马铃薯晚疫病菌对瑞毒霉与霜脲氰的交互抗性

2008~2011年在黑龙江省共分离了41个马铃薯晚疫病菌,并测定了这些菌株对瑞毒霉和霜脲氰的敏感性和交互抗性。瑞毒霉测定结果显示6个(14.63%)菌株显示为敏感性,11个(26.83%)菌株显示为中抗,24个(58.54%)菌株显示为抗性。这说明黑龙江省分离的晚疫病菌已对瑞毒霉产生抗性。对于霜脲氰,EC50值为0.0630~2.1289μg/mL,最不敏感菌株是最敏感菌株的33.79倍,敏感性基线值为0.1879μg/mL。交互抗性分析结果显示,未产生交互抗性的菌株为73.16%,产生交互抗性菌株为26.84%。以上结果说明霜脲氰和瑞毒霉不能交叉使用。

Cross Resistance of Phytophthora infestans Isolates to Metalaxyl and Cymoxanil

A total of 41 Phytophthora infestans isolates were isolated from Heilongjiang Province,and determined for the sensitivity and cross resistance of these isolates to metalaxyl and cymoxanil.As for metalaxyl resistance,six(14.63%)isolates were sensitive,24(58.54%)isolates were intermediate resistant,and 24(58.54%) isolates were resistant.The results suggested that P.infestans isolates collected from Heilongjiang Province have occurred the resistance to metalaxyl.As for cymoxanil,EC50 values ranged from 0.0630 to 2.1289 μg / mL,with EC 50 values of the most insensitive isolate being 33.79 times the most sensitive,and the value of base line sensitivity was 0.1879 μg / mL.The results of cross resistance indicated that no cross resistant isolates was 73.16%,and cross resistant isolates was 26.84%.The above results suggested that cymoxanil could not be cross used with metalaxyl.