Broad genotypic variation of a genetic diverse Brassica napus population

While the phenotype of 322 Brassica napus lines were screened for heat tolerance using a prototype heat screening facility, their genotypic variation was investigated.
Single nucleotide polymorphism (SNP) genotyping was performed using the Illumina Infinium 60K Brassica SNP array containing 52,157 SNP markers from the A and C sub-genomes in B. napus. Hybridization protocols were performed according to the manufacturer's instructions for all samples and the lined data was visualized and exported using Genome Studio v2.0.4 software (Illumina Inc., San Diego CA, USA). Then, SNPs with ≥ 20% missing data and monomorphic were omitted. The SNP data for the association analyses were exported in HapMap format, where the line can be either homozygous, heterozygous or missed call (NN). The SNPs were mapped to the Darmor-bzh v4 reference sequence (Chalhoub et al. 2014) via BLAST of the SNP probe sequences.