Residue Dynamics Of Propisochlor In Soil And Sweet Potato And Maize

Propisochlor is a kind of new ex- herbicide of the amide, mainly using for prevent the grain undergraduate course miscellaneous grass and part of broad-leaved and miscellaneous grass that influence soybean, corn, paddy rice and sweet potato in the field. The degradation of propisochlor in soil ,maize plant and soybean plant were studied for at the MRL level.The samples were extracted with petroleum and acetone, using petroleum to extract. The soybean plant and crop samples were cleaned-up with neutal aluminum oxide and activated carbon at a proper proportion. Firstly petroleum was used to wash the pillar, then we used the mixed liquor petroleum: ethyl acetate (9+1 V/V) to wash the pillar again, in order to eliminate impurity and pigment. The HP 6890 was equipped with u-ECD detector.Capillary column is DB-1 30m×0.25mm×0.25um. Carrier gas is N2. The Pressure of the carrier gas was 21.00psi. The split ratio was 1+5.The add level was 0.01 mg/kg, and1.00mg/kg, the recovery of propisochlorin soil,sweet potato plant,sweet potato,maize plant,maize was separately 72.2 %-98.3%, 80.4 % -101.8%, 78.5 %-112.9%, 81.6 % -102.9%, 82.5 %-103.8%, and C.V. was 2. 2-8. 7%. The recoveries were all in accordance with the requirements of the residue analysis. The LOD(limit of detection) of the method was 2.2×10^-10 g, and the LOQ(limit of quantification) for soil, sweet potato plant, sweet potato,maize plant and maize were all 0.01 mg/kg.The degradation of propisochlor in soil and sweet potato plant was studied by GC method through the 2-yr-2-field experiments in Shandong province and Zhejiang Province. The experiment results in Shandong province were as follows: in soil, the dynamic equation in 2006 was C=4.564e^0.1184t and the half-life was 5.9d, and the dynamic equation in 2007 was C=4.537e^0.1157t and half-life was 6.0d. In sweet potato plant, the dynamic equation in 2006 was C=76.035e^0.6853t and the half-life was1.01d, and the dynamic equation in 2007 was C =82.130e^0.7084t and half-life was0.98d. The experiment results in Zhejiang provincewere as follows: in soil, the dynamic equation in 2006 was C=3.981e^0.1017t, and half-life was 5.7d; and the dynamic equation in 2007 was C=3.981e^0.1017t, the half-life was 6.8d. In maize plant, the dynamic equation in 2006 was C=91.095e^0.7005tt and the half-life was0.99d, and the dynamic equation in 2007 was C =96.583e^0.7228t and half-life was0.96d. the experiment showed that propisochlor was not detected in sweet potato plant and soil at harvest time. The results showed that the degradation of propisochlor was faster in sweet potato plant than in soil.The degradation of propisochlor in soil andmaize plant was studied by GC method through the 2-yr-1-field experiments in Shandong province. The experiment in Shandong province: in soil, the dynamic equation in 2006 was C=16.080e^-0.104t and the half-life was 6.7d, and the dynamic equation in 2007 was C=196.134e^0.194t and half-life was3.6d. In maize plant, the dynamic equation in 2006 was C=34030.076e^1.071t and the half-life was0.65d, and the dynamic equation in 2007 was C =51021.378e^-1.141t and half-life was0.61d.the experiment showed that propisochlor was not detected in maize plant and soil at harvest time. The results showed that the degradation of propisochlor was faster in maize plant than in soil.