茶树根系吸收对茶叶中农药残留的影响

Effect of root absorption properties of tea plant on pesticide residues in tea

用田间盆栽的方法研究了茶树通过根系吸收农药对茶叶中乐果、乙硫磷、三氯杀螨醇和三氟氯氰菊酯残留的影响。结果表明 ,在各农药添加浓度为 10 mg/ kg的土壤中培养 7个月后 ,土壤和茶叶中均未检出乐果和三氟氯氰菊酯 ,而乙硫磷和三氯杀螨醇在土壤中的残留量仍有 3mg/ kg～ 4 m g/ kg,茶叶中的乙硫磷和三氯杀螨醇残留分别为 0 .0 8m g/ kg和 0 .15 m g/ kg,并且茶叶中残留浓度随土壤中残留量的增加而上升。

The effect of root uptake of pesticides by plant from soil on the pesticide residues in tea was investigated in field conditions. After 7 months of incubation, no detectable amount of dimethoate and cyhalothrin both in soil and tea was found,and the concentration of ethion and dicofol was 2.81 mg/kg and 3.98 mg/kg in soil,whereas the concentration of ethion and dicofol in tea was 0.08 mg/kg and 0.15 mg/kg,respectively,while the initial concentration of each pesticide in soil was 10 mg/kg, The amount of ethion and dicofol found in tea increased with the increasing concentration in soil,which suggested that the pesticides in soil might contribute to the pesticide residues in tea.