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Targeted genomic selection methodologies, or sequence capture, allow for DNA enrichment and large-scale resequencing and characterization of natural genetic variation in species with complex genomes, such as rapeseed canola (Brassica napus L., AACC, 2n=38). The main goal of this project was to combine sequence capture with next generation sequencing (NGS) to discover single nucleotide polymorphisms (SNPs) in specific areas of the B. napus genome historically associated (via quantitative trait loci -QTL- analysis) to traits of agronomical and nutritional importance. A 2.1 million feature sequence capture platform was designed to interrogate DNA sequence variation across 47 specific genomic regions, representing 51.2 Mb of the Brassica A and C genomes, in ten diverse rapeseed genotypes. All ten genotypes were sequenced using the 454 Life Sciences chemistry and to assess the effect of increased sequence depth, two genotypes were also sequenced using Illumina HiSeq chemistry. As a result, 589,367 potentially useful SNPs were identified. Analysis of sequence coverage indicated a four-fold increased representation of target regions, with 57% of the filtered SNPs falling within these regions. Sixty percent of discovered SNPs corresponded to transitions while 40% were transversions. Interestingly, fifty eight percent of the SNPs were found in genic regions while 42% were found in intergenic regions. Further, a high percentage of genic SNPs was found in exons (65% and 64% for the A and C genomes, respectively). Two different genotyping assays were used to validate the discovered SNPs. Validation rates ranged from 61.5% to 84% of tested SNPs, underpinning the effectiveness of this SNP discovery approach. Most importantly, the discovered SNPs were associated with agronomically important regions of the B. napus genome generating a novel data resource for research and breeding this crop species.

Large‐scale evaluation of genetic diversity in crops with large and complex genomes benefits from the selective enrichment of relevant genomic regions prior to sequencing. Given the complexity of the sugarcane (Saccharum spp.) genome and the limited exploration of quantitative trait loci (QTL) for important energy traits, we used comparative genomics with the related diploid crop sorghum (Sorghum bicolor) to mine for regions associated with bioenergy production. Twenty‐one meta‐QTL (mQTL) were identified after surveying 286 QTL from 24 different studies using the Sorghum QTL Atlas. Comparative genomics revealed that at least 35% of genes located within QTL can be found in highly conserved sorghum/sugarcane collinear chromosome blocks. Additionally, a targeted candidate search identified 200 genes known for their involvement in sugar and cell wall metabolism. For a subset of these sorghum genes, we evaluated sugarcane gene copy number, sequence identity, and homoeolog expression in target tissues. This work is an initial step towards targeting and resequencing sugarcane orthologous genomic regions to discover single nucleotide polymorphisms (SNPs) as a resource for genomics‐assisted breeding. [ABSTRACT FROM AUTHOR]