Phenylamide-resistant isolates of Phytophthora infestans have gradually become an important part of populations in many countries. However, fungicide mixtures containing a phenylamide component are still an effective strategy for the control of late blight in potato and tomato. The proportion of phenylamide-resistant isolates fluctuates from year to year and within the season. Almost concurrent with the appearance of resistant isolates was the discovery of the A2 mating type of P. infestans in many European countries and in other parts of the world. However, no genetic correlation exists between resistance and mating type, and the proportion of A2 isolates in European populations remains small. Resistance to phenylamides became established in A1 populations before the appearance of A2 type. Resistant isolates express equal or greater fitness than sensitive isolates, but no correlation was detected between resistance and race structure. The continuous changes in P. infestans populations require careful adaptation of successful disease control programs.

中文翻译：

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对苯甲酰胺类杀真菌剂的抗性：疫霉菌感染的一个案例研究，涉及交配类型和种族结构。

疫霉疫霉的耐苯甲酰胺分离株已逐渐成为许多国家人口的重要组成部分。但是，含有苯酰胺成分的杀菌剂混合物仍然是控制马铃薯和番茄晚疫病的有效策略。耐苯酰胺菌株的比例每年都在该季节内波动。与耐药菌株的出现几乎同时出现的是，在许多欧洲国家和世界其他地区发现了A2交配型致病疫霉。但是，抗性和交配类型之间不存在遗传相关性，并且欧洲人群中A2分离株的比例仍然很小。在出现A2型之前，对A1人群已经建立了对苯酰胺的抗药性。抗性分离株的适应性比敏感分离株更高，但在抗性和种族结构之间未发现相关性。P. infestans种群的持续变化需要对成功的疾病控制程序进行仔细的调整。