中文摘要：

基于分子拓扑邻接矩阵的分子形状指数^mK及电性拓扑状态指数Ef，计算了29种取代芳烃的Kier指数．通过多元线性回归法，建立了拓扑指数与取代芳烃抑制黄瓜种子发芽率的毒性pC50的定量结构-活性相关模型，该模型相关系数R^2为0．874，标准偏差S为0．116，计算值与实验值基本吻合．经Jackknife逐一剔除法检验，所建模型具有良好的预测能力与稳健性．利用该模型探讨了取代芳烃抑制黄瓜种子发芽的毒性机理，证明这些化合物属于极性麻醉或反应性毒物．

英文摘要：

Kier＇s shape indices of 29 substituted aromatic molecules were calculated based on the adjacency matrix of the molecular topology and the electrotopological state indices in this paper. A quantitative structure-activity relationship was developed between the topological indices and the inhibition phytotoxicity （pC50） of 29 benzene deriva- tives on seed germination rate of cucumis sativus using multiple linear stepwise regression. The correlation coefficient and the standard deviation of this model are 0. 874 and 0. 116, respectively. The calculated values of the pC50 based on this model is in accordance with their corresponding experimental values. It is verified, using leave-one- out of the Jackknifed method, that the model is predictable and robus. On the basis of the model, the mechanism of the toxicity of aromatic molecules on seed germination to polar narcotic and reactivity toxicants. rates has been studied. It shows that these compounds belong