Study On Residue Analytical Methods Of Cyhalofop-butyl In Different Matrices And Its Degradation In Plant

The Cyhalofop-butyl is a new herbicide for rice which has a high degree ofsecurity,therefore the more popular varieties of the domestic registration. In recent years,research on the efficacy and weeding mechanism of the Cyhalofop-butyl reported more,however, the ester aqueous emulsion of10%Cyhalofop-butyl Residue behavior in theplants has not been reported yet.This paper by ester water emulsion of10%Cyhalofop-butyl Residue behavior in plants, and provide a basis to guide the rational useof the aqueous emulsion of10%Cyhalofop-butyl and to ensure the quality and safety ofagricultural products, The main findings are as follows:1. Establishment of the Cyhalofop-butyl residue analysis methods in differentMatrices samplesWater samples extracted with dichloromethane three times, Acetonitrile constantvolume, By HPLC-of UV detection, Concentration in0.005mg/L-0.1mg/L within, TheCyhalofop-butyl The recoveries were82.96%-90.16%,Coefficient of variation between3.06%-9.18%,The minimum detectable concentration was0.004mg/L, Soil and rice firstwith acetonitrile mechanical oscillation extraction, and then clean up by Florisil column.With40mL of hexane/acetone (V/V=9/1) leaching purification, acetonitrile, constantvolume, by HPLC-UV determination, Added concentration0.05mg/kg-1.0mg/kg range,then Cyhalofop-butyl add recoveries were between80.94%-93.76%.Its coefficient ofvariation was3.26%-6.33%, the final minimum detectable concentration were0.08mg/kg,0.04mg/kg. Plants and rice chaff extracted with acetonitrile, through GCB column, purifyit with6mL acetonitrile/toluene (V/V=3/1) leaching, constant volume with acetonitrile,by HPLC-UV determination, added concentration0.1mg/kg-1.0mg/kg range, when theCyhalofop-butyl recoveries of between77.90%-94.52%, the coefficient of variation of3.29%-7.76%, the minimum detectable concentration was0.08mg/kg. The methodselected in full compliance with the technical specifications and requirements for pesticideresidue analysis and detection.2.Cyhalofop-butyl in the degradation of the dynamic in plantCyhalofop-butyl digestion in rice plants In Hefei, Zhengzhou, and Zhanjiang are inline with the first order eqution Ct=C0e-kt. Cyhalofop-butyl numerical elimination half-lifewere0.71d,0.73d and1.82d；.In the natural environment, Cyhalofop-butyl can be rapid degradation, the residue compared to a short.