Genetic Variation and QTL Analysis of Crude Fibre and Quality Traits in the Doubled Haploid Winter Oilseed Rape (<i>Brassica napus</i> L.) Population R19 x Lord

ABSTRACT The oil‐extracted meal of oilseed rape is used for feeding livestock and is a potential source of vegetable protein for human consumption. Its protein quality is limited by glucosinolates, phenolic compounds, phytates and crude fibres. The reduction of cellulose, hemicellulose and indigestible lignin in black‐seeded oilseed rape may enhance the protein content, colour, sensory quality and digestibility. The objective of this study was to analyse the inheritance of seed fibre components in relation to oil, protein and other quality traits in a DH population derived from the cross of low lignin lines R19 and cv. Lord. The population of 143 lines was tested in field experiments in six environments and was genotyped with Illumina 15K Brassica SNP chip. QTL and candidate genes were identified using the high‐quality long‐read reference genome of Express 617. Major QTL for fibre components were identified on chromosomes C01 and C03 with opposite additive and epistatic effects. Fibre QTL colocated with each other and QTL for seed colour, oil and protein. Epistatic effects were identified, which resulted in a further decrease of fibre content.