【摘要】 采用菌落生长速率法测定了2005年从云南、贵州、山东烟区病株上分离到的38个烟草黑胫病菌Phytophthora nicotianae Breda de haan var.nicotianae Waterhouse菌株对两种保护性杀菌剂的敏感性。结果表明:百菌清(B)对各参试菌株的EC50值在2.33～49.47μg/mL之间,平均值为9.35(±2.77)μg/mL;代森锰锌(Z)对各参试菌株的EC50值在3.51～82.05μg/mL之间,平均值为10.59(±4.06)μg/mL。B及Z对除XR001外的37个菌株的EC50值分别呈连续的双峰(主峰明显)和单峰频次分布;B对构成敏感性正态频次分布主峰的30个菌株的EC50均值5.99(±0.78)μg/mL和Z对组成连续敏感性正态频次分布的37个菌株的EC50均值8.66(±1.09)μg/mL可分别作为烟草黑胫病菌对B及Z的敏感性基线。更多还原

【Abstract】 The sensitivities to chlorothalonil(B) and mancozeb(Z) of 38 strains of Phytophthora nicotianae Breda de haan var.nicotianae Waterhouse collected from tocacco plants in Yunnan,Guizhou,Shandong China in 2005 were determined with the method of colonial growth-rate.The results showed that the EC50 values of B and Z to all the strains ranged from 2.33 μg/mL to 49.47 μg/mL and from 3.51 μg/mL to 82.05 μg/mL,respectively;and the EC50 mean values were 9.35(±2.77) μg/mL and 10.59(±4.06) μg/mL,respectively.The frequency distributions of EC50 values of B and Z to 37 strains except of XR001 were bimodal with evident main peak and unimodal,respectively.The EC50 mean value (5.99±0.78 μg/mL) of B to 30 strains, which composed the normal main peak of sensitivity distribution,and the EC50 mean value (8.66±1.09 μg/mL) of Z to 37 strains,which composed the normal sensitivity distribution could be used as the baseline-sensitivity of Phytophthora nicotianae var.nicotianae to B and Z.更多还原