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In this paper, pendimethalin pendimethalin in potato tubers and plant residues in the soil and soil adsorption characteristics determined. Acidic methanol extraction, liquid-liquid distribution of petroleum ether Florisil column purification, quartz capillary column GC-ECD and GC-MS-SIM analysis techniques, pendimethalin in potato tubers and plants, soil The residual dynamic, degradation rule and eventually residues were analyzed by HPLC. The minimum detectable amount of GC-ECD 5x10 -12 g; minimum detectable concentration of 0.001mg · kg -1 . The method added concentration 0.01mg · kg the -1 0.1mg · kg -1 1.0mg · kg -1 , each spiked level recovery rate in 2002 of 79% to 125.5% (potato tubers), 78% to 103.50% (potato plants), 80% to 92.8% (soil); 71% to 105% (potato tubers) in 2003, 75% to 103% (potato plants), 91.3% to 106% (soil). GC-MS-SIM analysis method minimum detectable amount of 1 × 10 -11 g; minimum detectable concentration of 0.001mg · kg -1 , each add a level of recovery the rate was 81% in 2002 to 87% (potato tubers), from 90% to 99% (potato plants), 89.3% to 98% (soil); 76.7 percent in 2003 to 97.7% (potato tubers), 72% to 93.7 % (potato plants), 83.7% to 109.3% (soil). Potato Tanaka after sowing before spraying 33% pendimethalin EC 2475g.hm -2 (active ingredient) two years the two test results show that: pendimethalin residues in potato plants lower degradation soon. The 2002 Changchun test point 14d residues for 0.024mg · kg -1 , Jinan test point 14d is 0.01mg kg -1 . The 2003 Changchun test point 21d residues for 0.035mg · kg -1 , Jinan test point 21d is 0.09mg kg -1 . Pendimethalin in 2002 in the original deposition amount of the two different soil, Changchun 11.22mg · kg -1 , Shandong 2.12mg · kg -1 . 2003 of Changchun original deposition amount 2.98mg · kg -1 90d degradation rate of 84%; Shandong 6.96mg · kg -1 , 75d degradation rate of 94% . Pendimethalin in soil degradation need to use C t = C the 0 t -k that equation. Plants in the first sampling time (2002), spraying the 14d and 21d (2003 years), and therefore establish the dynamic equations of Field Degradation of no practical significance. 2002, pendimethalin in soil degradation dynamic equations Changchun: the C t = 4.252t -0.4467 r = -0.9052, half-life (T 1 / 2 ) 1.6d; Jinan: the C t = 1.547t -0.2041 r = -0.8052,3.4 d; 2003 in soil degradation The dynamic equation Changchun: the C t = 1.7227t 0.2318 r = -0.9495, T 1/2 3.0d; Jinan: C < sub> t = 3.2707t -0.3734 , r = -0.9238, T 1/2 1.8d. Short, pendimethalin, whether in potato plants, or in the soil are all readily biodegradable pesticides. Simultaneous determination of the final residues of pendimethalin in potato and soil. The field trial program in 2003 to increase the determination of the the edible period tubers of potato before final harvest sometimes dug edible. Be seen from the measured data, the two places, whether high-dose or low-dose pesticide, pendimethalin content in potato tubers are low
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