title: Persistence of herbicide fenoxaprop ethyl and its acid metabolite in soil and wheat crop under Indian tropical conditions.
abstract: The persistence of fenoxaprop ethyl {Ethyl (RS)-2-[4-(6-chloro-1,3-benzoxazol-2-yloxy) phenoxy] propionate} herbicide and its active metabolite fenoxaprop acid was investigated in soil and wheat crop. Fenoxaprop acid was prepared by alkaline hydrolysis of fenoxaprop ethyl. A HPLC method was developed in which fenoxaprop ethyl herbicide and its acid metabolite showed sharp single peak at 6.44 and 2.61 min respectively. The sensitivity of the method for ester and acid was 2 and 1 ng respectively with limit of detection of 0.1 and 0.05 μg mL(-1). The recovery of fenoxaprop ethyl and fenoxaprop acid from soil, wheat straw and grain ranged between 73.8-80.2%. In a field experiment fenoxaprop ethyl (Puma super® 10 EC) when applied to wheat crop at the rate of 120 g and 240 g a.i. ha(-1) as post emergence spray, fenoxaprop ethyl converted to fenoxaprop acid. Residues of fenoxaprop ethyl and acid dissipated in soil with a half-life of 0.5 and 7.3 days, respectively. At harvest no detectable residues of fenoxaprop ethyl or acid were observed in soil, wheat grain and straw samples.
authors: Division of Agricultural Chemicals, Indian Agricultural Research Institute, New Delhi, India. shashi.sbsagch@gmail.com
authors: Shashi B
authors: SB
authors: Singh
authors: Tapas K
authors: TK
authors: Das
authors: Gita
authors: G
authors: Kulshrestha
mesh_terms: D002851:Chromatography, High Pressure Liquid; D004784:Environmental Monitoring; D006540:Herbicides / Q000032:analysis* / Q000378:metabolism; D007194:India; D010080:Oxazoles / Q000032:analysis* / Q000378:metabolism; D011422:Propionates / Q000032:analysis* / Q000378:metabolism; D012987:Soil / Q000032:analysis; D012989:Soil Pollutants / Q000032:analysis* / Q000378:metabolism; D014908:Triticum / Q000737:chemistry* / Q000378:metabolism; D014329:Tropical Climate
chemical_list: D006540:Herbicides; D010080:Oxazoles; D011422:Propionates; D012987:Soil; D012989:Soil Pollutants; C416661:fenoxaprop ethyl