马铃薯致病疫霉对嘧菌酯和氟吡菌胺的敏感性检测

Sensitivity Detection of Phytophthora infestans to Azoxystrobin and Fluopicolide

[目的]了解云南野马地区马铃薯致病疫霉对嘧菌酯和氟吡菌胺的抗性发生发展情况。[方法]采用菌丝生长速率法测定采自2012—2014年云南野马地区97株马铃薯致病疫霉对嘧菌酯和氟吡菌胺的敏感性,同时测定添加10mg/L水杨肟酸后病菌对嘧菌酯的敏感性。[结果]所有供试菌株在1 mg/L的嘧菌酯平板上均不生长,即对嘧菌酯均表现为敏感;2012、2013、2014年群体对氟吡菌胺的范围分别为0.279~0.884、0.252~0.582、0.171~0.710mg/L,其间无显著差异,EC_（50）总平均值为0.427mg/L。[结论]云南野马地区马铃薯致病疫霉尚未对嘧菌酯和氟吡菌胺产生抗性,97株菌株对氟吡菌胺的平均EC_（50）值可作为马铃薯致病疫霉对氟吡菌胺的敏感基线,为将来田间抗性监测提供参考。

[Aims]The aims were to investigate the development of fungicide resistance of Phytophthora infestans to azoxystrobin and fluopicolide in Yunnan province.[Methods]The sensitivities of 97 P.infestans isolated from Yema district in Yunnan province during 2012 and 2014 to azoxystrobin and fluopicolide were determined in vitro by using mycelium growth rate method;and the sensitivities to azoxystrobin plus 10 mg/L of salicylhydroxamic acid（SHAM）were also determined.[Results]The mycelium growth of all isolates were completely inhibited by 1 mg/L of azoxystrobin,which indicated that all isolates were sensitive to azoxystrobin;the EC_（50） values for population from 2012,2013 and 2014 were ranged from 0.279-0.884,0.252-0.582 and 0.171-0.710 mg/L,respectively,and there was no significant difference.In addition,the mean EC_（50） value was 0.427 mg/L for all 97 isolates.[Conclusions]The resistance of P.infestans to azoxystrobin and fluopicohde has not been occurred in Yema district,Yunnan province;the mean EC_（50） value for all 97 isolates can be a sensitivity baseline for P.infestans to fluopicolide,which can be a reference in resistance monitor in the future.