磺酰脲类除草剂具有广谱性 ,用量极低 ,选择性强和低的急慢性毒性。这类除草剂抑制乙酰乳酸合成酶 ,阻止支链氨基酸缬氨酸、亮氨酸、异亮氨酸的生物合成 ,导致植物细胞停止分裂和生长。作物的选择性由耐性作物的快速钝化代谢而引起。该类除草剂在土壤中降解是通过脲桥水解和微生物降解的共同作用 ,而且除草剂在酸性条件比碱性条件水解迅速 Sulfonylurea herbicides have a broad spectrum, low dosage, high selectivity and low acute and chronic toxicity. This class of herbicides inhibits acetolactate synthase, preventing the biosynthesis of the branched-chain amino acids valine, leucine, and isoleucine, resulting in the plant cells ceasing to divide and grow. Crop selectivity is caused by the rapid passivation of tolerant crops. The degradation of these herbicides in soils is through the interaction of urea bridge hydrolysis and microbial degradation, and the herbicides hydrolyze rapidly under acidic conditions than under alkaline conditions