苹果轮纹病菌对甲基硫菌灵的敏感性基线

采用菌丝生长速率法测定了苹果轮纹病菌(Botryosphaeria dothidea)对甲基硫菌灵的敏感性。结果显示,EC50处于0.206 7~9.066 5 mg/L之间,平均为3.883 6±2.097 9 mg/L,与甲基硫菌灵对5个野生海棠菌株的EC50平均值3.041 3±0.296 5 mg/L无明显差异。正态检验表明,76个苹果轮纹病菌菌株对甲基硫菌灵的敏感性符合近似正态分布,山东省未出现产生抗药性的苹果轮纹病菌菌株,EC50平均值3.883 6±2.097 9 mg/L可作为苹果轮纹病菌对甲基硫菌灵的敏感性基线。

Sensitivity Baseline of Botryosphaeria dothidea from Apple to Thiophanate-methyl

Sensitivity in Botryosphaeria dothidea to thiophanate-methyl was determined by mycelium growth rate method in fungicide-amended media.50％ effective concentration (EC50) of thiophanate-methyl were between 0.206 7 mg/L and 9.066 5 mg/L and the mean EC50 was 3.883 6±2.097 9 mg/L.The mean EC50 for 5 white rot isolates of Chinese flowering crabapple without a previous history of fungicide exposure to thiophanate-methyl was 3.041 3±0.296 5 mg/L,which was not distinct from 3.883 6±2.097 9 mg/L.Normal distribution analysis showed that the sensitivity of isolates to thiophanate-methyl was fitted well with a normal distribution function.So far,resistance to thiophanate-methyl was not found in 76 isolates collected in Shandong province.The mean EC50 of 3.883 6±2.097 9 mg/L was made as sensitivity baseline of B.dothidea from apple to thiophanate-methyl.