Dynamics In Corn And Research On Mispe Of Acetochlor

Acetochlor is a selective Chloroacetamid herbicide used to control a wide spectrum of graminaceous weeds and grasses in corn and several other crops.The residue dynamics of acetochlor were studied in corn and soil.The residue dynamics accumulation and ultimately residue of acetochlor were detected by GC-μ-ECD respectively.On the level of 0.01-0.5mg/kg,the average recovery of acetochlor in soil,plant and seeds were 91.5%-97.8%,93.1%-103.7%,83.7%-89.7%,respectively.The limit of detection of acetochlor by GC-μ-ECD was 1.8×10^-11 g,The limit of quantification of Acetochlor by GC-μ-ECD was0.0039μg/kg and 0.009μg/kg.When high dosage 310ml/667m² 90%Acetochlor EC was applied in corn and soil,Two years' two-field test showed that residues of Acetochlor in soil and corn were 10.586-11.500 mg/kg, 2.749-3.048 mg/kg original respectively,the half-life of Acetochlor was 8.23-11.33d in soil, 7.35-7.65d in corn,respectively.The degradation procedure of Acetochlor can be described by first-order kinetics equation,C=C₀e^-kt.In soil,the dynamic equation in 2006 was C=9.4786e^-0.0677t (changchun) and C=11.296e^-0.0842t(heilongjiang),the dynamic equation in 2007 was 6.1483e^-0.0671t (changchun) and C=7.8115e^-0.0612t(heilongjiang).In the plant of corn,the dynamic equation in 2006 was C=2.5178e^-0.0906t and C=2.4292e^-0.0943t in 2007.The degradation rate was more than 90%in corn after 40 days,the results showed that Acetochlor is easy to degrade in corn and soil.The final residual concentration of Acetochlor in corn and soil was determined.Two years' two-field test showed that, when 310ml/667m²,155ml/667m² 90%Acetochlor EC was applied in corn and field;the final residue of Acetochlor in corn and soil fell below detectable limit.The result supported that the final residual concentration was no related to applying dosage.When the applying dosage increased,the residue of Acetochlor had no accumulation.Through comparing and analyzing,the superiority of traditional pre-treatment and MISPE technology were studied,the former used more solvent,longer time with greater waste and harmless. A novel highly selective sample cleanup procedure combining molecular imprinting and solid-phase extraction was developed for the simultaneous isolation of acetochlor from the soil.The recoveries were 88.3%-116.2%.It almost can meet the basic requirement of pesticide analysis.The novel pre-treatment method is more convenience,accurate and adoptable.