几种农药对甲霜灵光降解的影响

目的]研究溴虫腈、毒死蜱、氯氰菊酯、灭多威与甲霜灵混合后对其光解效应的影响。方法]以紫外灯为模拟光源,用一级动力学方程来描述光降解效应。结果]甲霜灵与供试农药等剂量混合时,溴虫腈和灭多威表现出光敏化降解效应;而毒死蜱和氯氰菊酯则表现为光猝灭降解效应。与不同剂量农药混合时,溴虫腈和氯氰菊酯对甲霜灵的光敏(猝灭)效率与剂量呈正相关、而毒死蜱和灭多威与剂量呈负相关。结论]供试农药对甲霜灵的光化学降解效应与剂量以及农药品种相关。

Effects of Four Kinds of Pesticides on Photodegradation of Metalaxyl

The objective of this study was to evaluate the photodegradation effects of chlorfenapyr,chlorpyrifos,cypermethrin and methomyl on metalaxyl.Methods] By using UV lamp to simulate different lighting conditions,the photodegradation effects of four insecticides on metalaxyl were simulated by first order kinetics equation.Results] The photolytic rates of the metalaxyl were accelerated with a ratio(1∶1) of metalaxyl to chlorfenapyr or methomyl.The photolysis rate of methomyl was slow down with chlorpyrifos or cypermethrin.When the ratio changed,the photosensitive efficiencies were in inverse ratio to its own dosage of chlorpyrifos and methomyl.Meanwhile,the photoactivate effect of chlorfenapyr or the photoquenching effect of cypermethrin was in positive correlation with dosage.Conclusions] The photodegradation effects of four insecticides on metalaxyl were related to dosages and types of insecticides.