title: Dissipation of mefenoxam residue in watermelon and soil under field conditions.
abstract: Mefenoxam is the systemic phenylamide fungicide, which is widely used in controlling phytophthora disease of tomato, cucumber, pepper and watermelon, etc. The dissipation behaviour of mefenoxam residues in watermelons and soils was studied. The whole watermelon, melon flesh and soil matrices of mefenoxam were analyzed by GC-NPD. At three different spiking levels mean recoveries and relative standard deviation from spiked samples in six replicated experiments for each matrix were in the range 89.6-98.2% and 1.5-8.1%, respectively. Under field conditions, mefenoxam dissipation rate was found to be faster in the whole watermelons than in the soils. The results showed that the half lives in whole watermelon and soil from Beijing were 3.9 and 10.0 days, respectively, and the half lives in whole watermelon and soil from Shanxi were 3.7 and 28.4 days.
authors.affiliation: Group of Pesticide Residue and Environmental Toxicology, Department of Applied Chemistry, College of Science, China Agricultural University, Beijing 100193, China. dliu@cau.edu.cn
authors.forename: Dan
authors.initials: D
authors.lastname: Liu
authors.forename: Dongmei
authors.initials: D
authors.lastname: Qin
authors.forename: Ran
authors.initials: R
authors.lastname: Ji
mesh_terms: D000409:Alanine / Q000031:analogs & derivatives* / Q000032:analysis; D002681:China; D002849:Chromatography, Gas; D029773:Citrullus / Q000737:chemistry*; D004784:Environmental Monitoring; D005659:Fungicides, Industrial / Q000032:analysis*; D006207:Half-Life; D010573:Pesticide Residues / Q000032:analysis*; D012015:Reference Standards; D012987:Soil / Q000032:analysis*; D012989:Soil Pollutants / Q000032:analysis*
chemical_list: D005659:Fungicides, Industrial; D010573:Pesticide Residues; D012987:Soil; D012989:Soil Pollutants; C473256:mefenoxam; D000409:Alanine