云南省昆明市马铃薯晚疫病菌甲霜灵抗药性监测

目的]明确云南省昆明市马铃薯晚疫病菌对甲霜灵的抗药性水平。方法]采用含药平板法测定晚疫病菌对不同浓度甲霜灵的相对生长量。结果]甲霜灵浓度为5、100μg/m L时,晚疫病菌相对生长量分别为59.24%~98.81%和43.25%~94.15%。52株马铃薯晚疫病菌全部为高抗菌,未检测到敏感和中抗菌株。结论]甲霜灵在昆明马铃薯产区已完全失效,需引进新型高效杀菌剂进行晚疫病的合理防控。

Metalaxyl Sensitivity of Phytophthora infestans on Potato in Kunming,Yunnan

Objective]To analyze the metalaxyl sensitivity of Phytophthora in festans collected from main potato production regions in Kunming, Yunnan.Method]Fungicide-amended petri plates were used to measure the relative growth of P.infestans based on three different fungicide con-centrations.Result]The relative growth of P.infestans was59.24%-98.81% on 5 μg/mL metalaxyl-amended plates and 43.25%-94.15%on 100 g/mL metalaxyl-amended plates,respectively.All fifty-two isolates of P.infestans were high resistance strains,and no sensitive and moder-ately resistant isolates were detected.Conclusion]The inhibition efficiency of metalaxyl to P.infestans has completely failed in Kunming.It is necessary to introduce and use new high efficient fungicides for rational management of late blight disease.