甘肃玉米大斑病菌对吡唑醚菌酯的敏感性监测分析

Monitoring and Analyzing Sensitivity of Setosphaeria turcica to Pyraclostrobin in Gansu

为明确甘肃玉米大斑病菌对吡唑醚菌酯的敏感基线和抗药性水平,采用平皿法测定甘肃省4个典型生态区57株玉米大斑病菌对吡唑醚菌酯的敏感性。结果表明,甘肃玉米大斑病菌对吡唑醚菌酯的敏感性差异较小,EC50为0.10-1.56mg/L,EC50平均值为0.66mg/L,49株菌株EC50连续性正态分布时的EC50平均值0.61mg/L即为甘肃玉米大斑病菌对吡唑醚菌酯的敏感基线;基于此发现,甘肃玉米大斑病菌对吡唑醚菌酯的平均抗性为1.08,最高抗性为2.55,暂未出现抗药性,其中中部干旱雨养生态区5株菌株十分敏感,平均抗性和最高抗性分别为0.84和1.11,而河西干旱灌溉生态区15株菌株敏感性较低,平均抗性和最高抗性分别为1.23和2.55,需警惕其抗药性。

The sensitivity of 57 isolates of Setosphaeria turcica to pyraclostrobin on four typical ecological regions in Gansu was tested by Petri plate in order to determine their sensitive baseline and resistance factor. The results showed that the sensitivity of S. turcica to pyraclostrobin in Gansu is little different,ECs0 range is 0.10-1.56 mg/L,mean EC50 is 0.66 mg/L. The sensitive baseline of S. turcica to azoxystrobin in Gansu is 0.61 mg/L only when normality test of EC50 on 49 isolates of S. turcica is continuously normal distribution. On the base of sensitive baseline, we find that the highest and mean resistance factor for 57 isolates to pyraclostrobin is respectively 2.55 and 1.08 in Gansu,and there is no resistance. 5 isolates from rainfed dryland in Central is sensitive to pyraclostrobin, the highest and mean resistance factor for resistance to pyraclostrohin is respectively 1.11 and 0.84,as well as 15 isolates from irrigated dryland in Hexi is lowly sensitive to pyraclostrobin, the highest and mean resistance factor for resistance to pyraclostrobin is respectively 2.55 and 1.23 ,we need to be wary of the resistance.