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Erysiphe necator is an economically important biotrophic fungal pathogen responsible for powdery mildew disease on grapevine. Currently, genome sequences are available for only a few E. necator isolates from the United States. Based on the combination of Nanopore and Illumina sequencing technologies, we present here the complete genome assembly for an isolate of E. necator, NAFU1, identified in China. We acquired a total of 15.93 Gb of raw reads. These reads were processed into a 61.12-Mb genome assembly containing 73 contigs with an N 50 of 2.06 Mb and a maximum length of 6.05 Mb. Combining the results of three gene-prediction modules (i.e., an evidence-based gene modeler [EVidenceModeler], an ab initio gene modeler, and a homology-based gene modeler), we predicted 7,235 protein-coding genes in the assembled genome of E. necator NAFU1. This information will facilitate studies of genome evolution and pathogenicity mechanisms of E. necator and other powdery mildew species through comparative genome sequence analysis and other molecular genetic tools. [Formula: see text] Copyright © 2021 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license .
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This content will become publicly available on July 17, 2026
Nanopore sequencing and hybrid assembly: unraveling the genomic landscape of dollar spot with enhanced annotation and drug resistance profiling
The increasing multi-drug resistance observed in the turfgrass pathogenClarireediaspp. has emerged as a critical issue. Understanding the mechanisms underlying fungicide resistance is crucial to address this challenge. This study focuses on comparing a highly propiconazole-resistant isolate ofClarireedia jacksonii, HRI11, with a sensitive isolate, HRS10. Genomes were sequenced using the Oxford Nanopore MinION sequencing platform, and hybrid assembly was performed using this data and existing Pacific Biosciences long reads and Illumina short reads. HRI11 genome assembly represents the most contiguous and complete genome assembly reported forClarireediato date, spanning 43.6 MB with 12,831 predicted protein-coding genes across 51 scaffolds. In contrast, the HRS10 had an assembly size of 39.6 MB and encoded 12,161 putative proteins distributed over 100 scaffolds. While the two isolates share substantial sequence similarity and overall protein content, the fungicide resistance observed in HRI11 appears to arise primarily from genetic variants, particularly in genes encoding transcription factors, transporters, and fungicide target genes. These genetic variants establish a foundational resistance level against fungicides. Furthermore, induced resistance in HRI11 involves increased expression of proteins that facilitate fungicide efflux, thereby optimizing energy allocation during fungicide exposures. Together, these mechanisms-inherent genetic variation and adaptive transcriptional responses-contribute to the heightened resilience of HRI11 under fungicide treatment.
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- Award ID(s):
- 1942681
- PAR ID:
- 10617230
- Publisher / Repository:
- Frontiers Media SA
- Date Published:
- Journal Name:
- Frontiers in Fungal Biology
- Volume:
- 6
- ISSN:
- 2673-6128
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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