农药的生态安全特性指标Q方程的研究

以北京地区冬小麦麦田的麦长管蚜Macrosiphumavenae (Fabricius)与七星瓢虫Coccinellaseptem punctataLinnaeus幼虫为实验材料 ,选择抗蚜威、乐果、氰戊菊酯 3种常用农药 ,改传统的死亡几率值为存活几率值 ,得到 6条剂量对数—存活几率值回归直线和 6个方程。定义特定农药的不同剂量下害虫与天敌存活率比值叫生态安全系数Q。利用Origin 5.0软件上机对 3个Q(x)方程绘图 ,直观地显示了不同农药种类的差异。田间实验证明 ,防治前后的害虫益虫比值与Q方程计算值基本吻合。因此可能有较大的实用价值

A study on the Q equation of pesticide ecological safety coefficient.

Toxicities of three insecticides, pirimicarb, dimethoate and fenvalerate, to both English grain aphids, Macrosiphum avenae (Fabricius), and larvae of lady beetle, Coccinella septempunctata Linnaeus, collected from winter wheat field were assayed using Potter spraying method in Beijing, and six regression lines(equations) between probits of survival rate and logarithms of dose were obtained. Ecological safety coefficient( Q ) was calculated by the survival rate of aphids divided by survival rate of lady beetle.Three curves of Q ( x ) equations, drawn by scientific software, Origin 5\^0, indicated the effects of three insecticides different were distinctly. Experiments in field proved that the results calculaed according to Q equation were close to actual ratio of pest and its natural enemy survivals.