A highly multiplexed assay to monitor pathogenicity, fungicide resistance and gene flow in the fungal wheat pathogen Zymoseptoria tritici

• Published in: PloS one Vol. 18; no. 2; p. e0281181
• Main Authors: Bellah, Hadjer, Gazeau, Gwilherm, Gélisse, Sandrine, Amezrou, Reda, Marcel, Thierry C, Croll, Daniel
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 06.02.2023; Public Library of Science (PLoS)
• Subjects: Ascomycota - genetics; Assaying; Biology and Life Sciences; Crop diseases; Crop fields; Crop yield; Crops; Cultivars; Cytochrome; Deoxyribonucleic acid; Design; Design optimization; DNA; Environmental Sciences; Enzymes; Evaluation; Food production; Fungi; Fungicides; Fungicides, Industrial - pharmacology; Gene Flow; Gene frequency; Gene polymorphism; Genes; Genetic aspects; Genomes; Genomics; Genotypes; Health risks; Life Sciences; Management; Medicine and Health Sciences; Microfluidics; Monitoring; Multiplexing; Mutation; Pathogenicity; Pathogens; Pesticide resistance; Pesticides; Plant diseases; Plant Diseases - genetics; Plant Diseases - microbiology; Plant protection; Polymorphism; Population genetics; Population structure; Sustainable agriculture; Virulence; Virulence - genetics; Wheat; Zymoseptoria tritici; France; Resistance; Zymoseptoria tritici; pesticide; population
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0281181

Crop pathogens pose severe risks to global food production due to the rapid rise of resistance to pesticides and host resistance breakdowns. Predicting future risks requires monitoring tools to identify changes in the genetic composition of pathogen populations. Here we report the design of a microfluidics-based amplicon sequencing assay to multiplex 798 loci targeting virulence and fungicide resistance genes, and randomly selected genome-wide markers for the fungal pathogen Zymoseptoria tritici. The fungus causes one of the most devastating diseases on wheat showing rapid adaptation to fungicides and host resistance. We optimized the primer design by integrating polymorphism data from 632 genomes of the same species. To test the performance of the assay, we genotyped 192 samples in two replicates. Analysis of the short-read sequence data generated by the assay showed a fairly stable success rate across samples to amplify a large number of loci. The performance was consistent between samples originating from pure genomic DNA as well as material extracted directly from infected wheat leaves. In samples with mixed genotypes, we found that the assay recovers variations in allele frequencies. We also explored the potential of the amplicon assay to recover transposable element insertion polymorphism relevant for fungicide resistance. As a proof-of-concept, we show that the assay recovers the pathogen population structure across French wheat fields. Genomic monitoring of crop pathogens contributes to more sustainable crop protection and yields.