithrin is commercialized, and then the transgenic anti-bromoxynil and anti-glyphosate cotton varieties are quickly cotton farmers use. In 1999, 13% of cotton fields in North Carolina and 30% of cotton fields in Virginia were planted with resistance to bromoxynil. In the remaining four states in the southeast, 1% of the cotton fields are resistant to bromoxynil and six to the southeast