灰葡萄孢（Botrytis cinerea）对苯醚甲环唑的敏感性及其对不同杀菌剂的交互抗药性

采用菌丝生长速率法测定了山东省和河北省不同地区的157株灰葡萄孢对苯醚甲环唑的敏感性，结果表明，其中86株野生菌株对苯醚甲环唑的敏感性（EC50值）在0.0135～1.2832μg/mL之间，相差95.05倍，平均值为（0.3958±0.3485）μg/mL，可作为敏感基线。田间已出现对苯醚甲环唑的低抗菌株，占检测总株数的9.5%，未检测到中抗菌株和高抗菌株。通过测定灰葡萄孢不同菌株对苯醚甲环唑、嘧霉胺、腐霉利、多菌灵、乙霉威和异菌脲的敏感性，发现苯醚甲环唑与嘧霉胺、腐霉利、多菌灵、乙霉威和异菌脲之间不存在交互抗性关系。

The Sensitivity of Botrytis cinerea to Difenoconazole and Cross Resistance Against Diverse Fungicides

The Sensitivity of Botrytis cinerea to difenoconazole was tested in Shandong and Hebei provinces of main tomato production and cross-resistances of difenoconazole with botryticides were also examined;The sensitivity of Botrytis cinerea to difenoconazole was tested by measuring mycelial growth rate and cross-risistances of difenoconazole with botryticides were examined through analysing the correlation coefficent of the logarithms of that EC 50 of difenoconazole and botryticides to B.cinerea.EC 50 values for 86 isolates from the areas where the difenoconazole have never been used before were （0.3958 ± 0.3485） μg/mL,ranging from 0.0135μg/mL to 1.2832 μg/mL.The data could be used as baseline-sensitivity of B.cinerea to difenoconazole.The results of monitoring showed that low resistant isolates to difenoconazole in B.cinerea occurred in collected areas,9.5% low resistant isolates existed,but moderate resistant or high resistant isolates were not detected.The correlation coefficent of the logarithms of that EC 50 values between difenoconazole and other fungicides that pyrimethanil,iprodione,procymidone,carbendazim,and diethofencarb to B.cinerea were 0.0192、0.0253、0.0053、0.0146 and 0.0567.The results indicated that there were no positively-correlated cross-resistance between difenoconazole and other diverse active mechanism fungicides.Difenoconazole was expected to be a substituted pesticide in controlling gray mold,duing to difenoconazole had highly activity against Botrytis cinerea and there were no positively-correlated cross resistance between difenoconazole and other diverse active mechanism fungicides