title: Photodegradation of bensulfuron-methyl on soil surface.
abstract: Photolysis of bensulfuron-methyl on soil surface was studied under sunlight and UV light. Seven photoproducts were isolated and characterised by spectroscopic methods. The major processes in the photolysis of bensulfuron-methyl in soil are cleavage of the sulfonylurea bridge, scission of the SO2NH bond and contraction of the sulfuronylurea bridge. The rates of photodegradation of bensulfuron-methyl on different soils followed first-order rate kinetics with half lives of 21.9, 28.4, 36.9, 59.2 and 47.2 h (UV) and 23.1, 27.5, 29.1, 38.9 and 33.8 days (sunlight) for vertisol, alluvial, alfisol, red and laterite soils, respectively. The differences in rates of photodegradation were dependent upon the soil texture and organic matter content.
authors.affiliation: Department of Plant Protection, Anhui Agricultural University, Hefei 230036, China. ybsi2002@yahoo.com.cn
authors.forename: You-Bin
authors.initials: YB
authors.lastname: Si
authors.forename: Yong-De
authors.initials: YD
authors.lastname: Yue
authors.forename: Huai-Man
authors.initials: HM
authors.lastname: Chen
authors.forename: Dong-Mei
authors.initials: DM
authors.lastname: Zhou
mesh_terms: D001673:Biodegradation, Environmental / Q000528:radiation effects; D008027:Light; D015394:Molecular Structure; D010573:Pesticide Residues / Q000737:chemistry / Q000378:metabolism*; D012987:Soil / Q000032:analysis*; D013453:Sulfonylurea Compounds / Q000737:chemistry / Q000378:metabolism*
chemical_list: D010573:Pesticide Residues; D012987:Soil; D013453:Sulfonylurea Compounds; C071475:methyl bensulfuron