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Triadimenol triadimefon (triadimefon) and its major metabolite (triadimenol) in the cabbage, soil residue analysis method has been improved by gas chromatography of their degradation dynamics, the final determination of residues and improve glucose soil organic matter content was studied the effect of its degradation. Soil samples extracted with acetone - water solution and extracted with dichloromethane purification, and concentrated under reduced pressure to both the simultaneous determination of triadimefon and its major metabolite triadimenol residues. Cabbage samples using methanol - water extraction, purification was extracted with methylene chloride, Florisil column purification using petroleum ether - ethyl acetate as eluent to further remove impurities and pigments collected eluent was concentrated under reduced pressure measuring maternal triadimefon and triadimenol metabolites. HP6890 gas chromatograph with μ-ECD detector, column HP5 30.0m × 320μm × 0.25μm capillary column and nitrogen as carrier gas, the use of temperature-programmed. Add concentration of the method to 0.05mg/kg, 0.20mg/kg, 1.00mg/kg, cabbage and soil of different levels triadimefon recoveries were 79.76% ~ 112.18%, 80.15% and 100.03%, the coefficient of variation was 4.41 % to 17.70%. Of different levels of its major metabolite triadimenol Cabbage and Soil recoveries were 80.2% to 98.89%, 80.01% and 99.50%, the coefficient of variation of 1.70% to 11.08%. The maternal in soil and cabbage minimum detectable concentration of 2.23 × 10 -4 mg / kg, and metabolites in soil and cabbage minimum detectable concentration of 1.25 × 10 -2 < / sup> mg / kg. By the Jilin Province 2003, 2004 a two-year field experiment, of triadimefon in soil and cabbage samples processed to 1500mL/hm 2 dosage for residual dynamic analysis. Degradation process in accordance with first-order kinetics mode C = C 0 e -kt . Two years in the soil degradation dynamics equations are: 2003, C = 0.6651e -0.048t , the half-life of 14.44d. 2004, C = 0.7939e -0.0574t , the half-life of 12.08d. In the the degradation dynamic equations of the cabbage in two years: 2003, C = 0.2376e -0.1489t , the half-life of 2.15d. 2004, C = 5.6514e -0.2096t , the half-life of 3.31d. The results show that: and triadimefon easily biodegradable in soil and cabbage, and cabbage degradation rate faster than in the soil. To evaluate the digestion rate triadimefon, cabbage, or soil belong to the degradation of pesticides. Simultaneous determination of the final residue of triadimefon on cabbage and soil. 2-year test results show that: the application of 20% to triadimefon EC, an application rate of 1500mL/hm 2 , and triadimefon were not detected in the harvest of cabbage, soil, triadimenol not detected in the cabbage, residues in the soil from 0.0287 to 0.0662mg/kg. According to the results of the study, reference to triadimefon in Cabbage and Soil Degradation Dynamics the recommended 20% triadimefon EC of cabbage reasonable amount not higher than 750mL/hm 2 , spraying 1 times. The triadimefon reference to the provisions of the mandatory national standards in China on the vegetables MRL value of 0.20mg/kg. Under this provision, it is recommended that our country triadimefon cabbage maximum residue limits tentative MRL of 0.20mg/kg. This paper also studied the glucose to improve soil organic matter content observed triadimefon degradation. The results showed that triadimefon faster rate of degradation in the soil of glucose added. The main reason is one of the main soil microbial degradation of pesticides in soil and soil organic matter in the soil microbes to reproduce the energy to
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