Whole Genome Re-Sequencing and Characterization of Powdery Mildew Disease-Associated Allelic Variation in Melon

• Published in: PloS one Vol. 11; no. 6; p. e0157524
• Main Authors: Natarajan, Sathishkumar, Kim, Hoy-Taek, Thamilarasan, Senthil Kumar, Veerappan, Karpagam, Park, Jong-In, Nou, Ill-Sup
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 16.06.2016; Public Library of Science (PLoS)
• Subjects: Airborne microorganisms; Alleles; Ascomycota - pathogenicity; Ascomycota - physiology; Biological activity; Biology and Life Sciences; Breeding; Chromosome Mapping; Chromosomes; Cucumis melo; Cucumis melo - genetics; Cucumis melo - immunology; Cucumis melo - microbiology; Cucurbitaceae; Cultivation; Deoxyribonucleic acid; Disease resistance; Disease Resistance - genetics; DNA; Food quality; Fruits; Fungal diseases; Gene sequencing; Genes; Genetic diversity; Genetics; Genome, Plant; Genomes; Genomics; High-Throughput Nucleotide Sequencing; Horticulture; INDEL Mutation; Multiculturalism & pluralism; Phenotype; Phenotypic variations; Plant diseases; Plant Diseases - genetics; Plant Diseases - immunology; Plant Diseases - microbiology; Plant Immunity - genetics; Polymorphism; Polymorphism, Single Nucleotide; Powdery mildew; Quantitative trait loci; Quantitative Trait Loci - immunology; Research and Analysis Methods; Single-nucleotide polymorphism; Sphaerotheca; Structure-function relationships; South Korea; China
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0157524

Powdery mildew is one of the most common fungal diseases in the world. This disease frequently affects melon (Cucumis melo L.) and other Cucurbitaceous family crops in both open field and greenhouse cultivation. One of the goals of genomics is to identify the polymorphic loci responsible for variation in phenotypic traits. In this study, powdery mildew disease assessment scores were calculated for four melon accessions, 'SCNU1154', 'Edisto47', 'MR-1', and 'PMR5'. To investigate the genetic variation of these accessions, whole genome re-sequencing using the Illumina HiSeq 2000 platform was performed. A total of 754,759,704 quality-filtered reads were generated, with an average of 82.64% coverage relative to the reference genome. Comparisons of the sequences for the melon accessions revealed around 7.4 million single nucleotide polymorphisms (SNPs), 1.9 million InDels, and 182,398 putative structural variations (SVs). Functional enrichment analysis of detected variations classified them into biological process, cellular component and molecular function categories. Further, a disease-associated QTL map was constructed for 390 SNPs and 45 InDels identified as related to defense-response genes. Among them 112 SNPs and 12 InDels were observed in powdery mildew responsive chromosomes. Accordingly, this whole genome re-sequencing study identified SNPs and InDels associated with defense genes that will serve as candidate polymorphisms in the search for sources of resistance against powdery mildew disease and could accelerate marker-assisted breeding in melon.