Residue Analysis Methods And Degradation Dynamics Research Of Probenazole In Rice

Probenazole is one kind of bactericide for the prevention of Rice blast,it is to used widely in China.In this paper,residue analysis methods and dynamics of probenazole have been studied for knowing residue status after used in rice field and estimating the safety.The results will provide evidences for using pesticides rationally, guiding agriculture production and insuring agriculture products quality safety and environment safety.Residue analysis methods research on probenazole,a classic gas chromato graphic method has been used in rice plant,grain,soil and water,different methods have been compared by experiments.The results show,rice plant,grain,soil and water sample were extracted with acetonitrile,followed by concentrating and. filtrating,probenazole was analyzed by S-PFPD,the average recoveries of rice plant ranged from 89.61%to 96.15%,the C.V was between 4.20%and 8.72%.the average recoveries of rice grain ranged from 90.42%to 96.37%,the C.V was between 4.86% and 8.13%,the average recoveries of soil ranged from 94.53%to 97.36%,the C.V was between 3.18%and 4.39%,the average recoveries of water ranged from 87.78% to 94.20%,the C.V was between 4.27%and 5.19%.The limit of detector was 0.04mg/Kg.The pre-treatment method of samples and the chromatographic conditions of the analysis were critically examined in experiment,the above methods were confirmed for its easier,exacter,faster and being better purification effect.Through the field trial investigation on probenazole residue in rice,the results indicated that,the degradation dynamic of probenazole residue is different with experiment environment.When the applied bactericide concentration is 8000g.ai/ha, the degradation dynamic equation is y=3.0635e^-0.268tin rice plant in ChangSha 2004, the half-time could be calculated and the value is 2.6d respectively from the above equation.the degradation dynamic equation is y=2.6793e^-0.279trespectively in rice plant in ChangSha 2005,the half-time could be calculated and the value is 2.5d respectively from the above equation.