Plant Pathology, Institute of Integrative Biology, ETH Zürich, Zürich, Switzerland.
Laboratory of Evolutionary Genetics, Institute of Biology, University of Neuchâtel, Neuchâtel, Switzerland.
Genome Biol Evol. 2020 Dec 6;12(12):2231-2244. doi: 10.1093/gbe/evaa203.
Containing fungal diseases often depends on the application of fungicidal compounds. Fungicides can rapidly lose effectiveness due to the rise of resistant individuals in populations. However, the lack of knowledge about resistance mutations beyond known target genes challenges investigations into pathways to resistance. We used whole-genome sequencing data and association mapping to reveal the multilocus genetic architecture of fungicide resistance in a global panel of 159 isolates of Parastagonospora nodorum, an important fungal pathogen of wheat. We found significant differences in azole resistance among global field populations. The populations evolved distinctive combinations of resistance alleles which can interact when co-occurring in the same genetic background. We identified 34 significantly associated single nucleotide polymorphisms located in close proximity to genes associated with fungicide resistance in other fungi, including a major facilitator superfamily transporter. Using fungal colony growth rates and melanin production at different temperatures as fitness proxies, we found no evidence that resistance was constrained by genetic trade-offs. Our study demonstrates how genome-wide association studies of a global collection of pathogen strains can recapitulate the emergence of fungicide resistance. The distinct complement of resistance mutations found among populations illustrates how the evolutionary trajectory of fungicide adaptation can be complex and challenging to predict.
包含真菌病通常取决于杀真菌剂化合物的应用。由于种群中抗药性个体的增加，杀真菌剂可能会迅速失去效力。然而，除了已知的靶基因之外，对抗性突变的了解不足，这对研究抗性途径构成了挑战。我们使用全基因组测序数据和关联作图来揭示小麦重要真菌病原体 Parastagonospora nodorum 的 159 个分离株的全球群体中杀真菌剂抗性的多位点遗传结构。我们发现全球田间种群中唑类药物的抗性存在显著差异。这些种群进化出了独特的抗性等位基因组合，当它们在同一遗传背景中共存时，这些组合可以相互作用。我们鉴定了 34 个与其他真菌中与杀真菌剂抗性相关的基因密切相关的显著关联单核苷酸多态性，包括主要易化剂超家族转运蛋白。使用真菌菌落生长速率和不同温度下黑色素产量作为适合度替代物，我们没有发现抗性受到遗传权衡限制的证据。我们的研究表明，对全球病原体菌株进行全基因组关联研究如何重现杀真菌剂抗性的出现。在种群中发现的不同抗性突变体的补充说明了杀真菌剂适应性的进化轨迹可能是复杂的，难以预测。
