几种杀菌剂对致病疫霉抗甲霜灵菌株的活性测定

Bioactivitiy of Fungicides to Metalaxyl Resistant Isolate of Phytophthora infestans

测定了几种杀菌剂对致病疫霉抗甲霜灵菌株TZ25的室内毒力和盆栽防治效果。结果表明,嘧菌酯、氟啶胺、银法利(6.25%氟吡菌胺+62.5%霜霉威盐酸盐)和丙森锌对TZ25有很好的抑制作用,它们对TZ25菌丝生长的EC50值分别为0.0225、0.1560、0.9085、4.3665mg/L,对TZ25孢子囊萌发的EC50值分别为0.0301、0.1378、0.4143、2.0445mg/L。嘧菌酯、氟啶胺、银法利与甲霜灵没有交互抗性。盆栽试验结果表明,嘧菌酯、氟啶胺和银法利能很好地防治由TZ25引起的番茄晚疫病,防治效果分别为86.76%、82.15%、85.20%。

The bioactivity of several fungicides to metalaxyl resistant isolate TZ25 of Phytophthora infestans was studied. The results showed that azoxystrobin, fluazinam, infinito （6.25% fluopicolide ＋ 62.5% propamocath） and propineb gave strong fungistatic actions against TZ25. Their EC50 values to mycelial growth of TZ25 were 0.0225, 0.1560, 0.9085 and 4.3665 mg/L, respectively, and to sporangia germination were 0.0301, 0.1378, 0.4143 and 2.0445 mg/L, respectively. There was no cross resistance between metalaxyl and azoxystrobin, fluazinam, or infinito. The results of pot culture experiments indicated that azoxystrobin, fluazinam and infinito were effective for the control of tomato late blight caused by TZ25, and their control effects were 86.76, 82.15 and 85.20%, respectively.