降解菌株DG-S-01对菜薹和土壤中3种拟除虫菊酯类农药降解动力学的影响

通过室内盆栽和大田小区试验,测定了降解菌株苍白杆菌Ochrobactrum sp.DG-S-01对高效氯氰菊酯、高效氯氟氰菊酯和氰戊菊酯在菜薹和土壤中的降解动力学的影响。结果表明,降解菌株DG-S-01可有效去除菜薹和土壤中3种供试农药的残留,且降解过程符合一级动力学模型,降解半衰期(t1/2)与未经该菌株处理的对照相比缩短1.5～53.2 h。在菜薹中,3种农药的残留量均随降解菌处理时间的延长而降低,处理72 h后,高效氯氰菊酯和高效氯氟氰菊酯的残留量均小于0.5 mg/kg的水平。在土壤中,高效氯氰菊酯和高效氯氟氰菊酯残留量也随降解菌处理时间的延长而降低,处理72 h后,其残留量小于1 mg/kg的水平;而氰戊菊酯在土壤中的残留量则呈现先上升后下降的趋势。对照菜薹和土壤中3种农药的残留量均明显高于喷施降解菌株的处理。

Degradation kinetics of three pyrethroid insecticides by strain DG-S-01 in flowering Chinese cabbage and soil

Degradation kinetics of beta-cypermethrin,lambda-cyhalothrin and fenvalerate by Ochrobactrum sp.strain DG-S-01 in flowering Chinese cabbage(Brassica campestris L.sp.) and soil were investigated by pot and field plot experiments.The results showed that strain DG-S-01 could effectively degrade these pyrethroid residues in flowering Chinese cabbage and soil.The degradation followed first-order kinetics and the half lives(t1/2) shortened by 1.5-53.2 h compared with control.The results also indicated that the py...